Sample records for joint demographic history

  1. Medical and Demographic History: Inseparable?

    Microsoft Academic Search

    Robert Woods

    2007-01-01

    Summary. The case is made for forms of medical history that focus explicitly on sickness, health and life chances; ones that explore the effects of health interventions by examining their impact on mor- tality risks. Using a series of examples drawn from environmental health, midwifery and obstetric care, the paper illustrates various ways in which long-term trends in health and

  2. ORIGINAL ARTICLE Speciation and demographic history of Atlantic eels

    E-print Network

    Bernatchez, Louis

    ORIGINAL ARTICLE Speciation and demographic history of Atlantic eels (Anguilla anguilla and A environments without obvious physical barriers remain poorly known. European and American eel (Anguilla, in which case American eel would be expected to be the ancestral species. This scenario could, however

  3. UNDERSTANDING HOW HARVEST INFLUENCES THE LIFE HISTORY AND DEMOGRAPHICS OF SHOVELNOSE STURGEON IN THE MIDDLE

    E-print Network

    UNDERSTANDING HOW HARVEST INFLUENCES THE LIFE HISTORY AND DEMOGRAPHICS OF SHOVELNOSE STURGEON HARVEST INFLUENCES THE LIFE HISTORY AND DEMOGRAPHICS OF SHOVELNOSE STURGEON IN THE MIDDLE MISSISSIPPI the Life History and Demographics of Shovelnose Sturgeon in the Middle Mississippi River MAJOR PROFESSORS

  4. Cattle demographic history modelled from autosomal sequence variation

    PubMed Central

    Murray, Caitriona; Huerta-Sanchez, Emilia; Casey, Fergal; Bradley, Daniel G.

    2010-01-01

    The phylogeography of cattle genetic variants has been extensively described and has informed the history of domestication. However, there remains a dearth of demographic models inferred from such data. Here, we describe sequence diversity at 37 000 bp sampled from 17 genes in cattle from Africa, Europe and India. Clearly distinct population histories are suggested between Bos indicus and Bos taurus, with the former displaying higher diversity statistics. We compare the unfolded site frequency spectra in each to those simulated using a diffusion approximation method and build a best-fitting model of past demography. This implies an earlier, possibly glaciation-induced population bottleneck in B. taurus ancestry with a later, possibly domestication-associated demographic constriction in B. indicus. Strikingly, the modelled indicine history also requires a majority secondary admixture from the South Asian aurochs, indicating a complex, more diffuse domestication process. This perhaps involved multiple domestications and/or introgression from wild oxen to domestic herds; the latter is plausible from archaeological evidence of contemporaneous wild and domestic remains across different regions of South Asia. PMID:20643743

  5. Linkage Disequilibrium and Demographic History of Wild and Domestic Canids

    PubMed Central

    Gray, Melissa M.; Granka, Julie M.; Bustamante, Carlos D.; Sutter, Nathan B.; Boyko, Adam R.; Zhu, Lan; Ostrander, Elaine A.; Wayne, Robert K.

    2009-01-01

    Assessing the extent of linkage disequilibrium (LD) in natural populations of a nonmodel species has been difficult due to the lack of available genomic markers. However, with advances in genotyping and genome sequencing, genomic characterization of natural populations has become feasible. Using sequence data and SNP genotypes, we measured LD and modeled the demographic history of wild canid populations and domestic dog breeds. In 11 gray wolf populations and one coyote population, we find that the extent of LD as measured by the distance at which r2 = 0.2 extends <10 kb in outbred populations to >1.7 Mb in populations that have experienced significant founder events and bottlenecks. This large range in the extent of LD parallels that observed in 18 dog breeds where the r2 value varies from ?20 kb to >5 Mb. Furthermore, in modeling demographic history under a composite-likelihood framework, we find that two of five wild canid populations exhibit evidence of a historical population contraction. Five domestic dog breeds display evidence for a minor population contraction during domestication and a more severe contraction during breed formation. Only a 5% reduction in nucleotide diversity was observed as a result of domestication, whereas the loss of nucleotide diversity with breed formation averaged 35%. PMID:19189949

  6. Demographic history and rare allele sharing among human populations.

    PubMed

    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

    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

  7. Impact of Sampling Schemes on Demographic Inference: An Empirical Study in Two Species with Different Mating Systems and Demographic Histories

    PubMed Central

    St. Onge, K. R.; Palmé, A. E.; Wright, S. I.; Lascoux, M.

    2012-01-01

    Most species have at least some level of genetic structure. Recent simulation studies have shown that it is important to consider population structure when sampling individuals to infer past population history. The relevance of the results of these computer simulations for empirical studies, however, remains unclear. In the present study, we use DNA sequence datasets collected from two closely related species with very different histories, the selfing species Capsella rubella and its outcrossing relative C. grandiflora, to assess the impact of different sampling strategies on summary statistics and the inference of historical demography. Sampling strategy did not strongly influence the mean values of Tajima’s D in either species, but it had some impact on the variance. The general conclusions about demographic history were comparable across sampling schemes even when resampled data were analyzed with approximate Bayesian computation (ABC). We used simulations to explore the effects of sampling scheme under different demographic models. We conclude that when sequences from modest numbers of loci (<60) are analyzed, the sampling strategy is generally of limited importance. The same is true under intermediate or high levels of gene flow (4Nm > 2–10) in models in which global expansion is combined with either local expansion or hierarchical population structure. Although we observe a less severe effect of sampling than predicted under some earlier simulation models, our results should not be seen as an encouragement to neglect this issue. In general, a good coverage of the natural range, both within and between populations, will be needed to obtain a reliable reconstruction of a species’s demographic history, and in fact, the effect of sampling scheme on polymorphism patterns may itself provide important information about demographic history. PMID:22870403

  8. [Hereditary spherocytosis: Review. Part I. History, demographics, pathogenesis, and diagnosis].

    PubMed

    Donato, Hugo; Crisp, Renée Leonor; Rapetti, María Cristina; García, Eliana; Attie, Myriam

    2015-01-01

    Hereditary spherocytosis is the most frequent hereditary anemia excluding beta thalassemia in Argentina. Historical, demographic, genetic and pathogenic aspects of the disease are reviewed, and confirmatory laboratory tests are described. Special characteristics on the outcome of the disease in our population and prevalent protein deficiencies in our country are described. Emphasis is given on new available laboratory tests, which allow an earlier diagnosis using volume of blood samples significantly smaller than required for conventional tests. PMID:25622164

  9. Demographic analysis of continuous-time life-history models

    Microsoft Academic Search

    Roos de A. M

    2007-01-01

    I present a computational approach to calculate the population growth rate, its sensitivity to life-history parameters and associated statistics like the stable population distribution and the reproductive value for exponentially growing populations, in which individual life history is described as a continuous development through time. The method is generally applicable to analyse population growth and performance for a wide range

  10. Demographic analysis of continuous-time life-history models

    PubMed Central

    De Roos, André M

    2008-01-01

    I present a computational approach to calculate the population growth rate, its sensitivity to life-history parameters and associated statistics like the stable population distribution and the reproductive value for exponentially growing populations, in which individual life history is described as a continuous development through time. The method is generally applicable to analyse population growth and performance for a wide range of individual life-history models, including cases in which the population consists of different types of individuals or in which the environment is fluctuating periodically. It complements comparable methods developed for discrete-time dynamics modelled with matrix or integral projection models. The basic idea behind the method is to use Lotka's integral equation for the population growth rate and compute the integral occurring in that equation by integrating an ordinary differential equation, analogous to recently derived methods to compute steady-states of physiologically structured population models. I illustrate application of the method using a number of published life-history models. PMID:18047588

  11. Multilocus patterns of nucleotide variability and the demographic and selection history

    E-print Network

    of Drosophila melanogaster populations Penelope R. Haddrill,1 Kevin R. Thornton,2 Brian Charlesworth,1 and Peter the demographic history of populations can hamper genome-wide scans for selection based on population genetic in Drosophila melanogaster populations, we surveyed noncoding DNA polymorphism at 10 X-linked loci in large

  12. Patterns of Polymorphism and Demographic History in Natural Populations of Arabidopsis lyrata

    Microsoft Academic Search

    Jeffrey Ross-Ibarra; Stephen I. Wright; John Paul Foxe; Akira Kawabe; Leah Derose-Wilson; Gesseca Gos; Deborah Charlesworth; Brandon S. Gaut; Justin C. Fay

    2008-01-01

    BackgroundMany of the processes affecting genetic diversity act on local populations. However, studies of plant nucleotide diversity have largely ignored local sampling, making it difficult to infer the demographic history of populations and to assess the importance of local adaptation. Arabidopsis lyrata, a self-incompatible, perennial species with a circumpolar distribution, is an excellent model system in which to study the

  13. Effects of Pleistocene climatic fluctuations on the phylogeographic and demographic histories of Pacific

    E-print Network

    Avise, John

    Effects of Pleistocene climatic fluctuations on the phylogeographic and demographic histories evidence, we infer that the genetic make-up of extant populations of C. pallasii was shaped by Pleistocene, phylogeography, Pleistocene glaciation, popula- tion demography Received 14 March 2011; revision received 14 June

  14. Effects of landscape and demographic history on genetic variation in Picea glehnii at the regional scale

    Microsoft Academic Search

    Susumu Goto; Yoshiaki Tsuda; Yukihiro Koike; Chunlan Lian; Yuji Ide

    2009-01-01

    To evaluate the effects of landscape and demographic history on genetic variation in Picea glehnii at a regional scale we have investigated the genetic diversity and genetic differentiation of P. glehnii populations in the Furano region, central Hokkaido, Japan, using seven simple sequence repeat (SSR) markers. We found significant\\u000a correlations between elevation and genetic diversity parameters. The value of A

  15. Joint Genome Institute's Automation Approach and History

    SciTech Connect

    Roberts, Simon

    2006-07-05

    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.

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

    PubMed Central

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

    2013-01-01

    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. PMID:24312576

  17. How the World Survived the Population Bomb: Lessons From 50 Years of Extraordinary Demographic History

    PubMed Central

    Lam, David

    2012-01-01

    The world population will reach 7 billion in late 2011, a demographic milestone that is causing renewed attention to the challenges caused by population growth. This article looks at the last 50 years of demographic change, one of the most extraordinary periods in demographic history. During this period, world population grew at rates that have never been seen before and will almost surely never be seen again. There were many concerns about the potential impact of rapid population growth in the 1960s, including mass starvation in countries such as India, depletion of nonrenewable resources, and increased poverty in low-income countries. The actual experience was very different. World food production increased faster than world population in every decade since the 1960s, resource prices fell during most of the period, and poverty declined significantly in much of the developing world. The article considers the economic and demographic explanations for the surprising successes of this important period in demographic history. It also looks at regions that have been less successful, especially Africa, and at the lessons for dealing with the important challenges that still remain. PMID:22005884

  18. Life history and demographic variation in the lizard Sceloporus graciosus: A long-term study

    Microsoft Academic Search

    D. W. Tinkle; A. E. Dunham; J. D. Congdon

    1993-01-01

    An 11-yr study of life history and demographic variation in the sagebrush lizard Sceloporus graciosus was carried out on two study areas (Rattlesnake Ridge and Ponderosa Flat) in the Kolob Mesa Section of Zion National Park, Utah. Two primary objectives of this mark-recapture study were to: (1) quantify variation in age structure, age, and size at maturity, age-specific survivorship and

  19. Reconstructing the demographic history of orang-utans using Approximate Bayesian Computation.

    PubMed

    Nater, Alexander; Greminger, Maja P; Arora, Natasha; van Schaik, Carel P; Goossens, Benoit; Singleton, Ian; Verschoor, Ernst J; Warren, Kristin S; Krützen, Michael

    2015-01-01

    Investigating how different evolutionary forces have shaped patterns of DNA variation within and among species requires detailed knowledge of their demographic history. Orang-utans, whose distribution is currently restricted to the South-East Asian islands of Borneo (Pongo pygmaeus) and Sumatra (Pongo abelii), have likely experienced a complex demographic history, influenced by recurrent changes in climate and sea levels, volcanic activities and anthropogenic pressures. Using the most extensive sample set of wild orang-utans to date, we employed an Approximate Bayesian Computation (ABC) approach to test the fit of 12 different demographic scenarios to the observed patterns of variation in autosomal, X-chromosomal, mitochondrial and Y-chromosomal markers. In the best-fitting model, Sumatran orang-utans exhibit a deep split of populations north and south of Lake Toba, probably caused by multiple eruptions of the Toba volcano. In addition, we found signals for a strong decline in all Sumatran populations ~24 ka, probably associated with hunting by human colonizers. In contrast, Bornean orang-utans experienced a severe bottleneck ~135 ka, followed by a population expansion and substructuring starting ~82 ka, which we link to an expansion from a glacial refugium. We showed that orang-utans went through drastic changes in population size and connectedness, caused by recurrent contraction and expansion of rainforest habitat during Pleistocene glaciations and probably hunting by early humans. Our findings emphasize the fact that important aspects of the evolutionary past of species with complex demographic histories might remain obscured when applying overly simplified models. PMID:25439562

  20. Inferring population structure and demographic history using Y-STR data from worldwide populations.

    PubMed

    Xu, Hongyang; Wang, Chuan-Chao; Shrestha, Rukesh; Wang, Ling-Xiang; Zhang, Manfei; He, Yungang; Kidd, Judith R; Kidd, Kenneth K; Jin, Li; Li, Hui

    2015-02-01

    The Y chromosome is one of the best genetic materials to explore the evolutionary history of human populations. Global analyses of Y chromosomal short tandem repeats (STRs) data can reveal very interesting world population structures and histories. However, previous Y-STR works tended to focus on small geographical ranges or only included limited sample sizes. In this study, we have investigated population structure and demographic history using 17 Y chromosomal STRs data of 979 males from 44 worldwide populations. The largest genetic distances have been observed between pairs of African and non-African populations. American populations with the lowest genetic diversities also showed large genetic distances and coancestry coefficients with other populations, whereas Eurasian populations displayed close genetic affinities. African populations tend to have the oldest time to the most recent common ancestors (TMRCAs), the largest effective population sizes and the earliest expansion times, whereas the American, Siberian, Melanesian, and isolated Atayal populations have the most recent TMRCAs and expansion times, and the smallest effective population sizes. This clear geographic pattern is well consistent with serial founder model for the origin of populations outside Africa. The Y-STR dataset presented here provides the most detailed view of worldwide population structure and human male demographic history, and additionally will be of great benefit to future forensic applications and population genetic studies. PMID:25159112

  1. Statistical inference on genetic data reveals the complex demographic history of human populations in central Asia.

    PubMed

    Palstra, Friso P; Heyer, Evelyne; Austerlitz, Frédéric

    2015-06-01

    The demographic history of modern humans constitutes a combination of expansions, colonizations, contractions, and remigrations. The advent of large scale genetic data combined with statistically refined methods facilitates inference of this complex history. Here we study the demographic history of two genetically admixed ethnic groups in Central Asia, an area characterized by high levels of genetic diversity and a history of recurrent immigration. Using Approximate Bayesian Computation, we infer that the timing of admixture markedly differs between the two groups. Admixture in the traditionally agricultural Tajiks could be dated back to the onset of the Neolithic transition in the region, whereas admixture in Kyrgyz is more recent, and may have involved the westward movement of Turkic peoples. These results are confirmed by a coalescent method that fits an isolation-with-migration model to the genetic data, with both Central Asian groups having received gene flow from the extremities of Eurasia. Interestingly, our analyses also uncover signatures of gene flow from Eastern to Western Eurasia during Paleolithic times. In conclusion, the high genetic diversity currently observed in these two Central Asian peoples most likely reflects the effects of recurrent immigration that likely started before historical times. Conversely, conquests during historical times may have had a relatively limited genetic impact. These results emphasize the need for a better understanding of the genetic consequences of transmission of culture and technological innovations, as well as those of invasions and conquests. PMID:25678589

  2. Life-history and demographic spatial variation in Mediterranean populations of the opportunistic polychaete Ophryotrocha labronica (Polychaeta, Dorvilleidae)

    Microsoft Academic Search

    Gloria Massamba-N’Siala; Roberto Simonini; Piero Cossu; Ferruccio Maltagliati; Alberto Castelli; Daniela Prevedelli

    2011-01-01

    The spatial scale of life-history and demographic variation was investigated in the opportunistic polychaete Ophryotrocha labronica La Greca and Bacci. Individuals were collected along the Italian coasts from three thermally different biogeographical regions\\u000a of the Mediterranean Sea. For each region, populations from four harbours were considered, and for each harbour, two sites\\u000a were examined. Life-history and demographic traits were investigated

  3. Estimating genome-wide heterozygosity: effects of demographic history and marker type

    PubMed Central

    Miller, J M; Malenfant, R M; David, P; Davis, C S; Poissant, J; Hogg, J T; Festa-Bianchet, M; Coltman, D W

    2014-01-01

    Heterozygosity–fitness correlations (HFCs) are often used to link individual genetic variation to differences in fitness. However, most studies examining HFCs find weak or no correlations. Here, we derive broad theoretical predictions about how many loci are needed to adequately measure genomic heterozygosity assuming different levels of identity disequilibrium (ID), a proxy for inbreeding. We then evaluate the expected ability to detect HFCs using an empirical data set of 200 microsatellites and 412 single nucleotide polymorphisms (SNPs) genotyped in two populations of bighorn sheep (Ovis canadensis), with different demographic histories. In both populations, heterozygosity was significantly correlated across marker types, although the strength of the correlation was weaker in a native population compared with one founded via translocation and later supplemented with additional individuals. Despite being bi-allelic, SNPs had similar correlations to genome-wide heterozygosity as microsatellites in both populations. For both marker types, this association became stronger and less variable as more markers were considered. Both populations had significant levels of ID; however, estimates were an order of magnitude lower in the native population. As with heterozygosity, SNPs performed similarly to microsatellites, and precision and accuracy of the estimates of ID increased as more loci were considered. Although dependent on the demographic history of the population considered, these results illustrate that genome-wide heterozygosity, and therefore HFCs, are best measured by a large number of markers, a feat now more realistically accomplished with SNPs than microsatellites. PMID:24149650

  4. Demographic history of an elusive carnivore: using museums to inform management

    PubMed Central

    Holbrook, Joseph D; DeYoung, Randy W; Tewes, Michael E; Young, John H

    2012-01-01

    Elusive carnivores present a challenge to managers because traditional survey methods are not suitable. We applied a genetic approach using museum specimens to examine how historical and recent conditions influenced the demographic history of Puma concolor in western and southern Texas, USA. We used 10 microsatellite loci and indexed population trends by estimating historical and recent genetic diversity, genetic differentiation and effective population size. Mountain lions in southern Texas exhibited a 9% decline in genetic diversity, whereas diversity remained stable in western Texas. Genetic differentiation between western and southern Texas was minimal historically (FST = 0.04, P < 0.01), but increased 2–2.5 times in our recent sample. An index of genetic drift for southern Texas was seven to eight times that of western Texas, presumably contributing to the current differentiation between western and southern Texas. Furthermore, southern Texas exhibited a >50% temporal decline in effective population size, whereas western Texas showed no change. Our results illustrate that population declines and genetic drift have occurred in southern Texas, likely because of contemporary habitat loss and predator control. Population monitoring may be needed to ensure the persistence of mountain lions in the southern Texas region. This study highlights the utility of sampling museum collections to examine demographic histories and inform wildlife management. PMID:23028402

  5. Demographic History, Population Structure, and Local Adaptation in Alpine Populations of Cardamine impatiens and Cardamine resedifolia

    PubMed Central

    Ometto, Lino; Li, Mingai; Bresadola, Luisa; Barbaro, Enrico; Neteler, Markus; Varotto, Claudio

    2015-01-01

    Species evolution depends on numerous and distinct forces, including demography and natural selection. For example, local adaptation and population structure affect the evolutionary history of species living along environmental clines. This is particularly relevant in plants, which are often characterized by limited dispersal ability and the need to respond to abiotic and biotic stress factors specific to the local environment. Here we study the demographic history and the possible existence of local adaptation in two related species of Brassicaceae, Cardamine impatiens and Cardamine resedifolia, which occupy separate habitats along the elevation gradient. Previous genome-wide analyses revealed the occurrence of distinct selective pressures in the two species, with genes involved in cold response evolving particularly fast in C. resedifolia. In this study we surveyed patterns of molecular evolution and genetic variability in a set of 19 genes, including neutral and candidate genes involved in cold response, across 10 populations each of C. resedifolia and C. impatiens from the Italian Alps (Trentino). We inferred the population structure and demographic history of the two species, and tested the occurrence of signatures of local adaptation in these genes. The results indicate that, despite a slightly higher population differentiation in C. resedifolia than in C. impatiens, both species are only weakly structured and that populations sampled at high altitude experience less gene flow than low-altitude ones. None of the genes showed signatures of positive selection, suggesting that they do not seem to play relevant roles in the current evolutionary processes of adaptation to alpine environments of these species. PMID:25933225

  6. Interaction between socio-demographic characteristics: traffic rule violations and traffic crash history for young drivers.

    PubMed

    Alver, Y; Demirel, M C; Mutlu, M M

    2014-11-01

    Young drivers' high traffic violation involvement rate and significant contribution to traffic crashes compared to older drivers creates the need for detailed analyses of factors affecting young drivers' behaviors. This study is based on survey data collected from 2,057 18-29 year old young adults. Data were collected via face-to-face questionnaire surveys in four different cities in Turkey. The main objective of this study is to identify the relationship between socio-demographic characteristics, traffic rule violations, and traffic crashes among young drivers. Four main traffic rule violations are examined: red light violations, seat belt violations, speeding, and driving under the influence of alcohol, which are decisive in determining driving behavior and traffic crashes. The survey investigates the socio-demographic characteristics, traffic rule violation behavior and traffic crash histories of young adults. Four hypothetical scenarios were prepared for each traffic rule violation and data from the scenarios were modeled using the ordered probit model. Significant variables affecting each traffic rule violation are stated. Finally, significant variables that interact with crash involvements were investigated with binary logit models. According to the data analysis, 23.9% of drivers stated that they were involved in at least one traffic crash within the last three years. This crash rate increases to 38.3% for those who received at least one traffic citation/violation in last three years and peaks to 47.4% for those who were fined for seat belt violations in last three years. PMID:25019690

  7. Life history and demographic variation in the lizard Sceloporus graciosus: A long-term study

    SciTech Connect

    Tinkle, D.W. (Univ. of Michigan, Ann Arbor, MI (United States)); Dunham, A.E. (Univ. of Pennsylvania, Philadelphia, PA (United States)); Congdon, J.D. (Savannah River Ecology Lab., Aiken, SC (United States))

    1993-12-01

    An 11-yr study of life history and demographic variation in the sagebrush lizard Sceloporus graciosus was carried out on two study areas (Rattlesnake Ridge and Ponderosa Flat) in the Kolob Mesa Section of Zion National Park, Utah. Two primary objectives of this mark-recapture study were to: (1) quantify variation in age structure, age, and size at maturity, age-specific survivorship and fecundity, and individual growth rates, and (2) conduct a series of density reduction experiments designed to elucidate the effects of density on growth rates and survival of posthatchling lizards. In addition, the authors examined the relationships of variation in population density and deviation from long-term average precipitation and temperature to variation in individual growth, reproduction, and demography. 43 refs., 5 figs., 11 tabs.

  8. Whole-genome sequencing of giant pandas provides insights into demographic history and local adaptation.

    PubMed

    Zhao, Shancen; Zheng, Pingping; Dong, Shanshan; Zhan, Xiangjiang; Wu, Qi; Guo, Xiaosen; Hu, Yibo; He, Weiming; Zhang, Shanning; Fan, Wei; Zhu, Lifeng; Li, Dong; Zhang, Xuemei; Chen, Quan; Zhang, Hemin; Zhang, Zhihe; Jin, Xuelin; Zhang, Jinguo; Yang, Huanming; Wang, Jian; Wang, Jun; Wei, Fuwen

    2013-01-01

    The panda lineage dates back to the late Miocene and ultimately leads to only one extant species, the giant panda (Ailuropoda melanoleuca). Although global climate change and anthropogenic disturbances are recognized to shape animal population demography their contribution to panda population dynamics remains largely unknown. We sequenced the whole genomes of 34 pandas at an average 4.7-fold coverage and used this data set together with the previously deep-sequenced panda genome to reconstruct a continuous demographic history of pandas from their origin to the present. We identify two population expansions, two bottlenecks and two divergences. Evidence indicated that, whereas global changes in climate were the primary drivers of population fluctuation for millions of years, human activities likely underlie recent population divergence and serious decline. We identified three distinct panda populations that show genetic adaptation to their environments. However, in all three populations, anthropogenic activities have negatively affected pandas for 3,000 years. PMID:23242367

  9. Population genetic structure and demographic history of Atrina pectinata based on mitochondrial DNA and microsatellite markers.

    PubMed

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

    2014-01-01

    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. PMID:24789175

  10. Demographic histories and genetic diversities of Fennoscandian marine and landlocked ringed seal subspecies

    PubMed Central

    Nyman, Tommi; Valtonen, Mia; Aspi, Jouni; Ruokonen, Minna; Kunnasranta, Mervi; Palo, Jukka U

    2014-01-01

    Island populations are on average smaller, genetically less diverse, and at a higher risk to go extinct than mainland populations. Low genetic diversity may elevate extinction probability, but the genetic component of the risk can be affected by the mode of diversity loss, which, in turn, is connected to the demographic history of the population. Here, we examined the history of genetic erosion in three Fennoscandian ringed seal subspecies, of which one inhabits the Baltic Sea ‘mainland’ and two the ‘aquatic islands’ composed of Lake Saimaa in Finland and Lake Ladoga in Russia. Both lakes were colonized by marine seals after their formation c. 9500 years ago, but Lake Ladoga is larger and more contiguous than Lake Saimaa. All three populations suffered dramatic declines during the 20th century, but the bottleneck was particularly severe in Lake Saimaa. Data from 17 microsatellite loci and mitochondrial control-region sequences show that Saimaa ringed seals have lost most of the genetic diversity present in their Baltic ancestors, while the Ladoga population has experienced only minor reductions. Using Approximate Bayesian computing analyses, we show that the genetic uniformity of the Saimaa subspecies derives from an extended founder event and subsequent slow erosion, rather than from the recent bottleneck. This suggests that the population has persisted for nearly 10,000 years despite having low genetic variation. The relatively high diversity of the Ladoga population appears to result from a high number of initial colonizers and a high post-colonization population size, but possibly also by a shorter isolation period and/or occasional gene flow from the Baltic Sea. PMID:25535558

  11. Y-Chromosome Evidence for Differing Ancient Demographic Histories in the Americas

    PubMed Central

    Bortolini, Maria-Catira; Salzano, Francisco M.; Thomas, Mark G.; Stuart, Steven; Nasanen, Selja P. K.; Bau, Claiton H. D.; Hutz, Mara H.; Layrisse, Zulay; Petzl-Erler, Maria L.; Tsuneto, Luiza T.; Hill, Kim; Hurtado, Ana M.; Castro-de-Guerra, Dinorah; Torres, Maria M.; Groot, Helena; Michalski, Roman; Nymadawa, Pagbajabyn; Bedoya, Gabriel; Bradman, Neil; Labuda, Damian; Ruiz-Linares, Andres

    2003-01-01

    To scrutinize the male ancestry of extant Native American populations, we examined eight biallelic and six microsatellite polymorphisms from the nonrecombining portion of the Y chromosome, in 438 individuals from 24 Native American populations (1 Na Dené and 23 South Amerinds) and in 404 Mongolians. One of the biallelic markers typed is a recently identified mutation (M242) characterizing a novel founder Native American haplogroup. The distribution, relatedness, and diversity of Y lineages in Native Americans indicate a differentiated male ancestry for populations from North and South America, strongly supporting a diverse demographic history for populations from these areas. These data are consistent with the occurrence of two major male migrations from southern/central Siberia to the Americas (with the second migration being restricted to North America) and a shared ancestry in central Asia for some of the initial migrants to Europe and the Americas. The microsatellite diversity and distribution of a Y lineage specific to South America (Q-M19) indicates that certain Amerind populations have been isolated since the initial colonization of the region, suggesting an early onset for tribalization of Native Americans. Age estimates based on Y-chromosome microsatellite diversity place the initial settlement of the American continent at ?14,000 years ago, in relative agreement with the age of well-established archaeological evidence. PMID:12900798

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

    PubMed Central

    Liao, Pei-Chun

    2012-01-01

    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. PMID:23226402

  13. Genetic variability and demographic history of Heliothis virescens (Lepidoptera: Noctuidae) populations from Brazil inferred by mtDNA sequences.

    PubMed

    Albernaz, K C; Silva-Brandăo, K L; Fresia, P; Cônsoli, F L; Omoto, C

    2012-06-01

    Intra- and inter-population genetic variability and the demographic history of Heliothis virescens (F.) populations were evaluated by using mtDNA markers (coxI, coxII and nad6) with samples from the major cotton- and soybean-producing regions in Brazil in the growing seasons 2007/08, 2008/09 and 2009/10. AMOVA indicated low and non-significant genetic structure, regardless of geographical scale, growing season or crop, with most of genetic variation occurring within populations. Clustering analyzes also indicated low genetic differentiation. The haplotype network obtained with combined datasets resulted in 35 haplotypes, with 28 exclusive occurrences, four of them sampled only from soybean fields. The minimum spanning network showed star-shaped structures typical of populations that underwent a recent demographic expansion. The recent expansion was supported by other demographic analyzes, such as the Bayesian skyline plot, the unimodal distribution of paired differences among mitochondrial sequences, and negative and significant values of neutrality tests for the Tajima's D and Fu's F(S) parameters. In addition, high values of haplotype diversity (?) and low values of nucleotide diversity (?), combined with a high number of low frequency haplotypes and values of ?(?)demographic expansion of H. virescens populations in Brazil. This demographic event could be responsible for the low genetic structure currently found; however, haplotypes present uniquely at the same geographic regions and from one specific host plant suggest an initial differentiation among H. virescens populations within Brazil. PMID:22126989

  14. Demographic Divergence History of Pied Flycatcher and Collared Flycatcher Inferred from Whole-Genome Re-sequencing Data

    PubMed Central

    Nadachowska-Brzyska, Krystyna; Burri, Reto; Olason, Pall I.; Kawakami, Takeshi; Smeds, Linnéa; Ellegren, Hans

    2013-01-01

    Profound knowledge of demographic history is a prerequisite for the understanding and inference of processes involved in the evolution of population differentiation and speciation. Together with new coalescent-based methods, the recent availability of genome-wide data enables investigation of differentiation and divergence processes at unprecedented depth. We combined two powerful approaches, full Approximate Bayesian Computation analysis (ABC) and pairwise sequentially Markovian coalescent modeling (PSMC), to reconstruct the demographic history of the split between two avian speciation model species, the pied flycatcher and collared flycatcher. Using whole-genome re-sequencing data from 20 individuals, we investigated 15 demographic models including different levels and patterns of gene flow, and changes in effective population size over time. ABC provided high support for recent (mode 0.3 my, range <0.7 my) species divergence, declines in effective population size of both species since their initial divergence, and unidirectional recent gene flow from pied flycatcher into collared flycatcher. The estimated divergence time and population size changes, supported by PSMC results, suggest that the ancestral species persisted through one of the glacial periods of middle Pleistocene and then split into two large populations that first increased in size before going through severe bottlenecks and expanding into their current ranges. Secondary contact appears to have been established after the last glacial maximum. The severity of the bottlenecks at the last glacial maximum is indicated by the discrepancy between current effective population sizes (20,000–80,000) and census sizes (5–50 million birds) of the two species. The recent divergence time challenges the supposition that avian speciation is a relatively slow process with extended times for intrinsic postzygotic reproductive barriers to evolve. Our study emphasizes the importance of using genome-wide data to unravel tangled demographic histories. Moreover, it constitutes one of the first examples of the inference of divergence history from genome-wide data in non-model species. PMID:24244198

  15. Uptake of HPV Vaccine: Demographics, Sexual History and Values, Parenting Style, and Vaccine Attitudes

    Microsoft Academic Search

    Susan L. Rosenthal; Richard Rupp; Gregory D. Zimet; Heather M. Meza; Melissa L. Loza; Mary B. Short; Paul A. Succop

    2008-01-01

    PurposeTo examine the relationships of demographics, parenting, and vaccine attitudes with the acceptance of the human papillomavirus (HPV) vaccine or to the intent to vaccinate in the next 12 months.

  16. Eytan, R. I. and M. E. Hellberg. 2010. Nuclear and mitochondrial sequence data reveal and conceal different demographic histories and population genetic processes in Caribbean reef

    E-print Network

    Hellberg, Michael E.

    Eytan, R. I. and M. E. Hellberg. 2010. Nuclear and mitochondrial sequence data reveal and conceal different demographic histories and population genetic processes in Caribbean reef fishes. Evolution, in press. Mitochondrial and nuclear sequence data should recover historical demographic events at different

  17. Effects of the demographic transition on the genetic variances and covariances of human life-history traits.

    PubMed

    Bolund, Elisabeth; Hayward, Adam; Pettay, Jenni E; Lummaa, Virpi

    2015-03-01

    The recent demographic transitions to lower mortality and fertility rates in most human societies have led to changes and even quick reversals in phenotypic selection pressures. This can only result in evolutionary change if the affected traits are heritable, but changes in environmental conditions may also lead to subsequent changes in the genetic variance and covariance (the G matrix) of traits. It currently remains unclear if there have been concomitant changes in the G matrix of life-history traits following the demographic transition. Using 300 years of genealogical data from Finland, we found that four key life-history traits were heritable both before and after the demographic transition. The estimated heritabilities allow a quantifiable genetic response to selection during both time periods, thus facilitating continued evolutionary change. Further, the G matrices remained largely stable but revealed a trend for an increased additive genetic variance and thus evolutionary potential of the population after the transition. Our results demonstrate the validity of predictions of evolutionary change in human populations even after the recent dramatic environmental change, and facilitate predictions of how our biology interacts with changing environments, with implications for global public health and demography. PMID:25564932

  18. Genetic structure and demographic history of the endangered and endemic schizothoracine fish Gymnodiptychus pachycheilus in Qinghai-Tibetan Plateau.

    PubMed

    Su, Junhu; Ji, Weihong; Wei, Yanming; Zhang, Yanping; Gleeson, Dianne M; Lou, Zhongyu; Ren, Jing

    2014-08-01

    The endangered schizothoracine fish Gymnodiptychus pachycheilus is endemic to the Qinghai-Tibetan Plateau (QTP), but very little genetic information is available for this species. Here, we accessed the current genetic divergence of G. pachycheilus population to evaluate their distributions modulated by contemporary and historical processes. Population structure and demographic history were assessed by analyzing 1811-base pairs of mitochondrial DNA from 61 individuals across a large proportion of its geographic range. Our results revealed low nucleotide diversity, suggesting severe historical bottleneck events. Analyses of molecular variance and the conventional population statistic FST (0.0435, P = 0.0215) confirmed weak genetic structure. The monophyly of G. pachycheilus was statistically well-supported, while two divergent evolutionary clusters were identified by phylogenetic analyses, suggesting a microgeographic population structure. The consistent scenario of recent population expansion of two clusters was identified based on several complementary analyses of demographic history (0.096 Ma and 0.15 Ma). This genetic divergence and evolutionary process are likely to have resulted from a series of drainage arrangements triggered by the historical tectonic events of the region. The results obtained here provide the first insights into the evolutionary history and genetic status of this little-known fish. PMID:25088592

  19. Reproductive Demographics and Early Life History of the Shovelnose Sturgeon (SCAPHIRHYNCHUS PLATORYNCHUS)

    Microsoft Academic Search

    Robert E. Colombo

    1998-01-01

    Due to the collapse of the historic caviar fisheries in the Volga River and Caspian Sea, the demand on domestically produced caviar has increased. To supply the increased demand, the harvest of the shovelnose sturgeon Scaphirhynchus latorynchus has increased. Because caviar fisheries preferentially harvest females, information regardingthe sexual demographics of these populations is essential for effective fisheries management. To date,

  20. Demographic history and genetic diversity in West Indian Coereba flaveola populations.

    PubMed

    Bellemain, Eva; Gaggiotti, Oscar E; Fahey, Anna; Bermingham, Eldredge; Ricklefs, Robert E

    2012-06-01

    The bananaquit (Coereba flaveola) has been well studied throughout the Caribbean region from a phylogenetic perspective. However, data concerning the population genetics and long-term demography of this bird species are lacking. In this study, we focused on three populations within the Lesser Antilles and one on Puerto Rico and assessed genetic and demographic processes, using five nuclear and two mitochondrial markers. We found that genetic diversity of bananaquits on Puerto Rico exceeds that on the smaller islands (Dominica, Guadeloupe and Grenada); this might reflect either successive founder events from Puerto Rico to Grenada, or more rapid drift in smaller populations subsequent to colonization. Population growth rate estimates showed no evidence of rapid expansion and migration was indicated only between populations from the closest islands of Dominica and Guadeloupe. Overall, our results suggest that a "demographic fission" model, considering only mutation and drift, but without migration, can be applied to these bananaquit populations in the West Indies. PMID:22855326

  1. Demographic and Morphological Perspectives on Life History Evolution and Conservation of New World Monkeys

    Microsoft Academic Search

    Gregory E. Blomquist; Martin M. Kowalewski; Steven R. Leigh

    As an order, primates are distinguished by several features of their life histories from other mammals. These include late achievement of sexual maturity, low female reproductive rates and potentially very long lives (Martin 1990). New World primates present a diverse array of life histories and social organizations (Ross 1991; Garber and Leigh 1997). In this chapter we explore primate life

  2. Effects of Mitochondrial DNA Rate Variation on Reconstruction of Pleistocene Demographic History in a Social Avian Species, Pomatostomus superciliosus

    PubMed Central

    Norman, Janette A.; Blackmore, Caroline J.; Rourke, Meaghan; Christidis, Les

    2014-01-01

    Mitochondrial sequence data is often used to reconstruct the demographic history of Pleistocene populations in an effort to understand how species have responded to past climate change events. However, departures from neutral equilibrium conditions can confound evolutionary inference in species with structured populations or those that have experienced periods of population expansion or decline. Selection can affect patterns of mitochondrial DNA variation and variable mutation rates among mitochondrial genes can compromise inferences drawn from single markers. We investigated the contribution of these factors to patterns of mitochondrial variation and estimates of time to most recent common ancestor (TMRCA) for two clades in a co-operatively breeding avian species, the white-browed babbler Pomatostomus superciliosus. Both the protein-coding ND3 gene and hypervariable domain I control region sequences showed departures from neutral expectations within the superciliosus clade, and a two-fold difference in TMRCA estimates. Bayesian phylogenetic analysis provided evidence of departure from a strict clock model of molecular evolution in domain I, leading to an over-estimation of TMRCA for the superciliosus clade at this marker. Our results suggest mitochondrial studies that attempt to reconstruct Pleistocene demographic histories should rigorously evaluate data for departures from neutral equilibrium expectations, including variation in evolutionary rates across multiple markers. Failure to do so can lead to serious errors in the estimation of evolutionary parameters and subsequent demographic inferences concerning the role of climate as a driver of evolutionary change. These effects may be especially pronounced in species with complex social structures occupying heterogeneous environments. We propose that environmentally driven differences in social structure may explain observed differences in evolutionary rate of domain I sequences, resulting from longer than expected retention times for matriarchal lineages in the superciliosus clade. PMID:25181547

  3. Salivary alpha-amylase during pregnancy: diurnal course and associations with obstetric history, maternal demographics, and mood.

    PubMed

    Giesbrecht, Gerald F; Granger, Douglas A; Campbell, Tavis; Kaplan, Bonnie

    2013-03-01

    Diurnal patterns of salivary alpha amylase (sAA) in pregnant women have not previously been described. The current study employed ecological momentary assessment to examine the association between the diurnal sAA, obstetric history, maternal demographics, and mood during pregnancy. Saliva was self-collected by 83 pregnant women (89% White, age 25.3-43.0 years; mean gestational age 21.9 weeks, range 6-37 weeks; gravida 1-6) at home over three days. Results indicated that current pregnancy (gestational age and fetal sex) and maternal demographics were not related to diurnal sAA. In contrast, a history of previous miscarriage (Parameter = -.17; SE = .05; p < .05) was associated with an atypical diurnal pattern. Even after accounting for obstetric history, trait anxiety (Parameter = .16; SE = .04; p < .001) was associated with increased sAA over the day while chronic levels of fatigue (Parameter = -.06; SE = .03; p < .05) were associated with decreased sAA. In a separate model, we also tested the time varying covariation of sAA and mood. The effects of momentary mood were in contrast to those for trait mood. Both momentary depression (Parameter = .22; SE = .09; p < .01) and vigour/positive mood (Parameter = .12; SE = .04; p < .001) were associated with momentary increases in sAA while momentary anxiety and fatigue were not related to sAA. The findings suggest that basal sAA during pregnancy is sensitive to emotional arousal. Evaluating diurnal patterns of sAA holds promise for advancing understanding of how emotional arousal during pregnancy may affect fetal development. PMID:22315130

  4. Demographic Structure and Evolutionary History of Drosophila ornatifrons (Diptera, Drosophilidae) from Atlantic Forest of Southern Brazil.

    PubMed

    Gustani, Emanuele C; Oliveira, Ana Paula F; Santos, Mateus H; Machado, Luciana P B; Mateus, Rogério P

    2015-04-01

    Drosoph1la ornatifrons of the guarani group (Diptera: Drosophilidae) is found mainly in humid areas of the Atlantic Forest biome, especially in the southern region of Brazil. Historical and contemporary fragmentation events influenced species diversity and distribution in this biome, although the role of paleoclimatic and paleogeographic events remain to be verified. The objective of the present study was to evaluate the demographic structure of D. ornatifrons from collection sites that are remnants of Atlantic Forest in southern Brazil, in order to contribute to the understanding of the processes that affected the patterns of genetic variability in this species. To achieve this goal, we sequenced 51 individuals from nine localities and 64 individuals from six localities for the mitochondrial genes Cytochrome Oxidase I and II, respectively. Our results indicate that D. ornatifrons may have experienced a demographic expansion event from the southernmost locations of its distribution, most likely from those located next to the coast and in fragments of Atlantic Forest inserted in the Pampa biome (South 2 group), towards the interior (South 1 group). This expansion probably started after the last glacial maximum, between 20,000 and 18,000 years ago, and was intensified near the Pleistocene-Holocene transition, around 12,000 years ago, when temperature started to rise. In this work we discuss how the haplotypes found barriers to gene flow and dispersal, influenced by the biogeographic pattern of Atlantic Forest. PMID:25826062

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

    PubMed Central

    2011-01-01

    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. PMID:21682856

  6. Museum DNA reveals the demographic history of the endangered Seychelles warbler

    PubMed Central

    Spurgin, Lewis G; Wright, David J; van der Velde, Marco; Collar, Nigel J; Komdeur, Jan; Burke, Terry; Richardson, David S

    2014-01-01

    The importance of evolutionary conservation – how understanding evolutionary forces can help guide conservation decisions – is widely recognized. However, the historical demography of many endangered species is unknown, despite the fact that this can have important implications for contemporary ecological processes and for extinction risk. Here, we reconstruct the population history of the Seychelles warbler (Acrocephalus sechellensis) – an ecological model species. By the 1960s, this species was on the brink of extinction, but its previous history is unknown. We used DNA samples from contemporary and museum specimens spanning 140 years to reconstruct bottleneck history. We found a 25% reduction in genetic diversity between museum and contemporary populations, and strong genetic structure. Simulations indicate that the Seychelles warbler was bottlenecked from a large population, with an ancestral Ne of several thousands falling to <50 within the last century. Such a rapid decline, due to anthropogenic factors, has important implications for extinction risk in the Seychelles warbler, and our results will inform conservation practices. Reconstructing the population history of this species also allows us to better understand patterns of genetic diversity, inbreeding and promiscuity in the contemporary populations. Our approaches can be applied across species to test ecological hypotheses and inform conservation. PMID:25553073

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

    Microsoft Academic Search

    Andrew J. Dunstan; Peter D. Ward; N. Justin Marshall; Martin Solan

    2011-01-01

    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

  8. Adverse ffects of covert iridovirus infection on life history and demographic parameters of Aedes aegypti

    Microsoft Academic Search

    Carlos F. Marina; Jorge E. Ibarra; Juan I. Arredondo-Jimenez; Ildefonso Fernandez-Salas; Pablo Liedo; Trevor Williams

    2003-01-01

    Sublethal viral infections can cause changes in the body size and demography of insect vectors, with important consequences for population dynamics and the probability that individual mosquitoes will transmit disease. This study examined the effects of covert (sublethal) infection by Invertebrate iridescent virus 6 (IIV-6) on the demography of female Aedes aegypti and the relationship between key life history parameters

  9. Psychosocial Outcomes for Adult Children of Parents with Severe Mental Illnesses: Demographic and Clinical History Predictors

    ERIC Educational Resources Information Center

    Mowbray, Carol T.; Bybee, Deborah; Oyserman, Daphna; MacFarlane, Peter; Bowersox, Nicholas

    2006-01-01

    Children of parents with mental illness are at risk of psychiatric and behavioral problems. Few studies have investigated the psychosocial outcomes of these children in adulthood or the parental psychiatric history variables that predict resilience. From a sample of 379 mothers with serious mental illnesses, 157 women who had at least one adult…

  10. Phylogeography of Chinese cherry (Prunus pseudocerasus Lindl.) inferred from chloroplast and nuclear DNA: insights into evolutionary patterns and demographic history.

    PubMed

    Chen, T; Chen, Q; Luo, Y; Huang, Z-L; Zhang, J; Tang, H-R; Pan, D-M; Wang, X-R

    2015-07-01

    Chinese cherry (Prunus pseudocerasus Lindl.) is a commercially valuable fruit crop in China. In order to obtain new insights into its evolutionary history and provide valuable recommendations for resource conservation, phylogeographic patterns of 26 natural populations (305 total individuals) from six geographic regions were analyzed using chloroplast and nuclear DNA fragments. Low levels of haplotype and nucleotide diversity were found in these populations, especially in landrace populations. It is likely that a combined effect of botanical characteristics impact the effective population size, such as inbreeding mating system, long life span, as well as vegetative reproduction. In addition, strong bottleneck effect caused by domestication, together with founder effect after dispersal and subsequent demographic expansion, might also accelerate the reduction of the genetic variation in landrace populations. Interestingly, populations from Longmen Mountain (LMM) and Daliangshan Mountain (DLSM) exhibited relatively higher levels of genetic diversity, inferring the two historical genetic diversity centers of the species. Moreover, moderate population subdivision was also detected by both chloroplast DNA (GST  = 0.215; NST  = 0.256) and nuclear DNA (GST  = 0.146; NST  = 0.342), respectively. We inferred that the episodes of efficient gene flow through seed dispersal, together with features of long generation cycle and inbreeding mating system, were likely the main contributors causing the observed phylogeographic patterns. Finally, factors that led to the present demographic patterns of populations from these regions and taxonomic varieties were also discussed. PMID:25521479

  11. Life History and Demographic Drivers of Reservoir Competence for Three Tick-Borne Zoonotic Pathogens

    PubMed Central

    Ostfeld, Richard S.; Levi, Taal; Jolles, Anna E.; Martin, Lynn B.; Hosseini, Parviez R.; Keesing, Felicia

    2014-01-01

    Animal and plant species differ dramatically in their quality as hosts for multi-host pathogens, but the causes of this variation are poorly understood. A group of small mammals, including small rodents and shrews, are among the most competent natural reservoirs for three tick-borne zoonotic pathogens, Borrelia burgdorferi, Babesia microti, and Anaplasma phagocytophilum, in eastern North America. For a group of nine commonly-infected mammals spanning >2 orders of magnitude in body mass, we asked whether life history features or surrogates for (unknown) encounter rates with ticks, predicted reservoir competence for each pathogen. Life history features associated with a fast pace of life generally were positively correlated with reservoir competence. However, a model comparison approach revealed that host population density, as a proxy for encounter rates between hosts and pathogens, generally received more support than did life history features. The specific life history features and the importance of host population density differed somewhat between the different pathogens. We interpret these results as supporting two alternative but non-exclusive hypotheses for why ecologically widespread, synanthropic species are often the most competent reservoirs for multi-host pathogens. First, multi-host pathogens might adapt to those hosts they are most likely to experience, which are likely to be the most abundant and/or frequently bitten by tick vectors. Second, species with fast life histories might allocate less to certain immune defenses, which could increase their reservoir competence. Results suggest that of the host species that might potentially be exposed, those with comparatively high population densities, small bodies, and fast pace of life will often be keystone reservoirs that should be targeted for surveillance or management. PMID:25232722

  12. Demographic history, marker variability and genetic differentiation in sandy beach fauna: What is the meaning of low FST's?

    NASA Astrophysics Data System (ADS)

    Bezuidenhout, Karien; Nel, Ronel; Hauser, Lorenz

    2014-10-01

    This note demonstrates the effect of locus variability and demographic history on the estimation of genetic differentiation and its interpretation in terms of ecological connectivity. Cytochrome c oxidase subunit I (COI, mtDNA) sequences of the beach clam Donax serra from four sites along the South African coast were analysed. D. serra showed low COI haplotype diversity (h = 0.30 ± 0.069, 7 haplotypes), suggesting expansion from a small source population into extant habitats. As a consequence, statistical power to measure genetic connectivity was low. The lack of genetic population structure therefore does not necessarily demonstrate high connectivity. Although COI has been used successfully to identify species and populations isolated for prolonged periods of time, lack of differentiation has to be interpreted with caution, especially in terms of extant patterns of connectivity.

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

    PubMed Central

    2014-01-01

    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. PMID:25016306

  14. Blacktip reef sharks, Carcharhinus melanopterus, have high genetic structure and varying demographic histories in their Indo-Pacific range.

    PubMed

    Vignaud, Thomas M; Mourier, Johann; Maynard, Jeffrey A; Leblois, Raphael; Spaet, Julia; Clua, Eric; Neglia, Valentina; Planes, Serge

    2014-11-01

    For free-swimming marine species like sharks, only population genetics and demographic history analyses can be used to assess population health/status as baseline population numbers are usually unknown. We investigated the population genetics of blacktip reef sharks, Carcharhinus melanopterus; one of the most abundant reef-associated sharks and the apex predator of many shallow water reefs of the Indian and Pacific Oceans. Our sampling includes 4 widely separated locations in the Indo-Pacific and 11 islands in French Polynesia with different levels of coastal development. Four-teen microsatellite loci were analysed for samples from all locations and two mitochondrial DNA fragments, the control region and cytochrome b, were examined for 10 locations. For microsatellites, genetic diversity is higher for the locations in the large open systems of the Red Sea and Australia than for the fragmented habitat of the smaller islands of French Polynesia. Strong significant structure was found for distant locations with FST values as high as ~0.3, and a smaller but still significant structure is found within French Polynesia. Both mitochondrial genes show only a few mutations across the sequences with a dominant shared haplotype in French Polynesia and New Caledonia suggesting a common lineage different to that of East Australia. Demographic history analyses indicate population expansions in the Red Sea and Australia that may coincide with sea level changes after climatic events. Expansions and flat signals are indicated for French Polynesia as well as a significant recent bottleneck for Moorea, the most human-impacted lagoon of the locations in French Polynesia. PMID:25251515

  15. Utilizing Spatial Demographic and Life History Variation to Optimize Sustainable Yield of a Temperate Sex-Changing Fish

    PubMed Central

    Hamilton, Scott L.; Wilson, Jono R.; Ben-Horin, Tal; Caselle, Jennifer E.

    2011-01-01

    Fish populations vary geographically in demography and life history due to environmental and ecological processes and in response to exploitation. However, population dynamic models and stock assessments, used to manage fisheries, rarely explicitly incorporate spatial variation to inform management decisions. Here, we describe extensive geographic variation in several demographic and life history characteristics (e.g., size structure, growth, survivorship, maturation, and sex change) of California sheephead (Semicossyphus pulcher), a temperate rocky reef fish targeted by recreational and commercial fisheries. Fish were sampled from nine locations throughout southern California in 2007–2008. We developed a dynamic size and age-structured model, parameterized separately for each location, to assess the potential cost or benefit in terms of fisheries yield and conservation objectives of changing minimum size limits and/or fishing mortality rates (compared to the status quo). Results indicate that managing populations individually, with location-specific regulations, could increase yield by over 26% while maintaining conservative levels of spawning biomass. While this local management approach would be challenging to implement in practice, we found statistically similar increases in yield could be achieved by dividing southern California into two separate management regions, reflecting geographic similarities in demography. To maximize yield, size limits should be increased by 90 mm in the northern region and held at current levels in the south. We also found that managing the fishery as one single stock (the status quo), but with a size limit 50 mm greater than the current regulations, could increase overall fishery yield by 15%. Increases in size limits are predicted to enhance fishery yield and may also have important ecological consequences for the predatory role of sheephead in kelp forests. This framework for incorporating demographic variation into fisheries models can be exported generally to other species and may aid in identifying the appropriate spatial scales for fisheries management. PMID:21915353

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

    PubMed Central

    2014-01-01

    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. PMID:24661555

  17. Malthus in state space: Macro economic-demographic relations in English history, 1540 to 1870

    Microsoft Academic Search

    Ronald Lee; Michael Anderson

    2002-01-01

    . The history of preindustrial Europe provides an opportunity to examine the causes and consequences of population change\\u000a at a macro level. However, serious statistical problems arise from the endogeneity of all observed variables in a Malthusian\\u000a system (fertility, mortality, population size, and real wages), and from unobserved influences such as shifts in the demand\\u000a for labor and variations in

  18. AFRICAN GENETIC DIVERSITY: Implications for Human Demographic History, Modern Human Origins, and Complex Disease Mapping

    PubMed Central

    Campbell, Michael C.; Tishkoff, Sarah A.

    2010-01-01

    Comparative studies of ethnically diverse human populations, particularly in Africa, are important for reconstructing human evolutionary history and for understanding the genetic basis of phenotypic adaptation and complex disease. African populations are characterized by greater levels of genetic diversity, extensive population substructure, and less linkage disequilibrium (LD) among loci compared to non-African populations. Africans also possess a number of genetic adaptations that have evolved in response to diverse climates and diets, as well as exposure to infectious disease. This review summarizes patterns and the evolutionary origins of genetic diversity present in African populations, as well as their implications for the mapping of complex traits, including disease susceptibility. PMID:18593304

  19. [Mitochondrial DNA sequence variation, demographic history, and population structure of Amur sturgeon Acipenser schrenckii Brandt, 1869].

    PubMed

    Shedko, S V; Miroshnichenko, I L; Nemkova, G A; Koshelev, V N; Shedko, M B

    2015-02-01

    The variability of the mtDNA control region (D-loop) was examined in Amur sturgeon endemic to the Amur River. This species is also classified as critically endangered by the IUCN Red List of Threatened species. Sequencing of 796- to 812-bp fragments of the D-loop in 112 sturgeon collected in the Lower Amur revealed 73 different genotypes. The sample was characterized by a high level of haplotypic (0.976) and nucleotide (0.0194) diversity. The identified haplotypes split into two well-defined monophyletic groups, BG (n = 39) and SM (n = 34), differing (HKY distance) on average by 3.41% of nucleotide positions upon an average level of intragroup differences of 0.54 and 1.23%, respectively. Moreover, the haplotypes of the SM groups differed by the presence of a 13-14 bp deletion. Most ofthe samples (66 out of 112) carried BG haplotypes. Overall, the pattern of pairwise nucleotide differences and the results of neutrality tests, as well as the results of tests for compliance with the model of sudden demographic expansion or with the model of exponential growth pointed to a past significant increase in the number of Amur sturgeon, which was most clearly manifested in the analysis of data on the BG haplogroup. The constructed Bayesian skyline plots showed that this growth began about 18 to 16 thousand years ago. At present, the effective size of the strongly reduced (due to overharvesting) population of Amur sturgeon may be equal to or even lower than it was before the beginning of this growth during the Last Glacial Maximum. The presence in the mitochondrial gene pool ofAmur sturgeon of two haplogroups, their unequal evolutionary dynamics, and, judging by scanty data, their unequal representation in the Russian and Chinese parts of the Amur River basin point to the possible existence of at least two distinct populations of Amur sturgeon in the past. PMID:25966586

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

    PubMed Central

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

    2011-01-01

    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

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

    PubMed

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

    2011-01-01

    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

  2. Genetic variation and demographic history of the Haplochromis laparogramma group of Lake Victoria--An analysis based on SINEs and mitochondrial DNA

    E-print Network

    Genetic variation and demographic history of the Haplochromis laparogramma group of Lake Victoria More than 500 endemic haplochromine cichlid species inhabit Lake Victoria. This striking species and population structure of closely related Lake Victoria cichlids and in showing the importance of applying

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

    PubMed Central

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

    2012-01-01

    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

  4. Demographic patterns of Ferocactus cylindraceus in relation to substrate age and grazing history

    USGS Publications Warehouse

    Bowers, Janice E.

    1997-01-01

    Three subpopulations of Ferocactus cylindraceus, a short-columnar cactus of the Sonoran and Mojave deserts, were sampled in Grand Canyon, Arizona, USA, at sites representing a range of substrate ages and different grazing histories. Age-height relations were determined from annual growth, then used to estimate probable year of establishment for each cohort. Eight years between 1944 and 1992 were especially favorable for establishment. Six of these 8 years coincided with El Nino-Southern Oscillation conditions, indicating that as for many woody plants in arid regions, somewhat unusual climatic conditions are necessary if populations are to replace themselves. Comparison of age structures showed that established and developing populations have somewhat different dynamics in that the rate of population increase was slowest on the youngest terrace. On the ancient terraces, about half the plants were less than 25 years old. Plants older than 40 years were few; however the oldest plants in the study (about 49 years) grew on the ancient terraces. On the recent terrace, 76% of the subpopulation was 25 years or younger, and the oldest living plant was about 36 years of age. The age structures of subpopulations on grazed and ungrazed sites also differed markedly. On ungrazed sites, subpopulations were more or less at equilibrium, with enough young plants to replace old ones as they died. In contrast, the subpopulation on the grazed site was in a state of marked disequilibrium. Grazing before 1981 largely extirpated a palatable subshrub that was probably an important nurse plant. Until the shrub population at Indian Canyon recovers from decades of burro grazing, a rebound in E cylindraceus establishment is not to be expected.

  5. Comparative demography of an epiphytic lichen: support for general life history patterns and solutions to common problems in demographic parameter estimation.

    PubMed

    Shriver, Robert K; Cutler, Kerry; Doak, Daniel F

    2012-09-01

    Lichens are major components in many terrestrial ecosystems, yet their population ecology is at best only poorly understood. Few studies have fully quantified the life history or demographic patterns of any lichen, with particularly little attention to epiphytic species. We conducted a 6-year demographic study of Vulpicida pinastri, an epiphytic foliose lichen, in south-central Alaska. After testing multiple size-structured functions to describe patterns in each V. pinastri demographic rate, we used the resulting estimates to construct a stochastic demographic model for the species. This model development led us to propose solutions to two general problems in construction of demographic models for many taxa: how to simply but accurately characterize highly skewed growth rates, and how to estimate recruitment rates that are exceptionally difficult to directly observe. Our results show that V. pinastri has rapid and variable growth and, for small individuals, low and variable survival, but that these traits are coupled with considerable longevity (e.g., >50 years mean future life span for a 4-cm(2) thallus) and little deviation of the stochastic population growth rate from the deterministic expectation. Comparisons of the demographic patterns we found with those of other lichen studies suggest that their relatively simple architecture may allow clearer generalities about growth patterns for lichens than for other taxa, and that the expected pattern of faster growth rates for epiphytic species is substantiated. PMID:22453647

  6. 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

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

    2011-01-01

    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. PMID:22164307

  7. High-Dimensional Coexistence of Temperate Tree Species: Functional Traits, Demographic Rates, Life-History Stages, and Their Physical Context

    PubMed Central

    McMahon, Sean M.; Metcalf, Charlotte J. E.; Woodall, Christopher W.

    2011-01-01

    Theoretical models indicate that trade-offs between growth and survival strategies of tree species can lead to coexistence across life history stages (ontogeny) and physical conditions experienced by individuals. There exist predicted physiological mechanisms regulating these trade-offs, such as an investment in leaf characters that may increase survival in stressful environments at the expense of investment in bole or root growth. Confirming these mechanisms, however, requires that potential environmental, ontogenetic, and trait influences are analyzed together. Here, we infer growth and mortality of tree species given size, site, and light characteristics from forest inventory data from Wisconsin to test hypotheses about growth-survival trade-offs given species functional trait values under different ontogenetic and environmental states. A series of regression analyses including traits and rates their interactions with environmental and ontogenetic stages supported the relationships between traits and vital rates expected from the expectations from tree physiology. A combined model including interactions between all variables indicated that relationships between demographic rates and functional traits supports growth-survival trade-offs and their differences across species in high-dimensional niche space. The combined model explained 65% of the variation in tree growth and supports a concept of community coexistence similar to Hutchinson's n-dimensional hypervolume and not a low-dimensional niche model or neutral model. PMID:21305020

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

    PubMed Central

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

    2012-01-01

    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. PMID:22558439

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

    PubMed

    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

    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

  10. Evolutionary origin and demographic history of an ancient conifer (Juniperus microsperma) in the Qinghai-Tibetan Plateau.

    PubMed

    Shang, Hui-Ying; Li, Zhong-Hu; Dong, Miao; Adams, Robert P; Miehe, Georg; Opgenoorth, Lars; Mao, Kang-Shan

    2015-01-01

    All Qinghai-Tibetan Plateau (QTP) endemic species are assumed to have originated recently, although very rare species most likely diverged early. These ancient species provide an excellent model to examine the origin and evolution of QTP endemic plants in response to the QTP uplifts and the climate changes that followed in this high altitude region. In this study, we examined these hypotheses by employing sequence variation from multiple nuclear and chloroplast DNA of 239 individuals of Juniperus microsperma and its five congeners. Both phylogenetic and population genetic analyses revealed that J. microsperma diverged from its sister clade comprising two species with long isolation around the Early Miocene, which corresponds to early QTP uplift. Demographic modeling and coalescent tests suggest that J. microsperma experienced an obvious bottleneck event during the Quaternary when the global climate greatly oscillated. The results presented here support the hypotheses that the QTP uplifts and Quaternary climate changes played important roles in shaping the evolutionary history of this rare juniper. PMID:25977142

  11. Speciation, population structure, and demographic history of the Mojave Fringe-toed Lizard (Uma scoparia), a species of conservation concern

    PubMed Central

    Gottscho, Andrew D; Marks, Sharyn B; Jennings, W Bryan

    2014-01-01

    The North American deserts were impacted by both Neogene plate tectonics and Quaternary climatic fluctuations, yet it remains unclear how these events influenced speciation in this region. We tested published hypotheses regarding the timing and mode of speciation, population structure, and demographic history of the Mojave Fringe-toed Lizard (Uma scoparia), a sand dune specialist endemic to the Mojave Desert of California and Arizona. We sampled 109 individual lizards representing 22 insular dune localities, obtained DNA sequences for 14 nuclear loci, and found that U. scoparia has low genetic diversity relative to the U. notata species complex, comparable to that of chimpanzees and southern elephant seals. Analyses of genotypes using Bayesian clustering algorithms did not identify discrete populations within U. scoparia. Using isolation-with-migration (IM) models and a novel coalescent-based hypothesis testing approach, we estimated that U. scoparia diverged from U. notata in the Pleistocene epoch. The likelihood ratio test and the Akaike Information Criterion consistently rejected nested speciation models that included parameters for migration and population growth of U. scoparia. We reject the Neogene vicariance hypothesis for the speciation of U. scoparia and define this species as a single evolutionarily significant unit for conservation purposes. PMID:25360285

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

    PubMed Central

    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

    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

  13. Speciation, population structure, and demographic history of the Mojave Fringe-toed Lizard (Uma scoparia), a species of conservation concern.

    PubMed

    Gottscho, Andrew D; Marks, Sharyn B; Jennings, W Bryan

    2014-06-01

    The North American deserts were impacted by both Neogene plate tectonics and Quaternary climatic fluctuations, yet it remains unclear how these events influenced speciation in this region. We tested published hypotheses regarding the timing and mode of speciation, population structure, and demographic history of the Mojave Fringe-toed Lizard (Uma scoparia), a sand dune specialist endemic to the Mojave Desert of California and Arizona. We sampled 109 individual lizards representing 22 insular dune localities, obtained DNA sequences for 14 nuclear loci, and found that U. scoparia has low genetic diversity relative to the U. notata species complex, comparable to that of chimpanzees and southern elephant seals. Analyses of genotypes using Bayesian clustering algorithms did not identify discrete populations within U. scoparia. Using isolation-with-migration (IM) models and a novel coalescent-based hypothesis testing approach, we estimated that U. scoparia diverged from U. notata in the Pleistocene epoch. The likelihood ratio test and the Akaike Information Criterion consistently rejected nested speciation models that included parameters for migration and population growth of U. scoparia. We reject the Neogene vicariance hypothesis for the speciation of U. scoparia and define this species as a single evolutionarily significant unit for conservation purposes. PMID:25360285

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

    PubMed

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

    2014-07-01

    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

  15. A life prediction model for welded joints under multiaxial variable amplitude loading histories

    Microsoft Academic Search

    Yung-Li Lee; Tana Tjhung; Algernon Jordan

    2007-01-01

    This paper describes a simple damage model for fatigue life predictions of welded joints under nonproportional, constant, and variable amplitude loading histories. This model, an extension of Sonsino’s effective equivalent stress amplitude method, consists of four material parameters accounting for the severity of nonproportional loading paths, the material’s susceptibility to nonproportional hardening, the material’s fatigue life under shear versus normal

  16. Divorcing the Late Upper Palaeolithic demographic histories of mtDNA haplogroups M1 and U6 in Africa

    PubMed Central

    2012-01-01

    Background A Southwest Asian origin and dispersal to North Africa in the Early Upper Palaeolithic era has been inferred in previous studies for mtDNA haplogroups M1 and U6. Both haplogroups have been proposed to show similar geographic patterns and shared demographic histories. Results We report here 24 M1 and 33 U6 new complete mtDNA sequences that allow us to refine the existing phylogeny of these haplogroups. The resulting phylogenetic information was used to genotype a further 131 M1 and 91 U6 samples to determine the geographic spread of their sub-clades. No southwest Asian specific clades for M1 or U6 were discovered. U6 and M1 frequencies in North Africa, the Middle East and Europe do not follow similar patterns, and their sub-clade divisions do not appear to be compatible with their shared history reaching back to the Early Upper Palaeolithic. The Bayesian Skyline Plots testify to non-overlapping phases of expansion, and the haplogroups’ phylogenies suggest that there are U6 sub-clades that expanded earlier than those in M1. Some M1 and U6 sub-clades could be linked with certain events. For example, U6a1 and M1b, with their coalescent ages of ~20,000–22,000 years ago and earliest inferred expansion in northwest Africa, could coincide with the flourishing of the Iberomaurusian industry, whilst U6b and M1b1 appeared at the time of the Capsian culture. Conclusions Our high-resolution phylogenetic dissection of both haplogroups and coalescent time assessments suggest that the extant main branching pattern of both haplogroups arose and diversified in the mid-later Upper Palaeolithic, with some sub-clades concomitantly with the expansion of the Iberomaurusian industry. Carriers of these maternal lineages have been later absorbed into and diversified further during the spread of Afro-Asiatic languages in North and East Africa. PMID:23206491

  17. Hypermobile joints

    MedlinePLUS

    ... hypermobile joints have an increased risk for joint dislocation and other problems. Extra care may be needed ... the joint? Is there any history of joint dislocation, difficulty walking, or difficulty using the arms? Further ...

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

    PubMed

    Hung, C-M; Zink, R M

    2014-07-01

    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

  19. Joint morphology in the insect leg: evolutionary history inferred from Notch loss-of-function phenotypes in Drosophila

    PubMed Central

    Tajiri, Reiko; Misaki, Kazuyo; Yonemura, Shigenobu; Hayashi, Shigeo

    2011-01-01

    Joints permit efficient locomotion, especially among animals with a rigid skeleton. Joint morphologies vary in the body of individual animals, and the shapes of homologous joints often differ across species. The diverse locomotive behaviors of animals are based, in part, on the developmental and evolutionary history of joint morphogenesis. We showed previously that strictly coordinated cell-differentiation and cell-movement events within the epidermis sculpt the interlocking ball-and-socket joints in the adult Drosophila tarsus (distal leg). Here, we show that the tarsal joints of various insect species can be classified into three types: ball-and-socket, side-by-side and uniform. The last two probably result from joint formation without the cell-differentiation step, the cell-movement step, or both. Similar morphological variations were observed in Drosophila legs when Notch function was temporarily blocked during joint formation, implying that the independent acquisition of cell differentiation and cell movement underlay the elaboration of tarsal joint morphologies during insect evolution. These results provide a framework for understanding how the seemingly complex morphology of the interlocking joint could have developed during evolution by the addition of simple developmental modules: cell differentiation and cell movement. PMID:21989911

  20. Patterns of nucleotide sequence variation in ICAM1 and TNF genes in twelve ethnic groups of India: roles of demographic history and natural selection.

    PubMed

    Sengupta, Sanghamitra; Farheen, Shabana; Mukherjee, Neelanjana; Majumder, Partha P

    2007-12-01

    We have studied DNA sequence variation in and around the genes ICAM1 and TNF, which play functional and correlated roles in inflammatory processes and immune cell responses, in 12 diverse ethnic groups of India, with a view to investigating the relative roles of demographic history and natural selection in shaping the observed patterns of variation. The total numbers of single nucleotide polymorphisms (SNPs) detected at the ICAM1 and TNF loci were 29 and 12, respectively. Haplotype and allele frequencies differed significantly across populations. The site frequency spectra at these loci were significantly different from those expected under neutrality, and showed an excess of intermediate-frequency variants consistent with balancing selection. However, as expected under balancing selection, there was no significant reduction of F(ST) values compared to neutral autosomal loci. Mismatch distributions were consistent with population expansion for both loci. On the other hand, the phylogenetic network among haplotypes for the TNF locus was similar to expectations under population expansion, while that for the ICAM1 was as expected under balancing selection. Nucleotide diversity at the ICAM1 locus was an order of magnitude lower in the promoter region, compared to the introns or exons, but no such difference was noted for the TNF gene. Thus, we conclude that the pattern of nucleotide variation in these genes has been modulated by both demographic history and selection. This is not surprising in view of the known allelic associations of several polymorphisms in these genes with various diseases, both infectious and noninfectious. PMID:18305342

  1. 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

    Alvarado-Esquivel, Cosme; Sánchez-Anguiano, Luis Francisco; Arnaud-Gil, Carlos Alberto; Hernández-Tinoco, Jesús; Molina-Espinoza, Luis Fernando; Rábago-Sánchez, Elizabeth

    2014-01-01

    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. PMID:24711751

  2. Life-history and demographic variation in an alpine specialist at the latitudinal extremes of the range

    Microsoft Academic Search

    Scott Wilson; Kathy Martin

    2011-01-01

    Alpine environments are unique systems to examine variation in life-history strategies because temperature and seasonality\\u000a are similar across broad latitudinal gradients. We studied the life-history strategies, demography and population growth of\\u000a white-tailed ptarmigan Lagopus leucura, an alpine specialist, at the latitudinal extremes of the range in the Yukon (YK, studied from 2004 to 2008) and Colorado\\u000a (CO, 1987–1996). The two

  3. Did glacial advances during the Pleistocene influence differently the demographic histories of benthic and pelagic Antarctic shelf fishes? – Inferences from intraspecific mitochondrial and nuclear DNA sequence diversity

    PubMed Central

    Janko, Karel; Lecointre, Guillaume; DeVries, Arthur; Couloux, Arnaud; Cruaud, Corinne; Marshall, Craig

    2007-01-01

    Background Circum-Antarctic waters harbour a rare example of a marine species flock – the Notothenioid fish, most species of which are restricted to the continental shelf. It remains an open question as to how they survived Pleistocene climatic fluctuations characterised by repeated advances of continental glaciers as far as the shelf break that probably resulted in a loss of habitat for benthic organisms. Pelagic ecosystems, on the other hand, might have flourished during glacial maxima due to the northward expansion of Antarctic polar waters. In order to better understand the role of ecological traits in Quaternary climatic fluctuations, we performed demographic analyses of populations of four fish species from the tribe Trematominae, including both fully benthic and pelagic species using the mitochondrial cytochrome b gene and an intron from the nuclear S7 gene. Results Nuclear and cytoplasmic markers showed differences in the rate and time of population expansions as well as the likely population structure. Neutrality tests suggest that such discordance comes from different coalescence dynamics of each marker, rather than from selective pressure. Demographic analyses based on intraspecific DNA diversity suggest a recent population expansion in both benthic species, dated by the cyt b locus to the last glacial cycle, whereas the population structure of pelagic feeders either did not deviate from a constant-size model or indicated that the onset of the major population expansion of these species by far predated those of the benthic species. Similar patterns were apparent even when comparing previously published data on other Southern Ocean organisms, but we observed considerable heterogeneity within both groups with regard to the onset of major demographic events and rates. Conclusion Our data suggest benthic and pelagic species reacted differently to the Pleistocene ice-sheet expansions that probably significantly reduced the suitable habitat for benthic species. However, the asynchronous timing of major demographic events observed in different species within both "ecological guilds", imply that the species examined here may have different population and evolutionary histories, and that more species should be analysed in order to more precisely assess the role of life history in the response of organisms to climatic changes. PMID:17997847

  4. THE JOINT INFLUENCE OF INTERACTION HISTORY AND TIME HORIZON ON VENTURE-CAPITALIST\\/NEW-VENTURE TEAM COOPERATION

    Microsoft Academic Search

    Terje Berg-Utby; Roger Sřrheim; Truls Erikson

    2007-01-01

    This paper investigates post investment cooperation between new venture teams and venture capitalists a propos the longevity of the relationship. Due to the structure of venture capital funds, the authors of this piece argue that the joint effect of the history of interaction between the parties, and time horizon of the relationship, is an especially important determinant of the cooperation

  5. Pragmatic Perspective on Conservation Genetics and Demographic History of the Last Surviving Population of Kashmir Red Deer (Cervus elaphus hanglu) in India

    PubMed Central

    Mukesh; Kumar, Ved P.; Sharma, Lalit K.; Shukla, Malay; Sathyakumar, Sambandam

    2015-01-01

    The hangul (Cervus elaphus hanglu) is of great conservation concern because it represents the easternmost and only hope for an Asiatic survivor of the red deer species in the Indian subcontinent. Despite the rigorous conservation efforts of the Department of Wildlife Protection in Jammu & Kashmir, the hangul population has experienced a severe decline in numbers and range contraction in the past few decades. The hangul population once abundant in the past has largely become confined to the Dachigam landscape, with a recent population estimate of 218 individuals. We investigated the genetic variability and demographic history of the hangul population and found that it has shown a relatively low diversity estimates when compared to other red deer populations of the world. Neutrality tests, which are used to evaluate demographic effects, did not support population expansion, and the multimodal pattern of mismatch distribution indicated that the hangul population is under demographic equilibrium. Furthermore, the hangul population did not exhibit any signature of bottleneck footprints in the past, and Coalescent Bayesian Skyline plot analysis revealed that the population had not experienced any dramatic changes in the effective population size over the last several thousand years. We observed a strong evidence of sub-structuring in the population, wherein the majority of individuals were assigned to different clusters in Bayesian cluster analysis. Population viability analysis demonstrated insignificant changes in the mean population size, with a positive growth rate projected for the next hundred years. We discuss the phylogenetic status of hangul for the first time among the other red deer subspecies of the world and strongly recommend to upgrade hangul conservation status under IUCN that should be discrete from the other red deer subspecies of the world to draw more conservation attention from national and international bodies. PMID:25671567

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

    PubMed Central

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

    2013-01-01

    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. PMID:24187588

  7. Multilocus Patterns of Nucleotide Diversity, Linkage Disequilibrium and Demographic History of Norway Spruce [Picea abies (L.) Karst

    PubMed Central

    Heuertz, Myriam; De Paoli, Emanuele; Källman, Thomas; Larsson, Hanna; Jurman, Irena; Morgante, Michele; Lascoux, Martin; Gyllenstrand, Niclas

    2006-01-01

    DNA polymorphism at 22 loci was studied in an average of 47 Norway spruce [Picea abies (L.) Karst.] haplotypes sampled in seven populations representative of the natural range. The overall nucleotide variation was limited, being lower than that observed in most plant species so far studied. Linkage disequilibrium was also restricted and did not extend beyond a few hundred base pairs. All populations, with the exception of the Romanian population, could be divided into two main domains, a Baltico–Nordic and an Alpine one. Mean Tajima's D and Fay and Wu's H across loci were both negative, indicating the presence of an excess of both rare and high-frequency-derived variants compared to the expected frequency spectrum in a standard neutral model. Multilocus neutrality tests based on D and H led to the rejection of the standard neutral model and exponential growth in the whole population as well as in the two main domains. On the other hand, in all three cases the data are compatible with a severe bottleneck occurring some hundreds of thousands of years ago. Hence, demographic departures from equilibrium expectations and population structure will have to be accounted for when detecting selection at candidate genes and in association mapping studies, respectively. PMID:17057229

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

    PubMed

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

    2014-05-01

    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

  9. Evolutionary history of a widespread Indo-Pacific goby: the role of Pleistocene sea-level changes on demographic contraction/expansion dynamics.

    PubMed

    Hoareau, Thierry Bernard; Boissin, Emilie; Berrebi, Patrick

    2012-01-01

    Compared to endemics, widespread species are of particular interest to retrace recent evolutionary history. These species have a large population size which provides a clearer genetic signature of past events. Moreover, their wide geographic range increases the potential occurrence of evolutionary events (expansion, divergence, etc.). Here, we used several coalescent-based methods to disentangle the evolutionary history of a widespread amphidromous goby (Sicyopterus lagocephalus), in the light of sea-level variations during the Pleistocene. Using 75 samples recovered from three biogeographic regions (Western Indian Ocean, Melanesia and Polynesia), we analysed a portion of the cytochromeb gene and confirmed three major haplogroups, each specific to a region. Furthermore, we found that: (1) the Melanesian haplogroup was the oldest while the two peripheral regions hosted daughter haplogroups; (2) two centrifugal colonisation events occurred from Melanesia to the periphery, each synchronised with periods of strong paleo-ENSO episodes; (3) the demographic contraction-expansion events were linked to Pleistocene sea-level changes; (4) Melanesia and Polynesia acted as efficient refuges during the Last Glacial Maximum. These results highlight the importance of studying widespread species to better understand the role of climate changes and paleo-oceanography on the evolution of biodiversity. PMID:22037473

  10. When competition eclipses cooperation: an event history analysisof joint venture failure

    Microsoft Academic Search

    Seung Ho Park; Michael V. Russo

    1996-01-01

    Why do so many joint ventures fail? Despite the fact that their success is the exception rather than the rule, the literature on why joint venture performance has been so poor remains fragmentary. We address this issue, adopting a transaction-cost economics perspective and modeling joint ventures as governance structures that blend the advantages and drawbacks of both markets and hierarchies.

  11. Human paternal and maternal demographic histories: insights from high-resolution Y chromosome and mtDNA sequences

    PubMed Central

    2014-01-01

    Background Comparisons of maternally-inherited mitochondrial DNA (mtDNA) and paternally-inherited non-recombining Y chromosome (NRY) variation have provided important insights into the impact of sex-biased processes (such as migration, residence pattern, and so on) on human genetic variation. However, such comparisons have been limited by the different molecular methods typically used to assay mtDNA and NRY variation (for example, sequencing hypervariable segments of the control region for mtDNA vs. genotyping SNPs and/or STR loci for the NRY). Here, we report a simple capture array method to enrich Illumina sequencing libraries for approximately 500 kb of NRY sequence, which we use to generate NRY sequences from 623 males from 51 populations in the CEPH Human Genome Diversity Panel (HGDP). We also obtained complete mtDNA genome sequences from the same individuals, allowing us to compare maternal and paternal histories free of any ascertainment bias. Results We identified 2,228 SNPs in the NRY sequences and 2,163 SNPs in the mtDNA sequences. Our results confirm the controversial assertion that genetic differences between human populations on a global scale are bigger for the NRY than for mtDNA, although the differences are not as large as previously suggested. More importantly, we find substantial regional variation in patterns of mtDNA versus NRY variation. Model-based simulations indicate very small ancestral effective population sizes (<100) for the out-of-Africa migration as well as for many human populations. We also find that the ratio of female effective population size to male effective population size (Nf/Nm) has been greater than one throughout the history of modern humans, and has recently increased due to faster growth in Nf than Nm. Conclusions The NRY and mtDNA sequences provide new insights into the paternal and maternal histories of human populations, and the methods we introduce here should be widely applicable for further such studies. PMID:25254093

  12. Demographic Data

    Cancer.gov

    Close Window State Cancer Profiles Quick Reference Guides ? Quick Reference Guides Index Demographic Data Send to Printer Text description of this image. Site Home Policies Accessibility Viewing Files FOIA Contact Us U.S. Department of Health and Human

  13. Demographic Research

    NSDL National Science Digital Library

    Demographic Research is a newly launched, peer-reviewed online journal of the population sciences published by the Max Planck Institute for Demographic Research in Rostock, Germany. The first article in Volume One (covering May 1, 1999 to December 31, 1999) has recently been posted: Cancer Rates over Age, Time, and Place: Insights from Stochastic Models of Heterogeneous Populations by James W. Vaupel and Anatoli I. Yashin. Articles are available in both HTML and .pdf formats. The Website provides detailed information about the journal's purpose, mission, submission guidelines, and review process.

  14. The manifestations and natural history of spondylo-epi-metaphyseal dysplasia with joint laxity.

    PubMed

    Beighton, P; Gericke, G; Kozlowski, K; Grobler, L

    1984-10-01

    Spondylo-epi-metaphyseal dysplasia with joint laxity (SEMDJL) is characterized by severe dwarfism, articular hypermobility and progressive spinal malalignment. The clinical manifestations of 18 affected persons in 13 families of the Afrikans-speaking community of South Africa have been analysed and it has become evident that survival into adulthood is unusual. SEMDJL is inherited as an autosomal recessive trait. PMID:6499247

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

    PubMed

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

    2014-07-01

    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

  16. 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

    2010-01-01

    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. PMID:20525191

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

    USGS Publications Warehouse

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

    2004-01-01

    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.

  18. Dounreay PFR irradiation history for the joint US\\/UK actinide sample exposures

    Microsoft Academic Search

    S. Raman; B. D. Murphy; C. W. Jr. Nestor

    1995-01-01

    The operating history of the Dounreay Prototype Fast Reactor is presented to the extent that it is relevant to the irradiation of actinide specimens that were subsequently analyzed at Oak Ridge National Laboratory (ORNL). Three fuel pins with actinide samples were irradiated from July 1982 to July 1988 and returned to ORNL for analysis. They contained isotopes of elements from

  19. Dounreay PFR irradiation history for the joint US/UK actinide sample exposures

    SciTech Connect

    Raman, S.; Murphy, B.D.; Nestor, C.W. Jr. [and others

    1995-07-01

    The operating history of the Dounreay Prototype Fast Reactor is presented to the extent that it is relevant to the irradiation of actinide specimens that were subsequently analyzed at Oak Ridge National Laboratory (ORNL). Three fuel pins with actinide samples were irradiated from July 1982 to July 1988 and returned to ORNL for analysis. They contained isotopes of elements from thorium to curium. The times when each of these fuel pins were in the reactor core are described as are the operating power levels and neutron spectra. The appendices give daily power levels of the reactor as well as six-group neutron energy spectra for various times and axial positions in the core.

  20. A joint history of the nature of genetic variation and the nature of schizophrenia.

    PubMed

    Kendler, K S

    2015-02-01

    This essay traces the history of concepts of genetic variation and schizophrenia from Darwin and Mendel to the present. For Darwin, the important form of genetic variation for evolution is continuous in nature and small in effect. Biometricians led by Pearson agreed and developed statistical genetic approaches utilizing trait correlations in relatives. Mendel studied discontinuous traits and subsequent Mendelians, led by Bateson, assumed that important genetic variation was large in effect producing discontinuous phenotypes. Although biometricians studied 'insanity', schizophrenia genetics under Kraepelin and Rüdin utilized Mendelian approaches congruent with their anatomical-clinical disease model of dementia praecox. Fisher showed, assuming many genes of small effect, Mendelian and Biometrical models were consilient. Echoing prior conflicts, psychiatric genetics since then has utilized both biometrical models, largely in twins, and Mendelian models, based on advancing molecular techniques. In 1968, Gottesman proposed a polygenic model for schizophrenia based on a threshold version of Fisher's theory. Since then, rigorous studies of the schizophrenia spectrum suggest that genetic risk for schizophrenia is more likely continuous than categorical. The last 5 years has seen increasingly convincing evidence from genome-wide association study (GWAS) and sequencing that genetic risk for schizophrenia is largely polygenic, and congruent with Fisher's and Gottesman's models. The gap between biometrical and molecular Mendelian models for schizophrenia has largely closed. The efforts to ground a categorical biomedical model of schizophrenia in Mendelian genetics have failed. The genetic risk for schizophrenia is widely distributed in human populations so that we all carry some degree of risk. PMID:25134695

  1. Phylogeography and Demographic History of Chinese Black-Spotted Frog Populations (Pelophylax nigromaculata): Evidence for Independent Refugia Expansion and Secondary Contact

    PubMed Central

    2008-01-01

    Background Pleistocene glaciations had considerable impact on phylogeographic patterns within and among closely related species of many vertebrates. Compared to Europe and North America, research on the phylogeography of vertebrates in East Asia, particularly in China, remains limited. The black-spotted frog (Pelophylax nigromaculata) is a widespread species in East Asia. The wide distribution of this species in China makes it an ideal model for the study of palaeoclimatic effects on vertebrates in East Asia. Our previous studies of P. nigromaculata revealed significant subdivisions between the northeast China populations and populations in other regions of the mainland. In the present study, we aim to see whether the deepest splits among lineages and perhaps subsequent genealogical divisions are temporally consistent with a Pleistocene origin and whether clade geographic distributions, with insight into expansion patterns, are similarly spatially consistent with this model. Results Using 1143 nucleotides of the mitochondrial cytochrome b gene from 262 individuals sampled from 28 localities, two main clades (clade A and clade B) differing by c. 7.72% sequence divergence were defined from parsimony analyses. The corresponding timing of lineage divergence, 0.92 Mya, indicates a most likely Pleistocene split. The A clade is further subdivided into two sub-clades, A1 and A2 with 1.22% sequence divergence. Nested clade phylogeographical and population demographic analyses suggested that the current distribution of this frog species was the result of range expansion from two independent refugia during the last interglacial period. We discovered a population within which haplotype lineages A and B of P. nigromaculata coexist in the Dongliao area of China by nucleotide sequences, PCR-RFLP and ISSR (inter simple sequence repeat) patterns. The ISSR result in particular supported divergence between the mitochondrial clades A and B and implied introgressive gene flow between the two divergent lineages. Conclusion Nested clade phylogeographical and population demographic analyses indicate that the current distribution of P. nigromaculata is the result of range expansion from two independent refugia during the last interglacial period in late Pleistocene. One refugium was in east China and the lower elevations of south-western plateau. The distribution of the other mitochondrial clade is consistent with the presence of a refugium in the Korean Peninsula. The gene flow as detected by ISSR markers suggests a range expansion of the two refugia and a secondary contact between the two highly divergent lineages in the Dongliao (DL) area of northeast China. PMID:18215328

  2. Paleoeskimo Demographic History in the Canadian Arctic (ca. 4800-800 B.P.) and its Relationship to Mid-Late Holocene Climate Variability.

    NASA Astrophysics Data System (ADS)

    Savelle, J. M.

    2014-12-01

    Paleoeskimos were the first occupants of the central and eastern Canadian Arctic, spreading east from the Bering Strait region beginning approximately 4800 B.P., and occupied much of the Canadian Arctic through to their eventual disappearance ca. 800 B.P. Extensive regional archaeological site surveys throughout this area by the author and Arthur S. Dyke indicate that Paleoskimo populations underwent a series of population 'boom' (rapid expansion) and 'bust' (population declines and local extinctions) over the 4,000 year occupation history, including in the purported stable 'core area' of Foxe Basin. In this paper, we examine the contemporaneity of the local boom and bust cycles in a pan-Canadian Arctic context, and in turn examine the relationship of these cycles to mid-late Holocene climate variability.

  3. Whole-genome sequencing reveals absence of recent gene flow and separate demographic histories for Anopheles punctulatus mosquitoes in Papua New Guinea

    PubMed Central

    LOGUE, KYLE; SMALL, SCOTT T.; CHAN, ERNEST R.; REIMER, LISA; SIBA, PETER M.; ZIMMERMAN, PETER A.; SERRE, DAVID

    2015-01-01

    Anopheles mosquitoes are the vectors of several human diseases including malaria. In many malaria endemic areas, several species of Anopheles coexist, sometimes in the form of related sibling species that are morphologically indistinguishable. Determining the size and organization of Anopheles populations, and possible ongoing gene flow among them is important for malaria control and, in particular, for monitoring the spread of insecticide resistance alleles. However, these parameters have been difficult to evaluate in most Anopheles species due to the paucity of genetic data available. Here, we assess the extent of contemporary gene flow and historical variations in population size by sequencing and de novo assembling the genomes of wild-caught mosquitoes from four species of the Anopheles punctulatus group of Papua New Guinea. Our analysis of more than 50 Mb of orthologous DNA sequences revealed no evidence of contemporary gene flow among these mosquitoes. In addition, investigation of the demography of two of the An. punctulatus species revealed distinct population histories. Overall, our analyses suggest that, despite their similarities in morphology, behaviour and ecology, contemporary sympatric populations of An. punctulatus are evolving independently. PMID:25677924

  4. Whole-genome sequencing reveals absence of recent gene flow and separate demographic histories for Anopheles punctulatus mosquitoes in Papua New Guinea.

    PubMed

    Logue, Kyle; Small, Scott T; Chan, Ernest R; Reimer, Lisa; Siba, Peter M; Zimmerman, Peter A; Serre, David

    2015-03-01

    Anopheles mosquitoes are the vectors of several human diseases including malaria. In many malaria endemic areas, several species of Anopheles coexist, sometimes in the form of related sibling species that are morphologically indistinguishable. Determining the size and organization of Anopheles populations, and possible ongoing gene flow among them is important for malaria control and, in particular, for monitoring the spread of insecticide resistance alleles. However, these parameters have been difficult to evaluate in most Anopheles species due to the paucity of genetic data available. Here, we assess the extent of contemporary gene flow and historical variations in population size by sequencing and de novo assembling the genomes of wild-caught mosquitoes from four species of the Anopheles punctulatus group of Papua New Guinea. Our analysis of more than 50 Mb of orthologous DNA sequences revealed no evidence of contemporary gene flow among these mosquitoes. In addition, investigation of the demography of two of the An. punctulatus species revealed distinct population histories. Overall, our analyses suggest that, despite their similarities in morphology, behaviour and ecology, contemporary sympatric populations of An. punctulatus are evolving independently. PMID:25677924

  5. Genetic structure and demographic history of the endangered tree species Dysoxylum malabaricum (Meliaceae) in Western Ghats, India: implications for conservation in a biodiversity hotspot

    PubMed Central

    Bodare, Sofia; Tsuda, Yoshiaki; Ravikanth, Gudasalamani; Uma Shaanker, Ramanan; Lascoux, Martin

    2013-01-01

    The impact of fragmentation by human activities on genetic diversity of forest trees is an important concern in forest conservation, especially in tropical forests. Dysoxylum malabaricum (white cedar) is an economically important tree species, endemic to the Western Ghats, India, one of the world's eight most important biodiversity hotspots. As D. malabaricum is under pressure of disturbance and fragmentation together with overharvesting, conservation efforts are required in this species. In this study, range-wide genetic structure of twelve D. malabaricum populations was evaluated to assess the impact of human activities on genetic diversity and infer the species’ evolutionary history, using both nuclear and chloroplast (cp) DNA simple sequence repeats (SSR). As genetic diversity and population structure did not differ among seedling, juvenile and adult age classes, reproductive success among the old-growth trees and long distance seed dispersal by hornbills were suggested to contribute to maintain genetic diversity. The fixation index (FIS) was significantly correlated with latitude, with a higher level of inbreeding in the northern populations, possibly reflecting a more severe ecosystem disturbance in those populations. Both nuclear and cpSSRs revealed northern and southern genetic groups with some discordance of their distributions; however, they did not correlate with any of the two geographic gaps known as genetic barriers to animals. Approximate Bayesian computation-based inference from nuclear SSRs suggested that population divergence occurred before the last glacial maximum. Finally we discussed the implications of these results, in particular the presence of a clear pattern of historical genetic subdivision, on conservation policies. PMID:24223264

  6. Contrasting population genetic structure among freshwater-resident and anadromous lampreys: the role of demographic history, differential dispersal and anthropogenic barriers to movement

    PubMed Central

    Bracken, Fiona S A; Hoelzel, A Rus; Hume, John B; Lucas, Martyn C

    2015-01-01

    The tendency of many species to abandon migration remains a poorly understood aspect of evolutionary biology that may play an important role in promoting species radiation by both allopatric and sympatric mechanisms. Anadromy inherently offers an opportunity for the colonization of freshwater environments, and the shift from an anadromous to a wholly freshwater life history has occurred in many families of fishes. Freshwater-resident forms have arisen repeatedly among lampreys (within the Petromyzontidae and Mordaciidae), and there has been much debate as to whether anadromous lampreys, and their derived freshwater-resident analogues, constitute distinct species or are divergent ecotypes of polymorphic species. Samples of 543 European river lamprey Lampetra fluviatilis (mostly from anadromous populations) and freshwater European brook lamprey Lampetra planeri from across 18 sites, primarily in the British Isles, were investigated for 13 polymorphic microsatellite DNA loci, and 108 samples from six of these sites were sequenced for 829 bp of mitochondrial DNA (mtDNA). We found contrasting patterns of population structure for mtDNA and microsatellite DNA markers, such that low diversity and little structure were seen for all populations for mtDNA (consistent with a recent founder expansion event), while fine-scale structuring was evident for nuclear markers. Strong differentiation for microsatellite DNA loci was seen among freshwater-resident L. planeri populations and between L. fluviatilis and L. planeri in most cases, but little structure was evident among anadromous L. fluviatilis populations. We conclude that postglacial colonization founded multiple freshwater-resident populations with strong habitat fidelity and limited dispersal tendencies that became highly differentiated, a pattern that was likely intensified by anthropogenic barriers. PMID:25689694

  7. Coordinating rooks and bishops: an institutional history of the joint army and navy board, 1903-1919 

    E-print Network

    Godin, Jason Robert

    2005-11-01

    , the Board??s basic duties and responsibilities, and Joint Board actions as they impacted U.S. diplomacy and military strategy concerning the homeland and coast defense, the Caribbean and Cuba, the Panama Canal, as well as the Pacific and the Philippines...

  8. Coordinating rooks and bishops: an institutional history of the joint army and navy board, 1903-1919

    E-print Network

    Godin, Jason Robert

    2005-11-01

    first 6 established consultative bodies within their own services. During the presidency of Theodore Roosevelt, the Joint Board ?had the confidence of the President and enjoyed a large measure of prestige.? Yet by April 1914 and the Woodrow... has nearly an equal interest with the coast artillery,? for an offensive naval strategy required freedom provided by strong coast defense. 11 By 1905 deliberations on coast defense entered into full swing. President Theodore Roosevelt informed...

  9. Population Bulletin. Pakistan: A Demographic Report.

    ERIC Educational Resources Information Center

    Population Reference Bureau, Inc., Washington, DC.

    This report presents a brief history of Pakistan as a nation and reviews a number of demographic variables. Major topics discussed are population growth and shifts, urbanization, and labor characteristics and problems. Based on this information and projections, the report concludes with a discussion of the failure of family planning programs and…

  10. The business of demographics.

    PubMed

    Russell, C

    1984-06-01

    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

  11. Joint Effects of Habitat Heterogeneity and Species’ Life-History Traits on Population Dynamics in Spatially Structured Landscapes

    PubMed Central

    Ye, Xinping; Skidmore, Andrew K.; Wang, Tiejun

    2014-01-01

    Both habitat heterogeneity and species’ life-history traits play important roles in driving population dynamics, yet there is little scientific consensus around the combined effect of these two factors on populations in complex landscapes. Using a spatially explicit agent-based model, we explored how interactions between habitat spatial structure (defined here as the scale of spatial autocorrelation in habitat quality) and species life-history strategies (defined here by species environmental tolerance and movement capacity) affect population dynamics in spatially heterogeneous landscapes. We compared the responses of four hypothetical species with different life-history traits to four landscape scenarios differing in the scale of spatial autocorrelation in habitat quality. The results showed that the population size of all hypothetical species exhibited a substantial increase as the scale of spatial autocorrelation in habitat quality increased, yet the pattern of population increase was shaped by species’ movement capacity. The increasing scale of spatial autocorrelation in habitat quality promoted the resource share of individuals, but had little effect on the mean mortality rate of individuals. Species’ movement capacity also determined the proportion of individuals in high-quality cells as well as the proportion of individuals experiencing competition in response to increased spatial autocorrelation in habitat quality. Positive correlations between the resource share of individuals and the proportion of individuals experiencing competition indicate that large-scale spatial autocorrelation in habitat quality may mask the density-dependent effect on populations through increasing the resource share of individuals, especially for species with low mobility. These findings suggest that low-mobility species may be more sensitive to habitat spatial heterogeneity in spatially structured landscapes. In addition, localized movement in combination with spatial autocorrelation may increase the population size, despite increased density effects. PMID:25232739

  12. Emergency Care Handover (ECHO study) across care boundaries: the need for joint decision making and consideration of psychosocial history

    PubMed Central

    Sujan, Mark A; Chessum, Peter; Rudd, Michelle; Fitton, Laurence; Inada-Kim, Matthew; Spurgeon, Peter; Cooke, Matthew W

    2015-01-01

    Background Inadequate handover in emergency care is a threat to patient safety. Handover across care boundaries poses particular problems due to different professional, organisational and cultural backgrounds. While there have been many suggestions for standardisation of handover content, relatively little is known about the verbal behaviours that shape handover conversations. This paper explores both what is communicated (content) and how this is communicated (verbal behaviours) during different types of handover conversations across care boundaries in emergency care. Methods Three types of interorganisational (ambulance service to emergency department (ED) in ‘resuscitation’ and ‘majors’ areas) and interdepartmental handover conversations (referrals to acute medicine) were audio recorded in three National Health Service EDs. Handover conversations were segmented into utterances. Frequency counts for content and language forms were derived for each type of handover using Discourse Analysis. Verbal behaviours were identified using Conversation Analysis. Results 203 handover conversations were analysed. Handover conversations involving ambulance services were predominantly descriptive (60%–65% of utterances), unidirectional and focused on patient presentation (75%–80%). Referrals entailed more collaborative talk focused on the decision to admit and immediate care needs. Across all types of handover, only 1.5%–5% of handover conversation content related to the patient's social and psychological needs. Conclusions Handover may entail both descriptive talk aimed at information transfer and collaborative talk aimed at joint decision-making. Standardisation of handover needs to accommodate collaborative aspects and should incorporate communication of information relevant to the patient's social and psychological needs to establish appropriate care arrangements at the earliest opportunity. PMID:24026973

  13. 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...

  14. Youth Demographics. Fact Sheet

    ERIC Educational Resources Information Center

    Lopez, Mark Hugo; Marcelo, Karlo Barrios

    2006-01-01

    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…

  15. Asians in New York City: A Demographic Summary.

    ERIC Educational Resources Information Center

    Steingasser, Jean; And Others

    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,…

  16. Joint swelling

    MedlinePLUS

    Swelling of a joint ... Joint swelling may occur along with joint pain . The swelling may cause the joint to appear larger or abnormally shaped. Joint swelling can cause pain or stiffness. After an ...

  17. Art History Degree options

    E-print Network

    Brierley, Andrew

    66 Art History Degree options MA (Single Honours Degree) Art History MA (Joint Honours Degrees) Art knowledge of this subject? ­ No. Subject enquiries E: art.history@st-andrews.ac.uk Features * The School interest include: late mediaeval art; Italian Renaissance architecture, painting and sculpture; the history

  18. [Cancer and demographic transition].

    PubMed

    Napalkov, N P

    2004-01-01

    Two phenomena, one of which relates to the area of human reproduction and the other to the frequency, distribution, and control of disease in a population have emerged in the previous century and continue intensively to develop nowadays. Both these phenomena are directly related to the changes which are occurring in the incidence and prevalence of malignant tumours, as well as to mortality from them and to the opportunities for cancer control. The first of these phenomena has been denominated as the demographic, and the second as the epidemiological transition. The commonly accepted definition of the demographic transition is currently applied to designate a sustainable change in the type of population reproduction, when an initial and abrupt acceleration of population growth is replaced by its rapid deceleration with a subsequent stabilization of a population and a sharp change in its age structure. Demographic transition develops in a brief historical space of time and has the character of a global process. Population ageing and disequilibrium between the younger and older generations are the most important consequences of the demographic transition, and must inevitably influence the strategy and implementation of national cancer control programs. As life expectancy increases, so does the certainty that people will become more and more prone to diseases that are more common among older age groups, i.e. noncommunicable diseases and cancer in particular, rather than being affected by epidemics of infectious diseases. This situation is known as the epidemiological transition and reflects spectacular shifts in the pattern and causes of death and morbidity that have taken place in the vast majority of countries over the previous century. Epidemiological transition results in accession by poor countries to the problems of the rich, and leads to the "double burden" of disease in countries whose economies are undergoing transition, because of the still continuing burden of endemic infectious diseases. Russia is entering the final stages both of the demographic and the epidemiological transition, a period when numerous reasons, increasing demands on the systems of social protection and public health are inevitable. During the years 1992 to 2001, cancer incidence increased from 271.8 up to 313.9 per 100,000 population, i.e. a growth of over 16% and an annual rate of growth of 1.7%. According to the global estimates provided by the International Agency for Research on Cancer the number of new cancer cases in the year 2000 exceeded 10 million, and the number of deaths from cancer reached 6.2 million. The annual growth rate of global cancer incidence during the last 25-30 years was higher than the global population growth rate. Analysis of data available from population based cancer registries in Russia and abroad confirms the conclusion that cancer is mainly the fate of people belonging to the older age groups. Given the levels of exposure to specific carcinogens and genetic predisposition factors, the incidence of cancer should be considered as an exponential function of age. The unfeasibility of attempts to change, in the foreseeable future, the rate and trend of demographic transition and demographic ageing, in particular, is obvious. It would therefore be more feasible to envisage their probable consequences and to adapt the limited resources of national health and social support services to the needs of cancer control, which will significantly increase in the near future. PMID:15176213

  19. Hominin life history: reconstruction and evolution

    Microsoft Academic Search

    Shannen L. Robson; Bernard Wood

    2008-01-01

    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,

  20. An Integrated Framework for the Inference of Viral Population History From Reconstructed Genealogies

    Microsoft Academic Search

    Oliver G. Pybus; Andrew Rambaut; Paul H. Harvey

    2000-01-01

    We describe a unified set of methods for the inference of demographic history using genealogies reconstructed from gene sequence data. We introduce the skyline plot, a graphical, nonparametric estimate of demographic history. We discuss both maximum-likelihood parameter estimation and demographic hypothesis testing. Simulations are carried out to investigate the statistical properties of maximum-likeli- hood estimates of demographic parameters. The simulations

  1. Accounting for rate variation among lineages in comparative demographic analyses

    USGS Publications Warehouse

    Hope, Andrew G.; Ho, Simon Y. W.; Malaney, Jason L.; Cook, Joseph A.; Talbot, Sandra L.

    2014-01-01

    Genetic analyses of contemporary populations can be used to estimate the demographic histories of species within an ecological community. Comparison of these demographic histories can shed light on community responses to past climatic events. However, species experience different rates of molecular evolution, and this presents a major obstacle to comparative demographic analyses. We address this problem by using a Bayesian relaxed-clock method to estimate the relative evolutionary rates of 22 small mammal taxa distributed across northwestern North America. We found that estimates of the relative molecular substitution rate for each taxon were consistent across the range of sampling schemes that we compared. Using three different reference rates, we rescaled the relative rates so that they could be used to estimate absolute evolutionary timescales. Accounting for rate variation among taxa led to temporal shifts in our skyline-plot estimates of demographic history, highlighting both uniform and idiosyncratic evolutionary responses to directional climate trends for distinct ecological subsets of the small mammal community. Our approach can be used in evolutionary analyses of populations from multiple species, including comparative demographic studies.

  2. Accounting for rate variation among lineages in comparative demographic analyses.

    PubMed

    Hope, Andrew G; Ho, Simon Y W; Malaney, Jason L; Cook, Joseph A; Talbot, Sandra L

    2014-09-01

    Genetic analyses of contemporary populations can be used to estimate the demographic histories of species within an ecological community. Comparison of these demographic histories can shed light on community responses to past climatic events. However, species experience different rates of molecular evolution, and this presents a major obstacle to comparative demographic analyses. We address this problem by using a Bayesian relaxed-clock method to estimate the relative evolutionary rates of 22 small mammal taxa distributed across northwestern North America. We found that estimates of the relative molecular substitution rate for each taxon were consistent across the range of sampling schemes that we compared. Using three different reference rates, we rescaled the relative rates so that they could be used to estimate absolute evolutionary timescales. Accounting for rate variation among taxa led to temporal shifts in our skyline-plot estimates of demographic history, highlighting both uniform and idiosyncratic evolutionary responses to directional climate trends for distinct ecological subsets of the small mammal community. Our approach can be used in evolutionary analyses of populations from multiple species, including comparative demographic studies. PMID:24916007

  3. Inferring population history from genealogies 

    E-print Network

    Lohse, Konrad R.

    2010-01-01

    This thesis investigates a range of genealogical approaches to making quantitative inferences about the spatial and demographic history of populations with application to two insect systems: A local radiation of high ...

  4. Demographic variation in the Australian desert cassia under grazing pressure

    Microsoft Academic Search

    John A. Silander

    1983-01-01

    Demographic variation was examined in 3 populations of the Australian desert shrub Cassia nemophila which vary in their grazing histories. Age-specific life tables were constructed from 50 years of observations on mortality and recruitment at the Koonamore Vegetation Reserve in South Australia. Population projection matrix models were used to examine population responses to grazing pressure. The predicted population growth rates,

  5. Psychographic and Demographic Profiles of Niche Market Leisure Travelers

    Microsoft Academic Search

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

    2002-01-01

    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

  6. Spanish Americans in the United States - Changing Demographic Characteristics.

    ERIC Educational Resources Information Center

    Jaffe, A. J.; And Others

    Changes in the demographic-socioeconomic characteristics of Mexican Americans, Puerto Ricans, Cubans, Central and South Americans, and Hispanos were examined using primarily 1970 census data. The study briefly reviewed the history of these groups--when they first came to the U.S., the types of immigrants, etc.; noted their geographic distribution…

  7. Astronomy 101 Student Demographics

    NASA Astrophysics Data System (ADS)

    Deming, G. L.; Hufnagel, B.; Snyder, K. L.; Miller, E. A.

    2001-05-01

    From 1999 to 2001, the Astronomy Diagnostic Test Version 2.0 (ADT 2.0) was administered to undergraduates taking introductory astronomy for non-science majors (Astronomy 101) across the United States. A national database has been established using the results from the ADT 2.0 taken as a pretest by more than 5000 students. The 33-question multiple choice test contains 12 student background questions that can be used to create a profile of student enrollments in Astronomy 101. Students who take introductory astronomy reflect undergraduate national trends of gender, choice of major, and ethnic background. Specific questions on course expectations reveal that these students are less confident of their abilities in science than in mathematics. Mathematics background is evenly split between those who have completed only high school level topics (algebra and geometry) and those who have completed college level topics (pre-calculus and calculus). Class demographics aid in the design of effective teaching strategies for successful learning. This research was supported by the National Science Foundation through grants REC-0089239 and DGE-9714489.

  8. Population genetic evidence for complex evolutionary histories of four high altitude juniper species in the Qinghai-Tibetan Plateau.

    PubMed

    Li, Zhonghu; Zou, Jiabin; Mao, Kangshan; Lin, Kao; Li, Haipeng; Liu, Jianquan; Källman, Thomas; Lascoux, Martin

    2012-03-01

    Population genetics data based on multiple nuclear loci provide invaluable information to understand demographic, selective, and divergence histories of the current species. We studied nucleotide variation at 13 nuclear loci in 53 populations distributed among four closely related, but morphologically distinct juniper species of the Qinghai-Tibetan Plateau (QTP). We used a novel approach combining Approximate Bayesian Computation and a recently developed neutrality test based on the maximum frequency of derived mutations to examine the demographic and selective histories of individual species, and isolation-with-migration analyses to study the joint history of the species and detect gene flow between them. We found that (1) the four species, which diverged in response to the extensive QTP uplifts, have different demographic histories; (2) two loci, Pgi and CC0822, depart significantly from neutrality in one species and Pgi, is also marginally significant in another; and (3) shared polymorphisms are common, indicating both incomplete lineage sorting and gene flow after species divergence. In addition, the detected unidirectional gene flow provides indirect support for the theoretical prediction that introgression should mostly take place from local to invading species. Our results, together with previous studies, underscore complex evolutionary histories of plant diversification in the biodiversity-hotspot QTP. PMID:22380443

  9. Demographic Data in Community Assessment

    NSDL National Science Digital Library

    Shari Goldberg

    As part of a community assessment, students research demographic data for a local community. The data of the community are compared to the state and the US. This information is used to help identify needs in the community.

  10. 38 CFR 4.66 - Sacroiliac joint.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ...sharpening of the margins of the joint. Disability is manifest from...palpation and percussion over these joints, loss of normal quickness...flexion and extension of the hip. Traumatism is a rare cause...objective evidence of damage to the joint, and history of trauma...

  11. 38 CFR 4.66 - Sacroiliac joint.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...sharpening of the margins of the joint. Disability is manifest from...palpation and percussion over these joints, loss of normal quickness...flexion and extension of the hip. Traumatism is a rare cause...objective evidence of damage to the joint, and history of trauma...

  12. Art History MA (Single Honours Degree)

    E-print Network

    Brierley, Andrew

    56 Art History MA (Single Honours Degree) Art History MA (Joint Honours Degrees) Art History-specific information can be found at www.st-andrews.ac.uk/admissions/admissionsmap Subject Enquiries E: art.history-2013. Features * Art History is a popular, career-orientated subject you can take with no previous experience

  13. The demographics of macro-economic-demographic models.

    PubMed

    Bilsborrow, R E

    1989-01-01

    A number of macro-economic-demographic models have been created for developing countries during the decades of the 1970s and 1980s. Such models purport to simulate relationships between demographic variables and the process of socioeconomic development in the particular country, with the dual purposes of enhancing our knowledge of the process in particular settings and, by examining alternative scenarios, providing useful information to policy makers on the selection of demographic and economic policies to enhance economic development and improve human welfare. This paper 1st reviews the antecedents and then focuses on assessing the demographic functions (fertility, mortality, and internal migration rates) used in the 2 families of models which have had perhaps the largest number of applications in developing countries--the Bachue models, originating at the International Labour Office (Geneva), and the ESCAP models, originating at the Economic and Social Commission for Asia and the Pacific (Bangkok). Each has been applied, with significant variations, in at least 3 countries. Economic-demographic functions are defined as endogenous (and substantively meaningful, from the points of view of this paper) whenever there is an effect of economic growth or change in economic structure on the particular demographic function. The bulk of this paper assesses the realism and endogeneity of the fertility, mortality, and migration functions used in the Bachue and ESCAP models, noting, where possible, both the apparent and prima facie behavioral relationships and those that are actually important on the dynamic simulation. Shortcomings are described, including the lack of government expenditure functions with effects on demographic variables. The paper concludes more positively, noting areas of congruence and appealing endogenous relationships and functional forms specified in certain country models. It also suggests further development of, on the 1 hand, both simpler and more realistic planning models (focusing on particular behavioral relationships or sectors of importance to the country), which will be easier for country planners to understand and hence use, and, on the other hand, more complex research models aimed at enhancing our understanding of fundamental, dynamic relationships between economic factors, government policies and fertility, mortality and migration rates during the course of socioeconomic change. PMID:12342617

  14. Demographics and Productivity James Feyrer

    E-print Network

    Lotko, William

    ratio (the ratio of workers to non-workers), not on the internal demographic composition. Changes in the proportion of workers between the ages of 40 and 49 seem to be associated with productivity. Low produc- tivity levels in poor countries may be associated with workforces that are very young

  15. Are Demographics the Nation's Destiny?

    ERIC Educational Resources Information Center

    Glass, Gene V.

    2008-01-01

    In this article, the author discusses the demographic trends affecting America's public schools. As an expert on empirical evaluation of education, the author believes the major debates over vouchers, charter schools, bilingual education, and other issues are not really about preparing the next generation to compete with China or India, or about…

  16. Demographic Factors Affecting Faculty Salary

    Microsoft Academic Search

    Allen L. Webster

    1995-01-01

    This study identifies specific demographic attributes that influence salary at institutions of higher education. Data were obtained for all business faculty at nine public universities. A log-linear model with salary as the regressand serves as the functional form of estimation. Variance inflation factors are employed to reduce any aberrations that are due to the presence of multicollinearity. Additional diagnostic tests

  17. Recent developments in the tribology of artificial joints

    Microsoft Academic Search

    A. Unsworth

    1995-01-01

    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

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

    ERIC Educational Resources Information Center

    Sidener, David W.

    2006-01-01

    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…

  19. Demographics

    MedlinePLUS

    ... suffered permanent hearing loss since 2004. Musicians and Music Lovers Professional musicians, who spend their working life playing loud, amplified music are in particular danger of developing tinnitus. (Many ...

  20. Lurker demographics: counting the silent

    Microsoft Academic Search

    Blair Nonnecke; Jennifer Preece

    2000-01-01

    As online groups grow in number and type, understanding lurking is becoming increasingly important. Recent reports indicate that lurkers make up over 90% of online groups, yet little is known about them.This paper presents a demographic study of lurking in email-based discussion lists (DLs) with an emphasis on health and software-support DLs. Four primary questions are examined. One, how prevalent

  1. ORIGINAL ARTICLE Life history and demographic determinants of

    E-print Network

    Bernatchez, Louis

    as exemplified by brown trout (Salmo trutta) Dimitar Serbezov,1 Per Erik Jorde,1,2 Louis Bernatchez,3 Esben use parentage analysis of a stream-living brown trout (Salmo trutta) population to quantify the effect

  2. ORIGINAL ARTICLE Life history and demographic determinants of

    E-print Network

    Bernatchez, Louis

    as exemplified by brown trout (Salmo trutta) Dimitar Serbezov,1 Per Erik Jorde,1,2 Louis Bernatchez,3 Esben of a stream-living brown trout (Salmo trutta) population to quantify the effect of between-individual variance

  3. Arthritis at the shoulder joint.

    PubMed

    Sankaye, Prashant; Ostlere, Simon

    2015-07-01

    The shoulder is a complex joint with numerous structures contributing to mobility and stability. Shoulder pain is a common clinical complaint that may be due to a wide spectrum of disorders including rotator cuff disease, instability, and arthropathy. Primary osteoarthritis of the shoulder joint is uncommon because it is a non-weight-bearing joint. Significant osteoarthritis of the glenohumeral joint is unusual in the absence of trauma, and the detection of advanced degenerative changes in patients without a known history of trauma should alert the clinician to search for other disorders. This article reviews the pathogenesis, clinical manifestations, and key imaging findings of the common categories of the arthritis affecting the glenohumeral joint. PMID:26021591

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

    PubMed

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

    2013-09-01

    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

  5. Memory specificity and mindfulness jointly moderate the effect of reflective pondering on depressive symptoms in individuals with a history of recurrent depression.

    PubMed

    Brennan, Kate; Barnhofer, Thorsten; Crane, Catherine; Duggan, Danielle; Williams, J Mark G

    2015-05-01

    In previously depressed individuals, reflective thinking may easily get derailed and lead to detrimental effects. This study investigated the conditions in which such thinking is, or is not, adaptive. Levels of mindfulness and autobiographical memory specificity were assessed as potential moderators of the relationship between reflective thinking and depressive symptoms. Two hundred seventy-four individuals with a history of three or more previous episodes of depression completed self-report measures of depressive symptoms, rumination-including subscales for reflection and brooding-and mindfulness, as well as an autobiographical memory task to assess memory specificity. In those low in both mindfulness and memory specificity, higher levels of reflection were related to more depressive symptoms, whereas in all other groups higher levels of reflection were related to fewer depressive symptoms. The results demonstrate that the relation between reflective pondering and depressive symptoms varies depending on individual state or trait factors. In previously depressed individuals, the cognitive problem-solving aspect of reflection may be easily hampered when tendencies toward unspecific processing are increased, and awareness of mental processes such as self-judgment and reactivity is decreased. (PsycINFO Database Record PMID:25643201

  6. Memory Specificity and Mindfulness Jointly Moderate the Effect of Reflective Pondering on Depressive Symptoms in Individuals With a History of Recurrent Depression

    PubMed Central

    2015-01-01

    In previously depressed individuals, reflective thinking may easily get derailed and lead to detrimental effects. This study investigated the conditions in which such thinking is, or is not, adaptive. Levels of mindfulness and autobiographical memory specificity were assessed as potential moderators of the relationship between reflective thinking and depressive symptoms. Two hundred seventy-four individuals with a history of three or more previous episodes of depression completed self-report measures of depressive symptoms, rumination—including subscales for reflection and brooding—and mindfulness, as well as an autobiographical memory task to assess memory specificity. In those low in both mindfulness and memory specificity, higher levels of reflection were related to more depressive symptoms, whereas in all other groups higher levels of reflection were related to fewer depressive symptoms. The results demonstrate that the relation between reflective pondering and depressive symptoms varies depending on individual state or trait factors. In previously depressed individuals, the cognitive problem-solving aspect of reflection may be easily hampered when tendencies toward unspecific processing are increased, and awareness of mental processes such as self-judgment and reactivity is decreased. PMID:25643201

  7. Demographic estimation methods for plants with dormancy

    USGS Publications Warehouse

    Kery, M.; Gregg, K.B.

    2004-01-01

    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

  8. 184 History History (Hist)

    E-print Network

    Dresden, Gregory

    Civilization, 1789 to the Present Prerequisite:Freshmanorsophomorestanding. The French Revolution and Napoleon history's longest lasting monarchical system, ignited two of its largest revolutions, began World War IIandalternateyears History 107 (3)--History of the United states to 1876 The colonial period, the American Revolution

  9. Demographic Change and Parent-Child Relationships in Adulthood

    PubMed Central

    Seltzer, Judith A.; Bianchi, Suzanne M.

    2014-01-01

    Demographic changes in who becomes a parent, how many children parents have, and the marital statuses of parents and children affect the extent to which parents and adult children provide for each other later in life. We describe these demographic changes and their implications for the help parents and children give each other throughout their adult years. The changing demography of US families has increased both generations’ need for family assistance among those already disadvantaged and has exacerbated differences between the socioeconomically advantaged and disadvantaged in the availability of kin support. Variations in the marital histories of parents and children also contribute to a divergence between mother-child and father-child relationships in later life. The churning of couple relationships in both generations blurs the boundaries between who is in the family and who is not, threatening the effectiveness of the family safety net among those who may need it the most. PMID:25378767

  10. A Demographic Perspective on Family Change

    PubMed Central

    Bianchi, Suzanne M.

    2014-01-01

    Demographic analysis seeks to understand how individual microlevel decisions about child-bearing, marriage and partnering, geographic mobility, and behaviors that influence health and longevity aggregate to macrolevel population trends and differentials in fertility, mortality and migration. In this review, I first discuss theoretical perspectives—classic demographic transition theory, the perspective of the “second demographic transition,” the spread of developmental idealism—that inform demographers’ understanding of macrolevel population change. Then, I turn to a discussion of the role that demographically informed data collection has played in illuminating family change since the mid-20th century in the United States. Finally, I discuss ways in which demographic theory and data collection might inform future areas of family research, particularly in the area of intergenerational family relationships and new and emerging family forms.

  11. Posttraumatic Temporomandibular Joint Disorders

    PubMed Central

    Giannakopoulos, Helen E.; Quinn, Peter D.; Granquist, Eric; Chou, Joli C.

    2009-01-01

    The temporomandibular joint (TMJ) has many essential functions. None of its components are exempt from injury. Facial asymmetry, malocclusion, disturbances in growth, osteoarthritis, and ankylosis can manifest as complications from trauma to the TMJ. The goals of initial treatment include achievement of pretraumatic function, restoration of facial symmetry, and resolution of pain. These same objectives hold true for late repairs and reconstruction of the TMJ apparatus. Treatment is demanding, and with opposing approaches. The following article explores various treatment options for problems presenting as a result of a history of trauma to the TMJ. PMID:22110802

  12. Patellofemoral Joint Disorders

    PubMed Central

    Stalker, Robert

    1987-01-01

    Knee pain is a common presenting complaint by athletes and the general population. Disorders of the patellofemoral joint are responsible for most of these disorders. Abnormal patellar tracking is thought to be the principal cause. Patellar tracking is influenced by a number of dynamic and static factors. These can be assessed with a careful history and physical examination. A treatment program can be designed to alter the precipitating factors. Lower-extremity malalignment, principally hyperpronation of the foot, is believed to be a major cause of abnormal patellar tracking. Conservative treatment programs have had successful results, and less emphasis is now being placed on surgical procedures. PMID:21263850

  13. Using Demographic Models to Determine Intrinsic Rate of Increase and Sustainable Fishing for Elasmobranchs: Pitfalls, Advances, and Applications

    Microsoft Academic Search

    Todd Gedamke; John M. Hoenig; John A. Musick; William D. DuPaul; Samuel H. Gruber

    2007-01-01

    Leslie matrices and life tables are demographic models commonly used to evaluate the ability of specific elasmobranch life history strategies to sustain given levels and patterns of fishing pressure. These models are generally density independent and provide an instantaneous rate of population growth for a specified set of life history traits that correspond to a specific population size. Many investigators

  14. Joint Projects / Joint Seminars October 2013

    E-print Network

    Fuchs, Clemens

    Joint Projects / Joint Seminars October 2013 Information Sheet Bilateral Programs (MoU) ­ Joint Projects (JP) / Joint Seminars (JS) FWF has signed bilateral agreements ­ so called "Memorandums of Understanding" (MoU) ­ with several international partner organisations. These agreements usually aim at jointly

  15. Hysterectomy and psychiatric disorder: II. Demographic psychiatric and physical factors in relation to psychiatric outcome.

    PubMed

    Gath, D; Cooper, P; Bond, A; Edmonds, G

    1982-04-01

    One hundred and fifty-six patients with menorrhagia of benign origin were interviewed before hysterectomy, and again six months (n = 147) and 18 months (n = 148) after the operation. Psychiatric outcome, measured in terms of PSE cases detected at 18 months, was strongly associated with pre-operative mental state, neuroticism, previous psychiatric history, and family psychiatric history. No association was found with organic pathology in the uterus, bilateral oophorectomy or demographic variables. PMID:7201337

  16. A study of temporomandibular joint sounds. Part 2. Acoustic characteristics of joint sounds.

    PubMed

    Motoyoshi, M; Matsumoto, Y; Ohnuma, M; Arimoto, M; Takahashi, K; Namura, S

    1995-03-01

    In an attempt to gain a better understanding of temporomandibular joint (TMJ) sounds, we recorded joint sounds from 14 non-orthodontically treated dental students, analyzed the acoustic characteristics of the TMJ sounds, and correlated the sound characteristics with axiographic features, morphologic observations of X-ray images and clinical history. The group with a low peak frequency (< 500 Hz) of the opening click had a shorter history of subjective joint sound, a longer distance between the opening and closing curves, and a low rate of TMJ transformation. For the closing click, the history of subjective joint sounds tended to be longer when the duration of the wave was short. Acoustic analysis of TMJ sounds could be an aid to the differential diagnosis of temporomandibular disorders, although it is difficult to deduce the clinical history and internal deformities of the TMJ based solely on acoustic characteristics. PMID:7782822

  17. Demographic studies of extrasolar planets

    NASA Astrophysics Data System (ADS)

    Morton, Timothy

    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.

  18. Inferring Demographic Attributes of Anonymous Internet Users

    Microsoft Academic Search

    Dan Murray; Kevan Durrell

    2000-01-01

    Today it is quite common for web page content to include an advertisement. Since advertisers often want to target their message to people with certain demographic attributes, the anonymity of Internet users poses a special problem for them. The purpose of the present research is to find an effective way to infer demographic information (e.g. gender, age or income) about

  19. Demographic stochasticity and the variance reduction effect

    Microsoft Academic Search

    Gordon A. Fox; Bruce E. Kendall

    2002-01-01

    Demographic stochasticity is almost universally modeled as sampling var- iance in a homogeneous population, although it is defined as arising from random variation among individuals. This can lead to serious misestimation of the extinction risk in small populations. Here, we derive analytical expressions showing that the misestimation for each demographic parameter is exactly (in the case of survival) or approximately

  20. Life Potential as a Basic Demographic Indicator

    ERIC Educational Resources Information Center

    Goerlich, Francisco J.; Soler, Angel

    2013-01-01

    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

  1. Children of Divorced Parents in Demographic Perspective.

    ERIC Educational Resources Information Center

    Glick, Paul C.

    1979-01-01

    Reports on demographic changes regarding children of divorced parents between 1960-78. Shows how many children may be expected to be living with divorced parents in 1990. Also presents social and economic characteristics of divorced parents and projects demographic consequences of these patterns. (Author/GC)

  2. Influence of Insurance Status and Demographic Features on Recognition of Symptomatic and Asymptomatic Gonorrhea Cases.

    PubMed

    Flynn, Colleen; Anschuetz, Greta; Asbel, Lenore; Madera, Robbie; Johnson, Caroline C

    2015-08-01

    A random sample of individuals diagnosed as having gonorrhea from 2009 to 2013 were interviewed. Demographic and clinical features for asymptomatic and symptomatic individuals were examined to elucidate trends in medical care. Age, race, and sexually transmitted disease history had no association with the absence of symptoms (e.g., infection found by screening), whereas insurance coverage did for women. PMID:26165432

  3. The Politics of Maintaining Diversity Policies in Demographically Changing Urban-Suburban School Districts

    ERIC Educational Resources Information Center

    Diem, Sarah; Frankenberg, Erica; Cleary, Colleen; Ali, Nazneen

    2014-01-01

    This study focuses on how the demographic change occurring within two county-wide school districts and communities in the South, including the creation of suburban enclaves alongside central cities overwhelmingly made up of low-income students of color, influences community support for diversity policies within two school districts with a history

  4. Demographic analysis as an aid in shark stock assessment and management

    Microsoft Academic Search

    Enric Cortés

    1998-01-01

    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

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

    Microsoft Academic Search

    Holly A. Nance; Peter Klimley; Felipe Galván-Magańa; Jimmy Martínez-Ortíz; Peter B. Marko

    2011-01-01

    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

  6. Demographic Processes Underlying Subtle Patterns of Population Structure in the Scalloped Hammerhead

    E-print Network

    Klimley, A. Peter

    Hammerhead Shark, Sphyrna lewini Holly A. Nance1 *, Peter Klimley2 , Felipe Galva´n-Magan~ a3 , Jimmy Marti 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

  7. [Contemplations on demographic theories (author's transl)].

    PubMed

    Maier, W

    1979-03-01

    All demographic theories make statements on the relationship between population developments and economic developments. The demographic teachings of Adam Smith, Thomas Robert Malthus, and Karl Marx are embedded in their specific economic theories and contain ideologic statements which are not detrimental to demographic and economic sciences but a stimulus for research. The demographic theories which developed with the onset of the industrial revolution of the 19th century are all sceptical of too high populations independent of their analysis of the market mechanisms or of capitalistic production relationships. This has remained unchanged to date. The statistical evaluation of the 1980's underlines this problem. The reproductive behaviour and demographic theory of a highly industrialized economy can not be based on experience alone but must also be based on rational findings. The rejection of the prestige value of children on the reproductive behaviour which is independent of circumstances must be recognized. PMID:437463

  8. [The ecological limits to demographic growth].

    PubMed

    Raffestin, C

    1989-09-01

    Although most individuals are able to conceive of limitations on local resources, the idea that global resources are also potentially exhaustible appears harder to grasp. Not only are soil resources exhaustible, but the total vegetal biomass is ultimately limited by the fixed quantity of energy received from the sun. If the biomass is finite, the human population must also be finite. It would be very difficult to estimate the size of the human population that could be supported on earth because of the very different use of resources by different groups. Roughly 76% of the world's 5 billion persons live in the developing countries, and most of them weigh less heavily on the ecosystem as individuals than do persons living in the developed countries. Despite the difficulties of defining an ecologic limit on growth, the topic has held a certain fascination throughout history and various attempts have been made, most recently in 1972 with "The Limits of Growth". The question of ecological limits to growth is implicitly or explicitly posed in terms of 3 major problems: food resources, the physical capacity of ecosystems, and the territoriality of populations within ecosystems. The problem is made more complex by the fact that the objective of human societies compatible with resources. Soil erosion, inappropriate agricultural practices, pollution, the automobile and waste disposal are examples of technological aspects of society whose costs have not been rationally dealth with and which are not managed in a satisfactory manner in contemporary life. All economic and demographic growth carries with it bioecological degradation. The question of whether the earth is now overpopulated cannot be answered precisely. Nevertheless, the terrestrial ecosystem is in crisis; it is being degraded faster than it can be restored. There are no more free goods; air and water are not free. PMID:12157693

  9. Joint service EOD robotics program

    NASA Astrophysics Data System (ADS)

    Hacker, Kurt; Brezina, Byron; DeBolt, Chris

    2006-05-01

    Within the military, the Explosive Ordnance Disposal (EOD) community has been an early adopter of robotic capabilities. The Joint Service EOD (JSEOD) Program is in the process of fielding its third generation of robotic systems to the EOD technicians. Robots have been an invaluable asset to the EOD technician, and they have been critical to operations in Iraq as we prosecute the IED problem. This paper provides a brief history of past EOD robotic systems, a description of currently fielded and supported systems, and the future of robotic programs within the Joint Service EOD community.

  10. Europe and western Asia: genetics and population history

    E-print Network

    18 Europe and western Asia: genetics and population history Mark G. Thomas, Toomas Kivisild, Lounes Chikhi, and Joachim Burger This chapter examines the genetic history of Europe during the past 20 have been used extensively to address three major questions on the demographic history of Europe: (1

  11. [Demographic transition or revolution? The weaknesses and implications of the demographic transition theory. Part 1: the origins].

    PubMed

    Bourcier De Carbon, P

    1998-01-01

    The work of Adolphe Landry is reviewed in relation to development of demographic transition theory. Landry was appointed administrator in 1912 of the National Alliance Against Depopulation and remained active in it his whole life. He also helped create family allowance programs in France. As early as 1909, Landry described three different population regimes. In the "primitive" regime, which characterized all nonhuman life and human life during most of history, the population was adjusted to available subsistence by mortality. In the "intermediate" phase, restrictions on marriage and control of reproduction outside marriage maintained the population at a level below the maximum supportable. In the "contemporary" regime, the universal practice of contraception and abortion could lead to very low levels of fertility. The spread of contraception and low fertility appeared to Landry a true demographic revolution. He attributed the acceptance of contraception to a change in the common aspirations of human beings regarding their conditions, a desire for improved material well-being and social advancement, and an increased spirit of rationality and even calculation in their behavior. Landry believed that the contemporary regime, unlike the preceding two, had no mechanism implying equilibrium. The demographic revolution freed fertility from social determinants and linked it more closely to individual interests. Landry expected the contemporary regime to spread throughout the entire world, with many areas still in the primitive phase passing directly to the contemporary. He was concerned with the effects of demographic aging, and he deplored birth control propaganda that claimed it as a cure for unemployment and for overpopulation in the poor Asian countries. The birth control movements in England and the US were successful in bringing the two countries into the contemporary regime. A number of organizations such as the Population Association of America and the Office of Population Research at Princeton were favorable toward the spread of birth control through the rest of the world. PMID:12294439

  12. Inferring the Strength of Selection in Drosophila under Complex Demographic Models

    PubMed Central

    González, Josefa; Macpherson, J. Michael; Petrov, Dmitri A.

    2009-01-01

    Transposable elements (TEs) constitute a substantial fraction of the genomes of many species, and it is thus important to understand their population dynamics. The strength of natural selection against TEs is a key parameter in understanding these dynamics. In principle, the strength of selection can be inferred from the frequencies of a sample of TEs. However, complicated demographic histories, such as found in Drosophila melanogaster, could lead to a substantial distortion of the TE frequency distribution compared with that expected for a panmictic, constant-sized population. The current methodology for the estimation of selection intensity acting against TEs does not take into account demographic history and might generate erroneous estimates especially for TE families under weak selection. Here, we develop a flexible maximum likelihood methodology that explicitly accounts both for demographic history and for the ascertainment biases of identifying TEs. We apply this method to the newly generated frequency data of the BS family of non-long terminal repeat retrotransposons in D. melanogaster in concert with two recent models of the demographic history of the species to infer the intensity of selection against this family. We find the estimate to differ substantially compared with a prior estimate that was made assuming a model of constant population size. Further, we find there to be relatively little information about selection intensity present in the derived non-African frequency data and that the ancestral African subpopulation is much more informative in this respect. These findings highlight the importance of accounting for demographic history and bear on study design for the inference of selection coefficients generally. PMID:19033258

  13. Art History 95 Art History

    E-print Network

    Richards-Kortum, Rebecca

    Art History 95 Art History The School of Humanities Degrees Offered: BA, BFA The Department of Art History offers a wide range of courses in European, American,Asian, and Middle Eastern/Islamic art history with additional strengths in architectural history and film and media studies.The major in art history is struc

  14. Art History 97 Art History

    E-print Network

    Richards-Kortum, Rebecca

    Art History 97 Art History The School of Humanities Degrees Offered: BA The Department of Art History offers a wide range of courses in European, American,Asian, and Middle Eastern/Islamic art history with additional strengths in architectural history and film and media studies.The major in art history is struc

  15. Joint assembly

    NASA Technical Reports Server (NTRS)

    Wilson, Andrew (Inventor); Punnoose, Andrew (Inventor); Strausser, Katherine (Inventor); Parikh, Neil (Inventor)

    2010-01-01

    A joint assembly is provided which includes a drive assembly and a swivel mechanism. The drive assembly features a motor operatively associated with a plurality of drive shafts for driving auxiliary elements, and a plurality of swivel shafts for pivoting the drive assembly. The swivel mechanism engages the swivel shafts and has a fixable element that may be attached to a foundation. The swivel mechanism is adapted to cooperate with the swivel shafts to pivot the drive assembly with at least two degrees of freedom relative to the foundation. The joint assembly allows for all components to remain encased in a tight, compact, and sealed package, making it ideal for space, exploratory, and commercial applications.

  16. Why Women Leave Interview Protocol Demographics: Name

    E-print Network

    Sheridan, Jennifer

    Why Women Leave Interview Protocol Demographics: Name Age Length of time at UW Promoted? Title in the [NAME] department. Best things, worst things. 3. Describe your experience on campus. Best things, worst

  17. 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...

  18. Changing demographics of the American population.

    PubMed

    Halaweish, Ihab; Alam, Hasan B

    2015-02-01

    Since 1950, the United States has been in the midst of a profound demographic change: the rapid aging of the population. The baby boom generation began turning 65 in 2011 and is now driving growth at the older ages of the population. This article highlights geriatric demographic changes and illustrates how these and future trends will have wide ranging implications for the US health care system. PMID:25459538

  19. Demographic characteristics and employment among people with severe mental illness in a multisite study.

    PubMed

    Burke-Miller, Jane K; Cook, Judith A; Grey, Dennis D; Razzano, Lisa A; Blyler, Crystal R; Leff, H Stephen; Gold, Paul B; Goldberg, Richard W; Mueser, Kim T; Cook, William L; Hoppe, Sue K; Stewart, Michelle; Blankertz, Laura; Dudek, Kenn; Taylor, Amanda L; Carey, Martha Ann

    2006-04-01

    People with psychiatric disabilities experience disproportionately high rates of unemployment. As research evidence is mounting regarding effective vocational programs, interest is growing in identifying subgroup variations. Data from a multisite research and demonstration program were analyzed to identify demographic characteristics associated with employment outcomes, after adjusting for the effects of program, services, and study site. Longitudinal analyses found that people with more recent work history, younger age, and higher education were more likely to achieve competitive employment and to work more hours per month, while race and gender effects varied by employment outcome. Results provide strong evidence of demographic subgroup variation and need. PMID:16404685

  20. Naturally rare versus newly rare: demographic inferences on two timescales inform conservation of Galápagos giant tortoises

    PubMed Central

    Garrick, Ryan C; Kajdacsi, Brittney; Russello, Michael A; Benavides, Edgar; Hyseni, Chaz; Gibbs, James P; Tapia, Washington; Caccone, Adalgisa

    2015-01-01

    Long-term population history can influence the genetic effects of recent bottlenecks. Therefore, for threatened or endangered species, an understanding of the past is relevant when formulating conservation strategies. Levels of variation at neutral markers have been useful for estimating local effective population sizes (Ne) and inferring whether population sizes increased or decreased over time. Furthermore, analyses of genotypic, allelic frequency, and phylogenetic information can potentially be used to separate historical from recent demographic changes. For 15 populations of Galápagos giant tortoises (Chelonoidis sp.), we used 12 microsatellite loci and DNA sequences from the mitochondrial control region and a nuclear intron, to reconstruct demographic history on shallow (past ?100 generations, ?2500 years) and deep (pre-Holocene, >10 thousand years ago) timescales. At the deep timescale, three populations showed strong signals of growth, but with different magnitudes and timing, indicating different underlying causes. Furthermore, estimated historical Ne of populations across the archipelago showed no correlation with island age or size, underscoring the complexity of predicting demographic history a priori. At the shallow timescale, all populations carried some signature of a genetic bottleneck, and for 12 populations, point estimates of contemporary Ne were very small (i.e., < 50). On the basis of the comparison of these genetic estimates with published census size data, Ne generally represented ?0.16 of the census size. However, the variance in this ratio across populations was considerable. Overall, our data suggest that idiosyncratic and geographically localized forces shaped the demographic history of tortoise populations. Furthermore, from a conservation perspective, the separation of demographic events occurring on shallow versus deep timescales permits the identification of naturally rare versus newly rare populations; this distinction should facilitate prioritization of management action. PMID:25691990

  1. Ancient History See also Classics page 68, Classical Studies page 66,

    E-print Network

    Brierley, Andrew

    52 Ancient History See also Classics page 68, Classical Studies page 66, Greek page 102, Latin page 118, Modern Languages page 132 MA (Single Honours Degrees) Ancient History Ancient History and Archaeology History MA (Joint Honours Degrees) Ancient History and one of: Art History Biblical Studies

  2. Missed policy opportunities to advance health equity by recording demographic data in electronic health records.

    PubMed

    Douglas, Megan Daugherty; Dawes, Daniel E; Holden, Kisha B; Mack, Dominic

    2015-07-01

    The science of eliminating health disparities is complex and dependent on demographic data. The Health Information Technology for Economic and Clinical Health Act (HITECH) encourages the adoption of electronic health records and requires basic demographic data collection; however, current data generated are insufficient to address known health disparities in vulnerable populations, including individuals from diverse racial and ethnic backgrounds, with disabilities, and with diverse sexual identities. We conducted an administrative history of HITECH and identified gaps between the policy objective and required measure. We identified 20 opportunities for change and 5 changes, 2 of which required the collection of less data. Until health care demographic data collection requirements are consistent with public health requirements, the national goal of eliminating health disparities cannot be realized. PMID:25905840

  3. Temporomandibular joint involvement in ankylosing spondylitis

    PubMed Central

    Arora, Pallak; Amarnath, Janardhan; Ravindra, Setru Veerabhadrappa; Rallan, Mandeep

    2013-01-01

    Frequency of temporomandibular joint (TMJ) involvement in patients with ankylosing spondylitis (AS) has varied from 4% to 35%. It is more common in men and produces generalised stiffness in involved joints. Clinician should be suspicious of AS when a patient reports with painful restricted movements of joint, neck or back and with no trauma history. Conventional radiographic methods have allowed the demonstration of TMJ abnormalities in patients with AS, but CT is necessary to establish joint space relations and bony morphology. We describe a case of severe AS with TMJ involvement in a 40-year-old female patient and demonstrated TMJ changes on CT. A CT was able to demonstrate articular cartilage changes, disc- and joint abnormalities. Thus, if conventional radiographs in a symptomatic patient with rheumatic diseases are unable to demonstrate changes, CT can provide valuable additional information of the changes in the TMJ. PMID:23645650

  4. Humanizing History

    ERIC Educational Resources Information Center

    Blois, B. A.

    1976-01-01

    History as a social science does not need to be dull. A method which has had great success in a survey course of modern American history has been the use of oral history techniques in studying the Depression. Students responded enthusiastically and their projects formed a valuable nucleus of the school's oral history project. (Author/JDS)

  5. Identifying image preferences based on demographic attributes

    NASA Astrophysics Data System (ADS)

    Fedorovskaya, Elena A.; Lawrence, Daniel R.

    2014-02-01

    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.

  6. Joint x-ray

    MedlinePLUS

    X-ray - joint; Arthrography; Arthrogram ... x-ray technologist will help you position the joint to be x-rayed on the table. Once in place, pictures are taken. The joint may be moved into other positions for more ...

  7. Joint Aspiration (Arthrocentesis)

    MedlinePLUS

    ... the joint. It is usually due to a bacterial infection in the joint. Joint aspiration helps to diagnose ... at the time of the test. If a bacterial infection such as septic arthritis is suspected, a culture ...

  8. Joint Instability and Osteoarthritis

    PubMed Central

    Blalock, Darryl; Miller, Andrew; Tilley, Michael; Wang, Jinxi

    2015-01-01

    Joint instability creates a clinical and economic burden in the health care system. Injuries and disorders that directly damage the joint structure or lead to joint instability are highly associated with osteoarthritis (OA). Thus, understanding the physiology of joint stability and the mechanisms of joint instability-induced OA is of clinical significance. The first section of this review discusses the structure and function of major joint tissues, including periarticular muscles, which play a significant role in joint stability. Because the knee, ankle, and shoulder joints demonstrate a high incidence of ligament injury and joint instability, the second section summarizes the mechanisms of ligament injury-associated joint instability of these joints. The final section highlights the recent advances in the understanding of the mechanical and biological mechanisms of joint instability-induced OA. These advances may lead to new opportunities for clinical intervention in the prevention and early treatment of OA. PMID:25741184

  9. Effects of contraction history on control and stability in explosive actions

    Microsoft Academic Search

    G. J. C. Ettema

    2002-01-01

    In this model study, the effect of contraction history in skeletal muscle on joint movement and stability was investigated. A joint system was constructed with two identical (antagonistic) muscles. The muscles were modelled either according to the Hill tradition or as a modified Hill system including history-dependent properties. The joint system underwent movements with full activity of both muscles, mimicking

  10. Population momentum across vertebrate life histories

    USGS Publications Warehouse

    Koons, D.N.; Grand, J.B.; Arnold, J.M.

    2006-01-01

    Population abundance is critically important in conservation, management, and demographic theory. Thus, to better understand how perturbations to the life history affect long-term population size, we examined population momentum for four vertebrate classes with different life history strategies. In a series of demographic experiments we show that population momentum generally has a larger effect on long-term population size for organisms with long generation times than for organisms with short generation times. However, patterns between population momentum and generation time varied across taxonomic groups and according to the life history parameter that was changed. Our findings indicate that momentum may be an especially important aspect of population dynamics for long-lived vertebrates, and deserves greater attention in life history studies. Further, we discuss the importance of population momentum in natural resource management, pest control, and conservation arenas. ?? 2006 Elsevier B.V. All rights reserved.

  11. Demographic variation in the U.K. serotine bat: filling gaps in knowledge for management

    PubMed Central

    Chauvenet, Alienor L M; Hutson, Anthony M; Smith, Graham C; Aegerter, James N

    2014-01-01

    Species of conservation concern, or those in conflict with man, are most efficiently managed with an understanding of their population dynamics. European bats exemplify the need for successful and cost-effective management for both reasons, often simultaneously. Across Europe, bats are protected, and the concept of Favourable Conservation Status (FCS) is used as a key tool for the assessment and licensing of disruptive actions to populations. However, for efficient decision-making, this assessment requires knowledge on the demographic rates and long-term dynamics of populations. We used capture–mark–recapture to describe demographic rates for the Serotine bat (Eptesicus serotinus) at two sites in England and investigate the transition rates between three stages: juveniles, immatures, and breeders. We then use these rates in an individual-based population dynamics model to investigate the expected trajectories for both populations. Our results demonstrate for the first time the presence and scale of temporal variation in this species' demography. We describe the lengthy prereproductive period (3.5 years) that female Serotines experience. Finally, we show how site-specific variation in demographic rates can produce divergent population trajectories. Effective management of European bat populations can be achieved through the understanding of life histories, and local demographic rates and population dynamics, in order to anticipate the presence of source and sink sites in the landscape. Using the Serotine bat in England, we show that these can be obtained from rigorous and systematic studies of long-term demographic datasets. PMID:25614796

  12. Financial Bubbles and Business Scandals in History

    Microsoft Academic Search

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

    2007-01-01

    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

  13. Inferred longevity of Amazonian rainforest trees based on a long-term demographic study

    Microsoft Academic Search

    William F. Laurance; Henrique E. M. Nascimento; Susan G. Laurance; Richard Condit; Sammya D’Angelo; Ana Andrade

    2004-01-01

    We used data from a long-term (14–18 years) demographic study to infer the maximum longevity for populations of 93 relatively abundant tree species in central Amazonia. We also assessed the influence of several life-history features (wood density, growth form, mortality rate, recruitment rate, stem diameter, growth increment, population density) on tree longevity. Data on 3159 individual trees were collected in

  14. Demographic Group Differences in Adolescents' Time Attitudes

    ERIC Educational Resources Information Center

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

    2013-01-01

    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…

  15. Psychological and Demographic Correlates of Career Patterns

    ERIC Educational Resources Information Center

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

    2009-01-01

    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…

  16. DEMOGRAPHIC WHO PLAYS COMPUTER AND VIDEO GAMES?

    E-print Network

    Marketplace Netflix partnership BBC iPlayer PS3 PlayTV etc. #12;CONNECTED GAMING #12;22 | 57 NEXT GENERATIONGAMING TRENDS #12;DEMOGRAPHIC SHIFTS #12;3 | 57 WHO PLAYS COMPUTER AND VIDEO GAMES? Source: ESA "Essential Facts", 2008 65% OF AMERICAN HOUSEHOLDS PLAY COMPUTER VIDEO GAMES #12;4 | 57 COMING UP NEXT Image

  17. A Model for External Demographic Analysis.

    ERIC Educational Resources Information Center

    Hall, Barbara Ann

    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…

  18. Demographic Studies of Extrasolar Planets Timothy Morton

    E-print Network

    Winfree, Erik

    Demographic Studies of Extrasolar Planets Thesis by Timothy Morton In Partial Fulfillment 2014 (Submitted October 28, 2013) #12;ii c 2014 Timothy Morton All Rights Reserved #12;iii To V&A, my John Johnson for his willingness to take me on as a third-year student his first year at Caltech

  19. Some Demographic Correlates of Changing Newspaper Circulation.

    ERIC Educational Resources Information Center

    Eberhard, Wallace B.

    There are varied opinions on the relationship between the circulation penetration of the American daily newspapers and certain demographic indicators. Previous studies have treated the growth of circulation figures by utilizing gross national data and have indicated the role newspaper circulation plays in defining the limits of major urban…

  20. Economic and Demographic Predictors of Inclusive Education

    ERIC Educational Resources Information Center

    Cosier, Meghan E.; Causton-Theoharis, Julie

    2011-01-01

    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…

  1. Demographic Approaches to Assessing Climate Change Impact

    E-print Network

    Funk, W. Chris

    58 4 Demographic Approaches to Assessing Climate Change Impact: An Application to Pond autonomously to climate change-induced shifts as a result of extensive human modifications of these ecosystems, amphibians may be especially vulnerable to climate change impacts in both sets of landscapes, and some

  2. Count data models for demographic data

    Microsoft Academic Search

    Rainer Winkelmann; Klaus F. Zimmermann

    1994-01-01

    Key demographic variables, such as the number of children and the number of marriages or divorces, can only take integer values. This papers deals with the estimation of single equation models in which the counts are regressed on a set of observed individual characteristics such as age, gender, or nationality. Most empirical work in population economics has neglected the fact

  3. Demographic Monitoring of Wright Fishhook Cactus

    Microsoft Academic Search

    RONALD J. KASS

    Wright fishhook cactus (Sclerocactus wrightiae Benson) is a small barrel cactus endem- ic to the San Rafael Swell in south-central Utah. It was listed as an endangered species in 1979 due to its small population size, threats of over-collecting, and development associated with oil and gas. Demographic monitoring was initiated in 1993 with the following objectives: to establish permanent plots

  4. Global Demographic Trends and Social Security Reform

    Microsoft Academic Search

    Attanasio Orazio P; Gianluca Violante

    1999-01-01

    The issue of pension reform has recently received a considerable amount of attention, both in developed and in developing countries. In the former group the interest arises from the fact that current demographic trends -which project a dramatic increase in dependency ratios over the nex 20 to 40 years- make the unfunded, pay-as-you-go pension systems currently in place in most

  5. Effective hospice volunteers: Demographic and personality characteristics

    Microsoft Academic Search

    Jackie Caidwell; Jean Pearson Scott

    1994-01-01

    The purpose of the study was to examine demographic and personality characteristics of highly effective hospice volunteers. Volunteer coordinators of all Texas Hospice Organization member hospices were asked to select their most committed and effective volunteers to participate in the study. Volunteers had above-average incomes, were predominately white, female, active in other voluntary activities, and motivated by their own experiences

  6. The Demographics of Corporal Punishment in Texas

    ERIC Educational Resources Information Center

    Phillips, Stephanie

    2012-01-01

    This dissertation examined the student discipline policies of 1,025 Texas school districts, as well as data from the Texas Education Agency's Academic Excellence Indicator System in order to identify demographic patterns regarding corporal punishment policies in Texas schools. The study also studied the relationship between a district's…

  7. Urban History

    ERIC Educational Resources Information Center

    Sharpless, John B.; Warner, Sam Bass, Jr.

    1977-01-01

    Reviews the development of urban history since the 1870s and describes the present variety of urban history studies. Current studies seem to focus on either macromodels and urban systems or on internal networks and densities. (Author/AV)

  8. The joint intersection probability

    Microsoft Academic Search

    Y. H. Hatzor; A. Feintuch

    2005-01-01

    In this paper a practical method to apply block theory is presented. Block theory provides the removable joint pyramids from a given free surface regardless of the number of joints in any joint intersection. While robust, the application of the theory in real practice is hampered by the large outcome space of possibly removable joint pyramids consisting of k mutually

  9. Demographic and Clinical Characteristics of People with Intellectual Disabilities with and without Substance Abuse Disorders in a Medicaid Population

    ERIC Educational Resources Information Center

    Slayter, Elspeth Maclean

    2010-01-01

    Little is known about the demographic and clinical characteristics of people with intellectual disabilities and substance abuse problems. Drawing on health care billing claims for people with Medicaid coverage aged 12-99 years, the characteristics of people with intellectual disability and a history of substance abuse (N = 9,484) were explored and…

  10. Local adaptation under demographic and genetic fluctuations 

    E-print Network

    Banglawala, Neelofer

    2010-01-01

    Evolution frequently plays out over ecological timescales. Local adaptation under the joint action of evolutionary and ecological processes frequently leads to novel outcomes, as is evidenced by the theoretical work on ...

  11. Andres Loh joint work with Ralf Hinze

    E-print Network

    Löh, Andres

    Design goals 3 Tour of Trinity 4 Conclusions Andres L¨oh Trinity 6 #12;History of Trinity In the summerTrinity Andres L¨oh joint work with Ralf Hinze Utrecht University January 11, 2008 #12;About me Ph), polytypic / datatype-generic programming, type systems (dependent types) Andres L¨oh Trinity 2 #12;What

  12. Demographic response of cutlassfish (Trichiurus japonicus and T. nanhaiensis) to fluctuating palaeo-climate and regional oceanographic conditions in the China seas

    NASA Astrophysics Data System (ADS)

    He, Lijun; Zhang, Aibing; Weese, David; Li, Shengfa; Li, Jiansheng; Zhang, Jing

    2014-09-01

    Glacial cycles of the Quaternary have heavily influenced the demographic history of various species. To test the evolutionary impact of palaeo-geologic and climatic events on the demographic history of marine taxa from the coastal Western Pacific, we investigated the population structure and demographic history of two economically important fish (Trichiurus japonicus and T. nanhaiensis) that inhabit the continental shelves of the East China and northern South China Seas using the mitochondrial cytochrome b sequences and Bayesian Skyline Plot analyses. A molecular rate of 2.03% per million years, calibrated to the earliest flooding of the East China Sea shelf (70-140 kya), revealed a strong correlation between population sizes and primary production. Furthermore, comparison of the demographic history of T. japonicus populations from the East China and South China Seas provided evidence of the postglacial development of the Changjiang (Yangtze River) Delta. In the South China Sea, interspecific comparisons between T. japonicus and T. nanhaiensis indicated possible evolutionary responses to changes in palaeo-productivity that were influenced by East Asian winter monsoons. This study not only provides insight into the demographic history of cutlassfish but also reveals potential clues regarding the historic productivity and regional oceanographic conditions of the Western Pacific marginal seas.

  13. Modeling the evolutionary demographic processes for geomedicine

    NASA Astrophysics Data System (ADS)

    Lushnikov, A. A.; Kagan, A. I.; Gvishiani, A. D.; Lyubovtseva, Yu. S.

    2014-12-01

    We describe the principles for constructing evolutionary demographic models for geomedical statistics. Several variants of evolutionary models are proposed: (1) a model of the evolution of a closed population taking into account distribution by age, (2) a model that takes into account the morbidity and difference in mortality for groups of patients and healthy individuals, (3) a model that takes into account the distribution of different age groups by fertile ability, (4) a migration model that takes into account the population exchange between several localities, and (5) a model of the propagation of infectious diseases. Each model depends on a group of parameters determined from the medical and demographic state of the population. We discuss the possible application of the proposed evolutionary models to geomedical statistics.

  14. Simulation of Demographic Change in Palestinian Territories

    NASA Astrophysics Data System (ADS)

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

    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.

  15. The Demographic Transition: Causes and Consequences

    PubMed Central

    Galor, Oded

    2013-01-01

    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 PMID:25089157

  16. Rural Household Demographics, Livelihoods and the Environment

    PubMed Central

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

    2008-01-01

    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

  17. Stochastic game dynamics under demographic fluctuations.

    PubMed

    Huang, Weini; Hauert, Christoph; Traulsen, Arne

    2015-07-21

    Frequency-dependent selection and demographic fluctuations play important roles in evolutionary and ecological processes. Under frequency-dependent selection, the average fitness of the population may increase or decrease based on interactions between individuals within the population. This should be reflected in fluctuations of the population size even in constant environments. Here, we propose a stochastic model that naturally combines these two evolutionary ingredients by assuming frequency-dependent competition between different types in an individual-based model. In contrast to previous game theoretic models, the carrying capacity of the population, and thus the population size, is determined by pairwise competition of individuals mediated by evolutionary games and demographic stochasticity. In the limit of infinite population size, the averaged stochastic dynamics is captured by deterministic competitive Lotka-Volterra equations. In small populations, demographic stochasticity may instead lead to the extinction of the entire population. Because the population size is driven by fitness in evolutionary games, a population of cooperators is less prone to go extinct than a population of defectors, whereas in the usual systems of fixed size the population would thrive regardless of its average payoff. PMID:26150518

  18. Rural Household Demographics, Livelihoods and the Environment.

    PubMed

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

    2008-02-01

    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

  19. Climatic conditions cause complex patterns of covariation between demographic traits in a long-lived raptor.

    PubMed

    Herfindal, Ivar; van de Pol, Martijn; Nielsen, Jan T; Saether, Bernt-Erik; Mřller, Anders P

    2014-11-17

    Environmental variation can induce life-history changes that can last over a large part of the lifetime of an organism. If multiple demographic traits are affected, expected changes in climate may influence environmental covariances among traits in a complex manner. Thus, examining the consequences of environmental fluctuations requires that individual information at multiple life stages is available, which is particularly challenging in long-lived species. Here, we analyse how variation in climatic conditions occurring in the year of hatching of female goshawks Accipiter gentilis (L.) affects age-specific variation in demographic traits and lifetime reproductive success (LRS). LRS decreased with increasing temperature in April in the year of hatching, due to lower breeding frequency and shorter reproductive life span. In contrast, the probability for a female to successfully breed was higher in years with a warm April, but lower LRS of the offspring in these years generated a negative covariance among fecundity rates among generations. The mechanism by which climatic conditions generated cohort effects was likely through influencing the quality of the breeding segment of the population in a given year, as the proportion of pigeons in the diet during the breeding period was positively related to annual and LRS, and the diet of adult females that hatched in warm years contained fewer pigeons. Climatic conditions experienced during different stages of individual life histories caused complex patterns of environmental covariance among demographic traits even across generations. Such environmental covariances may either buffer or amplify impacts of climate change on population growth, emphasizing the importance of considering demographic changes during the complete life history of individuals when predicting the effect of climatic change on population dynamics of long-lived species. PMID:25403010

  20. An integrated framework for the inference of viral population history from reconstructed genealogies.

    PubMed

    Pybus, O G; Rambaut, A; Harvey, P H

    2000-07-01

    We describe a unified set of methods for the inference of demographic history using genealogies reconstructed from gene sequence data. We introduce the skyline plot, a graphical, nonparametric estimate of demographic history. We discuss both maximum-likelihood parameter estimation and demographic hypothesis testing. Simulations are carried out to investigate the statistical properties of maximum-likelihood estimates of demographic parameters. The simulations reveal that (i) the performance of exponential growth model estimates is determined by a simple function of the true parameter values and (ii) under some conditions, estimates from reconstructed trees perform as well as estimates from perfect trees. We apply our methods to HIV-1 sequence data and find strong evidence that subtypes A and B have different demographic histories. We also provide the first (albeit tentative) genetic evidence for a recent decrease in the growth rate of subtype B. PMID:10880500

  1. Independent Demographic Responses to Climate Change among Temperate and Tropical Milksnakes (Colubridae: Genus Lampropeltis).

    PubMed

    Ruane, Sara; Torres-Carvajal, Omar; Burbrink, Frank T

    2015-01-01

    The effects of Late Quaternary climate change have been examined for many temperate New World taxa, but the impact of Pleistocene glacial cycles on Neotropical taxa is less well understood, specifically with respect to changes in population demography. Here, we examine historical demographic trends for six species of milksnake with representatives in both the temperate and tropical Americas to determine if species share responses to climate change as a taxon or by area (i.e., temperate versus tropical environments). Using a multilocus dataset, we test for the demographic signature of population expansion and decline using non-genealogical summary statistics, as well as coalescent-based methods. In addition, we determine whether range sizes are correlated with effective population sizes for milksnakes. Results indicate that there are no identifiable trends with respect to demographic response based on location, and that species responded to changing climates independently, with tropical taxa showing greater instability. There is also no correlation between range size and effective population size, with the largest population size belonging to the species with the smallest geographic distribution. Our study highlights the importance of not generalizing the demographic histories of taxa by region and further illustrates that the New World tropics may not have been a stable refuge during the Pleistocene. PMID:26083467

  2. Independent Demographic Responses to Climate Change among Temperate and Tropical Milksnakes (Colubridae: Genus Lampropeltis)

    PubMed Central

    Ruane, Sara; Torres-Carvajal, Omar; Burbrink, Frank T.

    2015-01-01

    The effects of Late Quaternary climate change have been examined for many temperate New World taxa, but the impact of Pleistocene glacial cycles on Neotropical taxa is less well understood, specifically with respect to changes in population demography. Here, we examine historical demographic trends for six species of milksnake with representatives in both the temperate and tropical Americas to determine if species share responses to climate change as a taxon or by area (i.e., temperate versus tropical environments). Using a multilocus dataset, we test for the demographic signature of population expansion and decline using non-genealogical summary statistics, as well as coalescent-based methods. In addition, we determine whether range sizes are correlated with effective population sizes for milksnakes. Results indicate that there are no identifiable trends with respect to demographic response based on location, and that species responded to changing climates independently, with tropical taxa showing greater instability. There is also no correlation between range size and effective population size, with the largest population size belonging to the species with the smallest geographic distribution. Our study highlights the importance of not generalizing the demographic histories of taxa by region and further illustrates that the New World tropics may not have been a stable refuge during the Pleistocene. PMID:26083467

  3. Arch & Chord Joint Detail; Crossbracing Center Joint Detail; Chord, ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Arch & Chord Joint Detail; Crossbracing Center Joint Detail; Chord, Panel Post, Tie & Diagonal Brace Joint Detail; Chord, Panel Post, Tie & Crossbracing Joint Detail - Dunlapsville Covered Bridge, Spanning East Fork Whitewater River, Dunlapsville, Union County, IN

  4. Temporomandibular Joint Dysfunction

    MedlinePLUS

    The temporomandibular joint (TMJ) connects your jaw to the side of your head. When it works well, it enables you to ... For people with TMJ dysfunction, problems with the joint and muscles around it may cause Pain that ...

  5. Life Histories and the Strengths of Species Interactions: Combining Mortality, Growth, and Fecundity Effects

    Microsoft Academic Search

    Mark A. McPeek; Barbara L. Peckarsky

    1998-01-01

    Interactive effects of one species on another may simultaneously influence mortality, growth, and fecundity. To quantify the strength of an interaction between two species, we must therefore use techniques that integrate these various responses into es- timates of overall effect. Demographic models of populations provide such a framework. Here we develop a demographic model describing the life history of a

  6. Science history

    Microsoft Academic Search

    A J Woodall

    1967-01-01

    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

  7. Sacroiliac joint pain - aftercare

    MedlinePLUS

    The sacroiliac joint (SIJ) is a term used to describe the place where the sacrum and the iliac bones join. The ... The main purpose of the joint is to connect the spine and the pelvis. As a result, there is very little movement at the sacroiliac joint. Listed ...

  8. The Evolution of Transfers and Life Histories

    PubMed Central

    Cyrus, C. Y.

    2012-01-01

    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. PMID:22750486

  9. Simulating the Structural Response of a Preloaded Bolted Joint

    NASA Technical Reports Server (NTRS)

    Knight, Norman F., Jr.; Phillips, Dawn R.; Raju, Ivatury S.

    2008-01-01

    The present paper describes the structural analyses performed on a preloaded bolted-joint configuration. The joint modeled was comprised of two L-shaped structures connected together using a single bolt. Each L-shaped structure involved a vertical flat segment (or shell wall) welded to a horizontal segment (or flange). Parametric studies were performed using elasto-plastic, large-deformation nonlinear finite element analyses to determine the influence of several factors on the bolted-joint response. The factors considered included bolt preload, washer-surface-bearing size, edge boundary conditions, joint segment length, and loading history. Joint response is reported in terms of displacements, gap opening, and surface strains. Most of the factors studied were determined to have minimal effect on the bolted-joint response; however, the washer-bearing-surface size affected the response significantly.

  10. Demographic evidence of illegal harvesting of an endangered asian turtle.

    PubMed

    Sung, Yik-Hei; Karraker, Nancy E; Hau, Billy C H

    2013-12-01

    Harvesting pressure on Asian freshwater turtles is severe, and dramatic population declines of these turtles are being driven by unsustainable collection for food markets, pet trade, and traditional Chinese medicine. Populations of big-headed turtle (Platysternon megacephalum) have declined substantially across its distribution, particularly in China, because of overcollection. To understand the effects of chronic harvesting pressure on big-headed turtle populations, we examined the effects of illegal harvesting on the demography of populations in Hong Kong, where some populations still exist. We used mark-recapture methods to compare demographic characteristics between sites with harvesting histories and one site in a fully protected area. Sites with a history of illegal turtle harvesting were characterized by the absence of large adults and skewed ratios of juveniles to adults, which may have negative implications for the long-term viability of populations. These sites also had lower densities of adults and smaller adult body sizes than the protected site. Given that populations throughout most of the species' range are heavily harvested and individuals are increasingly difficult to find in mainland China, the illegal collection of turtles from populations in Hong Kong may increase over time. Long-term monitoring of populations is essential to track effects of illegal collection, and increased patrolling is needed to help control illegal harvesting of populations, particularly in national parks. Because few, if any, other completely protected populations remain in the region, our data on an unharvested population of big-headed turtles serve as an important reference for assessing the negative consequences of harvesting on populations of stream turtles. Evidencia Demográfica de la Captura Ilegal de una Tortuga Asiática en Peligro. PMID:23869813

  11. Genetic stratigraphy of key demographic events in Arabia.

    PubMed

    Fernandes, Verónica; Triska, Petr; Pereira, Joana B; Alshamali, Farida; Rito, Teresa; Machado, Alison; Fajkošová, Zuzana; Cavadas, Bruno; ?erný, Viktor; Soares, Pedro; Richards, Martin B; Pereira, Luísa

    2015-01-01

    At the crossroads between Africa and Eurasia, Arabia is necessarily a melting pot, its peoples enriched by successive gene flow over the generations. Estimating the timing and impact of these multiple migrations are important steps in reconstructing the key demographic events in the human history. However, current methods based on genome-wide information identify admixture events inefficiently, tending to estimate only the more recent ages, as here in the case of admixture events across the Red Sea (~8-37 generations for African input into Arabia, and 30-90 generations for "back-to-Africa" migrations). An mtDNA-based founder analysis, corroborated by detailed analysis of the whole-mtDNA genome, affords an alternative means by which to identify, date and quantify multiple migration events at greater time depths, across the full range of modern human history, albeit for the maternal line of descent only. In Arabia, this approach enables us to infer several major pulses of dispersal between the Near East and Arabia, most likely via the Gulf corridor. Although some relict lineages survive in Arabia from the time of the out-of-Africa dispersal, 60 ka, the major episodes in the peopling of the Peninsula took place from north to south in the Late Glacial and, to a lesser extent, the immediate post-glacial/Neolithic. Exchanges across the Red Sea were mainly due to the Arab slave trade and maritime dominance (from ~2.5 ka to very recent times), but had already begun by the early Holocene, fuelled by the establishment of maritime networks since ~8 ka. The main "back-to-Africa" migrations, again undetected by genome-wide dating analyses, occurred in the Late Glacial period for introductions into eastern Africa, whilst the Neolithic was more significant for migrations towards North Africa. PMID:25738654

  12. Demographic and health surveys: a profile.

    PubMed

    Corsi, Daniel J; Neuman, Melissa; Finlay, Jocelyn E; Subramanian, S V

    2012-12-01

    Demographic and Health Surveys (DHS) are comparable nationally representative household surveys that have been conducted in more than 85 countries worldwide since 1984. The DHS were initially designed to expand on demographic, fertility and family planning data collected in the World Fertility Surveys and Contraceptive Prevalence Surveys, and continue to provide an important resource for the monitoring of vital statistics and population health indicators in low- and middle-income countries. The DHS collect a wide range of objective and self-reported data with a strong focus on indicators of fertility, reproductive health, maternal and child health, mortality, nutrition and self-reported health behaviours among adults. Key advantages of the DHS include high response rates, national coverage, high quality interviewer training, standardized data collection procedures across countries and consistent content over time, allowing comparability across populations cross-sectionally and over time. Data from DHS facilitate epidemiological research focused on monitoring of prevalence, trends and inequalities. A variety of robust observational data analysis methods have been used, including cross-sectional designs, repeated cross-sectional designs, spatial and multilevel analyses, intra-household designs and cross-comparative analyses. In this profile, we present an overview of the DHS along with an introduction to the potential scope for these data in contributing to the field of micro- and macro-epidemiology. DHS datasets are available for researchers through MEASURE DHS at www.measuredhs.com. PMID:23148108

  13. Demographic Characteristics of World Class Jamaican Sprinters

    PubMed Central

    Irving, Rachael; Charlton, Vilma; Morrison, Errol; Facey, Aldeam; Buchanan, Oral

    2013-01-01

    The dominance of Jamaican sprinters in international meets remains largely unexplained. Proposed explanations include demographics and favorable physiological characteristics. The aim of this study was to analyze the demographic characteristics of world class Jamaican sprinters. Questionnaires administered to 120 members of the Jamaican national team and 125 controls elicited information on place of birth, language, ethnicity, and distance and method of travel to school. Athletes were divided into three groups based on athletic disciplines: sprint (s: 100–400?m; n = 80), jump and throw (j/t: jump and throw; n = 25) and, middle distance (md: 800–3000?m; n = 15). Frequency differences between groups were assessed using chi-square tests. Regional or county distribution of sprint differed from that of middle distance (P < 0.001) but not from that of jump and throw athletes (P = 0.24) and that of controls (P = 0.59). Sprint athletes predominately originated from the Surrey county (s = 46%, j/t = 37%, md = 17, C = 53%), whilst middle distance athletes exhibited excess from the Middlesex county (md = 60%). The language distribution of all groups showed uniformity with a predominance of English. A higher proportion of middle distance and jump and throw athletes walked to school (md = 80%, j/t = 52%, s = 10%, and C = 12%) and travelled greater distances to school. In conclusion, Jamaica's success in sprinting may be related to environmental and social factors. PMID:24396303

  14. PBS History

    NSDL National Science Digital Library

    PBS has a "neighborhood" for history, to go along with its other subject and news based areas. PBS History is basically PBS web content related to broadcast series like Frontline, The American Experience, NOVA, and POV. There are also sections devoted to independent series such as The West, (discussed in the September 20, 1996 Scout Report), Thomas Jefferson, and The Great War and the Shaping of the 20th Century, among others. PBS History is divided into geographical, biographical, and teaching aids sections. It has a section on the Presidents series, and sections on Ken Burns' Lewis and Clark documentary and an American Revolution documentary.

  15. History Extra

    NSDL National Science Digital Library

    The official website of the BBC History magazine is a great place to learn about British history via a litany of blogs, book reviews, fun quizzes, and more. It also maintains a trove of informative podcasts dating back to 2007 that will be a joy and a delight to anyone with a penchant for history. Recent conversations cover Britain in 1914, depictions of Jesus throughout the ages, and Gandhi's early years. Additionally, users can sign up to receive updates when new podcasts are added to the site.

  16. Demographic factors and playing variables in online computer gaming.

    PubMed

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

    2004-08-01

    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

  17. Family History

    MedlinePLUS

    ... Brain Aneurysm Statistics and Facts Seeking Medical Attention Pediatric Aneurysms Brain Aneurysm Causes and Risk Factors Family History Early Detection and Screening Unruptured Brain Aneurysms Subarachnoid Hemorrhage Treatment Options Aneurysm Complications Post ...

  18. OCCAM - History

    Cancer.gov

    Contact Us | Sitemap CAM at the NCI NCI CAM History Highlights of NCI CAM Activities NCI CAM Annual Report Research Funding Opportunities Grant Application Information Research Resources Funded Research Research Results Training Opportunities FAQ's

  19. Demographic aspects of functional psychoses in Canada.

    PubMed

    Bland, R C

    1977-05-01

    Canadian national data for functional psychoses (classified as schizophrenia, effective psychoses, paranoid states and reactive psychoses) are analyzed for age, sex, marital status, expectancy for first admissions and length of stay for discharges. Differences are found such that each psychosis can be distinguished from the others, thus providing indirect evidence supporting the use of the different diagnoses. The demographic characteristics of reactive psychoses from North American data have not been previously described, and are found to be similar to Scandinavian descriptions. Sex ratios for subgroup diagnoses whow similarities between catatonic schizophrenics, manic (bipolar) affectives, and reactive psychoses. Schizoaffective psychoses resemble affectives more than schizophrenia, and paraphrenia is similar to affectives. Total expectancies for functional psychosis (4.4% for males, 5.5% for females) are similar to Scandinavian figures, but the distribution by diagnosis differs, perhaps representing different diagnostic practices, but generally similar sex ratios and high rates in single persons are found. PMID:868568

  20. Mechanics of Suture Joints

    NASA Astrophysics Data System (ADS)

    Li, Yaning; Song, Juha; Ortiz, Christine; Boyce, Mary; Ortiz group/DMSE/MIT Team; Boyce group/ME/MIT Team

    2011-03-01

    Biological sutures are joints which connect two stiff skeletal or skeletal-like components. These joints possess a wavy geometry with a thin organic layer providing adhesion. Examples of biological sutures include mammalian skulls, the pelvic assembly of the armored fish Gasterosteus aculeatus (the three-spined stickleback), and the suture joints in the shell of the red-eared slider turtle. Biological sutures allow for movement and compliance, control stress concentrations, transmit loads, reduce fatigue stress and absorb energy. In this investigation, the mechanics of the role of suture geometry in providing a naturally optimized joint is explored. In particular, analytical and numerical micromechanical models of the suture joint are constructed. The anisotropic mechanical stiffness and strength are studied as a function of suture wavelength, amplitude and the material properties of the skeletal and organic components, revealing key insights into the optimized nature of these ubiquitous natural joints.

  1. ESTIMATING A ROTATION'S SELECTION PRESSURE FOR WEEDS, BASED ON JOINTED GOATGRASS DEMOGRAPHICS

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Rotations are rapidly changing in the Great Plains because of no-till systems. In place of winter wheat-fallow, producers are seeking rotations comprised of a diversity of crops. To help producers plan alternative rotations, we developed an empirical simulation model that estimated the impact of v...

  2. Demographics of a large cohort of urban chronic hepatitis C patients

    Microsoft Academic Search

    Firdous A. Siddiqui; Murray N. Ehrinpreis; James Janisse; Ravi Dhar; Elizabeth May; Milton G. Mutchnick

    2008-01-01

    Purpose  Recent studies suggest that African Americans (AA) with chronic hepatitis C (CHC) differ from non-Hispanic whites (NHW) with\\u000a respect to the natural history and mortality resulting from the complications of chronic liver disease. The aim of this study\\u000a was to examine the demographics of a large cohort of CHC patients and identify potential differences between AA and NHW.\\u000a \\u000a \\u000a \\u000a Methods  This is

  3. Digital History

    NSDL National Science Digital Library

    The Digital History website is a project of the University of Nebraska-Lincoln, designed to educate scholars and the public about the new and fast-growing academic discipline that is digital history. The home page features a semi-globe with links to the different sections atop the globe. The goal of the site is to provide access to presentations of scholars, interviews with scholars, relevant current events and news items, as well as a bibliography of digital history resources. In the "Tool Reviews" link, a visitor can read a thorough review of two tools, a timeline, and an exhibit tool from MIT's SIMILE project on open source tools. In the "Public Lectures" link, accessible from the homepage, the visitor can view portions of ten different presentations by digital history scholars, with subject matter ranging from Malcolm X to the Civil War to the Humanities and the Digital Age. Clicking on the presenter's name will lead the visitor to the portions of the presentation available for viewing, as well as a biography of the presenter, and a "live-blogged entry" about the presentation. The "Project Reviews" link, accessible on the homepage, contains reviews written by graduate students about digital history projects. Academics with projects they'd like to see reviewed, are given a contact e-mail at University of Nebraska-Lincoln.

  4. 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.

  5. 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.

  6. Handbook on dynamics of jointed structures.

    SciTech Connect

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

    2009-07-01

    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.

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

    USGS Publications Warehouse

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

    2007-01-01

    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.

  8. Two decades of Huntington disease testing: patient's demographics and reproductive choices.

    PubMed

    Krukenberg, Rebekah C; Koller, Daniel L; Weaver, David D; Dickerson, Jennifer N; Quaid, Kimberly A

    2013-10-01

    Predictive testing for Huntington disease (HD) has been available in the United States (US) since 1987, and the Indiana University Predictive Testing Program has been providing this testing since 1990. To date there has been no published description of those who present for such testing in the US. Here we describe demographics of 141 individuals and reproductive decision making of a subset of 16 of those individuals who underwent predictive HD testing between 1990 and 2010 at one site in the US. This study is a retrospective chart review of the "Personal History Questionnaire" participants completed prior to testing. As seen in other studies, most participants were female (64.5 %), in their mid-30s (mean = 34), and had at least one child prior to testing (54 %). Multiple demographic datum points are described, and the reproductive decision making of these at-risk individuals was analyzed using Fisher's Exact Tests. Of those women who had children before learning of their risk to inherit HD, those who attended church more frequently, had three or more children total, or whose mother was affected with HD were more likely to be comfortable with their choice to have children. We conclude that these demographic factors influence the reproductive decision-making of individuals at risk for HD. Psychologists, clinical geneticists, and genetic counselors may be able to use this information to help counsel at-risk patients regarding current or past reproductive decision making. PMID:23709094

  9. Aster models for life history analysis

    Microsoft Academic Search

    Charles J. Geyer; Stuart Wagenius; Ruth G. Shaw

    2007-01-01

    We present a new class of statistical models, designed for life history analysis of plants and animals, that allow joint analysis of data on survival and reproduction over multiple years, allow for variables having different probability distributions, and correctly account for the dependence of variables on earlier variables. We illustrate their utility with an analysis of data taken from an

  10. Making History

    ERIC Educational Resources Information Center

    Shein, Esther

    2008-01-01

    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…

  11. Transformations in China's population policies and demographic structure

    Microsoft Academic Search

    Dennis Tao Yang; Dandan Chen

    2004-01-01

    Abstract.?We use data from a 1992 national fertility survey to analyze China's changing demographic patterns between 1970 and 1989, covering marriage, childbearing, fertility and the gender composition of children. The analysis focuses on the relationship between population control policies and the behavior of successive marriage cohorts. Adopting a regression approach, we characterize a set of stylized demographic features in China

  12. Demographic Surprises Foreshadow Change in Neoliberal Egypt Eric Denis, CNRS

    E-print Network

    Paris-Sud XI, Université de

    Demographic Surprises Foreshadow Change in Neoliberal Egypt Eric Denis, CNRS Eric.denis@univ-paris-diderot.fr Final Draft, Middle East Report, Spring 2008, Number 246 In the Egypt of 2008, half the population has. These demographic surprises have important implications for the stability of Egypt and the regimes economic

  13. Demographic trends in the Manchester-Nashua metropolitan area

    Microsoft Academic Search

    Kenneth M. Johnson; Robert Macieski

    2009-01-01

    In the city of Manchester, New Hampshire, 25 percent of children live below the poverty line, a high rate that is in stark contrast to the state's rate of just 10 percent, one of the nation's lowest. That is the most surprising finding from this new analysis of demographic trends in the Manchester-Nashua metropolitan area. The brief presents recent demographic

  14. Growth and Demographic Change: Do Environmental Factors Matter?

    Microsoft Academic Search

    Dimitrios Varvarigos; Intan Zanariah Zakaria

    2011-01-01

    We incorporate health-damaging pollution into a three period overlapping generations model in which life expectancy, fertility and economic growth are all endogenous. We show that environmental factors can cause significant changes to the economy’s demographics. In particular, the entrepreneurial choice of less polluting production processes, induced by environmental policy, can account for such demographic changes as higher longevity and lower

  15. Examining the Impact of Demographic Factors on Air Pollution

    Microsoft Academic Search

    Matthew A. Cole; Eric Neumayer

    2004-01-01

    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.

  16. The Demographic Factors Affecting University Students' Intention to Pirate Software

    E-print Network

    Paris-Sud XI, Université de

    The Demographic Factors Affecting University Students' Intention to Pirate Software Linda Spark in South Africa to investigate the reasons why students pirate software. This paper reports on a study on the demographic factors affecting students' intention to pirate software. The study was carried out on students

  17. 1 | P a g e The Demographics of Change

    E-print Network

    Serban, Nicoleta

    . Successful companies achieve strong performance on many attributes ----- total revenue, current profitability, stock market valuation, and future potential profitability. Unsuccessful companies that experience, as the demographics of change. In this paper we elaborate the demographics of change by exploring companies' changes

  18. Campylobacter Prosthetic Joint Infection

    PubMed Central

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

    2014-01-01

    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

  19. Joint Newspaper Operating Agreements.

    ERIC Educational Resources Information Center

    Parsons, Marie

    The number of competing daily newspapers in American cities has dwindled until only about 50 cities boast two papers. Of the newspapers in those cities, 23 now maintain separate editorial operations but have joint printing, advertising, and circulation departments. The concept of joint operation is 50 years old, dating from the Depression years…

  20. Compound solder joints

    NASA Technical Reports Server (NTRS)

    Batista, R. I.; Simonson, R. B.

    1976-01-01

    Joining technique prevents contamination, may be used to join dissimilar metal tubes, minimizes fluid and gas entrapment, expedites repairs, and can yield joints having leakage rates less than 0.000001 standard cubic cm He/min. Components of joint are solder sleeve, two solder rings, Teflon sleeve, and tubing to be joined.

  1. Acromioclavicular joint disease.

    PubMed

    Mcdonald, Scott; Hopper, Melanie A

    2015-07-01

    The acromioclavicular joint is an important component of the shoulder girdle experiencing significant loading during normal activities of daily living. The joint is frequently subjected to trauma and as a synovial articulation can become involved in rheumatoid arthritis and the seronegative arthropathies. PMID:26021590

  2. Evaluating the Y chromosomal timescale in human demographic and lineage dating

    PubMed Central

    2014-01-01

    Y chromosome is a superb tool for inferring human evolution and recent demographic history from a paternal perspective. However, Y chromosomal substitution rates obtained using different modes of calibration vary considerably, and have produced disparate reconstructions of human history. Here, we discuss how substitution rate and date estimates are affected by the choice of different calibration points. We argue that most Y chromosomal substitution rates calculated to date have shortcomings, including a reliance on the ambiguous human-chimpanzee divergence time, insufficient sampling of deep-rooting pedigrees, and using inappropriate founding migrations, although the rates obtained from a single pedigree or calibrated with the peopling of the Americas seem plausible. We highlight the need for using more deep-rooting pedigrees and ancient genomes with reliable dates to improve the rate estimation. PMID:25215184

  3. ENVIRONMENTAL AND DEMOGRAPHIC CORRELATES OF BICYCLING

    PubMed Central

    Sallis, James F.; Conway, Terry L.; Dillon, Lianne I.; Frank, Lawrence D.; Adams, Marc A.; Cain, Kelli L.; Saelens, Brian E.

    2013-01-01

    OBJECTIVE The present study examined correlates of bicycle ownership, bicycling frequency, and projected increases in cycling if perceived safety from cars was improved. METHODS Participants were 1,780 adults aged 20–65 recruited from the Seattle, WA and Baltimore, MD regions (48% female; 25% ethnic/racial minority) and studied 2002–2005. Bicycling outcomes were assessed by survey. Multivariable models were conducted to examine demographic and built environment correlates of bicycling outcomes. RESULTS About 71% of the sample owned bicycles, but 60% of those did not report cycling. Among bicycle owners, frequency of riding was greater among young, male, white, educated, and lean subgroups. Neighborhood walkability measures within 1km were not consistently related to bicycling. For the whole sample, bicycling at least once per week was projected to increase from 9% to 39% if bicycling was safe from cars. Ethnic-racial minority groups and those in the least safe neighborhoods for bicycling had greater projected increases in cycling if safety from traffic was improved. CONCLUSION Implementing measures to improve bicyclists’ safety from cars would primarily benefit racial-ethnic groups who cycle less but have higher rates of chronic diseases, as well as those who currently feel least safe bicycling. PMID:23791865

  4. Emergence of Rapid Evolution from Demographic Stochasticity

    NASA Astrophysics Data System (ADS)

    Shih, Hong-Yan; Goldenfeld, Nigel

    2014-03-01

    The phenomenon of ``rapid evolution'' arises when genetic variation occurs fast enough to significantly change ecodynamics. Data from experiments with algae-rotifer system and bacteria-phage system show unusual dynamics when there are subpopulations of preys with different trait values, including predator-prey phase shifts near ? (and distinct from the canonical value of ? / 2) and so-called cryptic cycles, in which populations of preys remain constant while the predator population oscillates. Such phenomena have been modeled with deterministic differential equations containing empirical Michaelis-Menten kinetic terms and the unusual dynamics that is attributed to postulate complicated trade-off between sub-populations. Here we present a generic individual-level stochastic model of interacting populations that includes a subpopulation resistant to the predator but with metabolic cost. We solve this model by using a master equation approach, and by performing system size expansion, we find that antiphase and cryptic quasi-cycles can emerge from the combination of intrinsic demographic fluctuations and clonal mutations alone. These analytic results are then compared with Gillespie simulations, and the typical phase diagram of the system is calculated.

  5. Recent range-wide demographic expansion in a Taiwan endemic montane bird, Steere's Liocichla (Liocichla steerii)

    PubMed Central

    2010-01-01

    Background The subtropical island of Taiwan is an area of high endemism and a complex topographic environment. Phylogeographic studies indicate that vicariance caused by Taiwan's mountains has subdivided many taxa into genetic phylogroups. We used mitochondrial DNA sequences and nuclear microsatellites to test whether the evolutionary history of an endemic montane bird, Steere's Liocichla (Liocichla steerii), fit the general vicariant paradigm for a montane organism. Results We found that while mountains appear to channel gene flow they are not a significant barrier for Steere's Liocichla. Recent demographic expansion was evident, and genetic diversity was relatively high across the island, suggesting expansion from multiple areas rather than a few isolated refugia. Ecological niche modeling corroborated the molecular results and suggested that populations of Steere's Liocichla are connected by climatically suitable habitat and that there was less suitable habitat during the Last Glacial Maximum. Conclusions Genetic and ecological niche modeling data corroborate a single history--Steere's Liocichla was at lower density during the Last Glacial Maximum and has subsequently expanded in population density. We suggest that such a range-wide density expansion might be an overlooked cause for the genetic patterns of demographic expansion that are regularly reported. We find significant differences among some populations in FST indices and an admixture analysis. Though both of these results are often used to suggest conservation action, we affirm that statistically significant results are not necessarily biologically meaningful and we urge caution when interpreting highly polymorphic data such as microsatellites. PMID:20219124

  6. Demographic survey of the level and determinants of perinatal mortality in Karachi, Pakistan.

    PubMed

    Fikree, F F; Gray, R H

    1996-01-01

    A demographic survey was used to estimate the level and determinants of perinatal mortality in eight lower socio-economic squatter settlements of Karachi, Pakistan. The perinatal mortality rate was 54.1 per 1000 births, with a stillbirth to early neonatal mortality ratio of 1:1. About 65% of neonatal deaths occurred in the early neonatal period, and early neonatal mortality contributed 32% of all infant deaths. Risk factor assessment was conducted on 375 perinatal deaths and 6070 current survivors. Poorer socio-economic status variables such as maternal and paternal illiteracy, maternal work outside the home and fewer household assets were significantly associated with perinatal mortality as were biological factors of higher parental age, short birth intervals and poor obstetric history. Multivariable logistic analysis indicated that some socio-economic factors retained their significance after adjusting for the more proximate biological factors. Population attributable risk estimates suggest that public health measures for screening of high-risk women and use of family planning to space births will not improve perinatal mortality substantially without improvement of socio-economic conditions, particularly maternal education. The results of this study indicate that an evaluation of perinatal mortality can be conducted using pregnancy histories derived from demographic surveys. PMID:8746434

  7. JOINT ELECTRICAL & COMPUTER ENGINEERING AND

    E-print Network

    JOINT ELECTRICAL & COMPUTER ENGINEERING AND PHYSICS COLLOQUIUM "Speckle Statistics, Coherence confirmation of the increase in the well- defined polarization state of the output radiation. In the joint

  8. Postglacial range shift and demographic expansion of the marine intertidal snail Batillaria attramentaria.

    PubMed

    Ho, Phuong-Thao; Kwan, Ye-Seul; Kim, Boa; Won, Yong-Jin

    2015-01-01

    To address the impacts of past climate changes, particularly since the last glacial period, on the history of the distribution and demography of marine species, we investigated the evolutionary and demographic responses of the intertidal batillariid gastropod, Batillaria attramentaria, to these changes, using the snail as a model species in the northwest Pacific. We applied phylogeographic and divergence population genetic approaches to mitochondrial COI sequences from B. attramentaria. To cover much of its distributional range, 197 individuals collected throughout Korea and 507 publically available sequences (mostly from Japan) were used. Finally, a Bayesian skyline plot (BSP) method was applied to reconstruct the demographic history of this species. We found four differentiated geographic groups around Korea, confirming the presence of two distinct, geographically subdivided haplogroups on the Japanese coastlines along the bifurcated routes of the warm Tsushima and Kuroshio Currents. These two haplogroups were estimated to have begun to split approximately 400,000 years ago. Population divergence analysis supported the hypothesis that the Yellow Sea was populated by a northward range expansion of a small fraction of founders that split from a southern ancestral population since the last glacial maximum (LGM: 26,000-19,000 years ago), when the southern area became re-submerged. BSP analyses on six geographically and genetically defined groups in Korea and Japan consistently demonstrated that each group has exponentially increased approximately since the LGM. This study resolved the phylogeography of B. attramentaria as a series of events connected over space and time; while paleoceanographic conditions determining the connectivity of neighboring seas in East Asia are responsible for the vicariance of this species, the postglacial sea-level rise and warming temperatures have played a crucial role in rapid range shifts and broad demographic expansions of its populations. PMID:25691968

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

    PubMed Central

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

    2012-01-01

    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. PMID:23415755

  10. Organ History

    NSDL National Science Digital Library

    Cook, James H.

    Developed and maintained by Professor James H. Cook at Birmingham - Southern College, this site is an online tutorial that offers an interesting and interactive perspective of that king of all instruments, the organ. The site is divided into three main sections: The Organ and How it Works, Organ History, and Geographical Tour. In the first section, visitors are taken through a basic description of an organ, which then continues into a discussion of the various parts of an organ, such as the keyboards, consoles, pipes, chests, cases, and chambers. The history section begins with the invention of what is commonly understood to be the first organ, the ktseibios, built by a Greek engineer working in the third century BCE. The final section takes visitors on a chronological tour of the organ and its development throughout a number of countries, including England, France, Germany, Italy, and the United States.

  11. Smart History

    NSDL National Science Digital Library

    Under the headline "Art. History. Conversation.", Dr. Beth Harris and Dr. Steven Zucker started the Smarthistory site in 2005 as a weblog that featured free audio guides. Since that time, the site as grown into a multimedia web-book "designed as a dynamic enhancement (or even substitute) for the traditional and static art history textbook." Visitors to the site will find several hundred artworks (along with videos and podcasts) organized thematically and by time period. Additionally, visitors can also use the drop down menus on the homepage to look for certain styles, artists, and themes that include "Image and Power", "The Artist as Professional", and "Bronze Casting". The videos are a real treat, and they include offerings like "Magritte's treacherous pipe" and "Mies's corporate classicism". Finally, visitors can also learn about making a donation to their group.

  12. 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.

  13. Lisp History

    NSDL National Science Digital Library

    Paul Graham, who identifies himself as "an essayist, programmer, and programming language designer" has posted on his website a collection of articles on the history of Lisp, a programming language designed by John McCarthy in the late 1950s. The articles discuss the Roots of Lisp, What Made Lisp Different (in particular, different from Fortran) and the Evolution of Lisp, along with related articles on other aspects of Lisp's history. Other sections of his website include articles on spam filters and essays on a variety of issues written from the perspective of a programmer, including one entitled "What You'll Wish You'd Known," which he wrote for a high school talk that never happened.

  14. Uncovering History for Future History Teachers

    ERIC Educational Resources Information Center

    Fischer, Fritz

    2010-01-01

    The art of history teaching is at a crossroads. Recent scholarship focuses on the need to change the teaching of history so students can better learn history, and insists that history teachers must move beyond traditional structures and methods of teaching in order to improve their students' abilities to think with history. This article presents…

  15. River history.

    PubMed

    Vita-Finzi, Claudio

    2012-05-13

    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

  16. Harvard University's Joint Center for Housing Studies

    NSDL National Science Digital Library

    Founded in 1959, the Joint Center for Housing Studies (JCHS) at Harvard is a collaborative unit affiliated with the Graduate School of Design and the Kennedy School of Government. The Center's central focus is to "analyze the dynamic relationships between housing markets and economic, demographic, and social trends, providing leaders in government, business, and the non-profit sector with the knowledge needed to develop effective policies and strategies." The site contains links to information about ongoing research projects, educational opportunities in the field, publications, and people affiliated with JCHS. The publication section is quite strong, as visitors can browse through a diverse set of publications (many of which are available at not cost) by thematic focus, including finance, community, development, and industry studies. One of the more compelling recent publications (most of which is available here) is the monograph titled Low-Income Homeownership: Examining the Unexamined Goal.

  17. 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.

  18. WTO History Project

    NSDL National Science Digital Library

    2001-01-01

    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.

  19. Inferences of Recent and Ancient Human Population History Using Genetic and Non-Genetic Data

    ERIC Educational Resources Information Center

    Kitchen, Andrew

    2008-01-01

    I have adopted complementary approaches to inferring human demographic history utilizing human and non-human genetic data as well as cultural data. These complementary approaches form an interdisciplinary perspective that allows one to make inferences of human history at varying timescales, from the events that occurred tens of thousands of years…

  20. Unraveling male and female histories from human genetic data Jon F Wilkins

    E-print Network

    Wilkins, Jon F.

    Unraveling male and female histories from human genetic data Jon F Wilkins The increasing of human genetic diversity, and what that structure can teach us about human demographic history. Global, multi-locus analyses have suggested that human genetic diversity may fall into clusters that correspond

  1. Demographics of the European Apicultural Industry

    PubMed Central

    Chauzat, Marie-Pierre; Cauquil, Laura; Roy, Lise; Franco, Stéphanie; Hendrikx, Pascal; Ribičre-Chabert, Magali

    2013-01-01

    Over the last few years, many European and North American countries have reported a high rate of disorders (mortality, dwindling and disappearance) affecting honeybee colonies (Apis mellifera). Although beekeeping has become an increasingly professional activity in recent years, the beekeeping industry remains poorly documented in Europe. The European Union Reference Laboratory for Honeybee Health sent a detailed questionnaire to each Member State, in addition to Kosovo and Norway, to determine the demographics and state of their beekeeping industries. Based on data supplied by the National Reference Laboratory for honeybee diseases in each European country, a European database was created to describe the beekeeping industry including the number and types of beekeepers, operation size, industry production, and health (notifiable diseases, mortalities). The total number of beekeepers in Europe was estimated at 620 000. European honey production was evaluated at around 220 000 tons in 2010. The price of honey varied from 1.5 to 40 €/kg depending on the country and on the distribution network. The estimated colony winter mortality varied from 7 to 28% depending on the country and the origin of the data (institutional survey or beekeeping associations). This survey documents the high heterogeneity of the apicultural industry within the European Union. The high proportion of non-professional beekeepers and the small mean number of colonies per beekeeper were the only common characteristics at European level. The tremendous variation in European apicultural industries has implication for any comprehensive epidemiological or economic analysis of the industry. This variability needs to be taken into account for such analysis as well as for future policy development. The industry would be served if beekeeping registration was uniformly implemented across member states. Better information on the package bee and queen production would help in understanding the ability of the industry to replace lost honey bee stocks. PMID:24236084

  2. The Effect of Premorbid Demographic Factors on the Recovery of Neurocognitive Function in Traumatic Brain Injury Patients

    PubMed Central

    Jeon, Ik-Chan; Kim, Min-Su; Kim, Seong-Ho; Chang, Chul-Hoon; Bai, Dai-Seg

    2008-01-01

    Objective Premorbid demographic backgrounds of injured individuals are likely to reflect more accurately the status of patients with traumatic brian injury (TBI) than clinical factors. However, the concrete study about the relationship between the demographic factors and neurocognitive function in TBI patients has not been reported. The object of this study was to evaluate the effect of premorbid demographic factors on the recovery of neurocognitive function following TBI. Methods From July 1998 to February 2007, 293 patients (male: 228, female: 65) with a history of head injury, who had recovered from the acute phase, were selected from our hospital to include in this study. We analyzed the effect of premorbid demographic factors including age, sex, educational level and occupation on the recovery of neurocognitive function in each TBI subgroup as defined by Glasgow Coma Scale (GCS) score. Intelligence and memory are components of neurocognitive function, and the Korean Wechsler Intelligence Scale (K-WAIS) and the Korean memory assessment scale (K-MAS) were used in this study. The results were considered significant at p<0.05. Results The higher level of education was a good prognostic factor for intelligence regardless of GCS score and younger age group showed a better result for memory with an exception of severe TBI group. In the severe TBI group, the meaningful effect of demographic factors was not noted by the cause of influence of severe brain injury. Conclusion The demographic factors used in this study may be helpful for predicting the precise prognosis and developing an appropriate rehabilitation program for TBI patients. PMID:19119465

  3. Compliant Joints For Robots

    NASA Technical Reports Server (NTRS)

    Kerley, James J., Jr.

    1990-01-01

    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.

  4. 30 CFR 18.98 - Enclosures, joints, and fastenings; pressure testing.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ...or (2) A pressure rise and rate of decay consistent with unyielding components during a pressure-time history as derived from a series of oscillograms. (c) Welded joints forming an enclosure shall have continuous gastight...

  5. 30 CFR 18.98 - Enclosures, joints, and fastenings; pressure testing.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ...or (2) A pressure rise and rate of decay consistent with unyielding components during a pressure-time history as derived from a series of oscillograms. (c) Welded joints forming an enclosure shall have continuous gastight...

  6. 30 CFR 18.98 - Enclosures, joints, and fastenings; pressure testing.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ...or (2) A pressure rise and rate of decay consistent with unyielding components during a pressure-time history as derived from a series of oscillograms. (c) Welded joints forming an enclosure shall have continuous gastight...

  7. 30 CFR 18.98 - Enclosures, joints, and fastenings; pressure testing.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ...or (2) A pressure rise and rate of decay consistent with unyielding components during a pressure-time history as derived from a series of oscillograms. (c) Welded joints forming an enclosure shall have continuous gastight...

  8. [Demographic research in Togo. Evaluation of change and prospects].

    PubMed

    Nomenyo, A

    1986-01-01

    It is only since the independance of Togo, in 1958, and after 3 General Census, (1958-59, 1970, 1981), followed immediately by post-census surveys, that a solid basis of statistical data has been available for demographic research. But it is only after 1970, with the creation of the Benin University, and its Demographic Research Unit, the arrival of researchers at the ORSTOM Center of Lome, and of the demographers trained at the IFORD and IDP, that real demographic research has existed. Since then, the ORSTOM has conducted a study on the dynamics of population (fertility, migration, nuptiality, mortality) and its socioeconomic consequences on the agricultural economy of the Plateau Region (1975-1979). It is currently conducting a study in North Togo, comparing demographic data (nuptiality, fertility, infant mortality, family structure) with socioeconomic data (system of land property, women's activity, wives' status in polygamic families), for a better understanding of the influence of demographic reproduction on global social reproduction. The Demographic Research Unit led several studies on fertility in Southeast Togo and Lome. Several other surveys by the department of statistics and the IFORD, by the INRS, as well as student these from diverse schools of Benin University, are studying demo-geography, demo-economy, and demo-sociology. Still, the main problems are the bad quality of the data on fertility and mortality, and the inconsistancy of civil registration. But the interest of the present administration for demographic information may lead to the creation of a "Population Unit" assisting the government, to the definition of a status for researchers, and to the participation of Togo in the new program of Demographic and Health Surveys planned for 35 countries by the Westinghouse Institute for Resource Development. PMID:12341938

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

    PubMed Central

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

    2012-01-01

    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. PMID:22536355

  10. Panel Post & Diagonal Brace Joint Detail; Crossbracing Center Joint ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    Panel Post & Diagonal Brace Joint Detail; Crossbracing Center Joint Detail; Chord, Panel Post, Tie Bar, & Diagonal Brace Joint Detail; Chord, Tie Bar, & Crossbracing Joint Detail - Medora Bridge, Spanning East Fork of White River at State Route 235, Medora, Jackson County, IN

  11. Health & Demographic Surveillance System Profile: The Rufiji Health and Demographic Surveillance System (Rufiji HDSS).

    PubMed

    Mrema, Sigilbert; Kante, Almamy M; Levira, Francis; Mono, Amaniel; Irema, Kahema; de Savigny, Don; Masanja, Honorati

    2015-04-01

    The Rufiji Health and Demographic Surveillance System (HDSS) was established in October 1998 to evaluate the impact on burden of disease of health system reforms based on locally generated data, prioritization, resource allocation and planning for essential health interventions. The Rufiji HDSS collects detailed information on health and survival and provides a framework for population-based health research of relevance to local and national health priorities.In December 2012 the population under surveillance was about 105?503 people, residing in 19?315 households. Monitoring of households and members within households is undertaken in regular 6-month cycles known as 'rounds'. Self reported information is collected on demographic, household, socioeconomic and geographical characteristics. Verbal autopsy is conducted using standardized questionnaires, to determine probable causes of death. In conjunction with core HDSS activities, the ongoing studies in Rufiji HDSS focus on maternal and new-born health, evaluation of safety of artemether-lumefantrine (AL) exposure in early pregnancy and the clinical safety of a fixed dose of dihydroartemisinin-piperaquine (DHA-PQP) in the community. Findings of studies conducted in Rufiji HDSS can be accessed at www.ihi.or.tz/IHI-Digital-Library. PMID:25747869

  12. 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 ...

  13. DEMOGRAPHICS AND THE ECOLOGICAL ROLE OF THE CHANNEL CATFISH (ICTALURUS PUNCTATUS) IN COMMERCIALLY EXPLOITED AND

    E-print Network

    DEMOGRAPHICS AND THE ECOLOGICAL ROLE OF THE CHANNEL CATFISH (ICTALURUS PUNCTATUS) IN COMMERCIALLY;DISSERTATION APPROVAL DEMOGRAPHICS AND THE ECOLOGICAL ROLE OF THE CHANNEL CATFISH (ICTALURUS PUNCTATUS Carbondale TITLE: Demographics and the Ecological Role of the Channel Catfish (Ictalurus punctatus

  14. Volcanic Histories

    NSDL National Science Digital Library

    Robert H. Filson

    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.

  15. Geologic History

    NSDL National Science Digital Library

    Philip Medina

    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.

  16. Noninfectious joint disease in cattle.

    PubMed

    Nichols, Sylvain; Lardé, Hélčne

    2014-03-01

    Osteochondrosis causes variable degrees of joint effusion and lameness. Arthroscopic debridement of the lesions provides the best long-term outcome. Articular fracture or joint instability following collateral ligament rupture causes severe joint effusion and lameness. Internal fixation combined with external coaptation is the treatment of choice. Degenerative joint disease in young animals has a guarded prognosis. Arthroscopy combined with medical therapy may slow down the disease process. Degenerative joint disease involving the distal interphalangeal joint has a good prognosis following joint resection. PMID:24534666

  17. The second demographic transition: A concise overview of its development

    PubMed Central

    Lesthaeghe, Ron

    2014-01-01

    This article gives a concise overview of the theoretical development of the concept of the “second demographic transition” since it was coined in 1986, its components, and its applicability, first to European populations and subsequently also to non-European societies as well. Both the demographic and the societal contrasts between the first demographic transition (FDT) and the second demographic transition (SDT) are highlighted. Then, the major criticisms of the SDT theory are outlined, and these issues are discussed in the light of the most recent developments in Europe, the United States, the Far East, and Latin America. It turns out that three major SDT patterns have developed and that these evolutions are contingent on much older systems of kinship and family organization. PMID:25453112

  18. Form 4, 2013 Form 4: Faculty/Coordinator Demographic Information

    E-print Network

    Sheridan, Jennifer

    Form 4, 2013 Form 4: Faculty/Coordinator Demographic Information Grant Title: _______________________________________________________________________________________ Activity Title (if not the same as grant Pacific Islander Alaska Native Asian White Not Reported or Unknown Ethnicity: Hispanic or Latino

  19. The second demographic transition: a concise overview of its development.

    PubMed

    Lesthaeghe, Ron

    2014-12-23

    This article gives a concise overview of the theoretical development of the concept of the "second demographic transition" since it was coined in 1986, its components, and its applicability, first to European populations and subsequently also to non-European societies as well. Both the demographic and the societal contrasts between the first demographic transition (FDT) and the second demographic transition (SDT) are highlighted. Then, the major criticisms of the SDT theory are outlined, and these issues are discussed in the light of the most recent developments in Europe, the United States, the Far East, and Latin America. It turns out that three major SDT patterns have developed and that these evolutions are contingent on much older systems of kinship and family organization. PMID:25453112

  20. 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...

  1. Concise history Flucutation Relations

    E-print Network

    Concise history Flucutation Relations Discussion Nonequilibrium response, relaxation and the t Nonequilibrium response #12;Concise history Flucutation Relations Discussion Outline 1 Concise history #12;Concise history Flucutation Relations Discussion Dissipation Function In brief, we are going

  2. Gait biomechanics and the evolution of total joint replacement

    Microsoft Academic Search

    Thomas P. Andriacchi; Debra E. Hurwitz

    1997-01-01

    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

  3. Observatory conceptual development for the Joint Dark Energy Mission

    Microsoft Academic Search

    Michael J. Sholl; Gary M. Bernstein; Michael G. Dittman; Joseph M. Howard; Michael L. Lampton; John P. Lehan; J. Eric Mentzell; Robert A. Woodruff

    2009-01-01

    The Joint Dark Energy Mission (JDEM)1,2 is a proposed dark energy space mission that will measure the expansion history of the universe and the growth of its large scale structure. It is intended to provide tight constraints on the equation of state of the universe and test the validity of general relativity. Three complementary observational analyses will be employed: Baryon

  4. Robust ecological pattern formation induced by demographic noise

    Microsoft Academic Search

    Thomas Butler; Nigel Goldenfeld

    2009-01-01

    We demonstrate that demographic noise can induce persistent spatial pattern formation and temporal oscillations in the Levin-Segel predator-prey model for plankton-herbivore population dynamics. Although the model exhibits a Turing instability in mean-field theory, demographic noise greatly enlarges the region of parameter space where pattern formation occurs. To distinguish between patterns generated by fluctuations and those present at the mean-field level

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

    PubMed Central

    Rao, Dingqi; Yang, Junxing

    2012-01-01

    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

  6. How do SNP ascertainment schemes and population demographics affect inferences about population history?

    E-print Network

    McTavish, Emily Jane Bell; Hills, David M

    2015-03-17

    and westslope cutthroat trout. Mol Ecol Resour. 2011;11:117–22. 15. Schwenke PL, Rhydderch JG, Ford MJ, Marshall AR, Park LK. Forensic identification of endangered Chinook Salmon (Oncorhynchus tshawytscha) using a multilocus SNP assay. Conserv Genet. 2006...

  7. Phylogeographic structure, demographic history and morph composition in a colour polymorphic lizard.

    PubMed

    McLean, C A; Stuart-Fox, D; Moussalli, A

    2014-10-01

    In polymorphic species, population divergence in morph composition and frequency has the potential to promote speciation. We assessed the relationship between geographic variation in male throat colour polymorphism and phylogeographic structure in the tawny dragon lizard, Ctenophorus decresii. We identified four genetically distinct lineages, corresponding to two polymorphic lineages in the Northern Flinders Ranges and Southern Flinders Ranges/Olary Ranges regions respectively, and a monomorphic lineage in the Mt Lofty Ranges/Kangaroo Island region. The degree of divergence between these three lineages was consistent with isolation to multiple refugia during Pleistocene glacial cycles, whereas a fourth, deeply divergent (at the interspecific level) and monomorphic lineage was restricted to western New South Wales. The same four morphs occurred in both polymorphic lineages, although populations exhibited considerable variation in the frequency of morphs. By contrast, male throat coloration in the monomorphic lineages differed from each other and from the polymorphic lineages. Our results suggest that colour polymorphism has evolved once in the C. decresii species complex, with subsequent loss of polymorphism in the Mt Lofty Ranges/Kangaroo Island lineage. However, an equally parsimonious scenario, that polymorphism arose independently twice within C. decresii, could not be ruled out. We also detected evidence of a narrow contact zone with limited genotypic admixture between the polymorphic Olary Ranges and monomorphic Mt Lofty Ranges regions, yet no individuals of intermediate colour phenotype. Such genetic divergence and evidence for barriers to gene flow between lineages suggest incipient speciation between populations that differ in morph composition. PMID:25146412

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

    PubMed

    2014-08-01

    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

  9. Speciation and demographic history of Atlantic eels (Anguilla anguilla and A. rostrata) revealed by mitogenome sequencing.

    PubMed

    Jacobsen, M W; Pujolar, J M; Gilbert, M T P; Moreno-Mayar, J V; Bernatchez, L; Als, T D; Lobon-Cervia, J; Hansen, M M

    2014-11-01

    Processes leading to speciation in oceanic environments without obvious physical barriers remain poorly known. European and American eel (Anguilla anguilla and A. rostrata) spawn in partial sympatry in the Sargasso Sea. Larvae are advected by the Gulf Stream and other currents towards the European/North African and North American coasts, respectively. We analyzed 104 mitogenomes from the two species along with mitogenomes of other Anguilla and outgroup species. We estimated divergence time between the two species to identify major events involved in speciation. We also considered two previously stated hypotheses: one where the ancestral species was present in only one continent but was advected across the Atlantic by ocean current changes and another where population declines during Pleistocene glaciations led to increasing vicariance, facilitating speciation. Divergence time was estimated to ?3.38 Mya, coinciding with the closure of the Panama Gateway that led to reinforcement of the Gulf Stream. This could have advected larvae towards European/North African coasts, in which case American eel would be expected to be the ancestral species. This scenario could, however, not be unequivocally confirmed by analyses of dN/dS, nucleotide diversity and effective population size estimates. Extended bayesian skyline plots showed fluctuations of effective population sizes and declines during glaciations, and thus also lending support to the importance of vicariance during speciation. There was evidence for positive selection at the ATP6 and possibly ND5 genes, indicating a role in speciation. The findings suggest an important role of ocean current changes in speciation of marine organisms. PMID:24865601

  10. Demographic history and population structure of the Antarctic silverfish Pleuragramma antarcticum.

    PubMed

    Zane, L; Marcato, S; Bargelloni, L; Bortolotto, E; Papetti, C; Simonato, M; Varotto, V; Patarnello, T

    2006-12-01

    The Antarctic silverfish Pleuragramma antarcticum (Nototheniidae) is the most abundant pelagic fish inhabiting Antarctic waters. In this study we investigated, through partial sequencing of the D-loop mitochondrial region, samples collected at four different locations in the Southern Ocean, three in the Atlantic and one in the Pacific sector. Sampling was replicated in two different years at two locations. Sequence analysis showed a remarkably high polymorphism, with 110 haplotypes over the 256 investigated specimens, and about 80% of haplotypes occurring only once. Neutrality tests indicated that all samples were not at mutation-drift equilibrium, and suggested a past population expansion. This result was supported by the presence of a star-like topology in the D-loop gene tree, and by results of mismatch distribution. The start of the expansion was dated, using a specifically calibrated clock, between 111 and 126 thousand years ago. This value corresponds to the start of the cooling period that led to the last glaciation peak, and is in close agreement with a recently suggested range expansion for pelagic Antarctic ecosystems. Analysis of molecular variation indicated a small, though highly significant, value of differentiation between samples. This result, together with the lack of association between clades and geographical locations, indicates a weak population structure for the species. PMID:17107479

  11. Implications of ecological energetics and biophysical and developmental constraints for life history variation in dinosaurs

    SciTech Connect

    Dunham, A.E.; Overall, K.L.; Forster, C.A.; Porter, W.P.

    1988-01-01

    There has been much recent speculation concerning the nature of life history variation in dinosaurs (Case, 1978; Bakker, 1986; Horner, 1982, 1984a). The purpose of this paper is to review the data on dinosaur life histories and to examine the nature and magnitude of the demographic and physiological factors that must have constrained life history variation in this group. 145 refs., 8 figs., 3 tabs.

  12. 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.

  13. Moving History

    NSDL National Science Digital Library

    While it took many decades for some skeptics to realize the importance of maintaining archives devoted to preserving film and television programs, the movement has certainly gained a critical mass of interested organizations in recent years. One particularly nice online resource for such matters is the Moving History website, which serves as a research guide to the United Kingdomâ??s twelve public sector film archives. With support from Britainâ??s Arts and Humanities Research Council, the site includes sections that describe each of the collections, along with a lovely selection of 100 film clips. The clips can be browsed by theme and host archive, and they include depictions of British â??holiday-makingâ?ť trips and segments from the popular British television series, â??Steptoe and Sonâ?ť. The site is rounded out by the inclusion of a set of links to related organizations, such as the Association of Moving Image Archivists and the British PathĂ© Film Archive.

  14. The Joint Confidence Level Paradox: A History of Denial

    NASA Technical Reports Server (NTRS)

    Butts, Glenn; Linton, Kent

    2009-01-01

    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.

  15. Sino-American Joint Partnerships: Why Some Succeed and Others Fail. Research & Occasional Paper Series: CSHE.1.14

    ERIC Educational Resources Information Center

    Julius, Daniel J.; Leventhal, Mitch

    2014-01-01

    This article examines institutional and demographic variables associated with successful joint partnerships between US and Chinese institutions of higher education. Understanding those variables requires an appreciation of overarching issues or catalysts bringing both nations together and, as well, how postsecondary environments differ and the…

  16. ISHKS joint registry: A preliminary report

    PubMed Central

    Pachore, Jawahir A; Vaidya, Shrinand V; Thakkar, Chandrasekhar J; Bhalodia, Haresh Kumar P; Wakankar, Hemant M

    2013-01-01

    Background: Total knee arthroplasty (TKA) and total hip arthroplasty (THA) are the most widely practiced surgical options for arthritis all over the world and its application is rising in India. Indian Society of Hip and Knee Surgeons (ISHKS) has established a joints registry and has been collecting data for last 6 years. Materials & Methods: All members of ISHKS are encouraged to actively participate in the registry. A simple two page knee and hip form can be downloaded from the website www.ishks.com. The information collected includes patient demographics, indication for surgery, implant details and in case of revision arthroplasty: the details of implants removed and the cause of failure of primary arthroplasty. These forms are mailed to the central registry office and the data is fed in computerized registry. Data collection started in October 2006. Results: Joint registry is a very important initiative of ISHKS and till date, have data of 34,478 TKAs and 3604 THAs, contributed by 42 surgeons across India. Some important observations have emerged. Data of 34,478 TKAs was assessed: These included 8612 males (25%) and 25,866 females (75%). Average age was 64.4 years (Osteoarthritis range: 45 to 88 years; Rheumatoid arthritis range: 22 to 74 years). Average body mass index was 29.1 (Range: 18.1 to 42.9). The indication for TKA was osteoarthritis in 33,444 (97%) and rheumatoid arthritis in 759 (2.2%). Total of 3604 THA procedures were recorded. These included 2162 (60%) male patients and 1442 (40%) female patients. Average age was 52 years (Range 17 to 85 years) and average BMI was 25.8 (Range: 17.3 to 38.5). The indications for THA was AVN in 49%. Conclusion: The registry will become more meaningful in years to come. Active participation of all arthroplasty surgeons across India is vital for the success of the joints registry. PMID:24133312

  17. New Joint Sealants. Criteria, Design and Materials.

    ERIC Educational Resources Information Center

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

    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…

  18. An Exploratory Examination of the Association Between Altered Lumbar Motor Control, Joint Mobility and Low Back Pain in Athletes

    PubMed Central

    Corkery, Marie B.; O’Rourke, Brittany; Viola, Samantha; Yen, Sheng-Che; Rigby, Joseph; Singer, Kevin; Thomas, Adam

    2014-01-01

    Background: Low back pain (LBP) is a common cause of lost playing time and can be a challenging clinical condition in competitive athletes. LBP in athletes may be associated with joint and ligamentous hypermobility and impairments in activation and coordination of the trunk musculature, however there is limited research in this area. Objectives: To determine if there is an association between altered lumbar motor control, joint mobility and low back pain (LBP) in a sample of athletes. Materials and Methods: Fifteen athletes with LBP were matched by age, gender and body mass index (BMI) with controls without LBP. Athletes completed a questionnaire with questions pertaining to demographics, activity level, medical history, need to self-manipulate their spine, pain intensity and location. Flexibility and lumbar motor control were assessed using: active and passive straight leg raise, lumbar range of motion (ROM), hip internal rotation ROM (HIR), Beighton ligamentous laxity scale, prone instability test (PIT), observation of lumbar aberrant movements, double leg lowering and Trendelenburg tests. Descriptive statistics were compiled and the chi square test was used to analyze results. Results: Descriptive statistics showed that 40% of athletes with LBP exhibited aberrant movements (AM), compared to 6% without LBP. 66% of athletes with LBP reported frequently self-manipulating their spine compared to 40% without LBP. No significant differences in motor control tests were found between groups. Athletes with LBP tended to have less lumbar flexion (63 ± 11°) compared to those without LBP (66 ± 13°). Chi-Square tests revealed that the AM were more likely to be present in athletes with LBP than those without (X2 = 4.66, P = 0.03). Conclusions: The presence of aberrant movement patterns is a significant clinical finding and associated with LBP in athletes. PMID:25741418

  19. Joint for deployable structures

    NASA Technical Reports Server (NTRS)

    Craighead, N. D., II; Preliasco, R. J.; Hult, T. D. (inventors)

    1985-01-01

    A joint is described for connecting a pair of beams to pivot them between positions in alignment or beside one another, which is of light weight and which operates in a controlled manner. The joint includes a pair of fittings and at least one center link having opposite ends pivotally connected to opposite fittings and having axes that pass through centerplates of the fittings. A control link having opposite ends pivotally connected to the different fittings controls their relative orientations, and a toggle assemly holds the fittings in the deployed configuration wherein they are aligned. The fittings have stops that lie on one side of the centerplane opposite the toggle assembly.

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

    NASA Astrophysics Data System (ADS)

    Soliani, Lamberto; Rossi, Orazio

    1992-09-01

    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.

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

    USGS Publications Warehouse

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

    2012-01-01

    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.

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

    PubMed Central

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

    2013-01-01

    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. PMID:24141961

  3. Contraceptive discontinuation and switching among Ghanaian women: evidence from the Ghana Demographic and Health Survey, 2008.

    PubMed

    Modey, Emefa J; Aryeetey, Richmond; Adanu, Richard

    2014-03-01

    This study identifies factors associated with contraceptive discontinuation and switching among Ghanaian women of reproductive age, using data from 1,378 female respondents of the 2008 Ghana Demographic and Health Survey. Logistic regression models were used to determine relationships between key socio-demographic factors and user status. Discontinued use occurred among 56% of ever users and switching among 55% of current users. The IUD was most abandoned (70%) and its use was associated with almost twice the odds of discontinuation (OR = 1.97; 95% CI (1.04, 3.75)). Having a history of terminated pregnancy significantly predicted both discontinuation (OR = 1.36; 95% CI (1.03, 1.79) and switching (OR = 1.78; 95% CI (1.16, 2.73)) and intention to limit births significantly predicted lower discontinuation (OR = 0.71; 95% CI (0.52, 0.96)). Counseling services emphasizing contraceptive options and reinforcing switching are critically needed to reduce unwanted pregnancies that may result from poor method use and discontinuation especially among post-abortion clients and IUD users. PMID:24796172

  4. Joints in a Cornstarch Analog

    NSDL National Science Digital Library

    Juliet Crider

    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.

  5. Endogenous technological and demographic change under increasing water scarcity

    NASA Astrophysics Data System (ADS)

    Pande, Saket; Ertsen, Maurits; Sivapalan, Murugesu

    2014-05-01

    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.

  6. Child Pornography Possessors and Child Contact Sex Offenders: A Multilevel Comparison of Demographic Characteristics and Rates of Recidivism.

    PubMed

    Faust, Erik; Bickart, William; Renaud, Cheryl; Camp, Scott

    2014-02-19

    Considerable debate surrounds the topic of whether possessing or distributing online images of child pornography (CP) represents a new type of crime perpetrated by conventional sex offenders (e.g., child contact [CC] sex offenders), or whether individuals who commit these crimes differ from contact sex offenders in meaningful ways. The current study compares groups of Internet (CP) and CC sexual offenders, with each group's sexual offending history exclusively confined to its offense category. T tests were used to conduct bivariate comparisons of group demographics and criminal histories. Rates of recidivism were examined using survival curves and Cox proportional hazard regression models. Results showed significant differences on demographic and criminal history variables, with CP offenders demonstrating a lower frequency of prior criminal offending and substance abuse, and higher rates of pre-incarceration employment and level of education. Rates of recidivism were significantly different between the two groups, with CP offenders showing lower rates of re-offense for most measures of recidivism. When controlling for background characteristics and the timing of the event, CC offenders were at much greater risk for having an arrest for a new crime or a non-sexual violent crime than CP offenders. Treatment and policy implications are discussed, along with suggestions for future research. PMID:24556314

  7. Nonfamily child abductors who murder their victims: offender demographics from interviews with incarcerated offenders.

    PubMed

    Beyer, Kristen R; Beasley, James O

    2003-10-01

    Nonfamily child abductions have a low rate of occurrence despite the media attention and public hysteria that these types of cases often attract. Although the annual incident rate is low, nonfamily child abductions are emotionally charged crimes that can rapidly overwhelm law enforcement resources. The 24-hour period following an abduction is critical, and law enforcement must be prepared to respond immediately and effectively. The purpose of the present research is to obtain demographic and background history on convicted nonfamily child abductors who have murdered their victims. Data for the study were obtained through interviews of incarcerated offenders and review of case documents. To date, interviews with 25 child abductors who murdered their victims have been conducted within various prison facilities. PMID:19771715

  8. Clad metal joint closure

    SciTech Connect

    Siebert, O.W.

    1985-04-09

    A plasma arc spray overlay of cladding metals is used over joints between clad metal pieces to provide a continuous cladding metal surface. The technique permits applying an overlay of a high melting point cladding metal to a cladding metal surface without excessive heating of the backing metal.

  9. CARTILAGE, BONES, AND JOINTS

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Cartilage is a special type of connective tissue that is of extreme importance in embryonic development, serving as the model upon which true bone is later formed. Cartilage also persists in adult animals, primarily as articular cartilage which cushions the interface between adjacent bones or joint...

  10. Joint publication: Department of

    E-print Network

    Watson, Craig A.

    century. The first law to protect consumers was passed in 1906, and Charles Dadant is credited with getJoint publication: Florida Department of Agriculture & Consumer Services University of Florida Florida Department of Agriculture & Consumer Services 1911 SW 34 Street PO Box 147100 Gainesville, FL

  11. Dolphin Skeleton (Gliding Joint)

    NSDL National Science Digital Library

    Ketan Patel (California State University, Fullerton; )

    2007-07-14

    The dolphin is built to be sleek. Its body is made of almost entirely backbone (a gliding joint) which makes it very flexible under water. The ribs protect the inner organs of the dolphin and the tail beats from side to side, thrusting the animal forward.

  12. Joint Honours AFRICAN STUDIES

    E-print Network

    Miall, Chris

    : The Joint Honours African Studies degree programme at Birmingham is broad, combining arts and social Office - Retail management - Aid work with Save the Children - Probation work - Welfare rights worker - Computer programmer - NGO work in Kurdistan - Work with adults who have learning disabilities - Research

  13. Gauge accreditation facility - history and future recommendations

    SciTech Connect

    Vik, S.A.; Botto, G.; Kviljo, K. [SPE, Richardson, TX (United States)] [and others

    1995-12-31

    This paper presents the history of the {open_quote}Gauge Accreditation Facility{close_quote} project. Twelve large oil companies sponsored a joint industry project to test and compare a large number of memory and permanent pressure gauges. The project experienced a significant improvement in gauge quality and services during and after the project. This paper will present information about the project focusing on memory gauges as these were the bulk of the gauges tested.

  14. Joint Institute Marine and Atmospheric

    E-print Network

    Hawai'i at Manoa, University of

    Joint Institute for Marine and Atmospheric Research NATIONALOCEA NIC AND ATMOSPHERIC ADMINISTRATION Contribution 00-328 #12;ii This research is funded by Cooperative Agreement Number NA67RJ0154 between the Joint

  15. Health & Demographic Surveillance System Profile: The Kombewa Health and Demographic Surveillance System (Kombewa HDSS).

    PubMed

    Sifuna, Peter; Oyugi, Mary; Ogutu, Bernhards; Andagalu, Ben; Otieno, Allan; Owira, Victorine; Otsyula, Nekoye; Oyieko, Janet; Cowden, Jessica; Otieno, Lucas; Otieno, Walter

    2014-08-01

    The Kombewa Health and Demographic Surveillance System (HDSS) grew out of the Kombewa Clinical Research Centre in 2007 and has since established itself as a platform for the conduct of regulated clinical trials, nested studies and local disease surveillance. The HDSS is located in a rural part of Kisumu County, Western Kenya, and covers an area of about 369 km(2) along the north-eastern shores of Lake Victoria. A dynamic cohort of 141 956 individuals drawn from 34 718 households forms the HDSS surveillance population. Following a baseline survey in 2011, the HDSS continues to monitor key population changes through routine biannual household surveys. The intervening period between set-up and baseline census was used for preparatory work, in particular Global Positioning System (GPS) mapping. Routine surveys capture information on individual and households including residency, household relationships, births, deaths, migrations (in and out) and causes of morbidity (syndromic incidence and prevalence) as well as causes of death (verbal autopsy). The Kombewa HDSS platform is used to support health research activities, that is clinical trials and epidemiological studies evaluating diseases of public health importance including malaria, HIV and global emerging infectious diseases such as dengue fever. PMID:25009309

  16. A New Mechanism for Tracking Publicly Available Study Volunteer Demographics

    PubMed Central

    Zuckerman, Rachael; Getz, Kenneth; Kaitin, Kenneth

    2011-01-01

    The importance of gathering and monitoring aggregate demographic data on the annual population of study volunteers in FDA-regulated clinical trials is widely acknowledged. To date, no formal mechanism exists to capture this information. The Tufts Center for the Study of Drug Development identified and tested a publicly available source of information on clinical trial participant data, NDA Reviews stored in the FDA’s drugs@FDA database, to determine its accuracy, reliability, and feasibility. Thirty-seven new drug applications approved between 2006 and 2008 were evaluated and compared with published sources of demographic data. The authors conclude that the approach described here—NDA review extraction—provides reasonably reliable and conservative estimates of study volunteer demographics and can serve as a useful baseline until Clinicaltrials.gov or other, more complete, public sources become available. PMID:21625297

  17. Demographic outcomes and ecosystem implications of giant tortoise reintroduction to Espańola Island, Galapagos.

    PubMed

    Gibbs, James P; Hunter, Elizabeth A; Shoemaker, Kevin T; Tapia, Washington H; Cayot, Linda J

    2014-01-01

    Restoration of extirpated species via captive breeding has typically relied on population viability as the primary criterion for evaluating success. This criterion is inadequate when species reintroduction is undertaken to restore ecological functions and interactions. Herein we report on the demographic and ecological outcomes of a five-decade-long population restoration program for a critically endangered species of "ecosystem engineer": the endemic Espańola giant Galapagos tortoise (Chelonoidis hoodensis). Our analysis of complementary datasets on tortoise demography and movement, tortoise-plant interactions and Espańola Island's vegetation history indicated that the repatriated tortoise population is secure from a strictly demographic perspective: about half of tortoises released on the island since 1975 were still alive in 2007, in situ reproduction is now significant, and future extinction risk is low with or without continued repatriation. Declining survival rates, somatic growth rates, and body condition of repatriates suggests, however, that resources for continued population growth are increasingly limited. Soil stable carbon isotope analyses indicated a pronounced shift toward woody plants in the recent history of the island's plant community, likely a legacy of changes in competitive relations between woody and herbaceous plants induced by now-eradicated feral goats and prolonged absence of tortoises. Woody plants are of concern because they block tortoise movement and hinder recruitment of cactus--a critical resource for tortoises. Tortoises restrict themselves to remnant cactus patches and areas of low woody plant density in the center of the island despite an apparent capacity to colonize a far greater range, likely because of a lack of cactus elsewhere on the island. We conclude that ecosystem-level criteria for success of species reintroduction efforts take much longer to achieve than population-level criteria; moreover, reinstatement of endangered species as fully functioning ecosystem engineers may often require large-scale habitat restoration efforts in concert with population restoration. PMID:25350744

  18. Demographic processes underlying subtle patterns of population structure in the scalloped hammerhead shark, Sphyrna lewini.

    PubMed

    Nance, Holly A; Klimley, Peter; Galván-Magańa, Felipe; Martínez-Ortíz, Jimmy; Marko, Peter B

    2011-01-01

    Genetic diversity (?), effective population size (N(e)), 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 N(e) (? = 4N(e)?), 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 N(e) 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. PMID:21789171

  19. Demographic Outcomes and Ecosystem Implications of Giant Tortoise Reintroduction to Espańola Island, Galapagos

    PubMed Central

    Gibbs, James P.; Hunter, Elizabeth A.; Shoemaker, Kevin T.; Tapia, Washington H.; Cayot, Linda J.

    2014-01-01

    Restoration of extirpated species via captive breeding has typically relied on population viability as the primary criterion for evaluating success. This criterion is inadequate when species reintroduction is undertaken to restore ecological functions and interactions. Herein we report on the demographic and ecological outcomes of a five-decade-long population restoration program for a critically endangered species of “ecosystem engineer”: the endemic Espańola giant Galapagos tortoise (Chelonoidis hoodensis). Our analysis of complementary datasets on tortoise demography and movement, tortoise-plant interactions and Espańola Island’s vegetation history indicated that the repatriated tortoise population is secure from a strictly demographic perspective: about half of tortoises released on the island since 1975 were still alive in 2007, in situ reproduction is now significant, and future extinction risk is low with or without continued repatriation. Declining survival rates, somatic growth rates, and body condition of repatriates suggests, however, that resources for continued population growth are increasingly limited. Soil stable carbon isotope analyses indicated a pronounced shift toward woody plants in the recent history of the island’s plant community, likely a legacy of changes in competitive relations between woody and herbaceous plants induced by now-eradicated feral goats and prolonged absence of tortoises. Woody plants are of concern because they block tortoise movement and hinder recruitment of cactus–a critical resource for tortoises. Tortoises restrict themselves to remnant cactus patches and areas of low woody plant density in the center of the island despite an apparent capacity to colonize a far greater range, likely because of a lack of cactus elsewhere on the island. We conclude that ecosystem-level criteria for success of species reintroduction efforts take much longer to achieve than population-level criteria; moreover, reinstatement of endangered species as fully functioning ecosystem engineers may often require large-scale habitat restoration efforts in concert with population restoration. PMID:25350744

  20. Cellular Pressure-Actuated Joint

    NASA Technical Reports Server (NTRS)

    McGuire, John R.

    2003-01-01

    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.

  1. History Channel: This Day in History

    NSDL National Science Digital Library

    For those looking to find out about a variety of important historical events on a particular day, this site provided by the History Channel will be both entertaining and informative. This Day in History collects information about historical events organized around a number of topical sections, such as Cold War History, Literary History, Old West History, Technology History, Wall Street History, and Civil War History. Along with brief essays describing the events of a particular day, some of the more recent events also have short video clips that users can watch. On one recent day (January 28th), events covered included the tragic explosion of the Challenger space shuttle in 1986 and the United States' failure to capture Pancho Villa, the Mexican revolutionary. Visitors can also type in their birthdays to find out about events that occurred on that day, as well as for a list of well-known persons who share their birthday.

  2. Ecotoxicology and Environmental Safety 69 (2008) 227232 Life-history trade-offs of Paronychiurus kimi (Lee) (Collembola

    E-print Network

    Neher, Deborah A.

    2008-01-01

    kimi (Lee) (Collembola: Onychiuridae) populations exposed to paraquat Won Il Choia,Ă, Deborah A. Nehera and reproductive period. It is suggested that these are potential life-history tradeoffs of Collembola that were rights reserved. Keywords: Collembola; Demographical bioassay; Fitness; Herbicide; Life history; Paraquat

  3. Demographic Detail Transmittal Form (U5605) In order to comply with the federal reporting requirements, the University of California uses the demographic data transmittal form

    E-print Network

    Walker, Matthew P.

    Demographic Detail Transmittal Form (U5605) In order to comply with the federal reporting requirements, the University of California uses the demographic data transmittal form (U5605) to record the U5605 "Demographic Data Transmittal" on which they are asked to self-identify their ethnicity

  4. Phase 1 Program Joint Report

    NASA Technical Reports Server (NTRS)

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

    1999-01-01

    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.

  5. Joint Communiqu Progress against the

    E-print Network

    1 Joint Communiqué Progress against the Joint Statement of Cooperation between Kalimantan Timur the Joint Statement of Cooperation of 16 September 2010 designed to develop closer ties between Kalimantan the following areas: Livestock Following the 2010 Livestock Workshop held in Balikpapan, a Kalimantan Timur

  6. Joint Seminar UNIVERSITY OF GEORGIA

    E-print Network

    Wang, Lily

    Joint Seminar UNIVERSITY OF GEORGIA DEPARTMENT OF STATISTICS DEPARTMENT OF EPIDEMIOLOGY longitudinal covariates are involved in the modeling of the survival data. A joint likelihood approach has been data. However, in the presence of left truncation, there are additional challenges for the joint

  7. JOINT PERFORMANCE Guide for Optimum

    E-print Network

    July 2012 JOINT PERFORMANCE Guide for Optimum of Concrete Pavements #12; #12;Guide for Optimum Joint Performance of Concrete Pavements i Technical Report Documentation Page 1. Report No. 2. Report Date Guide for Optimum Joint Performance of Concrete Pavements July 2012 6. Performing

  8. Demographic, epidemiological, and health transitions: are they relevant to population health patterns in Africa?

    PubMed Central

    Kuate Defo, Barthélémy

    2014-01-01

    Background Studies of trends in population changes and epidemiological profiles in the developing world have overwhelmingly relied upon the concepts of demographic, epidemiological, and health transitions, even though their usefulness in describing and understanding population and health trends in developing countries has been repeatedly called into question. The issue is particularly relevant for the study of population health patterns in Africa and sub-Saharan Africa, as the history and experience there differs substantially from that of Western Europe and North America, for which these concepts were originally developed. Objective The aim of this study is two-fold: to review and clarify any distinction between the concepts of demographic transition, epidemiological transition and health transition and to identify summary indicators of population health to test how well these concepts apply in Africa. Results Notwithstanding the characteristically diverse African context, Africa is a continent of uncertainties and emergencies where discontinuities and interruptions of health, disease, and mortality trends reflect the enduring fragility and instability of countries and the vulnerabilities of individuals and populations in the continent. Africa as a whole remains the furthest behind the world's regions in terms of health improvements and longevity, as do its sub-Saharan African regions and societies specifically. This study documents: 1) theoretically and empirically the similarities and differences between the demographic transition, epidemiological transition, and health transition; 2) simple summary indicators that can be used to evaluate their descriptive and predictive features; 3) marked disparities in the onset and pace of variations and divergent trends in health, disease, and mortality patterns as well as fertility and life expectancy trajectories among African countries and regions over the past 60 years; 4) the rapid decline in infant mortality and gains in life expectancy from the 1950s through the 1990s in a context of preponderant communicable diseases in all African countries; 5) the salient role of adult mortality, mostly ascribed to HIV/AIDS and co-morbidities, since the 1990s in reversing trends in mortality decline, its interruption of life expectancy improvements, and its reversal of gender differences in life expectancies disadvantaging women in several countries with the highest prevalence of HIV/AIDS; 6) the huge impact of wars in reversing the trends in under-five mortality decline in sub-Saharan countries in the 1990s and beyond. These assessments of these transition frameworks and these phenomena were not well documented to date for all five regions and 57 countries of Africa. Conclusion Prevailing frameworks of demographic, epidemiological, and health transitions as descriptive and predictive models are incomplete or irrelevant for charting the population and health experiences and prospects of national populations in the African context. PMID:24848648

  9. Pupils' Conceptions of History and History Teaching

    Microsoft Academic Search

    Nadine Fink

    We present the results from qualitative analysis of eight interviews with 15 years old pupils about their conceptions of history and history teaching. These interviews were conducted as an extension of a survey conducted by a social sciences didactics team from the University of Geneva under Professor Audigier's direction. We first analyse what pupils think about the utility of history

  10. History of Silk

    NSDL National Science Digital Library

    0000-00-00

    Nicely illustrated history of silk and explanation of silk production. A fine discussion of the moths, life history, and feeding are included, as well as the extensive cultural history of this outstanding insect product.

  11. Department of History Conference

    E-print Network

    van den Berg, Jur

    Department of History Conference 2013 PRACTICING HISTORY #12; CTIHB RoomDannell Obsessed by History: Mormons and the Heritage Industry Sam DeMonja From Room 351 Moderator: James Lehning Ginger Smoak Midwives

  12. Functional traits explain variation in plant life history strategies.

    PubMed

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

    2014-01-14

    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

  13. 47 CFR 76.912 - Joint certification.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ...912 Joint certification. (a) Franchising authorities may apply for joint...data collection, and ratemaking. Franchising authorities jointly certified to regulate...independent rate decisions. (b) Franchising authorities may apply for joint...

  14. 47 CFR 76.912 - Joint certification.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ...912 Joint certification. (a) Franchising authorities may apply for joint...data collection, and ratemaking. Franchising authorities jointly certified to regulate...independent rate decisions. (b) Franchising authorities may apply for joint...

  15. Joint Degrees & Promotion towards European Students

    E-print Network

    Di Pillo, Gianni

    Joint Degrees & Promotion towards European Students 26 June 2014 MATTEA CAPELLI & ALESSANDRA GALLERANO INTERNATIONAL OFFICE #12;Joint Degrees and Promotion towards European students Joint degrees guidelines and template for agreements Support to student participation Promotion of Joint Degrees towards

  16. Localized pigmented villonodular synovitis of the proximal tibiofibular joint.

    PubMed

    Kwon, Jae Ho; Han, Jae Hwi; Almeida, Vivian Rd'; Kim, Seong Hyun; Park, Hai Jin; Nha, Kyung-Wook

    2014-12-01

    Pigmented villonodular synovitis (PVNS) is a rare disease. It is a benign neoplastic process typically affecting young to middle-aged adults and most commonly involving the knee, hip, and shoulder joints. The symptoms include diffuse pain and swelling with discomfort. We report a rare case of localized PVNS originating at the proximal tibiofibular joint in a 39-year-old female patient with radiologic changes for short duration of time. The clinical history, plain radiographs, magnetic resonance imaging, and pathologic findings of the reported patient were reviewed. Complete surgical excision was performed and there was no evidence of recurrence after one-year follow-up. PMID:25505708

  17. Temporomandibular joint disorder and inner ear pruritus: resolution by eminectomy.

    PubMed

    Pentyala, Sahana; Mysore, Pooja; Moller, Daryn; Pentyala, Srinivas; Kardovich, Richard; Martino, Andrew; Proothi, Michael

    2014-09-01

    Recurrent dislocation of the temporomandibular joint (TMJ) disk is caused by many factors. Dislocation can result in an acute or chronic closed lock condition. Temporomandibular joint dysfunction is often presented with otalgia symptoms. Other aural symptoms such as deafness, tinnitus, pressure/blockage, and vertigo are also commonly presented together with TMJ dysfunction (Clin Otolaryngol Allied Sci. 1980;5:23-36). However, pruritus associated with TMJ dysfunction in the inner ear has never been reported in the literature. We report a case history of TMJ dysfunction and associated inner ear pruritus, which are both resolved by eminectomy. PMID:25072971

  18. Demographics, assessment and management of pain in the elderly.

    PubMed

    Davis, Mellar P; Srivastava, Manish

    2003-01-01

    The prevalence of pain increases with each decade of life. Pain in the elderly is distinctly different from pain experienced by younger individuals. Cancer is a leading cause of pain; however, other conditions that cause pain such as facet joint arthritis (causing low back pain), polymyalgia rheumatica, Paget's disease, neuropathies, peripheral vascular disease and coronary disease most commonly occur in patients over the age of 50 years. Poorly controlled pain in the elderly leads to cognitive failure, depression and mood disturbance and reduces activities of daily living. Barriers to pain management include a sense of fatalism, denial, the desire to be 'the good patient', geographical barriers and financial limitations. Aging causes physiological changes that alter the pharmacokinetics and pharmacodynamics of analgesics, narrowing their therapeutic index and increasing the risk of toxicity and drug-drug interactions. CNS changes lead to an increased risk of delirium. Assessment among the verbal but cognitively impaired elderly is satisfactorily accomplished with the help of unidimensional and multidimensional pain scales. A comprehensive physical examination and pain history is essential, as well as a review of cognitive function and activities of daily living. The goal of pain management among the elderly is improvement in pain and optimisation of activities of daily living, not complete eradication of pain nor the lowest possible drug dosages. Most successful management strategies combine pharmacological and nonpharmacological (home remedies, massage, topical agents, heat and cold packs and informal cognitive strategies) therapies. A basic principle of the pharmacological approach in the elderly is to start analgesics at low dosages and titrate slowly. The WHO's three-step guideline to pain management should guide prescribing. Opioid choices necessitate an understanding of pharmacology to ensure safe administration in end-organ failure and avoidance of drug interactions. Adjuvant analgesics are used to reduce opioid adverse effects or improve poorly controlled pain. Adjuvant analgesics (NSAIDs, tricyclic antidepressants and antiepileptic drugs) are initiated prior to opioids for nociceptive and neuropathic pain. Preferred adjuvants for nociceptive pain are short-acting paracetamol (acetaminophen), NSAIDs, cyclo-oxygenase-2 inhibitors and corticosteroids (short-term). Preferred drugs for neuropathic pain include desipramine, nortriptyline, gabapentin and valproic acid. Drugs to avoid are pentazocine, pethidine (meperidine), dextropropoxyphene and opioids that are both an agonist and antagonist, ketorolac, indomethacin, piroxicam, mefenamic acid, amitriptyline and doxepin. The type of pain, and renal and hepatic function, alter the preferred adjuvant and opioid choices. Selection of the appropriate analgesics is also influenced by versatility, polypharmacy, severity and type of pain, drug availability, associated symptoms and cost. PMID:12513114

  19. Achieving joint benefits from joint implementation

    SciTech Connect

    Moomaw, W.R. [Tufts Univ., Medford, MA (United States)

    1995-11-01

    Joint Implementation (JI) appears to have been born with Applied Energy Services Guatemala project in 1988. That project, to plant 52 million trees, protect existing forests from cutting and fire, and enhance rural development, is being implemented by CARE Guatemala to offset 120 per cent of the emissions of a small coal burning power plant that has been built in Connecticut. Since that time, several utilities and governments have initiated additional projects. Not all of these necessarily consist of tree planting in other countries, but may consist of energy efficiency or energy conservation programs designed to reduce carbon emissions by at least as much as the additional releases from a new facility. All JI projects share the characteristic of linking the release of greenhouse gases in an industrial country with an offset that reduces or absorbs a comparable amount in another country. The emitter in the industrial country is willing to pay for the reduction elsewhere because costs are less than they would be at home.

  20. DEMOGRAPHIC PLASTICITY IN RELATION TO GROWTH AND RESOURCE ALLOCATION PATTERN IN ANTHEMIS COTULA AN ALIEN INVASIVE SPECIES IN KASHMIR HIMALAYA, INDIA

    Microsoft Academic Search

    R. R. ALLAIE-Z. RESHI; B. A. WAFAI

    2005-01-01

    The demographic study of Anthemis cotula L. revealed a protracted seedling recruitment pattern with peaks in autumn (pre-winter) and spring (post-winter). The major recruitment pulse in autumn contributes to the fecundity component of the life history while the minor recruitment pulse in spring aids in survival of the species. The total drymass accumulation shows striking variations between the pre-winter and

  1. Laboratory characterization of rock joints

    SciTech Connect

    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

    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.

  2. Collective and joint intention

    Microsoft Academic Search

    Raimo Tuomela; Joint Intentions

    2000-01-01

    The paper discussed and analyzes collective and joint intentions of various strength. Thus there are subjectively shared collective\\u000a intentions and intersubjectively shared collective intentions as well as collective intentions which are objectively and intersubjectively\\u000a shared. The distinction between collective and private intentions is considered from several points of view. Especially, it\\u000a is emphasized that collective intentions in the full sense

  3. Relationship among Demographic Variables and Pupils' Reasoning Ability

    ERIC Educational Resources Information Center

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

    2008-01-01

    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)…

  4. Mule Deer Demographic Responses to Select Climatic Variables in Arizona

    Microsoft Academic Search

    Brian F. Wakeling

    To determine what effect climate has potentially had on recent demographic shifts and population declines of mule deer in Arizona, I studied the relationship of monthly precipitation and Palmer Drought Severity Index (PDSI) values with Arizona Game and Fish Department winter mule deer (Odocoileus hemionus) survey fawn:doe (FDR) and buck:doe (BDR) ratio data. Seven of 37 Game Management Units (GMUs)

  5. Details from the Dashboard: Charter School Race/Ethnicity Demographics

    ERIC Educational Resources Information Center

    National Alliance for Public Charter Schools, 2012

    2012-01-01

    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…

  6. Demographics of Deaf Education: More Students in More Places

    ERIC Educational Resources Information Center

    Mitchell, R. E., Karchmer, M. A.

    2006-01-01

    We have witnessed important changes in the demographics of the deaf and hard of hearing student population receiving special education services during the past quarter century. The ethnic, intervention, and educational setting profiles are more diverse and dispersed. On top of the federal policy changes driving emerging intervention and continuing…

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

    ERIC Educational Resources Information Center

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

    2008-01-01

    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…

  8. Demographic Techniques for Manpower Planning in Developing Countries.

    ERIC Educational Resources Information Center

    Bureau of Employment Security (DOL), Washington, DC.

    This handbook explains major demographic techniques which can be used by developing countries to estimate total population and to make projections of population changes. The data were devised for field analysts who have limited mathematical and statistical backgrounds. Anyone with a knowledge of addition, subtraction, multiplication, division, and…

  9. Demographic matrix model for swallow-wort (Vincetoxicum spp.)

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Demographic matrix modeling of plant populations can be a powerful tool to identify key life stage transitions that contribute the most to population growth of an invasive plant and hence should be targeted for disruption (weak links) by biological control and/or other control tactics. Therefore, t...

  10. Do Online Learning Patterns Exhibit Regional and Demographic Differences?

    ERIC Educational Resources Information Center

    Hsieh, Tsui-Chuan; Yang, Chyan

    2012-01-01

    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…

  11. Demographic trends and international capital flows in an integrated world

    Microsoft Academic Search

    Luca Marchiori

    2011-01-01

    This paper examines the impact of projected demographic trends on international capital flows. The analysis builds upon a ten-region overlapping generations' model of the world economy where capital is mobile across regions. Results show that, over the first half of the century, emerging regions will finance the demand of capital coming from the developed world where population aging is relatively

  12. The Russian Market of University Services: Social and Demographic Aspects

    ERIC Educational Resources Information Center

    Bydanova, Elizaveta; Mushketova, Natalia; Rouet, Gilles

    2015-01-01

    Purpose: The purpose of this paper is to analyze the impact of demographic, social, economic and international aspects on the market of university services in Russia. It also reminds readers briefly of the evolution of the Russian higher education system during the last 20 years and considers some consequences of the current public policy and…

  13. Students from Australian Universities Studying Abroad: A Demographic Profile

    ERIC Educational Resources Information Center

    Nerlich, Steve

    2015-01-01

    Australia is one of many countries to encourage its students to study abroad and hence develop a global perspective. Traditionally, students who have pursued this option represented a relatively privileged and demographically narrow group. More recently, governments and other agencies have been offering funding support with the aim of…

  14. A Demographic and Career Profile of Canadian Research University Librarians

    ERIC Educational Resources Information Center

    Fox, David

    2007-01-01

    This paper provides an up-to-date career and demographic profile of Canadian research university librarians by comparing newly derived data from the 8Rs Study: The "Future of Human Resources in Canadian Libraries", with corresponding information from the author's 2006 survey: "The Scholarship of Canadian Research University Librarians", and other…

  15. Understanding the Demographics of Twitter Users Alan Mislove

    E-print Network

    Ahn, Yong-Yeol

    Understanding the Demographics of Twitter Users Alan Mislove Sune Lehmann Yong-Yeol Ahn Jukka are recorded in the form of 140-character tweets using Twitter. However, despite the enormous poten- tial presented by this remarkable data source, we still do not have an understanding of the Twitter population

  16. Handicap Parking: A Demographic Study of Legal and Illegal Users.

    ERIC Educational Resources Information Center

    Bordeaux, Monica N.; And Others

    Studies on handicap parking reveal the existence of a significant problem of unauthorized use of designated handicap spaces. This study examined various demographic variables involved in the illegal use of handicap parking spaces. Subjects (N=266) were drivers of vehicles observed in handicap parking spaces in three grocery store parking lots.…

  17. Are We Ready for the Approaching Demographic Tsunami?

    ERIC Educational Resources Information Center

    Vargas, Bolgen; Conlon, Jill E.

    2011-01-01

    For those at the high school and college levels who have been tracking the demographic changes occurring throughout the United States during the past few decades, it came as no surprise when recent U.S. Census statistics revealed that the 2010 kindergarten class is 25% Hispanic, up from 19% in 2000, and 5% Asian, up from 4% in 2000. The class is…

  18. Demographic and Organizational Variables as Predictors of Teacher Attrition

    ERIC Educational Resources Information Center

    Watkins, Leah Rice

    2013-01-01

    The purpose of this study was to examine the predictive capacity of specific demographic and organizational variables upon teacher attrition from the profession. The study examined the possibility of predicting attrition of teachers based upon these variables. Furthermore, the study attempted to create a profile of the most likely teachers to…

  19. The demographics of occupational stress among police superintendents

    Microsoft Academic Search

    Bruce Kirkcaldy; Jennifer Brown; Cary L. Cooper

    1998-01-01

    The relationship between diverse demographic variables and the occupational stress indicator subscales (Cooper et al., 1988) were examined among several hundred UK senior police officers. Officers who prior to their promotion to superintendent had spent most of their time within the criminal detective branch displayed the highest Type A behaviour (aggressive, dominant and assertive), and traffic officers the worst subjective

  20. Demographic, Biologic, and Other Variables Affecting Monoamine Oxidase Activity

    Microsoft Academic Search

    Donald S. Robinson; Alexander Nies

    1980-01-01

    Monoamine oxidase (MAO) activity has been shown to be influenced by a variety of demographic, biologic, and other variables. Human platelet, plasma, and brain enzyme activities correlate with age and are higher in women. Brain catecholamines tend to decrease with age. The acute effects of ethanol on platelet MAO do not appear to be significant, but chronic ethanol ingestion could

  1. Creating a Database for Demographic Research: A Case Study.

    ERIC Educational Resources Information Center

    Gates, William A.; Witt, Barbara

    The PUS801000 (Public Use Samples) database was created as a subsample of the Census Bureau's 1980 Public Use Microdata Sample (PUMS) for the purpose of meeting the needs of demographics research. PUMS needed to be reorganized along relational lines by identifying the variables most widely used by researchers and constructing proper relations…

  2. Management and Conservation Article Demographic Sensitivity of Population Change in

    E-print Network

    Sandercock, Brett K.

    , management, or control. Two types of stochastic population models in widespread use include the parametricManagement and Conservation Article Demographic Sensitivity of Population Change in Northern that is currently undergoing widespread population declines. Despite considerable research on the population ecology

  3. Demographics and Diversity of Asian American College Students.

    ERIC Educational Resources Information Center

    Hune, Shirley

    2002-01-01

    The author provides an overview of the Asian American population, its immigration patterns and trends, current demographics, and higher educational statistics and explains why student affairs professionals need to address the diversity of Asian American students if they are to be better served and supported. (Contains 16 references.) (Author)

  4. Demographics and Industry Employment of Civil Engineering Workforce

    Microsoft Academic Search

    Neil S. Grigg

    2000-01-01

    This paper provides a road map to studies and databases about civil engineering demographics and industry involvement by tracing workforce statistics, engineering degrees, data on industries and government, and economic forecasts. It is aimed at helping civil engineering managers, educators, and policy makers under- stand how their workforce evolved and what it will face in the future. The engineering workforce

  5. Socio-demographics, activity participation and travel behavior

    Microsoft Academic Search

    Xuedong Lu; Eric I. Pas

    1999-01-01

    This paper describes the development, estimation and interpretation of a model relating socio-demographics, activity participation (time use) and travel behavior. A complex set of interrelationships among the variables of interest is estimated simultaneously using the structural equation modeling methodology, with activity participation (time allocated to a number of activity types) and travel behavior endogenous to the model. The research reported

  6. Asia's demographic miracle: 50 years of unprecedented change.

    PubMed

    Leete, R; Alam, I

    1999-12-01

    The demographic landscape of Asia has seen unprecedented changes over the past 50 years. The transition from high to low mortality and fertility rates has made the eventual stabilization of the world's population a real possibility. The demographic success of Asia is associated with the stunning economic and social changes that have taken place during this period. Aside from social and economic improvements, population and health policies also played a major part in shaping the region's demographic transformation. National programs made a substantial contribution to increasing contraceptive use, lowering fertility, and slowing population growth. The success of family planning programs was frequently supported by positive changes in the demand for children. As the initial impact of the recent financial and economic crisis has shown, the Asian demographic miracle cannot be taken for granted. Since mid-1997, the crisis has interrupted and reversed the region's remarkable development gains. Economic downturns often tend to affect the social sectors unevenly. Strengthening the provision of basic social services, including reproductive health and care of the elderly, particularly in poor nations, will remain a challenge in the next century. The establishment of goals, including in areas such as HIV/AIDS, will help Asian countries realize the vision of the International Conference on Population and Developmentżs 20-year Programme of Action. PMID:12349488

  7. Tobacco Sales in Community Pharmacies: Remote Decisions and Demographic Targets

    ERIC Educational Resources Information Center

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

    2010-01-01

    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…

  8. DEMOGRAPHIC ANALYSIS ON ATLANTIC BLUE AND SHORTFIN MAKO SHARKS

    Microsoft Academic Search

    Yukio Takeuchi; Yasuko Senba; Hideki Nakano

    2005-01-01

    SUMMARY Demographic analysis on Atlantic blue shark and shortfin mako shark was done. Uncertainties of input parameters were accounted by Monte Carlo simulation. Current total mortality of those sharks was estimated by catch curve analysis applied to catch at age data of Japanese longline observer data. The results suggested that current fishing mortality on blue shark is sustainable. As for

  9. Demographic and motivation variables associated with Internet usage activities

    Microsoft Academic Search

    Thompson S. H. Teo

    2001-01-01

    Examines demographic variables (gender, age, educational level) and motivation variables (perceived ease of use, perceived enjoyment, perceived usefulness) associated with Internet usage activities (defined in terms of messaging, browsing, downloading and purchasing). A total of 1,370 usable responses were obtained using a Web page survey. Results showed that males are more likely to engage in downloading and purchasing activities while

  10. Predicting Discontinuation in Psychotherapy Via Psychometric and Demographic Variables.

    ERIC Educational Resources Information Center

    Sheehan, Edward

    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

  11. Developing an Information System for Graduate Student Demographic Data.

    ERIC Educational Resources Information Center

    Midkiff, Karen R.

    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…

  12. Demographic and Social Predictors of Intimate Partner Violence in Colombia

    E-print Network

    Jones, James Holland

    Demographic and Social Predictors of Intimate Partner Violence in Colombia A Dyadic Power, and Colombia (Flake and Forste 2006). In Peru, low educational attainment and early union formation increase-dominant decision-making was associated with higher risk of IPV in Nicaragua, Haiti, and Colombia. The welter

  13. RESEARCH Open Access Testing for fertility stalls in demographic and

    E-print Network

    Paris-Sud XI, Université de

    RESEARCH Open Access Testing for fertility stalls in demographic and health surveys Michel L Garenne1,2,3 Abstract This study compares two methods for testing fertility trends and fertility stalls the equivalence of period and cohort estimates with the same cumulative fertility at age 40, the same number

  14. Heterogeneity influences spatial patterns and demographics in forest stands

    Microsoft Academic Search

    Stephan Getzin; Thorsten Wiegand; Kerstin Wiegand; Fangliang He

    2008-01-01

    Summary 1. The spatial pattern of tree species retains signatures of factors and processes such as dispersal, available resource patches for establishment, competition and demographics. Comparison of the spatial pattern of different size classes can thus help to reveal the importance and characteristics of the underlying processes. However, tree dynamics may be masked by large-scale heterogeneous site conditions, e.g. when

  15. Demographic, Criminal, and Psychiatric Factors Related to Inmate Suicide

    ERIC Educational Resources Information Center

    Blaauw, Eric; Kerkhof, Ad J. F. M.; Hayes, Lindsay M.

    2005-01-01

    A review of 19 studies suggests that it may be feasible to identify prisoners with suicide risk on the basis of demographic, psychiatric, and criminal characteristics. The present study aimed to identify combinations of characteristics that are capable of identifying potential suicide victims. Characteristics of 95 suicide victims in the Dutch…

  16. Demographic Forces Reshaping Small Communities in the 1980s.

    ERIC Educational Resources Information Center

    Morrison, Peter A.; McCarthy, Kevin F.

    Demographic and socioeconomic changes are reshaping the fortunes of small communities and pose policy issues. Such communities find it especialy difficult to deal with rapid growth or decline, or a switch from one to the other. Small communities now enjoy greater autonomy, but at the cost of reduced federal aid. Freed from federal mandates, each…

  17. Post Secondary Education Planning: The Demographic Context. A Discussion Paper.

    ERIC Educational Resources Information Center

    Jones, Evan; And Others

    The demographic context that will affect postsecondary education in Western Australia is examined, with attention to recent trends in population growth as well as population distribution and projections to the year 2021. The analysis is based on the 1981 Population and Housing Census and population projections of the Australian Bureau of…

  18. Demographics of Dietitians Using an on-Line Service

    Microsoft Academic Search

    K. Ziemer; J. Homer-Trobaugh; G. Forsell

    1995-01-01

    An electronic bulletin board dedicated to dietetics professionals was started on AOL by several RDs in December 1994. In order to plan group activities that would meet the needs of dietetics professionals using the service, a survey of demographic information was conducted. RDs surveyed were identified either as participants in the RD Network, or by a search of the AOL

  19. Progressive Damage Modeling of Durable Bonded Joint Technology

    NASA Technical Reports Server (NTRS)

    Leone, Frank A.; Davila, Carlos G.; Lin, Shih-Yung; Smeltzer, Stan; Girolamo, Donato; Ghose, Sayata; Guzman, Juan C.; McCarville, Duglas A.

    2013-01-01

    The development of durable bonded joint technology for assembling composite structures for launch vehicles is being pursued for the U.S. Space Launch System. The present work is related to the development and application of progressive damage modeling techniques to bonded joint technology applicable to a wide range of sandwich structures for a Heavy Lift Launch Vehicle. The joint designs studied in this work include a conventional composite splice joint and a NASA-patented Durable Redundant Joint. Both designs involve a honeycomb sandwich with carbon/epoxy facesheets joined with adhesively bonded doublers. Progressive damage modeling allows for the prediction of the initiation and evolution of damage. For structures that include multiple materials, the number of potential failure mechanisms that must be considered increases the complexity of the analyses. Potential failure mechanisms include fiber fracture, matrix cracking, delamination, core crushing, adhesive failure, and their interactions. The joints were modeled using Abaqus parametric finite element models, in which damage was modeled with user-written subroutines. Each ply was meshed discretely, and layers of cohesive elements were used to account for delaminations and to model the adhesive layers. Good correlation with experimental results was achieved both in terms of load-displacement history and predicted failure mechanisms.

  20. Joint measurements and Bell inequalities

    E-print Network

    Wonmin Son; Erika Andersson; Stephem M. Barnett; M. S. Kim

    2005-09-20

    Joint quantum measurements of non-commuting observables are possible, if one accepts an increase in the measured variances. A necessary condition for a joint measurement to be possible is that a joint probability distribution exists for the measurement. This fact suggests that there may be a link with Bell inequalities, as these will be satisfied if and only if a joint probability distribution for all involved observables exists. We investigate the connections between Bell inequalities and conditions for joint quantum measurements to be possible. Mermin's inequality for the three-particle Greenberger-Horne-Zeilinger state turns out to be equivalent to the condition for a joint measurement on two out of the three quantum systems to exist. Gisin's Bell inequality for three co-planar measurement directions, meanwhile, is shown to be less strict than the condition for the corresponding joint measurement.

  1. Gynecological Surgery and Low Back Pain in Older Women: Testing the Association With Sacroiliac Joint Stiffness and Pelvic Floor Movements

    Microsoft Academic Search

    Jeffery Ericksen; Peter E. Pidcoe; Jessica M. Ketchum-McKinney; Evie N. Burnet; Emily Huang; James C. Wilson; Vincent Hoogstad

    2010-01-01

    Objective: To determine sacroiliac joint compliance characteristics and pelvic floor movements in older women relative to gynecological surgery history and back pain complaints. Design: Single-visit laboratory measurement. Setting: University clinical research center. Participants: Twenty-five women aged 65 years or older. Outcome Measures: Sacroiliac joint compliance measured by Doppler imaging of vibrations and ultrasound measures of pelvic floor motion during the

  2. Prevalence of Facet Joint Degeneration in Association with Intervertebral Joint Degeneration in a Sample of Organ Donors

    PubMed Central

    Muehleman, Carol; Li, Jun; Abe, Yumiko; Masuda, Koichi

    2011-01-01

    Among the most common causes of low back pain are strain on the muscles and ligaments associated with the spine, degeneration of the intervertebral discs (IVD), and osteoarthritis of the facet joints. It is not clear, however, how these latter two conditions are related to each other in terms of their development during a patient’s lifetime. The facet joint is the sole synovial joint of the spine but because it is difficult to image its degenerative history as well as its relationship to other degenerative factors within the spine remain elusive. We compared the gross and histologic characteristics of the lumbar spine from a sample of organ donors to the integrity of their associated IVDs as assessed through magnetic resonance imaging. In our study sample, we found that facet joint degeneration was common, occurring as early as 15 years of age, while the IVD could still remain intact. Facet degeneration was more severe at the L4/5 level and progressed along with IVD degeneration with age. Because such early degenerative changes in the facet joint are somewhat surprising, degeneration of this joint should not be overlooked when assessing OA of the spine and causes of lower back pain. PMID:21360583

  3. Primates and the Evolution of Long-Slow Life Histories

    PubMed Central

    Jones, James Holland

    2011-01-01

    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. PMID:21959161

  4. Uplift Histories From River Profiles: Examples From Africa

    NASA Astrophysics Data System (ADS)

    Paul, J. D.; Roberts, G. G.; White, N.

    2010-12-01

    A general method for estimating uplift histories from river long profiles is described and applied. First, we describe a forward model which calculates the height variation along a river profile from a given history of uplift rate. We assume that the erosional process can be represented by a combination of advection and diffusion. Second, we solve the geologically more interesting inverse problem: to determine which uplift history minimises the misfit between calculated and observed river profiles. Uplift rates are allowed to vary smoothly both spatially and temporally. Finally, we jointly invert all major river profiles from a series of topographic swells in Madagascar and onshore Africa. Fits between calculated and observed river profiles are excellent; calculated uplift histories suggest that African swells, including the Bié and South African domes, grew rapidly in the last 30-40 million years. Uplift histories are shown to vary significantly from swell to swell, but cumulative uplift histories agree with independent geological estimates.

  5. 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.

  6. Sociocultural and Demographic Risk Factors for the Development of Multiple Sclerosis in Kuwait: A Case - Control Study

    PubMed Central

    Al-Shammri, Suhail N.; Hanna, Magdy G.; Chattopadhyay, Arpita; Akanji, Abayomi O.

    2015-01-01

    Introduction Immunological, genetic and environmental factors are believed to play important roles in the pathogenesis of Multiple Sclerosis (MS). There have been many studies on risk factors for MS but these have been mainly in Caucasian populations; robust studies in Arab populations remain relatively uncommon. This study therefore aimed to identify behavioral, socio-cultural, and demographic factors associated with development of MS in Kuwait, a high income Arab country, currently undergoing a demographic transition. Subjects and methods In this case- control study, 195 Kuwaiti MS patients and 146 healthy age and sex-matched controls were recruited. Both groups of subjects were interviewed using a structured questionnaire, in relation to anthropometric, socio-cultural and demographic data, residence during the 1990/91 Gulf War and current and past medical history, including medications. We also clinically evaluated, and retrospectively reviewed medical records of patients to derive appropriate clinical information, including associated chronic medical illness requiring long-term treatment. Results On multiple logistic regression analysis after adjustment for potential confounders including age, gender and BMI, in all the subjects, a positive associations prevail with presence of MS and some sociocultural and demographic factors, which included non-Bedouin ethnicity (AOR 2, 95% CI 1.0-3.9, p 0.049), positive family history of MS (AOR 10.6, 95% CI 3.0-36.9), p < 0.001), and low daily sunlight exposure of < 15min/day (AOR 5.3, 95% CI 2.7-10.5 p < 0.001). In addition, while 41.8% of MS patients indicated at least one comorbidity, only 26.8% of the controls reported any associated physical illness, with the suggestion that presence of certain comorbidities might increase MS risk (AOR 2.4, 95% CI 1.3-4.7, p < 0.001). Other risk variables such as smoking status and mode of routine outdoor dressing were not significant in all the MS subjects taken as a whole, but demonstrated variably positive associations in the MS subgroup classified as those with established disease and those who were newly diagnosed and drug naďve. Conclusions This study suggests that a positive family history of MS and presence of certain comorbidities appeared to be associated with an increased risk of developing MS. In contrast, relatively increased amount of daily sunlight exposure and Bedouin ethnicity appear to somewhat be protective. It is speculated that the relationship of sunlight exposure with MS might be due to vitamin D availability, and is deserving of further study. PMID:26132203

  7. Demographic and microbial characteristics of extrapulmonary tuberculosis cases diagnosed in Malatya, Turkey, 2001-2007

    PubMed Central

    2011-01-01

    Background Extrapulmonary tuberculosis (EPTB) has an increasing rate in Turkey. The reason remains largely unknown. A better understanding of the demographic and microbial characteristics of EPTB in the Turkish population would extend the knowledgebase of EPTB and allow us to develop better strategies to control tuberculosis (TB). Methods We retrospectively evaluated clinical and laboratory data of 397 bacteriologically-confirmed TB cases diagnosed during an eight year-period using by chi-square analysis and multivariate logistic regression model. Results Of the 397 study patients, 103 (25.9%) had EPTB and 294 (74.1%) had pulmonary tuberculosis (PTB). The most commonly seen two types of EPTB were genitourinary TB (27.2%) and meningeal TB (19.4%). TB in bone/joints, pleural cavity, lymph nodes, skin, and peritoneal cavity occurred at a frequency ranging from 9.7% to 10.7%. The age distribution was significantly different (P < 0.01) between PTB and EPTB, with patients older than 45 years tending to have an increased risk of EPTB. Furthermore, the distribution of different types of EPTB differed significantly among age groups (P = 0.03). Meningeal and bone and/or joint TB were more commonly observed among the male patients, while lymphatic, genitourinary, and peritoneal TB cases were more frequently seen among females. Unique strain infection was statistically significantly associated with EPTB (OR: 2.82, 95% CI [1.59, 5.00]) Conclusions EPTB accounted for a significant proportion of TB cases in Malatya, Turkey between 2001 and 2007. The current study has provided an insight into the dynamics of EPTB in Malatya, Turkey. However, the risk factors for having EPTB in Malatya, Turkey remain to be assessed in future studies using population-based or randomly selected sample. PMID:21385458

  8. On representations for joint moments using a joint coordinate system.

    PubMed

    O'Reilly, Oliver M; Sena, Mark P; Feeley, Brian T; Lotz, Jeffrey C

    2013-11-01

    In studies of the biomechanics of joints, the representation of moments using the joint coordinate system has been discussed by several authors. The primary purpose of this technical brief is to emphasize that there are two distinct, albeit related, representations for moment vectors using the joint coordinate system. These distinct representations are illuminated by exploring connections between the Euler and dual Euler bases, the "nonorthogonal projections" presented in a recent paper by Desroches et al. (2010, "Expression of Joint Moment in the Joint Coordinate System," ASME J. Biomech. Eng., 132(11), p. 11450) and seminal works by Grood and Suntay (Grood and Suntay, 1983, "A Joint Coordinate System for the Clinical Description of Three-Dimensional Motions: Application to the Knee," ASME J. Biomech. Eng., 105(2), pp. 136-144) and Fujie et al. (1996, "Forces and Moment in Six-DOF at the Human Knee Joint: Mathematical Description for Control," Journal of Biomechanics, 29(12), pp. 1577-1585) on the knee joint. It is also shown how the representation using the dual Euler basis leads to straightforward definition of joint stiffnesses. PMID:24008987

  9. Exome resequencing reveals signatures of demographic and adaptive processes across the genome and range of black cottonwood (Populus trichocarpa).

    PubMed

    Zhou, L; Bawa, R; Holliday, J A

    2014-05-01

    Extant variation in temperate and boreal plant species has been influenced by both demographic histories associated with Pleistocene glacial cycles and adaptation to local climate. We used sequence capture to investigate the role of these neutral and adaptive processes in shaping diversity in black cottonwood (Populus trichocarpa). Nucleotide diversity and Tajima's D were lowest at replacement sites and highest at intergenic sites, while LD showed the opposite pattern. With samples grouped into three populations arrayed latitudinally, effective population size was highest in the north, followed by south and centre, and LD was highest in the south followed by the north and centre, suggesting a possible northern glacial refuge. FST outlier analysis revealed that promoter, 5'-UTR and intronic sites were enriched for outliers compared with coding regions, while no outliers were found among intergenic sites. Codon usage bias was evident, and genes with synonymous outliers had 30% higher average expression compared with genes containing replacement outliers. These results suggest divergent selection related to regulation of gene expression is important to local adaptation in P. trichocarpa. Finally, within-population selective sweeps were much more pronounced in the central population than in putative northern and southern refugia, which may reflect the different demographic histories of the populations and concomitant effects on signatures of genetic hitchhiking from standing variation. PMID:24750333

  10. Microsatellite data show recent demographic expansions in sedentary but not in nomadic human populations in Africa and Eurasia.

    PubMed

    Aimé, Carla; Verdu, Paul; Ségurel, Laure; Martinez-Cruz, Begońa; Hegay, Tatyana; Heyer, Evelyne; Austerlitz, Frédéric

    2014-10-01

    The transition from hunting and gathering to plant and animal domestication was one of the most important cultural and technological revolutions in human history. According to archeologists and paleoanthropologists, this transition triggered major demographic expansions. However, few genetic studies have found traces of Neolithic expansions in the current repartition of genetic polymorphism, pointing rather toward Paleolithic expansions. Here, we used microsatellite autosomal data to investigate the past demographic history of 87 African and Eurasian human populations with contrasted lifestyles (nomadic hunter-gatherers, semi-nomadic herders and sedentary farmers). Likely due to the combination of a higher mutation rate and the possibility to analyze several loci as independent replicates of the coalescent process, the analysis of microsatellite data allowed us to infer more recent expansions than previous genetic studies, potentially resulting from the Neolithic transition. Despite the variability in their location and environment, we found consistent expansions for all sedentary farmers, while we inferred constant population sizes for all hunter-gatherers and most herders that could result from constraints linked to a nomadic or semi-nomadic lifestyle and/or competition for land between herders and farmers. As an exception, we inferred expansions for Central Asian herders. This might be linked with the arid environment of this area that may have been more favorable to nomadic herders than to sedentary farmers. Alternatively, current Central Asian herders may descent from populations who have first experienced a transition from hunter-gathering to sedentary agropastoralism, and then a second transition to nomadic herding. PMID:24518830

  11. Joint bone radiobiology workshop

    SciTech Connect

    Tomich, P.A. (ed.)

    1991-01-01

    The Joint Bone Radiobiology Workshop was held on July 12--13, 1991 in Toronto, Canada. This document contains the papers presented at the meeting. The five sections were: Dose-effects, Endogenous Cofactors, Tumorigenesis, New Methods and Medical Implications. The papers covered risk assessment, tissue distribution of radionuclides, lifetime studies, biological half-lifes, the influence of age at time of exposure, tumor induction by different radionuclides, microscopic localization of radionuclides, and nuclear medicine issues including tissue distribution in the skeleton and bone marrow transplantation. (MHB)

  12. Temporomandibular Joint Disorders

    NSDL National Science Digital Library

    Patient Education Institute

    This patient education program explains temporomandibular joint disorders (TMJ). It reviews the anatomy of the jaw, plus symptoms, causes, diagnosis, and treatment options for TMJ disorders. This resource is a MedlinePlus Interactive Health Tutorial from the National Library of Medicine, designed and developed by the Patient Education Institute. NOTE: This tutorial requires a special Flash plug-in, version 4 or above. If you do not have Flash, you will be prompted to obtain a free download of the software before you start the tutorial. You will also need an Acrobat Reader, available as a free download, in order to view the Reference Summary.

  13. Bladder operated robotic joint

    NASA Technical Reports Server (NTRS)

    Robertson, Glen A. (inventor)

    1993-01-01

    This invention is a robotic joint which is operated by inflatable bladders and which can be used in applications where it is desired to move or hold an object. A support block supports an elongated plate to which is pivotally attached a finger. A tension strip passes over a lever attached to the finger and is attached at its ends to the support block on opposite sides of the plate. Bladders positioned between the plate and the tension strip on opposite sides of the plate can be inflated by pumps to pivot the finger, with one of the bladders being inflated while the other is being deflated.

  14. Metal to ceramic sealed joint

    DOEpatents

    Lasecki, John V. (Livonia, MI); Novak, Robert F. (Farmington Hills, MI); McBride, James R. (Ypsilanti, MI)

    1991-01-01

    A metal to ceramic sealed joint which can withstand wide variations in temperature and maintain a good seal is provided for use in a device adapted to withstand thermal cycling from about 20 to about 1000 degrees C. The sealed joint includes a metal member, a ceramic member having an end portion, and an active metal braze forming a joint to seal the metal member to the ceramic member. The joint is positioned remote from the end portion of the ceramic member to avoid stresses at the ends or edges of the ceramic member. The sealed joint is particularly suited for use to form sealed metal to ceramic joints in a thermoelectric generator such as a sodium heat engine where a solid ceramic electrolyte is joined to metal parts in the system.

  15. Strength of Welded Aircraft Joints

    NASA Technical Reports Server (NTRS)

    Brueggeman, W C

    1937-01-01

    This investigation is a continuation of work started in 1928 and described in NACA-TR-348 which shows that the insertion of gusset plates was the most satisfactory way of strengthening a joint. Additional tests of the present series show that joints of this type could be improved by cutting out the portion of the plate between the intersecting tubes. T and lattice joints in thin-walled tubing 1 1/2 by 0.020 inch have somewhat lower strengths than joints in tubing of greater wall thickness because of failure by local buckling. In welding the thin-walled tubing, the recently developed "carburizing flux" process was found to be the only method capable of producing joints free from cracks. The "magnetic powder" inspection was used to detect cracks in the joints and flaws in the tubing.

  16. Non-traumatic posterior atlanto-occipital joint dislocation.

    PubMed

    Takechi, Yasuhiko; Iizuka, Haku; Sorimachi, Yasunori; Ara, Tsuyoshi; Nishinome, Masahiro; Takagishi, Kenji

    2011-07-01

    This report presents a case of non-traumatic posterior atlanto-occipital dislocation. A 36-year-old female was referred with a history of numbness of the extremities, vertigo and neck pain for 1 year. The patient had no history of trauma. The axial rotation of range of motion of the cervical spine was severely restricted. A lateral cervical radiograph in the neutral position demonstrated a posterior atlanto-occipital dislocation. A coronal view on a computed tomography (CT) reconstruction image showed a loss of angle of the bilateral atlanto-occipital joint, and a sagittal reconstruction view of CT images also demonstrated flatness of atlanto-occipital joint. Instrumented occipito-cervical fusion was performed after reduction. A lateral cervical radiograph in the neutral position 1 year after surgery showed the reduction of atlanto-occipital joint, moreover, it was maintained even in an extended position. The patient had neurologic improvement after surgery. Flatness of the bilateral atlanto-occipital joint may have induced this instability. Occipital-cervical fusion was chosen in the present case since the patient showed restricted axial rotation of the neck before surgery. The surgery improved the preoperative symptoms including the function of cervical spine evaluated by JOACMEQ. PMID:20549257

  17. History of Studies on Mammalian Middle Ear Evolution: A

    E-print Network

    Sullivan, Jack

    History of Studies on Mammalian Middle Ear Evolution: A Comparative Morphological and Developmental for Developmental Biology, RIKEN, Kobe, Japan The mammalian middle ear represents one of the most fundamental middle ear was derived from elements of the jaw joint of nonmammalian amniotes. Fossils of mammalian

  18. OIG targets contractual joint ventures.

    PubMed

    O'Hare, Patrick K

    2003-09-01

    A recent OIG Special Advisory Bulletin raises questions for providers involved in joint ventures. The Bulletin describes several characteristics that the OIG views as potentially suspect, including a referral stream controlled by the provider initiating the joint venture and the use of a wholly owned subsidiary of the provider to bill and collect for services. According to the OIG, profits paid by the subsidiary to the provider owner in such "suspect contractual joint ventures" could constitute illegal remuneration for referrals. PMID:14503145

  19. The SDSS-IV in 2014: A Demographic Snapshot

    E-print Network

    Lundgren, Britt; Zasowski, Gail; Lucatello, Sara; Diamond-Stanic, Aleksandar M; Tremonti, Christy A; Myers, Adam D; Aragon-Salamanca, Alfonso; Gillespie, Bruce; Ho, Shirley; Gallagher, John S

    2015-01-01

    Many astronomers now participate in large international collaborations, and it is important to examine whether these structures foster a scientific climate that is inclusive and diverse. The Committee on the Participation of Women in the Sloan Digital Sky Survey (CPWS) was formed to evaluate the demographics and gender climate within SDSS-IV, one of the largest and most geographically distributed astronomical collaborations. In April 2014, the CPWS administered a demographic survey to establish a baseline for the incipient SDSS-IV. We received responses from 250 participants (46% of the active membership). Half of the survey respondents were located in the US or Canada and 30% were based in Europe. Eleven percent of survey respondents considered themselves to be an ethnic minority at their current institution. Twenty-five percent of the SDSS-IV collaboration members are women, a fraction that is consistent with the US astronomical community, but substantially higher than the fraction of women in the IAU (16%)...

  20. The impact of extrinsic demographic factors on Cantonese speech acquisition.

    PubMed

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

    2013-05-01

    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, presence of siblings and having a domestic helper as the main caregiver was collected via parent questionnaires. After controlling for age and sex, higher maternal education and higher household income were significantly associated with better speech skills; however, these variables explained a negligible amount of variance. Paternal education, number of siblings and having a foreign domestic helper did not associate with a child's speech acquisition. Extrinsic factors only exerted minimal influence on children's speech acquisition. A large amount of unexplained variance in speech ability still warrants further research. PMID:23635334

  1. Joint custody: solution or illusion?

    PubMed

    Benedek, E P; Benedek, R S

    1979-12-01

    Although the phrase "joint custody" is in popular use, the concept lacks standard definitin; parents who express interest in this form of disposition have widely differing objectives and expectations. The authors discuss the need for determining the primary objectives of the parties involved and for exploring the potential for achieving these through joint custody as well as through other alternatives. They examine the benefits of joint custody as well as the risks engendered by this type of arrangement and make a number of specific recommendations. They conclude that joint custody should be considered and explored, together with other available alternatives, and awarded only in appropriate cases. PMID:507203

  2. Biofluid lubrication for artificial joints 

    E-print Network

    Pendelton, Alice Mae

    2009-05-15

    This research investigated biofluid lubrication related to artificial joints using tribological and rheological approaches. Biofluids studied here represent two categories of fluids, base fluids and nanostructured biofluids. ...

  3. Metacarpophalangeal joint arthroscopy: indications revisited.

    PubMed

    Choi, Alexander K Y; Chow, Esther C S; Ho, P C; Chow, Y Y

    2011-08-01

    Arthroscopic surgery has become the gold standard for the diagnosis and treatment of major joint disorders. With advancement in arthroscopic technique, arthroscopy has become feasible in most human joints, even those as small as the finger joints. The metacarpophalangeal joint (MCPJ) can become spacious with simple traction, the intra-articular anatomy is simple, and its major structures can be easily visualized and identified. However, MCPJ arthroscopy has never been popular. This article describes our experience with MCPJ arthroscopy and seeks to establish its role in clinical practice. PMID:21871361

  4. Rotary Joint for Heat Transfer

    NASA Technical Reports Server (NTRS)

    Shauback, R.

    1986-01-01

    Rotary joint exchanges heat between two heat pipes - one rotating and one stationary. Joint accommodates varying heat loads with little temperature drop across interface. According to concept, heat pipe enters center of disklike stationary section of joint. There, wicks in central artery of heat pipe separate into multiple strands that lead to concentric channels on rotaryinterface side of stationary disk. Thin layer of liquid sodium/potassium alloy carries heat from one member of rotary joint to other. Liquid conducts heat efficiently while permitting relative motion between members. Polypropylene rings contain liquid without interfering with rotation.

  5. Who Falls for Phish? A Demographic Analysis of Phishing Susceptibility and Effectiveness of Interventions

    E-print Network

    Cranor, Lorrie Faith

    Who Falls for Phish? A Demographic Analysis of Phishing Susceptibility and Effectiveness between demographics and phishing susceptibility and the effectiveness of several anti- phishing educational materials. Our results suggest that women are more susceptible than men to phishing

  6. Demographic structure and capital accumulation: A quantitative assessment

    Microsoft Academic Search

    Sau-Him Paul Lau

    2009-01-01

    In a recent paper, d’Albis [2007. Demographic structure and capital accumulation. Journal of Economic Theory 132, 411–434] shows that the effect of population growth on capital accumulation is ambiguous in overlapping-generations models with age-specific mortality rates, contrasting to the predicted negative effect in Diamond [1965. National debt in a neoclassical growth model. American Economic Review 55, 1126–1150] and Blanchard [1985.

  7. Demographic Variability in Monkeys: Implications for Theory and Conservation

    Microsoft Academic Search

    Thomas T. Struhsaker

    2008-01-01

    Demographic parameters of nonhuman primates, like those of all other organisms, vary over time and space. However, many contemporary\\u000a models comparing multiple species treat these parameters as if they were static. Population density, group size, age-sex composition,\\u000a natality, and juvenile recruitment all vary considerably within populations that researchers have studied for many years.\\u000a It is important to describe and to

  8. A social and demographic study of Tibetan refugees in India

    Microsoft Academic Search

    Shushum Bhatia; Tsegyal Dranyi; Derrick Rowley

    2002-01-01

    The social and demographic characteristics of ?65,000 Tibetan refugees in India were determined from data collected 1994–1996. Approximately 55,000 refugees were living in 37 settlements widely distributed around India. The remaining 10,000 refugees were monks living in monasteries associated with some of the settlements, mostly in the south of India. In the settlements, a community-based surveillance system was established and

  9. “Hooking Up” Among College Students: Demographic and Psychosocial Correlates

    Microsoft Academic Search

    Jesse J. Owen; Galena K. Rhoades; Scott M. Stanley; Frank D. Fincham

    2010-01-01

    This study investigated 832 college students’ experiences with hooking up, a term that refers to a range of physically intimate\\u000a behavior (e.g., passionate kissing, oral sex, and intercourse) that occurs outside of a committed relationship. Specifically,\\u000a we examined how five demographic variables (sex, ethnicity, parental income, parental divorce, and religiosity) and six psychosocial\\u000a factors (e.g., attachment styles, alcohol use, psychological

  10. A study of the demographic characteristics of domestic tourists.

    PubMed

    Wu, B; Liu, X; Zhao, R

    1996-01-01

    "A sample survey was conducted [in China]: more than 6,000 questionnaires were submitted and retrieved from domestic tourists in Shanghai, Xi'ian, Huangshan, and Huashan in order to provide data for demographic analysis of the special fluid population of tourists. The paper looks at the relationship between tourists' gender, age, income, occupation, education, and family structure, as well as their tourist activity, selection of destinations, shopping, and other tourist behaviors." PMID:12292597

  11. [The demographic aspect and its integration into socioeconomic planning].

    PubMed

    Meza, M; Gomez, G; Suazo, M

    1980-01-01

    In order to achieve a deeper understanding of the interrelationships between population and economic and social variables for planning purposes, a computer simulation model of the Honduran economy incorporating demographic, economic, and social features was developed from 1977-79. The final model was adapted to the available data and human and technical resources. It consists of 3 parts: demographic aspects, economy and government, and social services, each of which has subroutines or submodels. At present the model is in operational condition in an IBM 370 computer in the National Information Center. In meetings with planning personnel of different levels, the appropriateness of the categories employed by the model has been noted, as has the need for priority to certain studies, especially studies pertaining to internal migration and income distribution. The model is currently in the process of validation, for which studies have been done from 1961-74 for the integrated demographic submodel and for 1975-78 for the economy and government section and the education and health submodels. Comparative studies will begin when the validation process is completed. Among the 3 main sections of the model, the demographic part has 4 subroutines covering mortality, family planning, fertility, and international migration; the economy and government part has 3 submodels covering governmental budget, government actions, and the economy; and the social services part has 1 submodel for education and 1 submodel for health, which has a further 7 subroutines concerning resources, environmental sanitation, health care, preventive medicine, maternal and child health, dental attention, and general morbidity. PMID:12265326

  12. Jointly Sponsored Research Program

    SciTech Connect

    Everett A. Sondreal; John G. Hendrikson; Thomas A. Erickson

    2009-03-31

    U.S. Department of Energy (DOE) Cooperative Agreement DE-FC26-98FT40321 funded through the Office of Fossil Energy and administered at the National Energy Technology Laboratory (NETL) supported the performance of a Jointly Sponsored Research Program (JSRP) at the Energy & Environmental Research Center (EERC) with a minimum 50% nonfederal cost share to assist industry in commercializing and effectively applying highly efficient, nonpolluting energy systems that meet the nation's requirements for clean fuels, chemicals, and electricity in the 21st century. The EERC in partnership with its nonfederal partners jointly performed 131 JSRP projects for which the total DOE cost share was $22,716,634 (38%) and the nonfederal share was $36,776,573 (62%). Summaries of these projects are presented in this report for six program areas: (1) resource characterization and waste management, (2) air quality assessment and control, (3) advanced power systems, (4) advanced fuel forms, (5) value-added coproducts, and (6) advanced materials. The work performed under this agreement addressed DOE goals for reductions in CO{sub 2} emissions through efficiency, capture, and sequestration; near-zero emissions from highly efficient coal-fired power plants; environmental control capabilities for SO{sub 2}, NO{sub x}, fine respirable particulate (PM{sub 2.5}), and mercury; alternative transportation fuels including liquid synfuels and hydrogen; and synergistic integration of fossil and renewable resources.

  13. Glenohumeral Joint Injections

    PubMed Central

    Gross, Christopher; Dhawan, Aman; Harwood, Daniel; Gochanour, Eric; Romeo, Anthony

    2013-01-01

    Context: Intra-articular injections into the glenohumeral joint are commonly performed by musculoskeletal providers, including orthopaedic surgeons, family medicine physicians, rheumatologists, and physician assistants. Despite their frequent use, there is little guidance for injectable treatments to the glenohumeral joint for conditions such as osteoarthritis, adhesive capsulitis, and rheumatoid arthritis. Evidence Acquisition: We performed a comprehensive review of the available literature on glenohumeral injections to help clarify the current evidence-based practice and identify deficits in our understanding. We searched MEDLINE (1948 to December 2011 [week 1]) and EMBASE (1980 to 2011 [week 49]) using various permutations of intra-articular injections AND (corticosteroid OR hyaluronic acid) and (adhesive capsulitis OR arthritis). Results: We identified 1 and 7 studies that investigated intra-articular corticosteroid injections for the treatment of osteoarthritis and adhesive capsulitis, respectively. Two and 3 studies investigated the use of hyaluronic acid in osteoarthritis and adhesive capsulitis, respectively. One study compared corticosteroids and hyaluronic acid injections in the treatment of osteoarthritis, and another discussed adhesive capsulitis. Conclusion: Based on existing studies and their level of evidence, there is only expert opinion to guide corticosteroid injection for osteoarthritis as well as hyaluronic acid injection for osteoarthritis and adhesive capsulitis. PMID:24427384

  14. Joint collaborative technology experiment

    NASA Astrophysics Data System (ADS)

    Wills, Michael; Ciccimaro, Donny; Yee, See; Denewiler, Thomas; Stroumtsos, Nicholas; Messamore, John; Brown, Rodney; Skibba, Brian; Clapp, Daniel; Wit, Jeff; Shirts, Randy J.; Dion, Gary N.; Anselmo, Gary S.

    2009-05-01

    Use of unmanned systems is rapidly growing within the military and civilian sectors in a variety of roles including reconnaissance, surveillance, explosive ordinance disposal (EOD), and force-protection and perimeter security. As utilization of these systems grows at an ever increasing rate, the need for unmanned systems teaming and inter-system collaboration becomes apparent. Collaboration provides a means of enhancing individual system capabilities through relevant data exchange that contributes to cooperative behaviors between systems and enables new capabilities not possible if the systems operate independently. A collaborative networked approach to development holds the promise of adding mission capability while simultaneously reducing the workload of system operators. The Joint Collaborative Technology Experiment (JCTE) joins individual technology development efforts within the Air Force, Navy, and Army to demonstrate the potential benefits of interoperable multiple system collaboration in a force-protection application. JCTE participants are the Air Force Research Laboratory, Materials and Manufacturing Directorate, Airbase Technologies Division, Force Protection Branch (AFRL/RXQF); the Army Aviation and Missile Research, Development, and Engineering Center Software Engineering Directorate (AMRDEC SED); and the Space and Naval Warfare Systems Center - Pacific (SSC Pacific) Unmanned Systems Branch operating with funding provided by the Joint Ground Robotics Enterprise (JGRE). This paper will describe the efforts to date in system development by the three partner organizations, development of collaborative behaviors and experimentation in the force-protection application, results and lessons learned at a technical demonstration, simulation results, and a path forward for future work.

  15. Profile: The Niakhar Health and Demographic Surveillance System

    PubMed Central

    Delaunay, Valerie; Douillot, Laetitia; Diallo, Aldiouma; Dione, Djibril; Trape, Jean-François; Medianikov, Oleg; Raoult, Didier; Sokhna, Cheikh

    2013-01-01

    The Health and Demographic Surveillance System (HDSS) in Niakhar, a rural area of Senegal, is located 135 km east of Dakar. The HDSS was established in 1962 by the Institut de Recherche pour le Développement (IRD) of Senegal to face the shortcomings of the civil registration system and provide demographic indicators. Some 65 villages in the Niakhar area were followed annually by the HDSS from 1962–1969. The study zone was reduced to 8 villages from 1969–1983, and from then on the HDSS was extended to include 22 other villages, covering a total of 30 villages for a population estimated at 43 000 in January 2012. Thus, 8 villages in the Niakhar area have been under demographic surveillance for almost 50 years and 30 villages for 30 years. Vital events, migrations, marital changes, pregnancies, and immunizations are routinely recorded every 4 months. The HDSS data base also includes epidemiological, economic, and environmental information obtained from specific surveys. Data were collected through annual rounds from 1962 to 1987. The rounds became weekly from 1987–1997, followed by routine visits conducted every 3 months between 1997 and 2007 and every 4 months since then. The data collected in the HDSS are not open to access, but can be fairly shared under conditions of collaboration and endowment. PMID:24062286

  16. Demographic stochasticity and evolution of dispersion I. Spatially homogeneous environments.

    PubMed

    Lin, Yen Ting; Kim, Hyejin; Doering, Charles R

    2015-02-01

    The selection of dispersion is a classical problem in ecology and evolutionary biology. Deterministic dynamical models of two competing species differing only in their passive dispersal rates suggest that the lower mobility species has a competitive advantage in inhomogeneous environments, and that dispersion is a neutral characteristic in homogeneous environments. Here we consider models including local population fluctuations due to both individual movements and random birth and death events to investigate the effect of demographic stochasticity on the competition between species with different dispersal rates. In this paper, the first of two, we focus on homogeneous environments where deterministic models predict degenerate dynamics in the sense that there are many (marginally) stable equilibria with the species' coexistence ratio depending only on initial data. When demographic stochasticity is included the situation changes. A novel large carrying capacity ([Formula: see text]) asymptotic analysis, confirmed by direct numerical simulations, shows that a preference for faster dispersers emerges on a precisely defined [Formula: see text] time scale. We conclude that while there is no evolutionarily stable rate for competitors to choose in these models, the selection mechanism quantified here is the essential counterbalance in spatially inhomogeneous models including demographic fluctuations which do display an evolutionarily stable dispersal rate. PMID:24682331

  17. Demographics of acute admissions to a National Spinal Injuries Unit

    PubMed Central

    Boran, S.; Street, J.; Higgins, T.; McCormack, D.; Poynton, A. R.

    2009-01-01

    This prospective demographic study was undertaken to review the epidemiology and demographics of all acute admissions to the National Spinal Injuries Unit in Ireland for the 5 years to 2003. The study was conducted at the National Spinal Injuries Unit, Mater Miscericordiae University Hospital, Dublin, Ireland. Records of all patients admitted to our unit from 1999 to 2003 were compiled from a prospective computerized spinal database. In this 5-year period, 942 patients were acutely hospitalized at the National Spinal Injuries Unit. There were 686 (73%) males and 256 (27%) females, with an average age of 32 years (range 16–84 years). The leading cause of admission with a spinal injury was road traffic accidents (42%), followed by falls (35%), sport (11%), neoplasia (7.5%) and miscellaneous (4.5%). The cervical spine was most commonly affected (51%), followed by lumbar (28%) and thoracic (21%). On admission 38% of patients were ASIA D or worse, of which one-third were AISA A. Understanding of the demographics of spinal column injuries in unique populations can help us to develop preventative and treatment strategies at both national and international levels. PMID:19283414

  18. Depression, Anxiety, Stress and Demographic Determinants of Hypertension Disease

    PubMed Central

    Mushtaq, Mamoona; Najam, Najma

    2014-01-01

    Background and Objective : Research evidence supports the relationship of psychological and demographic factors with hypertension and these variables are strongest predictors of hypertension which are scarcely studied in Pakistan. The present study was carried out to explore the correlation of depression, anxiety, stress and demographic factors with hypertension. Method: We used correlation research design and a sample of (N = 237), hypertensive patients (N = 137) and their age matched healthy controls (N = 100) was taken from hospitals. Depression, Anxiety and Stress Scale (DASS) (Lovibond & Lovibond, 1995) was used to assess depression, anxiety and stress. Results: Results indicated significant positive correlation between depression (?2MH = 104.18, p < .001), anxiety (?2MH = 78.48, p < .001), stress (?2MH = 110.95, p < .001) and overall negative states (?2MH = 97.43, p < .001) with hypertension. Depression (OR = 1.44, p < .01), anxiety (OR = 1. 76, p < .01) stress (OR = 1.37, p < .01), job and dependents, working hours and weight turned out as predictors of hypertension. Conclusion: Hypertension has significant positive relationship with depression, anxiety, stress and with demographic variables. The findings of the present study will contribute in the existing knowledge of health professionals to enhance public awareness regarding the harmful outcomes of depression, anxiety and stress upon human health. PMID:25674126

  19. On the Statistical Dependency of Identity Theft on Demographics

    NASA Astrophysics Data System (ADS)

    di Crescenzo, Giovanni

    An improved understanding of the identity theft problem is widely agreed to be necessary to succeed in counter-theft efforts in legislative, financial and research institutions. In this paper we report on a statistical study about the existence of relationships between identity theft and area demographics in the US. The identity theft data chosen was the number of citizen complaints to the Federal Trade Commission in a large number of US municipalities. The list of demographics used for any such municipality included: estimated population, median resident age, estimated median household income, percentage of citizens with a high school or higher degree, percentage of unemployed residents, percentage of married residents, percentage of foreign born residents, percentage of residents living in poverty, density of law enforcement employees, crime index, and political orientation according to the 2004 presidential election. Our study findings, based on linear regression techniques, include statistically significant relationships between the number of identity theft complaints and a non-trivial subset of these demographics.

  20. Demographic and clinical features of neuromyelitis optica: A review

    PubMed Central

    Asgari, N; Apiwattanakul, M; Palace, J; Paul, F; Leite, MI; Kleiter, I; Chitnis, T

    2015-01-01

    The comparative clinical and demographic features of neuromyelitis optica (NMO) are not well known. In this review we analyzed peer-reviewed publications for incidence and prevalence, clinical phenotypes, and demographic features of NMO. Population-based studies from Europe, South East and Southern Asia, the Caribbean, and Cuba suggest that the incidence and prevalence of NMO ranges from 0.05–0.4 and 0.52–4.4 per 100,000, respectively. Mean age at onset (32.6–45.7) and median time to first relapse (8–12 months) was similar. Most studies reported an excess of disease in women and a relapsing course, particularly in anti-aquaporin 4 antibody (anti AQP4-IgG)-positive patients. Ethnicity may have a bearing on disease phenotype and clinical outcome. Despite limitations inherent to the review process, themes noted in clinical and demographic features of NMO among different populations promote a more global understanding of NMO and strategies to address it. PMID:25921037

  1. Socio-demographic determinants of participation in mammography screening.

    PubMed

    von Euler-Chelpin, My; Olsen, Anne Helene; Njor, Sisse; Vejborg, Ilse; Schwartz, Walter; Lynge, Elsebeth

    2008-01-15

    Our objective was to use individual data on socio-demographic characteristics to identify predictors of participation in mammography screening and control to what extent they can explain the regional difference. We used data from mammography screening programmes in Copenhagen, 1991-1999, and Funen, 1993-2001, Denmark. Target groups were identified from the Population Register, screening data came from the health authority, and socio-demographic data from Statistics Denmark. Included were women eligible for at least 3 screens. The crude RR of never use versus always use was 3.21 (95%CI, 3.07-3.35) for Copenhagen versus Funen, and the adjusted RR was 2.55 (95%CI, 2.43-2.67). The adjusted RR for never use among women without contact to a primary care physician was 2.50 (95% CI, 2.31-2.71) and 2.89 (95% CI, 2.66-3.14), and for women without dental care 2.94 (95% CI, 2.77-3.12) and 2.88 (95% CI, 2.68-3.10) for Copenhagen and Funen, respectively. Other important predictive factors for nonparticipation were not being married and not being Danish. In conclusion, to enhance participation in mammography screening programmes special attention needs to be given to women not using other primary health care services. All women in Copenhagen, irrespective of their socio-demographic characteristics, had low participation. Screening programmes have to find ways to handle this urbanity factor. PMID:17893881

  2. Demographic and clinical profile of patients with brain metastases: A retrospective study

    PubMed Central

    Saha, Animesh; Ghosh, Sajal Kumar; Roy, Chhaya; Choudhury, Krishnangshu Bhanja; Chakrabarty, Bikramjit; Sarkar, Ratan

    2013-01-01

    Context: Brain metastases are the most common type of intracranial neoplasm, with the total number outnumbering primary brain tumors by a ratio of 10:1 and occur in about 25% of cancer patients. However, controversies exist regarding demographic and clinical profile of brain metastases. Aims: The purpose of this study was to analyze retrospectively the demographic and clinical profile of patients with brain metastases. Settings and Design: Retrospective, single institutional study. Materials and Methods: A retrospective study of 72 patients with brain metastasis was carried out from November 2010 to October 2012. The data pertaining to these patients was entered in a standardized case record form. These include History; clinical examination and other investigations including computed tomography/magnetic resonance imaging scan of the brain. Statistical Analysis: A statistical analysis was performed on the data collected using the MedCalc version 11. Results: Brain metastases were more common in male and occur in 6th decade of life mostly. There was no relationship of occupation or socio-economic status with the incidence of brain metastases. Carcinoma lung was the most common primary giving rise to brain metastases followed by breast. Adenocarcinoma accounts for most common histology of the primary that give rise to metastases. Multiple metastases were more common than the single group. Supratentorial lesions were more common than infratentorial lesions. Among them, parietal lobe was the most common site of involvement. Conclusions: The present study highlights that the incidence of brain metastasis is common in elderly population and mostly due to primary lung. Adenocarcinoma was the most common histology of primary. Majority of lesions has been observed at parietal lobe. PMID:24403959

  3. Population and Demographic Structure of Ixodes scapularis Say in the Eastern United States

    PubMed Central

    Sakamoto, Joyce M.; Goddard, Jerome; Rasgon, Jason L.

    2014-01-01

    Introduction The most significant vector of tick-borne pathogens in the United States is Ixodes scapularis Say (the blacklegged tick). Previous studies have identified significant genetic, behavioral and morphological differences between northern vs. southern populations of this tick. Because tick-borne pathogens are dependent on their vectors for transmission, a baseline understanding of the vector population structure is crucial to determining the risks and epidemiology of pathogen transmission. Methods We investigated population genetic variation of I. scapularis populations in the eastern United States using a multilocus approach. We sequenced and analyzed the mitochondrial COI and 16S genes and three nuclear genes (serpin2, ixoderin B and lysozyme) from wild specimens. Results We identified a deep divergence (3–7%) in I. scapularis COI gene sequences from some southern specimens, suggesting we had sampled a different Ixodes species. Analysis of mitochondrial 16S rRNA sequences did not support this hypothesis and indicated that all specimens were I. scapularis. Phylogenetic analysis and analysis of molecular variance (AMOVA) supported significant differences between northern vs. southern populations. Demographic analysis suggested that northern populations had experienced a bottleneck/expansion event sometime in the past, possibly associated with Pleistocene glaciation events. Conclusions Similar to other studies, our data support the division of northern vs. southern I. scapularis genetic lineages, likely due to differences in the demographic histories between these geographic regions. The deep divergence identified in some COI gene sequences highlights a potential hazard of relying solely on COI for species identification (“barcoding”) and population genetics in this important vector arthropod. PMID:25025532

  4. History of Dietetics History of Science 153

    E-print Network

    Shapin, Steven

    History of Dietetics History of Science 153 Fall 2008 Steven Shapin From Antiquity into the 19th of medicine. Dietetics was not just about food and drink; it was about the proper management of your life: how of recommended behaviors, belonging both to medicine and to practical ethics, to the world of `is' and the world

  5. China’s New Demographic Reality: Learning from the 2010 Census1

    PubMed Central

    Cai, Yong

    2015-01-01

    The paper provides an examination of China’s 2010 census data to evaluate its quality and to assess China’s demographic situation. The demographic trends revealed by the new census data suggest that China has entered a new demographic era characterized by prolonged low fertility, elevated sex ratios, rapid aging, fast urbanization and major geographic redistribution. How China responses to these demographic challenges will have profound implications for its social and economic future. PMID:25620818

  6. The History Guide

    NSDL National Science Digital Library

    Created by Prof. Steven Kreis, The History Guide is aimed at secondary and undergraduate students in History courses, studying for the A.P. test, or considering majoring in History. The core of the site is a collection of full text lectures from three university courses on Ancient and Medieval, Intellectual, and Twentieth Century European History. Also included are A Student's Guide to the Study of History, nine syllabi from courses Kreis has taught, a sizable collection of annotated links, and Kreis' own intellectual autobiography, which is presented for students considering graduate school in history.

  7. Demographic Factors in Adult and Continuing Education. A Resource Guide for Teachers, Administrators, and Policymakers.

    ERIC Educational Resources Information Center

    Jelinek, James J.

    This resource book contains demographic data for the eight states of the Mountain Plains Adult Education Association. All information is current (1990-92) and comes from the national census and hundreds of research studies. Chapter I provides a demographic perspective of the nation, describes a holistic view of demographics, and discusses…

  8. California Latina/Latino Demographic Data Book. A Policy Research Program Report.

    ERIC Educational Resources Information Center

    Gey, Fredric C.; And Others

    This report presents demographic data on California's Latino population. Data sources include census reports from 1980 and 1990; the 1990 Annual Demographic File; the 1990 and 1988 Voter Supplements; and the 1988 Fertility, Birth Expectation, and Immigration Study. The report includes the following information: (1) general demographic statistics…

  9. A Monte Carlo demographic analysis of the silky shark (Carcharhinus falciformis)

    E-print Network

    168 A Monte Carlo demographic analysis of the silky shark (Carcharhinus falciformis): implications mortality have shown promise for States. Monte Carlo methods are used shark demographic analysis (Cortés that reflect pos poration of Monte Carlo simulation in sible longline gear selectivity for silky demographic

  10. ECOLOGY AND POPULATION BIOLOGY Natural History and Ecological Correlates of Fungus-Growing Ants

    E-print Network

    Oliveira, Paulo S.

    ECOLOGY AND POPULATION BIOLOGY Natural History and Ecological Correlates of Fungus-Growing Ants. OLIVEIRA4 Ann. Entomol. Soc. Am. 104(5): 901Đ908 (2011); DOI: 10.1603/AN11067 ABSTRACT Fungus-growing ants. Here, we compare nest size and structure, colony size and demographic composition, and worker size

  11. The History and Future of Low Vision Services in the United States

    ERIC Educational Resources Information Center

    Mogk, Lylas; Goodrich, Gregory

    2004-01-01

    This article discusses the history of low vision services in the United States. The field began to gain momentum as the term "low vision" was conceptualized and coined, and this momentum is rapidly increasing with changes in the demographics of visual impairment.

  12. Intimate Partner and Nonintimate Violence History Among Drug-Using, Incarcerated Men

    Microsoft Academic Search

    TK Logan; Robert Walker; Carl G. Leukefeld

    2001-01-01

    There has been limited research focused on examining intimate and nonintimate violence perpetration patterns among incarcerated men. The purpose of this applied research study was to examine demographic, family, mental health, drug use, and criminal justice history among three groups of drug-using, incarcerated men: (a) those who report no violence of any kind (n = 47), (b) those who report

  13. Correlated contemporary evolution of life history traits in New Zealand Chinook salmon, Oncorhynchus tshawytscha

    Microsoft Academic Search

    M T Kinnison; T P Quinn; M J Unwin

    2011-01-01

    Size at age and age at maturity are important life history traits, affecting individual fitness and population demography. In salmon and other organisms, size and growth rate are commonly considered cues for maturation and thus age at maturity may or may not evolve independently of these features. Recent concerns surrounding the potential phenotypic and demographic responses of populations facing anthropogenic

  14. Contributors to Suicidal Ideation among Bipolar Patients with and without a History of Suicide Attempts

    ERIC Educational Resources Information Center

    Allen, Michael H.; Chessick, Cheryl A.; Miklowitz, David J.; Goldberg, Joseph F.; Wisniewski, Stephen R.; Miyahara, Sachiko; Calabrese, Joseph R.; Marangell, Lauren; Bauer, Mark S.; Thomas, Marshall R.; Bowden, Charles L.; Sachs, Gary S.

    2005-01-01

    This study was designed to develop models for vulnerability to suicidal ideation in bipolar patients. Logistic regression models examined correlates of suicidal ideation in patients who had versus had not attempted suicide previously. Of 477 patients assessed, complete data on demographic, illness history, and personality variables were available…

  15. Phylogeography, population history and conservation genetics of jaguars (Panthera onca, Mammalia, Felidae)

    Microsoft Academic Search

    Eduardo Eizirik; Jae-Heup Kim; Marilyn Menotti-Raymond; Peter G. Crawshaw JR.; Stephen J. O'Brien; Warren E. Johnson

    2001-01-01

    The jaguar ( Panthera onca ), the largest felid in the American Continent, is currently threatened by habitat loss, fragmentation and human persecution. We have investigated the genetic diversity, population structure and demographic history of jaguars across their geographical range by analysing 715 base pairs of the mitochondrial DNA (mtDNA) control region and 29 microsatellite loci in ? ? ?

  16. Genetic reconstructions of invasion history.

    PubMed

    Cristescu, Melania E

    2015-05-01

    A diverse array of molecular markers and constantly evolving analytical approaches have been employed to reconstruct the invasion histories of the most notorious invasions. Detailed information on the source(s) of introduction, invasion route, type of vectors, number of independent introductions and pathways of secondary spread has been corroborated for a large number of biological invasions. In this review, I present the promises and limitations of current techniques while discussing future directions. Broad phylogeographic surveys of native and introduced populations have traced back invasion routes with surprising precision. These approaches often further clarify species boundaries and reveal complex patterns of genetic relationships with noninvasive relatives. Moreover, fine-scale analyses of population genetics or genomics allow deep inferences on the colonization dynamics across invaded ranges and can reveal the extent of gene flow among populations across various geographical scales, major demographic events such as genetic bottlenecks as well as other important evolutionary events such as hybridization with native taxa, inbreeding and selective sweeps. Genetic data have been often corroborated successfully with historical, geographical and ecological data to enable a comprehensive reconstruction of the invasion process. The advent of next-generation sequencing, along with the availability of extensive databases of repository sequences generated by barcoding projects opens the opportunity to broadly monitor biodiversity, to identify early invasions and to quantify failed invasions that would otherwise remain inconspicuous to the human eye. PMID:25703061

  17. Uplift and Erosion Histories of Continents From Inversion of Drainage Networks

    NASA Astrophysics Data System (ADS)

    Roberts, Gareth G.; White, Nicky

    2015-04-01

    The uplift history of the Earth's surface contains important information about mechanisms of uplift. The uplift histories of Africa and Australia, for example, contain clues about the temporal and spatial evolution of mantle convection. Constraining uplift histories on continental length-scales is usually difficult because measurements of uplift or denudation (e.g. thermochronometry) are limited by their spatial resolution. We show that shapes of longitudinal river profiles contain information that can be used to invert for continental uplift rate histories. To invert river profiles for a history of uplift we first calibrate an erosional model. We show how stream-power models can be calibrated by jointly inverting families of longitudinal river profiles in Africa. We jointly invert 720 river profiles from Africa and 320 rivers from Australia for smooth histories of Cenozoic uplift. Our results indicate that geodynamic predictions of mantle convection fail to accurately predict changing patterns of dynamic support.

  18. Janice Bryant Oral History

    E-print Network

    Bryant, Janice; Helmer, Lauren

    2010-12-29

    Oral history interview with Janice Bryant conducted by Lauren Helmer in Marion, Kansas, on December 29, 2010. In this interview, Janice Bryant, a former church secretary for Valley Methodist Church, discusses the history, organization, and programs...

  19. Active joints for microrobot limbs

    Microsoft Academic Search

    M. Elwenspoek; L. Smith; B. Hok

    1992-01-01

    In this contribution we propose an electrostatic actuator for active joints. The active joint consists of two plates, one of which is a bilayer and bent by the bimorph effect. The plates are clamped to each other at one edge. A voltage between the plates leads to a very large field at the clamp where the plates are in intimate

  20. Joint strength in RCS frames 

    E-print Network

    Kirby, Cynthia Dawn

    1998-01-01

    for the addition of a RC slab, cover plates, and band plates. Results indicated that the addition of a reinforced concrete slab compositely connected to the steel beams framing into a typical RCS joints as defined by the ASCE guidelines (1994), improved the joint...

  1. Robotic joint experiments under ultravacuum

    NASA Technical Reports Server (NTRS)

    Borrien, A.; Petitjean, L.

    1988-01-01

    First, various aspects of a robotic joint development program, including gearbox technology, electromechanical components, lubrication, and test results, are discussed. Secondly, a test prototype of the joint allowing simulation of robotic arm dynamic effects is presented. This prototype is tested under vacuum with different types of motors and sensors to characterize the functional parameters: angular position error, mechanical backlash, gearbox efficiency, and lifetime.

  2. International Joint Commission

    NSDL National Science Digital Library

    The International Joint Commission was created by Canada and the United States "because they recognized that each country is affected by the other's actions in lake and river systems along the border. The two countries cooperate to manage these waters wisely and to protect them for the benefit of today's citizens and future generations." Visitors to the site can read about great lakes water quality issues, great lakes exports, water levels, news releases, publications, view maps, and much more. One of the latest publications available on the site includes the proceeding from a workshop entitled Addressing Atmospheric Mercury: Science and Policy. This extensive site is well organized and written, giving anyone living near or interested in the great lakes a good source for timely and important information.

  3. Smart material joint band

    NASA Astrophysics Data System (ADS)

    Tucchio, Michael A.; Stoodt, Robert A.; Livsey, Robert A.

    1993-12-01

    The present invention relates to an improved connector for joining two tubular members together. The connector is formed by a plurality of longitudinally extending fingers extending from an end of one of the tubular members and at least one locking groove in the other of the tubular members for receiving the fingers. The connector further includes a circumferentially extending wire member which is received in a notch in a head portion of each of the plurality of fingers. The wire member is preferably formed from a shape memory alloy and has an original circumference less than the circumference of a circle formed by the notches in the head portions of the fingers. The connector includes apertures through which electric wires may be connected to the shape memory alloy ring member so as to cause the shape memory alloy ring member to return to its original shape and allow release of the joint connection.

  4. Smart material joint band

    NASA Astrophysics Data System (ADS)

    Tucchio, Michael A.; Stoodt, Robert A.; Livsey, Robert A.

    1994-11-01

    The present invention relates to an improved connector for joining two tubular members together. The connector is formed by a plurality of longitudinally extending fingers extending from an end of one of tubular members and at least one locking groove in the other of the tubular members for receiving the fingers. The connector further includes a circumferentially extending wire member which is received in a notch in a head portion of each of the plurality of fingers. The wire member is preferably formed from a shape memory alloy and has an original circumference less than the circumference of a circle formed by the notches in a head portions of the fingers. The connector includes apertures through which electric wires may be connected to the shape memory alloy ring member so as to cause the shape memory alloy ring member to return to its original shape and allow release of the joint connection.

  5. Method of forming a joint

    DOEpatents

    Butt, Darryl Paul; Cutler, Raymond Ashton; Rynders, Steven Walton; Carolan, Michael Francis

    2006-08-22

    A method of joining at least two sintered bodies to form a composite structure, including providing a first multicomponent metallic oxide having a perovskitic or fluorite crystal structure; providing a second sintered body including a second multicomponent metallic oxide having a crystal structure of the same type as the first; and providing at an interface a joint material containing at least one metal oxide containing at least one metal identically contained in at least one of the first and second multicomponent metallic oxides. The joint material is free of cations of Si, Ge, Sn, Pb, P and Te and has a melting point below the sintering temperatures of both sintered bodies. The joint material is heated to a temperature above the melting point of the metal oxide(s) and below the sintering temperatures of the sintered bodies to form the joint. Structures containing such joints are also disclosed.

  6. Brian Hamilton History Department

    E-print Network

    Wisconsin at Madison, University of

    1 Brian Hamilton History Department Fall 2012 William Cronon, advisor U.S. ENVIRONMENTAL HISTORY Classics, Overviews, and Historiographic Essays Cronon, William. Changes in the Land: Indians, Alfred. "The Past and Present of Environmental History," American Historical Review 100 (1995): 1177

  7. Boxing in History

    Microsoft Academic Search

    Martin Johnes; Matthew Taylor

    2011-01-01

    This issue of Sport in History is the product of a symposium entitled ‘Boxing, History and Culture: New Themes and Perspectives’ held in June 2010 at De Montfort University and organized by the International Centre for Sports History and Culture. The symposium was an attempt to highlight and reflect upon a notable increase in recent years in scholarly research on

  8. A History Worth Preserving

    Microsoft Academic Search

    Cynthia Kelly

    2008-01-01

    The Manhattan Project transformed the course of American and world history, science, politics and society. If we can read about this in books and watch History Channel documentaries, why do we need to preserve some of the properties of this enormous undertaking? The presentation, ``A History Worth Preserving,'' will address why some of the physical properties need to be preserved

  9. The Trouble with History.

    ERIC Educational Resources Information Center

    Myers, John

    1990-01-01

    Cites the problems associated with teaching history: (1) lack of consensus on what and how to teach; (2) the adult perspective from which it is taught; (3) the abstract nature of history content; and (4) the concept of time. Concludes that efforts to include adolescent knowledge, skills, and attitudes should be considered in the history program.…

  10. History of Physics.

    ERIC Educational Resources Information Center

    Moyer, Albert E.

    1985-01-01

    Discusses the history of American physics, indicating that much effort has been on the atomic bond and high-energy physics, to the detriment of other topics and areas. To offset this tendency, significant research is going on in the history of solid-state physics, with glimmerings in the history of physics education. (JN)

  11. Classifying Geographical History

    Microsoft Academic Search

    Alan R. H. Baker

    2007-01-01

    Although the term “historical geography” has been the subject of a sustained and critical debate, that of “geographical history” has not. Usage of the latter term has been variable and the epistemological status of geographical history has been ambiguous. An examination of the usage of the term “geographical history” during the past 100 years or so reveals both that it

  12. 12 CFR 347.107 - Joint ventures.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ...2010-01-01 2010-01-01 false Joint ventures. 347.107 Section 347.107...REGULATIONS AND STATEMENTS OF GENERAL POLICY INTERNATIONAL BANKING § 347.107 Joint ventures. (a) Joint ventures. If a bank, directly or...

  13. 29 CFR 791.2 - Joint employment.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ...2013-07-01 2013-07-01 false Joint employment. 791.2 Section 791...INTERPRETATION NOT DIRECTLY RELATED TO REGULATIONS JOINT EMPLOYMENT RELATIONSHIP UNDER FAIR LABOR STANDARDS ACT OF 1938 § 791.2 Joint employment. (a) A single...

  14. 29 CFR 791.2 - Joint employment.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ...2012-07-01 2012-07-01 false Joint employment. 791.2 Section 791...INTERPRETATION NOT DIRECTLY RELATED TO REGULATIONS JOINT EMPLOYMENT RELATIONSHIP UNDER FAIR LABOR STANDARDS ACT OF 1938 § 791.2 Joint employment. (a) A single...

  15. 29 CFR 791.2 - Joint employment.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ...2014-07-01 2014-07-01 false Joint employment. 791.2 Section 791...INTERPRETATION NOT DIRECTLY RELATED TO REGULATIONS JOINT EMPLOYMENT RELATIONSHIP UNDER FAIR LABOR STANDARDS ACT OF 1938 § 791.2 Joint employment. (a) A single...

  16. Development of cryogenic rotatable heat transfer joints

    NASA Astrophysics Data System (ADS)

    Sadunas, J. A.; Backovsky, Z. F.; Wilson, D. E.

    1992-07-01

    A summary of cryogenic rotatable heat transfer joint technology development, at Rockwell International Space Division, is presented. Starting with the flight qualified radiative joint on the RM-20B IR sensor of the early 70's, leading to rotatable heat pipe joint, gas conductive joints, rolling-contact-conductance joints, and the more recent work on development and evaluation of cryogenic rotatable seals and mechanical interfaces. Potential applications, joint design optimization, heat transfer, seal leakage and torque test data are presented.

  17. Documents in Military History

    NSDL National Science Digital Library

    Edited by Dave Stewart, assistant professor of history at Hillsdale College (Hillsdale, Michigan), Documents in Military History is an online collection of primary sources for military history. The collection emphasizes pre-twentieth-century European military history but also includes some documents that address American and non-Western histories. Currently, the collection contains 325 items in six major historical sections: Ancient, Medieval, Early Modern, French Revolution, Nineteenth Century, and Naval Warfare. Each major section is further divided into more specific subsections. The organized layout of the site promotes chronological browsing. The site also provides a keyword search facility (inoperable at the time of review).

  18. Food security and environmental degradation in northern Nigeria: demographic perspectives.

    PubMed

    Lockwood, M

    1991-07-01

    The Malthusian controversy about the causes of environmental change and food insecurity in Hausaland in northern Nigeria is examined. The argument is irresolvable based on available data at the macro level. The individual and household level are appropriate for answering the question about how high density populations survive on a savannah. To understand population pressure in Hausaland, it is important to read Malthus very carefully and to understand the existing demographic structure in which economic and kinship relations support high fertility even where land is scarce. Demographic responses vary with economic strata. Policies ignore individual level differences. Since 1953, the densely populated areas of Sokoto, Katsina, Zaria, and Kano have spread in an area that is largely dry with a moderate-to-high risk of desertification. Food insecurity exists not only in times of drought, but also annually in the form of chronic shortages of staples for poor farmers. Average land holdings/capita have become smaller. Population pressure has also contributed to shifts in land use. Food prices have increased. Possible explanations include 1) the drought and the oil boom have a greater impact on environmental change and food insecurity and rural Hausa farmers have responded by raising yields, managing tree resources, and practicing soil conservation and 2) an independent source of income from non-agricultural activities is an essential part of the economy. The relationship among population pressure, land shortage, and food insecurity is complex. It is inaccurate to label Hausa as subsistence farmers, when trading in grain is an important enterprise. The role that commercialization of agriculture plays in food insecurity is discussed. Malthusian disaster is not imminent. The proximate determinants of fertility, birth spacing practices and infertility, should lead to high fertility rates, but in this case they do not. Determinants responsive to economic factors tend to be contraception and marriage, which are both marginal in the north. The Hausa system is demographically unresponsive, but it is economically and social absorptive of population pressure. PMID:12344930

  19. India has done it: demographic transition already underway in India.

    PubMed

    Gowarikar, V

    1995-10-01

    The author posits that a classical demographic transition in India in underway. Birth and death rates are declining in both rural and urban areas of all states. Specifically, the following four stages were completed. 1) During 1941-71, the death rate declined sharply and the birth rate declined somewhat. 2) The natural growth rate increased dramatically from 8.7 to 22.2. 3) After 1971, the birth rate began to decline dramatically over a 10-year period and the natural growth rate stabilized at 22.2. 4) During 1981-91, the magnitude of the birth rate decline was greater than the death rate decline. The natural growth rate declined to 19.7. The final stage of transition is the current one. The natural growth rate is expected to decline at a faster rate until it reaches zero. The birth rate ranges from 18.1 in Kerala to 35.8 in Madhya Pradesh. It is expected in the final stage of India's demographic transition that the crude birth rate will decline to 21 in 2003 and the crude death rate will decline to 8. The natural growth rate under such a scenario would be 13. The estimation of the decline in the crude birth rate is based on present determinant factors, such as literacy, wealth generation, energy consumption, and food availability. Future strategies should continue with the improvement in the role of the Family Welfare Department and with continued strengthening of existing programs. The rise in population size should be understood as a natural historical demographic process and not a reason to dismantle and destabilize a program going back to 1951. Rajasthan and Haryana have legislation that bars people from holding office, if their family size is greater than two children. This action is commended. India has a need for government to demystify contraception as was accomplished in Thailand and to create awareness of modern methods and the potential for side effects without discouraging use. PMID:12291348

  20. THE PHOENIX POPULATION: DEMOGRAPHIC CRISIS AND REBOUND IN CAMBODIA*

    PubMed Central

    HEUVELINE, PATRICK; POCH, BUNNAK

    2014-01-01

    The study of mortality crises provides an unusual and valuable perspective on the relationship between mortality and fertility changes, a relationship that has puzzled demographers for decades. In this article, we combine nationally representative survey and demographic-surveillance system data to study fertility trends around the time of the Khmer Rouge (KR) regime, under which 25% of the Cambodian population died. We present the first quantitative evidence to date that attests to a one-third decline of fertility during this regime, followed by a substantial “baby boom” after the fall of the KR. Further analyses reveal that the fertility rebound was produced not only by a two-year marriage bubble but also by a surge in marital fertility that remained for nearly a decade above its precrisis level. Our results illustrate the potential influence of mortality on fertility, which may be more difficult to identify for more gradual mortality declines. To the extent that until recently, Cambodian fertility appears to fit natural fertility patterns, our findings also reinforce meaning of this core paradigm of demographic analysis. In July 1978, a youth named Korb, bound hand and foot, arrived at a Pol Pot regime extermination camp. The local security chief, “Comrade Uncle An,” was handed the following note: Formerly this person was normal in character. Then, over about ten days, he went crazy. […] If many people come in, first he begins to whistle, and then he sings the following rhyme out loud: O! Khmers with black blood Now the eight-year Buddhist prophecy is being fulfilled. Vietnam is the elder brother Kampuchea is the younger. If we do not follow the Vietnamese as our elder brothers There will be nothing left of the Khmer this time but ashes.(Kiernan and Boua 1982:363) PMID:17583312

  1. Comparing Demographic Characteristics of Male Victims of Domestic Violence

    NASA Astrophysics Data System (ADS)

    Pournaghash-Tehrani, Said; Feizabadi, Zahra

    The present study investigated the demographic characteristics of male victims of domestic violence. These demographic characteristics were menxs age, level of education and level of income. To do this, an author-made questionnaire regarding victimization of domestic violence, both, physical and psychological, was administered to 120 randomly chosen men, referred to family courts by their councilors to seek divorce because of experiencing domestic violence. The results showed that age had significant effect on physical violence; specifically, hitting and psychological violence; specifically, denying choices and cessation of intermarital intercourse. Also, the level of education had significant effect on the physical (e.g., throwing objects) and psychological (e.g., Cessation of marital intercourse and denying choices). Finally, present results indicated that the level of income, by itself, did not have any effects on experiencing any types of violence by men but its effect was visible and significant in the presence of the other two factors, the age and the level of education. The results in the present study are, in fact, only of their kinds in that the characteristics of abused men by their wives are assessed in male victims of domestic violence and can contribute to further understanding of the types of men susceptible to victimization by their wives. Furthermore, it should be pointed out that other demographic variables such as the number of children, the type of housing (ownership of the house or renting) and so on, were also determined in this study, but given their lack of any significant effects on the occurrence of violence of any kind against men, were not mentioned in the study.

  2. Genetic Diversity and Population History of a Critically Endangered Primate, the Northern Muriqui (Brachyteles hypoxanthus)

    PubMed Central

    de B. Possamai, Carla; Dias, Luiz G.; Boubli, Jean P.; Strier, Karen B.; Mendes, Sérgio L.; Fagundes, Valéria

    2011-01-01

    Social, ecological, and historical processes affect the genetic structure of primate populations, and therefore have key implications for the conservation of endangered species. The northern muriqui (Brachyteles hypoxanthus) is a critically endangered New World monkey and a flagship species for the conservation of the Atlantic Forest hotspot. Yet, like other neotropical primates, little is known about its population history and the genetic structure of remnant populations. We analyzed the mitochondrial DNA control region of 152 northern muriquis, or 17.6% of the 864 northern muriquis from 8 of the 12 known extant populations and found no evidence of phylogeographic partitions or past population shrinkage/expansion. Bayesian and classic analyses show that this finding may be attributed to the joint contribution of female-biased dispersal, demographic stability, and a relatively large historic population size. Past population stability is consistent with a central Atlantic Forest Pleistocene refuge. In addition, the best scenario supported by an Approximate Bayesian Computation analysis, significant fixation indices (?ST?=?0.49, ?CT?=?0.24), and population-specific haplotypes, coupled with the extirpation of intermediate populations, are indicative of a recent geographic structuring of genetic diversity during the Holocene. Genetic diversity is higher in populations living in larger areas (>2,000 hectares), but it is remarkably low in the species overall (??=?0.018). Three populations occurring in protected reserves and one fragmented population inhabiting private lands harbor 22 out of 23 haplotypes, most of which are population-exclusive, and therefore represent patchy repositories of the species' genetic diversity. We suggest that these populations be treated as discrete units for conservation management purposes. PMID:21694757

  3. Patient-interactive computer system for obtaining medication histories.

    PubMed

    DeLeo, J M; Pucino, F; Calis, K A; Crawford, K W; Dorworth, T; Gallelli, J F

    1993-11-01

    A portable, patient-interactive computerized system for obtaining medication histories is described. A comprehensive interview script modeling pharmacist-conducted medication-history interviews was written in lay language. The script contains sections on demographics, current medical conditions, medication regimen, medication compliance, symptoms, allergy history, dietary history, psychosocial history, and occupational and environmental exposure; it also asks the patient to evaluate the system. Some of the information requested is often not obtained by physicians during the history and physical examination. A program that conducts the interview by processing a computerized version of the script was developed with Microsoft QuickBASIC. The program was designed to be run on a personal computer microprocessor so that an interview can be conducted virtually anywhere by using a desktop or laptop computer. Summary reports suitable for inclusion in the medical record are generated after each interview. Patients using the system took an average of 40 minutes to complete an interview. They entered data easily and accurately, and they gave the system a high overall rating. The medication-history interviewing system described produces useful, comprehensive, and consistent reports and requires about the same amount of time to conduct an interview as a human interviewer. PMID:8266960

  4. KSC History Project

    NASA Technical Reports Server (NTRS)

    Moore, Patrick K.

    2002-01-01

    The 2002 NASA/ASEE KSC History Project focused on a series of seven history initiatives designed to acquire, preserve, and interpret the history of Kennedy Space Center. These seven projects included the co-authoring of Voices From the Cape, historical work with NASA historian Roger Launius, the completion of a series of oral histories with key KSC personnel, a monograph on Public Affairs, the development of a Historical Concept Map (CMap) for history knowledge preservation, advice on KSC history database and web interface capabilities, the development of a KSC oral history program and guidelines of training and collection, and the development of collaborative relationships between Kennedy Space Center, the University of West Florida, and the University of Central Florida.

  5. Joint numerical ranges, quantum maps, and joint numerical shadows

    E-print Network

    Eugene Gutkin; Karol Zyczkowski

    2012-10-12

    We associate with k hermitian N\\times N matrices a probability measure on R^k. It is supported on the joint numerical range of the k-tuple of matrices. We call this measure the joint numerical shadow of these matrices. Let k=2. A pair of hermitian N\\times N matrices defines a complex N\\times N matrix. The joint numerical range and the joint numerical shadow of the pair of hermitian matrices coincide with the numerical range and the numerical shadow, respectively, of this complex matrix. We study relationships between the dynamics of quantum maps on the set of quantum states, on one hand, and the numerical ranges, on the other hand. In particular, we show that under the identity resolution assumption on Kraus operators defining the quantum map, the dynamics shrinks numerical ranges.

  6. Models for jointed rock structures

    NASA Astrophysics Data System (ADS)

    Heuze, F. E.; Barbour, T. G.

    1981-03-01

    Models for axisymmetric interfaces found in shaft and footing designs, and for the dilatant effects of rock joints, as encountered in underground caverns and reinforced rock slopes are presented. The models were incorporated into a finite element program, and test case analyses were performed. Use of the models can lead to safer estimates of footing settlements and shaft lining stresses, as well as to more economical design of rock reinforcement. Because the dilatant joint provides a refined estimate of joint opening and closing, it can be applied to the analysis of hard rock hydraulics, in which the flow is very sensitive to fracture aperture.

  7. Determination of impact tensile properties of structural epoxy adhesive butt joints using a hat-shaped specimen

    NASA Astrophysics Data System (ADS)

    Yokoyama, T.; Nakai, K.

    2006-08-01

    The impact tensile properties of structural epoxy adhesive butt joints are determined with a modified version of the split Hopkinson pressure bar using a hat-shaped joint specimen. A typical two-component structural epoxy adhesive and two different adherend materials (Al alloy 7075-T6 and 99% pure titanium) are used in the adhesion tests. The impact joint tensile strength is evaluated from the applied tensile load history at failure. The corresponding static joint tensile strength is measured with an Instron testing machine using joint specimens of the same geometry as those used in the impact tests. It is demonstrated that the joint tensile strength increases definitely with increasing loading rate up to the order of 106 MPa/s, and decreases with increasing adhesive layer thickness up to nearly 180 ? m, depending on the adherend materials.

  8. Arthritis: joints inflamed.

    PubMed

    Casey, Georgina

    2015-06-01

    ARTHRITIS IS a generic term for inflammatory joint disease. There are various forms of arthritis, including osteoarthritis, rheumatoid arthritis and spondyloarthritis. Arthritis can be a chronic debilitating condition or a transient effect of bacterial or viral infections. As a chronic condition, arthritis can cause loss of quality of life, disability and, with rheumatoid disease, early death. The economic burden of arthritis, in terms of management and loss of productivity due to disability, is high and set to increase with the ageing population. Recent advances in our understanding of the causes and progression of a number of forms of arthritis have raised hopes of better management and possible remission. Pharmacotherapy has moved from symptom management to addressing underlying disease processes. However, therapies that prevent or cure arthritis remain elusive. Current care for people with arthritis relies on a multidisciplinary approach and substantial pharmacological intervention. Nurses have a key role to play in guiding patients through treatment, ensuring they receive optimal therapy to reduce the impact of arthritis and its management on their lives. PMID:26168559

  9. Acromioclavicular joint cyst formation.

    PubMed

    Hiller, Andrew D; Miller, Joshua D; Zeller, John L

    2010-03-01

    Acromioclavicular joint (ACJ) cysts are an uncommon and unusual sequela associated with shoulder pathophysiology. The majority of literature on ACJ cysts consists of individual case reports with no definitive literature review currently available. In addition to a comprehensive literature review, four clinical cases are presented in this report. First described by Craig (1984), a total of 41 cases have been previously reported in the literature. Of these cases, five occurred with the rotator cuff musculature intact. The remaining 36 cases of ACJ cysts occurred in patients with a complete tear/avulsion of the rotator cuff. Previous attempts at compiling a complete record of all reported cases have combined several distinct conditions into a single category. This article presents two distinct etiologies for the pathogenesis of ACJ cyst formation. In the presence of an intact rotator cuff, a Type 1 cyst can form superficially and be limited to the ACJ. Following a massive or traumatic tear of the rotator cuff, mechanical instability of the humeral head can cause a deterioration of the inferior acromioclavicular capsule (cuff tear arthropathy) and an overproduction of synovial fluid. Overtime, a "geyser" of fluid can form between the glenohumeral and the ACJ, forming a Type 2 cyst. This differentiation and categorization is essential for appropriate classification and treatment. PMID:20069645

  10. Joint services electronics program

    NASA Astrophysics Data System (ADS)

    Peters, Leon, Jr.

    1992-11-01

    The report represents the fifteenth annual summary of The Ohio State University Joint Services Electronics Program (JSEP). The transfer of the compact range identification technology initiated under JSEP support for time domain studies continues to make large advances. We are also assisting Rockwell (Tulsa) to update their RCS facilities. This work is on a subcontract to the ESL from the Air Force. This has lead to involvement in the study of Ultra Wide Band radar systems. The research activities devoted to the Generalized Ray and Gaussian Beams continues. Our JSEP research continues to be expanded by external funding. This program is being expanded by use of such funds which are more focussed on the requirements of the sponsors which includes both the Air Force and the Navy. Our JSEP research continues to focus on electromagnetic related topics. There are four major electromagnetics areas that were pursued in the past year. The Diffraction Studies Work Unit has initiated research on a time domain version of the Uniform Theory of Diffraction. A second topic under the Diffraction Studies Work Unit involves further extensions of the generalized resistive boundary condition and the generalized impedance boundary condition. These have been applied to scattering from a chiral slab. A third topic of interest is the diffraction from a corner. A fourth task involves the reflection/diffraction of a Gaussian beam. This represents an approach to replace the usual ray optics solution for very complex geometries where the versatile ray optics solution becomes cumbersome.

  11. Demographics of the Canadian dairy industry from 1991 to 2011.

    PubMed

    Jelinski, Murray D; LeBlanc, Stephen; Kennedy, Richard

    2015-07-01

    A retrospective study of the demographics of the Canadian dairy industry was conducted using data derived from Statistics Canada's Census of Agriculture from 1991 to 2011. This longitudinal study shows that Canada's dairy industry has undergone considerable consolidation. From 1991 to 2011, the number of dairy producers and dairy farms decreased by 48.9% and 61.9%, respectively. Furthermore, this trend in consolidation is likely to continue; nearly half (45.8%) of all dairy producers in Canada were ? 50 y of age in 2011. Not only will most of these producers be retired by 2021, but younger producers will also exit the industry for other reasons. These findings mirror what is occurring in Canada's cow-calf industry, underscoring that supply-managed sectors experience demographic consolidation similar to non-supply managed sectors. These substantial changes will have ramifications for the veterinary profession. There will be fewer but larger farms, and the services and knowledge demanded of veterinarians will change accordingly, which has implications for food animal veterinary education. PMID:26130831

  12. Managing diversity: Changing demographics in the engineering workplace

    SciTech Connect

    Judd, J.C.; Vella, J.J.

    1990-01-01

    Technological development creates a need for better educated workers with increased basic, analytical, and interpersonal skills. At the same time, both the population of 22-yr olds and the numbers of traditional students who are choosing careers in engineering and science are decreasing, creating a gap between engineering and construction needs and available trained resources. If more and better caliber students are not attracted to engineering, industry is expected to face selective shortages in the future. There is no question that the demographic composition of the next generation of engineers will significantly differ from that of today's engineers. Industry must recognize the changes that are occurring and take action to ensure that there continues to be an adequate supply of technically qualified workers in light of these demographic changes. In its role as adviser and coordinator of industry action, ANS can play a vital role in ensuring that the industry actions are timely and effective. The ANS should form a committee to study the changing composition of future engineers and constructors and formulate an effective action plan that industry can use to continue to attract able, top-performing students to the engineering field.

  13. Demographic data of thyroiditis from a south Indian city

    PubMed Central

    Kalra, Pramila; Kumar, K. M. Prasanna; Kallur, K. G.; Vadyanathan, Vidya; Nadig, Murali; Shankar, Mythri

    2015-01-01

    Background: Thyroiditis involves thyroid gland inflammation due to a wide variety of causes. The common varieties are subacute, silent and postpartum thyroiditis. Aims and Objectives: To retrospectively collect demographic data of thyroiditis from Bangalore over the past 5 years. Materials and Methods: Data were collected from three major nuclear medicine centers in Bangalore of the patients who came for technetium (Tc) 99m pertechnetate scan of the thyroid. The diagnosis was based on the Tc 99 scan evidence of thyroiditis in these patients and biochemical evidence of thyrotoxicosis. Results: The total number of cases recorded were 2513. The females were more commonly affected compared with males with sex distribution of 1698 females and 815 females (2:1). The mean age of females was 32.5 ± 11.3 years whereas the mean age of males was 37.2 ± 12.4 years. The highest numbers of cases were recorded in the months of June and August. Conclusions: The females developed thyroiditis frequently and at an earlier age when compared with males. This data could give us an insight into the demographic pattern of thyroiditis in our country and may help in planning future preventive strategies. PMID:25729697

  14. Overcoming Allee effects through evolutionary, genetic, and demographic rescue.

    PubMed

    Kanarek, Andrew R; Webb, Colleen T; Barfield, Michael; Holt, Robert D

    2015-01-01

    Despite the amplified threats of extinction facing small founder populations, successful colonization sometimes occurs, bringing devastating ecological and economic consequences. One explanation may be rapid evolution, which can increase mean fitness in populations declining towards extinction, permitting persistence and subsequent expansion. Such evolutionary rescue may be particularly important, given Allee effects. When a population is introduced at low density, individuals often experience a reduction in one or more components of fitness due to novel selection pressures that arise from diminished intraspecific interactions and positive density dependence (i.e. component Allee effects). A population can avoid extinction if it can adapt and recover on its own (i.e. evolutionary rescue), or if additional immigration sustains the population (i.e. demographic rescue) or boosts its genetic variation that facilitates adaptation (i.e. genetic rescue). These various forms of rescue have often been invoked as possible mechanisms for specific invasions, but their relative importance to invasion is not generally understood. Within a spatially explicit modelling framework, we consider the relative impact of each type of rescue on the probability of successful colonization, when there is evolution of a multi-locus quantitative trait that influences the strength of component Allee effects. We demonstrate that when Allee effects are important, the effect of demographic rescue via recurrent immigration overall provides the greatest opportunity for success. While highlighting the role of evolution in the invasion process, we underscore the importance of the ecological context influencing the persistence of small founder populations. PMID:25421449

  15. Epidemiology, demographic characteristics and prognostic predictors of ulcerative colitis

    PubMed Central

    da Silva, Bruno César; Lyra, Andre Castro; Rocha, Raquel; Santana, Genoile Oliveira

    2014-01-01

    Ulcerative colitis (UC) is a chronic disease characterized by diffuse inflammation of the mucosa of the colon and rectum. The hallmark clinical symptom of UC is bloody diarrhea. The clinical course is marked by exacerbations and remissions, which may occur spontaneously or in response to treatment changes or intercurrent illnesses. UC is most commonly diagnosed in late adolescence or early adulthood, but it can occur at any age. The incidence of UC has increased worldwide over recent decades, especially in developing nations. In contrast, during this period, therapeutic advances have improved the life expectancy of patients, and there has been a decrease in the mortality rate over time. It is important to emphasize that there is considerable variability in the phenotypic presentation of UC. Within this context, certain clinical and demographic characteristics are useful in identifying patients who tend to have more severe evolution of the disease and a poor prognosis. In this group of patients, better clinical surveillance and more intensive therapy may change the natural course of the disease. The aim of this article was to review the epidemiology and demographic characteristics of UC and the factors that may be associated with its clinical prognosis. PMID:25071340

  16. Profile: The Karonga Health and Demographic Surveillance System

    PubMed Central

    Crampin, Amelia C; Dube, Albert; Mboma, Sebastian; Price, Alison; Chihana, Menard; Jahn, Andreas; Baschieri, Angela; Molesworth, Anna; Mwaiyeghele, Elnaeus; Branson, Keith; Floyd, Sian; McGrath, Nuala; Fine, Paul E M; French, Neil; Glynn, Judith R; Zaba, Basia

    2012-01-01

    The Karonga Health and Demographic Surveillance System (Karonga HDSS) in northern Malawi currently has a population of more than 35?000 individuals under continuous demographic surveillance since completion of a baseline census (2002–2004). The surveillance system collects data on vital events and migration for individuals and for households. It also provides data on cause-specific mortality obtained by verbal autopsy for all age groups, and estimates rates of disease for specific presentations via linkage to clinical facility data. The Karonga HDSS provides a structure for surveys of socio-economic status, HIV sero-prevalence and incidence, sexual behaviour, fertility intentions and a sampling frame for other studies, as well as evaluating the impact of interventions, such as antiretroviral therapy and vaccination programmes. Uniquely, it relies on a network of village informants to report vital events and household moves, and furthermore is linked to an archive of biological samples and data from population surveys and other studies dating back three decades. PMID:22729235

  17. Evacuee Compliance Behavior Analysis using High Resolution Demographic Information

    SciTech Connect

    Lu, Wei [ORNL] [ORNL; Han, Lee [University of Tennessee, Knoxville (UTK)] [University of Tennessee, Knoxville (UTK); Liu, Cheng [ORNL] [ORNL; Tuttle, Mark A [ORNL] [ORNL; Bhaduri, Budhendra L [ORNL] [ORNL

    2014-01-01

    The purpose of this study is to examine whether evacuee compliance behavior with route assignments from different resolutions of demographic data would impact the evacuation performance. Most existing evacuation strategies assume that travelers will follow evacuation instructions, while in reality a certain percent of evacuees do not comply with prescribed instructions. In this paper, a comparison study of evacuation assignment based on Traffic Analysis Zones (TAZ) and high resolution LandScan USA Population Cells (LPC) were conducted for the detailed road network representing Alexandria, Virginia. A revised platform for evacuation modeling built on high resolution demographic data and activity-based microscopic traffic simulation is proposed. The results indicate that evacuee compliance behavior affects evacuation efficiency with traditional TAZ assignment, but it does not significantly compromise the efficiency with high resolution LPC assignment. The TAZ assignment also underestimates the real travel time during evacuation, especially for high compliance simulations. This suggests that conventional evacuation studies based on TAZ assignment might not be effective at providing efficient guidance to evacuees. From the high resolution data perspective, traveler compliance behavior is an important factor but it does not impact the system performance significantly. The highlight of evacuee compliance behavior analysis should be emphasized on individual evacuee level route/shelter assignments, rather than the whole system performance.

  18. Race differences in changing family demographics in the 1980s.

    PubMed

    Heaton, T B; Jacobson, C K

    1994-06-01

    Many social forces influence Black and White family demographics, with patterns of family formation varying greatly between the races. The authors explore the degree to which a common set of independent variables can account for differences in the timing of family formation and dissolution for Black and White families. Racial differences are specifically considered in the timing of initiation of sexual activity, first marriage, first birth, and divorce. Independent variables considered are adolescent living arrangements with either one or two parents, mother's educational level, religion, region of the country, area of residency, birth cohort, and year of the survey. Data are drawn from the third and fourth cycles of the National Survey of Family Growth, a national probability sample of women aged 14-45 years including 5778 Blacks and 9004 Whites. Estimates of how Blacks would differ if they had mean values on covariates equal to White observed means suggest that these independent variables inadequately explain differences between Black and White family formation and dissolution. The authors therefore conclude that Blacks and Whites may be responding to different structural and cultural constraints which are not easily captured by basic demographic variables. PMID:12318758

  19. The people yet to come; avoiding the demographic trap.

    PubMed

    Brown, L R

    1987-01-01

    The demographic trap is defined as the condition where a nation has passed through the process of lowering death rates, but has not been able to lower birth rates before ecological carrying capacity is exceeded. A minimal estimate predicts that by the year 2000, 63 countries, or 1.1 billion people, will be trapped by starvation, dependence on imported food, and resulting economic and political instability. Such a country that failed to complete the demographic transition will fall back to the original stage, of high death as well as birth rates. Most nations in Southeast Asia, Latin America, and Africa are at risk, notably Mexico, India, Nigeria, Ethiopia, because they already have falling living standards coupled with rapid growth rates. Most governments are unaware of the subtle signs that carrying capacity has been exceeded. Even those that are able to understand such events, often practice ineffective policies. For example, the U.S. has dropped U.N.F.P.A. support ostensibly because one nation, China, allowed forced abortions. On the other hand, some third world countries have initiated novel campaigns to reduce births, for example popular media campaigns in Mexico, free dissemination of birth control pills to all women in Brazil, and a separate family planning ministry in Zimbabwe. PMID:12341670

  20. Socio-Demographics and the Development of Malaria Elimination Strategies in the Low Transmission Setting

    PubMed Central

    Chuquiyauri, Raul; Paredes, Maribel; Peńataro, Pablo; Torres, Sonia; Marin, Silvia; Tenorio, Alexander; Brouwer, Kimberly C.; Abeles, Shira; Llanos-Cuentas, Alejandro; Gilman, Robert H.; Kosek, Margaret; Vinetz, Joseph M.

    2011-01-01

    This analysis presents a comprehensive description of malaria burden and risk factors in Peruvian Amazon villages where malaria transmission is hypoendemic. More than 9,000 subjects were studied in contrasting village settings within the Department of Loreto, Peru, where most malaria occurs in the country. Plasmodium vivax is responsible for more than 75% of malaria cases; severe disease from any form of malaria is uncommon and death rare. The association between lifetime malaria episodes and individual and household covariates was studied using polychotomous logistic regression analysis, assessing effects on odds of some vs. no lifetime malaria episodes. Malaria morbidity during lifetime was strongly associated with age, logging, farming, travel history, and living with a logger or agriculturist. Select groups of adults, particularly loggers and agriculturists acquire multiple malaria infections in transmission settings outside of the main domicile, and may be mobile human reservoirs by which malaria parasites move within and between micro-regions within malaria endemic settings. For example, such individuals might well be reservoirs of transmission by introducing or reintroducing malaria into their home villages and their own households, depending on vector ecology and the local village setting. Therefore, socio-demographic studies can identify people with the epidemiological characteristic of transmission risk, and these individuals would be prime targets against which to deploy transmission blocking strategies along with insecticide treated bednets and chemoprophylaxis. PMID:22100446