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1

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

E-print Network

Inferring the Joint Demographic History of Multiple Populations from Multidimensional SNP Frequency Demographic History of Multiple Populations from Multidimensional SNP Frequency Data. PLoS Genet 5(10): e

Sorenson, Michael

2

Demographic history and gene flow during silkworm domestication  

PubMed Central

Background Gene flow plays an important role in domestication history of domesticated species. However, little is known about the demographic history of domesticated silkworm involving gene flow with its wild relative. Results In this study, four model-based evolutionary scenarios to describe the demographic history of B. mori were hypothesized. Using Approximate Bayesian Computation method and DNA sequence data from 29 nuclear loci, we found that the gene flow at bottleneck model is the most likely scenario for silkworm domestication. The starting time of silkworm domestication was estimated to be approximate 7,500 years ago; the time of domestication termination was 3,984 years ago. Using coalescent simulation analysis, we also found that bi-directional gene flow occurred during silkworm domestication. Conclusions Estimates of silkworm domestication time are nearly consistent with the archeological evidence and our previous results. Importantly, we found that the bi-directional gene flow might occur during silkworm domestication. Our findings add a dimension to highlight the important role of gene flow in domestication of crops and animals. PMID:25123546

2014-01-01

3

Linkage disequilibrium and demographic history of wild and domestic canids.  

PubMed

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 approximately 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

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

2009-04-01

4

Demographic history of India and mtDNA-sequence diversity.  

PubMed Central

The demographic history of India was examined by comparing mtDNA sequences obtained from members of three culturally divergent Indian subpopulations (endogamous caste groups). While an inferred tree revealed some clustering according to caste affiliation, there was no clear separation into three genetically distinct groups along caste lines. Comparison of pairwise nucleotide difference distributions, however, did indicate a difference in growth patterns between two of the castes. The Brahmin population appears to have undergone either a rapid expansion or steady growth. The low-ranking Mukri caste, however, may have either maintained a roughly constant population size or undergone multiple bottlenecks during that period. Comparison of the Indian sequences to those obtained from other populations, using a tree, revealed that the Indian sequences, along with all other non-African samples, form a starlike cluster. This cluster may represent a major expansion, possibly originating in southern Asia, taking place at some point after modern humans initially left Africa. PMID:7717409

Mountain, J L; Hebert, J M; Bhattacharyya, S; Underhill, P A; Ottolenghi, C; Gadgil, M; Cavalli-Sforza, L L

1995-01-01

5

Life history strategy in herbaceous perennials: inferring demographic patterns from the aboveground dynamics  

E-print Network

of survival, fecun- dity, and demographic transitions among two life history stages: flowering and non on demographic transitions one, two, and three years after flowering. Our results suggested that this population­recapture models, in which transitions across years are allowed to vary with demographic events occurring across

Shefferson, Richard P.

6

Demographic history and rare allele sharing among human populations  

PubMed Central

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

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

2011-01-01

7

Demographic history and rare allele sharing among human populations.  

PubMed

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

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

2011-07-19

8

Inferring demographic history from a spectrum of shared haplotype lengths.  

PubMed

There has been much recent excitement about the use of genetics to elucidate ancestral history and demography. Whole genome data from humans and other species are revealing complex stories of divergence and admixture that were left undiscovered by previous smaller data sets. A central challenge is to estimate the timing of past admixture and divergence events, for example the time at which Neanderthals exchanged genetic material with humans and the time at which modern humans left Africa. Here, we present a method for using sequence data to jointly estimate the timing and magnitude of past admixture events, along with population divergence times and changes in effective population size. We infer demography from a collection of pairwise sequence alignments by summarizing their length distribution of tracts of identity by state (IBS) and maximizing an analytic composite likelihood derived from a Markovian coalescent approximation. Recent gene flow between populations leaves behind long tracts of identity by descent (IBD), and these tracts give our method power by influencing the distribution of shared IBS tracts. In simulated data, we accurately infer the timing and strength of admixture events, population size changes, and divergence times over a variety of ancient and recent time scales. Using the same technique, we analyze deeply sequenced trio parents from the 1000 Genomes project. The data show evidence of extensive gene flow between Africa and Europe after the time of divergence as well as substructure and gene flow among ancestral hominids. In particular, we infer that recent African-European gene flow and ancient ghost admixture into Europe are both necessary to explain the spectrum of IBS sharing in the trios, rejecting simpler models that contain less population structure. PMID:23754952

Harris, Kelley; Nielsen, Rasmus

2013-06-01

9

Inferring Demographic History from a Spectrum of Shared Haplotype Lengths  

PubMed Central

There has been much recent excitement about the use of genetics to elucidate ancestral history and demography. Whole genome data from humans and other species are revealing complex stories of divergence and admixture that were left undiscovered by previous smaller data sets. A central challenge is to estimate the timing of past admixture and divergence events, for example the time at which Neanderthals exchanged genetic material with humans and the time at which modern humans left Africa. Here, we present a method for using sequence data to jointly estimate the timing and magnitude of past admixture events, along with population divergence times and changes in effective population size. We infer demography from a collection of pairwise sequence alignments by summarizing their length distribution of tracts of identity by state (IBS) and maximizing an analytic composite likelihood derived from a Markovian coalescent approximation. Recent gene flow between populations leaves behind long tracts of identity by descent (IBD), and these tracts give our method power by influencing the distribution of shared IBS tracts. In simulated data, we accurately infer the timing and strength of admixture events, population size changes, and divergence times over a variety of ancient and recent time scales. Using the same technique, we analyze deeply sequenced trio parents from the 1000 Genomes project. The data show evidence of extensive gene flow between Africa and Europe after the time of divergence as well as substructure and gene flow among ancestral hominids. In particular, we infer that recent African-European gene flow and ancient ghost admixture into Europe are both necessary to explain the spectrum of IBS sharing in the trios, rejecting simpler models that contain less population structure. PMID:23754952

Harris, Kelley; Nielsen, Rasmus

2013-01-01

10

Multilocus patterns of nucleotide variability and the demographic and selection history of Drosophila melanogaster populations  

Microsoft Academic Search

Uncertainty about the demographic history of populations can hamper genome-wide scans for selection based on population genetic models. To obtain a portrait of the effects of demographic history on genome variability patterns in Drosophila melanogaster populations, we surveyed noncoding DNA polymorphism at 10 X-linked loci in large samples from three African and two non-African populations. All five populations show significant

Penelope R. Haddrill; Kevin R. Thornton; Brian Charlesworth; Peter Andolfatto

2007-01-01

11

Association of Generalized Joint Hypermobility With a History of Glenohumeral Joint Instability  

PubMed Central

Abstract Context: Little is known about the relationship among sex, generalized joint hypermobility, and glenohumeral joint instability. Objective: To examine the relationship among sex, generalized joint hypermobility scores, and a history of glenohumeral joint instability within a young, physically active cohort and to describe the incidence of generalized joint hypermobility within this population. Design: Cross-sectional cohort study. Setting: United States Military Academy at West Point, New York. Patients or Other Participants: Of the 1311 members of the entering freshman class of 2010, 1050 (80%) agreed to participate. Main Outcome Measure(s): Generalized joint hypermobility was assessed using the Beighton Scale. A history of glenohumeral joint instability was identified via a baseline questionnaire. Results: Most participants (78%) had no signs of generalized joint hypermobility. Only 11 volunteers (1.5%) had Beighton Scale scores of 4 or greater. Logistic regression analysis revealed a relationship between generalized joint hypermobility and a history of glenohumeral joint instability (P ?=? .023). When sex and race were controlled, those with a total Beighton Scale score of ?2 were nearly 2.5 times as likely (odds ratio ?=? 2.48, 95% confidence interval ?=? 1.19, 5.20, P ?=? .016) to have reported a history of glenohumeral joint instability. A relationship was observed between sex and nearly all individual Beighton Scale items. Although women had higher total Beighton Scale scores than men, sex (P ?=? .658) and race (P ?=? .410) were not related to a history of glenohumeral joint instability when other variables in the model were controlled. Conclusions: In these participants, generalized joint hypermobility and a history of glenohumeral joint instability were associated. PMID:20446838

Cameron, Kenneth L.; Duffey, Michele L.; DeBerardino, Thomas M.; Stoneman, Paul D.; Jones, Christopher J.; Owens, Brett D.

2010-01-01

12

Length Distributions of Identity by Descent Reveal Fine-Scale Demographic History  

PubMed Central

Data-driven studies of identity by descent (IBD) were recently enabled by high-resolution genomic data from large cohorts and scalable algorithms for IBD detection. Yet, haplotype sharing currently represents an underutilized source of information for population-genetics research. We present analytical results on the relationship between haplotype sharing across purportedly unrelated individuals and a population’s demographic history. We express the distribution of IBD sharing across pairs of individuals for segments of arbitrary length as a function of the population’s demography, and we derive an inference procedure to reconstruct such demographic history. The accuracy of the proposed reconstruction methodology was extensively tested on simulated data. We applied this methodology to two densely typed data sets: 500 Ashkenazi Jewish (AJ) individuals and 56 Kenyan Maasai (MKK) individuals (HapMap 3 data set). Reconstructing the demographic history of the AJ cohort, we recovered two subsequent population expansions, separated by a severe founder event, consistent with previous analysis of lower-throughput genetic data and historical accounts of AJ history. In the MKK cohort, high levels of cryptic relatedness were detected. The spectrum of IBD sharing is consistent with a demographic model in which several small-sized demes intermix through high migration rates and result in enrichment of shared long-range haplotypes. This scenario of historically structured demographies might explain the unexpected abundance of runs of homozygosity within several populations. PMID:23103233

Palamara, Pier Francesco; Lencz, Todd; Darvasi, Ariel; Pe'er, Itsik

2012-01-01

13

Recent Demographic History and Present Fine-Scale Structure in the Northwest Atlantic Leatherback  

E-print Network

Kwata NGO, 97300 Cayenne, French Guiana Abstract The leatherback turtle Dermochelys coriacea is the mostRecent Demographic History and Present Fine-Scale Structure in the Northwest Atlantic Leatherback (Dermochelys coriacea) Turtle Population E´rica Molfetti1 , Sibelle Torres Vilac¸a2 , Jean-Yves Georges3

Paris-Sud XI, Université de

14

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

E-print Network

IN THE MIDDLE MISSISSIPPI RIVER by Sara Joy Tripp B.A., Southern Illinois University, 2004 A Thesis Submitted the Life History and Demographics of Shovelnose Sturgeon in the Middle Mississippi River MAJOR PROFESSORS Mississippi River is one of the last commercially viable sturgeon populations in the world. To determine

15

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

PubMed Central

Great European mountain ranges have acted as barriers to gene flow for resident populations since prehistory and have offered a place for the settlement of small, and sometimes culturally diverse, communities. Therefore, the human groups that have settled in these areas are worth exploring as an important potential source of diversity in the genetic structure of European populations. In this study, we present new high resolution data concerning Y chromosomal variation in three distinct Alpine ethno-linguistic groups, Italian, Ladin and German. Combining unpublished and literature data on Y chromosome and mitochondrial variation, we were able to detect different genetic patterns. In fact, within and among population diversity values observed vary across linguistic groups, with German and Italian speakers at the two extremes, and seem to reflect their different demographic histories. Using simulations we inferred that the joint effect of continued genetic isolation and reduced founding group size may explain the apportionment of genetic diversity observed in all groups. Extending the analysis to other continental populations, we observed that the genetic differentiation of Ladins and German speakers from Europeans is comparable or even greater to that observed for well known outliers like Sardinian and Basques. Finally, we found that in south Tyroleans, the social practice of Geschlossener Hof, a hereditary norm which might have favored male dispersal, coincides with a significant intra-group diversity for mtDNA but not for Y chromosome, a genetic pattern which is opposite to those expected among patrilocal populations. Together with previous evidence regarding the possible effects of “local ethnicity” on the genetic structure of German speakers that have settled in the eastern Italian Alps, this finding suggests that taking socio-cultural factors into account together with geographical variables and linguistic diversity may help unveil some yet to be understood aspects of the genetic structure of European populations. PMID:24312576

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

2013-01-01

16

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

PubMed Central

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

Lam, David

2012-01-01

17

Genomic sequencing of Plasmodium falciparum malaria parasites from Senegal reveals the demographic history of the population.  

PubMed

Malaria is a deadly disease that causes nearly one million deaths each year. To develop methods to control and eradicate malaria, it is important to understand the genetic basis of Plasmodium falciparum adaptations to antimalarial treatments and the human immune system while taking into account its demographic history. To study the demographic history and identify genes under selection more efficiently, we sequenced the complete genomes of 25 culture-adapted P. falciparum isolates from three sites in Senegal. We show that there is no significant population structure among these Senegal sampling sites. By fitting demographic models to the synonymous allele-frequency spectrum, we also estimated a major 60-fold population expansion of this parasite population ?20,000-40,000 years ago. Using inferred demographic history as a null model for coalescent simulation, we identified candidate genes under selection, including genes identified before, such as pfcrt and PfAMA1, as well as new candidate genes. Interestingly, we also found selection against G/C to A/T changes that offsets the large mutational bias toward A/T, and two unusual patterns: similar synonymous and nonsynonymous allele-frequency spectra, and 18% of genes having a nonsynonymous-to-synonymous polymorphism ratio >1. PMID:22734050

Chang, Hsiao-Han; Park, Daniel J; Galinsky, Kevin J; Schaffner, Stephen F; Ndiaye, Daouda; Ndir, Omar; Mboup, Souleymane; Wiegand, Roger C; Volkman, Sarah K; Sabeti, Pardis C; Wirth, Dyann F; Neafsey, Daniel E; Hartl, Daniel L

2012-11-01

18

Effects of recent population bottlenecks on reconstructing the demographic history of prairie-chickens.  

PubMed

Current methods of DNA sequence analysis attempt to reconstruct historical patterns of population structure and growth from contemporary samples. However, these techniques may be influenced by recent population bottlenecks, which have the potential to eliminate lineages that reveal past changes in demography. One way to examine the performance of these demographic methods is to compare samples from populations before and after recent bottlenecks. We compared estimates of demographic history from populations of greater prairie-chickens (Tympanuchus cupido) before and after recent bottlenecks using four common methods (nested clade analysis [NCA], Tajima's D, mismatch distribution, and MDIV). We found that NCA did not perform well in the presence of bottleneck events, although it did recover some genetic signals associated with increased isolation and the extinction of intermediate populations. The majority of estimates for Tajima's D, including those from bottlenecked populations, were not significantly different from zero, suggesting our data conformed to neutral expectations. In contrast, mismatch distributions including the raggedness index were more likely to identify recently bottlenecked populations with this data set. Estimates of population mutation rate (theta), population divergence time (t), and time to the most recent common ancestor (TMRCA) from MDIV were similar before and after bottlenecks; however, estimates of gene flow (M) were significantly lower in a few cases following a bottleneck. These results suggest that caution should be used when assessing demographic history from contemporary data sets, as recently fragmented and bottlenecked populations may have lost lineages that affect inferences of their demographic history. PMID:17561885

Johnson, Jeff A; Dunn, Peter O; Bouzat, Juan L

2007-06-01

19

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

Microsoft Academic Search

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

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

1993-01-01

20

Multilocus dataset reveals demographic histories of two peat mosses in Europe  

PubMed Central

Background Revealing the past and present demographic history of populations is of high importance to evaluate the conservation status of species. Demographic data can be obtained by direct monitoring or by analysing data of historical and recent collections. Although these methods provide the most detailed information they are very time consuming. Another alternative way is to make use of the information accumulated in the species' DNA over its history. Recent development of the coalescent theory makes it possible to reconstruct the demographic history of species using nucleotide polymorphism data. To separate the effect of natural selection and demography, multilocus analysis is needed because these two forces can produce similar patterns of polymorphisms. In this study we investigated the amount and pattern of sequence variability of a Europe wide sample set of two peat moss species (Sphagnum fimbriatum and S. squarrosum) with similar distributions and mating systems but presumably contrasting historical demographies using 3 regions of the nuclear genome (appr. 3000 bps). We aimed to draw inferences concerning demographic, and phylogeographic histories of the species. Results All three nuclear regions supported the presence of an Atlantic and Non-Atlantic clade of S. fimbriatum suggesting glacial survival of the species along the Atlantic coast of Europe. Contrarily, S. squarrosum haplotypes showed three clades but no geographic structure at all. Maximum likelihood, mismatch and Bayesian analyses supported a severe historical bottleneck and a relatively recent demographic expansion of the Non-Atlantic clade of S. fimbriatum, whereas size of S. squarrosum populations has probably decreased in the past. Species wide molecular diversity of the two species was nearly the same with an excess of replacement mutations in S. fimbriatum. Similar levels of molecular diversity, contrasting phylogeographic patterns and excess of replacement mutations in S. fimbriatum compared to S. squarrosum mirror unexpected differences in the demography and population history of the species. Conclusion This study represents the first detailed European wide phylodemographic investigation on bryophytes and shows how pattern of nucleotide polymorphism can reveal unexpected differences in the population history of haploid plants with seemingly similar characteristics. PMID:17714592

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

2007-01-01

21

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

PubMed

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

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

2014-03-01

22

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

PubMed Central

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

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

2012-01-01

23

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

PubMed

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 (F(ST) = 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

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

2012-09-01

24

Insights into the demographic history of African Pygmies from complete mitochondrial genomes.  

PubMed

Pygmy populations are among the few hunter-gatherers currently living in sub-Saharan Africa and are mainly represented by two groups, Eastern and Western, according to their current geographical distribution. They are scattered across the Central African belt and surrounded by Bantu-speaking farmers, with whom they have complex social and economic interactions. To investigate the demographic history of Pygmy groups, a population approach was applied to the analysis of 205 complete mitochondrial DNA (mtDNA) sequences from ten central African populations. No sharing of maternal lineages was observed between the two Pygmy groups, with haplogroup L1c being characteristic of the Western group but most of Eastern Pygmy lineages falling into subclades of L0a, L2a, and L5. Demographic inferences based on Bayesian coalescent simulations point to an early split among the maternal ancestors of Pygmies and those of Bantu-speaking farmers (? 70,000 years ago [ya]). Evidence for population growth in the ancestors of Bantu-speaking farmers has been observed, starting ? 65,000 ya, well before the diffusion of Bantu languages. Subsequently, the effective population size of the ancestors of Pygmies remained constant over time and ? 27,000 ya, coincident with the Last Glacial Maximum, Eastern and Western Pygmies diverged, with evidence of subsequent migration only among the Western group and the Bantu-speaking farmers. Western Pygmies show signs of a recent bottleneck 4,000-650 ya, coincident with the diffusion of Bantu languages, whereas Eastern Pygmies seem to have experienced a more ancient decrease in population size (20,000-4,000 ya). In conclusion, the results of this first attempt at analyzing complete mtDNA sequences at the population level in sub-Saharan Africa not only support previous findings but also offer new insights into the demographic history of Pygmy populations, shedding new light on the ancient peopling of the African continent. PMID:21041797

Batini, Chiara; Lopes, Joao; Behar, Doron M; Calafell, Francesc; Jorde, Lynn B; van der Veen, Lolke; Quintana-Murci, Lluis; Spedini, Gabriella; Destro-Bisol, Giovanni; Comas, David

2011-02-01

25

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

PubMed

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

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

2014-11-01

26

Demographic history and the low genetic diversity in Dipteryx alata (Fabaceae) from Brazilian Neotropical savannas  

PubMed Central

Genetic effects of habitat fragmentation may be undetectable because they are generally a recent event in evolutionary time or because of confounding effects such as historical bottlenecks and historical changes in species' distribution. To assess the effects of demographic history on the genetic diversity and population structure in the Neotropical tree Dipteryx alata (Fabaceae), we used coalescence analyses coupled with ecological niche modeling to hindcast its distribution over the last 21?000 years. Twenty-five populations (644 individuals) were sampled and all individuals were genotyped using eight microsatellite loci. All populations presented low allelic richness and genetic diversity. The estimated effective population size was small in all populations and gene flow was negligible among most. We also found a significant signal of demographic reduction in most cases. Genetic differentiation among populations was significantly correlated with geographical distance. Allelic richness showed a spatial cline pattern in relation to the species' paleodistribution 21?kyr BP (thousand years before present), as expected under a range expansion model. Our results show strong evidences that genetic diversity in D. alata is the outcome of the historical changes in species distribution during the late Pleistocene. Because of this historically low effective population size and the low genetic diversity, recent fragmentation of the Cerrado biome may increase population differentiation, causing population decline and compromising long-term persistence. PMID:23591520

Collevatti, R G; Telles, M P C; Nabout, J C; Chaves, L J; Soares, T N

2013-01-01

27

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

PubMed

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

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

28

Neutral nuclear variation in Baboons (genus Papio) provides insights into their evolutionary and demographic histories.  

PubMed

Baboons (genus Papio) are distributed over most of sub-Saharan Africa and in the southern portion of the Arabian Peninsula. Six distinct morphotypes, with clearly defined geographic distributions, are recognized (the olive, chacma, yellow, Guinea, Kinda, and hamadryas baboons). The evolutionary relationships among baboon forms have long been a controversial issue. Phylogenetic analyses based on mitochondrial DNA sequences revealed that the modern baboon morphotypes are mitochondrially paraphyletic or polyphyletic. The discordance between mitochondrial lineages and morphology is indicative of extensive introgressive hybridization between ancestral baboon populations. To gain insights into the evolutionary relationships among morphotypes and their demographic history, we performed an analysis of nuclear variation in baboons. We sequenced 13 noncoding, putatively neutral, nuclear regions, and scored the presence/absence of 18 polymorphic transposable elements in a sample of 45 baboons belonging to five of the six recognized baboon forms. We found that the chacma baboon is the sister-taxon to all other baboons and the yellow baboon is the sister-taxon to an unresolved northern clade containing the olive, Guinea, and hamadryas baboons. We estimated that the diversification of baboons occurred entirely in the Pleistocene, the earliest split dating ?1.5 million years ago, and that baboons have experienced relatively large and constant effective population sizes for most of their evolutionary history (?30,000 to 95,000 individuals). Am J Phys Anthropol 155:621-634, 2014. © 2014 Wiley Periodicals, Inc. PMID:25234435

Boissinot, Stéphane; Alvarez, Lauren; Giraldo-Ramirez, Juliana; Tollis, Marc

2014-12-01

29

BA Joint Honours History and American Studies (3 years) VT17  

E-print Network

of history, including political, social, cultural and military aspects. In the final year students undertakeBA Joint Honours History and American Studies (3 years) VT17 American Studies (4 years) TV71 Ancient History (3 years) V110 Ancient History (4 years) V190 Classical Civilisation (3 years) QV81

Harman, Neal.A.

30

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

Microsoft Academic Search

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

Ron Lesthaeghe; Johan Surkyn

31

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

PubMed Central

The pen shell, Atrina pectinata, is one of the commercial bivalves in East Asia and thought to be recently affected by anthropogenic pressure (habitat destruction and/or fishing pressure). Information on its population genetic structure is crucial for the conservation of A. pectinata. Considering its long pelagic larval duration and iteroparity with high fecundity, the genetic structure for A. pectinata could be expected to be weak at a fine scale. However, the unusual oceanography in the coasts of China and Korea suggests potential for restricted dispersal of pelagic larvae and geographical differentiation. In addition, environmental changes associated with Pleistocene sea level fluctuations on the East China Sea continental shelf may also have strongly influenced historical population demography and genetic diversity of marine organisms. Here, partial sequences of the mitochondrial Cytochrome c oxidase subunit I (COI) gene and seven microsatellite loci were used to estimate population genetic structure and demographic history of seven samples from Northern China coast and one sample from North Korea coast. Despite high levels of genetic diversity within samples, there was no genetic differentiation among samples from Northern China coast and low but significant genetic differentiation between some of the Chinese samples and the North Korean sample. A late Pleistocene population expansion, probably after the Last Glacial Maximum, was also demonstrated for A. pectinata samples. No recent genetic bottleneck was detected in any of the eight samples. We concluded that both historical recolonization (through population range expansion and demographic expansion in the late Pleistocene) and current gene flow (through larval dispersal) were responsible for the weak level of genetic structure detected in A. pectinata. PMID:24789175

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

2014-01-01

32

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

PubMed

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

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

2014-01-01

33

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

PubMed Central

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

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

34

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

PubMed

The population sizes of three Korean indigenous cattle populations have been drastically reduced over the past decades. In this study, we examined the extent to which reduction in populations influenced genetic diversity, population structure and demographic history using complete mitochondrial DNA (mtDNA) control region sequences. The complete mtDNA control region was sequenced in 56 individuals from Korean Black (KB), Jeju Black (JEB) and Korean Brindle (BRI) cattle populations. We included 27 mtDNA sequences of Korean Brown (BRO) from the GenBank database. Haplotype diversity estimate for the total population was high (0.870) while nucleotide diversity was low (0.004). The KB showed considerably low nucleotide (? = 0.001) and haplotype (h = 0.368) diversities. Analysis of molecular variance revealed a low level of genetic differentiation but this was highly significant (p<0.001) among the cattle populations. Of the total genetic diversity, 7.6% was attributable to among cattle populations diversity and the rest (92.4%) to differences within populations. The mismatch distribution analysis and neutrality tests revealed that KB population was in genetic equilibrium or decline. Indeed, unless an appropriate breeding management practice is developed, inbreeding and genetic drift will further impoverish genetic diversity of these cattle populations. Rational breed development and conservation strategy is needed to safeguard these cattle population. PMID:25049684

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

2012-09-01

35

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

PubMed Central

The ragged topography created by orogenesis generates diversified habitats for plants in Taiwan. In addition to colonization from nearby mainland China, high species diversity and endemism of plants is also present in Taiwan. Five of the seven Scutellaria species (Lamiaceae) in Taiwan, for example, are endemic to the island. Hypotheses of multiple sources or in situ radiation have arisen to explain the high endemism of Taiwanese species. In this study, phylogenetic analyses using both nuclear and chloroplast markers revealed the multiple sources of Taiwanese Scutellaria species and confirmed the rapid and recent speciation of endemic species, especially those of the “indica group” composed of S. indica, S. austrotaiwanensis, S. tashiroi, and S. playfairii. The common ancestors of the indica group colonized first in northern Taiwan and dispersed regionally southward and eastward. Climate changes during glacial/interglacial cycles led to gradual colonization and variance events in the ancestors of these species, resulting in the present distribution and genetic differentiation of extant populations. Population decline was also detected in S. indica, which might reflect a bottleneck effect from the glacials. In contrast, the recently speciated endemic members of the indica group have not had enough time to accumulate much genetic variation and are thus genetically insensitive to demographic fluctuations, but the extant lineages were spatially expanded in the coalescent process. This study integrated phylogenetic and population genetic analyses to illustrate the evolutionary history of Taiwanese Scutellaria of high endemism and may be indicative of the diversification mechanism of plants on continental islands. PMID:23226402

Liao, Pei-Chun

2012-01-01

36

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

PubMed Central

Background The Salangid icefish Neosalanx taihuensis (Salangidae) is an economically important fish, which is endemic to China, restricted to large freshwater systems (e.g. lakes, large rivers and estuaries) and typically exhibit low vagility. The continuous distribution ranges from the temperate region of the Huai and Yellow River basins to the subtropical region of the Pearl River basin. This wide ranging distribution makes the species an ideal model for the study of palaeoclimatic effects on population genetic structure and phylogeography. Here, we aim to analyze population genetic differentiation within and between river basins and demographic history in order to understand how this species responded to severe climatic oscillations, decline of the sea levels during the Pleistocene ice ages and tectonic activity. Results We obtained the complete mtDNA cytochrome b sequences (1141 bp) of 354 individuals from 13 populations in the Pearl River, the Yangze River and the Huai River basin. Thirty-six haplotypes were detected. Haplotype frequency distributions were strongly skewed, with most haplotypes (n = 24) represented only in single samples each and thus restricted to a single population. The most common haplotype (H36) was found in 49.15% of all individuals. Analysis of molecular variance (AMOVA) revealed a random pattern in the distribution of genetic diversity, which is inconsistent with contemporary hydrological structure. Significant levels of genetic subdivision were detected among populations within basins rather than between the three basins. Demographic analysis revealed that the population size in the Pearl River basin has remained relatively constant whereas the populations in the Yangze River and the Huai River basins expanded about 221 and 190 kyr ago, respectively, with the majority of mutations occurring after the last glacial maximum (LGM). Conclusion The observed complex genetic pattern of N. taihuensis is coherent with a scenario of multiple unrelated founding events by long-distance colonization and dispersal combined with contiguous population expansion and locally restricted gene flow. We also found that this species was likely severely impacted by past glaciations. More favourable climate and the formation of large suitable habitations together facilitated population expansion after the late Quaternary (especially the LGM). We proposed that all populations should be managed and conserved separately, especially for habitat protection. PMID:18625046

2008-01-01

37

Comparative Evaluation of a Joint Lecture-Discussion Approach to U. S. History.  

ERIC Educational Resources Information Center

In fall 1970 several sections of a one-semester required U.S. history course (History 27: American History and Constitution) at Cerritos College (California) were combined into a joint lecture-discussion (JL) for 200 or more students. The opportunities for providing two lecturers stressing their topical specialties in group discussions seemed…

Hinrichsen, Keith A.; Schaumburg, Gary F.

38

Demographic and genetic invasion history of a 9-year-old roadside population of Bunias orientalis L. (Brassicaceae)  

Microsoft Academic Search

The population history of a 9-year-old roadside population of the invasive plant Bunias orientalis was reconstructed by demographic analysis including size, position, age (determined by herbchronology) and RAPD-PCR patterns\\u000a of individual plants. We evaluated emerging patterns of population growth and genetic structure during a full period of population\\u000a development under typical site conditions (anthropogenic disturbance) and their possible consequences for

Hansjörg Dietz; Markus Fischer; Bernhard Schmid

1999-01-01

39

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

Microsoft Academic Search

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.

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

2008-01-01

40

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

PubMed

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

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

2013-06-01

41

Mating-System Variation, Demographic History and Patterns of Nucleotide Diversity in the Tristylous Plant Eichhornia paniculata  

PubMed Central

Inbreeding in highly selfing populations reduces effective size and, combined with demographic conditions associated with selfing, this can erode genetic diversity and increase population differentiation. Here we investigate the role that variation in mating patterns and demographic history play in shaping the distribution of nucleotide variation within and among populations of the annual neotropical colonizing plant Eichhornia paniculata, a species with wide variation in selfing rates. We sequenced 10 EST-derived nuclear loci in 225 individuals from 25 populations sampled from much of the geographic range and used coalescent simulations to investigate demographic history. Highly selfing populations exhibited moderate reductions in diversity but there was no significant difference in variation between outcrossing and mixed mating populations. Population size interacted strongly with mating system and explained more of the variation in diversity within populations. Bayesian structure analysis revealed strong regional clustering and selfing populations were highly differentiated on the basis of an analysis of Fst. There was no evidence for a significant loss of within-locus linkage disequilibrium within populations, but regional samples revealed greater breakdown in Brazil than in selfing populations from the Caribbean. Coalescent simulations indicate a moderate bottleneck associated with colonization of the Caribbean from Brazil ?125,000 years before the present. Our results suggest that the recent multiple origins of selfing in E. paniculata from diverse outcrossing populations result in higher diversity than expected under long-term equilibrium. PMID:19917767

Ness, Rob W.; Wright, Stephen I.; Barrett, Spencer C. H.

2010-01-01

42

Inference of demographic history from genealogical trees using reversible jump Markov chain Monte Carlo  

Microsoft Academic Search

BACKGROUND: Coalescent theory is a general framework to model genetic variation in a population. Specifically, it allows inference about population parameters from sampled DNA sequences. However, most currently employed variants of coalescent theory only consider very simple demographic scenarios of population size changes, such as exponential growth. RESULTS: Here we develop a coalescent approach that allows Bayesian non-parametric estimation of

Rainer Opgen-Rhein; Ludwig Fahrmeir; Korbinian Strimmer

2005-01-01

43

Effects of recent population bottlenecks on reconstructing the demographic history of prairie-chickens  

Microsoft Academic Search

Current methods of DNA sequence analysis attempt to reconstruct historical patterns of population structure and growth from contemporary samples. However, these techniques may be influenced by recent population bottlenecks, which have the potential to eliminate lineages that reveal past changes in demography. One way to examine the performance of these demographic methods is to compare samples from populations before and

JEFF A. J OHNSON; PETER O. DUNN; JUAN L. B OUZAT

2007-01-01

44

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

PubMed Central

Objective To determine the proportion of emergency department (ED) patients who have been tested for human immunodeficiency virus (HIV) infection and assess if patient history of HIV testing varies according to patient demographic characteristics. Design From July 2005–July 2006, a random sample of 18–55-year-old English-speaking patients being treated for sub-critical injury or illness at a northeastern US ED were interviewed on their history of HIV testing. Logistic regression models were created to compare patients by their history of being tested for HIV according to their demography. Odds ratios (ORs) with 95% confidence intervals (CIs) were estimated. Results Of 2107 patients surveyed who were not known to be HIV-infected, the median age was 32 years; 54% were male, 71% were white, and 45% were single/never married; 49% had private health-care insurance and 45% had never been tested for HIV. Of the 946 never previously tested for HIV, 56.1% did not consider themselves at risk for HIV. In multivariable logistic regression analyses, those less likely to have been HIV tested were male (OR: 1.32 [1.37–2.73]), white (OR: 1.93 [1.37–2.73]), married (OR: 1.53 [1.12–2.08]), and had private health-care insurance (OR: 2.10 [1.69–2.61]). There was a U-shaped relationship between age and history of being tested for HIV; younger and older patients were less likely to have been tested. History of HIV testing and years of formal education were not related. Conclusion Almost half of ED patients surveyed had never been tested for HIV. Certain demographic groups are being missed though HIV diagnostic testing and screening programmes in other settings. These groups could potentially be reached through universal screening. PMID:19564517

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

2011-01-01

45

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

PubMed Central

Background C. gloeosporioides sensu lato is one of the most economically important post-harvest diseases affecting papaya production worldwide. There is currently no information concerning the genetic structure or demographic history of this pathogen in any of the affected countries. Knowledge of molecular demographic parameters for different populations will improve our understanding of the biogeographic history as well as the evolutionary and adaptive potential of these pathogens. In this study, sequence data for ACT, GPDH, ?-TUB and ITS gene regions were analyzed for C. gloeosporioides sensu lato and C. truncatum isolates infecting papaya in Trinidad and Mexico in order to determine the genetic structure and demographic history of these populations. Results The data indicated that Mexico is the ancestral C. gloeosporioides sensu lato population with asymmetrical migration to Trinidad. Mexico also had the larger effective population size but, both Mexico and Trinidad populations exhibited population expansion. Mexico also had greater nucleotide diversity and high levels of diversity for each gene. There was significant sub-division of the Trinidad and Mexico populations and low levels of genetic divergence among populations for three of the four gene regions; ?-TUB was shown to be under positive selection. There were also dissimilar haplotype characteristics for both populations. Mutation may play a role in shaping the population structure of C. gloeosporioides sensu lato isolates from Trinidad and from Mexico, especially with respect to the ACT and GPDH gene regions. There was no evidence of gene flow between the C. truncatum populations and it is possible that the Mexico and Trinidad populations emerged independently of each other. Conclusions The study revealed relevant information based on the genetic structure as well as the demographic history of two fungal pathogens infecting papaya, C. gloeosporioides sensu lato and C. truncatum, in Trinidad and Mexico. Understanding the genetic structure of pathogen populations will assist in determining the evolutionary potential of the pathogen and in identifying which evolutionary forces may have the greatest impact on durability of resistance. Intervention strategies that target these evolutionary forces would prove to be the most practical. PMID:23800297

2013-01-01

46

Impact of Quaternary climatic changes and interspecific competition on the demographic history of a highly mobile generalist carnivore, the coyote.  

PubMed

Recurrent cycles of climatic change during the Quaternary period have dramatically affected the population genetic structure of many species. We reconstruct the recent demographic history of the coyote (Canis latrans) through the use of Bayesian techniques to examine the effects of Late Quaternary climatic perturbations on the genetic structure of a highly mobile generalist species. Our analysis reveals a lack of phylogeographic structure throughout the range but past population size changes correlated with climatic changes. We conclude that even generalist carnivorous species are very susceptible to environmental changes associated with climatic perturbations. This effect may be enhanced in coyotes by interspecific competition with larger carnivores. PMID:22491760

Koblmüller, Stephan; Wayne, Robert K; Leonard, Jennifer A

2012-08-23

47

Inferring the Demographic History of African Farmers and Pygmy Hunter-Gatherers Using a Multilocus Resequencing Data Set  

PubMed Central

The transition from hunting and gathering to farming involved a major cultural innovation that has spread rapidly over most of the globe in the last ten millennia. In sub-Saharan Africa, hunter–gatherers have begun to shift toward an agriculture-based lifestyle over the last 5,000 years. Only a few populations still base their mode of subsistence on hunting and gathering. The Pygmies are considered to be the largest group of mobile hunter–gatherers of Africa. They dwell in equatorial rainforests and are characterized by their short mean stature. However, little is known about the chronology of the demographic events—size changes, population splits, and gene flow—ultimately giving rise to contemporary Pygmy (Western and Eastern) groups and neighboring agricultural populations. We studied the branching history of Pygmy hunter–gatherers and agricultural populations from Africa and estimated separation times and gene flow between these populations. We resequenced 24 independent noncoding regions across the genome, corresponding to a total of ?33 kb per individual, in 236 samples from seven Pygmy and five agricultural populations dispersed over the African continent. We used simulation-based inference to identify the historical model best fitting our data. The model identified included the early divergence of the ancestors of Pygmy hunter–gatherers and farming populations ?60,000 years ago, followed by a split of the Pygmies' ancestors into the Western and Eastern Pygmy groups ?20,000 years ago. Our findings increase knowledge of the history of the peopling of the African continent in a region lacking archaeological data. An appreciation of the demographic and adaptive history of African populations with different modes of subsistence should improve our understanding of the influence of human lifestyles on genome diversity. PMID:19360089

Patin, Etienne; Laval, Guillaume; Barreiro, Luis B.; Salas, Antonio; Semino, Ornella; Santachiara-Benerecetti, Silvana; Kidd, Kenneth K.; Kidd, Judith R.; Van der Veen, Lolke; Hombert, Jean-Marie; Gessain, Antoine; Froment, Alain; Bahuchet, Serge; Heyer, Evelyne; Quintana-Murci, Lluis

2009-01-01

48

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

PubMed

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

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

2013-03-01

49

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

ERIC Educational Resources Information Center

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…

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

2006-01-01

50

Relationships among and between ELL Status, Demographic Characteristics, Enrollment History, and School Persistence. CRESST Report 810  

ERIC Educational Resources Information Center

This report examines enrollment history, achievement gaps, and persistence in school for ELL students and reclassified ELL students as compared to non-ELL students. The study uses statewide individual-level data sets merged from students' entry to exit in the state's public school system for graduate cohorts of 2006, 2007, and 2008. Analytic…

Kim, Jinok

2011-01-01

51

Utilizing spatial demographic and life history variation to optimize sustainable yield of a temperate sex-changing fish.  

PubMed

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

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

2011-01-01

52

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

PubMed Central

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

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

2011-01-01

53

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

PubMed

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

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

2014-11-01

54

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

PubMed Central

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

Campbell, Michael C.; Tishkoff, Sarah A.

2010-01-01

55

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

PubMed

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

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

2011-07-01

56

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

PubMed

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

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

2011-01-01

57

The contribution of parental smoking history and socio-demographic factors to the smoking behavior of Israeli women.  

PubMed

This study examined the interplay between sociodemographic factors and parental smoking history in shaping the smoking behavior of Israeli women (N = 302). The study was conducted in the Negev region, which is characterized by a high proportion of immigrants and high percentage of low socioeconomic and educational groups. The specific objectives of this study were to examine: (1) The prevalence and characteristics of women smokers, ex-smokers and never-smokers; and (2) the contribution of education and parent smoking history to women's current smoking. Low levels of education, being Israeli born or veteran immigrants of European-American origin significantly increased the risk of smoking, whereas an orthodox lifestyle and new immigrant status significantly reduced the likelihood of smoking. Occasional smokers reported significantly higher primary care utilization than never smokers. A significant relationship between smoking and pain, gynecological symptoms and depression was found. Results indicate that childhood exposure to maternal smoking was a significant risk factor for smoking, whereas paternal past smoking negatively affects smoking in women. Also, results show that parental educational level affects women's smoking behavior indirectly by influencing their own educational attainment, which in turn is negatively associated with the likelihood of smoking. Mothers with higher education were more likely to smoke, an effect that was reversed for their daughters. Our results demonstrate how demographic, parental and lifestyle factors affect women's smoking in a multi-ethnic society and highlight the need to examine both generational and intergenerational effects. PMID:24266386

Segal-Engelchin, Dorit; Friedmann, Enav; Cwikel, Julie G

2014-12-01

58

Population Genomic Analysis Reveals a Rich Speciation and Demographic History of Orang-utans (Pongo pygmaeus and Pongo abelii)  

PubMed Central

To gain insights into evolutionary forces that have shaped the history of Bornean and Sumatran populations of orang-utans, we compare patterns of variation across more than 11 million single nucleotide polymorphisms found by previous mitochondrial and autosomal genome sequencing of 10 wild-caught orang-utans. Our analysis of the mitochondrial data yields a far more ancient split time between the two populations (?3.4 million years ago) than estimates based on autosomal data (0.4 million years ago), suggesting a complex speciation process with moderate levels of primarily male migration. We find that the distribution of selection coefficients consistent with the observed frequency spectrum of autosomal non-synonymous polymorphisms in orang-utans is similar to the distribution in humans. Our analysis indicates that 35% of genes have evolved under detectable negative selection. Overall, our findings suggest that purifying natural selection, genetic drift, and a complex demographic history are the dominant drivers of genome evolution for the two orang-utan populations. PMID:24194868

Ma, Xin; Kelley, Joanna L.; Eilertson, Kirsten; Musharoff, Shaila; Degenhardt, Jeremiah D.; Martins, Andre L.; Vinar, Tomas; Kosiol, Carolin; Siepel, Adam; Gutenkunst, Ryan N.; Bustamante, Carlos D.

2013-01-01

59

Allelic disequilibrium and allele frequency distribution as a function of social and demographic history.  

PubMed Central

Allelic disequilibrium between closely linked genes is a common observation in human populations and often gives rise to speculation concerning the role of selective forces. In a previous treatment, we have developed a population model of the expected distribution of rare variants (including private polymorphisms) in Amerindians and have argued that, because of the great expansion of Amerindian numbers with the advent of agriculture, most of these rare variants are of relatively recent origin. Many other populations have similar histories of striking recent expansions. In this treatment, we demonstrate that, in consequence of this fact, a high degree of linkage disequilibrium between two nonhomologous alleles <0.5 cM apart is the "normal" expectation, even in the absence of selection. This expectation is enhanced by the previous subdivision of human populations into relatively isolated tribes characterized by a high level of endogamy and inbreeding. We also demonstrate that the alleles associated with a recessive disease phenotype are expected to exist in a population in very variable frequencies: there is no need to postulate positive selection with respect to the more common disease-associated alleles for such entities as phenylketonuria or cystic fibrosis. PMID:8981963

Thompson, E A; Neel, J V

1997-01-01

60

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

PubMed Central

Background Environmental preferences and past climatic changes may determine the length of time during which a species range has contracted or expanded from refugia, thereby influencing levels of genetic diversification. Connectivity among populations of steppe-associated taxa might have been maximal during the long glacial periods, and interrupted only during the shorter interglacial phases, potentially resulting in low levels of genetic differentiation among populations. We investigated this hypothesis by exploring patterns of genetic diversity, past demography and gene flow in a raptor species characteristic of steppes, the Montagu's harrier (Circus pygargus), using mitochondrial DNA data from 13 breeding populations and two wintering populations. Results Consistent with our hypothesis, Montagu's harrier has relatively low genetic variation at the mitochondrial DNA. The highest levels of genetic diversity were found in coastal Spain, France and central Asia. These areas, which were open landscapes during the Holocene, may have acted as refugia when most of the European continent was covered by forests. We found significant genetic differentiation between two population groups, at the SW and NE parts of the species' range. Two events of past population growth were detected, and occurred ca. 7500-5500 and ca. 3500-1000 years BP in the SW and NE part of the range respectively. These events were likely associated with vegetation shifts caused by climate and human-induced changes during the Holocene. Conclusions The relative genetic homogeneity observed across populations of this steppe raptor may be explained by a short isolation time, relatively recent population expansions and a relaxed philopatry. We highlight the importance of considering the consequence of isolation and colonization processes in order to better understand the evolutionary history of steppe species. PMID:22093489

2011-01-01

61

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

USGS Publications Warehouse

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.

Bowers, J.E.

1997-01-01

62

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

PubMed

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

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

2010-01-01

63

Understanding patterns of genetic diversity in the oak gallwasp Biorhiza pallida: demographic history or a Wolbachia selective sweep?  

PubMed

The endosymbiont Wolbachia can be responsible for selective sweeps on mitochondrial DNA variability within species. Similar signals can also result from demographic processes, although crucially the latter affect nuclear as well as mitochondrial loci. Here we present data on Wolbachia infection status and phylogeographic patterning for a widely distributed insect host, the oak gallwasp Biorhiza pallida (Hymenoptera: Cynipidae). Two hundred and eighteen females from eight European countries were screened for Wolbachia. All individuals from Hungary, Italy, France, U.K., Ireland, Switzerland, Sweden, and northern and southern Spain were infected with a single group A strain of Wolbachia, while populations in central Spain were not infected. A mitochondrial marker (cytochrome b) shows low variation and departure from neutrality in infected populations, but greater variation and no deviation from neutrality in Wolbachia-free populations. This pattern is compatible with a Wolbachia-induced selective sweep. However, we also find parallel differences between infected and uninfected populations for nuclear markers (sequence data for ITS1 and ITS2). All markers support the existence of a deep split between populations in Spain (some free of Wolbachia), and those in the rest of Europe (all infected). Allelic variation for five allozyme loci is also consistent with the Spain-rest of Europe split. Concordant patterns for nuclear and mitochondrial markers suggest that differences in the nature and extent of genetic diversity between these two regions are best explained by differing demographic histories (perhaps associated with range expansion from Pleistocene glacial refugia), rather than a Wolbachia-associated selective sweep. PMID:11737276

Rokas, A; Atkinson, R J; Brown, G S; West, S A; Stone, G N

2001-09-01

64

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

65

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

PubMed Central

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

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

2013-01-01

66

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

PubMed

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

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

2013-01-01

67

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

PubMed Central

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

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

2014-01-01

68

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

PubMed Central

Background Understanding the demographic history of a population is critical to conservation and to our broader understanding of evolutionary processes. For many tropical large mammals, however, this aim is confounded by the absence of fossil material and by the misleading signal obtained from genetic data of recently fragmented and isolated populations. This is particularly true for the lion which as a consequence of millennia of human persecution, has large gaps in its natural distribution and several recently extinct populations. Results We sequenced mitochondrial DNA from museum-preserved individuals, including the extinct Barbary lion (Panthera leo leo) and Iranian lion (P. l. persica), as well as lions from West and Central Africa. We added these to a broader sample of lion sequences, resulting in a data set spanning the historical range of lions. Our Bayesian phylogeographical analyses provide evidence for highly supported, reciprocally monophyletic lion clades. Using a molecular clock, we estimated that recent lion lineages began to diverge in the Late Pleistocene. Expanding equatorial rainforest probably separated lions in South and East Africa from other populations. West African lions then expanded into Central Africa during periods of rainforest contraction. Lastly, we found evidence of two separate incursions into Asia from North Africa, first into India and later into the Middle East. Conclusions We have identified deep, well-supported splits within the mitochondrial phylogeny of African lions, arguing for recognition of some regional populations as worthy of independent conservation. More morphological and nuclear DNA data are now needed to test these subdivisions. PMID:24690312

2014-01-01

69

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

PubMed Central

An understanding of population structure and genetic diversity is crucial for wildlife conservation and for determining the integrity of wildlife populations. The vulnerable Chinese cobra (Naja atra) has a distribution from the mouth of the Yangtze River down to northern Vietnam and Laos, within which several large mountain ranges and water bodies may influence population structure. We combined 12 microsatellite loci and 1117 bp of the mitochondrial cytochrome b gene to explore genetic structure and demographic history in this species, using 269 individuals from various localities in Mainland China and Vietnam. High levels of genetic variation were identified for both mtDNA and microsatellites. mtDNA data revealed two main (Vietnam + southern China + southwestern China; eastern + southeastern China) and one minor (comprising only two individuals from the westernmost site) clades. Microsatellite data divided the eastern + southeastern China clade further into two genetic clusters, which include individuals from the eastern and southeastern regions, respectively. The Luoxiao and Nanling Mountains may be important barriers affecting the diversification of lineages. In the haplotype network of cytchrome b, many haplotypes were represented within a “star” cluster and this and other tests suggest recent expansion. However, microsatellite analyses did not yield strong evidence for a recent bottleneck for any population or genetic cluster. The three main clusters identified here should be considered as independent management units for conservation purposes. The release of Chinese cobras into the wild should cease unless their origin can be determined, and this will avoid problems arising from unnatural homogenization. PMID:22558439

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

2012-01-01

70

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

PubMed Central

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

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

2013-01-01

71

Invasion history and demographic pattern of Cryphonectria hypovirus 1 across European populations of the chestnut blight fungus.  

PubMed

We reconstructed the invasion history of the fungal virus Cryphonectria hypovirus 1 (CHV-1) in Europe, which infects the chestnut blight fungus Cryphonectria parasitica. The pattern of virus evolution was inferred based on nucleotide sequence variation from isolates sampled across a wide area in Europe at different points in time. Phylogeny and time estimates suggested that CHV-1 was introduced together with its fungal host to Europe and that it rapidly colonized the central range along the south facing slopes of the Alps and the north-east facing slopes of the Dinaric Alps. These central populations were the source for two waves of simultaneous invasions toward the southern Balkans and Turkey, as indicated by migration rates. Our results showed that the evolutionary scenarios for CHV-1 and C. parasitica were spatially congruent. As infection with CHV-1 reduces the pathogenicity of C. parasitica toward the chestnut tree, CHV-1 invasions of the newly established C. parasitica populations probably prevented the development of devastating chestnut blight epidemics in Europe. We propose that in this, and supposedly in other pathosystems, geographic, vegetation-related, demographic, economic, and political factors may help explain the correlated invasion pattern of a parasite and its host. PMID:23301186

Bryner, Sarah F; Rigling, Daniel; Brunner, Patrick C

2012-12-01

72

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

PubMed

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

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

2014-06-01

73

Reconciling deep calibration and demographic history: bayesian inference of post glacial colonization patterns in Carcinus aestuarii (Nardo, 1847) and C. maenas (Linnaeus, 1758).  

PubMed

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

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

2011-01-01

74

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

PubMed Central

A precise inference of past demographic histories including dating of demographic events using Bayesian methods can only be achieved with the use of appropriate molecular rates and evolutionary models. Using a set of 596 mitochondrial cytochrome c oxidase I (COI) sequences of two sister species of European green crabs of the genus Carcinus (C. maenas and C. aestuarii), our study shows how chronologies of past evolutionary events change significantly with the application of revised molecular rates that incorporate biogeographic events for calibration and appropriate demographic priors. A clear signal of demographic expansion was found for both species, dated between 10,000 and 20,000 years ago, which places the expansions events in a time frame following the Last Glacial Maximum (LGM). In the case of C. aestuarii, a population expansion was only inferred for the Adriatic-Ionian, suggestive of a colonization event following the flooding of the Adriatic Sea (18,000 years ago). For C. maenas, the demographic expansion inferred for the continental populations of West and North Europe might result from a northward recolonization from a southern refugium when the ice sheet retreated after the LGM. Collectively, our results highlight the importance of using adequate calibrations and demographic priors in order to avoid considerable overestimates of evolutionary time scales. PMID:22164307

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

2011-01-01

75

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

Microsoft Academic Search

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

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

76

The allele frequency spectrum in genome-wide human variation data reveals signals of differential demographic history in three large world populations.  

PubMed

We have studied a genome-wide set of single-nucleotide polymorphism (SNP) allele frequency measures for African-American, East Asian, and European-American samples. For this analysis we derived a simple, closed mathematical formulation for the spectrum of expected allele frequencies when the sampled populations have experienced nonstationary demographic histories. The direct calculation generates the spectrum orders of magnitude faster than coalescent simulations do and allows us to generate spectra for a large number of alternative histories on a multidimensional parameter grid. Model-fitting experiments using this grid reveal significant population-specific differences among the demographic histories that best describe the observed allele frequency spectra. European and Asian spectra show a bottleneck-shaped history: a reduction of effective population size in the past followed by a recent phase of size recovery. In contrast, the African-American spectrum shows a history of moderate but uninterrupted population expansion. These differences are expected to have profound consequences for the design of medical association studies. The analytical methods developed for this study, i.e., a closed mathematical formulation for the allele frequency spectrum, correcting the ascertainment bias introduced by shallow SNP sampling, and dealing with variable sample sizes provide a general framework for the analysis of public variation data. PMID:15020430

Marth, Gabor T; Czabarka, Eva; Murvai, Janos; Sherry, Stephen T

2004-01-01

77

Demographic Perspectives A Demographic Perspective  

E-print Network

: Malthusian perspective Marxist perspective Cornucopianism Demographic Transition Other theories Premodern1 Demographic Perspectives A Demographic Perspective Two aspects: Mathematical and biomedical are the consequences of population change? Demographic Perspectives Premodern population doctrines Three major camps

Huang, Youqin

78

Understanding patterns of genetic diversity in the oak gallwasp Biorhiza pallida: demographic history or a Wolbachia selective sweep?  

Microsoft Academic Search

The endosymbiont Wolbachia can be responsible for selective sweeps on mitochondrial DNA variability within species. Similar signals can also result from demographic processes, although crucially the latter affect nuclear as well as mitochondrial loci. Here we present data on Wolbachia infection status and phylogeographic patterning for a widely distributed insect host, the oak gallwasp Biorhiza pallida (Hymenoptera: Cynipidae). Two hundred

Antonis Rokas; Rachel J Atkinson; Gordon S Brown; Stuart A West; Graham N Stone

2001-01-01

79

Effects of footwear on lead limb knee and ankle joint kinematics in a fast bowler with a history of posterior ankle joint impingement-a case report.  

PubMed

This case study reports the kinematic effect of 2 different cricket shoes on a fast bowler who reports a history of posterior ankle joint impingement. The participant bowled 6 trials in 2 pairs of cricket shoes. The 3-dimensional kinematics of the joints of the front leg was quantified during stance phase of the delivery stride. Wearing the high-cut shoe resulted in the ankle being 7.7-degree angle more plantarflexed at initial contact compared with the low-cut shoe. Again, when wearing the high-cut shoe compared with the low-cut shoe, the ankle joint was 15.5-degree angle more adducted and the knee was 4.1-degree angle less externally rotated at initial contact. This case study identifies the bowler's preferred shoe (high-cut shoe) as a potential contributing factor to the symptoms he was experiencing. PMID:23657121

Bishop, Chris; Bartold, Simon; Thewlis, Dominic

2013-11-01

80

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

PubMed

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

Hung, C-M; Zink, R M

2014-07-01

81

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

PubMed

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

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

2007-12-01

82

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

Microsoft Academic Search

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

Scott Wilson; Kathy Martin

2011-01-01

83

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

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

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

2007-01-01

84

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

PubMed Central

Background Understanding demographic histories, such as divergence time, patterns of gene flow, and population size changes, in ecologically diverging lineages provide implications for the process and maintenance of population differentiation by ecological adaptation. This study addressed the demographic histories in two independently derived lineages of flood-resistant riparian plants and their non-riparian relatives [Ainsliaea linearis (riparian) and A. apiculata (non-riparian); A. oblonga (riparian) and A. macroclinidioides (non-riparian); Asteraceae] using an isolation-with-migration (IM) model based on variation at 10 nuclear DNA loci. Results The highest posterior probabilities of the divergence time parameters were estimated to be ca. 25,000 years ago for A. linearis and A. apiculata and ca. 9000 years ago for A. oblonga and A. macroclinidioides, although the confidence intervals of the parameters had broad ranges. The likelihood ratio tests detected evidence of historical gene flow between both riparian/non-riparian species pairs. The riparian populations showed lower levels of genetic diversity and a significant reduction in effective population sizes compared to the non-riparian populations and their ancestral populations. Conclusions This study showed the recent origins of flood-resistant riparian plants, which are remarkable examples of plant ecological adaptation. The recent divergence and genetic signatures of historical gene flow among riparian/non-riparian species implied that they underwent morphological and ecological differentiation within short evolutionary timescales and have maintained their species boundaries in the face of gene flow. Comparative analyses of adaptive divergence in two sets of riparian/non-riparian lineages suggested that strong natural selection by flooding had frequently reduced the genetic diversity and size of riparian populations through genetic drift, possibly leading to fixation of adaptive traits in riparian populations. The two sets of riparian/non-riparian lineages showed contrasting patterns of gene flow and genetic differentiation, implying that each lineage showed different degrees of reproductive isolation and that they had experienced unique evolutionary and demographic histories in the process of adaptive divergence. PMID:23273287

2012-01-01

85

Phylogeographical structure in the subterranean tuco-tuco Ctenomys talarum (Rodentia: Ctenomyidae): contrasting the demographic consequences of regional and habitat-specific histories.  

PubMed

In this work we examined the phylogeography of the South American subterranean herbivorous rodent Ctenomys talarum (Talas tuco-tuco) using mitochondrial DNA (mtDNA) control region (D-loop) sequences, and we assessed the geographical genetic structure of this species in comparison with that of subterranean Ctenomys australis, which we have shown previously to be parapatric to C. talarum and to also live in a coastal sand dune habitat. A significant apportionment of the genetic variance among regional groups indicated that putative geographical barriers, such as rivers, substantially affected the pattern of genetic structure in C. talarum. Furthermore, genetic differentiation is consistent with a simple model of isolation by distance, possibly evidencing equilibrium between gene flow and local genetic drift. In contrast, C. australis showed limited hierarchical partitioning of genetic variation and departed from an isolation-by-distance pattern. Mismatch distributions and tests of neutrality suggest contrasting histories of these two species: C. talarum appears to be characterized by demographic stability and no significant departures from neutrality, whereas C. australis has undergone a recent demographic expansion and/or departures from strict neutrality in its mtDNA. PMID:17688545

Mora, Matías S; Lessa, Enrique P; Cutrera, Ana P; Kittlein, Marcelo J; Vassallo, Aldo I

2007-08-01

86

Range-wide multilocus phylogeography of the red fox reveals ancient continental divergence, minimal genomic exchange and distinct demographic histories.  

PubMed

Widely distributed taxa provide an opportunity to compare biogeographic responses to climatic fluctuations on multiple continents and to investigate speciation. We conducted the most geographically and genomically comprehensive study to date of the red fox (Vulpes vulpes), the world's most widely distributed wild terrestrial carnivore. Analyses of 697 bp of mitochondrial sequence in ~1000 individuals suggested an ancient Middle Eastern origin for all extant red foxes and a 400 kya (SD = 139 kya) origin of the primary North American (Nearctic) clade. Demographic analyses indicated a major expansion in Eurasia during the last glaciation (~50 kya), coinciding with a previously described secondary transfer of a single matriline (Holarctic) to North America. In contrast, North American matrilines (including the transferred portion of Holarctic clade) exhibited no signatures of expansion until the end of the Pleistocene (~12 kya). Analyses of 11 autosomal loci from a subset of foxes supported the colonization time frame suggested by mtDNA (and the fossil record) but, in contrast, reflected no detectable secondary transfer, resulting in the most fundamental genomic division of red foxes at the Bering Strait. Endemic continental Y-chromosome clades further supported this pattern. Thus, intercontinental genomic exchange was overall very limited, consistent with long-term reproductive isolation since the initial colonization of North America. Based on continental divergence times in other carnivoran species pairs, our findings support a model of peripatric speciation and are consistent with the previous classification of the North American red fox as a distinct species, V. fulva. PMID:25212210

Statham, Mark J; Murdoch, James; Janecka, Jan; Aubry, Keith B; Edwards, Ceiridwen J; Soulsbury, Carl D; Berry, Oliver; Wang, Zhenghuan; Harrison, David; Pearch, Malcolm; Tomsett, Louise; Chupasko, Judith; Sacks, Benjamin N

2014-10-01

87

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

PubMed Central

Crassostrea gigas originated from the Pacific coast of Asia, but was introduced into several European countries in the early 1970s. Natural populations have now spread across the length of the western seaboard of Europe. To elucidate the demographic and selective processes at play during this rapid expansion, genome-scan analysis was performed on different populations. High diversities and low differentiation were observed overall, but significant genetic differentiation was found among newly established populations and between the newly established northern group and a nearly panmictic group composed of southern European populations and a population from Japan. Loss of genetic diversity was also seen in the north, likely caused by founder events during colonization. The few strongly supported outlier loci revealed a genetic structure uncorrelated with the north/south differentiation, but grouping two samples from the Danish fjords (northern group) and one from the Dutch Scheldt estuary (southern group) with the one from Japan. These findings might reflect the following: (i) parallel adaptation to similar environmental pressures (fjord-like environment) within each of the two groups or (ii) a footprint of a secondary introduction of an alternative genomic background maintained by multifarious isolation factors. Our results call for a closer examination of adaptive genetic structure in the area of origin. PMID:24187588

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

2013-01-01

88

Phylogeography across a continent: the evolutionary and demographic history of the North American racer (Serpentes: Colubridae: Coluber constrictor).  

PubMed

Most phylogeographic studies examine organisms that do not have transcontinental distributions and therefore the genetic and temporal effects of barriers across an entire continent cannot be assessed with respect to a single species. We examined the phylogeographic structure, lineage age, and historical demography using sequences from the mtDNA cytochrome b gene of the widespread North American racer (Coluber constrictor), one of the few abundant transcontinental snakes that occurs throughout many diverse biomes. Our results indicate that this complex is comprised of six lineages differing greatly in geographic extent, with the largest (a central US clade) being approximately 26 times greater than the smallest (a lineage restricted to the Florida Panhandle and nearby portions of adjacent States). Most of the six lineages appear to be separated at previously identified genetic barriers for several vertebrates with similar ranges. Lineage diversification in this species began in the late Miocene, separating populations in the Florida Peninsula from the remainder of the US. Diversification of lineages continued throughout the Pliocene and early Pleistocene. Four of the six lineages occur east of the Mississippi River, with only two distinctly young ( approximately 1.5 mya) lineages found west of the Mississippi River (one occurs west of Continental Divide). All methods of demographic inference, including the mismatch distribution, Fu and Li's D and Tajima's D , and Bayesian skyline plots revealed population expansion occurring in the mid-to-late Pleistocene for every lineage, regardless of size or proximity to formerly glaciated areas. Population expansion for lineages found east of the Mississippi River occurred earlier and was much greater than those found west of the River. PMID:18093846

Burbrink, Frank T; Fontanella, Frank; Alexander Pyron, R; Guiher, Timothy J; Jimenez, Cynthia

2008-04-01

89

Time history analysis of axial forces (Pass Through Forces) at joints in a braced frame  

E-print Network

As buildings keep getting taller, traditional braced lateral systems take more loads. This generates a phenomenon at every joint of a frame called "Pass Through Force". Pass through forces come from the transfer of axial ...

Paschini, Vincent

2012-01-01

90

Ancestral Polymorphisms and Sex-Biased Migration Shaped the Demographic History of Brown Bears and Polar Bears  

PubMed Central

Recent studies have reported discordant gene trees in the evolution of brown bears and polar bears. Genealogical histories are different among independent nuclear loci and between biparentally inherited autosomal DNA (aDNA) and matrilineal mitochondrial DNA (mtDNA). Based on multi-locus genomic sequences from aDNA and mtDNA, we inferred the population demography of brown and polar bears and found that brown bears have 6 times (aDNA) or more than 14 times (mtDNA) larger population sizes than polar bears and that polar bear lineage is derived from within brown bear diversity. In brown bears, the effective population size ratio of mtDNA to aDNA was at least 0.62, which deviated from the expected value of 0.25, suggesting matriarchal population due to female philopatry and male-biased migration. These results emphasize that ancestral polymorphisms and sex-biased migration may have contributed to conflicting branching patterns in brown and polar bears across aDNA genes and mtDNA. PMID:24236053

Nakagome, Shigeki; Mano, Shuhei; Hasegawa, Masami

2013-01-01

91

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.

92

Hip joint disease in psoriatic arthritis: risk factors and natural history  

PubMed Central

Patients and methods: 504 patients with PsA according to ESSG criteria were studied. Mean follow up was 5.7 years (range <1–45). Mean age at onset of psoriasis was 32 years and of PsA, 39 years. The most common pattern of PsA at onset was oligoarticular (49%) and at the latest examination, polyarticular (65%). Sacroiliitis or spondylitis was diagnosed in 94 (18.7%) patients. Results: 32 (6.3%) patients developed psoriatic hip arthropathy, and of these, 26 (81%) also had sacroiliitis or spondylitis. In 7/17 (41%) patients the hip became affected within 1 year after the onset of PsA. Hip disease occurred more often in younger patients. Sex, pattern of peripheral arthritis, duration of psoriasis before arthritis affected the distal interphalangeal joints, dactylitis, or enthesitis were not associated with the risk of hip disease. Seventeen patients were followed up and nine required hip arthroplasty. Sixteen (50%) first had arthroplasty within 5 years after the onset of hip pain. Conclusions: Psoriatic hip arthropathy occurs infrequently in PsA and is associated with earlier onset of arthritis and psoriatic spondylitis. Bilateral hip involvement and rapid progression to hip arthroplasty are common. PMID:15958761

Michet, C; Mason, T; Mazlumzadeh, M

2005-01-01

93

An assessment of the Brazos Valley Museum of Natural History's Summer Nature Camp: participant demographics, marketing, and suggestions for the future  

E-print Network

, and implemented natural history programs and special events for schools, groups, and public, induding outreach education. Administrator for Summer Safari Day camp. Served as one of five zoo managers, responsible for forty employees including animal care staff..., and implemented natural history programs and special events for schools, groups, and public, induding outreach education. Administrator for Summer Safari Day camp. Served as one of five zoo managers, responsible for forty employees including animal care staff...

Smith, Randolph S.

2012-06-07

94

Demographic life transitions: an alternative theoretical paradigm  

Microsoft Academic Search

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

Peter McDonald

1996-01-01

95

Demographic Fluctuation and Institutional Response in Sparta.  

E-print Network

??AbstractDemographic Fluctuation and Institutional Response in SpartabyTimothy Donald DoranDoctor of Philosophy in Ancient History and Mediterranean ArchaeologyUniversity of California, BerkeleyProfessor Emily Mackil, ChairThe Spartiate population… (more)

DORAN, TIMOTHY DONALD

2011-01-01

96

Population structure, demographic history, and selective processes: contrasting evidences from mitochondrial and nuclear markers in the European spiny lobster Palinurus elephas (Fabricius, 1787).  

PubMed

The European spiny lobster Palinurus elephas (Fabricius, 1787) is an ecologically and economically important species inhabiting a wide geographic range that extends from the North-east Atlantic and Azores to the Eastern Mediterranean. We investigated the population structure and evolutionary history of this species by both mitochondrial and microsatellite markers. Ten population samples covering a large part of the species distribution range (three samples from the Atlantic Ocean and seven from the Mediterranean Sea) were analyzed for a portion of the mitochondrial control region and seven polymorphic microsatellite loci. Both markers rejected the hypothesis of panmixia identifying two differentiated gene pools. The control region clearly distinguished the Atlantic and Mediterranean populations in two genetically separated groups. Microsatellites, also revealed two groups roughly associated to the Atlantic-Mediterranean separation, however, the Azores sample did not conform to this geographic scheme. Discrepancy between mitochondrial and nuclear markers emerged also when reconstructing the history of the species. Neutrality tests of the mitochondrial sequences indicated a departure from mutation-drift equilibrium that, combined to the mismatch analysis, pointed toward a sudden population expansion in both Atlantic and Mediterranean gene pools. Unexpectedly, microsatellites did not identify any signal of population expansion neither in the Atlantic pool nor in the Mediterranean one. PMID:20510378

Babbucci, Massimiliano; Buccoli, Simona; Cau, Angelo; Cannas, Rita; Goñi, Raquel; Díaz, David; Marcato, Stefania; Zane, Lorenzo; Patarnello, Tomaso

2010-09-01

97

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

E-print Network

, 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...

Godin, Jason Robert

2005-11-01

98

Undergraduate History Degrees School of History, Archaeology and Religion, Cardiff University  

E-print Network

Undergraduate History Degrees School of History, Archaeology and Religion, Cardiff University BA History BA History with Welsh History BA Integrated Degree (Archaeology & Medieval History, Ancient History & Medieval History) BA Joint Schemes (with Archaeology, Religious Studies, Languages etc.) Bsc

Davies, Christopher

99

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

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

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

2013-01-01

100

History of the Balkans: Eighteenth and Nineteenth Centuries. Volume 1. The Joint Committee on Eastern Europe Publications Series. No. 12.  

ERIC Educational Resources Information Center

Designed as an introductory history, this book covers developments in the Balkan Peninsula from the 17th through the 19th centuries. Emphasis is placed on the process by which separate nationalities broke away from imperial rule, established independent states, and embarked on economic and social modernization. To establish perspective on the role…

Jelavich, Barbara

101

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

NASA Astrophysics Data System (ADS)

We image the rupture history of the 2009 L'Aquila (central Italy) earthquake using a nonlinear joint inversion of strong motion and GPS data. This earthquake ruptured a normal fault striking along the Apennines axis and dipping to the SW. The inferred slip distribution is heterogeneous and characterized by a small, shallow slip patch located up-dip from the hypocenter (9.5 km depth) and a large, deeper patch located southeastward. The rupture velocity is larger in the up-dip than in the along-strike direction. This difference can be partially accounted by the crustal structure, which is characterized by a high velocity layer above the hypocenter and a lower velocity below. The latter velocity seems to have affected the along strike propagation since the largest slip patch is located at depths between 9 and 14 km. The imaged slip distribution correlates well with the on-fault aftershock pattern as well as with mapped surface breakages.

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

2009-10-01

102

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

PubMed

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

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

2013-12-01

103

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

PubMed Central

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

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

2014-01-01

104

Demography, Demographic Tran-sition and Demographic Policies are  

E-print Network

to use as a scapegoat: the Demography, Demographic Transition, Demographic Policies Gérard Parenthood) D #12;190 DEMOGRAPHY, DEMOGRAPHIC TRANSITION, DEMOGRAPHIC POLICIES causes of the world189 Demography, Demographic Tran- sition and Demographic Policies are concepts which have precise

Paris-Sud XI, Université de

105

Russia's Demographic "Crisis"  

NSDL National Science Digital Library

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

1996-01-01

106

The business of demographics.  

PubMed

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

Russell, C

1984-06-01

107

Streptococcus pneumoniae serotype 6C presenting as recurrent prosthetic knee joint infection in a patient with a history of congenital asplenia and underlying autoimmune disease: a case report and literature review.  

PubMed

This report describes a case of primary Streptococcus pneumoniae bacteremia with prosthetic joint infection caused by serotype 6C with recurrent infection in a patient with a history of congenital asplenia and underlying autoimmune disease. Isolates from the primary and recurrent infections were determined to be indistinguishable by pulsed-field gel electrophoresis. This study expands the conditions associated with recurrent invasive pneumococcal disease caused by serotype 6C. PMID:24139971

Roberts, Amity L; Hewlett, Angela L; Yu, Jigui; Nahm, Moon H; Fey, Paul D; Iwen, Peter C

2013-12-01

108

doi:10.1155/2012/350461 Research Article Joint Effect of Childhood Abuse and Family History of Major Depressive Disorder on Rates of PTSD in People with Personality Disorders  

E-print Network

which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. Objective. Childhood maltreatment and familial psychopathology both lead to an increased risk of the development of posttraumatic stress disorder (PTSD) in adulthood. While family history of psychopathology has traditionally been viewed as a proxy for genetic predisposition, such pathology can also contribute to a stress-laden environment for the child. Method. Analyses were conducted to evaluate the joint effect of childhood abuse and a family history of major depressive disorder (MDD) on diagnoses of PTSD and MDD in a sample of 225 adults with DSM-IV Axis II disorders. Results. Results showed that the rate of PTSD in the presence of both childhood abuse and MDD family history was almost six-fold (OR = 5.89, P =.001) higher relative to the absence of both factors. In contrast, the rate of MDD in the presence of both factors was associated with a nearly three-fold risk relative to the reference group (OR = 2.75, P =.01). Conclusions. The results from this observational study contribute to a growing understanding of predisposing factors for the development of PTSD and suggest that joint effects of family history of MDD and childhood abuse on PTSD are greater than either factor alone. 1.

Janine D. Flory; Rachel Yehuda; Vincent Passarelli; Larry J. Siever

109

Study 1: Method Demographics  

E-print Network

Study 1: Method Demographics ·346 men and 299 women · 41.1% Dating, 18.2% Cohabiting, 4.2% Engaged domains, they reported more authenticity doubts and insecurity (Study 1). When they received criticism insecurities perpetuates them. Journal of Personality and Social Psychology, 95, 420-441. Lemay, E. P., Jr

New Hampshire, University of

110

Beyond the demographic transition  

Microsoft Academic Search

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

Arthur A. Campbell

1974-01-01

111

Completing the Demographic Transition  

Microsoft Academic Search

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

John Bongaarts; Rodolfo A. Bulatao

1999-01-01

112

Changing Hispanic Demographics.  

ERIC Educational Resources Information Center

This report provides a demographic overview of Hispanics in the United States. Information was drawn largely from recent census figures. The following highlights are reported: (1) Hispanic Americans are the youngest and fastest growing minority group, but they are also more likely than non-Hispanics to drop out of school, be unemployed or…

McKay, Emily Gantz

113

Demographics of Transition Objects  

E-print Network

The unusual properties of transition objects (young stars with an optically thin inner disc surrounded by an optically thick outer disc) suggest that significant disc evolution has occured in these systems. We explore the nature of these systems by examining their demographics, specifically their stellar accretion rates (Mdot) and disc masses (Mdisc) compared to those of accreting T Tauri stars of comparable age. We find that transition objects in Taurus occupy a restricted region of the Mdot vs. Mdisc plane. Compared to non-transition single stars in Taurus, they have stellar accretion rates that are typically ~10 times lower at the same disc mass and median disc masses ~4 times larger. These properties are anticipated by several proposed planet formation theories and suggest that the formation of Jovian mass planets may play a significant role in explaining the origin of at least some transition objects. Considering transition objects as a distinct demographic group among accreting T Tauri stars leads to a ...

Najita, Joan R; Muzerolle, James

2007-01-01

114

[Peruvian demographic transition].  

PubMed

The demographic transition is conceptualized as the historic change from high to low fertility and mortality rates in a population. Peru's population was reduced by an estimated 80% as a result of new diseases, destruction of the economy, and the brutal regime of colonial exploitation after the Spanish conquest. From colonial times to the least the 1940s, Peru's principal population problem was the scarcity of manpower. The population grew at an annual rate of about .03% between 1650 and 1800, increasing to about 1.3% between 1876 and 1940. High fertility throughout the 19th century and a stabilization of mortality due to reduced incidence and deadliness of epidemics contributed to the increased growth rate. In the 1940s the process of demographic transition was initiated by abrupt declines in mortality. The crude death rate declined from 27/1000 in 1940 to 16/1000 in 1961 and 9/1000 in 1988, with the rate still declining. Fertility remained high and possibly increased slightly. The crude birth rate was estimated at 45/1000 in 1940 and 45.4/1000 in 1961. Improvements in infant and general mortality rates in developing countries like Peru result from diffusion of technological advances in prevention and control of diseases and improvement in health services rather than from changes in the economic and social structure. The 3rd phase of the demographic transition began with declines in fertility from 45.4/1000 in 1961 to 42.0/1000 in 1972 and 36.0/1000 in 1981. Despite declines, mortality and fertility continue to be elevated in Peru. The theory of demographic transition views the reduction of infant mortality, improvements in health and educational conditions and the condition of women, and more equitable income distribution as essential for a true decline in birth rates. In Peru, however, fertility has declined in a context of deteriorating living conditions and in the absence of effective family planning programs. The process of demographic transition must be accelerated, which will require improvements in education, income, and availability of sanitary services among other changes. PMID:12315513

Carbajal Chirinos, C

1988-06-01

115

[Cancer and demographic transition].  

PubMed

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

Napalkov, N P

2004-01-01

116

Demographics of transition objects  

NASA Astrophysics Data System (ADS)

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

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

2007-06-01

117

Demographics of Transition Objects  

E-print Network

The unusual properties of transition objects (young stars with an optically thin inner disc surrounded by an optically thick outer disc) suggest that significant disc evolution has occured in these systems. We explore the nature of these systems by examining their demographics, specifically their stellar accretion rates (Mdot) and disc masses (Mdisc) compared to those of accreting T Tauri stars of comparable age. We find that transition objects in Taurus occupy a restricted region of the Mdot vs. Mdisc plane. Compared to non-transition single stars in Taurus, they have stellar accretion rates that are typically ~10 times lower at the same disc mass and median disc masses ~4 times larger. These properties are anticipated by several proposed planet formation theories and suggest that the formation of Jovian mass planets may play a significant role in explaining the origin of at least some transition objects. Considering transition objects as a distinct demographic group among accreting T Tauri stars leads to a tighter relationship between disc masses and stellar accretion rates, with a slope between the two quantities that is close to the value of unity expected in simple theories of disc accretion.

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

2007-04-13

118

Demographic Trends in Social Work over a Quarter-Century in an Increasingly Female Profession  

ERIC Educational Resources Information Center

This article depicts the changing demographic portrait of social work education in the United States from 1974 through 2000 and considers the demographic shifts in the profession of social work. During this period, BSW and joint MSW-BSW programs increased from 150 to 404, MSW programs increased from 79 to 139, and social work doctoral programs…

Schilling, Robert; Morrish, Jennifer Naranjo; Liu, Gan

2008-01-01

119

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

Microsoft Academic Search

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

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

2000-01-01

120

Demographics of Planetary Science  

NASA Astrophysics Data System (ADS)

A survey was sent out to university departments around the US that were thought to include faculty involved in planetary science research and/or offer planetary science undergraduate or graduate degrees. This is Part A of a study of the demographics of planetary science carried out by the American Institute of Physics (AIP) and sponsored by NASA's Planetary Science Division. Part B will be a survey of the planetary scientists with PhDs working in the US, to be carried out by the AIP in mid-2011. Starting on December 8th 2010 surveys were sent out by email to department chairs. A total of 48 departments responded between December 9th and April 8th . There is only U of Arizona that has a department that is called planetary sciences - the rest are combined with Earth sciences (14), astronomy (15), geology/geophysics (8), physics (7), atmospheric science (5), something else or combinations thereof. We present statistics from these 48 departments on faculty, researchers, graduate and undergraduate students.

Bagenal, F.; White, S.

2011-10-01

121

Astronomy 101 Student Demographics  

NASA Astrophysics Data System (ADS)

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.

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

2001-05-01

122

Demographic change, growth and agglomeration  

Microsoft Academic Search

This article presents a framework within which the effects of demographic change on both agglomeration and growth of economic activities can be analyzed. I introduce an overlapping generation structure into a New Economic Geography model with endogenous growth due to learning spillovers and focus on the effects of demographic structures on long-run equilibrium outcomes and stability properties. First, life-time uncertainty

Theresa Grafeneder-Weissteiner

2010-01-01

123

Art History MA (Single Honours Degree)  

E-print Network

usually focuses on the histories of the so-called `major arts'(painting, sculpture and architecture; the art of Eastern Europe; the history of Scottish art, architecture and design; the history56 Art History MA (Single Honours Degree) Art History MA (Joint Honours Degrees) Art History

Brierley, Andrew

124

[Demographic profile of Venezuela].  

PubMed

Sources of demographic data for Venezuela include 11 population censuses conducted between 1873-1981, birth and death registration statistics, and the household sample survey. The average annual rate of population growth increase from 2.8% between 1920-40 to 3-4% thereafter. The population at the 1961 census was 7.52 million. According to preliminary data from the 1981 census, the population of 14.57 million is growing at an annual rate of 2.8%. 41.2% of the population is under 15 years old, implying a huge demand for educational and health services, housing and employment. The dependency rate in 1980 was 81.3% for the country as a whole, 100.4% in rural areas, and 76.0% in urban areas. The young age structure means that the population will continue to grow even if natality rates decline. The crude natality rate was estimated at 47.3/1000 for 1950-55, 36.0 for 1970-75, and 32.9 for 1980-85. Some rural areas still have natality rates of over 47/1000. The total fertility rate declined from 6.5 in 1950-55 to 4.1 in 1980-85. The decline in the natality rate reflects improving quality of life, availability of family planning services, urbanization, and access of women to productive activities and educational centers. The mortality rate was 12.3/1000 in 1950-55, 9.1 in 1960-65, in 1970-75, and has been estimated at 5.5 for 1980-85. Some rural areas have mortality rates of 8.1. The infant mortality rate was 50.2/1000 in 1971 and 34.3 in 1980. Life expectancy at birth is about 69 years. During the 1920s, Venezuela unerwent expansion in infrastructure and technological utilization, generating rapid urbanization. 39.2% of the population was urban in 1941, compared to 78.8% in 1980. The significance of urbanization in Venezuela is due to the rapidity as well as the diffusion of the process. The household sample survey for the 2nd half of 1980 indicated a total of 8.16 million employed and an activity rate of 32.1% overall, 46.4% for males and 17.7% for females. The demographic situation of Venezuela does not appear alarming if viewed in isolation, but the deficit of some 500,000 housing units, the million unemployed, the importation of about 75% of the country's food, the stagnation of agriculture, the lower than subsistence level of about 40% of incomes, and the lack of population policies suggest that the 24.7 million inhabitants projected for 2000 will pose a considerable challenge to the nation. PMID:12266336

Quintero, I

1984-04-01

125

DEMOGRAPHIC FACTORS IN THE INTEGRATION OF THE NEGRO.  

ERIC Educational Resources Information Center

DEMOGRAPHIC FACTORS HAVE HAD NEGATIVE RATHER THAN POSITIVE EFFECTS ON INTEGRATION (DEFINED HERE AS A KIND OF ACCULTURATION). THE POPULATION HISTORY OF THE NEGRO INDICATES THAT (1) SINCE 1910 THE NEGRO POPULATION HAS GROWN ENORMOUSLY, (2) NEGROES HAVE BEEN REDISTRIBUTED INTO THE NORTHERN AND WESTERN URBAN AREAS, (3) THEY HAVE REMAINED LARGELY IN…

HAUSER, PHILIP M.

126

Demographic Data in Community Assessment  

NSDL National Science Digital Library

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.

Goldberg, Shari

127

Demographics and the Rural Ethos.  

ERIC Educational Resources Information Center

Describes the meaning of "rural" and identifies 31 states having a significant rural character. Discusses certain generalizations about rural America. Provides a demographic analysis with school finance implications. Draws implications for rural school finance policy. (Contains 3 tables.)(PKP)

Ward, James G.

2003-01-01

128

Joint Occupancy.  

ERIC Educational Resources Information Center

This annotated bibliography includes summaries of 15 articles and reports dealing with the joint use of buildings and facilities by schools and other public or private organizations. An introductory section describes the historical origins and development of the joint occupancy concept and examines the various economic and philosophical arguments…

Higham, Charlene Ellison

129

Ceramic joints  

DOEpatents

Butt joints between materials having different coefficients of thermal expansion are prepared having a reduced probability of failure of stress facture. This is accomplished by narrowing/tapering the material having the lower coefficient of thermal expansion in a direction away from the joint interface and not joining the narrow-tapered surface to the material having the higher coefficient of thermal expansion.

Miller, Bradley J. (Worcester, MA); Patten, Jr., Donald O. (Sterling, MA)

1991-01-01

130

ORIGINAL PAPER Bird demographic responses to predator removal programs  

E-print Network

Abstract Invasive predators pose a significant risk to bird populations worldwide. Humans have a long history of removing predators from ecosystems; current island restoration actions typically focus on the removal of invasive predators, such as non-native rodents, from seabird breeding islands. While not overly abundant, the results of predator removal studies provide valuable information on the demographic response of birds, and can assist conservation practitioners with prioritizing invasive predator removal projects. We review such studies focusing on observed demographic responses of bird populations to predator removal campaigns and whether ecological factors are useful in predicting those responses. From the 800? predator removal programs indentified, a small fraction (n = 112) reported

C. Josh Donlan; J. L. Lavers; C. Wilcox; C. Josh Donlan; C. Josh Donlan

131

NIDI: Netherlands Interdisciplinary Demographic Institute  

NSDL National Science Digital Library

NIDI is an independent institute engaged in the scientific study of population. Research carried out at NIDI aims to contribute to the description, analysis, explanation or prediction of demographic trends in the past, the present and the future. The NIDI site offers several items of interest to Demographers and graduate students. Users can consult a list of projects the Institute is currently sponsoring, with some links to abstracts and contact information; the site also contains information on a number of NIDI's publications including Institute reports, European Studies of Population, and the Dutch language journals DEMOS and Bevolking en Gezin (Population and Family). Lists of articles and English abstracts are available for all publications, as is a comprehensive annotated list of related links, including a number of links to sites with Demographic software.

1998-01-01

132

Undergraduate Archaeology Degrees School of History, Archaeology and Religion, Cardiff University  

E-print Network

Undergraduate Archaeology Degrees School of History, Archaeology and Religion, Cardiff University BA Archaeology BSc Archaeology BA Integrated Degree Archaeology and Ancient History BA Joint Schemes (With History, Medieval History, Languages etc.) #12;SCHOOL OF HISTORY, ARCHAEOLOGY AND RELIGION

Davies, Christopher

133

Demographic disaster: death/birth gap widens.  

PubMed

This article summarizes papers presented at a conference on the worsening of the demographic situation in Russia held in July, 1994. They find that "during 1993 alone the average life expectancy of men and women in the country decreased by 3.6 [to 59 years] and 2 years [to 72 years], respectively, and the difference between them for this index reached 13 years--for modern history, an unprecedented occurrence in peace time." It is also noted that the birth rate has declined significantly, mortality from injuries and poisoning has greatly increased, and the morbidity situation deteriorated. The article concludes that the total population is likely to fall by 9 million by the year 2005. PMID:12287854

Baiduzhy, A

1994-08-10

134

[The demographic situation in Italy].  

PubMed

The author discusses demographic trends in Italy during the 1970s. Information is included on population growth; sex and age structure; marriages, separations, and divorces; natality and fertility; abortions; general, infant, and perinatal mortality; mortality by age and cause; internal migration and urbanization; and international migration (SUMMARY IN ENG, FRE) PMID:12338329

Lenzi, R

1980-01-01

135

Demographic Trends in Nonmetropolitan America.  

ERIC Educational Resources Information Center

Reviews nonmetropolitan regional demographic trends of the 1980s including population change, age distribution, migration by county type and age, effect of metropolitan proximity, changes in income and poverty, minority population, educational attainment, numbers of rural schools and school districts, and district enrollment. Suggests that…

Hobbs, Daryl

1994-01-01

136

Inferring Demographic History from a Spectrum of Shared Haplotype Lengths  

E-print Network

trio parents from the 1000 Genomes project. The data show evidence of extensive gene flow between into Europe are both necessary to explain the spectrum of IBS sharing in the trios, rejecting simpler models

Nielsen, Rasmus

137

ORIGINAL ARTICLE Life history and demographic determinants of  

E-print Network

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

Bernatchez, Louis

138

ORIGINAL ARTICLE Life history and demographic determinants of  

E-print Network

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

Bernatchez, Louis

139

ORIGINAL ARTICLE Speciation and demographic history of Atlantic eels  

E-print Network

Convergence Zone) (Tesch, 2003; van Ginneken and Maes, 2005). There is considerable overlap between their spawning regions, but with a clear dominance of American eels in the West and European eel in the East (Mc

Bernatchez, Louis

140

Gabrielle Hecht Department of History  

E-print Network

in Anthropology and History, 1999-present · Associate Professor (joint appointment), Residential Cold War, editor (MIT Press, 2011). #12;2 The Radiance of France: Nuclear Power & essays "On the Fallacies of Cold War Nostalgia: Capitalism, Colonialism

Edwards, Paul N.

141

Is joint hypermobility important in prepubertal children?  

Microsoft Academic Search

The purpose of this study was to investigate serum prolidase activity and its relationship with collagen metabolism and joint\\u000a hypermobility, and to determine the prevalence and characteristics of joint hypermobility in prepubertal children. Serum prolidase\\u000a activity was measured spectrophotometrically. Joint hypermobility was defined using Beighton criteria. The children underwent\\u000a complete history and physical examination. Serum levels of prolidase were lower

Pelin Yazgan; ?clal Geyikli; Dost Zeyrek; Lutfu Baktiroglu; Mehmet Ali Kurcer

2008-01-01

142

Joint hypermobility  

Microsoft Academic Search

Joint hypermobility is an area of neglect in rheumatology. That is not to say it is overlooked by rheumatologists. It is spotted when sought, but for many unfortunate patients, here the story ends. The act of recognition becomes the goal in itself rather than the medium through which effective therapy can be provided. This chapter serves to reinforce the clinical

Rodney Grahame

2003-01-01

143

Degenerative Joint Disease in Female Ballet Dancers  

Microsoft Academic Search

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

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

1995-01-01

144

The California Latino Demographic Databook  

NSDL National Science Digital Library

Posted by the University of California-Berkeley's principal archive for social science statistics, this Website features selected data from The California Policy Research Center's publication, The California Latino Demographic Databook. The data are presented in the form of figures, tables, and demographic maps and cover such topics as the racial/ ethnic composition of California's population; percentages of Hispanics in California, county by county; Immigrants Admitted as Permanent California Residents from Selected Countries; Size of Hispanic and Non-Hispanic Households by Nativity, Period of Entry, and Citizenship; Percent of Californians in Selected Occupations by Detailed Origin; and much more. The entire databook can be ordered from the California Policy Research Center through a link on the Website.

145

War and the demographic trap.  

PubMed

Advice is offered on alleviating environmental damage and the suffering of women and children from the effects of war. It is postured that the demographic trap, which was described by King and Elliott, is responsible for environmental stress and many wars. The surface cause may be identified as ideology, politics, or ethnicity, but as in the case of Bosnia, the "ethnic cleansing" makes farmland available to sustain expanding Serbian or Croatian populations. If the land is environmentally damaged by war, then there is little hope of sustainable development. Conflicts in many countries have driven people to urban areas or periurban slums because of displacement and the failure of subsistence economics. Mortality from wars has reached more than a 100 million since the early 1990s. A comparable number have died indirectly from famine and disease associated with the disruption of agriculture and infrastructure from wars. Since 1945, 66-75% of mortality victims have been civilians, of whom 15 million have been women and children. In 1993, there were at least 30 conflicts ongoing throughout the world. Not all of these conflicts are as "ferocious" as the Bosnian conflict, but these "so called low intensity wars" nonetheless disrupt and kill. The manifestations of the demographic trap can be alleviated through interventions that focus on multisectoral aid and conflict resolution. There must be a cooperative effort on the part of health workers, agricultural scientists, mediators, and development personnel. Unfortunately, the amount of development assistance from Europe and America has been reduced in recent years. The recession has affected the provision of international aid. African nations, in particular, have been affected, yet these countries remain the neediest in the world. It would appear that aid agencies have given up hope that the demographic trap can be closed. Population growth must be limited, as the only hope for relieving environmental stress, ecological collapse, and demographic entrapment. The challenge of reducing population must be recognized, and has been recognized by the Union of Concerned Scientists. PMID:8102662

Last, J M

1993-08-28

146

Men in the demographic transition  

Microsoft Academic Search

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

Bobbi S. Low

1994-01-01

147

Explaining the Neolithic Demographic Transition  

Microsoft Academic Search

Three main questions are raised in this chapter.\\u000a \\u000a 1. The part of the signal of the NDT which is demographically identifiable, based on the proportion of the immature skeletons\\u000a in cemeteries, shows that a baby-boom occurred and, beyond that, with the onset of the change in the economic system, a fertility\\u000a transition towards high values also occurred. What was the

Jean-Pierre Bocquet-Appel

148

Lurker demographics: counting the silent  

Microsoft Academic Search

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

Blair Nonnecke; Jennifer Preece

2000-01-01

149

LAW, HISTORY, &LAW, HISTORY, &LAW, HISTORY, & CULTURECULTURECULTURE  

E-print Network

LAW, HISTORY, &LAW, HISTORY, &LAW, HISTORY, & CULTURECULTURECULTURE The Law, History, and Culture specific legal issues through a humanistic lens. Opportunities for Students Phi Alpha Theta: This history honor society seeks to bring students, teachers, and writers of history together for intellectual

Rohs, Remo

150

Signals of demographic expansion in Drosophila virilis  

PubMed Central

Background The pattern of genetic variation within and among populations of a species is strongly affected by its phylogeographic history. Analyses based on putatively neutral markers provide data from which past events, such as population expansions and colonizations, can be inferred. Drosophila virilis is a cosmopolitan species belonging to the virilis group, where divergence times between different phylads go back to the early Miocene. We analysed mitochondrial DNA sequence variation among 35 Drosophila virilis strains covering the species' range in order to detect demographic events that could be used to understand the present characteristics of the species, as well as its differences from other members of the group. Results Drosophila virilis showed very low nucleotide diversity with haplotypes distributed in a star-like network, consistent with a recent world-wide exponential expansion possibly associated either with domestication or post-glacial colonization. All analyses point towards a rapid population expansion. Coalescence models support this interpretation. The central haplotype in the network, which could be interpreted as ancestral, is widely distributed and gives no information about the geographical origin of the population expansion. The species showed no geographic structure in the distribution of mitochondrial haplotypes, in contrast to results of a recent microsatellite-based analysis. Conclusion The lack of geographic structure and the star-like topology depicted by the D. virilis haplotypes indicate a pattern of global demographic expansion, probably related to human movements, although this interpretation cannot be distinguished from a selective sweep in the mitochondrial DNA until nuclear sequence data become available. The particular behavioural traits of this species, including weak species-discrimination and intraspecific mate choice exercised by the females, can be understood from this perspective. PMID:18298823

2008-01-01

151

Joint Replacement (Finger and Wrist Joints)  

MedlinePLUS

... A-Z Hand Anatomy Find a Hand Surgeon Joint Replacement Email to a friend * required fields From * To * ... be possible to treat arthritic joints surgically, including “joint replacement” procedures. What does it mean to have a “ ...

152

Our Demographically Divided World, Worldwatch Paper 74.  

ERIC Educational Resources Information Center

Existing demographic analyses do not explain the negative relationship between population growth and life-support systems that are now emerging in scores of developing countries. The demographic transition, a theory first outlined by demographer Frank Notestein in 1945, classified all societies into one of three stages. Drawing heavily on the…

Brown, Lester R.; Jacobson, Jodi L.

153

Joint hypermobility.  

PubMed

Joint hypermobility is an area of neglect in rheumatology. That is not to say it is overlooked by rheumatologists. It is spotted when sought, but for many unfortunate patients, here the story ends. The act of recognition becomes the goal in itself rather than the medium through which effective therapy can be provided. This chapter serves to reinforce the clinical and epidemiological importance of a common disorder whose significance is under-appreciated and impact largely ignored. In contradistinction to our earlier chapter, published in 2000, which took for its remit the heritable disorders of connective tissue in general, the current one focuses on the commonly encountered (so-called benign) joint hypermobility syndrome, its recognition, epidemiology, clinical features and management according to the most recent literature. PMID:15123047

Hakim, Alan; Grahame, Rodney

2003-12-01

154

Demographic estimation methods for plants with dormancy  

USGS Publications Warehouse

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

Kery, M.; Gregg, K. B.

2004-01-01

155

vol. 29, no. 5 the american naturalist september 1999 The Demographic Cost of Reproduction and Its Consequences  

E-print Network

and a permutation test to detect growth costs of reproduction and show how these translate into demographic costsvol. 29, no. 5 the american naturalist september 1999 The Demographic Cost of Reproduction and Its 5, 1998; Accepted April 16, 1999 abstract: It is an axiom of life-history theory that reproduction

Silvertown, Jonathan

156

Demographic Information Provide school name, address, and ACT/CEEB code; include web address, counselor(s) name, address,  

E-print Network

demographics (e.g. % ESL, free lunch, special education, on aid, etc.). An overview can include history-specific requirements. e.g, "All graduates are required to take two terms of fine arts." "Students must do 100 hours

157

Anticipated* new joint B.A. programs  

E-print Network

literature course ! One course in Spanish linguistics: o CAS LS 504 History of Spanish ! One additional CAS in Japanese linguistics, selected from: o CAS LJ 410 History of the Japanese Language o CAS LJ 510 StructureAnticipated* new joint B.A. programs combining the study of LINGUISTICS with the study of LANGUAGE

Finzi, Adrien

158

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

PubMed

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

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

2013-12-01

159

Racial Disparities in Receipt of Hip and Knee Joint Replacements Are Not Explained by Need: The Health and Retirement Study 1998-2004  

Microsoft Academic Search

Background. Hip and knee joint replacement rates vary by demographic group. This article describes the epidemiology of need for joint replacement, and of subsequent receipt of a joint replacement by those in need. Methods. Data from the Health and Retirement Study were used to assess need for hip or knee joint replacement in a total of 14,807 adults aged 60

Nicholas Steel; Allan Clark; Iain A. Lang; Robert B. Wallace; David Melzer

2008-01-01

160

Social security and demographic shocks.  

PubMed

This paper examines the sharing of risks between generations in the framework of an overlapping generations model of social security with shocks to the productivity of labor and capital and demographic shocks. The study focused on stationary long run allocations. The concept of interim optimality was utilized, which amounts to standard Pareto optimality once the state of the world in which the agents are born is known. The set of interim optimal allocations was characterized and the equilibria associated with various institutional forms of social security from the point of view of the optimal criterion were also studied. In addition, the analogs of two traditional welfare theorems of microeconomic theory were obtained. PMID:12295295

Demange, G; Laroque, G

1999-05-01

161

Do demographics affect marital satisfaction?  

PubMed

This study examined the effects of age, education, number of children, employment status, and length of marriage on marital satisfaction. Seven hundred and eighty-seven nonrandomly selected married adults from the Flanders region in Belgium completed the Maudsley Marital Questionnaire (MMQ) (Arrindell, Boelens, & Lambert, 1983a). The results indicated a statistically significant difference between the marital satisfaction of the first married and remarried adults. A gender-level analysis showed a statistically significant difference between the marital satisfaction of men and women. Among the demographic variables, the effect of length of marriage was highly significant with marital satisfaction. In a separate analysis, we found that the effect of age and number of children had a statistically significant effect on the sexual adjustment of the respondents. Accordingly, we found that age, number of children, and length of marriage were significantly positively correlated with sexual adjustment (MMQ-S) and educational attainment with general-life adjustment (MMQ-GL) problems. PMID:17162490

Jose, Orathinkal; Alfons, Vansteenwegen

2007-01-01

162

Joint Sealants for Horizontal Pavement Joints—Specifically Bridge Joints  

Microsoft Academic Search

The various types of materials that have been used to seal bridge joints have been reviewed. Some of the bridge engineers joint material requirements have been listed together with the advantages and disadvantages of the three most widely used bridge joint sealants being specified and used today. It is felt that the cold applied two component asphalt-modified polyurethane sealants come

Thomas J. Green

1969-01-01

163

Demographical and Clinical Characteristics of Behcet's Disease in Southeastern Turkey  

PubMed Central

Background We aimed to determine the demographic and clinical features of patients with Behcet’s disease (BD) in Southeastern Turkey. Methods In this study, files of 132 patients with BD (76 females and 56 males) who were diagnosed with BD according to the International Study Group criteria at the Department of Dermatology of Dicle University Faculty of Medicine from 2005 to 2009 were evaluated retrospectively. Demographical and clinical characteristics of the cases were recorded. Results Mean age of the cases was 32.40 ± 9.4 years (range 15 - 59 years) and male/female ratio was 0.73. The mean age at diagnosis was 28.71 ± 9.1 years. Six cases were diagnosed as juvenile BD (4.45%). Oral aphthous lesions (100%) and genital ulcers (94%) were found to be the most common findings of the disease, followed by pathergy positivity (75%), papulopustular lesions (74.2%), erythema nodosum (43.2%), thrombophlebitis (6.8%) and extragenital ulcers (6.1%). Systemic involvement was noted as joint involvement in 79.5%, ocular involvement in 28.8%, vascular involvement in 9.8%, pulmonary involvement in 2.3%, neurologic involvement in 2.3% and genitourinary system involvement in 0.8%. There was no significant difference between mucocutaneous findings and systemic involvement ratios of male and female cases. Conclusion Demographic and clinical features of BD may vary according to geographical region, gender and ethnicity. We hope that this study will contribute to the epidemiologic data of BD which may exhibit different clinical and demographic features in different parts of the world. PMID:25247023

Sula, Bilal; Batmaz, Ibrahim; Ucmak, Derya; Yolbas, Ilyas; Akdeniz, Sedat

2014-01-01

164

Art History 95 Art History  

E-print Network

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

Richards-Kortum, Rebecca

165

Demographic studies of extrasolar planets  

NASA Astrophysics Data System (ADS)

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

Morton, Timothy

166

Poweshiek History Preservation Project  

NSDL National Science Digital Library

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

167

Intellectual History, Social History, Cultural History… and Our History  

Microsoft Academic Search

This essay explores the links among intellectual history, social history and cultural history. It suggests that the recent turn in American historiography to cultural history is vitally important for communication studies because communication has now been thrust to center stage in virtually every subfield of history. But it warns that communication historians should not rashly and heedlessly jump into cultural

David Paul Nord

1990-01-01

168

The U.S. Demographic Transition  

Microsoft Academic Search

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

Jeremy Greenwood; Ananth Seshadri

2002-01-01

169

Demographic Influence on Annual Down Syndrome Births.  

National Technical Information Service (NTIS)

The principal objectives of the study were to: (1) help clarify the continuing role U.S. demographic changes are playing in determining the incidence and number of Down's Syndrome (DS) live births, and (2) develop a demographic model which projects for th...

C. A. Huether

1982-01-01

170

Life Potential as a Basic Demographic Indicator  

ERIC Educational Resources Information Center

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

Goerlich, Francisco J.; Soler, Angel

2013-01-01

171

Kinship based demographic simulation of societal processes  

Microsoft Academic Search

The social boundaries of small scale human societies are defined through culturally defined kin relations that transcend the specifics of the genealogical relationships produced through procreation. Kinship knowledge is culturally defined, distributed knowledge that provides structure for the persons produced through demographic processes. However, the interplay between the demographic system and the cultural system has been difficult to model. Genealogical

Dwight W. Read

1998-01-01

172

Inferring Demographic Attributes of Anonymous Internet Users  

Microsoft Academic Search

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

Dan Murray; Kevan Durrell

2000-01-01

173

Spacesuit mobility joints  

NASA Technical Reports Server (NTRS)

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

Vykukal, H. C. (inventor)

1978-01-01

174

Spacesuit mobility knee joints  

NASA Technical Reports Server (NTRS)

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

Vykukal, H. C. (inventor)

1979-01-01

175

[The ecological limits to demographic growth].  

PubMed

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

Raffestin, C

1989-09-01

176

The epidemiology and demographics of hip dysplasia.  

PubMed

The etiology of developmental dysplasia of the hip (DDH) is unknown. There are many insights, however, from epidemiologic/demographic information. A systematic medical literature review regarding DDH was performed. There is a predominance of left-sided (64.0%) and unilateral disease (63.4%). The incidence per 1000 live births ranges from 0.06 in Africans in Africa to 76.1 in Native Americans. There is significant variability in incidence within each racial group by geographic location. The incidence of clinical neonatal hip instability at birth ranges from 0.4 in Africans to 61.7 in Polish Caucasians. Predictors of DDH are breech presentation, positive family history, and gender (female). Children born premature, with low birth weights, or to multifetal pregnancies are somewhat protected from DDH. Certain HLA A, B, and D types demonstrate an increase in DDH. Chromosome 17q21 is strongly associated with DDH. Ligamentous laxity and abnormalities in collagen metabolism, estrogen metabolism, and pregnancy-associated pelvic instability are well-described associations with DDH. Many studies demonstrate an increase of DDH in the winter, both in the northern and southern hemispheres. Swaddling is strongly associated with DDH. Amniocentesis, premature labor, and massive radiation exposure may increase the risk of DDH. Associated conditions are congenital muscular torticollis and congenital foot deformities. The opposite hip is frequently abnormal when using rigorous radiographic assessments. The role of acetabular dysplasia and adult hip osteoarthritis is complex. Archeological studies demonstrate that the epidemiology of DDH may be changing. PMID:24977057

Loder, Randall T; Skopelja, Elaine N

2011-01-01

177

Darwinian and demographic forces affecting human protein coding genes  

PubMed Central

Past demographic changes can produce distortions in patterns of genetic variation that can mimic the appearance of natural selection unless the demographic effects are explicitly removed. Here we fit a detailed model of human demography that incorporates divergence, migration, admixture, and changes in population size to directly sequenced data from 13,400 protein coding genes from 20 European-American and 19 African-American individuals. Based on this demographic model, we use several new and established statistical methods for identifying genes with extreme patterns of polymorphism likely to be caused by Darwinian selection, providing the first genome-wide analysis of allele frequency distributions in humans based on directly sequenced data. The tests are based on observations of excesses of high frequency–derived alleles, excesses of low frequency–derived alleles, and excesses of differences in allele frequencies between populations. We detect numerous new genes with strong evidence of selection, including a number of genes related to psychiatric and other diseases. We also show that microRNA controlled genes evolve under extremely high constraints and are more likely to undergo negative selection than other genes. Furthermore, we show that genes involved in muscle development have been subject to positive selection during recent human history. In accordance with previous studies, we find evidence for negative selection against mutations in genes associated with Mendelian disease and positive selection acting on genes associated with several complex diseases. PMID:19279335

Nielsen, Rasmus; Hubisz, Melissa J.; Hellmann, Ines; Torgerson, Dara; Andres, Aida M.; Albrechtsen, Anders; Gutenkunst, Ryan; Adams, Mark D.; Cargill, Michele; Boyko, Adam; Indap, Amit; Bustamante, Carlos D.; Clark, Andrew G.

2009-01-01

178

Current Biology 23, 16, May 20, 2013 2013 Elsevier Ltd All rights reserved http://dx.doi.org/10.1016/j.cub.2013.04.006 The Demographic Transition Influences  

E-print Network

.1016/j.cub.2013.04.006 Report The Demographic Transition Influences Variance in Fitness and Selection Recent human history is marked by demographic transitions characterized by declines in mortality of women in rural Gambia from 1956­2010 [3]. We show how the demographic transition influenced directional

Lummaa, Virpi

179

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

PubMed Central

Background Sacroiliac (SI) joint pain is an under diagnosed source of low back pain due in part to lack of visible pathology on radiographs and symptoms mimicking other back-related disorders. Open SI joint fusion has been performed since the 1920s. This technique has fallen out of favor with the introduction of minimally invasive options. To date there has been no direct comparison between open and MIS SI joint fusion. Methods We conducted a multi-center, retrospective comparative cohort study of patients who underwent SI joint fusion using either an open surgical (OS) technique using a combination of screws and cages or a minimally invasive surgical (MIS) technique with a series of titanium plasma spray (TPS) coated triangular implants. Operative measures including surgical operating time, length of hospitalization and estimated blood loss (EBL) were collected along with demographics and medical history, surgical complications, and 12- and 24-month pain scores. Improvements in pain were compared after matching for age and gender and controlling for a history of lumbar spine fusion using repeated measures analysis of variance. Results Data were available for 263 patients treated by 7 surgeons; 149 patients treated with OS and 114 treated with MIS SI joint fusion. Compared to OS patients, MIS patients were on average 10 years older (mean age 57 vs. 46) and 69% of all patients were female. MIS operative measures of EBL, operating time and length of hospitalization were significantly lower than open surgery (p?history of prior lumbar spinal fusion, postoperative pain scores were on average 3.0 points (95% CI 2.1 – 4.0) lower in MIS vs. OS (rANOVA p?joint fusion showed postoperative improvements in pain score. Compared to OS patients, patients who underwent MIS SI joint fusion had significantly greater pain relief and more favorable perioperative surgical measures. PMID:24172188

2013-01-01

180

Prevalence and Demographic Distribution of Adult Survivors of Child Abuse in Japan.  

PubMed

A cross-sectional study was conducted with a national epidemiological survey to investigate the prevalence and demographic distribution of adult survivors of child abuse in Japan. A self-administered questionnaire was used to measure the history of child abuse and the demographic characteristics. The participants reported the following 4 types of child abuse: physical abuse (3%), sexual abuse (0.6%), neglect (0.8%), and psychological abuse (4%). Significant unequal distribution of child abuse was found to be associated with sex, living region, marital status, job status, and educational status. We determined the prevalence of adult survivors of child abuse in Japan and found that their demographic characteristics were unequally distributed. Policy makers and public health providers should take these demographic disparities into account in considering effective public health interventions for survivors of child abuse. PMID:23687257

Tsuboi, Satoshi; Yoshida, Honami; Ae, Ryusuke; Kojo, Takao; Nakamura, Yosikazu; Kitamura, Kunio

2013-05-16

181

Degenerative joint disease in female ballet dancers.  

PubMed

The relationship between long-term ballet dancing and eventual arthrosis of the hip, ankle, subtalar, and first metatarsophalangeal joint was examined in 19 former professional female dancers, aged 50 to 70 years. The dancers were compared with pair-matched controls. All 38 women underwent medical history taking, clinical examination, and roentgenography of the joints studied. The roentgenographs were independently judged by two investigators and grouped according to a modified classification of Hermodsson. We found a statistically significant increase in roentgenologic arthrosis of the ankle, subtalar, and first metatarsophalangeal joints in the ballet group compared with the control group. There was no significant difference regarding degenerative changes of the hip joint. However, subjects in the dance group who had evidence of degenerative changes on roentgenographs had no clinical complaints. There was a statistically significant increase in hallux valgus deformity in the ballet group (P < 0.05). The dancers also showed a statistically significant increase in flexion, external rotation, and abduction of the hip joint, dorsal flexion of the first metatarsophalangeal joint, and inversion and eversion of subtalar joint. But the control group had statistically significant increased plantar flexion of the first metatarsophalangeal joint. The most important cause of the statistically significant increase of arthrosis of the ankle and first metatarsophalangeal joints must be explained by repetitive microtrauma. PMID:7661255

van Dijk, C N; Lim, L S; Poortman, A; Strübbe, E H; Marti, R K

1995-01-01

182

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

National Technical Information Service (NTIS)

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

2008-01-01

183

The Dundee University Scottish Keratoconus study: demographics, corneal signs, associated diseases, and eye rubbing  

Microsoft Academic Search

AimTo investigate and correlate the corneal, refractive, topographic and familial characteristics of a large cohort with keratoconus.MethodsProspective observational study of 200 consecutive patients presenting with keratoconus during the 4 year-period 1997–2000. Subjects were examined at enrolment and at a final review. Data were collected on demographic characteristics, referral route, symptoms, refractive correction, eye rubbing, family history, medical history, slit-lamp biomicroscopic

K H Weed; C J MacEwen; T Giles; J Low; C N J McGhee

2008-01-01

184

[Demographic projections for Latin American countries prepared by CELADE].  

PubMed

The CELADE (Centro Latinoamericano de Demografia) prepares population projections for 20 Latin American countries, a difficult task considering the lack of reliable census data on births, deaths, and other demographic information. Nevertheless, the demographic situation can be estimated by distinguishing two states in the process: estimating past and present population history and formulating hypotheses regarding the future trends of demographic variables. In a typical situation for most Latin American countries, the first stage is the most difficult; results are mostly approximations of the reality. Thus, projections based on these data are unreliable. The present demographic situation in Latin America was analyzed by estimating fertility, mortality and international migration. Fertility rate was calculated based on the following data: number of children born to the female population, number of live births during the year prior to the census classified according to mother's age and number of children registered according to age up to 10 or 15 years of age. Fertility was thus calculated within 5 years prior to the census. Mortality was roughly estimated by calculating the annual death distribution by age. This promoted questions relating to orphans and the relative number of children who survived out of total number of children born to a woman. Little data was available on migration due to lack of registries on annual migration. It was estimated based on the number of people who left the country for 5 years, and promoted questions such as which country is one native of and year of entry into the country. The most important task relating to population projection of Latin America is the improvement of knowledge on fertility, mortality and migration. PMID:12335526

Somoza, J L

1978-04-01

185

The Demographic Cost of Reproduction and Its Consequences in Balsam Fir ( Abies balsamea )  

Microsoft Academic Search

It is an axiom of life-history theory that reproduction involves age-specific costs in terms of survival or future reproduction. The measurement of costs of reproduction in plants is difficult, and few field studies have measured these costs in terms of fitness or demographic components, thus creating a hiatus between theory and data. In this article, we describe methods for overcoming

Jonathan Silvertown; Mike Dodd

1999-01-01

186

Demographic analysis as an aid in shark stock assessment and management  

Microsoft Academic Search

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

Enric Cortés

1998-01-01

187

Due Diligence for Students - Geoscience Skills and Demographic Data for Career Planning  

Microsoft Academic Search

A major focus of the American Geological Institute's Human Resources program has been providing demographic and employment data so that students and mentors can better understand the dynamics of a career in the geosciences. AGI has a long history of collecting these data for the geoscience community, including 46 years of geoscience enrollments, periodic comprehensive surveys of employment in the

C. M. Keane

2001-01-01

188

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

ERIC Educational Resources Information Center

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

Handy, Ty J.

2008-01-01

189

Proprioception and joint stability  

Microsoft Academic Search

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

J. Jerosch; M. Prymka

1996-01-01

190

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

PubMed

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

Bourcier De Carbon, P

1998-01-01

191

Demographic Change and Conflict in Contemporary Africa  

Microsoft Academic Search

Sub-Saharan Africa has gone from having a very low population density and negative population growth in the 19th century to an extremely high population growth today. While some political demographers have linked the continent\\

Elliott D. Green

2009-01-01

192

Demographic and Health Survey 2000: Egypt.  

National Technical Information Service (NTIS)

The 2000 Egypt Demographic and Health Survey is the latest round of a series of surveys carried out in Egypt that have provided information on fertility behavior and its determinants, particularly contraceptive use. The EDHS findings are important in moni...

A. A. Way, F. El-Zanaty

2001-01-01

193

Inferring the Strength of Selection in Drosophila under Complex Demographic Models  

PubMed Central

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

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

2009-01-01

194

Australians' organic food beliefs, demographics and values  

Microsoft Academic Search

Purpose – To examine consumers' beliefs about organic foods and their relationship with socio-demographics and self-transcendence (universal, benevolence) personal values. Design\\/methodology\\/approach – A random questionnaire-based mail survey of 500 Australian (Victorian) adults (58 per cent response) was used. The questionnaire included items on organic food beliefs, the importance of self-transcendence values as guiding principles in life, and socio-demographics. Statistical analyses

Emma Lea; Tony Worsley

2005-01-01

195

Demographic Cycles, Cohort Size, and Earnings  

Microsoft Academic Search

This article examines whether position in the demographic cycle is an important factor in determining earnings and earnings\\u000a growth. Earnings equations for white males are estimated by using March Current Population Survey data. Position in the demographic\\u000a cycle is captured by including both measures of own cohort size and the size of surrounding cohorts in the estimated earnings\\u000a equations. Position

Mark C. Berger

1989-01-01

196

Comparing simple quasar demographics models  

NASA Astrophysics Data System (ADS)

This paper explores several simple model variations for the connections among quasars, galaxies, and dark matter haloes for redshifts 1 < z < 6. A key component of these models is that we enforce a self-consistent black hole (BH) history by tracking both BH mass and BH growth rate at all redshifts. We connect objects across redshift with a simple constant-number-density procedure, and choose a fiducial model with a relationship between BH and galaxy growth rates that is linear and evolves in a simple way with redshift. Within this fiducial model, we find the quasar luminosity function (QLF) by calculating an `intrinsic' luminosity based on either the BH mass or BH growth rate, and then choosing a model of quasar variability with either a lognormal or truncated power-law distribution of instantaneous luminosities. This gives four model variations, which we fit to the observed QLF at each redshift. With the best-fitting models in hand, we undertake a detailed comparison of the four fiducial models, and explore changes to our fiducial model of the BH-galaxy relationship. Each model variation can successfully fit the observed QLF, the shape of which is generally set by the `intrinsic' luminosity at the faint end and by the scatter due to variability at the bright end. We focus on accounting for the reasons why physically different models can make such similar predictions, and on identifying what observational data or physical arguments are most essential in breaking the degeneracies among models.

Veale, Melanie; White, Martin; Conroy, Charlie

2014-12-01

197

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

Microsoft Academic Search

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

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

2004-01-01

198

Butt Joint Tool Commissioning  

SciTech Connect

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

Martovetsky, N N

2007-12-06

199

Demographic and trophic dynamics of fishes in relation to hydrologic variation in channel and floodplain habitats of the Brazos River, Texas.  

E-print Network

demographic and trophic dynamics of fishes with divergent life histories and trophic guilds in relation to habitat heterogeneity and flow variability in a relatively unaltered floodplain system: the Brazos River, Texas. Reproductive activity of fishes...

Zeug, Steven Christopher

2009-06-02

200

The Demographic Transition Influences Variance in Fitness and Selection on Height and BMI in Rural Gambia  

PubMed Central

Summary Recent human history is marked by demographic transitions characterized by declines in mortality and fertility [1]. By influencing the variance in those fitness components, demographic transitions can affect selection on other traits [2]. Parallel to changes in selection triggered by demography per se, relationships between fitness and anthropometric traits are also expected to change due to modification of the environment. Here we explore for the first time these two main evolutionary consequences of demographic transitions using a unique data set containing survival, fertility, and anthropometric data for thousands of women in rural Gambia from 1956–2010 [3]. We show how the demographic transition influenced directional selection on height and body mass index (BMI). We observed a change in selection for both traits mediated by variation in fertility: selection initially favored short females with high BMI values but shifted across the demographic transition to favor tall females with low BMI values. We demonstrate that these differences resulted both from changes in fitness variance that shape the strength of selection and from shifts in selective pressures triggered by environmental changes. These results suggest that demographic and environmental trends encountered by current human populations worldwide are likely to modify, but not stop, natural selection in humans. PMID:23623548

Courtiol, Alexandre; Rickard, Ian J.; Lummaa, Virpi; Prentice, Andrew M.; Fulford, Anthony J.C.; Stearns, Stephen C.

2013-01-01

201

Family History  

MedlinePLUS

... Home CDC 24/7: Saving Lives. Protecting People.™ Genomics All CDC Topics Search The CDC Note: Javascript ... visit this page: About CDC.gov . Public Health Genomics Genomics Family Health History Share Compartir Family History ...

202

Family History  

MedlinePLUS

... Complications Post Treatment and Outcome GTranslate Understanding : Family History Familial intracranial aneurysms are generally defined as the ... patients with an Intracranial Aneurysm (IA) have a history of smoking at some time in their life. ...

203

Low cycle fatigue strength assessment of cruciform welded joints  

Microsoft Academic Search

This paper presents the results of an experimental study on the low cycle fatigue strength of cruciform welded joints. Tests were performed on 22 specimens of three different categories, namely full-penetration, partial-penetration and fillet welded cruciform joints. These tests consisted basically of imposing on each specimen a constant amplitude cyclic displacement history in the plastic range of the material behaviour.

João Ferreira; Carlo A Castiglioni; Luis Calado; M Rosaria Agatino

1998-01-01

204

Effects of contraction history on control and stability in explosive actions  

Microsoft Academic Search

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

G. J. C. Ettema

2002-01-01

205

Identifying image preferences based on demographic attributes  

NASA Astrophysics Data System (ADS)

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

Fedorovskaya, Elena A.; Lawrence, Daniel R.

2014-02-01

206

Surgical history.  

PubMed

The importance of surgical history for surgeons and students of this field of knowledge is undeniable. Knowing surgical history makes us aware of findings and discoveries we never knew before. Surgical history helps us in defining how surgery evolved through the centuries and mostly how those observations have shaped surgical thought. In this writing, I introduce my own observations of the field and explain how I grew to learn and appreciate the evolution of surgical history through my own personal experience. And, as important, at least for me, I narrate my observations as to how my education and contributions to the discipline shaped my knowledge of surgical history. PMID:20001807

Toledo-Pereyra, Luis H

2009-01-01

207

Large displacement spherical joint  

DOEpatents

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

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

2002-01-01

208

Joint Injection/Aspiration  

MedlinePLUS

... osteoarthritis. What usually is injected into the joint space? Corticosteroids (such as methylprednisolone and triamcinolone formulated to ... for producing inflammation and pain within the joint space. Although corticosteroids may also be successfully used in ...

209

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

SciTech Connect

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

Liebowitz, R.P.

1992-03-16

210

International Demographic Data Director. A Computerized Information Retrieval System for Demographic and Family Planning Data.  

ERIC Educational Resources Information Center

Announced in this booklet is the availability of the International Demographic Data Directory (IDDD). The IDDD is designed to expedite the retrieval of demographic and family planning statistics for use by administrators, planners, and researchers. This guide describes the computerized system indicating the geographic scope of the data, subject…

Bargar, Martha

211

Population momentum across vertebrate life histories  

USGS Publications Warehouse

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.

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

2006-01-01

212

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

213

Jointly Poisson processes  

Microsoft Academic Search

What constitutes jointly Poisson processes remains an unresolved issue. This report reviews the current state of the theory and indicates how the accepted but unproven model equals that resulting from the small time-interval limit of jointly Bernoulli processes. One intriguing consequence of these models is that jointly Poisson processes can only be positively correlated as measured by the correlation coefficient

D. H. Johnson; I. N. Goodman

2009-01-01

214

Demographic change and carbon dioxide emissions.  

PubMed

Relations between demographic change and emissions of the major greenhouse gas carbon dioxide (CO(2)) have been studied from different perspectives, but most projections of future emissions only partly take demographic influences into account. We review two types of evidence for how CO(2) emissions from the use of fossil fuels are affected by demographic factors such as population growth or decline, ageing, urbanisation, and changes in household size. First, empirical analyses of historical trends tend to show that CO(2) emissions from energy use respond almost proportionately to changes in population size and that ageing and urbanisation have less than proportional but statistically significant effects. Second, scenario analyses show that alternative population growth paths could have substantial effects on global emissions of CO(2) several decades from now, and that ageing and urbanisation can have important effects in particular world regions. These results imply that policies that slow population growth would probably also have climate-related benefits. PMID:22784534

O'Neill, Brian C; Liddle, Brant; Jiang, Leiwen; Smith, Kirk R; Pachauri, Shonali; Dalton, Michael; Fuchs, Regina

2012-07-14

215

Demographic analysis from summaries of an age-structured population  

USGS Publications Warehouse

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

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

2003-01-01

216

Ehlers-Danlos Syndrome: Relationship between Joint Hypermobility, Urinary Incontinence, and Pelvic Floor Prolapse  

Microsoft Academic Search

Objective: To compare the incidence of joint hypermobility and prolapse in incontinent and continent women with Ehlers-Danlos syndrome (EDS). Methods: Forty-six patients with EDS were evaluated by history and physical examination. The degree of joint mobility of shoulder, elbow, wrist, hip, knee, and ankle was evaluated by orthopedic surgeons and physical therapists. Joint range of motion measurements were obtained using

Lisa J. McIntosh; Deborah F. Stanitski; Veronica T. Mallett; Jane D. Frahm; David A. Richardson; Mark I. Evans

1996-01-01

217

Demographics of Black Vultures in North Carolina  

Microsoft Academic Search

Understanding the contributions of vital rates to species population growth is critical to developing new management protocols. We constructed a model population for black vultures (Coragyps atratus) in North Carolina, USA, based on demographic data from a 14-year study. The model population was similar in stage structure to the reference population, and adult survival was the primary contributor to the

Bradley F. Blackwell; Michael L. Avery; Bryan D. Watts; Martin S. Lowney

2007-01-01

218

Changing demographics and shrinking engineering enrollments  

SciTech Connect

This paper reports that changing U.S. population demographics, poor academic preparation, and a decreasing interest in engineering among college student indicate possible shortages ahead, particularly among chemical and petroleum engineers. If we are to ensure an adequate future supply for the U.S., the engineering talent pool must be enlarged to include women and minority men.

Vetter, B.M. (Commission on Professionals in Science and Technology (US))

1992-03-01

219

Demographics of international contact lens prescribing  

Microsoft Academic Search

Knowledge of differences in the demographics of contact lens prescribing between nations, and changes over time, can assist (a) the contact lens industry in developing and promoting various product types in different world regions, and (b) practitioners in understanding their prescribing habits in an international context. Data that we have gathered from annual contact lens fitting surveys conducted in Australia,

Philip B. Morgan; Nathan Efron; Magne Helland; Motozumi Itoi; Deborah Jones; Jason J. Nichols; Eef van der Worp; Craig A. Woods

2010-01-01

220

Religious Involvement, Audience Demographics, and Media Bias  

Microsoft Academic Search

This study sought to investigate the influence of religious involvement (religious partisanship, religiosity, and religious service attendance) as well as demographic factors (sex, ethnicity, and age) on the perception of media coverage of a controversial religious issue. Contrary to expectation none of the religious involvement measures were significant. However a significant effect for ethnicity on participants' perceptions of media bias

Jack Glascock; Curtis B. Livesay; Thomas E. Ruggiero

2008-01-01

221

Understanding China's Demographic Dividends and Labor Issue  

ERIC Educational Resources Information Center

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

Peng, Xizhe

2013-01-01

222

Chiropractors in Finland – a demographic survey  

Microsoft Academic Search

BACKGROUND: The Finnish chiropractic profession is young and not fully accepted by Finnish healthcare authorities. The demographic profile and style of practice has not been described to date. However, as the profession seems to be under rapid development, it would be of interest to stakeholders, both chiropractic and political, to obtain a baseline description of this profession with a view

Stefan Malmqvist; Charlotte Leboeuf-Yde

2008-01-01

223

A Demographic Profile of Cuban Americans.  

ERIC Educational Resources Information Center

This study offers a demographic profile of the U.S. Cuban population, using data from the decennial census and current population surveys. Part one estimates the number of Cuban Americans and describes their geographic distribution nationwide. Part two compares the socioeconomic characteristics (age, gender, educational attainment, income,…

Boswell, Thomas D.

224

Demographic Transition in China and its Implications  

Microsoft Academic Search

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

Athar Hussain

2002-01-01

225

Demographic Transitions in a Sicilian Rural Town  

Microsoft Academic Search

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

Jane Schneider; Peter Schneider

1984-01-01

226

Demographic Transition, Income Distribution, and Economic Growth  

Microsoft Academic Search

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

Momi Dahan; Daniel Tsiddon

1998-01-01

227

Population concentration, urbanization, and demographic transition  

Microsoft Academic Search

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

Yasuhiro Sato; Kazuhiro Yamamoto

2005-01-01

228

Population momentum for gradual demographic transitions  

Microsoft Academic Search

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

NAN LI; SHRIPAD TULJAPURKAR

1999-01-01

229

Evolutionary Demography Evolutionary Shaping of Demographic Schedules  

E-print Network

of Aging Thanks to Richard Suzman and NIA Grants 2P01-AG022500-06A1 and P30-AG012839. Kenneth W. Wachter success. It makes sense to try to understand the age-specific patterns realized in demographic schedules Points for Today: 11 January 2014 1 An overview of three strands of evolutionary demography: Mutation

Wachter, Kenneth W.

230

Changing demographics of peptic ulcer disease  

Microsoft Academic Search

The demography of peptic ulcer changed greatly and uniformly in western countries until the middle of this century. The demographic pattern reversed at about the turn of the century, duodenal ulcer becoming the predominant lesion, males the most often affected, and age-distribution shifting towards senior citizens. These changes have not continued beyond the 1950s, in fact a decline in the

O. Bonnevie

1985-01-01

231

A Model for External Demographic Analysis.  

ERIC Educational Resources Information Center

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

Hall, Barbara Ann

232

Human population growth and the demographic transition  

PubMed Central

The world and most regions and countries are experiencing unprecedentedly rapid demographic change. The most obvious example of this change is the huge expansion of human numbers: four billion have been added since 1950. Projections for the next half century expect a highly divergent world, with stagnation or potential decline in parts of the developed world and continued rapid growth in the least developed regions. Other demographic processes are also undergoing extraordinary change: women's fertility has dropped rapidly and life expectancy has risen to new highs. Past trends in fertility and mortality have led to very young populations in high fertility countries in the developing world and to increasingly older populations in the developed world. Contemporary societies are now at very different stages of their demographic transitions. This paper summarizes key trends in population size, fertility and mortality, and age structures during these transitions. The focus is on the century from 1950 to 2050, which covers the period of most rapid global demographic transformation. PMID:19770150

Bongaarts, John

2009-01-01

233

Demographic Group Differences in Adolescents' Time Attitudes  

ERIC Educational Resources Information Center

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

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

2013-01-01

234

Demographic characteristics of elite Kenyan endurance runners  

Microsoft Academic Search

Kenyan athletes have dominated international distance running in recent years. Explanations for their success include favourable physiological characteristics, which could include favourable genetic endowment, and advantageous environmental conditions. The aim of this study was to compare the demographic characteristics of elite Kenyan runners with those of the general Kenyan population. Questionnaires, administered to 404 elite Kenyan runners specializing in distances

Vincent O. Onywera; Robert A. Scott; Michael K. Boit; Yannis P. Pitsiladis

2006-01-01

235

Ghana. Country Demographic Profiles, No. 5.  

ERIC Educational Resources Information Center

Tables of demographic information about Ghana are presented, including size of population and estimates of fertility and mortality. The data were obtained primarily from population censuses in 1960 and 1970, a 1960 post-enumeration survey, and a 1971 supplementary enquiry. Because Ghana's vital registration system is incomplete, the data are not…

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

236

Demographic Discontinuity: Another Explanation for Consumerism?  

ERIC Educational Resources Information Center

This explanation for consumerism focuses on how unique demographics may have contributed to the movement. Prior movements may not have achieved the scale of the most recent movement because they did not occur after a period of rapid population growth. (Author/JOW)

Carlson, Les; Kangun, Norman

1988-01-01

237

Forcing anomalous scaling on demographic fluctuations.  

PubMed

We discuss the conditions under which a population of anomalously diffusing individuals can be characterized by demographic fluctuations that are anomalously scaling themselves. Two examples are provided in the case of individuals migrating by Gaussian diffusion, and by a sequence of Lévy flights. PMID:23214831

Olla, Piero

2012-11-01

238

Demographic and Lifestyle Variables Associated with Obesity  

ERIC Educational Resources Information Center

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

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

2010-01-01

239

Temporomandibular joint dislocation: experiences from Zaria, Nigeria  

PubMed Central

Objectives Dislocation of the temporomandibular joint may occur for various reasons. Although different invasive methods have been advocated for its treatment, this study highlights the value of non-invasive treatment options even in chronic cases in a resource-poor environment. Materials and Methods A seven-year retrospective analysis of all patients managed for temporomandibular joint dislocation in our department was undertaken. Patient demographics, risk factors associated with temporomandibular joint dislocation and treatment modalities were retrieved from patient records. Results In all, 26 patients were managed over a seven-year period. Males accounted for 62% of the patients, and yawning was the most frequent etiological factor. Conservative treatment methods were used successfully in 86.4% of the patients managed. Two (66.7%) of the three patients who needed surgical treatment developed complications, while only one (5.3%) patient who was managed conservatively developed complications. Conclusion Temporomandibular joint dislocation appears to be associated with male sex, middle age, yawning, and low socio-economic status, although these observed relationships were not statistically significant. Non-invasive methods remain an effective treatment option in this environment in view of the low socio-economic status of the patients affected. PMID:25045637

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

2014-01-01

240

History Explorer  

NSDL National Science Digital Library

There are many ways to explore the various facets of history, and some of the world's leading museums have come up with a host of online multimedia tools to bring people into this subject that is sometimes erroneously perceived to be dry and uninteresting. The inventive people at the National Museum of American History have recently developed the History Explorer which allows those surfing the Web to browse through an interactive timeline of American history. The interface is composed of items from the Museum's various online collections, exhibitions and programs, such as Plymouth Rock and a world map from 1511. Visitors can zoom in and out through the timeline and its objects and also elect to toggle on or off various themes, such as "Arts and Culture", "Peopling America", and "Politics and Reform". Overall, this is a very well-thought-out tool for learning about American history and one that will engage a wide range of persons.

241

Digital History  

NSDL National Science Digital Library

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

242

Malnutrition and socio-demographic factors associated with pulmonary tuberculosis in Timor and Rote Islands, Indonesia  

Microsoft Academic Search

OBJECTIVE: To identify nutritional and socio-demographic factors for the development of tuberculosis (TB) in Timor and Rote Island, Indonesia, so that intervention programmes can be developed to address these factors. METHODS: In a case-control study, we enrolled new sputum smear-positive pulmonary TB patients as cases, and neighbours matched for sex and age as controls. Data obtained included history of TB,

T. A. Pakasi; E. Karyadi; W. M. V. Dolmans; J. van der Velden

2009-01-01

243

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

Microsoft Academic Search

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

Tomáš Sobotka; Kryštof Zeman; Vladimíra Kantorová

2003-01-01

244

Some demographic issues affecting private health insurance.  

PubMed

There will be significant changes in the demography of persons with Private Health Insurance (PHI). Two methods of projecting PHI coverage are discussed in this paper. The first assumes the only factors affecting PHI coverage are demographic change and mortality and facilitates comparisons between actual and projected PHI coverage. The second projects the percentage of the population insured in each five year age cohort, and makes allowance for changes in PHI coverage due to all factors. Demographic change will increase Registered Health Benefit Organization (RHBO) premiums by 1.7% per annum. The role of these projections in analysing the effect of future premium increases on PHI retention rates is also discussed. PMID:15362293

Hanning, Brian

2004-01-01

245

Complexity and Demographic Explanations of Cumulative Culture  

PubMed Central

Formal models have linked prehistoric and historical instances of technological change (e.g., the Upper Paleolithic transition, cultural loss in Holocene Tasmania, scientific progress since the late nineteenth century) to demographic change. According to these models, cumulation of technological complexity is inhibited by decreasing— while favoured by increasing—population levels. Here we show that these findings are contingent on how complexity is defined: demography plays a much more limited role in sustaining cumulative culture in case formal models deploy Herbert Simon's definition of complexity rather than the particular definitions of complexity hitherto assumed. Given that currently available empirical evidence doesn't afford discriminating proper from improper definitions of complexity, our robustness analyses put into question the force of recent demographic explanations of particular episodes of cultural change. PMID:25048625

Querbes, Adrien; Vaesen, Krist; Houkes, Wybo

2014-01-01

246

Is the demographic dividend an education dividend?  

PubMed

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

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

2014-02-01

247

The AAVSO 2011 Demographic and Background Survey  

E-print Network

In 2011, the AAVSO conducted a survey of 615 people who are or were recently active in the 101-year old organization. The survey included questions about their demographic background and variable star interests. Data are descriptively analyzed and compared with prior surveys. Results show an organization of very highly educated, largely male amateur and professional astronomers distributed across 108 countries. Participants tend to be loyal, with the average time of involvement in the AAVSO reported as 14 years. Most major demographic factors have not changed much over time. However, the average age of new members is increasing. Also, a significant portion of the respondents report being strictly active in a non-observing capacity, reflecting the growing mission of the organization. Motivations of participants are more aligned with scientific contribution than with that reported by other citizen science projects. This may help explain why a third of all respondents are an author or co-author of a paper in an ...

Price, C Aaron

2012-01-01

248

Simulation of Demographic Change in Palestinian Territories  

NASA Astrophysics Data System (ADS)

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

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

249

Demographic and health surveillance: longitudinal ethical considerations.  

PubMed

Longitudinal data gathered from health surveillance, when combined with detailed demographic information, can provide invaluable insight into disease outcomes. Many such surveillance sites exist in the developing world, particularly in Asia and sub-Saharan Africa, and focus on diseases such as HIV/AIDS, cholera, malaria and tuberculosis. The indistinct positions of such surveillance systems, often inhabiting an area between research, treatment and population health monitoring, means that the necessity of and responsibility for ethical oversight is unclear. This regulatory vacuum is further compounded by a lack of attention to longitudinal surveillance systems in ethics literature. In this paper, we explore some key ethical questions that arise during demographic and health surveillance in relation to ethical principles of beneficence, respect for persons and justice: health-care provision, informed consent and study sustainability. PMID:18797619

Carrel, Margaret; Rennie, Stuart

2008-08-01

250

The Demographic Transition: Causes and Consequences  

PubMed Central

This paper develops the theoretical foundations and the testable implications of the various mechanisms that have been proposed as possible triggers for the demographic transition. Moreover, it examines the empirical validity of each of the theories and their significance for the understanding of the transition from stagnation to growth. The analysis suggests that the rise in the demand for human capital in the process of development was the main trigger for the decline in fertility and the transition to modern growth PMID:25089157

Galor, Oded

2013-01-01

251

Soft Selective Sweeps in Complex Demographic Scenarios  

PubMed Central

Adaptation from de novo mutation can produce so-called soft selective sweeps, where adaptive alleles of independent mutational origin sweep through the population at the same time. Population genetic theory predicts that such soft sweeps should be likely if the product of the population size and the mutation rate toward the adaptive allele is sufficiently large, such that multiple adaptive mutations can establish before one has reached fixation; however, it remains unclear how demographic processes affect the probability of observing soft sweeps. Here we extend the theory of soft selective sweeps to realistic demographic scenarios that allow for changes in population size over time. We first show that population bottlenecks can lead to the removal of all but one adaptive lineage from an initially soft selective sweep. The parameter regime under which such “hardening” of soft selective sweeps is likely is determined by a simple heuristic condition. We further develop a generalized analytical framework, based on an extension of the coalescent process, for calculating the probability of soft sweeps under arbitrary demographic scenarios. Two important limits emerge within this analytical framework: In the limit where population-size fluctuations are fast compared to the duration of the sweep, the likelihood of soft sweeps is determined by the harmonic mean of the variance effective population size estimated over the duration of the sweep; in the opposing slow fluctuation limit, the likelihood of soft sweeps is determined by the instantaneous variance effective population size at the onset of the sweep. We show that as a consequence of this finding the probability of observing soft sweeps becomes a function of the strength of selection. Specifically, in species with sharply fluctuating population size, strong selection is more likely to produce soft sweeps than weak selection. Our results highlight the importance of accurate demographic estimates over short evolutionary timescales for understanding the population genetics of adaptation from de novo mutation. PMID:24929828

Wilson, Benjamin A.; Petrov, Dmitri A.; Messer, Philipp W.

2014-01-01

252

Demographic implications of the Russian mortality crisis  

Microsoft Academic Search

The Russian mortality crisis of 1990–1995 represents the most precipitous decline in national life expectancy ever recorded in the absence of war, oppression, famine, or major disease. Using standard demographic techniques, we develop a model Russian mortality schedule. Applying this schedule, we estimate that there were 1.36 to 1.57 million premature deaths during 1990–1995, equivalent to between 14 and 16%

Serguey F. Ivanov; David E. Bloom

1998-01-01

253

to combining animal abundance and demographic data  

Microsoft Academic Search

A Bayesian approach to combining animal abundance and demographic data.— In studies of wild animals, one frequently encounters both count and mark-recapture-recovery data. Here, we consider an integrated Bayesian analysis of ring-recovery and count data using a state-space model. We then impose a Leslie- matrix-based model on the true population counts describing the natural birth-death and age transition processes. We

A Bayesian; S. P. Brooks; R. King; B. J. T. Morgan

254

Soft selective sweeps in complex demographic scenarios.  

PubMed

Adaptation from de novo mutation can produce so-called soft selective sweeps, where adaptive alleles of independent mutational origin sweep through the population at the same time. Population genetic theory predicts that such soft sweeps should be likely if the product of the population size and the mutation rate toward the adaptive allele is sufficiently large, such that multiple adaptive mutations can establish before one has reached fixation; however, it remains unclear how demographic processes affect the probability of observing soft sweeps. Here we extend the theory of soft selective sweeps to realistic demographic scenarios that allow for changes in population size over time. We first show that population bottlenecks can lead to the removal of all but one adaptive lineage from an initially soft selective sweep. The parameter regime under which such "hardening" of soft selective sweeps is likely is determined by a simple heuristic condition. We further develop a generalized analytical framework, based on an extension of the coalescent process, for calculating the probability of soft sweeps under arbitrary demographic scenarios. Two important limits emerge within this analytical framework: In the limit where population-size fluctuations are fast compared to the duration of the sweep, the likelihood of soft sweeps is determined by the harmonic mean of the variance effective population size estimated over the duration of the sweep; in the opposing slow fluctuation limit, the likelihood of soft sweeps is determined by the instantaneous variance effective population size at the onset of the sweep. We show that as a consequence of this finding the probability of observing soft sweeps becomes a function of the strength of selection. Specifically, in species with sharply fluctuating population size, strong selection is more likely to produce soft sweeps than weak selection. Our results highlight the importance of accurate demographic estimates over short evolutionary timescales for understanding the population genetics of adaptation from de novo mutation. PMID:25060100

Wilson, Benjamin A; Petrov, Dmitri A; Messer, Philipp W

2014-10-01

255

Rural Household Demographics, Livelihoods and the Environment  

PubMed Central

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

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

2008-01-01

256

Climate History  

NSDL National Science Digital Library

This climate history website of the PALEOMAP project provides information on climates during past geological eras using maps and animations. Also included is a discussion of the methods used to evaluate historical climate conditions.

Scotese, Christopher R.

257

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

ERIC Educational Resources Information Center

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…

Slayter, Elspeth Maclean

2010-01-01

258

Historical sampling reveals dramatic demographic changes in western gorilla populations  

PubMed Central

Background Today many large mammals live in small, fragmented populations, but it is often unclear whether this subdivision is the result of long-term or recent events. Demographic modeling using genetic data can estimate changes in long-term population sizes while temporal sampling provides a way to compare genetic variation present today with that sampled in the past. In order to better understand the dynamics associated with the divergences of great ape populations, these analytical approaches were applied to western gorillas (Gorilla gorilla) and in particular to the isolated and Critically Endangered Cross River gorilla subspecies (G. g. diehli). Results We used microsatellite genotypes from museum specimens and contemporary samples of Cross River gorillas to infer both the long-term and recent population history. We find that Cross River gorillas diverged from the ancestral western gorilla population ~17,800 years ago (95% HDI: 760, 63,245 years). However, gene flow ceased only ~420 years ago (95% HDI: 200, 16,256 years), followed by a bottleneck beginning ~320 years ago (95% HDI: 200, 2,825 years) that caused a 60-fold decrease in the effective population size of Cross River gorillas. Direct comparison of heterozygosity estimates from museum and contemporary samples suggests a loss of genetic variation over the last 100 years. Conclusions The composite history of western gorillas could plausibly be explained by climatic oscillations inducing environmental changes in western equatorial Africa that would have allowed gorilla populations to expand over time but ultimately isolate the Cross River gorillas, which thereafter exhibited a dramatic population size reduction. The recent decrease in the Cross River population is accordingly most likely attributable to increasing anthropogenic pressure over the last several hundred years. Isolation of diverging populations with prolonged concomitant gene flow, but not secondary admixture, appears to be a typical characteristic of the population histories of African great apes, including gorillas, chimpanzees and bonobos. PMID:21457536

2011-01-01

259

Estimating Demographic Parameters with Uncertainty from Fragmentary Data  

E-print Network

Estimating Demographic Parameters with Uncertainty from Fragmentary Data Mark C. Wheldon, Adrian E Transitions Research Unit (Agincourt), School of Public Health, Faculty of Health Sciences, University collected in modern demographic surveys and censuses. Population dynamics over the period of reconstruction

Washington at Seattle, University of

260

Impact of demographics on supply chain risk management practices  

E-print Network

Do demographic factors play a role in the choice of supply chain risk management practices by supply chain professionals? Are there stronger relationships between certain demographic factors and supply chain risk management ...

Kanyagui, Kenneth (Kenneth K.)

2010-01-01

261

Joint hypermobility in adults referred to rheumatology clinics.  

PubMed Central

Joint hypermobility is a rarely recognised aetiology for focal or diffuse musculoskeletal symptoms. To assess the occurrence and importance of joint hypermobility in adult patients referred to a rheumatologist, we prospectively evaluated 130 consecutive new patients for joint hypermobility. Twenty women (15%) had joint hypermobility at three or more locations (greater than or equal to 5 points on a 9 point scale). Most patients with joint hypermobility had common musculoskeletal problems as the reason for referral. Two patients referred with a diagnosis of rheumatoid arthritis were correctly reassigned a diagnosis of hypermobility syndrome. Three patients with systemic lupus erythematosus had diffuse joint hypermobility. There was a statistically significant association between diffuse joint hypermobility and osteoarthritis. Most patients (65%) had first degree family members with a history of joint hypermobility. These results show that joint hypermobility is common, familial, found in association with common rheumatic disorders, and statistically associated with osteoarthritis. The findings support the hypothesis that joint hypermobility predisposes to musculoskeletal disorders, especially osteoarthritis. PMID:1616366

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

1992-01-01

262

Demographic Approaches to Assessing Climate Change Impact  

E-print Network

between many species' life histories and aquatic hydropattern, which is the "normal" cycling of high-Breeding Frogs and Shifting Hydropatterns John H. Matthews, W. Chris Funk, and Cameron K. Ghalambor Applications ecosystems through their life histories, amphibians may be especially vulnerable to climate change impacts

Funk, W. Chris

263

Joint warfare system (JWARS)  

Microsoft Academic Search

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

A. Simlote

2003-01-01

264

Campylobacter Prosthetic Joint Infection  

PubMed Central

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

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

2014-01-01

265

Industrial energy use and the human life history  

PubMed Central

The demographic rates of most organisms are supported by the consumption of food energy, which is used to produce new biomass and fuel physiological processes. Unlike other species, modern humans use ‘extra-metabolic' energy sources acquired independent of physiology, which also influence demographics. We ask whether the amount of extra-metabolic energy added to the energy budget affects demographic and life history traits in a predictable way. Currently it is not known how human demographics respond to energy use, and we characterize this response using an allometric approach. All of the human life history traits we examine are significant functions of per capita energy use across industrialized populations. We find a continuum of traits from those that respond strongly to the amount of extra-metabolic energy used, to those that respond with shallow slopes. We also show that the differences in plasticity across traits can drive the net reproductive rate to below-replacement levels. PMID:22355575

Burger, Oskar; DeLong, John P.; Hamilton, Marcus J.

2011-01-01

266

Understanding and Using Demographic Data: Terms and Measures.  

ERIC Educational Resources Information Center

This publication provides program planners and others with information and analytical tools for using demographic data in program planning, implementation, and evaluation. The report reviews the importance of demographic data and their relevance to programs and proper implementation of laws, discusses the collection of demographic information by…

Lilley, Stephen

267

Demographic Transition and Economic Welfare: The Role of Humanitarian Aid  

E-print Network

1 Demographic Transition and Economic Welfare: The Role of Humanitarian Aid Stephen M. Miller to demographic transition are also explored. The evaluation of the effectiveness of aid on economic growth.neanidis@manchester.ac.uk Abstract This paper considers the effects of humanitarian aid on economic welfare through a demographic

Ahmad, Sajjad

268

NBER WORKING PAPER SERIES AFRICA'S LAGGING DEMOGRAPHIC TRANSITION  

E-print Network

NBER WORKING PAPER SERIES AFRICA'S LAGGING DEMOGRAPHIC TRANSITION: EVIDENCE FROM EXOGENOUS IMPACTS;Africa's Lagging Demographic Transition: Evidence from Exogenous Impacts of Malaria Ecology February 2007 JEL No. I1,J11 ABSTRACT Much of Africa has not yet gone through a "demographic transition

269

Marriage Market Implications of the Demographic Department of Economics  

E-print Network

Marriage Market Implications of the Demographic Transition V Bhaskar Department of Economics in cohort size in the second phase of the demographic transition worsens the position of women. This e for research assistance. 0 #12;1 Introduction The demographic transition has major implications

Royal Holloway, University of London

270

Population studies, No. 43 Demographic and social implications  

E-print Network

and the demographic consequences of economic transition. These publications provide essential background informationPopulation studies, No. 43 Demographic and social implications of low fertility for family to the understanding of the relationship between social policy and demographic issues in Europe. The findings

Løw, Erik

271

Introduction: History’s Pathways  

Microsoft Academic Search

\\u000a “History” is a deceptively simple concept. It invokes the notions of change over time, human agency, the role of material\\u000a circumstances in human affairs, and the question of the putative meaning of historical events. It raises the possibility of\\u000a “learning from history”—whether from the experience of the Peloponnesian War or the Korean War, the 1918 avian influenza pandemic\\u000a or the

Daniel Little

272

Hip joint replacement - series (image)  

MedlinePLUS

... pain that limits what you can do. Hip joint replacement is usually done in people age 60 and ... Hip joint replacement is surgery to replace all or part of the hip joint with a man-made or artificial ...

273

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.

274

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

PubMed

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. PMID:25223336

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

2014-01-01

275

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)

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.

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

2014-09-01

276

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

PubMed Central

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. PMID:25223336

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

2014-01-01

277

Pressure vessel flex joint  

NASA Technical Reports Server (NTRS)

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

Kahn, Jon B. (inventor)

1992-01-01

278

Handbook on dynamics of jointed structures.  

SciTech Connect

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

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

2009-07-01

279

Intra metropolitan demographic structure: a Seattle example.  

PubMed

"Internal urban variation in demographic character (births, deaths, fertility, natural increase, net migration) is analyzed in relation to age of persons, age of housing, ownership, distance from the CBD [central business district], race, household type and size. A descriptive analysis of maps of these characteristics is followed by simple statistical tests of relations among the variables, in particular distance from the city center. Predictable and strong patterns of spatial structure are consonant with expectations from economic, social, geographic and political urban theory." Data concern King County, Washington, for the period 1980-1985, (the city of Seattle) and are from local sources, including the Puget Sound Council of Governments. PMID:12341632

Morrill, R L

1988-03-01

280

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

E-print Network

revealed a history of sex-biased migration patterns that can vary widely across human populationsUnraveling 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

Wilkins, Jon F.

281

The Evolution of Transfers and Life Histories  

PubMed Central

Much of life history theory analyzes life histories of independent, isolated individuals, who grow, forage, reproduce, and die. However, in many species social interactions such as food sharing are a key part of the life history strategy, altering the energetic budget constraint. Transfers and sharing raise reproductive success and also alter the fitness impact of other aspects of the life history. We discuss a variety of traits and behaviors for which transfers are important, synthesizing results from a number of earlier papers. Topics include the U-shaped mortality curve, post reproductive survival, causes of early life mortality decline, why intergenerational transfers evolve and co-evolve with longevity, time preference, sexual dimorphism and sexual differences in transfers, menopause, demographic advantages of social sharing, and consequences of social sharing for life history evolution. PMID:22750486

Cyrus, C. Y.

2012-01-01

282

Acromioclavicular joint dislocations.  

PubMed

Acromioclavicular (AC) dislocation is a common injury especially among sportsmen. There is still a lack of consensus on whether to conserve or operate type III AC joint dislocations. Even among surgeons inclined to operate AC joint dislocations there is no unanimity on which surgical technique. There are a plethora of choices between mechanical fixation or synthetic materials or biologic anatomic reconstructions. Even among surgeons, there is a choice between open repairs and the latest-arthroscopic reconstructions. This review of AC joint dislocations intends to analyze the available surgical options, a critical analysis of existing literature, actual technique of anatomic repair, and also accompanying complications. PMID:24431027

Babhulkar, Ashish; Pawaskar, Aditya

2014-03-01

283

Anterior glenohumeral joint dislocations.  

PubMed

The glenohumeral joint is the most mobile articulation in the body and the most commonly dislocated diarthroidal joint. Anterior dislocation is by far the most common direction and can lead to instability of the glenohumeral joint, which ranges from subtle increased laxity to recurrent dislocation. Overtime, understanding of anterior shoulder dislocations and the resulting instability has improved. Likewise, significant advances in arthroscopic equipment have allowed use of the arthroscope to address anatomically the various lesions that cause instability. This article reviews the anatomy, pathophysiology, clinical evaluation, and treatment of anterior shoulder instability. PMID:18803980

Dodson, Christopher C; Cordasco, Frank A

2008-10-01

284

History of San Marco  

NASA Technical Reports Server (NTRS)

A brief history is reported of the first San Marco project, a joint program of the United States and Italy. The Project was a three phase effort to investigate upper air density and associated ionosphere phenomena. The initial phase included the design and development of the spacecraft, the experiments, the launch complex, and a series of suborbital flights, from Wallops Island. The second phase, consisting of designing, fabricating, and testing a spacecraft for the first orbital mission, culminated in an orbital launch also from Wallops Island. The third phase consisted of further refining the experiments and spacecraft instrumentation and of establishing a full-bore scout complex in Kenya. The launch of San Marco B, in April 1967, from this complex into an equatorial orbit, concluded the initial San Marco effort.

Caporale, A. J.

1968-01-01

285

History & Policy  

NSDL National Science Digital Library

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

286

Making History  

ERIC Educational Resources Information Center

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

Shein, Esther

2008-01-01

287

CARIBBEAN BEEKEEPING CONGRESS: Guidelines for Country Reports Country reports are intended to summarise the history of the beekeeping sector, its current  

E-print Network

to summarise the history of the beekeeping sector, its current status, and recommendation/plans for the future developing its competitiveness. 1. HISTORY / BACKGROUND OF BEEKEEPING 2. BEEKEEPING DEMOGRAPHICS No

Jawitz, James W.

288

Prospective Demographic Study of Cosmetic Surgery Patients  

PubMed Central

Objectives: The authors sought to examine and assess cosmetic surgery patient demographics as well as age in relation to partner, in a prospective manner, analyzing data for any significant correlations. Design: The authors conducted a prospective study utilizing a survey. Setting: The study was conducted in a private, nonacademic dermatological practice. Participants: Three hundred thirty-six patients participated in this study. Results: Demographics of onabotulinumtoxinA/abobotulinumtoxinA (neurotoxins), fillers, and laser hair removal users were studied. The data show that the average private practice cosmetic surgery patient in this study is a married (67.5%), college-educated or greater (66.9%), employed (74.3%), mother (74.5%). In the fillers category, 50 percent of women were older than their partners, as opposed to 14.8 percent in 2008 Census data. Additionally, women were more educated and employed to a higher percentage than similar women in 2008 Census data. Data on motivations were statistically not significant. Conclusion: Data from this study show potential correlations with Census data norms in marital status and motherhood status categories, but not in the age in relation to partner, education, and employment level categories. Motivations of individuals undergoing cosmetic surgery will need further analysis in future studies. PMID:21103314

Schlessinger, Daniel; Schlessinger, Bernard

2010-01-01

289

Demographic Characteristics of World Class Jamaican Sprinters  

PubMed Central

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

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

2013-01-01

290

Climatic influence on demographic parameters of a tropical seabird varies with age and sex.  

PubMed

In marine ecosystems climatic fluctuation and other physical variables greatly influence population dynamics, but differential effects of physical variables on the demographic parameters of the two sexes and different age classes are largely unexplored. We analyzed the effects of climate on the survival and recruitment of both sexes and several age classes of a long-lived tropical seabird, the Blue-footed Booby (Sula nebouxii), using long-term observations on marked individuals. Results demonstrated a complex interaction between yearly fluctuations in climate (both local and global indexes, during both winter and breeding season) and the sex and age of individuals. Youngest birds' survival and recruitment were commonly affected by local climate, whereas oldest birds' parameters tended to be constant and less influenced by environmental variables. These results confirm the theoretical prediction that sex- and age-related variation in life-history demographic traits is greater under poor environmental conditions, and they highlight the importance of including variability in fitness components in demographic and evolutionary models. Males and females showed similar variation in survival but different recruitment patterns, in relation to both age and the spatial scale of climatic influence (local or global). Results indicate different life-history tactics for each sex and different ages, with birds likely trying to maximize their fitness by responding to the environmental contingencies of each year. PMID:20462134

Oro, Daniel; Torres, Roxana; Rodríguez, Cristina; Drummond, Hugh

2010-04-01

291

Improved orthopedic arm joint  

NASA Technical Reports Server (NTRS)

Joint permits smooth and easy movement of disabled arm and is smaller, lighter and less expensive than previous models. Device is interchangeable and may be used on either arm at the shoulder or at the elbow.

Dane, D. H.

1971-01-01

292

Joint Services Electronics Program.  

National Technical Information Service (NTIS)

An annual report of the JSEP (Joint Services Electronics Program) in solid state electronics, quantum electronics, information electronics, control and optimization, and electromagnetic phenomena is presented. Results of the research to date are summarize...

M. Tinkham

1991-01-01

293

Joint Services Electronics Program.  

National Technical Information Service (NTIS)

An annual report of the JSEP (Joint Services Electronics Program) in solid state electronics, quantum electronics, information electronics, control and optimization, and electromagnetic phenomena is presented. Results of the research to date are summarize...

M. Tinkham

1987-01-01

294

Joint Services Electronics Program.  

National Technical Information Service (NTIS)

An annual report of the JSEP (Joint Services Electronic Program) in solid state electronics, quantum electronics, information electronics control and optimization and electromagnetic phenomenon is presented. Results of the research to date are summarized ...

M. Tinkham

1985-01-01

295

JOINT SEMINAR FINAL REPORT  

E-print Network

evolving from the Joint Seminar. - Peer-reviewed publications (journals, contribution to anthologies, working papers, proceedings, etc.) - Non peer-reviewed publications (journals, contribution to anthologies Application guidelines Length Clarity Intelligibility Procedures (submission, review, decision) Advising

Fuchs, Clemens

296

Culture - joint fluid  

MedlinePLUS

Joint fluid culture ... fungi, or viruses grow. This is called a culture. If such microorganisms are detected, other tests may ... is no special preparation needed for the lab culture. For information on preparing for the removal of ...

297

Encyclopedia of Oklahoma History & Culture  

NSDL National Science Digital Library

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

298

Joint hypermobility syndrome pain  

Microsoft Academic Search

Joint hypermobility syndrome (JHS) was initially defined as the occurrence of musculoskeletal symptoms in the presence of\\u000a joint laxity and hypermobility in otherwise healthy individuals. It is now perceived as a commonly overlooked, underdiagnosed,\\u000a multifaceted, and multisystemic heritable disorder of connective tissue (HDCT), which shares many of the phenotypic features\\u000a of other HDCTs such as Marfan syndrome and Ehlers-Danlos syndrome.

Rodney Grahame

2009-01-01

299

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

300

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

PubMed Central

This paper describes methods used in the project “Orofacial Pain Prospective Evaluation and Risk Assessment” (OPPERA) and evaluates socio-demographic characteristics associated with temporomandibular disorders (TMD) in the OPPERA case-control study. Representativeness was investigated by comparing socio-demographic profiles of OPPERA participants with population census profiles of counties near study sites and by comparing age- and gender-associations with TMD in OPPERA and the 2007-09 US National Health Interview Survey. Volunteers aged 18-44 years were recruited at four US study sites: 3,263 people without TMD were enrolled into the prospective cohort study; 1,633 of them were selected as controls for the baseline case-control study. Cases were 185 volunteers with examiner-classified TMD. Distributions of some demographic characteristics among OPPERA participants differed from census profiles, although there was less difference in socio-economic profiles. Odds of TMD was associated with greater age in this 18-44 year range; females had three times the odds of TMD as males; and relative to non-Hispanic-Whites, other racial groups had one-fifth the odds of TMD. Age- and gender-associations with chronic TMD were strikingly similar to associations observed in the US population. Assessments of representativeness in this demographically diverse group of community volunteers suggest that OPPERA case-control findings have good internal validity. PMID:22074749

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

2011-01-01

301

High pressure ceramic joint  

DOEpatents

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

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

1993-01-01

302

Demographic evidence of illegal harvesting of an endangered asian turtle.  

PubMed

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

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

2013-12-01

303

Joint Workshop on Social Dynamics and Personal Attributes in Social Media  

E-print Network

such as: inferring user/customer demographic profiles (gender, age, religion, social status, race, ethnicity, origin); predicting user interests (sports, movies) and preferences (political favorites biases for personal analytics in social media � Joint latent attribute prediction (e.g., age together

304

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.

305

Organ History  

NSDL National Science Digital Library

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.

Cook, James H.

306

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.

307

Pennsylvania History  

NSDL National Science Digital Library

If you know someone who is fascinated with the history of Pennsylvania, they will want to explore this site in great detail. Created by the Pennsylvania Historical and Museum Commission, the site brings together primary documents, photographs, and a timeline of Keystone State history. The sections here include People, Places, Events, and Things. Users with a penchant for material culture will love the Things area, as it features topical sections covering Canals, Archaeology, Railroads, and Roads. The Places area provides meditations and narrative essays on the Governor's Residence and the long-gone French Asylum on the Susquehanna River, which was actually more of a utopian outpost of sorts. Also, the People area profiles well- and lesser-known individuals who left their mark on the state, including William Penn, Ida Tarbell, and noted military man, Henry Bouquet.

308

History uncovered  

E-print Network

) are still cited for models of the undergraduate research process: a process usually starting with anxiety and confusion and characterized by haphazard information-seeking strategies. Head (2008) found that undergraduates primarily use their course... attempts were made to collect data from different subject groups, there were no American historians and only one extra-European historian interviewed. The subject groups of the faculty members interviewed were: Ancient and Medieval History, Modern...

Keim, Carolyn

309

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

PubMed Central

Objective?To examine the relationships of demographic, maltreatment, neurostructural and neuropsychological measures with total posttraumatic stress disorder (PTSD) symptoms.?Methods?Participants included 216 children with maltreatment histories (N = 49), maltreatment and PTSD (N = 49), or no maltreatment (N = 118). Participants received diagnostic interviews, brain imaging, and neuropsychological evaluations.?Results?We examined a hierarchical regression model comprised of independent variables including demographics, trauma and maltreatment-related variables, and hippocampal volumes and neuropsychological measures to model PTSD symptoms. Important independent contributors to this model were SES, and General Maltreatment and Sexual Abuse Factors. Although hippocampal volumes were not significant, Visual Memory was a significant contributor to this model.?Conclusions?Similar to adult PTSD, pediatric PTSD symptoms are associated with lower Visual Memory performance. It is an important correlate of PTSD beyond established predictors of PTSD symptoms. These results support models of developmental traumatology and suggest that treatments which enhance visual memory may decrease symptoms of PTSD. PMID:20008084

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

2010-01-01

310

Stabilization of the sacroiliac joint.  

PubMed

Lower back pain and pain involving the area of the posterior iliac spine are extremely common. Degeneration of the sacroiliac joint (SIJ) is one potential cause for lower back pain and pain radiating into the groin or buttocks. Degenerative changes to the lumbar spine and sacroiliac joints are common. A recent study evaluating SIJ abnormalities in a primary low back pain population demonstrated 31.7% of patients demonstrated SI joint abnormalities. (4) As is the case for the evaluation and management of isolated lower back pain, the evaluation, management, and role for surgical intervention in SIJ pain is very controversial. Many patients have degenerative changes of the disc, facet joints, and SIJs. A recent systematic review performed to determine the diagnostic accuracy of tests available to clinicians to identify the disc, facet joint, or SIJ as the source of low back pain concluded that tests do exist that change the probability of the disc or SIJ (but not the facet joint) as the source of low back pain. (3) It was also concluded that the usefulness of these tests in clinical practice, particularly for guiding treatment selection, remains unclear. (3) Although there is general agreement that SIJ pathological changes are a potential cause of pain, there is far less agreement about the optimal management of these conditions. A variety of conditions can cause SIJ dysfunction including degenerative and inflammatory arthritis, trauma, prior lumbosacral fusion, hip arthritis, limb length inequality, infections, and neoplasia. (8) There is increasing evidence that image intensifier-guided single periarticular injection can correctly localize pain to the SIJ but the optimal management strategy remains controversial. Recent publications have compared surgical versus injection treatments and fusion versus denervation procedures. (1 , 8) A systematic review found improvement regardless of the treatment, with most studies reporting over 40% improvement in pain as measured by VAS or NRS scores. (8) It cautioned that one of the studies reported 17.6% of patients experiencing mild/no pain compared with 82.4% experiencing marked/severe pain at 39 months after SIJ fusion procedures. (6 , 8) This systematic review also noted that despite improvements in reported pain, less than half of patients who had work status reported as returning to work. (8) Because of the functional and socioeconomic consequences of chronic lower back pain, numerous surgical treatments to improve this condition have been attempted by spinal surgeons through the years. Arthrodesis of the SIJ is a surgical procedure with a long history dating to the beginnings of spinal surgery. (7) Poor results, high complication rates and the need for additional surgical procedures have generally diminished the enthusiasm for this procedure until recently. (6) A variety of "minimally invasive" procedures have been recently introduced that have rekindled enthusiasm for the surgical management of SIJ pathology. The technique demonstrated in the "Stabilization of the SIJ with SI-Bone" is one of these new techniques. There has been a recent publication detailing the very short term clinical outcomes with this technique that reported encouraging results. (5) In this series of 50 patients, quality of life questionnaires were available for 49 patients preoperatively, 41 patients at 3 months, 40 at 6 months and only 27 at 12 months, complicating the ability to accurately assess true outcomes. Although the focus of this video by Geisler is on the surgical technique, there should have been more information provided on the expected surgical outcomes and potential complications of SIJ fusion. (2) The video only gives minimal information on how to appropriately select patients with potential SIJ pathology for surgical intervention. There are insufficient recommendations on the clinical and radiographic follow-up needed for this procedure. A concern with this implant is whether the porous plasma spray coating on the implant actually results in bone growth across the SIJ

Shaffrey, Christopher I; Smith, Justin S

2013-07-01

311

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.

312

Some recent demographic developments in Ireland.  

PubMed

"High emigration and a familial, rural culture, isolationist and Roman Catholic in inspiration and practice, were central features of the Irish social landscape between the Famine and the Fifties. Since the 1960s, however, a social revolution has occurred. Irish marriage and fertility patterns have changed rapidly. The hegemonic rural discourse has all but disappeared and the influence of fundamentalist Catholic thinking on Irish society has weakened greatly. Irish emigration continues, but the options chosen are more varied, and many return.... Irish demography is no longer as exceptional in European or world terms as it once was. It is the timing and rapidity of the Irish demographic transition, rather than its content, which is remarkable." (EXCERPT) PMID:12233502

Einri, P M

1997-01-01

313

The Demographics of Women in Astronomy  

NASA Astrophysics Data System (ADS)

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

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

1999-12-01

314

Demographic patterns and sustainable development in Ghana.  

PubMed

There is a growing recognition that the present demographic patterns in sub-Saharan Africa, including Ghana, do not augur well for the achievement of sustainable development. Ghana is characterized by a youthful population, rapid population growth, uneven population distribution, high fertility, and rural-urban migration which has brought human numbers into collision with resources to sustain them. It is submitted that the issues discussed are equally applicable to the subregion as well. The estimated population in 1993 was about 16.4 million. The population of Ghana increased from 1970 to 1984 at a rate of growth of 2.6% per annum. The proliferation of small settlements has serious implications for sustainable development. Urban centers comprised about 12.9% of the total population in 1948, 23% in 1960, 28.3% in 1970, and 31.3% in 1984. The average woman in Ghana still has more than six children. The 1988 Ghana Demographic and Health Survey (GDHS) indicated that the median age at first marriage for women was 16.5 years. Contraceptive use is low in sub-Sahara Africa. Currently married women (15-49) currently using any modern method ranged from 1% in Burundi (1987) and Mali (1987) to 36% in Zimbabwe (1988/89). The rapid population growth in Ghana, coupled with the concentration of infrastructural facilities and job opportunities in the urban centers, has resulted in a massive rural-urban migration. Basic social facilities like health, water, housing, and electricity have been stretched to their breakpoints. The Government of Ghana initiated a major effort to put environmental issues on the priority agenda in March 1988. This led to the preparation of an Environmental Action Plan (EAP) in 1991 to address issues relating to the protection of the environment, but the need is still urgent to adopt relevant population policies as a basic strategy in sustainable development. PMID:12290510

Tawiah, E O

1995-01-01

315

Evidence for developmental plasticity in response to demographic variation in nature.  

PubMed

Adaptive developmental plasticity has been demonstrated across a number of taxa in response to variables such as photoperiod, resource abundance, and predator presence. Demographics also vary temporally and spatially within populations, but few studies have examined the possibility that developmental plasticity in response to changes in these variables can alter phenotypic distributions. Plastic responses to variable population density and sex ratio may play an important role in explaining phenotypic variation in nature. In this study, we examine two species of spiders (Nephila plumipes and Argiope keyserlingi) to examine whether there is evidence that males alter their development in response to demographics in natural populations. We studied spiders in which developing males can use pheromones as a cue of the density of conspecific males and females. We used published information about the mating systems and life history of each species to make predictions about expected patterns of plasticity in development time and correlated changes in adult body size in response to demographic variation. Within each species, male size and mass were positively correlated with the density of males but negatively correlated with the density of females, and as predicted, this was true only when calculated at spatial scales relevant to selection in each species. In contrast, seasonal variation in photoperiod could not explain measured variance in male size. Our results support the idea that developmental plasticity in response to demographics has a significant effect on phenotypic distributions in natural populations. Our results suggest that a proportion of variation in male phenotypes could be explained as a plasticity-mediated evolutionary response to variation in population demographics rather than as a physiological response to resource abundance and/or photoperiod. PMID:19739390

Kasumovic, Michael M; Bruce, Matthew J; Herberstein, Marie E; Andrade, Maydianne C B

2009-08-01

316

History Matters: The US Survey Course on the Web  

NSDL National Science Digital Library

Developed for educators, History Matters serves as an information gateway, fostering the instructional methods of American history teachers at the high school and university levels. This ripe site features historical resources in textual, graphic, and audio formats and interactive instructional modules that emphasize student analysis and interpretation of primary historical documents. Other resources available to instructors include a list of annotated syllabi, online interviews with distinguished history teachers, a searchable, annotated subject guide of relevant Websites, and Talking History, a discussion forum about teaching US History. The discussion topic changes monthly and a different prominent scholar moderates the forum each month. Currently, most content at the site covers US History from 1876 to 1946. History Matters is a joint project of the City University of New York's American Social History Project/Center for Media and Learning and George Mason University's Center for History and New Media. Note: users will need RealPlayer to listen to the oral histories.

317

Dissimilar metals joint evaluation  

NASA Technical Reports Server (NTRS)

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

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

1974-01-01

318

Distal radioulnar joint injuries  

PubMed Central

Distal radioulnar joint is a trochoid joint relatively new in evolution. Along with proximal radioulnar joint, forearm bones and interosseous membrane, it allows pronosupination and load transmission across the wrist. Injuries around distal radioulnar joint are not uncommon, and are usually associated with distal radius fractures,fractures of the ulnar styloid and with the eponymous Galeazzi or Essex_Lopresti fractures. The injury can be purely involving the soft tissue especially the triangular fibrocartilage or the radioulnar ligaments. The patients usually present with ulnar sided wrist pain, features of instability, or restriction of rotation. Difficulty in carrying loads in the hand is a major constraint for these patients. Thorough clinical examination to localize point of tenderness and appropriate provocative tests help in diagnosis. Radiology and MRI are extremely useful, while arthroscopy is the gold standard for evaluation. The treatment protocols are continuously evolving and range from conservative, arthroscopic to open surgical methods. Isolated dislocation are uncommon. Basal fractures of the ulnar styloid tend to make the joint unstable and may require operative intervention. Chronic instability requires reconstruction of the stabilizing ligaments to avoid onset of arthritis. Prosthetic replacement in arthritis is gaining acceptance in the management of arthritis. PMID:23162140

Thomas, Binu P; Sreekanth, Raveendran

2012-01-01

319

Periprosthetic Joint Infections  

PubMed Central

Implantation of joint prostheses is becoming increasingly common, especially for the hip and knee. Infection is considered to be the most devastating of prosthesis-related complications, leading to prolonged hospitalization, repeated surgical intervention, and even definitive loss of the implant. The main risk factors to periprosthetic joint infections (PJIs) are advanced age, malnutrition, obesity, diabetes mellitus, HIV infection at an advanced stage, presence of distant infectious foci, and antecedents of arthroscopy or infection in previous arthroplasty. Joint prostheses can become infected through three different routes: direct implantation, hematogenic infection, and reactivation of latent infection. Gram-positive bacteria predominate in cases of PJI, mainly Staphylococcus aureus and Staphylococcus epidermidis. PJIs present characteristic signs that can be divided into acute and chronic manifestations. The main imaging method used in diagnosing joint prosthesis infections is X-ray. Computed tomography (CT) scan may assist in distinguishing between septic and aseptic loosening. Three-phase bone scintigraphy using technetium has high sensitivity, but low specificity. Positron emission tomography using fluorodeoxyglucose (FDG-PET) presents very divergent results in the literature. Definitive diagnosis of infection should be made by isolating the microorganism through cultures on material obtained from joint fluid puncturing, surgical wound secretions, surgical debridement procedures, or sonication fluid. Success in treating PJI depends on extensive surgical debridement and adequate and effective antibiotic therapy. Treatment in two stages using a spacer is recommended for most chronic infections in arthroplasty cases. Treatment in a single procedure is appropriate in carefully selected cases. PMID:24023542

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

2013-01-01

320

Community Characteristics and Demographic Development: Three Württemberg Communities, 1558 - 1914  

E-print Network

by characteristics of the communities in which those individuals live. A project on ‘Economy, Gender, and Social Capital in the German Demographic Transition’ is analyzing the long- term determinants of fertility by carrying out family reconstitutions of three... project on ‘Economy, Gender, and Social Capital in the German Demographic Transition’ is analysing long-term fertility change in Europe over three centuries by reconstructing demographic behaviour in these three communities.1 It uses the technique...

Ogilvie, Sheilagh; Küpker, M; Maegraith, J

321

Historical demographic profiles and genetic variation of the East African Butana and Kenana indigenous dairy zebu cattle.  

PubMed

Butana and Kenana breeds from Sudan are part of the East African zebu Bos indicus type of cattle. Unlike other indigenous zebu cattle in Africa, they are unique due to their reputation for high milk production and are regarded as dairy cattle, the only ones of their kind on the African continent. In this study, we sequenced the complete mitochondrial DNA (mtDNA) D-loop of 70 animals to understand the maternal genetic variation, demographic profiles and history of the two breeds in relation to the history of cattle pastoralism on the African continent. Only taurine mtDNA sequences were identified. We found very high mtDNA diversity but low level of maternal genetic structure within and between the two breeds. Bayesian coalescent-based analysis revealed different historical and demographic profiles for the two breeds, with an earlier population expansion in the Butana vis a vis the Kenana. The maternal ancestral populations of the two breeds may have diverged prior to their introduction into the African continent, with first the arrival of the ancestral Butana population. We also reveal distinct demographic history between the two breeds with the Butana showing a decline in its effective population size (Ne ) in the recent past ~590 years. Our results provide new insights on the early history of cattle pastoralism in Sudan indicative of a large ancient effective population size. PMID:25308478

Salim, Bashir; Taha, Khalid M; Hanotte, Olivier; Mwacharo, Joram M

2014-12-01

322

Modern Latin American History History 315  

E-print Network

1 Modern Latin American History History 315 Consider Resources Primary Resources: diaries, letters popular), theses, the Web... Check subject guides: Research by Subject History Latin American Studies. Encyclopedia of Cuba: People, History, Culture REF F1754 .E53 2003 Encyclopedia of Latin American History

Abolmaesumi, Purang

323

History of Science North American Environmental History  

E-print Network

History of Science North American Environmental History Supervised by William Cronon Exam date, "A Place for Stories: Nature, History, and Narrative," The Journal of American History 78, no. 4 (1992): 1347-1376. Tim Flannery, The Eternal Frontier: An Ecological History of North America and Its

Wisconsin at Madison, University of

324

Uncovering History for Future History Teachers  

ERIC Educational Resources Information Center

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…

Fischer, Fritz

2010-01-01

325

Department of History Teaching Major in History  

E-print Network

Department of History Teaching Major in History Students interested in earning a teaching major in history must complete the requirements for a BA in history, to include the following courses: 4 credits HSTR 101 or 102 European Civilization ________ 4 credits HSTA 101 or 102 American History ________ 1

Vonessen, Nikolaus

326

WTO History Project  

NSDL National Science Digital Library

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

2001-01-01

327

Background and History of the Joint Committee's Program Evaluation Standards  

ERIC Educational Resources Information Center

It is generally thought that evaluation originated with the civil service exams that were administered in ancient China. However, modern evaluation and, of particular importance to this article, evaluation standards, originated in the United States. Why this occurred is part of a larger question about the development of social and educational…

Yarbrough, Donald B.; Shulha, Lyn M.; Caruthers, Flora

2004-01-01

328

The Joint Confidence Level Paradox: A History of Denial  

NASA Technical Reports Server (NTRS)

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

Butts, Glenn; Linton, Kent

2009-01-01

329

Volcanic Histories  

NSDL National Science Digital Library

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

Filson, Robert H.

330

Geologic History  

NSDL National Science Digital Library

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

Medina, Philip

2010-09-03

331

Turkey between two worlds: a demographic view.  

PubMed

A demographic view of Turkey is presented in this discussion. Turkey provides another example of a country, ravaged by war losses between 1914-1922, which took 4 decades, from the mid1920s to the mid1960s, to move from a pronatalist policy to an understanding of the social, economic, and most recently the political dangers of rampant population growth. The 1st census, taken in Turkey in 1927, showed a population of 13,648,270 living in an area of 299,294 square miles, substantially equal to its present dimensions. In mid1977 the population surpassed 42 million, and it reached 45.6 million in mid1980 estimates. The population grew by only 5.4% in the 1940-1945 intercensal period. With the return to normalcy following the war, Turkey's high wartime death rate (almost 40/1000 between 1940 and 1945) declined rapidly and population growth began to accelerate. It was toward the end of the 1950s that concern began to be expressed about the rapid population growth the country was experiencing. The Ministry of Health and Social Affairs and the State Planning Organization began to study the implications of the increase for future social and economic development. This reconsideration of the previous pronatalist policy, which had forbidden the dissemination of birth control supplies or information, received a stimulus following the coup of 1960 that brought the military to power. Under military rule from May 1960 to November 1961 an antinatalist position emerged and was incorporated in the 1963-1967 5 year plan and later in the Population Planning Law, No. 557, enacted in 1965. Law 557 was permissive yet essentially neutral. It did not interfere with the private decisions of couples to plan family size but it offered them contraceptive supplies and information free or at low cost as well as education in population matters. Abortion was legalized if the mother's health were endangered, but it was not allowed otherwise. Sterilization was prohibited. The implementation of these measures was spotty and subject to financial pressures. There has been a recent decline in infant mortality in recent years, but only to a figure still unacceptably high. Demographic indices confirm the existence of large and meaningful regional variations. The Turkish Demographic Survey found as early as 1966 that the crude birthrate for Istanbul and Izmir had dropped to 25/1000 but that of the Eastern Region remained as high as 50/1000 in some provinces. The differentials appear in other, refined indices such as those for age specific rates, total fertility, and completed fertility. Completed fertility was estimated in the Turkish Fertility Survey of 1978 at 6.33/woman nationwide, but with a differential of well over 2 children between urban and rural women and of a little more than 3 children between West and East. The current use of contraception is 50% overall, with a broad correlation having to do with the number of living children. PMID:12264491

Gallagher, C F

1982-01-01

332

Iran in History Iran in History  

E-print Network

1 Iran in History Iran in History by Bernard Lewis In attempting to attain some perspective on Iran in history, I begin, as I think one must, with the Arab-Islamic conquests in the seventh century--that series

Mohaghegh, Shahab

333

Clinical, Demographic, and Situational Factors Linked to Distress Associated with Benign Breast Biopsy  

PubMed Central

Few studies have examined the magnitude of distress associated with specific aspects of the benign breast biopsy (BBB) or distress risk factors. Women (n=51) completed questionnaires regarding distress associated with a recent BBB experience. Clinical and demographic risk factors for distress were also examined. All women reported distress associated with BBB; one-third reported it as “very stressful.” Biopsy-specific events were rated most distressing. Younger age, less education, non-surgical biopsy, and absence of family history of breast cancer were identified as risk factors for distress. The identified factors provide an efficient and potentially cost-effective means of stratifying risk for BBB-related distress. PMID:21240724

Steffens, Rachel F.; Wright, Heather R.; Hester, Molly Y.; Andrykowski, Michael A.

2012-01-01

334

Women and arson: a demographic study.  

PubMed

This study describes women accused of setting fires in the City of New York who were evaluated between 1980 and 1983 at the Forensic Psychiatry Clinic for the New York Criminal and Supreme Courts. Consideration is given to their age, ethnicity, history of prior mental illness, abuse of controlled substances, economic status, family background, education, and employment. Their methodology, planning, and targeting for their firesetting behavior, as well as reported motivations for engaging in arson, are also considered. PMID:3998696

Harmon, R B; Rosner, R; Wiederlight, M

1985-04-01

335

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

PubMed Central

Purpose Juvenile offenders are at heightened risk of death in adolescence and young adulthood compared to adolescents in the general population. The current study extends previous research by testing the joint contributions of distal (historical and demographic characteristics) and proximal (closer to the time of the death) predictors of mortality. We also tested and whether proximal variables were potential mediators of the effects of distal variables on mortality. Methods Participants were 1,354 serious juvenile offenders, 45 (3.32%) of whom were deceased by the completion of the study. Data were collected through self-reports and official records. Results Significant distal predictors of mortality were being African-American and having a history of substance use disorder. Proximal predictors that added significantly to prediction included gun carrying, gang membership, and substance use problems. Potential mediators of the effects of substance use disorder history were continuing substance use problems and gang membership. However, proximal variables could not explain the heightened risk for African-Americans. Conclusions Gang membership, gun carrying, and substance use problems are risk factors for early mortality among juvenile offenders, but they do not explain the elevated risk for death among African Americans. Thus, further research is needed to understand the mechanisms underlying risk for premature death among African-American adolescent offenders. Implications and contributions Findings suggest that interventions to reduce substance use problems, gang membership, and gun carrying have the potential to reduce risk of mortality for serious juvenile offenders. However, these factors cannot explain the heightened risk for death among African-American participants. PMID:23415755

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

2012-01-01

336

[On present demographic developments (author's transl)].  

PubMed

The present demographic situation in West Germany is discussed. The decrease in the population of West Germany can be attributed to the decrease in the number of marriages and the number of live births as well as the increase in the number of divorces in recent years. These tendencies are especially evident since 1970. Population models have the disadvantage of being constructed after the fact and cannot assume that a desired goal will be reached. 90% of the population of West Germany serves as employees. This, along with the increasing role of women in the work force from 1969-1976, affects marriage and birth rates. The point is reached where the state begins to play a role in order to maintain a stable level of population, usually through economic incentives. The moral aspect of such programs can not be ignored, as persons can be given a false sense of their duties by economic incentives. The importation of workers from other countries is feasible only ss long as these workers meet necessary qualifications and the domestic and foreign economic situations are favorable. PMID:761754

Maier, W

1979-02-01

337

Evolving flexible joint morphologies  

Microsoft Academic Search

Transferring virtual robotic designs into physical robots has become possible with the development of 3D printers. Accurately simulating the performance of real robots in a virtual environment requires modeling a variety of conditions, including the physical composition of the robots themselves. In this paper, we investigate how modeling material flexibility through the use of a passive joint affects the resulting

Jared M. Moore; Philip K. McKinley

2012-01-01

338

Joint Durability The problem?  

E-print Network

;Interfacial Zone? #12;Walking a Cliff Edge · In situ air content · w/cm · Saturation · Salts #12;Base Permeability #12;An Example #12;So · Water has to be prevented from saturating the concrete · Prevent water from ponding in the joint · Prevent water from penetrating from the base · Permeability of the concrete

339

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.

340

Cygnus History  

SciTech Connect

The Cygnus Dual Beam Radiographic Facility consists of two identical radiographic sources: Cygnus 1 and Cygnus 2. This Radiographic Facility is located in an underground tunnel test area at the Nevada Test Site. The sources were developed to produce high-resolution images for dynamic plutonium experiments. This work will recount and discuss salient maintenance and operational issues encountered during the history of Cygnus. A brief description of Cygnus systems and rational for design selections will set the stage for this historical narrative. It is intended to highlight the team-derived solutions for technical problems encountered during extended periods of maintenance and operation. While many of the issues are typical to pulsed power systems, some of the solutions are unique. It is hoped that other source teams will benefit from this presentation, as well as other necessary disciplines (e.g., source users, system architects, facility designers and managers, funding managers, and team leaders).

David J. Henderson, Raymond E. Gignac, Douglas E. Good, Mark D. Hansen, Charles V. Mitton; Daniel S. Nelson, Eugene C. Ormond; Steve R. Cordova, Isidro Molina; John R. Smith, Evan A. Rose

2009-07-02

341

Mapping History  

NSDL National Science Digital Library

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

2006-01-01

342

Infantile hypertrophic pyloric stenosis and asymptomatic joint hypermobility  

Microsoft Academic Search

A significant association with asymptomatic joint hypermobility was observed in 37 children with a history of infantile hypertrophic pyloric stenosis (P = .0016) and their parents (mothers, P < .0001; fathers, P < .05). The subjects with articular hypermobility showed an increased frequency of absent mandibular frenulum, thereby suggesting the presence of a previously unrecognized, systemic abnormality of the extracellular

Claudio De Felice; Giovanni Di Maggio; Paolo Toti; Stefano Parrini; Angelo Salzano; Urania E. Lagrasta; Franco Bagnoli

2001-01-01

343

Finding a Way Out of America's Demographic Dilemma  

Microsoft Academic Search

Notwithstanding the rosy short-term fiscal scenarios being advanced in Washington, the demographic transition presents the United States with a very serious fiscal crisis. In 30 years there will be twice the number of elderly, but only 15 percent more workers to help pay Social Security and Medicare benefits. A realistic reading of the government demographic projections suggests a two thirds

Laurence J. Kotlikoff; Kent Smetters; Jan Walliser

2001-01-01

344

Making the Case for Demographic Data in Extension Programming  

ERIC Educational Resources Information Center

Understanding one's community is essential for effective Extension programming across all program areas. The use of current and reliable demographic data is crucial for Extension to develop effective education and programming to track change and to uncover hidden community characteristics. We discuss what demographic data are, present…

Curtis, Katherine J.; Verdoff, Daniel; Rizzo, Bill; Beaudoin, James

2012-01-01

345

Demographic changes and economic growth: a macroeconomic projection for 2020  

Microsoft Academic Search

Exploring the economic consequences of demographic changes is often carried out within simple accounting frameworks. Such approaches consist of projecting the impact of ageing on social security expenditures under exogenous assumptions about economic growth, productivity, wages and employment. Alternative attempts to consider richer interactions between economic and demographic variables are carried out with calibrated computable general equilibrium models with overlapping

P.-O. BEFFY; J. DEROYON; N. FOURCADE; S. GREGOIR; N. LAÏB; B. MONFORT

2003-01-01

346

The Impact of Extrinsic Demographic Factors on Cantonese Speech Acquisition  

ERIC Educational Resources Information Center

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

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

2013-01-01

347

The Demographic Transition: Stages, Patterns, and Economic Implications  

Microsoft Academic Search

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

Jean-Claude Chesnais

1992-01-01

348

A Classroom Activity to Illustrate the Demographic Transition  

ERIC Educational Resources Information Center

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

Weihe, Paul

2006-01-01

349

Evaluating demographic models for goat domestication using mtdna sequences  

E-print Network

Evaluating demographic models for goat domestication using mtdna sequences Pascale GErbault demographic models for goat domestication using mtDNa sequences. Anthropozoologica 47.2 : 65-78. Routes of migration and exchange are important factors in the debate about how the Neolithic transition spread

350

The Demographic Transition and the Emergence of Sustained Economic Growth  

Microsoft Academic Search

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

Oded Galor

2005-01-01

351

Demographic Transitions and Economic Miracles in Emerging Asia  

Microsoft Academic Search

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

David E. Bloom; Jeffrey G. Williamson

1997-01-01

352

Genetic and demographic implications of aquaculture in white sturgeon (Acipenser  

E-print Network

Genetic and demographic implications of aquaculture in white sturgeon (Acipenser transmontanus (Acipenser transmontanus) populations in a river to examine the genetic and demographic trade-offs associated basé sur l'individu de populations d'esturgeons blancs (Acipenser transmontanus) dans une rivière

Jager, Henriette I.

353

Some Emerging Demographic Issues on Australia's Teaching Academic Workforce  

ERIC Educational Resources Information Center

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

Hugo, Graeme

2005-01-01

354

Demographic Faultlines: A Meta-Analysis of the Literature  

ERIC Educational Resources Information Center

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

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

2011-01-01

355

On the Scale of Global Demographic Convergence 1950-2000  

Microsoft Academic Search

The second half of the twentieth century saw global demographic change of unprecedented magnitude, with pronounced falls in both mortality and fertility in many developing countries. This article assesses the extent to which these changes have led to the convergence of demographic patterns around the world. It considers not just the levels of fertility and mortality in each country at

Chris Wilson

2001-01-01

356

Developing a Global Mindset: Integrating Demographics, Sustainability, Technology, and Globalization  

ERIC Educational Resources Information Center

Business schools face a number of challenges in responding to the business influences of demographics, sustainability, and technology--all three of which are also the fundamental driving forces for globalization. Demographic forces are creating global imbalances in worker populations and in government finances; the world economy faces…

Aggarwal, Raj

2011-01-01

357

States, demographics and competitiveness of America's best universities  

Microsoft Academic Search

Purpose – The purpose of this study is to investigate the relationship between the US News and World Report's competitive ratings of US universities with various state level demographic variables using cross-sectional data. Design\\/methodology\\/approach – Secondary data for the study were collected from the US News and World Report, Demographics USA, other US statistical sources. Regression and correlation analysis determined

A. N. M. Waheeduzzaman

2007-01-01

358

China's Demographic Challenge Requires an Integrated Coping Strategy  

ERIC Educational Resources Information Center

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

Peng, Xizhe

2013-01-01

359

Health and demographic surveillance in Sahelian mobile livestock production systems  

E-print Network

..............................................................13 1.1.5 Joint Human and animal health ("one medicine") and the concept of "One Health.2.2 Entry point of the study: evaluation of joint human and animal vaccination campaigns

Amrhein, Valentin

360

Joints in a Cornstarch Analog  

NSDL National Science Digital Library

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

Crider, Juliet

361

MIGRATION DES JOINTS DE GRAINS LA MIGRATION DES JOINTS INTERGRANULAIRES  

E-print Network

MIGRATION DES JOINTS DE GRAINS LA MIGRATION DES JOINTS INTERGRANULAIRES O. DIMITROV Centre d nombre de faits fondamentaux concernant la migration des joints de grains sont brièvement rappelés considérant les forces qui provoquent ou qui freinent la migration. L'évolution des modèles proposés pour

Boyer, Edmond

362

Decoupled Control of Flexure Jointed Hexapods Using Estimated Joint Space  

E-print Network

1 Decoupled Control of Flexure Jointed Hexapods Using Estimated Joint Space Mass-Inertia Matrix of flexure jointed hexapods (or Stewart platforms), a new decoupling method is proposed. The new decoupling. Keywords Vibration isolation, decoupling control, Stewart platform, precision robots, hexapod, symmetric

Chen, Yixin

363

Demographic processes: past, present and future - selected issues  

NASA Astrophysics Data System (ADS)

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

Fr?tczak, Ewa Zofia

2013-01-01

364

Demographic and Citation Trends in Astrophysical Journal papers and Preprints  

E-print Network

We have used data from ADS, AAS, and astro-ph, to study the publishing, preprint posting, and citation patterns for papers published in the ApJ in 1999 and 2002. This allowed us to track statistical trends in author demographics, preprint posting habits, and citation rates for ApJ papers as a whole and across various subgroups and types of ApJ papers. The most interesting results are the frequencies of use of the astro-ph server across various subdisciplines of astronomy, and the impact that such posting has on the citation history of the subsequent ApJ papers. By 2002 72% of ApJ papers were posted as astro-ph preprints, but this fraction varies from 22-95% among the subfields studied. A majority of these preprints (61%) were posted after the papers were accepted at ApJ, and 88% were posted or updated after acceptance. On average, ApJ papers posted on astro-ph are cited more than twice as often as those that are not posted on astro-ph. This difference can account for a number of other, secondary citation trends, including some of the differences in citation rates between journals and different subdisciplines. Preprints clearly have supplanted the journals as the primary means for initially becoming aware of papers, at least for a large fraction of the ApJ author community. Publication in a widely-recognized peer-reviewed journal remains as the primary determinant of the impact of a paper, however. For example, conference proceedings papers posted on astro-ph are also cited twice as frequently as those that are not posted, but overall such papers are still cited 20 times less often than the average ApJ paper. These results provide insights into how astronomical research is currently disseminated by authors and ingested by readers.

Greg J. Schwarz; Robert C. Kennicutt Jr

2004-11-10

365

HISTORY OF CONSCIOUSNESS HANDBOOK  

E-print Network

HISTORY OF CONSCIOUSNESS HANDBOOK 2012-2013 #12; 1 to Degree 12 M.A. Degree in History of Consciousness 12 #12; 2 HISTORY OF CONSCIOUSNESS HANDBOOK Welcome to graduate study in the History of Consciousness

California at Santa Cruz, University of

366

The Demographic Cost of Reproduction and Its Consequences in Balsam Fir (Abies balsamea).  

PubMed

It is an axiom of life-history theory that reproduction involves age-specific costs in terms of survival or future reproduction. The measurement of costs of reproduction in plants is difficult, and few field studies have measured these costs in terms of fitness or demographic components, thus creating a hiatus between theory and data. In this article, we describe methods for overcoming the problem, illustrated by a field study of balsam fir. We used serial correlation and a permutation test to detect growth costs of reproduction and show how these translate into demographic costs when relative tree size (and therefore growth) is critical to survival. Using chronosequences, we reconstructed the age- and size-specific dynamics of a subalpine population of Abies balsamea. A matrix model describing these dynamics was then used to estimate age- and size-specific probabilities of future survival to maturity (Zix). By using a regression model of the relationship between tree size, age, and Zix, we were able to estimate the maximum age-specific demographic cost of reproduction for trees of all ages. The shape of the age-specific cost curve for A. balsamea may explain why, contrary to a previously published hypothesis, age at first reproduction in A. balsamea does not vary between wave-regenerating and normal populations. PMID:10506547

Silvertown; Dodd

1999-09-01

367

Jaatha: a fast composite-likelihood approach to estimate demographic parameters.  

PubMed

While information about a species' demography is interesting in its own right, it is an absolute necessity for certain types of population genetic analyses. The most widely used methods to infer a species' demographic history do not take intralocus recombination or recent divergence into account, and some methods take several weeks to converge. Here, we present Jaatha, a new composite-likelihood method that does incorporate recent divergence and is also applicable when intralocus recombination rates are high. This new method estimates four demographic parameters. The accuracy of Jaatha is comparable to that of other currently available methods, although it is superior under certain conditions, especially when divergence is very recent. As a proof of concept, we apply this new method to estimate demographic parameters for two closely related wild tomato species, Solanum chilense and S. peruvianum. Our results indicate that these species likely diverged 1.44·N generations ago, where N is the effective population size of S. chilense, and that some introgression between these species continued after the divergence process initiated. Furthermore, S. peruvianum likely experienced a population expansion following speciation. PMID:21645157

Naduvilezhath, Lisha; Rose, Laura E; Metzler, Dirk

2011-07-01

368

Prevalence of Dyspepsia and its Correlation with Demographic Factors and Lifestyle in Shiraz, Southern Iran  

PubMed Central

BACKGROUND Dyspepsia is a common disorder that can present many clinical dilemmas in patient management. Although not life-threatening, the symptoms are long-lasting, interfere with daily activities and have a significant impact upon quality of life. The aim of this study was to determine prevalence of dyspepsia and its relationship with demographic and socioeconomic factors, and lifestyle in an apparently healthy population in Shiraz, southern Iran. METHODS In a population-based study, 1978 subjects aged 35 years or older were interviewed from April to September 2004. A questionnaire consisting of demographic factors, lifestyle data and gastrointestinal symptoms was completed for each participant. The validity and reliability of the questionnaire were determined. RESULTS The prevalence of dyspepsia was 29.9%. The dyspeptic patients were classified as having ulcer-like (27.9%), dysmotility-like (26.2%) or unspecified dyspepsia (45.9%). The prevalence was higher in females, water-pipe smokers, NSAIDs users, and in those with psychological distress, recurrent headache, anxiety, nightmares and past history of gastrointestinal disease. Dyspepsia had an inverse relationship with consumption of pickles, fruits and vegetables, and with duration of meal ingestion. Subjects with dyspepsia symptoms were more likely to restrict their diet, take herbal medicine, use over-the-counter drugs, consult with physicians and consume medication advised by their friends. CONCLUSION This study reveals that dyspepsia has a high prevalence in Shiraz, southern Iran and is associated with several demographic factors, lifestyle and health-seeking behavior.

Khademolhosseini, F; Mehrabani, D; Zare, N; Salehi, M; Heydari, ST; Beheshti, M; Saberi-Firoozi, M

2010-01-01

369

Prevalence of Family History of Breast, Colorectal, Prostate, and Lung Cancer in a Population-Based Study  

Microsoft Academic Search

Background: A positive family history is a known risk factor for several cancers; thus, obtaining a thorough family cancer history is essential in cancer risk evaluation and prevention management. Methods: The Family Health Study, a telephone survey in Connecticut, was conducted in 2001. A total of 1,019 participants with demographic information and family cancer history were included in this study.

P. L. Mai; L. Wideroff; M. H. Greene; B. I. Graubard

2010-01-01

370

Shoulder Joint For Protective Suit  

NASA Technical Reports Server (NTRS)

Shoulder joint allows full range of natural motion: wearer senses little or no resisting force or torque. Developed for space suit, joint offers advantages in protective garments for underwater work, firefighting, or cleanup of hazardous materials.

Kosmo, Joseph J.; Smallcombe, Richard D.

1994-01-01

371

Rolling contact orthopaedic joint design  

E-print Network

Arthroplasty, the practice of rebuilding diseased biological joints using engineering materials, is often used to treat severe arthritis of the knee and hip. Prosthetic joints have been created in a "biomimetic" manner to ...

Slocum, Alexander Henry, Jr

2013-01-01

372

Department of History Teaching Minor in History  

E-print Network

Department of History Teaching Minor in History Students interested in earning a teaching minor in history must complete the following requirements: 4 credits HSTR 101 or 102 European Civilization ________ 8 credits HSTA 101 and 102 American History ________ 1 credit HSTR 200 Introduction to Historical

Vonessen, Nikolaus

373

Temporomandibular Joint Disorders  

MedlinePLUS Videos and Cool Tools

... 2012 3 Checking the patient's dental and medical history is very important. In most cases, this provides ... Patients should avoid chewing gum, eating hard, chewy foods, and opening their mouth very wide. Heat and ...

374

Evaluating the Y chromosomal timescale in human demographic and lineage dating  

PubMed Central

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.

2014-01-01

375

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

PubMed Central

Background Habitat fragmentation has accelerated within the last century, but may have been ongoing over longer time scales. We analyzed the timing and genetic consequences of fragmentation in two isolated lake-dwelling brown trout populations. They are from the same river system (the Gudenå River, Denmark) and have been isolated from downstream anadromous trout by dams established ca. 600–800 years ago. For reference, we included ten other anadromous populations and two hatchery strains. Based on analysis of 44 microsatellite loci we investigated if the lake populations have been naturally genetically differentiated from anadromous trout for thousands of years, or have diverged recently due to the establishment of dams. Results Divergence time estimates were based on 1) Approximate Bayesian Computation and 2) a coalescent-based isolation-with-gene-flow model. Both methods suggested divergence times ca. 600–800 years bp, providing strong evidence for establishment of dams in the Medieval as the factor causing divergence. Bayesian cluster analysis showed influence of stocked trout in several reference populations, but not in the focal lake and anadromous populations. Estimates of effective population size using a linkage disequilibrium method ranged from 244 to?>?1,000 in all but one anadromous population, but were lower (153 and 252) in the lake populations. Conclusions We show that genetic divergence of lake-dwelling trout in two Danish lakes reflects establishment of water mills and impassable dams ca. 600–800 years ago rather than a natural genetic population structure. Although effective population sizes of the two lake populations are not critically low they may ultimately limit response to selection and thereby future adaptation. Our results demonstrate that populations may have been affected by anthropogenic disturbance over longer time scales than normally assumed. PMID:24903056

2014-01-01

376

Life history analysis for black bears ( Ursus americanus) in a changing demographic landscape  

Microsoft Academic Search

We used matrix population models to evaluate the relative importance of different vital rates to population growth (?) for female black bears on the Southeastern Coastal Plain (SCP) of the United States, and to determine whether reductions in subadult and adult survival due to ongoing habitat fragmentation and human disturbance will cause shifts in the relative importance of vital rates.

Adam H. Freedman; Kenneth M. Portier; Melvin E. Sunquist

2003-01-01

377

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

PubMed

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

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

2012-01-01

378

Stock structure and demographic history of the Indo-West Pacific mud crab Scylla serrata  

NASA Astrophysics Data System (ADS)

The increasing exploitation of mangrove forests, without any sustainable planning, has been seriously compromising the survival of this ecosystem and of its exclusive resources. Scylla serrata is one of the most commercially exploited crabs inhabiting mangroves and estuaries of the Indo-Pacific region. This species is extensively harvested, mainly for selling to the tourist market, and, as a consequence, its populations are in constant decline. The aim of the present study was to assess the level of genetic exchange of S. serrata within the Western Indian Ocean (WIO), using a population genetic structure approach. To achieve this goal, we reconstructed the intra-specific geographic pattern of genetic variation by partial sequencing the mitochondrial DNA cytochrome oxidase subunit I, in samples from seven mangrove sites of the WIO. Our data set then encompassed all the sequences for the same genetic marker deposited in Genbank and corresponding to samples from South East Asia, Australia and some Pacific Islands: this allowed us to estimate the level of connectivity among S. serrata populations within its distribution area. Our results show that an unique Scylla serrata metapopulation exists within the WIO; while throughout the entire Indo-Pacific region at least three distinct genetic stocks occur, corresponding to well-defined geographic regions (WIO, Eastern Australia and Pacific Ocean, North-Western Australia). South East China appears as the depositary of the most ancient haplotype and at the present time shares a haplotype with the Red Sea. The WIO populations show the signature of recent population bottlenecks, as expected for populations deeply exploited in a recent past. On the basis of our results, we can conclude that both the S. serrata populations and their habitats, i.e. mangrove forests and estuaries, of the WIO require future management and conservation regulations to avoiding overexploitation of this important key predator and marketable resource.

Fratini, Sara; Ragionieri, Lapo; Cannicci, Stefano

2010-01-01

379

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

PubMed Central

Taiwan spruce (Picea morrisonicola) is a vulnerable conifer species endemic to the island of Taiwan. A warming climate and competition from subtropical tree species has limited the range of Taiwan spruce to the higher altitudes of the island. Using seeds sampled from an area in the central mountain range of Taiwan, 15 nuclear loci were sequenced in order to measure genetic variation and to assess the long-term genetic stability of the species. Genetic diversity is low and comparable to other spruce species with limited ranges such as Picea breweriana, Picea chihuahuana, and Picea schrenkiana. Importantly, analysis using approximate Bayesian computation (ABC) provides evidence for a drastic decline in the effective population size approximately 0.3–0.5 million years ago (mya). We used simulations to show that this is unlikely to be a false-positive result due to the limited sample used here. To investigate the phylogenetic origin of Taiwan spruce, additional sequencing was performed in the Chinese spruce Picea wilsonii and combined with previously published data for three other mainland China species, Picea purpurea, Picea likiangensis, and P. schrenkiana. Analysis of population structure revealed that P. morrisonicola clusters most closely with P. wilsonii, and coalescent analyses using the program MIMAR dated the split to 4–8 mya, coincidental to the formation of Taiwan. Considering the population decrease that occurred after the split, however, led to a much more recent origin. PMID:24223271

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

2013-01-01

380

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

PubMed Central

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

Rao, Dingqi; Yang, Junxing

2012-01-01

381

The Romance of Assimilation: Studying the Demographic Outcomes of Ethnic Intermarriage in American History  

Microsoft Academic Search

Contemporary ethnic and racial intermarriage are the subject of increasing discussion in connection with America's future population; with such concerns in mind, the paper suggests a reorientation of ethnic intermarriage studies and provides related data. Yet our long record of historical experience with intermarriage, and indeed most of the discussion of contemporary trends deal with rates at one moment in

Joel Perlmann

1998-01-01

382

Demographic Outcomes of Ethnic Intermarriage in American History: Italian-Americans through Four Generations  

Microsoft Academic Search

This paper presents a new approach to measuring the extent of intermarriage among Americans of different ethnic origins. Using U.S. Census microdata and CPS data, measurements of the rates of Italian- American intermarriages across four generations are made to demonstrate that these rates were not merely high following the immigrant generation, but that even low estimates of intermarriage rates will

Joel Perlmann

2000-01-01

383

Genetic Diversity and Demographic History of Cajanus spp. Illustrated from Genome-Wide SNPs  

PubMed Central

Understanding genetic structure of Cajanus spp. is essential for achieving genetic improvement by quantitative trait loci (QTL) mapping or association studies and use of selected markers through genomic assisted breeding and genomic selection. After developing a comprehensive set of 1,616 single nucleotide polymorphism (SNPs) and their conversion into cost effective KASPar assays for pigeonpea (Cajanus cajan), we studied levels of genetic variability both within and between diverse set of Cajanus lines including 56 breeding lines, 21 landraces and 107 accessions from 18 wild species. These results revealed a high frequency of polymorphic SNPs and relatively high level of cross-species transferability. Indeed, 75.8% of successful SNP assays revealed polymorphism, and more than 95% of these assays could be successfully transferred to related wild species. To show regional patterns of variation, we used STRUCTURE and Analysis of Molecular Variance (AMOVA) to partition variance among hierarchical sets of landraces and wild species at either the continental scale or within India. STRUCTURE separated most of the domesticated germplasm from wild ecotypes, and separates Australian and Asian wild species as has been found previously. Among Indian regions and states within regions, we found 36% of the variation between regions, and 64% within landraces or wilds within states. The highest level of polymorphism in wild relatives and landraces was found in Madhya Pradesh and Andhra Pradesh provinces of India representing the centre of origin and domestication of pigeonpea respectively. PMID:24533111

Saxena, Rachit K.; von Wettberg, Eric; Upadhyaya, Hari D.; Sanchez, Vanessa; Songok, Serah; Saxena, Kulbhushan; Kimurto, Paul; Varshney, Rajeev K.

2014-01-01

384

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

PubMed

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

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

2013-09-01

385

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

PubMed

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

2014-08-01

386

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

PubMed Central

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

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

2013-01-01

387

Phylogeography and Demographic History of Amblyomma variegatum (Fabricius) (Acari: Ixodidae), the Tropical Bont Tick  

PubMed Central

Abstract The genetic diversity of Amblyomma variegatum (Fabricius) from four Caribbean islands and five African countries was compared by analyzing the sequences of three gene fragments, two mitochondrial (12SrDNA and D-Loop-DL), and one nuclear (intergenic transcribed spacer 2 [ITS2]). Genetic variability of the ITS2 DNA fragment consisted of only uninformative single nucleotide mutations, and therefore this gene was excluded from further analyses. Mitochondrial gene divergences among African populations and between Caribbean and African populations were very low. Nevertheless, the data suggest that A. variegatum is divided into distinct East and West African groups, the western group including all Caribbean samples. Phylogenetic analyses of the 12SrDNA and DL gene sequences showed that the West African A. variegatum clustered in a well-supported monophyletic clade, distinct from eastern paraphyletic lineages. Sequences of A. variegatum from the Caribbean were embedded in the West African clade, which supports the known West African historical origin for these ticks. PMID:22448720

Patel, Jaymin; Lucas-Williams, Helene; Adakal, Hassane; Kanduma, Esther G.; Tembo-Mwase, Enala; Krecek, Rosina; Mertins, James W.; Alfred, Jeffery T.; Kelly, Susyn; Kelly, Patrick

2012-01-01

388

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

PubMed

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

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

389

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

PubMed

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

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

2014-10-01

390

Ras history  

PubMed Central

Although the roots of Ras sprouted from the rich history of retrovirus research, it was the discovery of mutationally activated RAS genes in human cancer in 1982 that stimulated an intensive research effort to understand Ras protein structure, biochemistry and biology. While the ultimate goal has been developing anti-Ras drugs for cancer treatment, discoveries from Ras have laid the foundation for three broad areas of science. First, they focused studies on the origins of cancer to the molecular level, with the subsequent discovery of genes mutated in cancer that now number in the thousands. Second, elucidation of the biochemical mechanisms by which Ras facilitates signal transduction established many of our fundamental concepts of how a normal cell orchestrates responses to extracellular cues. Third, Ras proteins are also founding members of a large superfamily of small GTPases that regulate all key cellular processes and established the versatile role of small GTP-binding proteins in biology. We highlight some of the key findings of the last 28 years. PMID:21686117

2010-01-01

391

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 KingdomâÂÂs twelve public sector film archives. With support from BritainâÂÂs 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 âÂÂholiday-makingâ trips and segments from the popular British television series, âÂÂSteptoe and SonâÂÂ. 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 Pathé Film Archive.

392

Double slotted socket spherical joint  

DOEpatents

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

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

2001-05-22

393

Phase 1 Program Joint Report  

NASA Technical Reports Server (NTRS)

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

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

1999-01-01

394

The Challenges of Joint Attention  

Microsoft Academic Search

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

Frederic Kaplan; Verena V. Hafner

2004-01-01

395

Joint hypermobility syndrome pain.  

PubMed

Joint hypermobility syndrome (JHS) was initially defined as the occurrence of musculoskeletal symptoms in the presence of joint laxity and hypermobility in otherwise healthy individuals. It is now perceived as a commonly overlooked, underdiagnosed, multifaceted, and multisystemic heritable disorder of connective tissue (HDCT), which shares many of the phenotypic features of other HDCTs such as Marfan syndrome and Ehlers-Danlos syndrome. Whereas the additional flexibility can confer benefits in terms of mobility and agility, adverse effects of tissue laxity and fragility can give rise to clinical consequences that resonate far beyond the confines of the musculoskeletal system. There is hardly a clinical specialty to be found that is not touched in one way or another by JHS. Over the past decade, it has become evident that of all the complications that may arise in JHS, chronic pain is arguably the most menacing and difficult to treat. PMID:19889283

Grahame, Rodney

2009-12-01

396

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

USGS Publications Warehouse

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

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

2011-01-01

397

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

PubMed Central

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

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

2013-01-01

398

Detecting concerted demographic response across community assemblages using hierarchical approximate Bayesian computation.  

PubMed

Methods that integrate population-level sampling from multiple taxa into a single community-level analysis are an essential addition to the comparative phylogeographic toolkit. Detecting how species within communities have demographically tracked each other in space and time is important for understanding the effects of future climate and landscape changes and the resulting acceleration of extinctions, biological invasions, and potential surges in adaptive evolution. Here, we present a statistical framework for such an analysis based on hierarchical approximate Bayesian computation (hABC) with the goal of detecting concerted demographic histories across an ecological assemblage. Our method combines population genetic data sets from multiple taxa into a single analysis to estimate: 1) the proportion of a community sample that demographically expanded in a temporally clustered pulse and 2) when the pulse occurred. To validate the accuracy and utility of this new approach, we use simulation cross-validation experiments and subsequently analyze an empirical data set of 32 avian populations from Australia that are hypothesized to have expanded from smaller refugia populations in the late Pleistocene. The method can accommodate data set heterogeneity such as variability in effective population size, mutation rates, and sample sizes across species and exploits the statistical strength from the simultaneous analysis of multiple species. This hABC framework used in a multitaxa demographic context can increase our understanding of the impact of historical climate change by determining what proportion of the community responded in concert or independently and can be used with a wide variety of comparative phylogeographic data sets as biota-wide DNA barcoding data sets accumulate. PMID:24925925

Chan, Yvonne L; Schanzenbach, David; Hickerson, Michael J

2014-09-01

399

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

PubMed

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

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

2013-08-01

400

Racial, Socioeconomic, and Demographic Disparities in Access to Fertility Preservation in Young Women Diagnosed with Cancer  

PubMed Central

Background This study seeks to examine the relationship between socio-demographic characteristics and the utilization of fertility preservation services in reproductive age women diagnosed with cancer. Methods 1041 women diagnosed with cancer between age 18 and 40 responded to our retrospective survey on demographic information and reproductive health history. Five cancer types were included: leukemia, Hodgkin’s disease (HD), Non-Hodgkin Lymphoma (NHL), breast cancer, and gastrointestinal cancer (GI). 918 women reported treatment with potential to affect fertility (chemotherapy, pelvic radiation, pelvic surgery, or bone marrow transplant). Student’s t-test, linear regression, and multivariate logistic regression were used where appropriate to determine the relationship between socio-demographic characteristics and the odds of utilizing fertility preservation services. Results 61% of women were counseled on the risk of cancer treatment to fertility by the oncology team. Overall, 4% of women pursued fertility preservation. In multivariate analysis, women who had not attained a bachelor’s degree (OR 0.7, 95%CI 0.5 – 0.9) were less likely to be counseled. Trends also suggested possible disparities in access to fertility preservation with age greater than 35 years old (OR 0.1, 95% CI 0.0 – 1.4) or previous children (OR 0.3, 95% CI 0.1 – 1.1) at diagnosis. Disparities in access to fertility preservation based on ethnicity and sexual orientation were also observed. Conclusion Socio-demographic health disparities likely affect access to fertility preservation services. Although awareness of fertility preservation has improved in the last decade, an unmet need remains for reproductive health counseling and fertility preservation in reproductive age women diagnosed with cancer. PMID:22451228

Letourneau, Joseph M; Smith, James F; Ebbel, Erin E; Craig, Amaranta; Katz, Patricia P; Cedars, Marcelle I; Rosen, Mitchell P

2011-01-01

401

Joint Venture Marketing  

Microsoft Academic Search

Joint venture marketing links a for profit organization with a non-profit organization for their mutual benefit. Since American Express launched its 1981 Statue of Liberty\\/Ellis Island campaign, the strategy has proliferated among all types of health care organizations, manufacturers and even financial and educational institutions. With the successes have come concerns about non-profits having to compromise their integrity, the elimination

Nora Ganin Barnes

1991-01-01

402

Jointly Poisson processes  

Microsoft Academic Search

What constitutes jointly Poisson processes remains an unresolved issue. This\\u000areport reviews the current state of the theory and indicates how the accepted\\u000abut unproven model equals that resulting from the small time-interval limit of\\u000ajointly Bernoulli processes. One intriguing consequence of these models is that\\u000ajointly Poisson processes can only be positively correlated as measured by the\\u000acorrelation coefficient

Don H. Johnson; Ilan N. Goodman

2009-01-01

403

Prosthetic elbow joint  

NASA Technical Reports Server (NTRS)

An artificial, manually positionable elbow joint for use in an upper extremity, above-elbow, prosthetic is described. The prosthesis provides a locking feature that is easily controlled by the wearer. The instant elbow joint is very strong and durable enough to withstand the repeated heavy loadings encountered by a wearer who works in an industrial, construction, farming, or similar environment. The elbow joint of the present invention comprises a turntable, a frame, a forearm, and a locking assembly. The frame generally includes a housing for the locking assembly and two protruding ears. The forearm includes an elongated beam having a cup-shaped cylindrical member at one end and a locking wheel having a plurality of holes along a circular arc on its other end with a central bore for pivotal attachment to the protruding ears of the frame. The locking assembly includes a collar having a central opening with a plurality of internal grooves, a plurality of internal cam members each having a chamfered surface at one end and a V-shaped slot at its other end; an elongated locking pin having a crown wheel with cam surfaces and locking lugs secured thereto; two coiled compression springs; and a flexible filament attached to one end of the elongated locking pin and extending from the locking assembly for extending and retracting the locking pin into the holes in the locking wheel to permit selective adjustment of the forearm relative to the frame. In use, the turntable is affixed to the upper arm part of the prosthetic in the conventional manner, and the cup-shaped cylindrical member on one end of the forearm is affixed to the forearm piece of the prosthetic in the conventional manner. The elbow joint is easily adjusted and locked between maximum flex and extended positions.

Weddendorf, Bruce C. (inventor)

1994-01-01

404

Formation of tough composite joints  

SciTech Connect

Joints which exhibit tough fracture behavior were formed in a composite with a Si/SiC matrix reinforced with Textron SCS-6 fibers with either boron nitride or silicon nitride fiber coatings. In composites with BN coatings fibers were aligned uniaxially, while composites with Si{sub 3}N{sub 4}-coated fibers had a 0/90{degree} architecture. Lapped joints (joints with overlapping fingers) were necessary to obtain tough behavior. Geometrical requirements necessary to avoid brittle joint failure have been proposed. Joints with a simple overlap geometry (only a few fingers) would have to be very long in order to prevent brittle failure. Typical failure in these joints is caused by a crack propagating along the interfaces between the joint fingers. Joints of the same overall length, but with geometry changed to be symmetric about the joint centerline and with an extra shear surface exhibited tough fractures accompanied with extensive fiber pullout. The initial matrix cracking of these joints was relatively low because cracks propagated easily through the ends of the fingers. Joints with an optimized stepped sawtooth geometry produced composite-like failures with the stress/strain curves containing an elastic region followed by a region of rising stress with an increase of strain. Increasing the fiber/matrix interfacial strength from 9 to 25 MPa, by changing the fiber coating, increased matrix cracking and ultimate strength of the composite significantly. The best joints had matrix cracking stress and ultimate strength of 138 and 240 MPa, respectively. Joint failure was preceded by multiple matrix cracking in the entire composite. The high strength of the joints will permit building of structures containing joints with only a minor reduction of design stresses.

Brun, M.K. [GE Corporate Research and Development, Schenectady, NY (United States)

1997-05-01

405

Health & Demographic Surveillance System profile: the Muzaffarpur-TMRC Health and Demographic Surveillance System.  

PubMed

The Muzaffarpur-TMRC Health and Demographic Surveillance System (HDSS), established in 2007, was developed as an enlargement of the scope of a research collaboration on the project Visceral Leishmaniasis in Bihar, which had been ongoing since 2005. The HDSS is located in a visceral leishmaniasis (VL)-endemic area in the Muzaffarpur district of Bihar state in India. It is the only HDSS conducting research on VL, which is a vector-borne infectious disease transmitted by female phlebotomine sandflies and is fatal if left untreated. Currently the HDSS serves a population of over 105,000 in 66 villages. The HDSS collects data on vital events including pregnancies, births, deaths, migration and marriages, as well as other socio-economic indicators, at regular intervals. Incident VL cases are identified. The HDSS team is experienced in conducting both qualitative and quantitative studies, sample collection and rapid diagnostic tests in the field. In each village, volunteers connect the HDSS team with the community members. The Muzaffarpur-TMRC HDSS provides opportunities for studies on VL and other neglected tropical diseases (NTDs) and their interaction with demographic events such as migration. Queries related to research collaborations and data sharing can be sent to Dr Shyam Sundar at [drshyamsundar@hotmail.com]. PMID:25186307

Malaviya, Paritosh; Picado, Albert; Hasker, Epco; Ostyn, Bart; Kansal, Sangeeta; Singh, Rudra Pratap; Shankar, Ravi; Boelaert, Marleen; Sundar, Shyam

2014-10-01

406

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

PubMed Central

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

2010-01-01

407

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

Microsoft Academic Search

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

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

2007-01-01

408

49 CFR 213.121 - Rail joints.  

Code of Federal Regulations, 2011 CFR

...Transportation 4 2011-10-01 2011-10-01 false Rail joints. 213.121 Section 213.121 Transportation...SAFETY STANDARDS Track Structure § 213.121 Rail joints. (a) Each rail joint, insulated joint, and compromise...

2011-10-01

409

49 CFR 213.121 - Rail joints.  

Code of Federal Regulations, 2013 CFR

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

2013-10-01

410

49 CFR 213.121 - Rail joints.  

Code of Federal Regulations, 2012 CFR

...Transportation 4 2012-10-01 2012-10-01 false Rail joints. 213.121 Section 213.121 Transportation...SAFETY STANDARDS Track Structure § 213.121 Rail joints. (a) Each rail joint, insulated joint, and compromise...

2012-10-01

411

49 CFR 213.121 - Rail joints.  

Code of Federal Regulations, 2010 CFR

...Transportation 4 2010-10-01 2010-10-01 false Rail joints. 213.121 Section 213.121 Transportation...SAFETY STANDARDS Track Structure § 213.121 Rail joints. (a) Each rail joint, insulated joint, and compromise...

2010-10-01

412

Journal of Astronomical History and Heritage, 7: 53-56 (2004) The IAU Historic Radio Astronomy Working Group.  

E-print Network

Journal of Astronomical History and Heritage, 7: 53-56 (2004) The IAU Historic Radio Astronomy of publications on the history of radio astronomy; (4) monitoring other developments relating to the history of radio astronomy. This was a joint initiative of Commissions 40 (Radio Astronomy) and 41 (History

Groppi, Christopher

413

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

SciTech Connect

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

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

1992-07-01

414

Demographics of Giant Planets--Insights from Theory  

NASA Astrophysics Data System (ADS)

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

Murray-Clay, Ruth

2014-06-01

415

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

ERIC Educational Resources Information Center

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…

Kitchen, Andrew

2008-01-01

416

Relationship between child abuse history, trauma, and dissociation in Russian college students  

Microsoft Academic Search

Objective: The research was conducted to determine the relationship between violent trauma, child abuse history, and dissociative symptoms in a Russian population.Method: Three hundred and one undergraduate students from Moscow State Linguistics University participated in the study and completed the Dissociation Continuum Scale, the Violence History Questionnaire, the Traumatic Events Survey (TES), and a demographic measure.Results: Scores on dissociation and

Constance J Dalenberg; Oxana Gronskaya Palesh

2004-01-01

417

Laboratory characterization of rock joints  

SciTech Connect

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

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

1994-05-01

418

New plastic joints for plastic orthoses.  

PubMed

Plastic joints for orthoses have more advantages than metal joints. They are lightweight, noiseless comfortable to use, rust proof, corrosion free, and radiolucent. Two types of plastic joints were developed by the authors, one for the ankle joint and the other for the knee joint, elbow joint or hip joint. Polypropylene was chosen as the joint material because of its appropriate flexibility and toughness. PMID:7079105

Watanabe, H; Kutsuna, T; Morinaga, H; Okabe, T

1982-04-01

419

A phylogeographic, demographic and historical analysis of the short-tailed pit viper (Gloydius brevicaudus): evidence for early divergence and late expansion during the Pleistocene.  

PubMed

The impact of quaternary glaciation in eastern China on local fanua and flora has been a topic of considerable interest. We used mitochondrial DNA (mtDNA) sequence data and coalescent simulations to test two general biogeographic hypothesis related to the effects of Pleistocene climatic fluctuations for a widespread ophidian species (Gloydius brevicaudus) in eastern China and Korean Peninsula. The phylogenetic analysis revealed three major lineages, the southeast Coastal, Yangtze and North Lineages. The latter two are closely related and jointly form a continental lineage. Divergence dating and coalescent simulations indicate a Late Pliocene to Early Pleistocene divergence between lineages from the southeast coast and continental interior, followed by a mid-to-late Pleistocene divergence between lineages from the north and the middle-lower Yangtze Valley across East China, suggesting that all these lineages predated the last glacial maximum. An overlapping range between the two lineages within the continental lineage and a secondary contact associated with ecological transition zones on the margins of the North China Plain were also observed. These results show that vicariance patterns dominated the history of G. brevicaudus. Though the climatic events of the Pleistocene have had a marked effect on the historical distribution and intra-specific divergence of reptiles in China, coalescent and non-coalescent demographic analyses indicate that all lineages of G. brevicaudus seem not to have been adversely affected by glacial cycles during the Late Pleistocene, presumably because of an increase in the amount of climatically mild habitat in East Asia due to a decline in elevation and the development of monsoons since the Mid-End Pleistocene. PMID:21438932

Ding, Li; Gan, Xiao-Ni; He, Shun-Ping; Zhao, Er-Mi

2011-05-01

420

Form 3, 2013 Form 3: Student Demographic Information  

E-print Network

Form 3, 2013 Form 3: Student Demographic Information This form has two purposes. The first in the future. We look forward to learning about students' academic progress and their transitions into careers

Sheridan, Jennifer

421

Demographic and Social Issues of Same-Sex Adoptions  

Microsoft Academic Search

\\u000a A demographic analysis of adoption would be incomplete unless it addressed the current issue of gay males and lesbians as\\u000a adoptive parents. This chapter addresses social and demographic issues related to gay male and lesbian adoption. First, is\\u000a the background of the social, political, and psychological issues related to gay male and lesbian adoptions. Second, is the\\u000a current (as of

Mary Ann Davis

422

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

423

Joint hypermobility syndrome.  

PubMed

Although perceived as a rare condition, joint hypermobility syndrome is common. Its prevalence in rheumatology clinics is extremely high. Early estimates suggest that it may be the most common of all rheumatologic conditions. The problem lies in the general lack of awareness of the syndrome, its means of recognition, and the resultant failure to diagnose it correctly when present. It is a worldwide problem. This article provides an overview of hypermobility and hypermobility syndrome, stressing its multisystemic nature and the negative impact that it may have on quality of life, with particular reference to gastrointestinal involvement. PMID:23597972

Fikree, Asma; Aziz, Qasim; Grahame, Rodney

2013-05-01

424

Joint services electronics program  

NASA Astrophysics Data System (ADS)

This report is the Annual Progress Report for Joint Services Electronics Program Contract N00014-84-K-0327 for the Faculty of the Edward L. Ginzton Laboratory of Stanford University (S.E. Harris, Director). The report includes contributions on four units: (1) (Unit 85-1: Processor D.M. Bloom) Picosecond Optical Measurements; (2) Unit 85-2: Processor R.L. Byer) Optical and Nonlinear Optical Studies of Single Crystal Fibers; (3) (Unit 85-3: Professor G.S. Kino) Very High Frequency Signal Processing Techniques; (4) Unit 85-4: Professor C.F. Quate) Metal-Vacuum-Metal Tunneling or scanned Tunneling Microscopy.

Harris, S. E.; Bloom, D. M.; Byer, R. L.; Kino, G. S.; Quate, C. F.

1985-07-01

425

Benign joint hypermobility syndrome in soldiers; what is the effect of military training courses on associated joint instabilities?  

PubMed Central

Background: Hypermobile joints are joints with beyond normal range of motion and may be associated with joint derangements. This study aimed to evaluate the prevalence of benign joint hypermobility syndrome (BJHS) among soldiers and effect of training courses on related joint instabilities. Materials and Methods: In a prospective cohort study on 721 soldiers of Iran Army in Isfahan in 2013 the prevalence of joint hypermobility was obtained by using Beighton criteria. Soldiers divided in two groups of healthy and suffered based on their scores. The prevalence of ankle sprain, shoulder and temporomandibular joint (TMJ) dislocations identified before beginning service by history-taking and reviewing paraclinical documents. After 3 months of military training, a recent occurrence of mentioned diseases was revaluated in two groups. The collected data were analyzed using SPSS-20 software using Independent-T and Chi-square tests. Results: The frequency of BJHS before military training was 29.4%. After passing military training period, the incidence of ankle sprain was significantly higher in suffered group achieving the minimum Beighton score (BS) of 4 (4.3%, P = 0.03), 5 (5.5%, P = 0.005) and also 6 out of 9 (6.5%, P = 0.01). The incidence of TMJ dislocation was not significantly different based on a minimum score of 4, while it was higher in suffered group when considering the score of 5 (2.1%) and 6 (2.6%) for discrimination of two groups (P = 0.03). There was no significant difference between two groups in case of shoulder dislocation anyway. Conclusion: Military training can increase the incidence of ankle sprains and TMJ dislocations in hypermobility persons with higher BS in comparison with healthy people. Therefore, screening of joint hypermobility may be useful in identifying individuals at increased risk for joint instabilities. PMID:25364364

Azma, Kamran; Mottaghi, Peyman; Hosseini, Alireza; Abadi, Hossein Hassan; Nouraei, Mohammad Hadi

2014-01-01

426

Introduction: A History of “Lesbian History  

Microsoft Academic Search

This is a short history of “lesbian history,” a field of study that became explicitly possible after the 1970s and the development of lesbian-feminism. From early articles published in lesbian and feminist magazines, academic interest developed and historians began to publish journals and books on lesbian history. Frontiers and Signs produced issues on lesbian history, and groups including the London-based

Alison J. Laurie

2009-01-01

427

Pupils' Conceptions of History and History Teaching  

Microsoft Academic Search

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

Nadine Fink

428

Jointly Sponsored Research Program  

SciTech Connect

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.

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

2009-03-31

429

Joint collaborative technology experiment  

NASA Astrophysics Data System (ADS)

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.

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

430

Metal to ceramic sealed joint  

DOEpatents

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.

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

1991-01-01

431

Rotary Joint for Heat Transfer  

NASA Technical Reports Server (NTRS)

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.

Shauback, R.

1986-01-01

432

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

SciTech Connect

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.

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

1988-01-01

433

Field Museum of Natural History  

NSDL National Science Digital Library

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

434

Assessing population viability while accounting for demographic and environmental uncertainty.  

PubMed

Predicting the future trend and viability of populations is an essential task in ecology. Because many populations respond to changing environments, uncertainty surrounding environmental responses must be incorporated into population assessments. However, understanding the effects of environmental variation on population dynamics requires information on several important demographic parameters that are often difficult to estimate. Integrated population models facilitate the integration of time series data on population size and all existing demographic information from a species, allowing the estimation of demographic parameters for which limited or no empirical data exist. Although these models are ideal for assessments of population viability, they have so far not included environmental uncertainty. We incorporated environmental variation in an integrated population model to account for both demographic and environmental uncertainty in an assessment of population viability. In addition, we used this model to estimate true juvenile survival, an important demographic parameter for population dynamics that is difficult to estimate empirically. We applied this model to assess the past and future population trend of a rare island endemic songbird, the Montserrat Oriole Icterus oberi, which is threatened by volcanic activity. Montserrat Orioles experienced lower survival in years with volcanic ashfall, causing periodic population declines that were compensated by higher seasonal fecundity in years with high pre-breeding season rainfall. Due to the inclusion of both demographic and environmental uncertainty in the model, the estimated population growth rate in the immediate future was highly imprecise (95% credible interval 0.844-1.105), and the probability of extinction after three generations (in the year 2028) was low (2.1%). This projection demonstrates that accounting for both demographic and environmental sources of uncertainty provides a more realistic assessment of the viability of populations under unknown future environmental conditions. PMID:25163115

Oppel, Steffen; Hilton, Geoff; Ratcliffe, Norman; Fenton, Calvin; Daley, James; Gray, Gerard; Vickery, Juliet; Gibbons, David

2014-07-01

435

What history courses are there? History and Film Studies  

E-print Network

Essentials What history courses are there? History History and Film Studies History and Philosophy History and Politics History and Sociology American Studies and History (p33) Anthropology and History (p35) English and History (p69) What A levels/IB scores do I need? (For other qualifications

Sussex, University of

436

[Prosthetics of metacarpophalangeal joints].  

PubMed

Only a few of the large number of implants developed during the last decades for replacement of the metacarpophalangeal (MCP) joint have proven to be reliable. The rates of loosening and mechanical failure of almost all types of constrained prostheses are so high that their use cannot be recommended at present. For more than 40 years silicone arthroplasty according to Swanson has been regarded as the gold standard in the prosthetic replacement of the MCP joint. In long-term studies this device provided good pain relief and a lasting correction of preoperative ulnar deviation. The degree of patient satisfaction continues to be high after more than 10 years. With the NeuFlex spacer, a modification of the original Swanson implant, a better range of motion and a reduction of wear-related problems is expected. In this study the results of 130 NeuFlex spacers after a mean time of 3.6 years were examined and 82% of the patients were completely pain free. The mobility of the joints improved from 40 degrees preoperatively to 54 degrees after 3.6 years. Radiologically periprosthetic erosions or osteolyses were seen in approximately 15% of implants. A minimal sinking of the stems developed in 24%, a massive one in 6% and 13% of the spacers were broken. Thus the use of the NeuFlex implant resulted in a better range of motion compared to the Swanson spacer, but the problem of radiological appearance remained unchanged. For unlinked prostheses sufficient soft tissue stability is mandatory as well as wear-resistant surface materials. The pyrocarbon prosthesis according to Beckenbaugh is the only implant for which long-term results are available. In a prospective study we evaluated 28 Ascension pyrocarbon prostheses with a mean follow-up of 4 years. Stability was not found to be a problem. Subjective results were satisfactory, the range of motion remained unchanged, however 46% of prosthesis stems exhibited radiolucent seams, 7 prostheses (25%) were rated as loose and 5 of those had to be replaced by a silicone implant. Use of the implant was abandoned, as it was unreliable regarding bony fixation. There are promising concepts in some new prostheses but independent data are still lacking. PMID:17717677

Hilker, A; Miehlke, R-K; Schmidt, K

2007-09-01

437

Healthy Joints Matter What exactly is a joint?  

E-print Network

diet, avoiding injuries, and getting plenty of sleep will help you stay healthy and keep your joints be triggered by an injury to a joint, such as a knee injury that damages the cartilage. · Rheumatoid arthritis arthritis is a term often used to describe arthritis in children. Children can develop almost all types

Baker, Chris I.

438

Passive Ball Capture Joint  

NASA Technical Reports Server (NTRS)

A passive ball capture joint has a sleeve with a plurality of bores distributed about a circumference thereof and formed therethrough at an acute angle relative to the sleeve's longitudinal axis. A spring-loaded retainer is slidingly fitted in each bore and is biased such that, if allowed, will extend at least partially into the sleeve to retain a ball therein. A ring, rotatably mounted about the bores, has an interior wall defining a plurality of shaped races that bear against the spring-loaded retainers. A mechanized rotational force producer is coupled to the ring. The ring can be rotated from a first position (that presses the retainers into the sleeve to lock the ball in place) to a second position (that allows the retainers to springback out of the sleeve to release the ball).

Cloyd, Richard A. (Inventor); Bryan, Thomas C. (Inventor)

2003-01-01

439

Hominin life history: reconstruction and evolution  

PubMed Central

In this review we attempt to reconstruct the evolutionary history of hominin life history from extant and fossil evidence. We utilize demographic life history theory and distinguish life history variables, traits such as weaning, age at sexual maturity, and life span, from life history-related variables such as body mass, brain growth, and dental development. The latter are either linked with, or can be used to make inferences about, life history, thus providing an opportunity for estimating life history parameters in fossil taxa. We compare the life history variables of modern great apes and identify traits that are likely to be shared by the last common ancestor of Pan-Homo and those likely to be derived in hominins. All great apes exhibit slow life histories and we infer this to be true of the last common ancestor of Pan-Homo and the stem hominin. Modern human life histories are even slower, exhibiting distinctively long post-menopausal life spans and later ages at maturity, pointing to a reduction in adult mortality since the Pan-Homo split. We suggest that lower adult mortality, distinctively short interbirth intervals, and early weaning characteristic of modern humans are derived features resulting from cooperative breeding. We evaluate the fidelity of three life history-related variables, body mass, brain growth and dental development, with the life history parameters of living great apes. We found that body mass is the best predictor of great ape life history events. Brain growth trajectories and dental development and eruption are weakly related proxies and inferences from them should be made with caution. We evaluate the evidence of life history-related variables available for extinct species and find that prior to the transitional hominins there is no evidence of any hominin taxon possessing a body size, brain size or aspects of dental development much different from what we assume to be the primitive life history pattern for the Pan-Homo clade. Data for life history-related variables among the transitional hominin grade are consistent and none agrees with a modern human pattern. Aside from mean body mass, adult brain size, crown and root formation times, and the timing and sequence of dental eruption of Homo erectus are inconsistent with that of modern humans. Homo antecessor fossil material suggests a brain size similar to that of Homo erectus s. s., and crown formation times that are not yet modern, though there is some evidence of modern human-like timing of tooth formation and eruption. The body sizes, brain sizes, and dental development of Homo heidelbergensis and Homo neanderthalensis are consistent with a modern human life history but samples are too small to be certain that they have life histories within the modern human range. As more life history-related variable information for hominin species accumulates we are discovering that they can also have distinctive life histories that do not conform to any living model. At least one extinct hominin subclade, Paranthropus, has a pattern of dental life history-related variables that most likely set it apart from the life histories of both modern humans and chimpanzees. PMID:18380863

Robson, Shannen L; Wood, Bernard

2008-01-01

440

Endogenous technological and demographic change under increasing water scarcity  

NASA Astrophysics Data System (ADS)

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