The confounding effect of population structure on bayesian skyline plot inferences of demographic history

DEFF Research Database (Denmark)

Heller, Rasmus; Chikhi, Lounes; Siegismund, Hans

2013-01-01

Many coalescent-based methods aiming to infer the demographic history of populations assume a single, isolated and panmictic population (i.e. a Wright-Fisher model). While this assumption may be reasonable under many conditions, several recent studies have shown that the results can be misleading...... when it is violated. Among the most widely applied demographic inference methods are Bayesian skyline plots (BSPs), which are used across a range of biological fields. Violations of the panmixia assumption are to be expected in many biological systems, but the consequences for skyline plot inferences...... the best scheme for inferring demographic change over a typical time scale. Analyses of data from a structured African buffalo population demonstrate how BSP results can be strengthened by simulations. We recommend that sample selection should be carefully considered in relation to population structure...

Life history tactics shape amphibians' demographic responses to the North Atlantic Oscillation.

Science.gov (United States)

Cayuela, Hugo; Joly, Pierre; Schmidt, Benedikt R; Pichenot, Julian; Bonnaire, Eric; Priol, Pauline; Peyronel, Olivier; Laville, Mathias; Besnard, Aurélien

2017-11-01

Over the last three decades, climate abnormalities have been reported to be involved in biodiversity decline by affecting population dynamics. A growing number of studies have shown that the North Atlantic Oscillation (NAO) influences the demographic parameters of a wide range of plant and animal taxa in different ways. Life history theory could help to understand these different demographic responses to the NAO. Indeed, theory states that the impact of weather variation on a species' demographic traits should depend on its position along the fast-slow continuum. In particular, it is expected that NAO would have a higher impact on recruitment than on adult survival in slow species, while the opposite pattern is expected occur in fast species. To test these predictions, we used long-term capture-recapture datasets (more than 15,000 individuals marked from 1965 to 2015) on different surveyed populations of three amphibian species in Western Europe: Triturus cristatus, Bombina variegata, and Salamandra salamandra. Despite substantial intraspecific variation, our study revealed that these three species differ in their position on a slow-fast gradient of pace of life. Our results also suggest that the differences in life history tactics influence amphibian responses to NAO fluctuations: Adult survival was most affected by the NAO in the species with the fastest pace of life (T. cristatus), whereas recruitment was most impacted in species with a slower pace of life (B. variegata and S. salamandra). In the context of climate change, our findings suggest that the capacity of organisms to deal with future changes in NAO values could be closely linked to their position on the fast-slow continuum. © 2017 John Wiley & Sons Ltd.

Inferring the demographic history of African farmers and pygmy hunter-gatherers using a multilocus resequencing data set.

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Etienne Patin

2009-04-01

Full Text Available 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 approximately 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 approximately 60,000 years ago, followed by a split of the Pygmies' ancestors into the Western and Eastern Pygmy groups approximately 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.

Population Demographic History Can Cause the Appearance of Recombination Hotspots

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Johnston, Henry R.; Cutler, David J.

2012-01-01

Although the prevailing view among geneticists suggests that recombination hotspots exist ubiquitously across the human genome, there is only limited experimental evidence from a few genomic regions to support the generality of this claim. A small number of true recombination hotspots are well supported experimentally, but the vast majority of hotspots have been identified on the basis of population genetic inferences from the patterns of linkage disequilibrium (LD) seen in the human population. These inferences are made assuming a particular model of human history, and one of the assumptions of that model is that the effective population size of humans has remained constant throughout our history. Our results show that relaxation of the constant population size assumption can create LD and variation patterns that are qualitatively and quantitatively similar to human populations without any need to invoke localized hotspots of recombination. In other words, apparent recombination hotspots could be an artifact of variable population size over time. Several lines of evidence suggest that the vast majority of hotspots identified on the basis of LD information are unlikely to have elevated recombination rates. PMID:22560089

Demographic history and population structure of Anopheles pseudopunctipennis in Argentina based on the mitochondrial COI gene.

Science.gov (United States)

Dantur Juri, María J; Moreno, Marta; Prado Izaguirre, Mónica J; Navarro, Juan C; Zaidenberg, Mario O; Almirón, Walter R; Claps, Guillermo L; Conn, Jan E

2014-09-04

Anopheles pseudopunctipennis is an important malaria vector in the Neotropical region and the only species involved in Plasmodium transmission in the Andean foothills. Its wide geographical distribution in America, high preference for biting humans and capacity to rest inside dwellings after feeding, are attributes contributing to its vector status. Previous reports have tried to elucidate its taxonomic status, distinguishing populations from North, Central and South America. In the present study we used a mitochondrial marker to examine the demographic history of An. pseudopunctipennis in northwestern Argentina. Twelve localities were selected across 550 km of the distribution of this species in Argentina, including two near the Bolivian border and several in South Tucumán, for sampling. A fragment of the cytochrome oxidase I (COI) gene was sequenced and haplotype relationships were analyzed by a statistical parsimony network and a Neighbor-Joining (NJ) tree. Genetic differentiation was estimated with FST. Historical demographic processes were evaluated using diversity measures, neutrality tests and mismatch distribution. Forty-one haplotypes were identified, of which haplotype A was the most common and widely distributed. Neither the network nor the NJ tree showed any geographic differentiation between northern and southern populations. Haplotype diversities, Tajima's DT and Fu & Li's F and D neutrality tests and mismatch distribution supported a scenario of Holocene demographic expansion. The demographic pattern suggests that An. pseudopunctipennis has undergone a single colonization process, and the ancestral haplotype is shared by specimens from all localities, indicating mitochondrial gene flow. Genetic differentiation was minimal, observed only between one northern and one southern locality. The estimated time of the population expansion of this species was during the Holocene. These data suggest that regional vector control measures would be equally

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

KAUST Repository

Vignaud, Thomas M.

2014-10-13

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.

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

Science.gov (United States)

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

2014-11-01

For free-swimming marine species like sharks, only population genetics and demographic history analyses can be used to assess population health/status as baseline population numbers are usually unknown. We investigated the population genetics of blacktip reef sharks, Carcharhinus melanopterus; one of the most abundant reef-associated sharks and the apex predator of many shallow water reefs of the Indian and Pacific Oceans. Our sampling includes 4 widely separated locations in the Indo-Pacific and 11 islands in French Polynesia with different levels of coastal development. Four-teen microsatellite loci were analysed for samples from all locations and two mitochondrial DNA fragments, the control region and cytochrome b, were examined for 10 locations. For microsatellites, genetic diversity is higher for the locations in the large open systems of the Red Sea and Australia than for the fragmented habitat of the smaller islands of French Polynesia. Strong significant structure was found for distant locations with FST values as high as ~0.3, and a smaller but still significant structure is found within French Polynesia. Both mitochondrial genes show only a few mutations across the sequences with a dominant shared haplotype in French Polynesia and New Caledonia suggesting a common lineage different to that of East Australia. Demographic history analyses indicate population expansions in the Red Sea and Australia that may coincide with sea level changes after climatic events. Expansions and flat signals are indicated for French Polynesia as well as a significant recent bottleneck for Moorea, the most human-impacted lagoon of the locations in French Polynesia. © 2014 John Wiley & Sons Ltd.

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

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Rampersad, Sephra N; Perez-Brito, Daisy; Torres-Calzada, Claudia; Tapia-Tussell, Raul; Carrington, Christine V F

2013-06-22

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, β-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. 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; β-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. 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

Multidisciplinary perspectives on the history of human interactions with life in the ocean

DEFF Research Database (Denmark)

MacDiarmid, Alison; MacKenzie, Brian; Ojaveer, Henn

2016-01-01

-term changes of affected species and define appropriate and realistic management targets. Second, increased multi-and trans-disciplinary effort is required to better understand the relative importance of different human demographic, technological, economic, and cultural drivers on the patterns, intensities......There is an essentially circular interaction between the human social system and the marine ecosystem. The Oceans Past V Conference "Multidisciplinary perspectives on the history of human interactions with life in the ocean" held in Tallinn, Estonia, in May 2015 was an opportunity...... for the presentation and discussion of papers on a diverse array of topics that examined this socio-ecological system from a historical perspective. Here we provide background to the disciplines participating in the conference and to the conference itself. We summarize the conference papers that appear in this special...

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

KAUST Repository

Vignaud, Thomas M.; Mourier, Johann; Maynard, Jeffrey Allen; Leblois, Raphaë l; Spaet, Julia L.Y.; Clua, É ric; Neglia, Valentina; Planes, Serge

2014-01-01

For free-swimming marine species like sharks, only population genetics and demographic history analyses can be used to assess population health/status as baseline population numbers are usually unknown. We investigated the population genetics

Inferring demographic history from a spectrum of shared haplotype lengths

DEFF Research Database (Denmark)

Harris, Kelley; Nielsen, Rasmus

2013-01-01

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...

Inferring the demographic history of an oligophagous grasshopper: Effects of climatic niche stability and host-plant distribution.

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Noguerales, Víctor; Cordero, Pedro J; Ortego, Joaquín

2018-01-01

Understanding the consequences of past environmental changes on the abiotic and biotic components of the landscape and deciphering their impacts on the demographic trajectories of species is a major issue in evolutionary biogeography. In this study, we combine nuclear and mitochondrial genetic data to study the phylogeographical structure and lineage-specific demographic histories of the scrub-legume grasshopper (Chorthippus binotatus binotatus), a montane taxon distributed in the Iberian Peninsula and France that exclusively feeds on certain scrub-legume species. Genetic data and paleo-distribution modelling indicate the presence of four main lineages that seem to have diverged in allopatry and long-term persisted in Iberian and French refugia since the Mid Pleistocene. Comparisons of different demographic hypotheses in an Approximate Bayesian Computation (ABC) framework supported a population bottleneck in the northwestern French clade and paleo-distribution modelling indicate that the populations of this lineage have experienced more severe environmental fluctuations during the last 21 000 years than those from the Iberian Peninsula. Accordingly, we found that nuclear genetic diversity of the populations of scrub-legume grasshopper is positively associated with local stability of suitable habitats defined by both Pleistocene climate changes and historical distributional shifts of host-plant species. Overall, our study highlights the importance of integrating the potential effects of abiotic (i.e. climate and geography) and biotic components (i.e. inter-specific interactions) into the study of the evolutionary and demographic history of specialist taxa with narrow ecological requirements. Copyright © 2017 Elsevier Inc. All rights reserved.

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

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Fedorov, V B; Goropashnaya, A V; Boeskorov, G G; Cook, J A

2008-01-01

The association between demographic history, genealogy and geographical distribution of mitochondrial DNA cytochrome b haplotypes was studied in the wood lemming (Myopus schisticolor), a species that is closely associated with the boreal forest of the Eurasian taiga zone from Scandinavia to the Pacific coast. Except for a major phylogeographic discontinuity (0.9% nucleotide divergence) in southeastern Siberia, only shallow regional genetic structure was detected across northern Eurasia. Genetic signs of demographic expansions imply that successive range contractions and expansions on different spatial scales represented the primary historical events that shaped geographical patterns of genetic variation. Comparison of phylogeographic structure across a taxonomically diverse array of other species that are ecologically associated with the taiga forest revealed similar patterns and identified two general aspects. First, the major south-north phylogeographic discontinuity observed in five out of six species studied in southeastern Siberia and the Far East implies vicariant separation in two different refugial areas. The limited distribution range of the southeastern lineages provides no evidence of the importance of the putative southeastern refugial area for postglacial colonization of northern Eurasia by boreal forest species. Second, the lack of phylogeographic structure associated with significant reciprocal monophyly and genetic signatures of demographic expansion in all nine boreal forest animal species studied to date across most of northern Eurasia imply contraction of each species to a single refugial area during the late Pleistocene followed by range expansion on a continental scale. Similar phylogeographic patterns observed in this taxonomically diverse set of organisms with different life histories and dispersal potentials reflect the historical dynamics of their shared environment, the taiga forest in northern Eurasia.

Genetic tools link long-term demographic and life-history traits of anemonefish to their anemone hosts

KAUST Repository

Salles, Océane C.

2016-07-26

The life-history traits and population dynamics of species are increasingly being attributed to the characteristics of their preferred habitats. While coral reef fish are often strongly associated with particular habitats, long-term studies establishing the demographic and life-history consequences of occupying different reef substrata are rare and no studies have monitored individuals in situ over their lifetime and determined the fate of their offspring. Here, we documented a quasi-turnover and local reproductive success for an entire population of orange clownfish (Amphiprion percula) from Kimbe Island, Papua New Guinea, by taking bi-annual samples of DNA over a 10-yr period (2003–2013). We compared demographic and life-history traits of individuals living on two host anemone species, Heteractis magnifica and Stichodactyla gigantea, including female size, adult continued presence (a proxy for relative longevity range), early post-settlement growth, the number of eggs per clutch and ‘local’ reproductive success (defined for each adult as the number of offspring returning to the natal population). Our results indicate that while the relative longevity of adults was similar on both host anemone species, females living in H. magnifica were larger than females in S. gigantea. However, despite females growing larger and producing more eggs on H. magnifica, we found that local reproductive success was significantly higher for clownfish living in S. gigantea. Life-history traits also exhibited local spatial variation, with higher local reproductive success recorded for adults living on S. gigantea on the eastern side of the island. Our findings support a ‘silver-spoon’ hypothesis that predicts individuals that are fortunate enough to recruit into good habitat and location will be rewarded with higher long-term reproductive success and will make a disproportionate contribution to population renewal. © 2016 Springer-Verlag Berlin Heidelberg

Genome-wide Ancestry and Demographic History of African-Descendant Maroon Communities from French Guiana and Suriname.

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Fortes-Lima, Cesar; Gessain, Antoine; Ruiz-Linares, Andres; Bortolini, Maria-Cátira; Migot-Nabias, Florence; Bellis, Gil; Moreno-Mayar, J Víctor; Restrepo, Berta Nelly; Rojas, Winston; Avendaño-Tamayo, Efren; Bedoya, Gabriel; Orlando, Ludovic; Salas, Antonio; Helgason, Agnar; Gilbert, M Thomas P; Sikora, Martin; Schroeder, Hannes; Dugoujon, Jean-Michel

2017-11-02

The transatlantic slave trade was the largest forced migration in world history. However, the origins of the enslaved Africans and their admixture dynamics remain unclear. To investigate the demographic history of African-descendant Marron populations, we generated genome-wide data (4.3 million markers) from 107 individuals from three African-descendant populations in South America, as well as 124 individuals from six west African populations. Throughout the Americas, thousands of enslaved Africans managed to escape captivity and establish lasting communities, such as the Noir Marron. We find that this population has the highest proportion of African ancestry (∼98%) of any African-descendant population analyzed to date, presumably because of centuries of genetic isolation. By contrast, African-descendant populations in Brazil and Colombia harbor substantially more European and Native American ancestry as a result of their complex admixture histories. Using ancestry tract-length analysis, we detect different dates for the European admixture events in the African-Colombian (1749 CE; confidence interval [CI]: 1737-1764) and African-Brazilian (1796 CE; CI: 1789-1804) populations in our dataset, consistent with the historically attested earlier influx of Africans into Colombia. Furthermore, we find evidence for sex-specific admixture patterns, resulting from predominantly European paternal gene flow. Finally, we detect strong genetic links between the African-descendant populations and specific source populations in Africa on the basis of haplotype sharing patterns. Although the Noir Marron and African-Colombians show stronger affinities with African populations from the Bight of Benin and the Gold Coast, the African-Brazilian population from Rio de Janeiro has greater genetic affinity with Bantu-speaking populations from the Bight of Biafra and west central Africa. Copyright © 2017 American Society of Human Genetics. Published by Elsevier Inc. All rights reserved.

Inferring the demographic history from DNA sequences: An importance sampling approach based on non-homogeneous processes.

Science.gov (United States)

Ait Kaci Azzou, S; Larribe, F; Froda, S

2016-10-01

In Ait Kaci Azzou et al. (2015) we introduced an Importance Sampling (IS) approach for estimating the demographic history of a sample of DNA sequences, the skywis plot. More precisely, we proposed a new nonparametric estimate of a population size that changes over time. We showed on simulated data that the skywis plot can work well in typical situations where the effective population size does not undergo very steep changes. In this paper, we introduce an iterative procedure which extends the previous method and gives good estimates under such rapid variations. In the iterative calibrated skywis plot we approximate the effective population size by a piecewise constant function, whose values are re-estimated at each step. These piecewise constant functions are used to generate the waiting times of non homogeneous Poisson processes related to a coalescent process with mutation under a variable population size model. Moreover, the present IS procedure is based on a modified version of the Stephens and Donnelly (2000) proposal distribution. Finally, we apply the iterative calibrated skywis plot method to a simulated data set from a rapidly expanding exponential model, and we show that the method based on this new IS strategy correctly reconstructs the demographic history. Copyright © 2016. Published by Elsevier Inc.

Region-wide and ecotype-specific differences in demographic histories of threespine stickleback populations, estimated from whole genome sequences.

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Liu, Shenglin; Hansen, Michael M; Jacobsen, Magnus W

2016-10-01

We analysed 81 whole genome sequences of threespine sticklebacks from Pacific North America, Greenland and Northern Europe, representing 16 populations. Principal component analysis of nuclear SNPs grouped populations according to geographical location, with Pacific populations being more divergent from each other relative to European and Greenlandic populations. Analysis of mitogenome sequences showed Northern European populations to represent a single phylogeographical lineage, whereas Greenlandic and particularly Pacific populations showed admixture between lineages. We estimated demographic history using a genomewide coalescence with recombination approach. The Pacific populations showed gradual population expansion starting >100 Kya, possibly reflecting persistence in cryptic refuges near the present distributional range, although we do not rule out possible influence of ancient admixture. Sharp population declines ca. 14-15 Kya were suggested to reflect founding of freshwater populations by marine ancestors. In Greenland and Northern Europe, demographic expansion started ca. 20-25 Kya coinciding with the end of the Last Glacial Maximum. In both regions, marine and freshwater populations started to show different demographic trajectories ca. 8-9 Kya, suggesting that this was the time of recolonization. In Northern Europe, this estimate was surprisingly late, but found support in subfossil evidence for presence of several freshwater fish species but not sticklebacks 12 Kya. The results demonstrate distinctly different demographic histories across geographical regions with potential consequences for adaptive processes. They also provide empirical support for previous assumptions about freshwater populations being founded independently from large, coherent marine populations, a key element in the Transporter Hypothesis invoked to explain the widespread occurrence of parallel evolution across freshwater stickleback populations. © 2016 John Wiley & Sons Ltd.

Contrasting patterns of population structure and demographic history in cryptic species of Bostrychia intricata (Rhodomelaceae, Rhodophyta) from New Zealand.

Science.gov (United States)

Muangmai, Narongrit; Fraser, Ceridwen I; Zuccarello, Giuseppe C

2015-06-01

Spatial patterns of genetic diversity provide insight into the demography and history of species. Morphologically similar but genetically distinct "cryptic" species are increasingly being recognized in marine organisms through molecular analyses. Such species are, on closer inspection, often discovered to display contrasting life histories or occasionally minor morphological differences; molecular tools can thus be useful indicators of diversity. Bostrychia intricata, a marine red alga, is widely distributed throughout the Southern Hemisphere and comprises many cryptic species. We used mitochondrial cytochrome c oxidase I gene sequences to assess the genetic variation, population genetic structure, and demographic history of B. intricata in New Zealand. Our results supported the existence of three cryptic species of B. intricata (N2, N4, and N5) in New Zealand. Cryptic species N4, which was found throughout New Zealand, showed a higher genetic diversity and wider distribution than the other two species, which were only found in the North Island and northern South Island. Our analyses showed low to moderate genetic differentiation among eastern North Island populations for cryptic species N2, but high differentiation among North and South Island populations for N4, suggesting different population structure between these cryptic species. Data also indicated that N2 has recently undergone population expansion, probably since the Last Glacial Maximum (LGM), while the higher genetic diversity in N4 populations suggests persistence in situ through the LGM. The contrasting population structures and inferred demographic histories of these species highlight that life history can vary greatly even among morphologically indistinguishable taxa. © 2015 Phycological Society of America.

Genome - wide variation and demographic history of small cats with a focus on Felis species

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Anubhab Khan

2017-10-01

Full Text Available Majority of the 38 known cat species are classified as small and they inhabit five of the seven continents. They survive in a vast range of habitats but still 12 out of the 18 threatened felids are small cats. However, there has not been enough progress in the field of small cat research as they generally get overshadowed by the charismatic big cats. Here we attempt to create a resource for small cat research especially of the genus Felis which has six species out of which two are classified as vulnerable by IUCN and at least one more is at risk. We collected tissue samples of four Felis chaus (Jungle cat from central India and used available whole genome sequences of nine individuals from four other Felis species, two individuals of Prionailurus bengalensis and an Otocolobus manul. These whole genome sequences were filtered and aligned with the already published domestic cat (Felis catus genome assembly. Felids are closely related species and reads from all species in our study aligned with the domestic cat genome with a rate of at least 93%. We estimated the existing genomic variation by calculating heterozygous SNP encounter rate. So far, it seems that all wild cats have more genetic variation than Felis catus species. This can be attributed to the inbreeding in these cats. Among the wild cats, Felis silvestris seems to have the highest level of genetic variation. To understand the reasons behind the distribution of genetic variation in small cats, we estimated the demographic histories of each of the species using PSMC. This method can only detect demographic changes more than 1000 generations ago. We observe that roughly all species share a parallel history in terms of population increase. The most interesting and important feature might be that all wild small cat population sizes increased exponentially around twenty thousand years ago as opposed to domestic cat and big cats which declined around this time. Another interesting feature of

Demographic and human dimension of international migration in Ukraine

OpenAIRE

Duhinets H. V.; Rielina I. Ie.

2015-01-01

Modern transformation of the economic system of this country led to structural changes in the social environment. Movement of population and human resources inside and outside the country increased. The growth of the scale of international migration processes, their mixed impact on the development of the countries, qualitative transformation of the specified processes determine the importance of the study of demographic and employment dimension of the international migration processes in Ukra...

The Socio-Demographic Changes in Romania: an Analysis from the Human Development Perspective

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Mioara BORZA

2017-06-01

Full Text Available The social and demographic changes registered in recent years, at European and Romanian level, have produced some effects visible in various reference areas. By this paper, we propose to achieve an empirical analysis meant to emphasize the main socio-economic changes of the last 10 years and their influence on the human society development. Based on the inventory of statistical data referring to the socio-demographic dynamics and using a research methodology based on inductive reasoning, dynamic and dialectics analysis, we will obtain some results of research that indicate: the human development is in positive evolution, even the number of population is decreasing.

Revolutions in energy input and material cycling in Earth history and human history

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Lenton, Timothy M.; Pichler, Peter-Paul; Weisz, Helga

2016-04-01

Major revolutions in energy capture have occurred in both Earth and human history, with each transition resulting in higher energy input, altered material cycles and major consequences for the internal organization of the respective systems. In Earth history, we identify the origin of anoxygenic photosynthesis, the origin of oxygenic photosynthesis, and land colonization by eukaryotic photosynthesizers as step changes in free energy input to the biosphere. In human history we focus on the Palaeolithic use of fire, the Neolithic revolution to farming, and the Industrial revolution as step changes in free energy input to human societies. In each case we try to quantify the resulting increase in energy input, and discuss the consequences for material cycling and for biological and social organization. For most of human history, energy use by humans was but a tiny fraction of the overall energy input to the biosphere, as would be expected for any heterotrophic species. However, the industrial revolution gave humans the capacity to push energy inputs towards planetary scales and by the end of the 20th century human energy use had reached a magnitude comparable to the biosphere. By distinguishing world regions and income brackets we show the unequal distribution in energy and material use among contemporary humans. Looking ahead, a prospective sustainability revolution will require scaling up new renewable and decarbonized energy technologies and the development of much more efficient material recycling systems - thus creating a more autotrophic social metabolism. Such a transition must also anticipate a level of social organization that can implement the changes in energy input and material cycling without losing the large achievements in standard of living and individual liberation associated with industrial societies.

Disentangling the effects of demography and selection in human history.

Science.gov (United States)

Stajich, Jason E; Hahn, Matthew W

2005-01-01

Demographic events affect all genes in a genome, whereas natural selection has only local effects. Using publicly available data from 151 loci sequenced in both European-American and African-American populations, we attempt to distinguish the effects of demography and selection. To analyze large sets of population genetic data such as this one, we introduce "Perlymorphism," a Unix-based suite of analysis tools. Our analyses show that the demographic histories of human populations can account for a large proportion of effects on the level and frequency of variation across the genome. The African-American population shows both a higher level of nucleotide diversity and more negative values of Tajima's D statistic than does a European-American population. Using coalescent simulations, we show that the significantly negative values of the D statistic in African-Americans and the positive values in European-Americans are well explained by relatively simple models of population admixture and bottleneck, respectively. Working within these nonequilibrium frameworks, we are still able to show deviations from neutral expectations at a number of loci, including ABO and TRPV6. In addition, we show that the frequency spectrum of mutations--corrected for levels of polymorphism--is correlated with recombination rate only in European-Americans. These results are consistent with repeated selective sweeps in non-African populations, in agreement with recent reports using microsatellite data.

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

Science.gov (United States)

Faria, Rui; Weiss, Steven; Alexandrino, Paulo

2012-09-30

Atlantic was detected but not in the opposite direction, with colonization of the North Atlantic probably occurring after last glacial maximum. The similar haplotype network topologies between the two species support a common intraspecific history of isolation. Despite these similarities, A. alosa and A. fallax have clearly responded differently to the hydrological dynamics of the Pleistocene, as reflected in their distinct demographic histories. As the species additionally occupy different ecological niches it should not be surprising that they differ in resilience to natural or human-mediated climatic changes. For A. fallax, it is further clear that its demographic response to large-scale hydrological events is not synchronized between the Atlantic and Mediterranean basins. These regional and species-specific differences should be incorporated into future predictive modeling of biological response to climate change as well as current management concepts.

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

Directory of Open Access Journals (Sweden)

Faria Rui

2012-09-01

. fallax, migration from the Mediterranean to the Atlantic was detected but not in the opposite direction, with colonization of the North Atlantic probably occurring after last glacial maximum. Conclusion The similar haplotype network topologies between the two species support a common intraspecific history of isolation. Despite these similarities, A. alosa and A. fallax have clearly responded differently to the hydrological dynamics of the Pleistocene, as reflected in their distinct demographic histories. As the species additionally occupy different ecological niches it should not be surprising that they differ in resilience to natural or human-mediated climatic changes. For A. fallax, it is further clear that its demographic response to large-scale hydrological events is not synchronized between the Atlantic and Mediterranean basins. These regional and species-specific differences should be incorporated into future predictive modeling of biological response to climate change as well as current management concepts.

Fire history reflects human history in the Pine Creek Gorge of north-central Pennsylvania

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Patrick H. Brose; Richard P. Guyette; Joseph M. Marschall; Michael C. Stambaugh

2015-01-01

Fire history studies are important tools for understanding past fire regimes and the roles humans played in those regimes. Beginning in 2010, we conducted a fire history study in the Pine Creek Gorge area of north-central Pennsylvania to ascertain the number of fires and fire-free intervals, their variability through time, and the role of human influences. We collected...

Formal linguistics as a cue to demographic history.

Science.gov (United States)

Longobardi, Giuseppe; Ceolin, Andrea; Ecay, Aaron; Ghirotto, Silvia; Guardiano, Cristina; Irimia, Monica-Alexandrina; Michelioudakis, Dimitris; Radkevich, Nina; Pettener, Davide; Luiselli, Donata; Barbujani, Guido

2016-06-20

Beyond its theoretical success, the development of molecular genetics has brought about the possibility of extraordinary progress in the study of classification and in the inference of the evolutionary history of many species and populations. A major step forward was represented by the availability of extremely large sets of molecular data suited to quantitative and computational treatments. In this paper, we argue that even in cognitive sciences, purely theoretical progress in a discipline such as linguistics may have analogous impact. Thus, exactly on the model of molecular biology, we propose to unify two traditionally unrelated lines of linguistic investigation: 1) the formal study of syntactic variation (parameter theory) in the biolinguistic program; 2) the reconstruction of relatedness among languages (phylogenetic taxonomy). The results of our linguistic analysis have thus been plotted against data from population genetics and the correlations have turned out to be largely significant: given a non-trivial set of languages/populations, the description of their variation provided by the comparison of systematic parametric analysis and molecular anthropology informatively recapitulates their history and relationships. As a result, we can claim that the reality of some parametric model of the language faculty and language acquisition/transmission (more broadly of generative grammar) receives strong and original support from its historical heuristic power. Then, on these grounds, we can begin testing Darwin's prediction that, when properly generated, the trees of human populations and of their languages should eventually turn out to be significantly parallel.

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

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

2013-01-01

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

The demographics of human and malaria movement and migration patterns in East Africa.

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Pindolia, Deepa K; Garcia, Andres J; Huang, Zhuojie; Smith, David L; Alegana, Victor A; Noor, Abdisalan M; Snow, Robert W; Tatem, Andrew J

2013-11-05

The quantification of parasite movements can provide valuable information for control strategy planning across all transmission intensities. Mobile parasite carrying individuals can instigate transmission in receptive areas, spread drug resistant strains and reduce the effectiveness of control strategies. The identification of mobile demographic groups, their routes of travel and how these movements connect differing transmission zones, potentially enables limited resources for interventions to be efficiently targeted over space, time and populations. National population censuses and household surveys provide individual-level migration, travel, and other data relevant for understanding malaria movement patterns. Together with existing spatially referenced malaria data and mathematical models, network analysis techniques were used to quantify the demographics of human and malaria movement patterns in Kenya, Uganda and Tanzania. Movement networks were developed based on connectivity and magnitudes of flow within each country and compared to assess relative differences between regions and demographic groups. Additional malaria-relevant characteristics, such as short-term travel and bed net use, were also examined. Patterns of human and malaria movements varied between demographic groups, within country regions and between countries. Migration rates were highest in 20-30 year olds in all three countries, but when accounting for malaria prevalence, movements in the 10-20 year age group became more important. Different age and sex groups also exhibited substantial variations in terms of the most likely sources, sinks and routes of migration and malaria movement, as well as risk factors for infection, such as short-term travel and bed net use. Census and survey data, together with spatially referenced malaria data, GIS and network analysis tools, can be valuable for identifying, mapping and quantifying regional connectivities and the mobility of different demographic

The demographic transition influences variance in fitness and selection on height and BMI in rural Gambia.

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

2013-05-20

Recent human history is marked by demographic transitions characterized by declines in mortality and fertility. By influencing the variance in those fitness components, demographic transitions can affect selection on other traits. 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. 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. Copyright © 2013 Elsevier Ltd. All rights reserved.

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

DEFF Research Database (Denmark)

Zhao, Shancen; Zheng, Pingping; Dong, Shanshan

2013-01-01

The panda lineage dates back to the late Miocene and ultimately leads to only one extant species, the giant panda (Ailuropoda melanoleuca). Although global climate change and anthropogenic disturbances are recognized to shape animal population demography their contribution to panda population...... dynamics remains largely unknown. We sequenced the whole genomes of 34 pandas at an average 4.7-fold coverage and used this data set together with the previously deep-sequenced panda genome to reconstruct a continuous demographic history of pandas from their origin to the present. We identify two...... panda populations that show genetic adaptation to their environments. However, in all three populations, anthropogenic activities have negatively affected pandas for 3,000 years....

What we can and cannot learn from the history of world population.

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Livi-Bacci, Massimo

2015-01-01

Mankind is passing through an exceptional phase of accelerated population growth that generates anxiety about the future. How many billion people will share the limited resources of our globe a century from now? What will be the consequences of globalization for human behaviour? How will individuals react to emerging new constraints? What will be the consequences of climate change for human society? Obviously enough, history cannot offer operational answers to these crucial questions. Nevertheless, history offers some interesting insights into demographic behaviour experienced in the past that could be replicated in the future, with the variations and adaptations dictated by the changing contexts. In other words, there are constants and structures in human behaviour, and there are robust mechanisms in the functioning of demographic systems that are of some help in preparing us to deal with the future.

A genetic atlas of human admixture history.

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Hellenthal, Garrett; Busby, George B J; Band, Gavin; Wilson, James F; Capelli, Cristian; Falush, Daniel; Myers, Simon

2014-02-14

Modern genetic data combined with appropriate statistical methods have the potential to contribute substantially to our understanding of human history. We have developed an approach that exploits the genomic structure of admixed populations to date and characterize historical mixture events at fine scales. We used this to produce an atlas of worldwide human admixture history, constructed by using genetic data alone and encompassing over 100 events occurring over the past 4000 years. We identified events whose dates and participants suggest they describe genetic impacts of the Mongol empire, Arab slave trade, Bantu expansion, first millennium CE migrations in Eastern Europe, and European colonialism, as well as unrecorded events, revealing admixture to be an almost universal force shaping human populations.

Archaic admixture in human history.

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Wall, Jeffrey D; Yoshihara Caldeira Brandt, Debora

2016-12-01

Modern humans evolved in Southern or Eastern Africa, and spread from there across the rest of the world. As they expanded across Africa and Eurasia, they encountered other hominin groups. The extent to which modern and 'archaic' human groups interbred is an area of active research, and while we know that modern humans interbred with Neanderthals and Denisovans, there is not yet agreement on how many admixture events there were or on how much Neanderthal or Denisovan DNA can be found in contemporary genomes. Here we review what is known about archaic admixture in human history, with a focus on what has been discovered in the past 2 years. Copyright © 2016 Elsevier Ltd. All rights reserved.

Genetic diversity, outcrossing rate, and demographic history along a climatic gradient in the ruderal plant Ruellia nudiflora (Acanthaceae)

OpenAIRE

Vargas-Mendoza, Carlos F.; Ortegón-Campos, Ilka; Marrufo-Zapata, Denis; Herrera, Carlos M.; Parra-Tabla, Víctor

2015-01-01

Ruellia nudiflora has shown a high potential to easily invade disturbed areas. Outcrossing rate and genetic structure and diversity in this species were examined along a climatic gradient in the Yucatán Peninsula (Mexico) in order to understand the effects of environmental heterogeneity - isolation by environment (IBE) - as well as correlation in herkogamy on genetic structure, diversity, and demographic history in this species. Nine populations were sampled along a temperature-precipitation ...

A genetic atlas of human admixture history

Science.gov (United States)

Hellenthal, Garrett; Busby, George B.J.; Band, Gavin; Wilson, James F.; Capelli, Cristian

2014-01-01

Modern genetic data combined with appropriate statistical methods have the potential to contribute substantially to our understanding of human history. We have developed an approach that exploits the genomic structure of admixed populations to date and characterize historical mixture events at fine scales. We used this to produce an atlas of worldwide human admixture history, constructed using genetic data alone and encompassing over 100 events occurring over the past 4,000 years. We identify events whose dates and participants suggest they describe genetic impacts of the Mongol Empire, Arab slave trade, Bantu expansion, first millennium CE migrations in eastern Europe, and European colonialism, as well as unrecorded events, revealing admixture to be an almost universal force shaping human populations. PMID:24531965

The History of Human Freedom and Dignity in Western Civilization

DEFF Research Database (Denmark)

Jacobsen, Anders-Christian

2016-01-01

Kort introduktion til et europæisk forskningsprojekt "The History of Human Freedom and Dignity in Western Civilisation'......Kort introduktion til et europæisk forskningsprojekt "The History of Human Freedom and Dignity in Western Civilisation'...

Robust Demographic Inference from Genomic and SNP Data

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Excoffier, Laurent; Dupanloup, Isabelle; Huerta-Sánchez, Emilia; Sousa, Vitor C.; Foll, Matthieu

2013-01-01

We introduce a flexible and robust simulation-based framework to infer demographic parameters from the site frequency spectrum (SFS) computed on large genomic datasets. We show that our composite-likelihood approach allows one to study evolutionary models of arbitrary complexity, which cannot be tackled by other current likelihood-based methods. For simple scenarios, our approach compares favorably in terms of accuracy and speed with , the current reference in the field, while showing better convergence properties for complex models. We first apply our methodology to non-coding genomic SNP data from four human populations. To infer their demographic history, we compare neutral evolutionary models of increasing complexity, including unsampled populations. We further show the versatility of our framework by extending it to the inference of demographic parameters from SNP chips with known ascertainment, such as that recently released by Affymetrix to study human origins. Whereas previous ways of handling ascertained SNPs were either restricted to a single population or only allowed the inference of divergence time between a pair of populations, our framework can correctly infer parameters of more complex models including the divergence of several populations, bottlenecks and migration. We apply this approach to the reconstruction of African demography using two distinct ascertained human SNP panels studied under two evolutionary models. The two SNP panels lead to globally very similar estimates and confidence intervals, and suggest an ancient divergence (>110 Ky) between Yoruba and San populations. Our methodology appears well suited to the study of complex scenarios from large genomic data sets. PMID:24204310

Multiple Sclerosis and Several Demographic Characteristics, Family History of MS, and Month of Birth: A Case-Control Study

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Bagheri

2015-09-01

Full Text Available Background Several factors have been reported as risk factors for multiple sclerosis (MS; however, the main causes of the disease are still unknown. A geographical area with a low MS incidence is Ahvaz, Iran. Objectives The objective of this study was to evaluate the association of several demographic characteristics, family history, and birth month with MS in Ahvaz. Patients and Methods This was a case-control study including 155 MS cases and 155 controls matched for age, sex, and residential status. The participants were selected randomly, using a systematic method, from the MS patients referred to the MS Society of Khuzestan (Iran. The data collection tool was a standardized questionnaire designed by the authors to assess demographic characteristics. Data were analyzed using descriptive statistics including mean, frequency, and standard deviation and inferential statistical tests including χ2, Fisher’s exact test, and logistic regression using SPSS version 19. Results In both cases and controls, no significant associations were found between Arab ethnicity and incidence of MS, marital status and risk of MS in Ahvaz, or more than 15-year residency in Ahvaz, birth in Khuzestan, and month of birth and the risk of MS (P > 0.05. However, there was a marginally significant association between living from birth to age 15 years in Ahvaz and MS (P = 0.05. Furthermore, there was an association between a family history of MS and the risk of MS in Ahvaz (P = 0.02, which was significant in univariate logistic regression (P = 0.006. Conclusions The findings suggested that according to the ecological conditions of Ahvaz, a family history of MS may increase the risk of developing MS.

Urbanization shapes the demographic history of a native rodent (the white-footed mouse, Peromyscus leucopus) in New York City

OpenAIRE

Harris, Stephen E.; Xue, Alexander T.; Alvarado-Serrano, Diego; Boehm, Joel T.; Joseph, Tyler; Hickerson, Michael J.; Munshi-South, Jason

2016-01-01

How urbanization shapes population genomic diversity and evolution of urban wildlife is largely unexplored. We investigated the impact of urbanization on white-footed mice, Peromyscus leucopus, in the New York City (NYC) metropolitan area using coalescent-based simulations to infer demographic history from the site-frequency spectrum. We assigned individuals to evolutionary clusters and then inferred recent divergence times, population size changes and migration using genome-wide single nucle...

Current demographics suggest future energy supplies will be inadequate to slow human population growth.

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John P DeLong

Full Text Available Influential demographic projections suggest that the global human population will stabilize at about 9-10 billion people by mid-century. These projections rest on two fundamental assumptions. The first is that the energy needed to fuel development and the associated decline in fertility will keep pace with energy demand far into the future. The second is that the demographic transition is irreversible such that once countries start down the path to lower fertility they cannot reverse to higher fertility. Both of these assumptions are problematic and may have an effect on population projections. Here we examine these assumptions explicitly. Specifically, given the theoretical and empirical relation between energy-use and population growth rates, we ask how the availability of energy is likely to affect population growth through 2050. Using a cross-country data set, we show that human population growth rates are negatively related to per-capita energy consumption, with zero growth occurring at ∼13 kW, suggesting that the global human population will stop growing only if individuals have access to this amount of power. Further, we find that current projected future energy supply rates are far below the supply needed to fuel a global demographic transition to zero growth, suggesting that the predicted leveling-off of the global population by mid-century is unlikely to occur, in the absence of a transition to an alternative energy source. Direct consideration of the energetic constraints underlying the demographic transition results in a qualitatively different population projection than produced when the energetic constraints are ignored. We suggest that energetic constraints be incorporated into future population projections.

Current demographics suggest future energy supplies will be inadequate to slow human population growth.

Science.gov (United States)

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

2010-10-05

Influential demographic projections suggest that the global human population will stabilize at about 9-10 billion people by mid-century. These projections rest on two fundamental assumptions. The first is that the energy needed to fuel development and the associated decline in fertility will keep pace with energy demand far into the future. The second is that the demographic transition is irreversible such that once countries start down the path to lower fertility they cannot reverse to higher fertility. Both of these assumptions are problematic and may have an effect on population projections. Here we examine these assumptions explicitly. Specifically, given the theoretical and empirical relation between energy-use and population growth rates, we ask how the availability of energy is likely to affect population growth through 2050. Using a cross-country data set, we show that human population growth rates are negatively related to per-capita energy consumption, with zero growth occurring at ∼13 kW, suggesting that the global human population will stop growing only if individuals have access to this amount of power. Further, we find that current projected future energy supply rates are far below the supply needed to fuel a global demographic transition to zero growth, suggesting that the predicted leveling-off of the global population by mid-century is unlikely to occur, in the absence of a transition to an alternative energy source. Direct consideration of the energetic constraints underlying the demographic transition results in a qualitatively different population projection than produced when the energetic constraints are ignored. We suggest that energetic constraints be incorporated into future population projections.

Rethinking the history of common walnut (Juglans regia L.) in Europe: Its origins and human interactions.

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Pollegioni, Paola; Woeste, Keith; Chiocchini, Francesca; Del Lungo, Stefano; Ciolfi, Marco; Olimpieri, Irene; Tortolano, Virginia; Clark, Jo; Hemery, Gabriel E; Mapelli, Sergio; Malvolti, Maria Emilia

2017-01-01

Common walnut (Juglans regia L) is an economically important species cultivated worldwide for its high-quality wood and nuts. It is generally accepted that after the last glaciation J. regia survived and grew in almost completely isolated stands in Asia, and that ancient humans dispersed walnuts across Asia and into new habitats via trade and cultural expansion. The history of walnut in Europe is a matter of debate, however. In this study, we estimated the genetic diversity and structure of 91 Eurasian walnut populations using 14 neutral microsatellites. By integrating fossil pollen, cultural, and historical data with population genetics, and approximate Bayesian analysis, we reconstructed the demographic history of walnut and its routes of dispersal across Europe. The genetic data confirmed the presence of walnut in glacial refugia in the Balkans and western Europe. We conclude that human-mediated admixture between Anatolian and Balkan walnut germplasm started in the Early Bronze Age, and between western Europe and the Balkans in eastern Europe during the Roman Empire. A population size expansion and subsequent decline in northeastern and western Europe was detected in the last five centuries. The actual distribution of walnut in Europe resulted from the combined effects of expansion/contraction from multiple refugia after the Last Glacial Maximum and its human exploitation over the last 5,000 years.

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

Science.gov (United States)

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

2012-09-01

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

Genomic Analyses Reveal Demographic History and Temperate Adaptation of the Newly Discovered Honey Bee Subspecies Apis mellifera sinisxinyuan n. ssp.

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Chen, Chao; Liu, Zhiguang; Pan, Qi; Chen, Xiao; Wang, Huihua; Guo, Haikun; Liu, Shidong; Lu, Hongfeng; Tian, Shilin; Li, Ruiqiang; Shi, Wei

2016-05-01

Studying the genetic signatures of climate-driven selection can produce insights into local adaptation and the potential impacts of climate change on populations. The honey bee (Apis mellifera) is an interesting species to study local adaptation because it originated in tropical/subtropical climatic regions and subsequently spread into temperate regions. However, little is known about the genetic basis of its adaptation to temperate climates. Here, we resequenced the whole genomes of ten individual bees from a newly discovered population in temperate China and downloaded resequenced data from 35 individuals from other populations. We found that the new population is an undescribed subspecies in the M-lineage of A. mellifera (Apis mellifera sinisxinyuan). Analyses of population history show that long-term global temperature has strongly influenced the demographic history of A. m. sinisxinyuan and its divergence from other subspecies. Further analyses comparing temperate and tropical populations identified several candidate genes related to fat body and the Hippo signaling pathway that are potentially involved in adaptation to temperate climates. Our results provide insights into the demographic history of the newly discovered A. m. sinisxinyuan, as well as the genetic basis of adaptation of A. mellifera to temperate climates at the genomic level. These findings will facilitate the selective breeding of A. mellifera to improve the survival of overwintering colonies. © The Author 2016. Published by Oxford University Press on behalf of the Society for Molecular Biology and Evolution.

Accounting for rate variation among lineages in comparative demographic analyses

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

2014-01-01

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

On the Psychometric Study of Human Life History Strategies.

Science.gov (United States)

Richardson, George B; Sanning, Blair K; Lai, Mark H C; Copping, Lee T; Hardesty, Patrick H; Kruger, Daniel J

2017-01-01

This article attends to recent discussions of validity in psychometric research on human life history strategy (LHS), provides a constructive critique of the extant literature, and describes strategies for improving construct validity. To place the psychometric study of human LHS on more solid ground, our review indicates that researchers should (a) use approaches to psychometric modeling that are consistent with their philosophies of measurement, (b) confirm the dimensionality of life history indicators, and (c) establish measurement invariance for at least a subset of indicators. Because we see confirming the dimensionality of life history indicators as the next step toward placing the psychometrics of human LHS on more solid ground, we use nationally representative data and structural equation modeling to test the structure of middle adult life history indicators. We found statistically independent mating competition and Super-K dimensions and the effects of parental harshness and childhood unpredictability on Super-K were consistent with past research. However, childhood socioeconomic status had a moderate positive effect on mating competition and no effect on Super-K, while unpredictability did not predict mating competition. We conclude that human LHS is more complex than previously suggested-there does not seem to be a single dimension of human LHS among Western adults and the effects of environmental components seem to vary between mating competition and Super-K.

On the Psychometric Study of Human Life History Strategies

Directory of Open Access Journals (Sweden)

George B. Richardson

2017-02-01

Full Text Available This article attends to recent discussions of validity in psychometric research on human life history strategy (LHS, provides a constructive critique of the extant literature, and describes strategies for improving construct validity. To place the psychometric study of human LHS on more solid ground, our review indicates that researchers should (a use approaches to psychometric modeling that are consistent with their philosophies of measurement, (b confirm the dimensionality of life history indicators, and (c establish measurement invariance for at least a subset of indicators. Because we see confirming the dimensionality of life history indicators as the next step toward placing the psychometrics of human LHS on more solid ground, we use nationally representative data and structural equation modeling to test the structure of middle adult life history indicators. We found statistically independent mating competition and Super-K dimensions and the effects of parental harshness and childhood unpredictability on Super-K were consistent with past research. However, childhood socioeconomic status had a moderate positive effect on mating competition and no effect on Super-K, while unpredictability did not predict mating competition. We conclude that human LHS is more complex than previously suggested—there does not seem to be a single dimension of human LHS among Western adults and the effects of environmental components seem to vary between mating competition and Super-K.

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

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

2013-01-01

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

Demographic modelling reveals a history of divergence with gene flow for a glacially tied stonefly in a changing post-Pleistocene landscape

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Hotaling, Scott; Muhlfeld, Clint C.; Giersch, J. Joseph; Ali, Omar; Jordan, Steve; Miller, Michael R.; Luikart, Gordon; Weisrock, David W.

2018-01-01

AimClimate warming is causing extensive loss of glaciers in mountainous regions, yet our understanding of how glacial recession influences evolutionary processes and genetic diversity is limited. Linking genetic structure with the influences shaping it can improve understanding of how species respond to environmental change. Here, we used genome-scale data and demographic modelling to resolve the evolutionary history of Lednia tumana, a rare, aquatic insect endemic to alpine streams. We also employed a range of widely used data filtering approaches to quantify how they influenced population structure results.LocationAlpine streams in the Rocky Mountains of Glacier National Park, Montana, USA.TaxonLednia tumana, a stonefly (Order Plecoptera) in the family Nemouridae.MethodsWe generated single nucleotide polymorphism data through restriction-site associated DNA sequencing to assess contemporary patterns of genetic structure for 11 L. tumana populations. Using identified clusters, we assessed demographic history through model selection and parameter estimation in a coalescent framework. During population structure analyses, we filtered our data to assess the influence of singletons, missing data and total number of markers on results.ResultsContemporary patterns of population structure indicate that L. tumana exhibits a pattern of isolation-by-distance among populations within three genetic clusters that align with geography. Mean pairwise genetic differentiation (FST) among populations was 0.033. Coalescent-based demographic modelling supported divergence with gene flow among genetic clusters since the end of the Pleistocene (~13-17 kya), likely reflecting the south-to-north recession of ice sheets that accumulated during the Wisconsin glaciation.Main conclusionsWe identified a link between glacial retreat, evolutionary history and patterns of genetic diversity for a range-restricted stonefly imperiled by climate change. This finding included a history of

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

Science.gov (United States)

Bourcier De Carbon, P

1998-01-01

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

American Military Veteran Entrepreneurs: A Comprehensive Profile of Demographic, Service History, and Psychosocial Characteristics.

Science.gov (United States)

Heinz, Adrienne J; Freeman, Michael A; Harpaz-Rotem, Ilan; Pietrzak, Robert H

2017-01-01

American military veterans are nearly twice as likely to be self-employed compared to non-veterans, and are majority owners in nine percent of all businesses nationwide. Despite their contribution to the broader economy and the potential for training programs to cultivate and foster successful self-employment and veteran-lead entrepreneurial ventures, research on veteran entrepreneurs remains limited. In order to gain a better understanding of the potential strengths and vulnerabilities of veteran entrepreneurs, the current study utilized data from a large, nationally representative sample to profile self-employed veterans (n=230) and compare them to veterans who work as employees (n=1,055) with respect to demographic, military service history, and psychosocial characteristics. Results indicated that self-employed veterans were older and more educated and more likely to utilize VA healthcare. Self-employed veterans were more likely to serve in Vietnam and to serve in the military for fewer years. No differences were noted in perceived military experience, level of combat exposure, or military branch served as a function of self-employment. Although reporting more lifetime traumas, self-employed veterans did not experience higher rates of current or lifetime psychopathology or lower perceived quality of life. Potential protective resilience-promoting factors may be associated with the higher levels of openness, extraversion, optimism, achievement-orientation (purpose in life), and greater need for autonomy and professional development observed among self-employed veterans. Moreover, self-employed veterans demonstrated higher levels of gratitude, community integration, and altruistic service to others. Findings have potential to inform human resources management strategies and vocational training and reintegration initiatives for veterans.

American Military Veteran Entrepreneurs: A Comprehensive Profile of Demographic, Service History, and Psychosocial Characteristics

Science.gov (United States)

Heinz, Adrienne J.; Freeman, Michael A.; Harpaz-Rotem, Ilan; Pietrzak, Robert H.

2017-01-01

American military veterans are nearly twice as likely to be self-employed compared to non-veterans, and are majority owners in nine percent of all businesses nationwide. Despite their contribution to the broader economy and the potential for training programs to cultivate and foster successful self-employment and veteran-lead entrepreneurial ventures, research on veteran entrepreneurs remains limited. In order to gain a better understanding of the potential strengths and vulnerabilities of veteran entrepreneurs, the current study utilized data from a large, nationally representative sample to profile self-employed veterans (n=230) and compare them to veterans who work as employees (n=1,055) with respect to demographic, military service history, and psychosocial characteristics. Results indicated that self-employed veterans were older and more educated and more likely to utilize VA healthcare. Self-employed veterans were more likely to serve in Vietnam and to serve in the military for fewer years. No differences were noted in perceived military experience, level of combat exposure, or military branch served as a function of self-employment. Although reporting more lifetime traumas, self-employed veterans did not experience higher rates of current or lifetime psychopathology or lower perceived quality of life. Potential protective resilience-promoting factors may be associated with the higher levels of openness, extraversion, optimism, achievement-orientation (purpose in life), and greater need for autonomy and professional development observed among self-employed veterans. Moreover, self-employed veterans demonstrated higher levels of gratitude, community integration, and altruistic service to others. Findings have potential to inform human resources management strategies and vocational training and reintegration initiatives for veterans. PMID:29290645

Adaptable history biases in human perceptual decisions.

Science.gov (United States)

Abrahamyan, Arman; Silva, Laura Luz; Dakin, Steven C; Carandini, Matteo; Gardner, Justin L

2016-06-21

When making choices under conditions of perceptual uncertainty, past experience can play a vital role. However, it can also lead to biases that worsen decisions. Consistent with previous observations, we found that human choices are influenced by the success or failure of past choices even in a standard two-alternative detection task, where choice history is irrelevant. The typical bias was one that made the subject switch choices after a failure. These choice history biases led to poorer performance and were similar for observers in different countries. They were well captured by a simple logistic regression model that had been previously applied to describe psychophysical performance in mice. Such irrational biases seem at odds with the principles of reinforcement learning, which would predict exquisite adaptability to choice history. We therefore asked whether subjects could adapt their irrational biases following changes in trial order statistics. Adaptability was strong in the direction that confirmed a subject's default biases, but weaker in the opposite direction, so that existing biases could not be eradicated. We conclude that humans can adapt choice history biases, but cannot easily overcome existing biases even if irrational in the current context: adaptation is more sensitive to confirmatory than contradictory statistics.

Climate change and human colonization triggered habitat loss and fragmentation in Madagascar.

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Salmona, Jordi; Heller, Rasmus; Quéméré, Erwan; Chikhi, Lounès

2017-10-01

The relative effect of past climate fluctuations and anthropogenic activities on current biome distribution is subject to increasing attention, notably in biodiversity hot spots. In Madagascar, where humans arrived in the last ~4 to 5,000 years, the exact causes of the demise of large vertebrates that cohabited with humans are yet unclear. The prevailing narrative holds that Madagascar was covered with forest before human arrival and that the expansion of grasslands was the result of human-driven deforestation. However, recent studies have shown that vegetation and fauna structure substantially fluctuated during the Holocene. Here, we study the Holocene history of habitat fragmentation in the north of Madagascar using a population genetics approach. To do so, we infer the demographic history of two northern Madagascar neighbouring, congeneric and critically endangered forest dwelling lemur species-Propithecus tattersalli and Propithecus perrieri-using population genetic analyses. Our results highlight the necessity to consider population structure and changes in connectivity in demographic history inferences. We show that both species underwent demographic fluctuations which most likely occurred after the mid-Holocene transition. While mid-Holocene climate change probably triggered major demographic changes in the two lemur species range and connectivity, human settlements that expanded over the last four millennia in northern Madagascar likely played a role in the loss and fragmentation of the forest cover. © 2017 John Wiley & Sons Ltd.

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

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Ilaria A M Marino

Full Text Available 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.

Contesting 'Patriotic History': Zimbabwe's liberation war history and ...

African Journals Online (AJOL)

Remarkably, the article observes that the exclusively women authored anthology on liberation war history offers an inventory of a gender based trajectory of memory, thus ... On the other hand, the sidelined demographic categories contest narrow 'patriotic history' by engineering counter discursive historical accounts.

Primates and the Evolution of Long-Slow Life Histories

Science.gov (United States)

Jones, James Holland

2011-01-01

Summary Primates are characterized by relatively late ages at first reproduction, long lives and low fertility. Together, these traits define a life-history of reduced reproductive effort. Understanding the optimal allocation of reproductive effort, and specifically reduced reproductive effort, has been one of the key problems motivating the development of life history theory. Because of their unusual constellation of life-history traits, primates play an important role in the continued development of life history theory. In this review, I present the evidence for the reduced reproductive effort life histories of primates and discuss the ways that such life-history tactics are understood in contemporary theory. Such tactics are particularly consistent with the predictions of stochastic demographic models, suggesting a key role for environmental variability in the evolution of primate life histories. The tendency for primates to specialize in high-quality, high-variability food items may make them particularly susceptible to environmental variability and explain their low reproductive-effort tactics. I discuss recent applications of life history theory to human evolution and emphasize the continuity between models used to explain peculiarities of human reproduction and senescence with the long, slow life histories of primates more generally. PMID:21959161

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

Science.gov (United States)

Mitsui, Yuki; Setoguchi, Hiroaki

2012-12-28

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. 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. 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

Human evolution, life history theory, and the end of biological reproduction.

Science.gov (United States)

Last, Cadell

2014-01-01

Throughout primate history there have been three major life history transitions towards increasingly delayed sexual maturation and biological reproduction, as well as towards extended life expectancy. Monkeys reproduce later and live longer than do prosimians, apes reproduce later and live longer than do monkeys, and humans reproduce later and live longer than do apes. These life history transitions are connected to increased encephalization. During the last life history transition from apes to humans, increased encephalization co-evolved with increased dependence on cultural knowledge for energy acquisition. This led to a dramatic pressure for more energy investment in growth over current biological reproduction. Since the industrial revolution socioeconomic development has led to even more energy being devoted to growth over current biological reproduction. I propose that this is the beginning of an ongoing fourth major primate life history transition towards completely delayed biological reproduction and an extension of the evolved human life expectancy. I argue that the only fundamental difference between this primate life history transition and previous life history transitions is that this transition is being driven solely by cultural evolution, which may suggest some deeper evolutionary transition away from biological evolution is already in the process of occurring.

Demographic development of ukrainian rural area: lessons of history, modern socio-economic threats

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D.P. Melnychuk

2016-06-01

Full Text Available The article is devoted to urgent problems of demographic development of rural areas, their impact on socioeconomic processes at all levels of the national economic system. The content of demographic and economic antonyms of «demographic development» and «demographic catastrophe» has been characterized. The article analyzes the historical background of demographic change in rural areas, their socio-economic consequences. It’s reasonably concluded that the economic development of Ukraine requires urgent settlement of the negative socio-demographic trends that are characteristic for a Ukrainian village. Nowadays, these trends are of a destructive nature. They lead to a protracted crisis of agricultural production which is very difficult to overcome solely with the tools of technical and technological modernization. This will complicate the food security of the state for many years; lower the level and quality of life of the population, lead to greater territorial disparities and degradation of rural areas and the marginalization of residents of Ukrainian villages.

Evolution, human-microbe interactions, and life history plasticity.

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Rook, Graham; Bäckhed, Fredrik; Levin, Bruce R; McFall-Ngai, Margaret J; McLean, Angela R

2017-07-29

A bacterium was once a component of the ancestor of all eukaryotic cells, and much of the human genome originated in microorganisms. Today, all vertebrates harbour large communities of microorganisms (microbiota), particularly in the gut, and at least 20% of the small molecules in human blood are products of the microbiota. Changing human lifestyles and medical practices are disturbing the content and diversity of the microbiota, while simultaneously reducing our exposures to the so-called old infections and to organisms from the natural environment with which human beings co-evolved. Meanwhile, population growth is increasing the exposure of human beings to novel pathogens, particularly the crowd infections that were not part of our evolutionary history. Thus some microbes have co-evolved with human beings and play crucial roles in our physiology and metabolism, whereas others are entirely intrusive. Human metabolism is therefore a tug-of-war between managing beneficial microbes, excluding detrimental ones, and channelling as much energy as is available into other essential functions (eg, growth, maintenance, reproduction). This tug-of-war shapes the passage of each individual through life history decision nodes (eg, how fast to grow, when to mature, and how long to live). Copyright © 2017 Elsevier Ltd. All rights reserved.

["Human races": history of a dangerous illusion].

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Louryan, S

2014-01-01

The multiplication of offences prompted by racism and the increase of complaints for racism leads us to consider the illusory concept of "human races". This idea crossed the history, and was reinforced by the discovery of remote tribes and human fossils, and by the development of sociobiology and quantitative psychology. Deprived of scientific base, the theory of the "races" must bow before the notions of genetic variation and unicity of mankind.

Human Rights and History Education: An Australian Study

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Burridge Nina; Buchanan, John; Chodkiewicz, Andrew

2014-01-01

The place of education for and about human rights within the school curriculum remains contested and this paper reports on the first national cross-sectoral investigation of its place in Australian curricula and more specifically in national and state History curriculum documents. Opportunities for the inclusion of human rights based studies were…

Mapping Common Ground: Ecocriticism, Environmental History, and the Environmental Humanities

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Bergthaller, Hannes

2014-11-01

Full Text Available The emergence of the environmental humanities presents a unique opportunity for scholarship to tackle the human dimensions of the environmental crisis. It might finally allow such work to attain the critical mass it needs to break out of customary disciplinary confines and reach a wider public, at a time when natural scientists have begun to acknowledge that an understanding of the environmental crisis must include insights from the humanities and social sciences. In order to realize this potential, scholars in the environmental humanities need to map the common ground on which close interdisciplinary cooperation will be possible. This essay takes up this task with regard to two fields that have embraced the environmental humanities with particular fervour, namely ecocriticism and environmental history. After outlining an ideal of slow scholarship which cultivates thinking across different spatiotemporal scales and seeks to sustain meaningful public debate, the essay argues that both ecocriticism and environmental history are concerned with practices of environing: each studies the material and symbolic transformations by which “the environment” is configured as a space for human action. Three areas of research are singled out as offering promising models for cooperation between ecocriticism and environmental history: eco-historicism, environmental justice, and new materialism. Bringing the fruits of such efforts to a wider audience will require environmental humanities scholars to experiment with new ways of organizing and disseminating knowledge.

Urbanization shapes the demographic history of a native rodent (the white-footed mouse, Peromyscus leucopus) in New York City.

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Harris, Stephen E; Xue, Alexander T; Alvarado-Serrano, Diego; Boehm, Joel T; Joseph, Tyler; Hickerson, Michael J; Munshi-South, Jason

2016-04-01

How urbanization shapes population genomic diversity and evolution of urban wildlife is largely unexplored. We investigated the impact of urbanization on white-footed mice,Peromyscus leucopus,in the New York City (NYC) metropolitan area using coalescent-based simulations to infer demographic history from the site-frequency spectrum. We assigned individuals to evolutionary clusters and then inferred recent divergence times, population size changes and migration using genome-wide single nucleotide polymorphisms genotyped in 23 populations sampled along an urban-to-rural gradient. Both prehistoric climatic events and recent urbanization impacted these populations. Our modelling indicates that post-glacial sea-level rise led to isolation of mainland and Long Island populations. These models also indicate that several urban parks represent recently isolated P. leucopus populations, and the estimated divergence times for these populations are consistent with the history of urbanization in NYC. © 2016 The Author(s).

Teaching history of medicine in the perspective of "medical humanities".

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von Engelhardt, D

1999-03-01

The current interest in philosophical questions and ethical aspects of medicine turns attention towards the past and obtains suggestions and perspectives from previous descriptions and interpretations of sickness, therapy, and the relation between the patient and physician. Culture as therapy and therapy as culture are fundamental challenges for the present; physician, patient, and society, i.e., humans and humane medicine, need this dialogue, which should also be constitutive for teaching history of medicine. Through the separation of the natural sciences and the humanities, modern progress of medicine has produced many benefits but has, at the same time, raised many problems. Negative consequences of this development exist not only for the patient, but also for his personal environment and for the physician. In the course of modern history, there have been several reactions aimed at overcoming these one-sided tendencies: in the Renaissance, in the epoch of Romanticism and Idealism, and at the beginning and the end of the 19th century. This article outlines, with historical examples and contemporary reflections, the concept of teaching history of medicine in the perspective of "medical humanities".

The role of human demographic history in determining the distribution and frequency of transferase-deficient galactosaemia mutations.

LENUS (Irish Health Repository)

Flanagan, J M

2010-02-01

Classical or transferase-deficient galactosaemia is an inherited metabolic disorder caused by mutation in the human Galactose-1-phosphate uridyl transferase (GALT) gene. Of some 170 causative mutations reported, fewer than 10% are observed in more than one geographic region or ethnic group. To better understand the population history of the common GALT mutations, we have established a haplotyping system for the GALT locus incorporating eight single nucleotide polymorphisms and three short tandem repeat markers. We analysed haplotypes associated with the three most frequent GALT gene mutations, Q188R, K285N and Duarte-2 (D2), and estimated their age. Haplotype diversity, in conjunction with measures of genetic diversity and of linkage disequilibrium, indicated that Q188R and K285N are European mutations. The Q188R mutation arose in central Europe within the last 20 000 years, with its observed east-west cline of increasing relative allele frequency possibly being due to population expansion during the re-colonization of Europe by Homo sapiens in the Mesolithic age. K285N was found to be a younger mutation that originated in Eastern Europe and is probably more geographically restricted as it arose after all major European population expansions. The D2 variant was found to be an ancient mutation that originated before the expansion of Homo sapiens out of Africa.

Socio-Demographic Determinants of Eclampsia in Calabar; A Ten ...

African Journals Online (AJOL)

A ten-year review of the socio-demographic determinants of eclampsia was ... had past histories of eclampsia, while in 7 (18.4%) cases history of change of ... no formal education and 34.25% were subsistence farmers living in the suburbs of ...

Effects of geological changes and climatic fluctuations on the demographic histories and low genetic diversity of Squaliobarbus curriculus in Yellow River.

Science.gov (United States)

Zhou, Wei; Song, Na; Wang, Jun; Gao, Tianxiang

2016-09-15

The 104 samples of Squaliobarbus curriculus were collected from four localities in Yellow River and one region in Yangtze River. Analyses of the first hypervariable region of mitochondrial DNA control region of 555bp revealed only 15 polymorphism sites and defined 19 haplotypes. Low-to-moderate levels of haplotype diversity and low nucleotide diversity were observed in Yellow River populations (h=0.2529-0.7510, π=0.0712%-0.2197%). In contrast, Poyang Lake population showed high haplotype diversity and lower-middle nucleotide diversity (h=0.9636, π=0.5317%). Low genetic differentiation was estimated among Yellow River populations and significant level of genetic structure was detected between two rivers. Population genetic structure between two rivers was believed to be connected with geographical barriers and paleoclimatic events. The demographic history of S. curriculus in Yellow River examined by neutrality tests, mismatch distribution analysis, and Bayesian skyline analysis suggested a sudden and spatial population expansion dating to the Holocene. Climatic warming and changes of Yellow River course may have important effects on demographic facet of S. curriculus history. The same signal was also obtained on Poyang Lake population in late Pleistocene during the last interglacial period. During the period, the pronounced climatic change and the water system variation of PYL may have an important influence on the population. Copyright © 2016 Elsevier B.V. All rights reserved.

Learning about human population history from ancient and modern genomes.

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Stoneking, Mark; Krause, Johannes

2011-08-18

Genome-wide data, both from SNP arrays and from complete genome sequencing, are becoming increasingly abundant and are now even available from extinct hominins. These data are providing new insights into population history; in particular, when combined with model-based analytical approaches, genome-wide data allow direct testing of hypotheses about population history. For example, genome-wide data from both contemporary populations and extinct hominins strongly support a single dispersal of modern humans from Africa, followed by two archaic admixture events: one with Neanderthals somewhere outside Africa and a second with Denisovans that (so far) has only been detected in New Guinea. These new developments promise to reveal new stories about human population history, without having to resort to storytelling.

Teaching Recent History in Countries that Have Experienced Human Rights Violations: Case Studies from Chile

Science.gov (United States)

Toledo, Maria Isabel; Magendzo, Abraham; Gazmuri, Renato

2011-01-01

Incorporating recent history into the educational curricula of countries that have experienced human rights violations combines the complexities of teaching history, teaching recent history, and human rights education. Recent history makes a historical analysis of social reality and a historiographical analysis of the immediate. It is located…

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

Science.gov (United States)

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

2011-01-01

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

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

Science.gov (United States)

Barnett, Ross; Yamaguchi, Nobuyuki; Shapiro, Beth; Ho, Simon Y W; Barnes, Ian; Sabin, Richard; Werdelin, Lars; Cuisin, Jacques; Larson, Greger

2014-04-02

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. 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. 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.

SHARI’A, INDIGENOUS WISDOM AND HUMAN RIGHTS: A Brief Review of Human Rights Enforcement in the Context of Indonesian History

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JM. Muslimin

2015-12-01

Full Text Available This article deals with the analysis of how human rights discourses have been articulated in the landscape of Indonesia’s history. The paper argues that the idea of Shari’aization can undermine the search for the common ground in building the discourses of human rights. The history of Indonesia can be classified into three eras: pre-colonial, post-colonial and reform era. Along the history, the spirit of human rights enforcement grows from, and interacts with, Islam and local culture. The language and expression take various forms in accordance with socio-cultural contexts and challenges. However, the essence of the enforcement is rooted in the universal values: freedom from oppression, fear, discrimination and gender inequality. In the future, smart dialogue, sharp debate and sincere discussion between ‘local’ symbolic expression and universal standardization are still needed. In addition, the gap can be narrowed also by responding actual violation of human right as it is indicated by Indonesian history: history of social consensus.

Genetic Pattern and Demographic History of Salminus brasiliensis: Population Expansion in the Pantanal Region during the Pleistocene

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Lívia A. de Carvalho Mondin

2018-01-01

Full Text Available Pleistocene climate changes were major historical events that impacted South American biodiversity. Although the effects of such changes are well-documented for several biomes, it is poorly known how these climate shifts affected the biodiversity of the Pantanal floodplain. Fish are one of the most diverse groups in the Pantanal floodplains and can be taken as a suitable biological model for reconstructing paleoenvironmental scenarios. To identify the effects of Pleistocene climate changes on Pantanal’s ichthyofauna, we used genetic data from multiple populations of a top-predator long-distance migratory fish, Salminus brasiliensis. We specifically investigated whether Pleistocene climate changes affected the demography of this species. If this was the case, we expected to find changes in population size over time. Thus, we assessed the genetic diversity of S. brasiliensis to trace the demographic history of nine populations from the Upper Paraguay basin, which includes the Pantanal floodplain, that form a single genetic group, employing approximate Bayesian computation (ABC to test five scenarios: constant population, old expansion, old decline, old bottleneck following by recent expansion, and old expansion following by recent decline. Based on two mitochondrial DNA markers, our inferences from ABC analysis, the results of Bayesian skyline plot, the implications of star-like networks, and the patterns of genetic diversity (high haplotype diversity and low-to-moderate nucleotide diversity indicated a sudden population expansion. ABC allowed us to make strong quantitative inferences about the demographic history of S. brasiliensis. We estimated a small ancestral population size that underwent a drastic fivefold expansion, probably associated with the colonization of newly formed habitats. The estimated time of this expansion was consistent with a humid and warm phase as inferred by speleothem growth phases and travertine records during

Demographic changes and marker properties affect detection of human population differentiation

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Sanichwankul Kittipong

2007-05-01

Full Text Available Abstract Background Differentiating genetically between populations is valuable for admixture and population stratification detection and in understanding population history. This is easy to achieve for major continental populations, but not for closely related populations. It has been claimed that a large marker panel is necessary to reliably distinguish populations within a continent. We investigated whether empirical genetic differentiation could be accomplished efficiently among three Asian populations (Hmong, Thai, and Chinese using a small set of highly variable markers (15 tetranucleotide and 17 dinucleotide repeats. Results Hmong could be differentiated from Thai and Chinese based on multi-locus genotypes, but Thai and Chinese were indistinguishable from each other. We found significant evidence for a recent population bottleneck followed by expansion in the Hmong that was not present in the Thai or Chinese. Tetranucleotide repeats were less useful than dinucleotide repeat markers in distinguishing between major continental populations (Asian, European, and African while both successfully distinguished Hmong from Thai and Chinese. Conclusion Demographic history contributes significantly to robust detection of intracontinental population structure. Populations having experienced a rapid size reduction may be reliably distinguished as a result of a genetic drift -driven redistribution of population allele frequencies. Tetranucleotide markers, which differ from dinucleotide markers in mutation mechanism and rate, are similar in information content to dinucleotide markers in this situation. These factors should be considered when identifying populations suitable for gene mapping studies and when interpreting interpopulation relationships based on microsatellite markers.

Laboratory Demographics Lookup Tool

Data.gov (United States)

U.S. Department of Health & Human Services — This website provides demographic information about laboratories, including CLIA number, facility name and address, where the laboratory testing is performed, the...

New approaches to human mobility: using mobile phones for demographic research.

Science.gov (United States)

Palmer, John R B; Espenshade, Thomas J; Bartumeus, Frederic; Chung, Chang Y; Ozgencil, Necati Ercan; Li, Kathleen

2013-06-01

This article explores new methods for gathering and analyzing spatially rich demographic data using mobile phones. It describes a pilot study (the Human Mobility Project) in which volunteers around the world were successfully recruited to share GPS and cellular tower information on their trajectories and respond to dynamic, location-based surveys using an open-source Android application. The pilot study illustrates the great potential of mobile phone methodology for moving spatial measures beyond residential census units and investigating a range of important social phenomena, including the heterogeneity of activity spaces, the dynamic nature of spatial segregation, and the contextual dependence of subjective well-being.

Influence Of Demographic Factors And History Of Malaria With The Incidence Malaria In MORU PHC

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Sudirman Manumpa

2017-01-01

Full Text Available Malaria morbidity in Moru health center, with parameter Annual Parasite Incident (API, amounted to 16.9% in 2014. This figure was still high when compared to the target of eliminating malaria in Indonesia about <1% in 2030. Incidence of malaria is more common in children aged 5 months - <12 years. This high rates of malaria leads to poverty, low level of learning achievement of children and in pregnant women causing low birth weight in babies and death. The purpose of this study was to analyze the factors that influence the incidence of tertian and Tropikana malaria or combined Tropikana and tertian (mix in Moru PHC in sub-district Alor Southwestern, Alor Regency.This study used a cross-sectional design, the population of study were all patients undergoing peripheral blood examination in Moru PHC’s laboratory from June to October 2015. The number of samples in this study was 173 respondents. The sampling technique was Simple Random Sampling. Instruments of data collection were a questionnaire and observation sheet.Results of the study by Chi-Square test showed that the factors influencing the incidence of malaria were socioeconomic status (sig 0,000, education level (sig 0.001. By using multivariate analysis with logistic regression test, results were obtained the age of 5 months - <12 value (sig 0.025 and socioeconomic status (sig 0,000 influencing the incidence of malaria.Variables that affect the incidence of malaria were demographic factors such as age, education level, socioeconomic status. It is advisable to harness swamp thus improving the economic status of society and build permanent house. Keywords: incidence malaria, demographic factors, history of malaria

Tropical rainforests that persisted: inferences from the Quaternary demographic history of eight tree species in the Guiana shield.

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Barthe, Stéphanie; Binelli, Giorgio; Hérault, Bruno; Scotti-Saintagne, Caroline; Sabatier, Daniel; Scotti, Ivan

2017-02-01

How Quaternary climatic and geological disturbances influenced the composition of Neotropical forests is hotly debated. Rainfall and temperature changes during and/or immediately after the last glacial maximum (LGM) are thought to have strongly affected the geographical distribution and local abundance of tree species. The paucity of the fossil records in Neotropical forests prevents a direct reconstruction of such processes. To describe community-level historical trends in forest composition, we turned therefore to inferential methods based on the reconstruction of past demographic changes. In particular, we modelled the history of rainforests in the eastern Guiana Shield over a timescale of several thousand generations, through the application of approximate Bayesian computation and maximum-likelihood methods to diversity data at nuclear and chloroplast loci in eight species or subspecies of rainforest trees. Depending on the species and on the method applied, we detected population contraction, expansion or stability, with a general trend in favour of stability or expansion, with changes presumably having occurred during or after the LGM. These findings suggest that Guiana Shield rainforests have globally persisted, while expanding, through the Quaternary, but that different species have experienced different demographic events, with a trend towards the increase in frequency of light-demanding, disturbance-associated species. © 2016 John Wiley & Sons Ltd.

Demographic History and Reproductive Output Correlates with Intraspecific Genetic Variation in Seven Species of Indo-Pacific Mangrove Crabs.

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Fratini, Sara; Ragionieri, Lapo; Cannicci, Stefano

2016-01-01

The spatial distribution and the amount of intraspecific genetic variation of marine organisms are strongly influenced by many biotic and abiotic factors. Comparing biological and genetic data characterizing species living in the same habitat can help to elucidate the processes driving these variation patterns. Here, we present a comparative multispecies population genetic study on seven mangrove crabs co-occurring in the West Indian Ocean characterized by planktotrophic larvae with similar pelagic larval duration. Our main aim was to investigate whether a suite of biological, behavioural and ecological traits could affect genetic diversities of the study species in combination with historical demographic parameters. As possible current explanatory factors, we used the intertidal micro-habitat colonised by adult populations, various parameters of individual and population fecundity, and the timing of larval release. As the genetic marker, we used partial sequences of cytochrome oxidase subunit I gene. Genetic and ecological data were collected by the authors and/or gathered from primary literature. Permutational multiple regression models and ANOVA tests showed that species density and their reproductive output in combination with historical demographic parameters could explain the intraspecific genetic variation indexes across the seven species. In particular, species producing consistently less eggs per spawning event showed higher values of haplotype diversity. Moreover, Tajima's D parameters well explained the recorded values for haplotype diversity and average γst. We concluded that current intraspecific gene diversities in crabs inhabiting mangrove forests were affected by population fecundity as well as past demographic history. The results were also discussed in terms of management and conservation of fauna in the Western Indian Ocean mangroves.

Demographic History and Reproductive Output Correlates with Intraspecific Genetic Variation in Seven Species of Indo-Pacific Mangrove Crabs.

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Sara Fratini

Full Text Available The spatial distribution and the amount of intraspecific genetic variation of marine organisms are strongly influenced by many biotic and abiotic factors. Comparing biological and genetic data characterizing species living in the same habitat can help to elucidate the processes driving these variation patterns. Here, we present a comparative multispecies population genetic study on seven mangrove crabs co-occurring in the West Indian Ocean characterized by planktotrophic larvae with similar pelagic larval duration. Our main aim was to investigate whether a suite of biological, behavioural and ecological traits could affect genetic diversities of the study species in combination with historical demographic parameters. As possible current explanatory factors, we used the intertidal micro-habitat colonised by adult populations, various parameters of individual and population fecundity, and the timing of larval release. As the genetic marker, we used partial sequences of cytochrome oxidase subunit I gene. Genetic and ecological data were collected by the authors and/or gathered from primary literature. Permutational multiple regression models and ANOVA tests showed that species density and their reproductive output in combination with historical demographic parameters could explain the intraspecific genetic variation indexes across the seven species. In particular, species producing consistently less eggs per spawning event showed higher values of haplotype diversity. Moreover, Tajima's D parameters well explained the recorded values for haplotype diversity and average γst. We concluded that current intraspecific gene diversities in crabs inhabiting mangrove forests were affected by population fecundity as well as past demographic history. The results were also discussed in terms of management and conservation of fauna in the Western Indian Ocean mangroves.

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

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

2013-01-01

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

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

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Eunice M. Matte

2013-01-01

Full Text Available 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.

From farmers to merchants, conversions and diaspora: human capital and Jewish history

OpenAIRE

Botticini, Maristella; Eckstein, Zvi

2007-01-01

From the end of the second century CE, Judaism enforced a religious norm requiring fathers to educate their sons. We present evidence supporting our thesis that this change had a major influence on Jewish economic and demographic history. First, the high individual and community cost of educating children in subsistence farming economies (2nd to 7th centuries) prompted voluntary conversions of Jews that account for a share of the reduction from 4.5 to 1.2 million. Second, the Jewish farmer...

Demographic histories, isolation and social factors as determinants of the genetic structure of Alpine linguistic groups.

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Valentina Coia

Full Text Available 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

Demographic histories, isolation and social factors as determinants of the genetic structure of Alpine linguistic groups.

Science.gov (United States)

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

2013-01-01

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

A Comparative Framework for Studying the Histories of the Humanities and Science.

Science.gov (United States)

Bod, Rens

2015-06-01

While the humanities and the sciences have a closely connected history, there are no general histories that bring the two fields together on an equal footing. This paper argues that there is a level at which some humanistic and scientific disciplines can be brought under a common denominator and compared. This is at the level of underlying methods, especially at the level of formalisms and rule systems used by different disciplines. The essay formally compares linguistics and computer science by noting that the same grammar formalism was used in the 1950s for describing both human and. programming languages. Additionally, it examines the influence of philology on molecular biology, and vice versa, by recognizing that the tree-formalism and rule system used for text reconstruction was also employed in DNA genetics. It also shows that rule systems for source criticism in history are used in forensic science, evidence-based medicine, and jurisprudence. This paper thus opens up a new comparative approach within which the histories of the humanities and the sciences can be examined on a common level.

Genomic differentiation and demographic histories of Atlantic and Indo-Pacific yellowfin tuna (Thunnus albacares) populations.

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Barth, J M I; Damerau, M; Matschiner, M; Jentoft, S; Hanel, R

2017-04-13

Recent developments in the field of genomics have provided new and powerful insights into population structure and dynamics that are essential for the conservation of biological diversity. As a commercially highly valuable species, the yellowfin tuna (Thunnus albacares) is intensely exploited throughout its distribution in tropical oceans around the world, and is currently classified as near threatened. However, conservation efforts for this species have so far been hampered by limited knowledge of its population structure, due to incongruent results of previous investigations. Here, we use whole-genome sequencing in concert with a draft genome assembly to decipher the global population structure of the yellowfin tuna, and to investigate its demographic history. We detect significant differentiation of Atlantic and Indo-Pacific yellowfin tuna populations as well as the possibility of a third diverged yellowfin tuna group in the Arabian Sea. We further observe evidence for past population expansion as well as asymmetric gene flow from the Indo-Pacific to the Atlantic. © The Author(s) 2017. Published by Oxford University Press on behalf of the Society for Molecular Biology and Evolution.

A brief history of human blood groups.

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Farhud, Dariush D; Zarif Yeganeh, Marjan

2013-01-01

The evolution of human blood groups, without doubt, has a history as old as man himself. There are at least three hypotheses about the emergence and mutation of human blood groups. Global distribution pattern of blood groups depends on various environmental factors, such as disease, climate, altitude, humidity etc. In this survey, the collection of main blood groups ABO and Rh, along with some minor groups, are presented. Several investigations of blood groups from Iran, particularly a large sampling on 291857 individuals from Iran, including the main blood groups ABO and Rh, as well as minor blood groups such as Duffy, Lutheran, Kell, KP, Kidd, and Xg, have been reviewed.

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

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

2012-08-23

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.

[When history meets molecular medicine: molecular history of human tuberculosis].

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Ottini, Laura; Falchetti, Mario

2010-01-01

Tuberculosis represents one of the humankind's most socially devastating diseases. Despite a long history of medical research and the development of effective therapies, this disease remains a global health danger even in the 21st century. Tuberculosis may cause death but infected people with effective immunity may remain healthy for years, suggesting long-term host-pathogen co-existence. Because of its antiquity, a supposed association with human settlements and the tendency to leave typical lesions on skeletal and mummified remains, tuberculosis has been the object of intensive multidisciplinary studies, including paleo-pathological research. During the past 10 years molecular paleo-pathology developed as a new scientific discipline allowing the study of ancient pathogens by direct detection of their DNA. In this work, we reviewed evidences for tuberculosis in ancient human remains, current methods for identifying ancient mycobacterial DNA and explored current theories of Mycobacterium tuberculosis evolution and their implications in the global development of tuberculosis looking into the past and present at the same time.

Trauma history is associated with prior suicide attempt history in hospitalized patients with major depressive disorder.

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Brown, Lily A; Armey, Michael A; Sejourne, Corinne; Miller, Ivan W; Weinstock, Lauren M

2016-09-30

Although the relationships between PTSD, abuse history, and suicidal behaviors are well-established in military and outpatient samples, little data is available on this relationship in inpatient samples. This study examines the relationships between these variables and related demographic and clinical correlates in a sample of psychiatric inpatients with a diagnosis of major depressive disorder using electronic medical record (EMR) data. Controlling for relevant demographic and clinical variables, PTSD diagnosis and history of abuse were both significantly associated with history of suicide attempt, but in a combined model, only history of abuse remained as a significant predictor. Whereas history of abuse was associated with a history multiple suicide attempts, PTSD diagnosis was not. Both insurance status and gender acted as significant moderators of the relationship between history of abuse and history of suicide attempt, with males and those with public/no insurance having greater associations with history of suicide attempts when an abuse history was present. These data indicate the importance of documentation of PTSD, abuse history, and history of suicide attempts. The results also suggest that in the presence of an abuse history or PTSD diagnosis, additional time spent on safety and aftercare planning following hospital discharge may be indicated. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

Human Life History Strategies.

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Chua, Kristine J; Lukaszewski, Aaron W; Grant, DeMond M; Sng, Oliver

2017-01-01

Human life history (LH) strategies are theoretically regulated by developmental exposure to environmental cues that ancestrally predicted LH-relevant world states (e.g., risk of morbidity-mortality). Recent modeling work has raised the question of whether the association of childhood family factors with adult LH variation arises via (i) direct sampling of external environmental cues during development and/or (ii) calibration of LH strategies to internal somatic condition (i.e., health), which itself reflects exposure to variably favorable environments. The present research tested between these possibilities through three online surveys involving a total of over 26,000 participants. Participants completed questionnaires assessing components of self-reported environmental harshness (i.e., socioeconomic status, family neglect, and neighborhood crime), health status, and various LH-related psychological and behavioral phenotypes (e.g., mating strategies, paranoia, and anxiety), modeled as a unidimensional latent variable. Structural equation models suggested that exposure to harsh ecologies had direct effects on latent LH strategy as well as indirect effects on latent LH strategy mediated via health status. These findings suggest that human LH strategies may be calibrated to both external and internal cues and that such calibrational effects manifest in a wide range of psychological and behavioral phenotypes.

Human Life History Strategies

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Kristine J. Chua

2016-12-01

Full Text Available Human life history (LH strategies are theoretically regulated by developmental exposure to environmental cues that ancestrally predicted LH-relevant world states (e.g., risk of morbidity–mortality. Recent modeling work has raised the question of whether the association of childhood family factors with adult LH variation arises via (i direct sampling of external environmental cues during development and/or (ii calibration of LH strategies to internal somatic condition (i.e., health, which itself reflects exposure to variably favorable environments. The present research tested between these possibilities through three online surveys involving a total of over 26,000 participants. Participants completed questionnaires assessing components of self-reported environmental harshness (i.e., socioeconomic status, family neglect, and neighborhood crime, health status, and various LH-related psychological and behavioral phenotypes (e.g., mating strategies, paranoia, and anxiety, modeled as a unidimensional latent variable. Structural equation models suggested that exposure to harsh ecologies had direct effects on latent LH strategy as well as indirect effects on latent LH strategy mediated via health status. These findings suggest that human LH strategies may be calibrated to both external and internal cues and that such calibrational effects manifest in a wide range of psychological and behavioral phenotypes.

Demographic and spatio-temporal variation in human plague at a persistent focus in Tanzania

DEFF Research Database (Denmark)

Davis, S; Makundi, R H; Machang'u, R S

2006-01-01

Human plague in the Western Usambara Mountains in Tanzania has been a public health problem since the first outbreak in 1980. The wildlife reservoir is unknown and eradication measures that have proved effective elsewhere in Tanzania appear to fail in this region. We use census data from 2002...... and hospital records kept since 1986 to describe the temporal, spatial and demographic variation in human plague. A seasonal peak in cases occurs from December to February with the numbers of cases during this peak varying between 0 and 1150. Variation in incidence, calculated for each village as the mean...... number of cases per thousand inhabitants per year, indicates that human plague is concentrated around a group of three neighbouring, relatively isolated, high-altitude villages; Nywelo, Madala and Gologolo. However, there was no evidence that these villages were acting as a source of infection...

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

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Dong-Xiu Xue

Full Text Available 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.

Modeling evolutionary games in populations with demographic structure

DEFF Research Database (Denmark)

Li, Xiang-Yi; Giaimo, Stefano; Baudisch, Annette

2015-01-01

interactions, but usually omits life history and the demographic structure of the population. Here we show how an integration of both aspects can substantially alter the underlying evolutionary dynamics. We study the replicator dynamics of strategy interactions in life stage structured populations. Individuals...

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

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

2014-03-01

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

Study of human genetic diversity : inferences on population origin and history

OpenAIRE

Haber, Marc, 1980-

2013-01-01

Patterns of human genetic diversity suggest that all modern humans originated from a small population in Africa that expanded rapidly 50,000 years ago to occupy the whole world. While moving into new environments, genetic drift and natural selection affected populations differently, creating genetic structure. By understanding the genetic structure of human populations, we can reconstruct human history and understand the genetic basis of diseases. The work presented here contributes to the on...

Life-history stages of the jellyfish Aurelia aurita - towards a demographic understanding of jellyfish blooms

DEFF Research Database (Denmark)

Goldstein, Josephine

2017-01-01

Jellyfish blooms are conspicuous demographic events that have received increasing attention by the public and the scientific community over the last decades due to their negative impact on fisheries, tourism and other human industries. Several aspects of the complex life cycles of the jellyfish......, including frequent mass occurrence of A. aurita medusae in temperate Danish waters. The present novel data show for instance, that jellyfish blooms of A. aurita are strongly affected by food availability and corresponding shifts between asexually reproducing benthic polyps and sexually reproducing pelagic...... medusae, which might be highly representative for the majority of bloom-forming jellyfish species. Findings further indicate that seasonal shrinkage and subsequent disappearance of A. aurita medusae is rather driven by food limitation than by a trade-off between sexual reproduction and metabolic...

Contrasting demographic history and gene flow patterns of two mangrove species on either side of the Central American Isthmus

Science.gov (United States)

Cerón-Souza, Ivania; Gonzalez, Elena G; Schwarzbach, Andrea E; Salas-Leiva, Dayana E; Rivera-Ocasio, Elsie; Toro-Perea, Nelson; Bermingham, Eldredge; McMillan, W Owen

2015-01-01

Comparative phylogeography offers a unique opportunity to understand the interplay between past environmental events and life-history traits on diversification of unrelated but co-distributed species. Here, we examined the effects of the quaternary climate fluctuations and palaeomarine currents and present-day marine currents on the extant patterns of genetic diversity in the two most conspicuous mangrove species of the Neotropics. The black (Avicennia germinans, Avicenniaceae) and the red (Rhizophora mangle, Rhizophoraceae) mangroves have similar geographic ranges but are very distantly related and show striking differences on their life-history traits. We sampled 18 Atlantic and 26 Pacific locations for A. germinans (N = 292) and R. mangle (N = 422). We performed coalescence simulations using microsatellite diversity to test for evidence of population change associated with quaternary climate fluctuations. In addition, we examined whether patterns of genetic variation were consistent with the directions of major marine (historical and present day) currents in the region. Our demographic analysis was grounded within a phylogeographic framework provided by the sequence analysis of two chloroplasts and one flanking microsatellite region in a subsample of individuals. The two mangrove species shared similar biogeographic histories including: (1) strong genetic breaks between Atlantic and Pacific ocean basins associated with the final closure of the Central American Isthmus (CAI), (2) evidence for simultaneous population declines between the mid-Pleistocene and early Holocene, (3) asymmetric historical migration with higher gene flow from the Atlantic to the Pacific oceans following the direction of the palaeomarine current, and (4) contemporary gene flow between West Africa and South America following the major Atlantic Ocean currents. Despite the remarkable differences in life-history traits of mangrove species, which should have had a strong influence on seed

A Comparative Framework for Studying the Histories of the Humanities and Science

NARCIS (Netherlands)

Bod, R.

2015-01-01

While the humanities and the sciences have a closely connected history, there are no general histories that bring the two fields together on an equal footing. This paper argues that there is a level at which some humanistic and scientific disciplines can be brought under a common denominator and

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

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Hewitt Godfrey M

2011-06-01

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

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

Science.gov (United States)

Miraldo, Andreia; Hewitt, Godfrey M; Paulo, Octavio S; Emerson, Brent C

2011-06-17

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

Genomics and the Ark: an ecocentric perspective on human history.

Science.gov (United States)

Zwart, Hub; Penders, Bart

2011-01-01

Views of ourselves in relationship to the rest of the biosphere are changing. Theocentric and anthropocentric perspectives are giving way to more ecocentric views on the history, present, and future of humankind. Novel sciences, such as genomics, have deepened and broadened our understanding of the process of anthropogenesis, the coming into being of humans. Genomics suggests that early human history must be regarded as a complex narrative of evolving ecosystems, in which human evolution both influenced and was influenced by the evolution of companion species. During the agricultural revolution, human beings designed small-scale artificial ecosystems or evolutionary "Arks," in which networks of plants, animals, and microorganisms coevolved. Currently, our attitude towards this process seems subject to a paradoxical reversal. The boundaries of the Ark have dramatically broadened, and genomics is not only being used to increase our understanding of our ecological past, but may also help us to conserve, reconstruct, or even revivify species and ecosystems to whose degradation or (near) extinction we have contributed. This article explores the role of genomics in the elaboration of a more ecocentric view of ourselves with the help of two examples, namely the renaissance of Paleolithic diets and of Pleistocene parks. It argues that an understanding of the world in ecocentric terms requires new partnerships and mutually beneficial forms of collaboration and convergence between life sciences, social sciences, and the humanities.

[From personnel administration to human resource management : demographic risk management in hospitals].

Science.gov (United States)

Schmidt, C E; Gerbershagen, M U; Salehin, J; Weib, M; Schmidt, K; Wolff, F; Wappler, F

2011-06-01

The healthcare market is facing a serious shortage of qualified personnel in 2020. Aging of staff members is one important driver of this human resource deficit but current planning periods of 1-2 years cannot compensate the demographic effects on staff portfolio early enough. Therefore, prospective human resource planning is important to avoid loss of competence. The long range development (10 years) of human resources in the hospitals of the City of Cologne was analyzed. The basis for the analysis was a simulation model that included fluctuation of staff, retirement, maternity leave, status of employee illness, partial retirement and fresh engagements per department and profession. The model was matched with the staff requirements for each department. The results showed a capacity analysis which was used to convey strategic measures for staff recruitment and retention. The greatest risk for shortage of qualified staff was found in the fluctuation of doctors and in the aging work force. Without strategic human resource management the hospitals would face a 50% reduction of the work force within 10 years and after 2 years there would be a 25% deficit of anesthesiologists with impact on the function of operation rooms (OR) and intensive care units. Qualification and continuous training of staff members as well as process optimization are the most important spheres of activity for human resource management in order to recruit and retain qualified staff members. Prospective human resource planning for the OR and intensive care units can help to detect shortage of staff and loss of competence early enough to apply effective personnel development measures. A growing number of companies have started to plan ahead of the current demand of human resources. Hospitals should follow this example because the competition for qualified staff members is increasing rapidly.

Inferences of population structure and demographic history for Taxodium distichum, a coniferous tree in North America, based on amplicon sequencing analysis.

Science.gov (United States)

Ikezaki, Yuka; Suyama, Yoshihisa; Middleton, Beth A; Tsumura, Yoshihiko; Teshima, Kousuke; Tachida, Hidenori; Kusumi, Junko

2016-11-01

Studies of natural genetic variation can elucidate the genetic basis of phenotypic variation and the past population structure of species. Our study species, Taxodium distichum, is a unique conifer that inhabits the flood plains and swamps of North America. Morphological and ecological differences in two varieties, T. distichum var. distichum (bald cypress) and T. distichum var. imbricarium (pond cypress), are well known, but little is known about the level of genetic differentiation between the varieties and the demographic history of local populations. We analyzed nucleotide polymorphisms at 47 nuclear loci from 96 individuals collected from the Mississippi River Alluvial Valley (MRAV), and Gulf Coastal populations in Texas, Louisiana, and Florida using high-throughput DNA sequencing. Standard population genetic statistics were calculated, and demographic parameters were estimated using a composite-likelihood approach. Taxodium distichum in North America can be divided into at least three genetic groups, bald cypress in the MRAV and Texas, bald cypress in Florida, and pond cypress in Florida. The levels of genetic differentiation among the groups were low but significant. Several loci showed the signatures of positive selection, which might be responsible for local adaptation or varietal differentiation. Bald cypress was genetically differentiated into two geographical groups, and the boundary was located between the MRAV and Florida. This differentiation could be explained by population expansion from east to west. Despite the overlap of the two varieties' ranges, they were genetically differentiated in Florida. The estimated demographic parameters suggested that pond cypress split from bald cypress during the late Miocene. © 2016 Botanical Society of America.

Inference of population structure and demographic history in Taxodium distichum, a coniferous tree in North America, based on amplicon sequence analysis

Science.gov (United States)

Ikezaki, Yuka; Suyama, Yoshihisa; Middleton, Beth A.; Tsumura, Yoshihiko; Teshima, Kousuke; Tachida, Hidenori; Kusumi, Junko

2016-01-01

PREMISE OF THE STUDY: Studies of natural genetic variation can elucidate the genetic basis of phenotypic variation and the past population structure of species. Our study species, Taxodium distichum, is a unique conifer that inhabits the flood plains and swamps of North America. Morphological and ecological differences in two varieties, T. distichum var. distichum (bald cypress) and T. distichum var. imbricarium (pond cypress), are well known, but little is known about the level of genetic differentiation between the varieties and the demographic history of local populations.METHODS: We analyzed nucleotide polymorphisms at 47 nuclear loci from 96 individuals collected from the Mississippi River Alluvial Valley (MRAV), and Gulf Coastal populations in Texas, Louisiana, and Florida using high-throughput DNA sequencing. Standard population genetic statistics were calculated, and demographic parameters were estimated using a composite-likelihood approach.KEY RESULTS: Taxodium distichum in North America can be divided into at least three genetic groups, bald cypress in the MRAV and Texas, bald cypress in Florida, and pond cypress in Florida. The levels of genetic differentiation among the groups were low but significant. Several loci showed the signatures of positive selection, which might be responsible for local adaptation or varietal differentiation.CONCLUSIONS: Bald cypress was genetically differentiated into two geographical groups, and the boundary was located between the MRAV and Florida. This differentiation could be explained by population expansion from east to west. Despite the overlap of the two varieties’ ranges, they were genetically differentiated in Florida. The estimated demographic parameters suggested that pond cypress split from bald cypress during the late Miocene.

The cooperative economy of food: Implications for human life history and physiology.

Science.gov (United States)

Kramer, Karen L

2018-04-06

The human diet has undergone substantial modifications since the emergence of modern humans and varies considerably in today's traditional societies. Despite these changes and cross-cultural differences, the human diet can be characterized by several common elements. These include diverse, high quality foods, technological complexity to acquire and process food, and the establishment of home bases for storage, processing and consumption. Together these aspects of the human diet challenge any one individual to independently meet all of his or her daily caloric needs. Humans solve this challenge through food sharing, labor exchange and the division of labor. The cooperative nature of the human diet is associated with many downstream effects on our life history and physiology. This paper overviews the constellation of traits that likely led to a cooperative economy of food, and draws on ethnographic examples to illustrate its effects on human life history and physiology. Two detailed examples using body composition, time allocation and food acquisition data show how cooperation among Savanna Pumé hunter-gatherers affects activity levels, sexual dimorphism in body fat, maturational pace and age at first birth. Copyright © 2018. Published by Elsevier Inc.

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

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

2014-11-01

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

Tension in the Natural History of Human Thinking

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Moll Henrike

2016-03-01

Full Text Available Michael Tomasello has greatly expanded our knowledge of human cognition and how it differs from that of other animals. In this commentary to his recent book A Natural History of Human Thinking, I first critique some of the presuppositions and arguments of his evolutionary story about how homo sapiens’ cognition emerged. For example, I question the strategy of relying on the modern chimpanzee as a model for our last shared ancestor, and I doubt the idea that what changed first over evolutionary time was hominin behavior, which then in turn brought about changes in cognition. In the second half of the commentary I aim to show that the author oscillates between an additive and a transformative account of human shared intentionality. I argue that shared intentionality shapes cognition in its entirety and therefore precludes the possibility that humans have the same, individual intentionality (as shown in, e.g. their instrumental reasoning as other apes.

Missing Pages from the Human Story: World History According to Texas Standards

Science.gov (United States)

Noboa, Julio

2012-01-01

For more than a decade, the world history course taught in the public high schools of Texas has provided the only comprehensive overview of the story of humanity to millions of students, most of whom are of Mexican descent. The Texas Essential Knowledge and Skills curriculum standard for world history has been foundational for textbook selection,…

Population momentum across vertebrate life histories

Science.gov (United States)

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

2006-01-01

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

Assessing the evolutionary impact of amino acid mutations in the human genome

DEFF Research Database (Denmark)

Boyko, Adam R; Williamson, Scott H; Indap, Amit R

2008-01-01

Quantifying the distribution of fitness effects among newly arising mutations in the human genome is key to resolving important debates in medical and evolutionary genetics. Here, we present a method for inferring this distribution using Single Nucleotide Polymorphism (SNP) data from a population...... of demographic and selective effects to patterning amino acid variation in the human genome. We find evidence of an ancient population expansion in the sample with African ancestry and a relatively recent bottleneck in the sample with European ancestry. After accounting for these demographic effects, we find...... with non-stationary demographic history (such as that of modern humans). Application of our method to 47,576 coding SNPs found by direct resequencing of 11,404 protein coding-genes in 35 individuals (20 European Americans and 15 African Americans) allows us to assess the relative contribution...

Phylogeographic analyses of the pampas cat (Leopardus colocola; Carnivora, Felidae) reveal a complex demographic history

Science.gov (United States)

da Silva Santos, Anelisie; Trigo, Tatiane Campos; de Oliveira, Tadeu Gomes; Silveira, Leandro

2018-01-01

Abstract The pampas cat is a small felid that occurs in open habitats throughout much of South America. Previous studies have revealed intriguing patterns of morphological differentiation and genetic structure among its populations, as well as molecular evidence for hybridization with the closely related L. tigrinus. Here we report phylogeographic analyses encompassing most of its distribution (focusing particularly on Brazilian specimens, which had been poorly sampled in previous studies), using a novel dataset comprising 2,143 bp of the mitogenome, along with previously reported mtDNA sequences. Our data revealed strong population strutucture and supported a west-to-east colonization process in this species’ history. We detected two population expansion events, one older (ca. 200 thousand years ago [kya]) in western South America and another more recent (ca. 60-50 kya) in eastern areas, coinciding with the expansion of savanna environments in Brazil. Analyses including L. tigrinus individuals bearing introgressed mtDNA from L. colocola showed a complete lack of shared haplotypes between species, indicating that their hybridization was ancient. Finally, we observed a close relationship between Brazilian/Uruguayan L. colocola haplotypes and those sampled in L. tigrinus, indicating that their hybridization was likely related to the demographic expansion of L. colocola into eastern South America. PMID:29668017

Demographic model of the Neolithic transition in Central Europe

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Patrik Galeta

2009-12-01

Full Text Available Several recent lines of evidence indicate more intensive contact between LBK farmers and indigenous foragers in Central Europe (5600–5400 calBC. Strong continuity has been identified between Mesolithic and Neolithic material cultures; faunal assemblages, and isotopic analyses of diet have revealed a greater role of hunting in LBK communities; genetic analyses have suggested that the modern Central European gene pool is mainly of Palaeolithic origin. Surprisingly little attention has been paid to demographic aspects of the Neolithic transition. In our study, demographic simulations were performed to assess the demographic conditions that would allow LBK farmers to spread across central Europe without any admixture with Mesolithic foragers. We constructed a stochastic demographic model of changes in farming population size. Model parameters were constrained by data from human demography, archaeology, and human ecology. Our results indicate that the establishment of farming communities in Central Europe without an admixture with foragers was highly improbable. The demographic conditions necessary for colonization were beyond the potential of the Neolithic population. Our study supports the integrationists’ view of the Neolithic transition in Central Europe.

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

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Conn Jan E

2009-11-01

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

Visualising the demographic factors which shape population age structure

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Tom Wilson

2016-09-01

Full Text Available Background: The population pyramid is one of the most popular tools for visualising population age structure. However, it is difficult to discern from the diagram the relative effects of different demographic components on the size of age-specific populations, making it hard to understand exactly how a population's age structure is formed. Objective: The aim of this paper is to introduce a type of population pyramid which shows how births, deaths, and migration have shaped a population's age structure. Methods: Births, deaths, and population data were obtained from the Human Mortality Database and the Australian Bureau of Statistics. A variation on the conventional population pyramid, termed here a components-of-change pyramid, was created. Based on cohort population accounts, it illustrates how births, deaths, and net migration have created the population of each age group. A simple measure which summarises the impact of net migration on age structure is also suggested. Results: Example components-of-change pyramids for several countries and subnational regions are presented, which illustrate how births, deaths, and net migration have fashioned current population age structures. The influence of migration is shown to vary greatly between populations. Conclusions: The new type of pyramid aids interpretation of a population's age structure and helps to understand its demographic history over the last century.

From Farmers to Merchants, Voluntary Conversions and Diaspora: A Human Capital Interpretation of Jewish History

OpenAIRE

Botticini, Maristella; Eckstein, Zvi

2006-01-01

From the end of the second century C.E., Judaism enforced a religious norm requiring any Jewish father to educate his children. We present evidence supporting our thesis that this exogenous change in the religious and social norm had a major influence on Jewish economic and demographic history. First, the high individual and community cost of educating children in subsistence farming economies (2nd to 7th centuries) prompted voluntary conversions, which account for a large share of the reduct...

Climate change and human colonization triggered habitat loss and fragmentation in Madagascar

DEFF Research Database (Denmark)

Salmona, Jordi; Heller, Rasmus; Quéméré, Erwan

2017-01-01

The relative effect of past climate fluctuations and anthropogenic activities on current biome distribution is subject to increasing attention, notably in biodiversity hot spots. In Madagascar, where humans arrived in the last ~4 to 5,000 years, the exact causes of the demise of large vertebrates......-Holocene transition. While mid-Holocene climate change probably triggered major demographic changes in the two lemur species range and connectivity, human settlements that expanded over the last four millennia in northern Madagascar likely played a role in the loss and fragmentation of the forest cover.......—Propithecus tattersalli and Propithecus perrieri—using population genetic analyses. Our results highlight the necessity to consider population structure and changes in connectivity in demographic history inferences. We show that both species underwent demographic fluctuations which most likely occurred after the mid...

Recent and ongoing selection in the human genome

DEFF Research Database (Denmark)

Nielsen, Rasmus; Hellmann, Ines; Hubisz, Melissa

2007-01-01

The recent availability of genome-scale genotyping data has led to the identification of regions of the human genome that seem to have been targeted by selection. These findings have increased our understanding of the evolutionary forces that affect the human genome, have augmented our knowledge...... of gene function and promise to increase our understanding of the genetic basis of disease. However, inferences of selection are challenged by several confounding factors, especially the complex demographic history of human populations, and concordance between studies is variable. Although such studies...

The demographic dynamics of small island societies.

Science.gov (United States)

Cruz, M; D'ayala, P G; Marcus, E; Mcelroy, J L; Rossi, O

1987-01-01

Small islands and microstates have demonstrated a unique demographic pattern, including cycles of swift population increases or decreases well beyond natural birth and death rate balances. These demographic fluctuations have been produced largely by rises or declines in market opportunities. The process of taking advantage of favorable opportunities is always followed by a specialization in the given activity, without regard to environmental protection issues or a longterm strategy for economic development and resource diversification. The population growth phase is associated with increasing fragility of the economic base, whether because of the external dangers of overspecialization or induced internal dysfunctions such as disease and resource depletion. Eventually complete collapse results, causing chronic outmigration or even depopulation. Case histories of maritime basins in the Mediterranean, Caribbean, and Pacific show that the demographic structure of small islands has been particularly sensitive to changing economic opportunities, the vagaries of market forces, and cataclysmic natural events. Experience in these areas suggests that balanced economic development of small islands should be based on diversification of activities, thus ensuring a relatively stable pattern of growth, sound environmental management, and control of dangerous demographic fluctuations. Special attention should be given to the development of broad-based research and cooperation to integrate specific island opportunities within a regional network.

Spatial extent in demographic research - approach and problems

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Knežević Aleksandar

2015-01-01

Full Text Available One of the starting methodological problems in demographic research is the definition of spatial extent, which mostly doesn’t correspond to spatial extent already defined by different levels of administrative-territorial unitsthat are used for distribution of usable statistical data. That’s why determining the spatial extent of a demographic research is closely tied with administrative-territorial division of the territory that is being researched, wherein the fact that differentiation of demographic phenomena and processes cannot be the only basis of setting the principles of regionalization must be strictly acknowledged. This problem is particularly common in historical demographic analyses of geographically determined wholes, which are in administratively-territorial sense represented by one or more smaller territorial units, with their borders changing through the history, which directly affects comparability of the statistical data, and makes it considerably more difficult to track demographic change through longer time intervals. The result of these efforts is usually a solution based on a compromise which enables us to examine the dynamics of population change with little deviation from already defined borders of regional geographic wholes. For that reason in this paper the problem of defining spatial extent in demographic research is examined trough several different approaches in case of Eastern Serbia, as a geographically determined region, a historic area, a spatially functioning whole and as a statistical unit for demographic research, with no judgment calls in regard to any of the regionalization principles. [Projekat Ministarstva nauke Republike Srbije, br. III 47006

The history and composition of the Raymond A. Dart Collection of Human Skeletons at the University of the Witwatersrand, Johannesburg, South Africa.

Science.gov (United States)

Dayal, Manisha R; Kegley, Anthony D T; Strkalj, Goran; Bidmos, Mubarak A; Kuykendall, Kevin L

2009-10-01

The Raymond A. Dart Collection of Human Skeletons (Dart Collection) is housed in the School of Anatomical Sciences at the University of the Witwatersrand, Johannesburg, South Africa, and comprises one of the largest documented cadaver-derived human skeletal assemblages in the world. This collection originated in the early 1920s as a result of the efforts of Raymond Dart and continues to grow. The skeletons included represent varied indigenous and immigrant populations from southern Africa, Europe and Asia. This contribution documents the history of the collection and provides an updated inventory and demographic assessment of this valuable research collection. According to a recent inventory the Dart Collection currently comprises 2,605 skeletons representing individuals from regional SA African (76%), White (15%), Coloured (4%) and Indian (0.3%) populations. A large proportion of the skeletons (71%) represent males. The recorded ages at death range from the first year to over 100 years of age, but the majority of individuals died between the ages of 20 and 70. The Dart Collection has been affected by collection procedures based on availability. All of the cadavers collected before 1958, and large proportions subsequently, were derived from unclaimed bodies in regional South African hospitals. Some details of documentation (age at death, population group) are estimates and some aspects of the collection demographics (sex ratios) do not closely reflect any living South African population. Our inventory and analysis of the Dart Collection is aimed to assist researchers planning research on the materials from this collection.

Demographical history and palaeodistribution modelling show range shift towards Amazon Basin for a Neotropical tree species in the LGM.

Science.gov (United States)

Vitorino, Luciana Cristina; Lima-Ribeiro, Matheus S; Terribile, Levi Carina; Collevatti, Rosane G

2016-10-13

We studied the phylogeography and demographical history of Tabebuia serratifolia (Bignoniaceae) to understand the disjunct geographical distribution of South American seasonally dry tropical forests (SDTFs). We specifically tested if the multiple and isolated patches of SDTFs are current climatic relicts of a widespread and continuously distributed dry forest during the last glacial maximum (LGM), the so called South American dry forest refugia hypothesis, using ecological niche modelling (ENM) and statistical phylogeography. We sampled 235 individuals of T. serratifolia in 17 populations in Brazil and analysed the polymorphisms at three intergenic chloroplast regions and ITS nuclear ribosomal DNA. Coalescent analyses showed a demographical expansion at the last c. 130 ka (thousand years before present). Simulations and ENM also showed that the current spatial pattern of genetic diversity is most likely due to a scenario of range expansion and range shift towards the Amazon Basin during the colder and arid climatic conditions associated with the LGM, matching the expected for the South American dry forest refugia hypothesis, although contrasting to the Pleistocene Arc hypothesis. Populations in more stable areas or with higher suitability through time showed higher genetic diversity. Postglacial range shift towards the Southeast and Atlantic coast may have led to spatial genome assortment due to leading edge colonization as the species tracks suitable environments, leading to lower genetic diversity in populations at higher distance from the distribution centroid at 21 ka. Haplotype sharing or common ancestry among populations from Caatinga in Northeast Brazil, Atlantic Forest in Southeast and Cerrado biome and ENM evince the past connection among these biomes.

Implications of research staff demographics for psychological science.

Science.gov (United States)

Does, Serena; Ellemers, Naomi; Dovidio, John F; Norman, Jasmine B; Mentovich, Avital; van der Lee, Romy; Goff, Phillip Atiba

2018-03-01

Long-standing research traditions in psychology have established the fundamental impact of social categories, such as race and gender, on people's perceptions of themselves and others, as well as on the general human cognition and behavior. However, there is a general tendency to ignore research staff demographics (e.g., researchers' race and gender) in research development and research reports. Variation in research staff demographics can exert systematic and scientifically informative influences on results from psychological research. Consequently, research staff demographics need to be considered, studied, and/or reported, along with how these demographics were allowed to vary across participants or conditions (e.g., random assignment, matched with participant demographics, or included as a factor in the experimental design). In addition to providing an overview of multidisciplinary evidence of research staff demographics effects, we discuss how research staff demographics might influence research findings through (a) ingroup versus outgroup effects, (b) stereotype and (implicit) bias effects, and (c) priming and social tuning effects. Finally, an overview of recommended considerations is included (see the Appendix) to help illustrate how to systematically incorporate relevant research staff demographics in psychological science. (PsycINFO Database Record (c) 2018 APA, all rights reserved).

Cross-cultural Comparison of Learning in Human Hunting : Implications for Life History Evolution.

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MacDonald, Katharine

2007-12-01

This paper is a cross-cultural examination of the development of hunting skills and the implications for the debate on the role of learning in the evolution of human life history patterns. While life history theory has proven to be a powerful tool for understanding the evolution of the human life course, other schools, such as cultural transmission and social learning theory, also provide theoretical insights. These disparate theories are reviewed, and alternative and exclusive predictions are identified. This study of cross-cultural regularities in how children learn hunting skills, based on the ethnographic literature on traditional hunters, complements existing empirical work and highlights future areas for investigation.

Contemporary genetic structure and postglacial demographic history of the black scorpionfish, Scorpaena porcus, in the Mediterranean and the Black Seas.

Science.gov (United States)

Boissin, E; Micu, D; Janczyszyn-Le Goff, M; Neglia, V; Bat, L; Todorova, V; Panayotova, M; Kruschel, C; Macic, V; Milchakova, N; Keskin, Ç; Anastasopoulou, A; Nasto, I; Zane, L; Planes, S

2016-05-01

Understanding the distribution of genetic diversity in the light of past demographic events linked with climatic shifts will help to forecast evolutionary trajectories of ecosystems within the current context of climate change. In this study, mitochondrial sequences and microsatellite loci were analysed using traditional population genetic approaches together with Bayesian dating and the more recent approximate Bayesian computation scenario testing. The genetic structure and demographic history of a commercial fish, the black scorpionfish, Scorpaena porcus, was investigated throughout the Mediterranean and Black Seas. The results suggest that the species recently underwent population expansions, in both seas, likely concomitant with the warming period following the Last Glacial Maximum, 20 000 years ago. A weak contemporaneous genetic differentiation was identified between the Black Sea and the Mediterranean Sea. However, the genetic diversity was similar for populations of the two seas, suggesting a high number of colonizers entered the Black Sea during the interglacial period and/or the presence of a refugial population in the Black Sea during the glacial period. Finally, within seas, an east/west genetic differentiation in the Adriatic seems to prevail, whereas the Black Sea does not show any structured spatial genetic pattern of its population. Overall, these results suggest that the Black Sea is not that isolated from the Mediterranean, and both seas revealed similar evolutionary patterns related to climate change and changes in sea level. © 2016 John Wiley & Sons Ltd.

Demographic Structural Theory: 25 Years On

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Jack A. Goldstone

2017-12-01

Full Text Available I am grateful to Cliodynamics for this special issue revisiting the ideas put forth in Revolution and Rebellion in the Early Modern World (Goldstone 1991, 2016 a quarter century ago. The two things that one could hope for in advancing any theory are that it proves capable of being advanced and enriched by other scholars, and that it proves capable of being applied in new ways and to new phenomena that were not anticipated. This issue gives examples of both, and shows how scholars are even now only beginning to tap the possibilities of Demographic Structural Theory (DST in explaining politics, history, and long-term economic trends. In this essay, I will tell the story of how demographic structural theory was conceived, relate its early reception among scholars, and comment on the important contributions by other scholars to this special issue.

Distinguishing bipolar II depression from major depressive disorder with comorbid borderline personality disorder: demographic, clinical, and family history differences.

Science.gov (United States)

Zimmerman, Mark; Martinez, Jennifer H; Morgan, Theresa A; Young, Diane; Chelminski, Iwona; Dalrymple, Kristy

2013-09-01

Because of the potential treatment implications, it is clinically important to distinguish between bipolar II depression and major depressive disorder with comorbid borderline personality disorder. The high frequency of diagnostic co-occurrence and resemblance of phenomenological features has led some authors to suggest that borderline personality disorder is part of the bipolar spectrum. Few studies have directly compared patients with bipolar disorder and borderline personality disorder. In the present study from the Rhode Island Methods to Improve Diagnostic Assessment and Services project, we compared these 2 groups of patients on demographic, clinical, and family history variables. From December 1995 to May 2012, 3,600 psychiatric patients presenting to the outpatient practice at Rhode Island Hospital (Providence, Rhode Island) were evaluated with semistructured diagnostic interviews for DSM-IV Axis I and Axis II disorders. The focus of the present study is the 206 patients with DSM-IV major depressive disorder and borderline personality disorder (MDD-BPD) and 62 patients with DSM-IV bipolar II depression without borderline personality disorder. The patients with MDD-BPD were significantly more often diagnosed with posttraumatic stress disorder (P depression had a significantly higher morbid risk for bipolar disorder in their first-degree relatives than the MDD-BPD patients (P depression and major depressive disorder with comorbid borderline personality disorder differed on a number of clinical and family history variables, thereby supporting the validity of this distinction. © Copyright 2013 Physicians Postgraduate Press, Inc.

Genetic stratigraphy of key demographic events in Arabia.

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

2015-01-01

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

HOW HUMAN HISTORY HAS INFLUENCED GEOGRAPHY AND GENETICS OF PARASITE POPULATIONS

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Human beings have radically altered agricultural landscapes, establishing a limited repertoire of plants and animals over vast expanses. Here, I consider what impact such a history may have had on the distribution and diversity of animal parasite, hypothesizing that certain parasites may have been '...

Modeling the Temporal Nature of Human Behavior for Demographics Prediction

DEFF Research Database (Denmark)

Felbo, Bjarke; Sundsøy, Pål; Pentland, Alex

2017-01-01

Mobile phone metadata is increasingly used for humanitarian purposes in developing countries as traditional data is scarce. Basic demographic information is however often absent from mobile phone datasets, limiting the operational impact of the datasets. For these reasons, there has been a growing...... interest in predicting demographic information from mobile phone metadata. Previous work focused on creating increasingly advanced features to be modeled with standard machine learning algorithms. We here instead model the raw mobile phone metadata directly using deep learning, exploiting the temporal...... on both age and gender prediction using only the temporal modality in mobile metadata. We finally validate our method on low activity users and evaluate the modeling assumptions....

The Juvenile Transition: A Developmental Switch Point in Human Life History

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Del Giudice, Marco; Angeleri, Romina; Manera, Valeria

2009-01-01

This paper presents a new perspective on the transition from early to middle childhood (i.e., human juvenility), investigated in an integrative evolutionary framework. Juvenility is a crucial life history stage, when social learning and interaction with peers become central developmental functions; here it is argued that the "juvenile transition"…

The history of science as the progress of the human spirit: The historiography of astronomy in the eighteenth century.

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Špelda, Daniel

2017-06-01

In the eighteenth century, the historiography of astronomy was part of a wider discussion concerning the history of the human spirit. The concept of the human spirit was very popular among Enlightenment authors because it gave the history of human knowledge continuity, unity and meaning. Using this concept, scientists and historians of science such as Montucla, Lalande, Bailly and Laplace could present the history of astronomy in terms of a progress towards contemporary science that was slow and could be interrupted at times, but was still constant, regular, and necessary. In my paper I intend to explain how the originally philosophical concept of the human spirit was transferred to the history of astronomy. I also introduce the basic principles to which the development of the spirit is subject in astronomy, according to historians of astronomy. The third part of the paper describes how historians of astronomy took into account the effect of social and natural factors on the history of astronomy. Copyright © 2017 Elsevier Ltd. All rights reserved.

Increased mortality exposure within the family rather than individual mortality experiences triggers faster life-history strategies in historic human populations.

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Störmer, Charlotte; Lummaa, Virpi

2014-01-01

Life History Theory predicts that extrinsic mortality risk is one of the most important factors shaping (human) life histories. Evidence from contemporary populations suggests that individuals confronted with high mortality environments show characteristic traits of fast life-history strategies: they marry and reproduce earlier, have shorter birth intervals and invest less in their offspring. However, little is known of the impact of mortality experiences on the speed of life histories in historical human populations with generally higher mortality risk, and on male life histories in particular. Furthermore, it remains unknown whether individual-level mortality experiences within the family have a greater effect on life-history decisions or family membership explains life-history variation. In a comparative approach using event history analyses, we study the impact of family versus individual-level effects of mortality exposure on two central life-history parameters, ages at first marriage and first birth, in three historical human populations (Germany, Finland, Canada). Mortality experience is measured as the confrontation with sibling deaths within the natal family up to an individual's age of 15. Results show that the speed of life histories is not adjusted according to individual-level mortality experiences but is due to family-level effects. The general finding of lower ages at marriage/reproduction after exposure to higher mortality in the family holds for both females and males. This study provides evidence for the importance of the family environment for reproductive timing while individual-level mortality experiences seem to play only a minor role in reproductive life history decisions in humans.

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

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

2012-01-01

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

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

Science.gov (United States)

Rotella, Jay J; Link, William A; Chambert, Thierry; Stauffer, Glenn E; Garrott, Robert A

2012-01-01

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

Environmental imperatives reconsidered: demographic crises in western North America during the medieval climatic anomaly.

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Jones, T L; Brown, G M; Raab, L M; McVickar, J L; Spaulding, W G; Kennett, D J; York, A; Wlaker, P L

1999-04-01

Review of late Holocene paleoenvironmental and cultural sequences from four regions of western North America show striking correlations between drought and changes in subsistence, population, exchange, health, and interpersonal violence during the Medieval Climatic Anomaly (A.D. 800-1350). While ultimate causality is difficult to identify in the archaeological record, synchrony of the environmental and cultural changes and the negative character of many human responses--increased interpersonal violence, deterioration of long-distance exchange relationships, and regional abandonments--suggest widespread demographic crises caused by decreased environmental productivity. The medieval droughts occurred at a unique juncture in the demographic history of western North America when unusually large populations of both hunter-gathers and agriculturalists had evolved highly intensified economies that put them in unprecedented ecological jeopardy. Long-term patterns in the archaeological record are inconsistent with the predicted outcomes of simple adaptation or continuous economic intensification, suggesting that in this instance environmental dynamics played a major role in cultural transformations across a wide expanse of western North America among groups with diverse subsistence strategies. These events suggest that environment should not be overlooked as a potential cause of prehistoric culture change.

The Driving Forces of Cultural Complexity : Neanderthals, Modern Humans, and the Question of Population Size.

Science.gov (United States)

Fogarty, Laurel; Wakano, Joe Yuichiro; Feldman, Marcus W; Aoki, Kenichi

2017-03-01

The forces driving cultural accumulation in human populations, both modern and ancient, are hotly debated. Did genetic, demographic, or cognitive features of behaviorally modern humans (as opposed to, say, early modern humans or Neanderthals) allow culture to accumulate to its current, unprecedented levels of complexity? Theoretical explanations for patterns of accumulation often invoke demographic factors such as population size or density, whereas statistical analyses of variation in cultural complexity often point to the importance of environmental factors such as food stability, in determining cultural complexity. Here we use both an analytical model and an agent-based simulation model to show that a full understanding of the emergence of behavioral modernity, and the cultural evolution that has followed, depends on understanding and untangling the complex relationships among culture, genetically determined cognitive ability, and demographic history. For example, we show that a small but growing population could have a different number of cultural traits from a shrinking population with the same absolute number of individuals in some circumstances.

Bone health history in breast cancer patients on aromatase inhibitors.

Directory of Open Access Journals (Sweden)

Marilyn L Kwan

Full Text Available A cross-sectional study was performed to assess bone health history among aromatase inhibitor (AI users before breast cancer (BC diagnosis, which may impact fracture risk after AI therapy and choice of initial hormonal therapy. A total of 2,157 invasive BC patients initially treated with an AI were identified from a prospective cohort study at Kaiser Permanente Northern California (KPNC. Data on demographic and lifestyle factors were obtained from in-person interviews, and bone health history and clinical data from KPNC clinical databases. The prevalence of osteoporosis and fractures in postmenopausal AI users was assessed, compared with 325 postmenopausal TAM users. The associations of bone health history with demographic and lifestyle factors in AI users were also examined. Among all initial AI users, 11.2% had a prior history of osteoporosis, 16.3% had a prior history of any fracture, and 4.6% had a prior history of major fracture. Postmenopausal women who were taking TAM as their initial hormonal therapy had significantly higher prevalence of prior osteoporosis than postmenopausal AI users (21.5% vs. 11.8%, p<0.0001. Among initial AI users, the associations of history of osteoporosis and fracture in BC patients with demographic and lifestyle factors were, in general, consistent with those known in healthy older women. This study is one of the first to characterize AI users and risk factors for bone morbidity before BC diagnosis. In the future, this study will examine lifestyle, molecular, and genetic risk factors for AI-induced fractures.

How well can body size represent effects of the environment on demographic rates? Disentangling correlated explanatory variables.

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Brooks, Mollie E; Mugabo, Marianne; Rodgers, Gwendolen M; Benton, Timothy G; Ozgul, Arpat

2016-03-01

Demographic rates are shaped by the interaction of past and current environments that individuals in a population experience. Past environments shape individual states via selection and plasticity, and fitness-related traits (e.g. individual size) are commonly used in demographic analyses to represent the effect of past environments on demographic rates. We quantified how well the size of individuals captures the effects of a population's past and current environments on demographic rates in a well-studied experimental system of soil mites. We decomposed these interrelated sources of variation with a novel method of multiple regression that is useful for understanding nonlinear relationships between responses and multicollinear explanatory variables. We graphically present the results using area-proportional Venn diagrams. Our novel method was developed by combining existing methods and expanding upon them. We showed that the strength of size as a proxy for the past environment varied widely among vital rates. For instance, in this organism with an income breeding life history, the environment had more effect on reproduction than individual size, but with substantial overlap indicating that size encompassed some of the effects of the past environment on fecundity. This demonstrates that the strength of size as a proxy for the past environment can vary widely among life-history processes within a species, and this variation should be taken into consideration in trait-based demographic or individual-based approaches that focus on phenotypic traits as state variables. Furthermore, the strength of a proxy will depend on what state variable(s) and what demographic rate is being examined; that is, different measures of body size (e.g. length, volume, mass, fat stores) will be better or worse proxies for various life-history processes. © 2016 The Authors. Journal of Animal Ecology © 2016 British Ecological Society.

A Statistical Assessment of Demographic Bonus towards Poverty Alleviation

Directory of Open Access Journals (Sweden)

Jamal Abdul Nasir

2011-09-01

Full Text Available The shift of birth and death rates from high to low level in any population is referred as demographic transition. Mechanically, the transition of a society creates more working member of its own population commonly called demographic bonus. This articleempirically explores the realistic soundness of demographic bonus in reducing the poverty level of the society. Three contrasting regions namely Eastern Asia, Central America and Oceania were selected for analytical purposes. The findings indicate that Eastern Asia and Oceania are currently facing the end of their transition whereas theCentral America is lagged behind in transition. Central America due to last runner in transition race is the sustained recipient of its own demographic bonus by the year 2030.On the basis of three mechanisms namely: labour supply, savings and human capital, the Eastern Asian region is found to be successful beneficiary of its own demographic gift which concludes that many million people have escaped from poverty. Under the right policy environment on the above three mechanisms, Eastern Asia experience indicates the realistic contribution of demographic bonus to reduce poverty.

Language and life history: a new perspective on the development and evolution of human language.

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Locke, John L; Bogin, Barry

2006-06-01

It has long been claimed that Homo sapiens is the only species that has language, but only recently has it been recognized that humans also have an unusual pattern of growth and development. Social mammals have two stages of pre-adult development: infancy and juvenility. Humans have two additional prolonged and pronounced life history stages: childhood, an interval of four years extending between infancy and the juvenile period that follows, and adolescence, a stage of about eight years that stretches from juvenility to adulthood. We begin by reviewing the primary biological and linguistic changes occurring in each of the four pre-adult ontogenetic stages in human life history. Then we attempt to trace the evolution of childhood and juvenility in our hominin ancestors. We propose that several different forms of selection applied in infancy and childhood; and that, in adolescence, elaborated vocal behaviors played a role in courtship and intrasexual competition, enhancing fitness and ultimately integrating performative and pragmatic skills with linguistic knowledge in a broad faculty of language. A theoretical consequence of our proposal is that fossil evidence of the uniquely human stages may be used, with other findings, to date the emergence of language. If important aspects of language cannot appear until sexual maturity, as we propose, then a second consequence is that the development of language requires the whole of modern human ontogeny. Our life history model thus offers new ways of investigating, and thinking about, the evolution, development, and ultimately the nature of human language.

Do people with intellectual disability require special human subjects research protections? The interplay of history, ethics, and policy.

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Feudtner, Chris; Brosco, Jeffrey P

2011-01-01

People with intellectual disability (ID) have a long history of discrimination and stigmatization, and a more recent history of pride and self-advocacy. The early history suggests that people with ID are a vulnerable population and deserve special research protections as do some other groups; the disability rights movement of the late 20th century aligns people with ID more closely with the principle of autonomy that has guided clinical and research ethics for the last 40 years. In examining the history of people with ID and the prevailing framework of human subjects research protections in the United States, we conclude that people with ID do not require special protection in human subjects research. The protections that have already been put in place for all individuals, if conscientiously and effectively implemented, achieve the right balance between safeguarding the interest of human research subjects and empowering individuals who choose to do so to participate in research. Copyright © 2012 Wiley Periodicals, Inc.

History of human papillomavirus, warts and cancer: what do we know today?

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Onon, Toli S

2011-10-01

Human papillomavirus has been a cause of infection in humans for thousands of years. The history of papillomaviruses, knowledge of their causative role in benign and malignant disease, and their structural characteristics have led to the development of vaccines to prevent cervical and anogenital cancers. Many questions remain unanswered before HPV vaccines can be optimised; however, the concept of virtual eradication of cervical cancer is not impossible, and remains a realistic aspiration. Copyright © 2011 Elsevier Ltd. All rights reserved.

Understanding variation in human fertility: what can we learn from evolutionary demography?

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Sear, Rebecca; Lawson, David W; Kaplan, Hillard; Shenk, Mary K

2016-04-19

Decades of research on human fertility has presented a clear picture of how fertility varies, including its dramatic decline over the last two centuries in most parts of the world. Why fertility varies, both between and within populations, is not nearly so well understood. Fertility is a complex phenomenon, partly physiologically and partly behaviourally determined, thus an interdisciplinary approach is required to understand it. Evolutionary demographers have focused on human fertility since the 1980s. The first wave of evolutionary demographic research made major theoretical and empirical advances, investigating variation in fertility primarily in terms of fitness maximization. Research focused particularly on variation within high-fertility populations and small-scale subsistence societies and also yielded a number of hypotheses for why fitness maximization seems to break down as fertility declines during the demographic transition. A second wave of evolutionary demography research on fertility is now underway, paying much more attention to the cultural and psychological mechanisms underpinning fertility. It is also engaging with the complex, multi-causal nature of fertility variation, and with understanding fertility in complex modern and transitioning societies. Here, we summarize the history of evolutionary demographic work on human fertility, describe the current state of the field, and suggest future directions. © 2016 The Author(s).

CCA 3101/4101 Environmental Humanities: The History of a Unit through an Ecopedagogical Lens

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Ryan, John Charles

2012-01-01

In 2011 the author taught, for the first time, the well-established unit CCA3101/4101 Environmental Humanities in the School of Communications and Arts at ECU (Edith Cowan University) in Western Australia. The unit has a 20-year history through associate professor Rod Giblett and parallels the development of the environmental humanities as a field…

Predicting primate responses to "Stochastic" demographic events.

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Strier, K B

1999-01-01

Comparative approaches in contemporary primate behavioral ecology have tended to emphasize the deterministic properties of stochastic ecological variables. Yet, primate responses to ecological fluctuations may be mediated by the interactions among demographic processes at the levels of individuals, groups, and populations. In this paper I examine long-term data collected from June 1982-July 1998 on one expanding group of muriquis (Brachyteles arachnoides) at the Estação Biologica de Caratinga, Minas Gerais, Brazil to explore the demographic and life history correlates of reproductive seasonality and skewed infant sex ratios. Variation in the size of annual birth cohorts (≥2 infants) was positively related to variation in the annual distribution of births (r (s)=0.96,n=10,p<0.01), indicating the importance of considering the effects that the number of reproductive females may have on interpretations of reproductive seasonality. The female-biased infants sex ratio documented from 59 births was attributed exclusively to multiparous mothers. Primiparous mothers produced comparable numbers of sons (n=6) and daughters (n=7), and were increasingly likely to produce daughters with each subsequent reproductive event. Seven of the 11 females that have produced≥3 infants to date exhibited biases in favor of daughters whereas only 1 was biased in favor of sons. Variation in female sensitivity to local resource competition at different stages of their life histories may account for the female-biased infant sex ration in this population.

History of Smallpox and Its Spread in Human Populations.

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Thèves, Catherine; Crubézy, Eric; Biagini, Philippe

2016-08-01

Smallpox is considered among the most devastating of human diseases. Its spread in populations, initiated for thousands of years following a probable transmission from an animal host, was concomitant with movements of people across regions and continents, trade and wars. Literature permitted to retrace the occurrence of epidemics from ancient times to recent human history, smallpox having affected all levels of past society including famous monarchs. The disease was officially declared eradicated in 1979 following intensive vaccination campaigns.Paleomicrobiology dedicated to variola virus is restricted to few studies, most unsuccessful, involving ancient material. Only one recent approach allowed the identification of viral DNA fragments from lung tissue of a 300-year-old body excavated from permafrost in Eastern Siberia; phylogenetic analysis revealed that this ancient strain was distinct from those described during the 20th century.

Genetic diversity and structure related to expansion history and habitat isolation: stone marten populating rural-urban habitats.

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Wereszczuk, Anna; Leblois, Raphaël; Zalewski, Andrzej

2017-12-22

Population genetic diversity and structure are determined by past and current evolutionary processes, among which spatially limited dispersal, genetic drift, and shifts in species distribution boundaries have major effects. In most wildlife species, environmental modifications by humans often lead to contraction of species' ranges and/or limit their dispersal by acting as environmental barriers. However, in species well adapted to anthropogenic habitat or open landscapes, human induced environmental changes may facilitate dispersal and range expansions. In this study, we analysed whether isolation by distance and deforestation, among other environmental features, promotes or restricts dispersal and expansion in stone marten (Martes foina) populations. We genotyped 298 martens from eight sites at twenty-two microsatellite loci to characterize the genetic variability, population structure and demographic history of stone martens in Poland. At the landscape scale, limited genetic differentiation between sites in a mosaic of urban, rural and forest habitats was mostly influenced by isolation by distance. Statistical clustering and multivariate analyses showed weak genetic structuring with two to four clusters and a high rate of gene flow between them. Stronger genetic differentiation was detected for one stone marten population (NE1) located inside a large forest complex. Genetic differentiation between this site and all others was 20% higher than between other sites separated by similar distances. The genetic uniqueness index of NE1 was also twofold higher than in other sites. Past demographic history analyses showed recent expansion of this species in north-eastern Poland. A decrease in genetic diversity from south to north, and MIGRAINE analyses indicated the direction of expansion of stone marten. Our results showed that two processes, changes in species distribution boundaries and limited dispersal associated with landscape barriers, affect genetic diversity and

History matching of a complex epidemiological model of human immunodeficiency virus transmission by using variance emulation.

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Andrianakis, I; Vernon, I; McCreesh, N; McKinley, T J; Oakley, J E; Nsubuga, R N; Goldstein, M; White, R G

2017-08-01

Complex stochastic models are commonplace in epidemiology, but their utility depends on their calibration to empirical data. History matching is a (pre)calibration method that has been applied successfully to complex deterministic models. In this work, we adapt history matching to stochastic models, by emulating the variance in the model outputs, and therefore accounting for its dependence on the model's input values. The method proposed is applied to a real complex epidemiological model of human immunodeficiency virus in Uganda with 22 inputs and 18 outputs, and is found to increase the efficiency of history matching, requiring 70% of the time and 43% fewer simulator evaluations compared with a previous variant of the method. The insight gained into the structure of the human immunodeficiency virus model, and the constraints placed on it, are then discussed.

Out-of-Africa migration and Neolithic coexpansion of Mycobacterium tuberculosis with modern humans.

Science.gov (United States)

Comas, Iñaki; Coscolla, Mireia; Luo, Tao; Borrell, Sonia; Holt, Kathryn E; Kato-Maeda, Midori; Parkhill, Julian; Malla, Bijaya; Berg, Stefan; Thwaites, Guy; Yeboah-Manu, Dorothy; Bothamley, Graham; Mei, Jian; Wei, Lanhai; Bentley, Stephen; Harris, Simon R; Niemann, Stefan; Diel, Roland; Aseffa, Abraham; Gao, Qian; Young, Douglas; Gagneux, Sebastien

2013-10-01

Tuberculosis caused 20% of all human deaths in the Western world between the seventeenth and nineteenth centuries and remains a cause of high mortality in developing countries. In analogy to other crowd diseases, the origin of human tuberculosis has been associated with the Neolithic Demographic Transition, but recent studies point to a much earlier origin. We analyzed the whole genomes of 259 M. tuberculosis complex (MTBC) strains and used this data set to characterize global diversity and to reconstruct the evolutionary history of this pathogen. Coalescent analyses indicate that MTBC emerged about 70,000 years ago, accompanied migrations of anatomically modern humans out of Africa and expanded as a consequence of increases in human population density during the Neolithic period. This long coevolutionary history is consistent with MTBC displaying characteristics indicative of adaptation to both low and high host densities.

Human radiation studies: Remembering the early years. Oral history of Biochemist Waldo E. Cohn, Ph.D

International Nuclear Information System (INIS)

1995-01-01

In September 1994, the Department of Energy began an oral history project as part of the Openess initiative on the documentation of the human radiation experiments. This paper presents the oral history of Waldo E Cohn, Ph.D., a Biochemist who worked for the Oak Ridge National Laboratory and the Manhattan Project

History Classroom Interactions and the Transmission of the Recent Memory of Human Rights Violations in Chile

Science.gov (United States)

Oteíza, Teresa; Henríquez, Rodrigo; Pinuer, Claudio

2015-01-01

The purpose of this article is to examine history classroom interactions in Chilean secondary schools in relation to the transmission of historical memories of human rights violations committed by Augusto Pinochet's dictatorship from 1973 to 1990. Corpora of this research are comprised of history lessons filmed in the two types of public schools…

[Hepatitis: a longstanding companion in human history].

Science.gov (United States)

Craxi, Lucia

2012-03-01

Hepatitis has gone along with human history since its origins, due to its prompt identifiability linked to jaundice as a symptom. Written evidence of outbreaks of epidemic jaundice can be tracked back a few millenniums before Christ. Unavoidable confusion arises due to the overlap of different sources possibly linked to different aetiologies, identified over time as epidemic jaundice (HAV or HEV hepatitis?) and serum hepatitis (HBV or HCV hepatitis?). The journey that brought to recognize viruses as the main cause of jaundice was long and started midway during the last century, when the infectious hypothesis, which had taken place step by step, was finally confirmed by epidemiological investigations of an outbreak occurring in the US army in 1942, after a yellow fever immunization campaign. Further research identified two clinically different types of hepatitis, called for the first time hepatitis A and hepatitis B.

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

Science.gov (United States)

Elias, Scott A

2014-01-01

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

The environmental context of human evolutionary history in Eurasia and Africa.

Science.gov (United States)

Elton, Sarah

2008-04-01

This review has three main aims: (1) to make specific predictions about the habitat of the hypothetical last common ancestor of the chimpanzee/bonobo-human clade; (2) to outline the major trends in environments between 8-6 Ma and the late Pleistocene; and (3) to pinpoint when, and in some cases where, human ancestors evolved to cope with the wide range of habitats they presently tolerate. Several lines of evidence indicate that arboreal environments, particularly woodlands, were important habitats for late Miocene hominids and hominins, and therefore possibly for the last common ancestor of the chimpanzee/bonobo-human clade. However, as there is no clear candidate for this last common ancestor, and because the sampling of fossils and past environments is inevitably patchy, this prediction remains a working hypothesis at best. Nonetheless, as a primate, it is expected that the last common ancestor was ecologically dependent on trees in some form. Understanding past environments is important, as palaeoenvironmental reconstructions provide the context for human morphological and behavioural evolution. Indeed, the impact of climate on the evolutionary history of our species has long been debated. Since the mid-Miocene, the Earth has been experiencing a general cooling trend accompanied by aridification, which intensified during the later Pliocene and Pleistocene. Numerous climatic fluctuations, as well as local, regional and continental geography that influenced weather patterns and vegetation, created hominin environments that were dynamic in space and time. Behavioural flexibility and cultural complexity were crucial aspects of hominin expansion into diverse environments during the Pleistocene, but the ability to exploit varied and varying habitats was established much earlier in human evolutionary history. The development of increasingly complex tool technology facilitated re-expansion into tropical forests. These environments are difficult for obligate bipeds to

A personal history of the human exploration initiative with commentary on the pivotal role for life support research

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Mendell, Wendell

1990-01-01

The author relates the history of the human exploration initiative from a personal perspective from the 1961 J. F. Kennedy initiative to land a man on the moon up to 1986 when a memo was circulated from NASA Headquarters to its employees which stated as a major goal the expansion of the human presence beyond Earth into the solar system. The pivotal role of life support research is woven into this personalized history.

Viral Causes of Lymphoma: The History of Epstein-Barr Virus and Human T-Lymphotropic Virus 1.

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Esau, Daniel

2017-01-01

In 1964, Epstein, Barr, and Achong published a report outlining their discovery of viral particles in lymphoblasts isolated from a patient with Burkitt lymphoma. The Epstein-Barr virus (EBV) was the first human cancer virus to be described, and its discovery paved the way for further investigations into the oncogenic potential of viruses. In the decades following the discovery of EBV, multinational research efforts led to the discovery of further viral causes of various human cancers. Lymphomas are perhaps the cancer type that is most closely associated with oncogenic viruses: infection with EBV, human T-lymphotropic virus 1 (HTLV-1), human immunodeficiency virus (HIV), Kaposi sarcoma-associated herpesvirus/human herpesvirus 8, and hepatitis C virus have all been associated with lymphomagenesis. Lymphomas have also played an important role in the history of oncoviruses, as both the first human oncovirus (EBV) and the first human retrovirus (HTLV-1) were discovered through isolates taken from patients with unique lymphoma syndromes. The history of the discovery of these 2 key oncoviruses is presented here, and their impact on further medical research, using the specific example of HIV research, is briefly discussed.

Viral Causes of Lymphoma: The History of Epstein-Barr Virus and Human T-Lymphotropic Virus 1

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Daniel Esau

2017-09-01

Full Text Available In 1964, Epstein, Barr, and Achong published a report outlining their discovery of viral particles in lymphoblasts isolated from a patient with Burkitt lymphoma. The Epstein-Barr virus (EBV was the first human cancer virus to be described, and its discovery paved the way for further investigations into the oncogenic potential of viruses. In the decades following the discovery of EBV, multinational research efforts led to the discovery of further viral causes of various human cancers. Lymphomas are perhaps the cancer type that is most closely associated with oncogenic viruses: infection with EBV, human T-lymphotropic virus 1 (HTLV-1, human immunodeficiency virus (HIV, Kaposi sarcoma-associated herpesvirus/human herpesvirus 8, and hepatitis C virus have all been associated with lymphomagenesis. Lymphomas have also played an important role in the history of oncoviruses, as both the first human oncovirus (EBV and the first human retrovirus (HTLV-1 were discovered through isolates taken from patients with unique lymphoma syndromes. The history of the discovery of these 2 key oncoviruses is presented here, and their impact on further medical research, using the specific example of HIV research, is briefly discussed.

Reduced costs of reproduction in females mediate a shift from a male-biased to a female-biased lifespan in humans

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Bolund, Elisabeth; Lummaa, Virpi; Smith, Ken R.; Hanson, Heidi A.; Maklakov, Alexei A.

2016-01-01

The causes underlying sex differences in lifespan are strongly debated. While females commonly outlive males in humans, this is generally less pronounced in societies before the demographic transition to low mortality and fertility rates. Life-history theory suggests that reduced reproduction should benefit female lifespan when females pay higher costs of reproduction than males. Using unique longitudinal demographic records on 140,600 reproducing individuals from the Utah Population Database, we demonstrate a shift from male-biased to female-biased adult lifespans in individuals born before versus during the demographic transition. Only women paid a cost of reproduction in terms of shortened post-reproductive lifespan at high parities. Therefore, as fertility decreased over time, female lifespan increased, while male lifespan remained largely stable, supporting the theory that differential costs of reproduction in the two sexes result in the shifting patterns of sex differences in lifespan across human populations. Further, our results have important implications for demographic forecasts in human populations and advance our understanding of lifespan evolution. PMID:27087670

A Personal Account of the History of Historical Demography in Europe at the End of the Glorious Thirty (1967-1975

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Antoinette Fauve-Chamoux

2017-04-01

Full Text Available Encouraged by her masters at the Annales School—historians Fernand Braudel and Emmanuel Le Roy Ladurie, demographer Louis Henry from Institut National d’Etudes Démographiques (INED, and sociologist Peter Laslett from Cambridge—the author, a baby-boomer, experienced major socio-economic and cultural changes in family behavior and reproduction models induced in Europe by the revolutionary events of 1968 in Paris. In this essay, she presents a personal account of the history of historical demography in Europe, between 1967 and 1975, in other words at the end of the post-WWII Glorious Thirty period (1945-1975. She then became involved in the development of a global network that had been formed in 1960 in Stockholm, linking professional national and international associations and academic units in Historical Demography and History of the Family. This network spread quickly overseas during the following decades. The period under study was marked by the beginning of important behavioral changes in socio-economic contexts and attitudes to family life, gender and human reproduction. These major shifts were called the Second Demographic Transition by two Dutch demographers, inspired by French scholars. The year 1976 is identified as a major turning point for Historical Demography as a discipline, mostly through the creation of the Social Science History Association and the Journal of Family History, which brought new theoretical approaches and methodologies. A generation of productive researchers appeared with the end of the 20th century and the new millennium. They took advantage of an increasingly digitalized world to widely disseminate a rich store of knowledge about past population behavior gathered since the 1960s by their predecessors.

Genetic structure and invasion history of the house mouse (Mus musculus domesticus) in Senegal, West Africa: a legacy of colonial and contemporary times.

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Lippens, C; Estoup, A; Hima, M K; Loiseau, A; Tatard, C; Dalecky, A; Bâ, K; Kane, M; Diallo, M; Sow, A; Niang, Y; Piry, S; Berthier, K; Leblois, R; Duplantier, J-M; Brouat, C

2017-08-01

Knowledge of the genetic make-up and demographic history of invasive populations is critical to understand invasion mechanisms. Commensal rodents are ideal models to study whether complex invasion histories are typical of introductions involving human activities. The house mouse Mus musculus domesticus is a major invasive synanthropic rodent originating from South-West Asia. It has been largely studied in Europe and on several remote islands, but the genetic structure and invasion history of this taxon have been little investigated in several continental areas, including West Africa. In this study, we focussed on invasive populations of M. m. domesticus in Senegal. In this focal area for European settlers, the distribution area and invasion spread of the house mouse is documented by decades of data on commensal rodent communities. Genetic variation at one mitochondrial locus and 16 nuclear microsatellite markers was analysed from individuals sampled in 36 sites distributed across the country. A combination of phylogeographic and population genetics methods showed that there was a single introduction event on the northern coast of Senegal, from an exogenous (probably West European) source, followed by a secondary introduction from northern Senegal into a coastal site further south. The geographic locations of these introduction sites were consistent with the colonial history of Senegal. Overall, the marked microsatellite genetic structure observed in Senegal, even between sites located close together, revealed a complex interplay of different demographic processes occurring during house mouse spatial expansion, including sequential founder effects and stratified dispersal due to human transport along major roads.

Ancient DNA and the rewriting of human history: be sparing with Occam's razor.

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Haber, Marc; Mezzavilla, Massimo; Xue, Yali; Tyler-Smith, Chris

2016-01-11

Ancient DNA research is revealing a human history far more complex than that inferred from parsimonious models based on modern DNA. Here, we review some of the key events in the peopling of the world in the light of the findings of work on ancient DNA.

Demographic crisis and recovery: a case study of the Xavante of Pimentel Barbosa.

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Flowers, N

1994-03-01

This case study of the Xavante of Pimentel Barbosa is an example of an Amazonian Indian group that, when exposed to White society, experienced the common history of diseases and social disruption, and then eventually, recovered from the demographic shock, increased fertility, and reduced mortality. Early contact for the Xavante was during the early 18th century in Goias state, Brazil; by the end of the 19th century the Xavante had migrated west into Mato Grosso in isolation. Brazilian government interests (1940s) and a research expeditionary group (1962) resulted in health posts and extensive genetic, epidemiologic, and demographic studies. The results showed good physical and nutritional status, but stress from epidemic disease and social disruption. Conditions had improved by 1976, and the battle was with encroaching ranchers. Strong indian political action led to the securing of boundaries within the Pimentel Barbosa reservation by 1977. The population doubled from 249 in 1977 to 411 in 1988, and increased to 3 villages. There was evidence of a return to more traditional practices. Data collection for this analysis occurred during 1976-77 and 1988 and 1990. Results were provided for recent demographic change, recent births and deaths, factors affecting fertility, fertility change, parity and infant mortality, life expectancy changes, infanticide, population growth, marriage patterns, and health changes. Fertility histories were collected from 71 women in 1971 and 109 women in 1990. Difficulties were encountered due to Xavante differences in enumeration of children. In the comparison of the surveys in 1977 and 1990, there was close correspondence of reported births, and discrepancies of 4-9 births and in age at death. The difficulties encountered were attributed to problems with interpreters. The demographic analysis showed evidence of introduced diseases, which increased infant mortality and threatened population replacement, followed by decreased infant

Neutral Theory: From Complex Population History to Natural Selection and Sociocultural Phenomena in Human Populations.

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Austerlitz, Frédéric; Heyer, Evelyne

2018-06-01

Here, we present a synthetic view on how Kimura's Neutral theory has helped us gaining insight on the different evolutionary forces that shape human evolution. We put this perspective in the frame of recent emerging challenges: the use of whole genome data for reconstructing population histories, natural selection on complex polygenic traits, and integrating cultural processes in human evolution.

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

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Pennarun Erwan

2012-12-01

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

Composite likelihood estimation of demographic parameters

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Garrigan Daniel

2009-11-01

Full Text Available Abstract Background Most existing likelihood-based methods for fitting historical demographic models to DNA sequence polymorphism data to do not scale feasibly up to the level of whole-genome data sets. Computational economies can be achieved by incorporating two forms of pseudo-likelihood: composite and approximate likelihood methods. Composite likelihood enables scaling up to large data sets because it takes the product of marginal likelihoods as an estimator of the likelihood of the complete data set. This approach is especially useful when a large number of genomic regions constitutes the data set. Additionally, approximate likelihood methods can reduce the dimensionality of the data by summarizing the information in the original data by either a sufficient statistic, or a set of statistics. Both composite and approximate likelihood methods hold promise for analyzing large data sets or for use in situations where the underlying demographic model is complex and has many parameters. This paper considers a simple demographic model of allopatric divergence between two populations, in which one of the population is hypothesized to have experienced a founder event, or population bottleneck. A large resequencing data set from human populations is summarized by the joint frequency spectrum, which is a matrix of the genomic frequency spectrum of derived base frequencies in two populations. A Bayesian Metropolis-coupled Markov chain Monte Carlo (MCMCMC method for parameter estimation is developed that uses both composite and likelihood methods and is applied to the three different pairwise combinations of the human population resequence data. The accuracy of the method is also tested on data sets sampled from a simulated population model with known parameters. Results The Bayesian MCMCMC method also estimates the ratio of effective population size for the X chromosome versus that of the autosomes. The method is shown to estimate, with reasonable

Inferring the demographic history of European Ficedula flycatcher populations

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Backström Niclas

2013-01-01

Full Text Available Abstract Background Inference of population and species histories and population stratification using genetic data is important for discriminating between different speciation scenarios and for correct interpretation of genome scans for signs of adaptive evolution and trait association. Here we use data from 24 intronic loci re-sequenced in population samples of two closely related species, the pied flycatcher and the collared flycatcher. Results We applied Isolation-Migration models, assignment analyses and estimated the genetic differentiation and diversity between species and between populations within species. The data indicate a divergence time between the species of Conclusions Our results provide further evidence for a divergence process where different genomic regions may be at different stages of speciation. We also conclude that forthcoming analyses of genotype-phenotype relations in these ecological model species should be designed to take population stratification into account.

Political demography: Powerful trends under-attended by demographic science.

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Teitelbaum, Michael S

2015-01-01

The interconnections between politics and the dramatic demographic changes under way around the world have been neglected by the two research disciplines that could contribute most to their understanding: demography and political science. Instead, this area of 'political demography' has largely been ceded to political activists, pundits, and journalists, leading often to exaggerated or garbled interpretation. The terrain includes some of the most politically sensitive and contested issues: alleged demographically determined shifts in the international balance of power; low fertility, population decline, and demographic ageing; international migration; change in national identity; and compositional shifts in politically sensitive social categories and human rights. Meanwhile many governments and non-governmental actors have actively pursued varieties of 'strategic demography', deploying fertility, mortality, or migration as instruments of domestic or international policy. Political scientists and demographers could and should use their knowledge and analytic techniques to improve understanding and to moderate excessive claims and fears on these topics.

Oromandibular Dystonia: Demographics and Clinical Data from 240 Patients

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Linda Slaim

2018-05-01

Full Text Available Objective To report demographic data from a large cohort of patients with oromandibular dystonia (OMD. Methods This is a retrospective review of patients with OMD referred to our institution between 1989 and 2015. Demographic (age of onset, gender, and familial history of dystonia and clinical (type of OMD, associated dystonia, and etiology of dystonia data were collected from a cohort of 240 individuals. Results The mean age of onset of OMD was 51.6 years old, with a female predominance (2:1. A family history of dystonia was found in 6 patients (2.5%. One hundred and forty-nine patients (62.1% had the jaw-opening type of OMD, 48 patients (20.0% had the jaw-closing type, and 43 patients (17.9% had a mixed form of OMD. Lingual dystonia was also present in 64 (26.7% of these patients. Eighty-two patients (34.2% had a focal dystonia, 131 patients (54.6% had a segmental dystonia, and 27 patients (11.3% had a generalized dystonia. One hundred and seventy-one patients (71.3% had idiopathic OMD. Conclusion OMD is a chronic and disabling focal dystonia. Our study found a prevalence of female patients, an onset in middle age and a predominantly idiopathic etiology. Unlike other studies, jaw-opening was found to be the most frequent clinical type of OMD.

Population-specific life histories contribute to metapopulation viability

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Halsey, Samniqueka J.; Bell, Timothy J.; McEachern, A. Kathryn; Pavlovic, Noel B.

2016-01-01

Restoration efforts can be improved by understanding how variations in life-history traits occur within populations of the same species living in different environments. This can be done by first understanding the demographic responses of natural occurring populations. Population viability analysis continues to be useful to species management and conservation with sensitivity analysis aiding in the understanding of population dynamics. In this study, using life-table response experiments and elasticity analyses, we investigated how population-specific life-history demographic responses contributed to the metapopulation viability of the Federally threatened Pitcher's thistle (Cirsium pitcheri). Specifically, we tested the following hypotheses: (1) Subpopulations occupying different environments within a metapopulation have independent demographic responses and (2) advancing succession results in a shift from a demographic response focused on growth and fecundity to one dominated by stasis. Our results showed that reintroductions had a positive contribution to the metapopulation growth rate as compared to native populations which had a negative contribution. We found no difference in succession on the contribution to metapopulation viability. In addition, we identified distinct population-specific contributions to metapopulation viability and were able to associate specific life-history demographic responses. For example, the positive impact of Miller High Dunes population on the metapopulation growth rate resulted from high growth contributions, whereas increased time of plant in stasis for the State Park Big Blowout population resulted in negative contributions. A greater understanding of how separate populations respond in their corresponding environment may ultimately lead to more effective management strategies aimed at reducing extinction risk. We propose the continued use of sensitivity analyses to evaluate population-specific demographic influences on

A history in-care predicts unique characteristics in a homeless population with mental illness.

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Roos, Leslie E; Distasio, Jino; Bolton, Shay-Lee; Katz, Laurence Y; Afifi, Tracie O; Isaak, Corinne; Goering, Paula; Bruce, Lucille; Sareen, Jitender

2014-10-01

Multiple studies of homeless persons report an increased prevalence of a history in-care, but there is a dearth of information on associated outcomes or relevant demographic profiles. This information is critical to understanding if certain individuals are at elevated risk or might benefit from specific intervention. Here, we investigate how a history in-care relates to demographics and multiple outcome measures in a homeless population with mental illness. Using the Mini International Neuropsychiatric Interview (MINI), the Short-Form 12, and a trauma questionnaire, we investigated baseline differences in demographics and length of homelessness in the At Home/Chez Soi Trial (N=504) Winnipeg homeless population with and without a history in-care. Approximately 50% of the homeless sample reported a history in-care. This group was significantly more likely to be young, female, married or cohabitating, of Aboriginal heritage, have less education, and have longer lifetime homelessness. Individuals of Aboriginal heritage with a history in-care were significantly more likely to report a familial history of residential school. Individuals with a history in-care experienced different prevalence rates of Axis 1 mental disorders. Those with a history in-care also reported significantly more traumatic events (particularly interpersonal). A distinctive high-risk profile emerged for individuals with a history in-care. Sociocultural factors of colonization and intergenerational transmission of trauma appear to be particularly relevant in the trajectories for individuals of Aboriginal heritage. Given the high prevalence of a history in-care, interventions and policy should reflect the specific vulnerability of this population, particularly in regards to trauma-informed services. Copyright © 2013 Elsevier Ltd. All rights reserved.

Demographic monitoring of wild muriqui populations: Criteria for defining priority areas and monitoring intensity.

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Strier, Karen B; Possamai, Carla B; Tabacow, Fernanda P; Pissinatti, Alcides; Lanna, Andre M; Rodrigues de Melo, Fabiano; Moreira, Leandro; Talebi, Maurício; Breves, Paula; Mendes, Sérgio L; Jerusalinsky, Leandro

2017-01-01

Demographic data are essential to assessments of the status of endangered species. However, establishing an integrated monitoring program to obtain useful data on contemporary and future population trends requires both the identification of priority areas and populations and realistic evaluations of the kinds of data that can be obtained under different monitoring regimes. We analyzed all known populations of a critically endangered primate, the muriqui (genus: Brachyteles) using population size, genetic uniqueness, geographic importance (including potential importance in corridor programs) and implementability scores to define monitoring priorities. Our analyses revealed nine priority populations for the northern muriqui (B. hypoxanthus) and nine for the southern muriqui (B. arachnoides). In addition, we employed knowledge of muriqui developmental and life history characteristics to define the minimum monitoring intensity needed to evaluate demographic trends along a continuum ranging from simple descriptive changes in population size to predictions of population changes derived from individual based life histories. Our study, stimulated by the Brazilian government's National Action Plan for the Conservation of Muriquis, is fundamental to meeting the conservation goals for this genus, and also provides a model for defining priorities and methods for the implementation of integrated demographic monitoring programs for other endangered and critically endangered species of primates.

Demographic monitoring of wild muriqui populations: Criteria for defining priority areas and monitoring intensity.

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Karen B Strier

Full Text Available Demographic data are essential to assessments of the status of endangered species. However, establishing an integrated monitoring program to obtain useful data on contemporary and future population trends requires both the identification of priority areas and populations and realistic evaluations of the kinds of data that can be obtained under different monitoring regimes. We analyzed all known populations of a critically endangered primate, the muriqui (genus: Brachyteles using population size, genetic uniqueness, geographic importance (including potential importance in corridor programs and implementability scores to define monitoring priorities. Our analyses revealed nine priority populations for the northern muriqui (B. hypoxanthus and nine for the southern muriqui (B. arachnoides. In addition, we employed knowledge of muriqui developmental and life history characteristics to define the minimum monitoring intensity needed to evaluate demographic trends along a continuum ranging from simple descriptive changes in population size to predictions of population changes derived from individual based life histories. Our study, stimulated by the Brazilian government's National Action Plan for the Conservation of Muriquis, is fundamental to meeting the conservation goals for this genus, and also provides a model for defining priorities and methods for the implementation of integrated demographic monitoring programs for other endangered and critically endangered species of primates.

The atom in human thought history

International Nuclear Information System (INIS)

Pullman, B.

1995-01-01

This book speaks of atom history. From the ancient Greece until now, science debated around the question for or against the atom conception of universe. In this book of sciences history, the author goes over the major events of this intellectual joust with a real pedagogic care, from Democrite, Aristote, Platon to Planck, Bohr, Einstein, Schroedinger and some others

Linking habitat structure to life history strategy: Insights from a Mediterranean killifish

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Cavraro, Francesco; Daouti, Irini; Leonardos, Ioannis; Torricelli, Patrizia; Malavasi, Stefano

2014-01-01

Modern theories of life history evolution deal with finding links between environmental factors, demographic structure of animal populations and the optimal life history strategy. Small-sized teleost fish, occurring in fragmented populations under contrasting environments, have been widely used as study models to investigate these issues. In the present study, the Mediterranean killifish Aphanius fasciatus was used to investigate the relationships between some habitat features and life history strategy. We selected four sites in the Venice lagoon inhabited by this species, exhibiting different combinations of two factors: overall adult mortality, related to intertidal water coverage and a consequent higher level of predator exposure, and the level of sediment organic matter, as indicator of habitat trophic richness. Results showed that these were the two most important factors influencing demography and life history traits in the four sites. Fish from salt marshes with high predator pressure were smaller and produced a higher number of eggs, whereas bigger fish and a lower reproductive investment were found in the two closed, not tidally influenced habitats. Habitat richness was positively related with population density, but negatively related with growth rate. In particular the synergy between high resources and low predation level was found to be important in shaping peculiar life history traits. Results were discussed in the light of the interactions between selective demographic forces acting differentially on age/size classes, such as predation, and habitat trophic richness that may represent an important energetic constraint on life history traits. The importance to link habitat productivity and morphology to demographic factors for a better understanding of the evolution of life history strategy under contrasting environments was finally suggested.

Validity of self-reported periodontal measures, demographic characteristics and systemic medical conditions.

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Chatzopoulos, Georgios S; Cisneros, Alejandro; Sanchez, Miguel; Lunos, Scott; Wolff, Larry F

2018-04-06

The objective of the present study was to assess self-reported periodontal screening questions, demographic characteristics, systemic medical conditions and tobacco use for predicting periodontal disease among individuals seeking dental therapy in a university dental clinic. In this retrospective study, a total of 4,890 randomly selected dental charts were evaluated from among patients who had attended the University of Minnesota School of Dentistry clinics for treatment. Radiographic bone loss measurements were utilized to assess the severity of periodontal disease. Demographic characteristics as well as medical history of the patients were also recorded. Five self-reported periodontal screening questions were included with the range of answers limited to Yes/No. Generalized logit models were used to assess the association between bone loss and the predictors. The sample mean age was 54.1 years and included 52.6% males and 14.9% smokers with a mean number of missing teeth of 3.5. Self-reported tooth mobility, history of "gum treatment" and the importance to keep the teeth as well as age, tobacco use and cancer were statistically significant (p brushing", gender, diabetes, anxiety and arthritis. Self-reported periodontal screening questions as well as demographic characteristics, smoking and systemic medical conditions were significant predictors of periodontal disease and they could be used as valid, economical and practical measures. This article is protected by copyright. All rights reserved. © 2018 American Academy of Periodontology.

Life history and demographic drivers of reservoir competence for three tick-borne zoonotic pathogens.

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Richard S Ostfeld

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

Is the demographic dividend an education dividend?

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

2014-02-01

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.

Towards Household History

NARCIS (Netherlands)

van Rappard, J.F.H.

1998-01-01

It is maintained that in contradistinction to the natural sciences, in psychology (and other human sciences) ‘history is not past tense’. This is borne out by the contemporary relevance of a specific part of the history of psychology, which focuses on the internal-theoretical significance of history

Long livestock farming history and human landscape shaping revealed by lake sediment DNA.

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Giguet-Covex, Charline; Pansu, Johan; Arnaud, Fabien; Rey, Pierre-Jérôme; Griggo, Christophe; Gielly, Ludovic; Domaizon, Isabelle; Coissac, Eric; David, Fernand; Choler, Philippe; Poulenard, Jérôme; Taberlet, Pierre

2014-01-01

The reconstruction of human-driven, Earth-shaping dynamics is important for understanding past human/environment interactions and for helping human societies that currently face global changes. However, it is often challenging to distinguish the effects of the climate from human activities on environmental changes. Here we evaluate an approach based on DNA metabarcoding used on lake sediments to provide the first high-resolution reconstruction of plant cover and livestock farming history since the Neolithic Period. By comparing these data with a previous reconstruction of erosive event frequency, we show that the most intense erosion period was caused by deforestation and overgrazing by sheep and cowherds during the Late Iron Age and Roman Period. Tracking plants and domestic mammals using lake sediment DNA (lake sedDNA) is a new, promising method for tracing past human practices, and it provides a new outlook of the effects of anthropogenic factors on landscape-scale changes.

Genetic demographic networks: Mathematical model and applications.

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Kimmel, Marek; Wojdyła, Tomasz

2016-10-01

Recent improvement in the quality of genetic data obtained from extinct human populations and their ancestors encourages searching for answers to basic questions regarding human population history. The most common and successful are model-based approaches, in which genetic data are compared to the data obtained from the assumed demography model. Using such approach, it is possible to either validate or adjust assumed demography. Model fit to data can be obtained based on reverse-time coalescent simulations or forward-time simulations. In this paper we introduce a computational method based on mathematical equation that allows obtaining joint distributions of pairs of individuals under a specified demography model, each of them characterized by a genetic variant at a chosen locus. The two individuals are randomly sampled from either the same or two different populations. The model assumes three types of demographic events (split, merge and migration). Populations evolve according to the time-continuous Moran model with drift and Markov-process mutation. This latter process is described by the Lyapunov-type equation introduced by O'Brien and generalized in our previous works. Application of this equation constitutes an original contribution. In the result section of the paper we present sample applications of our model to both simulated and literature-based demographies. Among other we include a study of the Slavs-Balts-Finns genetic relationship, in which we model split and migrations between the Balts and Slavs. We also include another example that involves the migration rates between farmers and hunters-gatherers, based on modern and ancient DNA samples. This latter process was previously studied using coalescent simulations. Our results are in general agreement with the previous method, which provides validation of our approach. Although our model is not an alternative to simulation methods in the practical sense, it provides an algorithm to compute pairwise

Human migration patterns in Yemen and implications for reconstructing prehistoric population movements.

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Aida T Miró-Herrans

Full Text Available Population migration has played an important role in human evolutionary history and in the patterning of human genetic variation. A deeper and empirically-based understanding of human migration dynamics is needed in order to interpret genetic and archaeological evidence and to accurately reconstruct the prehistoric processes that comprise human evolutionary history. Current empirical estimates of migration include either short time frames (i.e. within one generation or partial knowledge about migration, such as proportion of migrants or distance of migration. An analysis of migration that includes both proportion of migrants and distance, and direction over multiple generations would better inform prehistoric reconstructions. To evaluate human migration, we use GPS coordinates from the place of residence of the Yemeni individuals sampled in our study, their birthplaces and their parents' and grandparents' birthplaces to calculate the proportion of migrants, as well as the distance and direction of migration events between each generation. We test for differences in these values between the generations and identify factors that influence the probability of migration. Our results show that the proportion and distance of migration between females and males is similar within generations. In contrast, the proportion and distance of migration is significantly lower in the grandparents' generation, most likely reflecting the decreasing effect of technology. Based on our results, we calculate the proportion of migration events (0.102 and mean and median distances of migration (96 km and 26 km for the grandparent's generation to represent early times in human evolution. These estimates can serve to set parameter values of demographic models in model-based methods of prehistoric reconstruction, such as approximate Bayesian computation. Our study provides the first empirically-based estimates of human migration over multiple generations in a developing

Evaluating Failures and near Misses in Human Spaceflight History for Lessons for Future Human Spaceflight

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Barr, Stephanie

2010-01-01

Studies done in the past have drawn on lessons learned with regard to human loss-of-life events. However, an examination of near-fatal accidents can be equally useful, not only in detecting causes, both proximate and systemic, but also for determining what factors averted disaster, what design decisions and/or operator actions prevented catastrophe. Binary pass/fail launch history is often used for risk, but this also has limitations. A program with a number of near misses can look more reliable than a consistently healthy program with a single out-of-family failure. Augmenting reliability evaluations with this near miss data can provide insight and expand on the limitations of a strictly pass/fail evaluation. This paper intends to show how near-miss lessons learned can provide crucial data for any new human spaceflight programs that are interested in sending man into space

Demographic and ecological risk factors for human influenza A virus infections in rural Indonesia.

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Root, Elisabeth Dowling; Agustian, Dwi; Kartasasmita, Cissy; Uyeki, Timothy M; Simões, Eric A F

2017-09-01

Indonesia has the world's highest reported mortality for human infections with highly pathogenic avian influenza (HPAI) A(H5N1) virus. Indonesia is an agriculturally driven country where human-animal mixing is common and provides a unique environment for zoonotic influenza A virus transmission. To identify potential demographic and ecological risk factors for human infection with seasonal influenza A viruses in rural Indonesia, a population-based study was conducted in Cileunyi and Soreang subdistricts near Bandung in western Java from 2008 to 2011. Passive influenza surveillance with RT-PCR confirmation of influenza A viral RNA in respiratory specimens was utilized for case ascertainment. A population census and mapping were utilized for population data collection. The presence of influenza A(H3N2) and A(H1N1)pdm09 virus infections in a household was modeled using Generalized Estimating Equations. Each additional child aged <5 years in a household increased the odds of H3N2 approximately 5 times (OR=4.59, 95%CI: 3.30-6.24) and H1N1pdm09 by 3.5 times (OR=3.53, 95%CI: 2.51-4.96). In addition, the presence of 16-30 birds in the house was associated with an increased odds of H3N2 (OR=5.08, 95%CI: 2.00-12.92) and H1N1pdm09 (OR=12.51 95%CI: 6.23-25.13). Our findings suggest an increase in influenza A virus infections in rural Indonesian households with young children and poultry. © 2017 The Authors. Influenza and Other Respiratory Viruses Published by John Wiley & Sons Ltd.

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

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

2006-04-01

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

Holocene river history of the Danube: human-environment interactions on its islands in Hungary

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Viczián, István; Balogh, János; Kis, Éva; Szeberényi, József

2016-04-01

A change in the frequency and magnitude of floods is the main response of river systems to climatic change. Natural floods are highly sensitive to even modest changes of climate. The discharge and the characteristics of floods basically determine the floodplain evolution and the feasibility of human land use and inhabitation on the islands and floodplains. The study revealed that those small islands of large rivers which have the surface rising only some meters above the river are particularly suitable research objects of Holocene climate variability as they are exposed to floods, react sensitively to environmental changes and their evolution may be paralleled with human history. The research area covers the islands of the Danube along the river between Komárom and Paks in Hungary, which is about 250 km, includes more than 50 smaller or formerly existing islands and two extensive islands: the Szentendre Island and Csepel Island. Data gathered from 570 archaeological sites of those islands from Neolithic to Modern Ages were analysed and interpreted in accordance with climate history and floodplain evolution. Nevertheless, the study is not only about river and its environmental history but it demonstrates the role of river and climatic variability in the history of mankind. The environment of the floodplain, the river hydrology, the sedimentation, the formation of islands and the incision and aggradation of surrounding riverbeds, the frequency of devastating floods have significantly changed through the historical time periods, which is reflected in the number and locations of archaeological sites on the islands. Their occupation history reflects the changes in discharge, climate, geomorphology, floods and human impacts and indicates historical periods with low or high probability of inundation. The most favourable periods for an island's occupation concerning the flood risk of its surfaces - and consequently of the banks along the river - are the first parts of a

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

NARCIS (Netherlands)

Herfindal, Ivar; van de Pol, Martijn; Nielsen, Jan Tøttrup; Sæther, Bernt-Erik; Møller, Anders Pape

2015-01-01

1.Environmental variation can induce life history changes that can last over a large part of the lifetime of an organism. If multiple demographic traits are affected, expected changes in climate may influence environmental covariances among traits in a complex manner. Thus, examining the

Structural History of Human SRGAP2 Proteins.

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Sporny, Michael; Guez-Haddad, Julia; Kreusch, Annett; Shakartzi, Sivan; Neznansky, Avi; Cross, Alice; Isupov, Michail N; Qualmann, Britta; Kessels, Michael M; Opatowsky, Yarden

2017-06-01

In the development of the human brain, human-specific genes are considered to play key roles, conferring its unique advantages and vulnerabilities. At the time of Homo lineage divergence from Australopithecus, SRGAP2C gradually emerged through a process of serial duplications and mutagenesis from ancestral SRGAP2A (3.4-2.4 Ma). Remarkably, ectopic expression of SRGAP2C endows cultured mouse brain cells, with human-like characteristics, specifically, increased dendritic spine length and density. To understand the molecular mechanisms underlying this change in neuronal morphology, we determined the structure of SRGAP2A and studied the interplay between SRGAP2A and SRGAP2C. We found that: 1) SRGAP2A homo-dimerizes through a large interface that includes an F-BAR domain, a newly identified F-BAR extension (Fx), and RhoGAP-SH3 domains. 2) SRGAP2A has an unusual inverse geometry, enabling associations with lamellipodia and dendritic spine heads in vivo, and scaffolding of membrane protrusions in cell culture. 3) As a result of the initial partial duplication event (∼3.4 Ma), SRGAP2C carries a defective Fx-domain that severely compromises its solubility and membrane-scaffolding ability. Consistently, SRGAP2A:SRAGP2C hetero-dimers form, but are insoluble, inhibiting SRGAP2A activity. 4) Inactivation of SRGAP2A is sensitive to the level of hetero-dimerization with SRGAP2C. 5) The primal form of SRGAP2C (P-SRGAP2C, existing between ∼3.4 and 2.4 Ma) is less effective in hetero-dimerizing with SRGAP2A than the modern SRGAP2C, which carries several substitutions (from ∼2.4 Ma). Thus, the genetic mutagenesis phase contributed to modulation of SRGAP2A's inhibition of neuronal expansion, by introducing and improving the formation of inactive SRGAP2A:SRGAP2C hetero-dimers, indicating a stepwise involvement of SRGAP2C in human evolutionary history. © The Author 2017. Published by Oxford University Press on behalf of the Society for Molecular Biology and Evolution.

Virtual impact: visualizing the potential effects of cosmic impact in human history

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Masse, W Bruce [Los Alamos National Laboratory; Janecky, David R [Los Alamos National Laboratory; Forte, Maurizio [UC MERCED; Barrientos, Gustavo [UNIV OF LA PLATA, ARG.

2009-01-01

Current models indicate that catastrophic impacts by asteroids and comets capable of killing more than one quarter of Earth's human population have occurred on average once every million years; smaller impacts, such the 1908 Tunguska impact that leveled more than 2,000 square km of Siberian forest, occur every 200-300 years. Therefore, cosmic impact likely significantly affected hominine evolution and conceivably played a role in Holocene period human culture history. Regrettably, few archaeologists are trained to appreciate the nature and potential effects of cosmic impact. We have developed a conceptual model for an extensible set of educational and research tools based on virtual reality collaborative environments to engage archaeologists and the general public on the topic of the role of cosmic impact in human history. Our initial focus is on two documented asteroid impacts in Argentina during the period of 4000 to 1000 B.C. Campo del Cicio resulted in an energy release of around 2-3 megatons (100-150 times the Hiroshima atomic weapon), and left several craters and a strewn field covering 493 km{sup 2} in northeastern Argentina. Rio Cuarto was likely more than 1000 megatons and may have devastated an area greater than 50,000 km{sup 2} in central Argentina. We are focusing on reconstructions of these events and their potential effects on contemporary hunter and gatherers. Our vinual reality tools also introduce interactive variables (e.g., impactor physical properties, climate, vegetation, topography, and social complexity) to allow researchers and students to better investigate and evaluate the factors that significantly influence cosmic impact effects.

Jewish history as a history of immigration: an overview of current historiography in the Scandinavian countries

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Christhard Hoffmann

2016-01-01

Full Text Available This article provides a first critical overview of the historiography of Jewish immigration and integration in Sweden, Denmark and Norway. While the experience of immigration has been crucial for Scandinavian Jewry, scholarly interest in Jewish migration history only emerged during the 1980s in connection with the focus on migration and ethnicity in Swedish research and the adaptation of sociological concepts of migration in general historiography. By analysing key historio-graphical works, focusing on their approaches and main narratives, this article aims at a critical methodological self-reflection. It identifies two major approaches to Jewish immigration history in current Scandinavian historiography: the demographic and social history approach, focusing in particular on the role of Jewish immigrants in the labour market, their settlement and housing conditions and their social mobility; and the cultural history approach, reconstructing and preserving the vanished world of Yiddish immigrant culture.

Digest: Demographic inferences accounting for selection at linked sites†.

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Simon, Alexis; Duranton, Maud

2018-05-16

Complex demography and selection at linked sites can generate spurious signatures of divergent selection. Unfortunately, many attempts at demographic inference consider overly simple models and neglect the effect of selection at linked sites. In this issue, Rougemont and Bernatchez (2018) applied an approximate Bayesian computation (ABC) framework that accounts for indirect selection to reveal a complex history of secondary contacts in Atlantic salmon (Salmo salar) that might explain a high rate of latitudinal clines in this species. © 2018 The Author(s). Evolution © 2018 The Society for the Study of Evolution.

Future Scenarios of Land Change Based on Empirical Data and Demographic Trends

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Sleeter, Benjamin M.; Wilson, Tamara S.; Sharygin, Ethan; Sherba, Jason T.

2017-11-01

Changes in land use and land cover (LULC) have important and fundamental interactions with the global climate system. Top-down global scale projections of land use change have been an important component of climate change research; however, their utility at local to regional scales is often limited. The goal of this study was to develop an approach for projecting changes in LULC based on land use histories and demographic trends. We developed a set of stochastic, empirical-based projections of LULC change for the state of California, for the period 2001-2100. Land use histories and demographic trends were used to project a "business-as-usual" (BAU) scenario and three population growth scenarios. For the BAU scenario, we projected developed lands would more than double by 2100. When combined with cultivated areas, we projected a 28% increase in anthropogenic land use by 2100. As a result, natural lands were projected to decline at a rate of 139 km2 yr-1; grasslands experienced the largest net decline, followed by shrublands and forests. The amount of cultivated land was projected to decline by approximately 10%; however, the relatively modest change masked large shifts between annual and perennial crop types. Under the three population scenarios, developed lands were projected to increase 40-90% by 2100. Our results suggest that when compared to the BAU projection, scenarios based on demographic trends may underestimate future changes in LULC. Furthermore, regardless of scenario, the spatial pattern of LULC change was likely to have the greatest negative impacts on rangeland ecosystems.

Future scenarios of land change based on empirical data and demographic trends

Science.gov (United States)

Sleeter, Benjamin M.; Wilson, Tamara; Sharygin, Ethan; Sherba, Jason

2017-01-01

Changes in land use and land cover (LULC) have important and fundamental interactions with the global climate system. Top-down global scale projections of land use change have been an important component of climate change research; however, their utility at local to regional scales is often limited. The goal of this study was to develop an approach for projecting changes in LULC based on land use histories and demographic trends. We developed a set of stochastic, empirical-based projections of LULC change for the state of California, for the period 2001–2100. Land use histories and demographic trends were used to project a “business-as-usual” (BAU) scenario and three population growth scenarios. For the BAU scenario, we projected developed lands would more than double by 2100. When combined with cultivated areas, we projected a 28% increase in anthropogenic land use by 2100. As a result, natural lands were projected to decline at a rate of 139 km2 yr−1; grasslands experienced the largest net decline, followed by shrublands and forests. The amount of cultivated land was projected to decline by approximately 10%; however, the relatively modest change masked large shifts between annual and perennial crop types. Under the three population scenarios, developed lands were projected to increase 40–90% by 2100. Our results suggest that when compared to the BAU projection, scenarios based on demographic trends may underestimate future changes in LULC. Furthermore, regardless of scenario, the spatial pattern of LULC change was likely to have the greatest negative impacts on rangeland ecosystems.

Human Metapneumovirus Infection is Associated with Severe Respiratory Disease in Preschool Children with History of Prematurity.

Science.gov (United States)

Pancham, Krishna; Sami, Iman; Perez, Geovanny F; Huseni, Shehlanoor; Kurdi, Bassem; Rose, Mary C; Rodriguez-Martinez, Carlos E; Nino, Gustavo

2016-02-01

Human metapneumovirus (HMPV) is a recently discovered respiratory pathogen of the family Paramyxoviridae, the same family as that of respiratory syncytial virus (RSV). Premature children are at high risk of severe RSV infections, however, it is unclear whether HMPV infection is more severe in hospitalized children with a history of severe prematurity. We conducted a retrospective analysis of the clinical respiratory presentation of all polymerase chain reaction-confirmed HMPV infections in preschool-age children (≤5 years) with and without history of severe prematurity (prematurity. Preschool children with a history of prematurity had more severe HMPV disease as illustrated by longer hospitalizations, new or increased need for supplemental O2, and higher severity scores independently of age, ethnicity, and history of asthma. Our study suggests that HMPV infection causes significant disease burden among preschool children with a history of prematurity leading to severe respiratory infections and increasing health care resource utilization due to prolonged hospitalizations. Copyright © 2016. Published by Elsevier B.V.

Modeling Relationships Between Flight Crew Demographics and Perceptions of Interval Management

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Remy, Benjamin; Wilson, Sara R.

2016-01-01

The Interval Management Alternative Clearances (IMAC) human-in-the-loop simulation experiment was conducted to assess interval management system performance and participants' acceptability and workload while performing three interval management clearance types. Twenty-four subject pilots and eight subject controllers flew ten high-density arrival scenarios into Denver International Airport during two weeks of data collection. This analysis examined the possible relationships between subject pilot demographics on reported perceptions of interval management in IMAC. Multiple linear regression models were created with a new software tool to predict subject pilot questionnaire item responses from demographic information. General patterns were noted across models that may indicate flight crew demographics influence perceptions of interval management.

Danto, history, and the tragedy of human existence

NARCIS (Netherlands)

Ankersmit, FR

2003-01-01

Philosophy of history is the Cinderella of contemporary philosophy. Philosophers rarely believe that the issues dealt with by philosophers of history are matters of any great theoretical interest or urgency. In their view philosophy of history rarely goes beyond the question of how results that have

The Impact of the Universal Declaration of Human Rights on the Study of History

NARCIS (Netherlands)

De Baets, Antoon

There is perhaps no text with a broader impact on our lives than the 1948 Universal Declaration of Human Rights (UDHR). It is strange, therefore, that historians have paid so little attention to the UDHR. I argue that its potential impact on the study of history is profound. After asking whether the

A review of small canned computer programs for survey research and demographic analysis.

Science.gov (United States)

Sinquefield, J C

1976-12-01

A variety of small canned computer programs for survey research and demographic analysis appropriate for use in developing countries are reviewed in this article. The programs discussed are SPSS (Statistical Package for the Social Sciences); CENTS, CO-CENTS, CENTS-AID, CENTS-AIE II; MINI-TAB EDIT, FREQUENCIES, TABLES, REGRESSION, CLIENT RECORD, DATES, MULT, LIFE, and PREGNANCY HISTORY; FIVFIV and SINSIN; DCL (Demographic Computer Library); MINI-TAB Population Projection, Functional Population Projection, and Family Planning Target Projection. A description and evaluation for each program of uses, instruction manuals, computer requirements, and procedures for obtaining manuals and programs are provided. Such information is intended to facilitate and encourage the use of the computer by data processors in developing countries.

Early life history and habitat ecology of estuarine fishes: responses to natural and human induced change

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Kenneth Able

2015-12-01

Full Text Available Our understanding of the early life history of fishes and their habitats has proceeded from basic natural history to ecology, but we often need to return to natural history to address deficiencies in conceptual and quantitative models of ecosystems. This understanding is further limited by the complex life history of fishes and the lack of appreciation of shifting baselines in estuaries. These inadequacies are especially evident when we try to address the effects of human influences, e.g. fishing, urbanization, and climate change. Often our baselines are inadequate or inaccurate. Our work has detected these along the coasts of the U.S. in extensive time series of larval fish ingress into estuaries, studies of the effects of urbanization, and responses to catastrophes such as the BP oil spill. Long-term monitoring, especially, continues to provide critical insights

Genetic variability, local selection and demographic history: genomic evidence of evolving towards allopatric speciation in Asian seabass.

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Wang, Le; Wan, Zi Yi; Lim, Huan Sein; Yue, Gen Hua

2016-08-01

Genomewide analysis of genetic divergence is critically important in understanding the genetic processes of allopatric speciation. We sequenced RAD tags of 131 Asian seabass individuals of six populations from South-East Asia and Australia/Papua New Guinea. Using 32 433 SNPs, we examined the genetic diversity and patterns of population differentiation across all the populations. We found significant evidence of genetic heterogeneity between South-East Asian and Australian/Papua New Guinean populations. The Australian/Papua New Guinean populations showed a rather lower level of genetic diversity. FST and principal components analysis revealed striking divergence between South-East Asian and Australian/Papua New Guinean populations. Interestingly, no evidence of contemporary gene flow was observed. The demographic history was further tested based on the folded joint site frequency spectrum. The scenario of ancient migration with historical population size changes was suggested to be the best fit model to explain the genetic divergence of Asian seabass between South-East Asia and Australia/Papua New Guinea. This scenario also revealed that Australian/Papua New Guinean populations were founded by ancestors from South-East Asia during mid-Pleistocene and were completely isolated from the ancestral population after the last glacial retreat. We also detected footprints of local selection, which might be related to differential ecological adaptation. The ancient gene flow was examined and deemed likely insufficient to counteract the genetic differentiation caused by genetic drift. The observed genomic pattern of divergence conflicted with the 'genomic islands' scenario. Altogether, Asian seabass have likely been evolving towards allopatric speciation since the split from the ancestral population during mid-Pleistocene. © 2016 John Wiley & Sons Ltd.

The history of human cytogenetics in India-A review.

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Dutta, Usha R

2016-09-10

It is 60years since the discovery of the correct number of chromosomes in 1956; the field of cytogenetics had evolved. The late evolution of this field with respect to other fields is primarily due to the underdevelopment of lenses and imaging techniques. With the advent of the new technologies, especially automation and evolution of advanced compound microscopes, cytogenetics drastically leaped further to greater heights. This review describes the historic events that had led to the development of human cytogenetics with a special attention about the history of cytogenetics in India, its present status, and future. Apparently, this review provides a brief account into the insights of the early laboratory establishments, funding, and the German collaborations. The details of the Indian cytogeneticists establishing their labs, promoting the field, and offering the chromosomal diagnostic services are described. The detailed study of chromosomes helps in increasing the knowledge of the chromosome structure and function. The delineation of the chromosomal rearrangements using cytogenetics and molecular cytogenetic techniques pays way in identifying the molecular mechanisms involved in the chromosomal rearrangement. Although molecular cytogenetics is greatly developing, the conventional cytogenetics still remains the gold standard in the diagnosis of various numerical chromosomal aberrations and a few structural aberrations. The history of cytogenetics and its importance even in the era of molecular cytogenetics are discussed. Copyright © 2016 Elsevier B.V. All rights reserved.

Maternal reflective functioning among mothers with childhood maltreatment histories: links to sensitive parenting and infant attachment security.

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Stacks, Ann M; Muzik, Maria; Wong, Kristyn; Beeghly, Marjorie; Huth-Bocks, Alissa; Irwin, Jessica L; Rosenblum, Katherine L

2014-01-01

This study examined relationships among maternal reflective functioning, parenting, infant attachment, and demographic risk in a relatively large (N = 83) socioeconomically diverse sample of women with and without a history of childhood maltreatment and their infants. Most prior research on parental reflective functioning has utilized small homogenous samples. Reflective functioning was assessed with the Parent Development Interview, parenting was coded from videotaped mother-child interactions, and infant attachment was evaluated in Ainsworth's Strange Situation by independent teams of reliable coders masked to maternal history. Reflective functioning was associated with parenting sensitivity and secure attachment, and inversely associated with demographic risk and parenting negativity; however, it was not associated with maternal maltreatment history or PTSD. Parenting sensitivity mediated the relationship between reflective functioning and infant attachment, controlling for demographic risk. Findings are discussed in the context of prior research on reflective functioning and the importance of targeting reflective functioning in interventions.

A demographic-economic explanation of political stability: Mauritius as a microcosm.

Science.gov (United States)

Lempert, D

1987-06-01

"This paper examines current models of economic and political development--social modernization theory, political and economic characteristics of stable regimes, and cross country analysis of political stability--and tests them on the Indian Ocean Island of Mauritius. The analysis continues with a causal explanation for political stability in Mauritius' recent history, derived from an examination of economic policies and demographic patterns. Political change in Mauritius over the past sixty years seems to be explained best by a model for political stability which integrates specific economic and demographic factors. The model, applicable to development in other third world nations, revises Malthus' conclusion that population and economic conditions move in an oscillatory relationship and replaces it with a more comprehensive theory, suggesting that political stability is a function of both economic development and a repeating cyclical relationship between economics and population." excerpt

Genetic evidence for a Paleolithic human population expansion in Africa

Science.gov (United States)

Reich, David E.; Goldstein, David B.

1998-01-01

Human populations have undergone dramatic expansions in size, but other than the growth associated with agriculture, the dates and magnitudes of those expansions have never been resolved. Here, we introduce two new statistical tests for population expansion, which use variation at a number of unlinked genetic markers to study the demographic histories of natural populations. By analyzing genetic variation in various aboriginal populations from throughout the world, we show highly significant evidence for a major human population expansion in Africa, but no evidence of expansion outside of Africa. The inferred African expansion is estimated to have occurred between 49,000 and 640,000 years ago, certainly before the Neolithic expansions, and probably before the splitting of African and non-African populations. In showing a significant difference between African and non-African populations, our analysis supports the unique role of Africa in human evolutionary history, as has been suggested by most other genetic work. In addition, the missing signal in non-African populations may be the result of a population bottleneck associated with the emergence of these populations from Africa, as postulated in the “Out of Africa” model of modern human origins. PMID:9653150

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

Science.gov (United States)

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

2014-07-01

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

Neighbourhood Deprivation, Individual-Level Familial and Socio-Demographic Factors and Diagnosed Childhood Obesity: A Nationwide Multilevel Study from Sweden

Directory of Open Access Journals (Sweden)

Xinjun Li

2014-08-01

Full Text Available Objectives: To examine whether there is an association between neighbourhood deprivation and diagnosed childhood obesity, after accounting for family- and individual-level socio-demographic characteristics. Methods: An open cohort of all children aged 0-14 years was followed between January 1, 2000 and December 31, 2010. Childhood residential locations were geocoded and classified according to neighbourhood deprivation. Data were analysed by multilevel logistic regression, with family- and individual-level characteristics at the first level and level of neighbourhood deprivation at the second level. Results: During the study period, among a total of 948,062 children, 10,799 were diagnosed with childhood obesity. Age-adjusted cumulative incidence for diagnosed childhood obesity increased with increasing level of neighbourhood deprivation. Incidence of diagnosed childhood obesity increased with increasing neighbourhood-level deprivation across all family and individual-level socio-demographic categories. The odds ratio (OR for diagnosed childhood obesity for those living in high-deprivation neighbourhoods versus those living in low-deprivation neighbourhoods was 2.44 (95% confidence interval (CI = 2.22-2.68. High neighbourhood deprivation remained significantly associated with higher odds of diagnosed childhood obesity after adjustment for family- and individual-level socio-demographic characteristics (OR = 1.70, 95% CI = 1.55-1.89. Age, middle level family income, maternal marital status, low level education, living in large cities, advanced paternal and maternal age, family history of obesity, parental history of diabetes, chronic obstructive pulmonary disease, alcoholism and personal history of diabetes were all associated with higher odds of diagnosed childhood obesity. Conclusions: Our results suggest that neighbourhood characteristics affect the odds of diagnosed childhood obesity independently of family- and individual-level socio-demographic

Sensitivity analysis of effective population size to demographic parameters in house sparrow populations.

Science.gov (United States)

Stubberud, Marlene Waege; Myhre, Ane Marlene; Holand, Håkon; Kvalnes, Thomas; Ringsby, Thor Harald; Saether, Bernt-Erik; Jensen, Henrik

2017-05-01

The ratio between the effective and the census population size, Ne/N, is an important measure of the long-term viability and sustainability of a population. Understanding which demographic processes that affect Ne/N most will improve our understanding of how genetic drift and the probability of fixation of alleles is affected by demography. This knowledge may also be of vital importance in management of endangered populations and species. Here, we use data from 13 natural populations of house sparrow (Passer domesticus) in Norway to calculate the demographic parameters that determine Ne/N. Using the global variance-based Sobol' method for the sensitivity analyses, we found that Ne/N was most sensitive to demographic variance, especially among older individuals. Furthermore, the individual reproductive values (that determine the demographic variance) were most sensitive to variation in fecundity. Our results draw attention to the applicability of sensitivity analyses in population management and conservation. For population management aiming to reduce the loss of genetic variation, a sensitivity analysis may indicate the demographic parameters towards which resources should be focused. The result of such an analysis may depend on the life history and mating system of the population or species under consideration, because the vital rates and sex-age classes that Ne/N is most sensitive to may change accordingly. © 2017 John Wiley & Sons Ltd.

Dimensions of Rational Decision-Making during the Demographic Transition; Aranjuez (Spain Revisited

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David Reher

2015-03-01

Full Text Available A set of linked reproductive histories taken from the Spanish town of Aranjuez during the demographic transition is used to address key issues regarding reproductive change and reproductive choice. This paper builds on the existing literature and especially on the findings first shown in Reher & Sanz-Gimeno (2007 and in Van Poppel et al. (2012 where the links between childhood survival and reproductive decision-making were specified. This paper goes beyond the original ones in two important ways: (a the sex composition of the surviving sibset is included in the analysis and (b behavior is modeled by means of event history analysis. In these models, controls for the survival status of the previous child are introduced so as to distinguish between biological factors related to the cessation of breastfeeding and both short term (child replacement and more long-term reproductive strategies. The results offer convincing proof that couples were continually regulating their fertility in order to achieve reproductive goals both in terms of net fertility and of the sex composition of the resulting sibset. Here results show that both sexes were desired by parents but that lack of surviving males had greater influence on fertility behavior. As expected, controls for the survival status of the previous-born child were important though they did not diminish appreciably the overall effect of the number of surviving offspring. This article offers strong proof for the existence of active decision-making during the demographic transition and applies a method to model these behaviors over the full reproductive history of the couple.

Inferring Genetic Variation and Demographic History of Michelia yunnanensis Franch. (Magnoliaceae from Chloroplast DNA Sequences and Microsatellite Markers

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Shikang Shen

2017-04-01

Full Text Available Michelia yunnanensis Franch., is a traditional ornamental, aromatic, and medicinal shrub that endemic to Yunnan Province in southwest China. Although the species has a large distribution pattern and is abundant in Yunnan Province, the populations are dramatically declining because of overexploitation and habitat destruction. Studies on the genetic variation and demography of endemic species are necessary to develop effective conservation and management strategies. To generate such knowledge, we used 3 pairs of universal cpDNA markers and 10 pairs of microsatellite markers to assess the genetic diversity, genetic structure, and demographic history of 7 M. yunnanensis populations. We calculated a total of 88 alleles for 10 polymorphic loci and 10 haplotypes for a combined 2,089 bp of cpDNA. M. yunnanensis populations showed high genetic diversity (Ho = 0.551 for nuclear markers and Hd = 0.471 for cpDNA markers and low genetic differentiation (FST = 0.058. Geographical structure was not found among M. yunnanensis populations. Genetic distance and geographic distance were not correlated (P > 0.05, which indicated that geographic isolation is not the primary cause of the low genetic differentiation of M. yunnanensis. Additionally, M. yunnanensis populations contracted ~20,000–30,000 years ago, and no recent expansion occurred in current populations. Results indicated that the high genetic diversity of the species and within its populations holds promise for effective genetic resource management and sustainable utilization. Thus, we suggest that the conservation and management of M. yunnanensis should address exotic overexploitation and habitat destruction.

Habitat and scale shape the demographic fate of the keystone sea urchin Paracentrotus lividus in Mediterranean macrophyte communities.

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Patricia Prado

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

Phylodynamics of Merkel-cell polyomavirus and human polyomavirus 6: A long-term history with humans.

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Torres, Carolina; Barrios, Melina Elizabeth; Cammarata, Robertina Viviana; Victoria, Matías; Fernandez-Cassi, Xavier; Bofill-Mas, Silvia; Colina, Rodney; Blanco Fernández, María Dolores; Mbayed, Viviana Andrea

2018-04-20

New human polyomaviruses have been described in the last years, including the Merkel-cell polyomavirus (MCPyV; Human polyomavirus 5) and the Human polyomavirus 6 (HPyV6). Although their infection is usually asymptomatic, in immunocompromised host can cause life-threatening pathologies, such as the Merkel cell carcinoma, an aggressive skin neoplasia associated to the MCPyV. Despite being prevalent viruses in population, epidemiological data from South America are scarce, as well as the characterization of the viral types circulating and their origin. The aims of this work were to describe MCPyV and HPyV6 from environmental samples with different geographical origin and to analyze their phylogenetic and evolutionary histories, particularly for MCPyV. Partial and complete genome sequences were obtained from sewage samples from Argentina, Uruguay and Spain. A total number of 87 sequences were obtained for MCPyV and 33 for HPyV6. Phylogenetic analysis showed that MCPyV sequences distributed according to their geographic origin in Europe/North America, Africa, Asia, South America and Oceania groups, suggesting that viral diversification might have followed human migrations across the globe. In particular, viruses from Argentina associated with Europe/North America and South America genotypes, whereas those from Uruguay and Spain also grouped with Africa genotype, reflecting the origin of the current population in each country, which could arrive not only during ancient human migration but also during recent migratory events. In addition, the South American group presented a high level of clusterization, showing internal clusters that could be related to specific locations, such as French Guiana and Brazil or the Southern region into South America, such as Argentina and Uruguay, suggesting a long term evolutionary process in the region. Additionally, in this work, we carried out the first analysis about the evolutionary history of MCPyV trough the integration of

Literature, history and the humanization of bioethics.

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Emmerich, Nathan

2011-02-01

This paper considers the disciplines of literature and history and the contributions each makes to the discourse of bioethics. In each case I note the pedagogic ends that can be enacted though the appropriate use of the each of these disciplines in the sphere of medical education, particularly in the medical ethics classroom.(1) I then explore the contribution that both these disciplines and their respective methodologies can and do bring to the academic field of bioethics. I conclude with a brief consideration of the relations between literature and history with particular attention to the possibilities for a future bioethics informed by history and literature after the empirical turn. © 2010 Blackwell Publishing Ltd.

Teaching about Religion in History Classes: Sacred and Secular History.

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Abrahamson, Brant; Smith, Fred

In teaching about religion there is the fundamental distinction between secular history, which is restricted to natural cause and effect relationships, and sacred histories, which assume that a spirit world exists and that human/divine interaction has taken place. In the United States, the academically approved way of dealing with these…

An early history of human breast cancer: West meets East.

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Yan, Shou-He

2013-09-01

Cancer has been increasingly recognized as a global issue. This is especially true in countries like China, where cancer incidence has increased likely because of changes in environment and lifestyle. However, cancer is not a modern disease; early cases have been recorded in ancient medical books in the West and in China. Here, we provide a brief history of cancer, focusing on cancer of the breast, and review the etymology of ai, the Chinese character for cancer. Notable findings from both Western and Chinese traditional medicine are presented to give an overview of the most important, early contributors to our evolving understanding of human breast cancer. We also discuss the earliest historical documents to record patients with breast cancer.

Linkage disequilibrium and demographic history of the isolated population of the Faroe Islands

DEFF Research Database (Denmark)

Jorgensen, Tove H; Degn, Birte; Wang, August G

2002-01-01

The isolated population of the Faroe Islands has a history of recent expansion after being limited to a small size for centuries. Such an isolated population may be ideal for linkage disequilibrium mapping of disease genes if linkage disequilibrium (LD) extends over large regions. Analyses of 18 ...

Detecting the Evolution of Deliberate Fertility Control before the Demographic Transition in Germany

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Aliaksandr Amialchuk

2012-10-01

Full Text Available BACKGROUND Pervious literature has established the existence of deliberate non-parity-specific fertility control in pre-transitional populations. However, less focus has been given to the timing of its onset. In addition, previous studies focused on the changes in fertility in response to the local prices of grains, which may be endogenous. OBJECTIVE This paper studies the emergence and evolution of deliberate fertility control by investigating the link between child mortality and economic stress on the one hand and non-parity-specific birth control on the other, in historic German villages between 1700 and 1900. METHODS Birth histories from fourteen German villages (1700-1900 and rye price series are used in a micro-level event history analysis. The fertility response of second and higher-order births to the mortality of children over age two and exogenous fluctuations in rye price are used as measures of the extent of deliberate non-parity-specific birth control. RESULTS Over the course of the demographic transition, the effect of the death of children generally increases after controlling for the effect of the death of children less than two years old. The negative fertility response to high rye prices before and in the year immediately following the price change occurred only after 1800. CONCLUSIONS The replacement and insurance effects associated with child mortality generally increased before the demographic transition. The emergence of the negative effect of high rye prices on fertility after 1800 further supports the presence and evolution of deliberate non-parity-specific fertility control before the demographic transition.

Earliest evidence of modern human life history in North African early Homo sapiens.

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Smith, Tanya M; Tafforeau, Paul; Reid, Donald J; Grün, Rainer; Eggins, Stephen; Boutakiout, Mohamed; Hublin, Jean-Jacques

2007-04-10

Recent developmental studies demonstrate that early fossil hominins possessed shorter growth periods than living humans, implying disparate life histories. Analyses of incremental features in teeth provide an accurate means of assessing the age at death of developing dentitions, facilitating direct comparisons with fossil and modern humans. It is currently unknown when and where the prolonged modern human developmental condition originated. Here, an application of x-ray synchrotron microtomography reveals that an early Homo sapiens juvenile from Morocco dated at 160,000 years before present displays an equivalent degree of tooth development to modern European children at the same age. Crown formation times in the juvenile's macrodont dentition are higher than modern human mean values, whereas root development is accelerated relative to modern humans but is less than living apes and some fossil hominins. The juvenile from Jebel Irhoud is currently the oldest-known member of Homo with a developmental pattern (degree of eruption, developmental stage, and crown formation time) that is more similar to modern H. sapiens than to earlier members of Homo. This study also underscores the continuing importance of North Africa for understanding the origins of human anatomical and behavioral modernity. Corresponding biological and cultural changes may have appeared relatively late in the course of human evolution.

Thinking and Caring about Indigenous Peoples' Human Rights: Swedish Students Writing History beyond Scholarly Debate

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Nygren, Thomas

2016-01-01

According to national and international guidelines, schools should promote historical thinking and foster moral values. Scholars have debated, but not analysed in depth in practice, whether history education can and should hold a normative dimension. This study analyses current human rights education in two Swedish senior high school groups, in…

Using demographic characteristics of populations to detect spatial fragmentation following suspected ebola outbreaks in great apes.

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Genton, Céline; Cristescu, Romane; Gatti, Sylvain; Levréro, Florence; Bigot, Elodie; Motsch, Peggy; Le Gouar, Pascaline; Pierre, Jean-Sébastien; Ménard, Nelly

2017-09-01

Demographic crashes due to emerging diseases can contribute to population fragmentation and increase extinction risk of small populations. Ebola outbreaks in 2002-2004 are suspected to have caused a decline of more than 80% in some Western lowland gorilla (Gorilla gorilla gorilla) populations. We investigated whether demographic indicators of this event allowed for the detection of spatial fragmentation in gorilla populations. We collected demographic data from two neighbouring populations: the Lokoué population, suspected to have been affected by an Ebola outbreak (followed from 2001 to 2014), and the Romani population, of unknown demographic status before Ebola outbreaks (followed from 2005 to 2014). Ten years after the outbreak, the Lokoué population is slowly recovering and the short-term demographic indicators of a population crash were no longer detectable. The Lokoué population has not experienced any additional demographic perturbation over the past decade. The Romani population did not show any of the demographic indicators of a population crash over the past decade. Its demographic structure remained similar to that of unaffected populations. Our results highlighted that the Ebola disease could contribute to fragmentation of gorilla populations due to the spatially heterogeneous impact of its outbreaks. The demographic structure of populations (i.e., age-sex and group structure) can be useful indicators of a possible occurrence of recent Ebola outbreaks in populations without known history, and may be more broadly used in other emerging disease/species systems. Longitudinal data are critical to our understanding of the impact of emerging diseases on wild populations and their conservation. © 2017 Wiley Periodicals, Inc.

Demographic history of european populations of Arabidopsis thaliana.

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Olivier François

2008-05-01

Full Text Available The model plant species Arabidopsis thaliana is successful at colonizing land that has recently undergone human-mediated disturbance. To investigate the prehistoric spread of A. thaliana, we applied approximate Bayesian computation and explicit spatial modeling to 76 European accessions sequenced at 876 nuclear loci. We find evidence that a major migration wave occurred from east to west, affecting most of the sampled individuals. The longitudinal gradient appears to result from the plant having spread in Europe from the east approximately 10,000 years ago, with a rate of westward spread of approximately 0.9 km/year. This wave-of-advance model is consistent with a natural colonization from an eastern glacial refugium that overwhelmed ancient western lineages. However, the speed and time frame of the model also suggest that the migration of A. thaliana into Europe may have accompanied the spread of agriculture during the Neolithic transition.

A Hacker in Every History Department: An Intelligent Radical’s Guide to the Digital Humanities

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Claire Bond Potter

2014-05-01

Full Text Available Rather than making the next generation of history Ph.D.'s redundant or contingent laborers, digital technologies and the Internet have the potential to revive full time teaching. Although Digital Humanities is growing rapidly as a field, few history departments have tapped into the power of its pedagogy to teach critical thinking and research skills. Focused on making, rather than banking, knowledge, DH emphasizes flexibility and originality. Furthermore, by giving historians the technical and design skills to work outside the academy, it not only produces a new source of employment but would force universities to compete for historians just as they do for lawyers, economists and scientists.

Heterogeneity of life histories in a nonhuman primate population

DEFF Research Database (Denmark)

Hernández Pacheco, Raisa; Steiner, Uli

2014-01-01

histories within a primate population is generated by density-dependent dynamics, the demographic data of Cayo Santiago rhesus macaques over 40 years and 7000 individuals was used. A multi-stage model using a first-order Markov process describing reproductive dynamics was constructed and annual entropy...

EJSCREEN Demographic Indicators 2015 Public

Science.gov (United States)

EJSCREEN uses demographic factors as very general indicators of a community's potential susceptibility to the types of environmental factors included in this screening tool. There are six demographic indicators: Demographic Index, Supplementary Demographic Index, Individuals under Age 5, Individuals over Age 64, Percent Low-Income, Linguistic Isolation, Percent Minority, and Less than High School Education.

Responsive survey design, demographic data collection, and models of demographic behavior.

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Axinn, William G; Link, Cynthia F; Groves, Robert M

2011-08-01

To address declining response rates and rising data-collection costs, survey methodologists have devised new techniques for using process data ("paradata") to address nonresponse by altering the survey design dynamically during data collection. We investigate the substantive consequences of responsive survey design-tools that use paradata to improve the representative qualities of surveys and control costs. By improving representation of reluctant respondents, responsive design can change our understanding of the topic being studied. Using the National Survey of Family Growth Cycle 6, we illustrate how responsive survey design can shape both demographic estimates and models of demographic behaviors based on survey data. By juxtaposing measures from regular and responsive data collection phases, we document how special efforts to interview reluctant respondents may affect demographic estimates. Results demonstrate the potential of responsive survey design to change the quality of demographic research based on survey data.

The neolithic demographic transition in Europe: correlation with juvenility index supports interpretation of the summed calibrated radiocarbon date probability distribution (SCDPD as a valid demographic proxy.

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Sean S Downey

Full Text Available Analysis of the proportion of immature skeletons recovered from European prehistoric cemeteries has shown that the transition to agriculture after 9000 BP triggered a long-term increase in human fertility. Here we compare the largest analysis of European cemeteries to date with an independent line of evidence, the summed calibrated date probability distribution of radiocarbon dates (SCDPD from archaeological sites. Our cemetery reanalysis confirms increased growth rates after the introduction of agriculture; the radiocarbon analysis also shows this pattern, and a significant correlation between both lines of evidence confirms the demographic validity of SCDPDs. We analyze the areal extent of Neolithic enclosures and demographic data from ethnographically known farming and foraging societies and we estimate differences in population levels at individual sites. We find little effect on the overall shape and precision of the SCDPD and we observe a small increase in the correlation with the cemetery trends. The SCDPD analysis supports the hypothesis that the transition to agriculture dramatically increased demographic growth, but it was followed within centuries by a general pattern of collapse even after accounting for higher settlement densities during the Neolithic. The study supports the unique contribution of SCDPDs as a valid demographic proxy for the demographic patterns associated with early agriculture.

Human Rights, History of

NARCIS (Netherlands)

de Baets, Antoon; Wright, James

2015-01-01

In this article, six basic debates about human rights are clarified from a historical perspective: the origin of human rights as moral rights connected to the natural law doctrine and opposed to positive rights; the wave of criticism of their abstract and absolute character by nineteenth-century

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

Science.gov (United States)

Soliani, Lamberto; Rossi, Orazio

1992-09-01

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

The research history of the human behaviour from the probabilistic safety analysis viewpoint

International Nuclear Information System (INIS)

Pyy, P.

1993-01-01

The so called human errors have always been apart of the everyday life of the mankind. In that sense, the discussion on man has a contributor to the operational safety of nuclear power plants is nothing new. It is interesting, that there do not exist widely accepted definitions of the human error nor the human reliability. Some of them are discussed at the beginning of this article. The second Chapter discusses the past and today of the research of man as a contributor to safety. Similarly, the development of Human Reliability Analysis (HRA) is described. The article, then, discusses the methods used in the contemporary HRA. The division between the identification of important human activities and their probability estimation is made. Especially, the pros and cons of the approaches and data sources used in the HRA are reviewed on a coarce level. At the end, a view on the use of expert judgment is given. The human behaviour has been an endless topic of research in the history - and will be it in future as well. In the conclusion of the article an opinion is given on the development during the past 30 years. Then, a rapid view on the possible future of the area is given. (orig.)

Biological effects of space radiation on human cells. History, advances and outcomes

International Nuclear Information System (INIS)

Maalouf, M.; Foray, N.; Durante, M.

2011-01-01

Exposure to radiation is one of the main concerns for space exploration by humans. By focusing deliberately on the works performed on human cells, we endeavored to review, decade by decade, the technological developments and conceptual advances of space radiation biology. Despite considerable efforts, the cancer and the toxicity risks remain to be quantified: the nature and the frequency of secondary heavy ions need to be better characterized in order to estimate their contribution to the dose and to the final biological response; the diversity of radiation history of each astronaut and the impact of individual susceptibility make very difficult any epidemiological analysis for estimating hazards specifically due to space radiation exposure. Cytogenetic data undoubtedly revealed that space radiation exposure produce significant damage in cells. However, our knowledge of the basic mechanisms specific to low-dose, to repeated doses and to adaptive response is still poor. The application of new radiobiological techniques, like immunofluorescence, and the use of human tissue models different from blood, like skin fibroblasts, may help in clarifying all the above items. (author)

Accuracy of Demographic Inferences from the Site Frequency Spectrum: The Case of the Yoruba Population.

Science.gov (United States)

Lapierre, Marguerite; Lambert, Amaury; Achaz, Guillaume

2017-05-01

Some methods for demographic inference based on the observed genetic diversity of current populations rely on the use of summary statistics such as the Site Frequency Spectrum (SFS). Demographic models can be either model-constrained with numerous parameters, such as growth rates, timing of demographic events, and migration rates, or model-flexible, with an unbounded collection of piecewise constant sizes. It is still debated whether demographic histories can be accurately inferred based on the SFS. Here, we illustrate this theoretical issue on an example of demographic inference for an African population. The SFS of the Yoruba population (data from the 1000 Genomes Project) is fit to a simple model of population growth described with a single parameter ( e.g. , founding time). We infer a time to the most recent common ancestor of 1.7 million years (MY) for this population. However, we show that the Yoruba SFS is not informative enough to discriminate between several different models of growth. We also show that for such simple demographies, the fit of one-parameter models outperforms the stairway plot, a recently developed model-flexible method. The use of this method on simulated data suggests that it is biased by the noise intrinsically present in the data. Copyright © 2017 by the Genetics Society of America.

Dancing with Demographers.

Science.gov (United States)

Robertson, Heather-Jane

2000-01-01

Demographic projections concerning the shortage of teachers in Canada, their pay scale, the feminization of teaching, the gender gap in salaries, and teacher autonomy have often been incorrect, or correct for the wrong reasons. Instead of relying on demographic predictions, teachers should contemplate who they really want to be professionally,…

Family history of alcoholism and the human brain response to oral sucrose.

Science.gov (United States)

Eiler, William J A; Dzemidzic, Mario; Soeurt, Christina M; Carron, Claire R; Oberlin, Brandon G; Considine, Robert V; Harezlak, Jaroslaw; Kareken, David A

2018-01-01

A heightened hedonic response to sweet tastes has been associated with increased alcohol preference and alcohol consumption in both humans and animals. The principal goal of this study was to examine blood oxygenation level dependent (BOLD) activation to high- and low-concentration sweet solutions in subjects who are either positive (FHP) or negative (FHN) for a family history of alcoholism. Seventy-four non-treatment seeking, community-recruited, healthy volunteers (22.8 ± 1.6 SD years; 43% men) rated a range of sucrose concentrations in a taste test and underwent functional magnetic resonance imaging (fMRI) during oral delivery of water, 0.83 M, and 0.10 M sucrose. Sucrose compared to water produced robust activation in primary gustatory cortex, ventral insula, amygdala, and ventral striatum. FHP subjects displayed greater bilateral amygdala activation than FHN subjects in the low sucrose concentration (0.10 M). In secondary analyses, the right amygdala response to the 0.10 M sucrose was greatest in FHP women. When accounting for group differences in drinks per week, the family history groups remained significantly different in their right amygdala response to 0.10 M sucrose. Our findings suggest that the brain response to oral sucrose differs with a family history of alcoholism, and that this response to a mildly reinforcing primary reward might be an endophenotypic marker of alcoholism risk.

Dissemination and geovisualization of territorial entities' history

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Christine Plumejeaud

2014-06-01

Full Text Available This paper describes an innovative solution for geovisualization of the demographic and administrative history of French municipalities, named "communes" in French. This solution allows for the open dissemination of such data. The challenge is to provide a web interface for unskilled users in order to help them understand complex information about the demographic evolution of French territories. Our approach combines interactive thematic, spatial, and temporal views. We describe our architecture, based on open-source technologies, and the organization of this imperfect geo-historical information in our spatiotemporal database. Our second contribution concerns the concept of an acquaintance graph that has been used to obtain an efficient design with good performance in our geovisualization website.

Child maltreatment syndrome: demographics and developmental issues of inpatient cases.

Science.gov (United States)

Ngiam, Xin Ying; Kang, Ying Qi; Aishworiya, Ramkumar; Kiing, Jennifer; Law, Evelyn Chung Ning

2015-11-01

This study aimed to describe the demographic, social, developmental and behavioural profile of children hospitalised for alleged child maltreatment syndrome (CMS). This study was a retrospective review of the consecutive inpatient records of children (0-16 years) admitted to the National University Hospital, Singapore, for alleged CMS over a three-year period. Descriptive data on the demographic characteristics, alleged maltreatment, medical and developmental histories, and family background of these children were collected and analysed. Chi-square statistics were used to test whether family factors were associated with the type of maltreatment and the presence of developmental disorders. A total of 89 children, who accounted for 90 admission cases, were studied. Physical abuse (70.0%) was the most common, followed by neglect (11.1%) and sexual abuse (7.8%). Child protection services had already been involved in 29.2% of the cases prior to the child's admission. Children who were victims of abuse were more likely to come from homes with a prior history of domestic violence (p = 0.028). Financial difficulty was found to be a risk factor for neglect (p = 0.005). Among the 89 children, 15.7% were found to have developmental disorders and 10.1% had mental health diagnoses. Children who had developmental disorders were more likely to have a parent with a mental health disorder (p = 0.002). A sizeable proportion of the children admitted for alleged CMS had developmental or behavioural disorders. Clinicians have a role in ensuring that these children have appropriate follow-up plans. Children from high-risk families should be screened for maltreatment.

Late Pleistocene climate change and the global expansion of anatomically modern humans

Science.gov (United States)

Eriksson, Anders; Betti, Lia; Friend, Andrew D.; Lycett, Stephen J.; Singarayer, Joy S.; von Cramon-Taubadel, Noreen; Valdes, Paul J.; Balloux, Francois; Manica, Andrea

2012-01-01

The extent to which past climate change has dictated the pattern and timing of the out-of-Africa expansion by anatomically modern humans is currently unclear [Stewart JR, Stringer CB (2012) Science 335:1317–1321]. In particular, the incompleteness of the fossil record makes it difficult to quantify the effect of climate. Here, we take a different approach to this problem; rather than relying on the appearance of fossils or archaeological evidence to determine arrival times in different parts of the world, we use patterns of genetic variation in modern human populations to determine the plausibility of past demographic parameters. We develop a spatially explicit model of the expansion of anatomically modern humans and use climate reconstructions over the past 120 ky based on the Hadley Centre global climate model HadCM3 to quantify the possible effects of climate on human demography. The combinations of demographic parameters compatible with the current genetic makeup of worldwide populations indicate a clear effect of climate on past population densities. Our estimates of this effect, based on population genetics, capture the observed relationship between current climate and population density in modern hunter–gatherers worldwide, providing supporting evidence for the realism of our approach. Furthermore, although we did not use any archaeological and anthropological data to inform the model, the arrival times in different continents predicted by our model are also broadly consistent with the fossil and archaeological records. Our framework provides the most accurate spatiotemporal reconstruction of human demographic history available at present and will allow for a greater integration of genetic and archaeological evidence. PMID:22988099

Cannabis use and family history in adolescent first episode ...

African Journals Online (AJOL)

Objectives: To investigate the clinical correlates of cannabis use in adolescents with first episode psychosis (FEP). Methods: Inpatient psychiatric records provided demographic, lifetime cannabis use, family history of mental illness, and clinical data on 45 FEP adolescents, aged 12–18 years, admitted to a psychiatric unit in ...

Subacute Sclerosing Panencephalitis: Clinical and Demographic Characteristics

International Nuclear Information System (INIS)

Rafique, A.; Amjad, N.; Chand, P.; Ahmed, K.; Ibrahim, S.; Zaidi, S. S. Z.; Rana, M. S.

2014-01-01

Objective: To determine the clinical and demographic characteristics of children diagnosed with Subacute sclerosing panencephalitis (SSPE). Study Design: Case series. Place and Duration of Study: The Aga Khan University Hospital, Karachi, from January 2000 to June 2012. Methodology: A retrospective analysis was done, regarding medical charts of 43 children under the age of 16 years with a discharge diagnosis of SSPE. Demographic and clinical characteristics were recorded. Results were expressed as percentages. Results: Most of the 43 patients were male (72%). The average age at presentation was 8.7 years with average duration of symptoms being 100.6 days. History of measles was present in 17 patients (39.5%). All children had seizures at presentation and 65% had cognitive impairment. Most patients required poly therapy for control of seizures. Sodium valproate was the most commonly used anti-epileptic agent; Isoprinosine was tried in 22 (51%) patients. CSF for antimeasles antibodies was positive in approximately 86% of the 40 (93%) children. EEG showed burst suppression pattern in 36 (83.7%) cases. Forty-two patients (97.6%) were discharged home in a vegetative state. Conclusion: SSPE is progressive neurodegenerative disorder. It can be prevented by timely immunization against measles. Measles antibody in the CSF is diagnostic for SSPE and is helpful in early diagnosis. Most patients experience a gradual but progressive decline in motor and cognitive functions. (author)

Family Health Histories and Their Impact on Retirement Confidence.

Science.gov (United States)

Zick, Cathleen D; Mayer, Robert N; Smith, Ken R

2015-08-01

Retirement confidence is a key social barometer. In this article, we examine how personal and parental health histories relate to working-age adults' feelings of optimism or pessimism about their overall retirement prospects. This study links survey data on retirement planning with information on respondents' own health histories and those of their parents. The multivariate models control for the respondents' socio-demographic and economic characteristics along with past retirement planning activities when estimating the relationships between family health histories and retirement confidence. Retirement confidence is inversely related to parental history of cancer and cardiovascular disease but not to personal health history. In contrast, retirement confidence is positively associated with both parents being deceased. As members of the public become increasingly aware of how genetics and other family factors affect intergenerational transmission of chronic diseases, it is likely that the link between family health histories and retirement confidence will intensify. © The Author(s) 2015.

The offspring quantity–quality trade-off and human fertility variation

Science.gov (United States)

Lawson, David W.; Borgerhoff Mulder, Monique

2016-01-01

The idea that trade-offs between offspring quantity and quality shape reproductive behaviour has long been central to economic perspectives on fertility. It also has a parallel and richer theoretical foundation in evolutionary ecology. We review the application of the quantity–quality trade-off concept to human reproduction, emphasizing distinctions between clutch size and lifetime fertility, and the wider set of forces contributing to fertility variation in iteroparous and sexually reproducing species like our own. We then argue that in settings approximating human evolutionary history, several factors limit costly sibling competition. Consequently, while the optimization of quantity–quality trade-offs undoubtedly shaped the evolution of human physiology setting the upper limits of reproduction, we argue it plays a modest role in accounting for socio-ecological and individual variation in fertility. Only upon entering the demographic transition can fertility limitation be clearly interpreted as strategically orientated to advancing offspring quality via increased parental investment per child, with low fertility increasing descendant socio-economic success, although not reproductive success. We conclude that existing economic and evolutionary literature has often overemphasized the centrality of quantity–quality trade-offs to human fertility variation and advocate for the development of more holistic frameworks encompassing alternative life-history trade-offs and the evolved mechanisms guiding their resolution. PMID:27022072

Is prevalence of colorectal polyps higher in patients with family history of colorectal cancer?

OpenAIRE

Murad-Regadas, Sthela Maria; Bezerra, Carla Camila Rocha; Peixoto, Ana Ligia Rocha; Regadas, Francisco Sérgio Pinheiro; Rodrigues, Lusmar Veras; Siebra, José Airton Gonçalves; da Silva Fernandes, Graziela Olivia; Vasconcelos, Rafael Aragão

2015-01-01

ABSTRACTObjectives:To assess the prevalence of polyps in patients with a family history of colorectal cancer, in comparison to asymptomatic individuals with indication for screening.Methods:A prospective study in a group of patients who underwent colonoscopy between 2012 and 2014. Patients were divided into two groups: Group I: no family history of colorectal cancer, and Group II: with a family history in first-degree relatives. Demographic characteristics, findings on colonoscopy...

"Human Potential" and Progressive Pedagogy: A Long Cultural History of the Ambiguity of "Race" and "Intelligence"

Science.gov (United States)

Oland, Trine

2012-01-01

This article examines the cultural constructs of progressive pedagogy in Danish school pedagogy and its emerging focus on the child's human potential from the 1920s to the 1950s. It draws on Foucault's notion of "dispositifs" and the "elements of history," encircling a complex transformation of continuity and discontinuity of…

History of Science and History of Philologies.

Science.gov (United States)

Daston, Lorraine; Most, Glenn W

2015-06-01

While both the sciences and the humanities, as currently defined, may be too heterogeneous to be encompassed within a unified historical framework, there is good reason to believe that the history of science and the history of philologies both have much to gain by joining forces. This collaboration has already yielded striking results in the case of the history of science and humanist learning in early modern Europe. This essay argues that first, philology and at least some of the sciences (e.g., astronomy) remained intertwined in consequential ways well into the modern period in Western cultures; and second, widening the scope of inquiry to include other philological traditions in non-Western cultures offers rich possibilities for a comparative history of learned practices. The focus on practices is key; by shifting the emphasis from what is studied to how it is studied, deep commonalities emerge among disciplines--and intellectual traditions--now classified as disparate.

User Interface History

DEFF Research Database (Denmark)

Jørgensen, Anker Helms; Myers, Brad A

2008-01-01

User Interfaces have been around as long as computers have existed, even well before the field of Human-Computer Interaction was established. Over the years, some papers on the history of Human-Computer Interaction and User Interfaces have appeared, primarily focusing on the graphical interface e...

Accounting for measurement error in human life history trade-offs using structural equation modeling.

Science.gov (United States)

Helle, Samuli

2018-03-01

Revealing causal effects from correlative data is very challenging and a contemporary problem in human life history research owing to the lack of experimental approach. Problems with causal inference arising from measurement error in independent variables, whether related either to inaccurate measurement technique or validity of measurements, seem not well-known in this field. The aim of this study is to show how structural equation modeling (SEM) with latent variables can be applied to account for measurement error in independent variables when the researcher has recorded several indicators of a hypothesized latent construct. As a simple example of this approach, measurement error in lifetime allocation of resources to reproduction in Finnish preindustrial women is modelled in the context of the survival cost of reproduction. In humans, lifetime energetic resources allocated in reproduction are almost impossible to quantify with precision and, thus, typically used measures of lifetime reproductive effort (e.g., lifetime reproductive success and parity) are likely to be plagued by measurement error. These results are contrasted with those obtained from a traditional regression approach where the single best proxy of lifetime reproductive effort available in the data is used for inference. As expected, the inability to account for measurement error in women's lifetime reproductive effort resulted in the underestimation of its underlying effect size on post-reproductive survival. This article emphasizes the advantages that the SEM framework can provide in handling measurement error via multiple-indicator latent variables in human life history studies. © 2017 Wiley Periodicals, Inc.

Marine Environmental History

DEFF Research Database (Denmark)

Poulsen, Bo

2012-01-01

human society and natural marine resources. Within this broad topic, several trends and objectives are discernable. The essay argue that the so-called material marine environmental history has its main focus on trying to reconstruct the presence, development and environmental impact of past fisheries......This essay provides an overview of recent trends in the historiography of marine environmental history, a sub-field of environmental history which has grown tremendously in scope and size over the last c. 15 years. The object of marine environmental history is the changing relationship between...... and whaling operations. This ambition often entails a reconstruction also of how marine life has changed over time. The time frame rages from Paleolithicum to the present era. The field of marine environmental history also includes a more culturally oriented environmental history, which mainly has come...

Family history of alcoholism and the human brain response to oral sucrose

Directory of Open Access Journals (Sweden)

William J.A. Eiler, II

2018-01-01

Full Text Available A heightened hedonic response to sweet tastes has been associated with increased alcohol preference and alcohol consumption in both humans and animals. The principal goal of this study was to examine blood oxygenation level dependent (BOLD activation to high- and low-concentration sweet solutions in subjects who are either positive (FHP or negative (FHN for a family history of alcoholism. Seventy-four non-treatment seeking, community-recruited, healthy volunteers (22.8 ± 1.6 SD years; 43% men rated a range of sucrose concentrations in a taste test and underwent functional magnetic resonance imaging (fMRI during oral delivery of water, 0.83 M, and 0.10 M sucrose. Sucrose compared to water produced robust activation in primary gustatory cortex, ventral insula, amygdala, and ventral striatum. FHP subjects displayed greater bilateral amygdala activation than FHN subjects in the low sucrose concentration (0.10 M. In secondary analyses, the right amygdala response to the 0.10 M sucrose was greatest in FHP women. When accounting for group differences in drinks per week, the family history groups remained significantly different in their right amygdala response to 0.10 M sucrose. Our findings suggest that the brain response to oral sucrose differs with a family history of alcoholism, and that this response to a mildly reinforcing primary reward might be an endophenotypic marker of alcoholism risk.

Fast-slow continuum and reproductive strategies structure plant life-history variation worldwide

DEFF Research Database (Denmark)

Salguero-Gómez, Roberto; Jones, Owen R; Jongejans, Eelke

2016-01-01

The identification of patterns in life-history strategies across the tree of life is essential to our prediction of population persistence, extinction, and diversification. Plants exhibit a wide range of patterns of longevity, growth, and reproduction, but the general determinants of this enormous...... variation in life history are poorly understood. We use demographic data from 418 plant species in the wild, from annual herbs to supercentennial trees, to examine how growth form, habitat, and phylogenetic relationships structure plant life histories and to develop a framework to predict population...

Evolution of life history and behavior in Hominidae: towards phylogenetic reconstruction of the chimpanzee-human last common ancestor.

Science.gov (United States)

Duda, Pavel; Zrzavý, Jan

2013-10-01

The origin of the fundamental behavioral differences between humans and our closest living relatives is one of the central issues of evolutionary anthropology. The prominent, chimpanzee-based referential model of early hominin behavior has recently been challenged on the basis of broad multispecies comparisons and newly discovered fossil evidence. Here, we argue that while behavioral data on extant great apes are extremely relevant for reconstruction of ancestral behaviors, these behaviors should be reconstructed trait by trait using formal phylogenetic methods. Using the widely accepted hominoid phylogenetic tree, we perform a series of character optimization analyses using 65 selected life-history and behavioral characters for all extant hominid species. This analysis allows us to reconstruct the character states of the last common ancestors of Hominoidea, Hominidae, and the chimpanzee-human last common ancestor. Our analyses demonstrate that many fundamental behavioral and life-history attributes of hominids (including humans) are evidently ancient and likely inherited from the common ancestor of all hominids. However, numerous behaviors present in extant great apes represent their own terminal autapomorphies (both uniquely derived and homoplastic). Any evolutionary model that uses a single extant species to explain behavioral evolution of early hominins is therefore of limited use. In contrast, phylogenetic reconstruction of ancestral states is able to provide a detailed suite of behavioral, ecological and life-history characters for each hypothetical ancestor. The living great apes therefore play an important role for the confident identification of the traits found in the chimpanzee-human last common ancestor, some of which are likely to represent behaviors of the fossil hominins. Copyright © 2013 Elsevier Ltd. All rights reserved.

A demographic history of a population of howler monkeys (Alouatta palliata living in a fragmented landscape in Mexico

Directory of Open Access Journals (Sweden)

Jurgi Cristóbal Azkarate

2017-08-01

Full Text Available Long-term field studies are critical for our understanding of animal life history and the processes driving changes in demography. Here, we present long-term demographic data for the northernmost population of mantled howler monkeys (Alouatta palliata residing in a highly anthropogenically fragmented landscape in Los Tuxtlas, Mexico. We carried out 454 monthly group visits to 10 groups of mantled howler monkeys between 2000 and 2011. The population remained relatively stable over the 11-year study period, with an overall increase in the total number of individuals. Birth rates and inter-birth intervals were comparable to those of howler monkeys at non-fragmented sites, suggesting that living in a fragmented landscape did not affect the reproductive output of our study population. Moreover, despite the landscape, dispersal events were commonplace, including many secondary dispersals (individuals emigrating from groups that they had previously immigrated into. Finally, we found a marked effect of seasonality on the dynamics of our study population. In particular, the period of lowest temperatures and resource scarcity between November and March was associated with higher mortality and reproductive inhibition, while the period of resource abundance between April and May was associated with the majority of conceptions and weaning of offspring. This, in turn, could be influencing dispersal patterns in our study area, as male howler monkeys seem to time some of their immigrations into new groups to coincide with the start of the period of higher fertility, while females preferentially joined new groups several months before the onset of this period. These data have important implications for the conservation and management of howler monkeys in fragmented landscapes, as well as for our understanding of the effect of seasonality over howler monkey dispersal, reproduction and survival.

Future scenarios for energy consumption and carbon emissions due to demographic transitions in Chinese households

Science.gov (United States)

Yu, Biying; Wei, Yi-Ming; Kei, Gomi; Matsuoka, Yuzuru

2018-02-01

Population dynamics has been acknowledged as a key concern for projecting future emissions, partly because of the huge uncertainties related to human behaviour. However, the heterogeneous shifts of human behaviour in the process of demographic transition are not well explored when scrutinizing the impacts of population dynamics on carbon emissions. Here, we expand the existing population-economy-environment analytical structure to address the above limitations by representing the trend of demographic transitions to small-family and ageing society. We specifically accommodate for inter- and intra-life-stage variations in time allocation and consumption in the population rather than assuming a representative household, and take a less developed province, Sichuan, in China as the empirical context. Our results show that the demographic shift to small and ageing households will boost energy consumption and carbon emissions, driven by the joint variations in time-use and consumption patterns. Furthermore, biased pictures of changing emissions will emerge if the time effect is disregarded.

Community College Students with Criminal Justice Histories and Human Services Education: Glass Ceiling, Brick Wall, or a Pathway to Success

Science.gov (United States)

Rose, Lisa Hale

2015-01-01

In spite of open access to community college education, specifically human service associate degree programs, students with criminal justice histories do not necessarily have an unobstructed pathway to obtaining the degree and admission to the baccalaureate programs in human services and social work that are almost always selective. The first…

Francis Bacon's natural history and civil history: a comparative survey.

Science.gov (United States)

Manzo, Silvia

2012-01-01

The aim of this paper is to offer a comparative survey of Bacon's theory and practice of natural history and of civil history, particularly centered on their relationship to natural philosophy and human philosophy. I will try to show that the obvious differences concerning their subject matter encompass a number of less obvious methodological and philosophical assumptions which reveal a significant practical and conceptual convergence of the two fields. Causes or axioms are prescribed as the theoretical end-products of natural history, whereas precepts are envisaged as the speculative outcomes derived from perfect civil history. In spite of this difference, causes and precepts are thought to enable effective action in order to change the state of nature and of man, respectively. For that reason a number of common patterns are to be found in Bacon's theory and practice of natural and civil history.

Comparing Machine Learning Classifiers and Linear/Logistic Regression to Explore the Relationship between Hand Dimensions and Demographic Characteristics.

Science.gov (United States)

Miguel-Hurtado, Oscar; Guest, Richard; Stevenage, Sarah V; Neil, Greg J; Black, Sue

2016-01-01

Understanding the relationship between physiological measurements from human subjects and their demographic data is important within both the biometric and forensic domains. In this paper we explore the relationship between measurements of the human hand and a range of demographic features. We assess the ability of linear regression and machine learning classifiers to predict demographics from hand features, thereby providing evidence on both the strength of relationship and the key features underpinning this relationship. Our results show that we are able to predict sex, height, weight and foot size accurately within various data-range bin sizes, with machine learning classification algorithms out-performing linear regression in most situations. In addition, we identify the features used to provide these relationships applicable across multiple applications.

The Natural History and Risk Factors of Musculoskeletal Conditions Resulting in Disability Among US Army Personnel

National Research Council Canada - National Science Library

Lincoln, Andrew

2002-01-01

We describe the natural history of 13 musculoskeletal conditions requiring hospitalization and identify demographic, behavioral, psychosocial, occupational, and clinical characteristics most strongly...

Trehalose : a review of properties, history of use and human tolerance, and results of multiple safety studies

NARCIS (Netherlands)

Richards, A.B.; Krakowka, S.; Dexter, L.B.; Schmid, H.; Wolterbeek, A.P.M.; Waalkens-Berendsen, D.H.; Shigoyuki, A.; Kurimoto, M.

2002-01-01

This paper contains a review of the history, natural occurrence, human consumption, metabolism, manufacture, and the results of eight standardized animal safety studies using trehalose. Trehalose (α,α-trehalose) is a naturally occurring sugar containing two D-glucose units in an α,α-1,1 linkage.

Differences in demographic traits of four butterflyfish species between two reefs of the Great Barrier Reef separated by 1,200 km

KAUST Repository

Berumen, Michael L.

2011-11-16

Many species demonstrate variation in life history attributes in response to gradients in environmental conditions. For fishes, major drivers of life history variation are changes in temperature and food availability. This study examined large-scale variation in the demography of four species of butterflyfishes (Chaetodon citrinellus, Chaetodon lunulatus, Chaetodon melannotus, and Chaetodon trifascialis) between two locations on Australia\\'s Great Barrier Reef (Lizard Island and One Tree Island, separated by approximately 1,200 km). Variation in age-based demographic parameters was assessed using the re-parameterised von Bertalanffy growth function. All species displayed measurable differences in body size between locations, with individuals achieving a larger adult size at the higher latitude site (One Tree Island) for three of the four species examined. Resources and abundances of the study species were also measured, revealing some significant differences between locations. For example, for C. trifascialis, there was no difference in its preferred resource or in abundance between locations, yet it achieved a larger body size at the higher latitude location, suggesting a response to temperature. For some species, resources and abundances did vary between locations, limiting the ability to distinguish between a demographic response to temperature as opposed to a response to food or competition. Future studies of life histories and demographics at large spatial scales will need to consider the potentially confounding roles of temperature, resource usage and availability, and abundance/competition to disentangle the effects of these environmental variables. © 2011 Springer-Verlag.

The influence of life history and sexual dimorphism on entheseal changes in modern humans and African great apes.

Directory of Open Access Journals (Sweden)

Marco Milella

Full Text Available Entheseal changes have been widely studied with regard to their correlation to biomechanical stress and their usefulness for biocultural reconstructions. However, anthropological and medical studies have demonstrated the marked influence of both age and sex on the development of these features. Studies of entheseal changes are mostly aimed in testing functional hypotheses and are mostly focused on modern humans, with few data available for non-human primates. The lack of comparative studies on the effect of age and sex on entheseal changes represent a gap in our understanding of the evolutionary basis of both development and degeneration of the human musculoskeletal system. The aim of the present work is to compare age trajectories and patterns of sexual dimorphism in entheseal changes between modern humans and African great apes. To this end we analyzed 23 postcranial entheses in a human contemporary identified skeletal collection (N = 484 and compared the results with those obtained from the analysis of Pan (N = 50 and Gorilla (N = 47 skeletal specimens. Results highlight taxon-specific age trajectories possibly linked to differences in life history schedules and phyletic relationships. Robusticity trajectories separate Pan and modern humans from Gorilla, whereas enthesopathic patterns are unique in modern humans and possibly linked to their extended potential lifespan. Comparisons between sexes evidence a decreasing dimorphism in robusticity from Gorilla, to modern humans to Pan, which is likely linked to the role played by size, lifespan and physical activity on robusticity development. The present study confirms previous hypotheses on the possible relevance of EC in the study of life history, pointing moreover to their usefulness in evolutionary studies.

77 FR 42510 - Notice of Inventory Completion: History Colorado, Denver, CO

Science.gov (United States)

2012-07-19

... associated funerary objects may contact History Colorado. Disposition of the human remains and associated... human remains and associated funerary objects under the control of History Colorado, Denver, CO. One set... detailed assessment of the human remains and associated funerary objects was made by History Colorado...

Material Stock Demographics: Cars in Great Britain.

Science.gov (United States)

Cabrera Serrenho, André; Allwood, Julian M

2016-03-15

Recent literature on material flow analysis has been focused on quantitative characterization of past material flows. Fewer analyses exist on past and prospective quantification of stocks of materials in-use. Some of these analyses explore the composition of products' stocks, but a focus on the characterization of material stocks and its relation with service delivery is often neglected. We propose the use of the methods of human demography to characterize material stocks, defined herein as stock demographics, exploring the insights that this approach could provide for the sustainable management of materials. We exemplify an application of stock demographics by characterizing the composition and service delivery of iron, steel, and aluminum stocks of cars in Great Britain, 2002-2012. The results show that in this period the stock has become heavier, it is traveling less, and it is idle for more time. The visualization of material stocks' dynamics demonstrates the pace of product replacement as a function of its usefulness and enables the formulation of policy interventions and the exploration of future trends.

从环境的历史到环境史——关于环境史研究的一种认识%From the history of the environment to environmental history: A personal understanding of environmental history studies

Institute of Scientific and Technical Information of China (English)

梅雪芹

2007-01-01

By and large, there are three kinds of research on environment: the history of environment as a field of natural history studies, the history of environment as within the scope of history of society studies, and environmental history as the study of the relationship between human and nature. The methodological perspective of the relationship between humanity and environmental distinguishes the third from the previous two. From thi sperspective, when we probe the mutual effects between human and nature, we will stress on their interactions. The new era and the realities of contemporary society foster the rise of environmental history, which has not only theoretical values but also practical significance.

The impact of selection, gene flow and demographic history on heterogeneous genomic divergence: three-spine sticklebacks in divergent environments.

Science.gov (United States)

Ferchaud, Anne-Laure; Hansen, Michael M

2016-01-01

Heterogeneous genomic divergence between populations may reflect selection, but should also be seen in conjunction with gene flow and drift, particularly population bottlenecks. Marine and freshwater three-spine stickleback (Gasterosteus aculeatus) populations often exhibit different lateral armour plate morphs. Moreover, strikingly parallel genomic footprints across different marine-freshwater population pairs are interpreted as parallel evolution and gene reuse. Nevertheless, in some geographic regions like the North Sea and Baltic Sea, different patterns are observed. Freshwater populations in coastal regions are often dominated by marine morphs, suggesting that gene flow overwhelms selection, and genomic parallelism may also be less pronounced. We used RAD sequencing for analysing 28 888 SNPs in two marine and seven freshwater populations in Denmark, Europe. Freshwater populations represented a variety of environments: river populations accessible to gene flow from marine sticklebacks and large and small isolated lakes with and without fish predators. Sticklebacks in an accessible river environment showed minimal morphological and genomewide divergence from marine populations, supporting the hypothesis of gene flow overriding selection. Allele frequency spectra suggested bottlenecks in all freshwater populations, and particularly two small lake populations. However, genomic footprints ascribed to selection could nevertheless be identified. No genomic regions were consistent freshwater-marine outliers, and parallelism was much lower than in other comparable studies. Two genomic regions previously described to be under divergent selection in freshwater and marine populations were outliers between different freshwater populations. We ascribe these patterns to stronger environmental heterogeneity among freshwater populations in our study as compared to most other studies, although the demographic history involving bottlenecks should also be considered in the

Why do women stop reproducing before menopause? A life-history approach to age at last birth.

Science.gov (United States)

Towner, Mary C; Nenko, Ilona; Walton, Savannah E

2016-04-19

Evolutionary biologists have long considered menopause to be a fundamental puzzle in understanding human fertility behaviour, as post-menopausal women are no longer physiologically capable of direct reproduction. Menopause typically occurs between 45 and 55 years of age, but across cultures and history, women often stop reproducing many years before menopause. Unlike age at first reproduction or even birth spacing, a woman nearing the end of her reproductive cycle is able to reflect upon the offspring she already has--their numbers and phenotypic qualities, including sexes. This paper reviews demographic data on age at last birth both across and within societies, and also presents a case study of age at last birth in rural Bangladeshi women. In this Bangladeshi sample, age at last birth preceded age at menopause by an average of 11 years, with marked variation around that mean, even during a period of high fertility. Moreover, age at last birth was not strongly related to age at menopause. Our literature review and case study provide evidence that stopping behaviour needs to be more closely examined as an important part of human reproductive strategies and life-history theory. Menopause may be a final marker of permanent reproductive cessation, but it is only one piece of the evolutionary puzzle. © 2016 The Author(s).

Sustainability or collapse: What can we learn from integrating the history of humans and the rest of nature?

NARCIS (Netherlands)

Costanza, R.; Graumlich, L.; Steffen, W.; Crumley, C.; Dearing, J.; Hibbard, K.; Leemans, R.; Redman, C.; Schimel, D.

2007-01-01

Understanding the history of how humans have interacted with the rest of nature can help clarify the options for managing our increasingly interconnected global system. Simple, deterministic relationships between environmental stress and social change are inadequate. Extreme drought, for instance,

Demographic features of subjects with congenital glaucoma

Science.gov (United States)

Tamçelik, Nevbahar; Atalay, Eray; Bolukbasi, Selim; Çapar, Olgu; Ozkok, Ahmet

2014-01-01

Context: Congenital glaucoma is a potentially blinding ocular disease of the childhood. Identification of the possible associated risk factors and may be helpful for prevention or early detection of this public health problem. Aims: To demonstrate the demographic features of congenital glaucoma subjects. Setting and Design: The charts of congenital glaucoma patients referred to Tamcelik Glaucoma Center were retrospectively reviewed through the dates of 2000 and 2013. Materials and Methods: Analyzed data included diagnosis, age at first presentation, symptoms at first presentation, laterality of the disease, sex, presence of consanguinity, family history of congenital glaucoma, maturity of the fetus at delivery, and maternal age at conception. Statistical Analysis Used: Statistical Package for Social Sciences (SPSS) version 19.0 by IBM (SPSS Inc, Chicago, Illinois, USA) was used to compare the mean of continuous variables with Student's t-test and analysis of variance (ANOVA) and χ2 test was used to test differences in proportions of categorical variables. Results: The data of 600 eyes of 311 patients were analyzed. The distribution of primary and secondary congenital glaucoma among the patients were 63.3% (n = 197) and 36.7% (n = 114), respectively. Of the 311 patients, 57.2% (n = 178) were male and 42.8% (n = 133) were female. The overall frequency of bilateral disease was 92.3% (n = 287). Overall rate of consanguinity and positive family history was 45.3% (n = 141) and 21.2% (n = 66), respectively. Conclusions: Bilateral disease in this study was more common than previously reported studies. Positive family history was more frequent in primary congenital glaucoma although not statistically significant. PMID:24881602

HLA DNA sequence variation among human populations: molecular signatures of demographic and selective events.

Directory of Open Access Journals (Sweden)

Stéphane Buhler

2011-02-01

to explore the genetic history of human populations, and that their analysis allows a more thorough investigation of human MHC molecular evolution.

Enforcement and Compliance History Online | US EPA

Science.gov (United States)

ECHO, Enforcement and Compliance History Online, provides compliance and enforcement information for approximately 800,000 EPA-regulated facilities nationwide. ECHO includes permit, inspection, violation, enforcement action, and penalty information about facilities regulated under the Clean Air Act (CAA) Stationary Source Program, Clean Water Act (CWA) National Pollutant Elimination Discharge System (NPDES), and/or Resource Conservation and Recovery Act (RCRA). Information also is provided on surrounding demographics when available.

Genomic validation of the differential preservation of population history in modern human cranial anatomy.

Science.gov (United States)

Reyes-Centeno, Hugo; Ghirotto, Silvia; Harvati, Katerina

2017-01-01

In modern humans, the significant correlation between neutral genetic loci and cranial anatomy suggests that the cranium preserves a population history signature. However, there is disagreement on whether certain parts of the cranium preserve this signature to a greater degree than other parts. It is also unclear how different quantitative measures of phenotype affect the association of genetic variation and anatomy. Here, we revisit these matters by testing the correlation of genetic distances and various phenotypic distances for ten modern human populations. Geometric morphometric shape data from the crania of adult individuals (n = 224) are used to calculate phenotypic P ST , Procrustes, and Mahalanobis distances. We calculate their correlation to neutral genetic distances, F ST , derived from single nucleotide polymorphisms (SNPs). We subset the cranial data into landmark configurations that include the neurocranium, the face, and the temporal bone in order to evaluate whether these cranial regions are differentially correlated to neutral genetic variation. Our results show that P ST , Mahalanobis, and Procrustes distances are correlated with F ST distances to varying degrees. They indicate that overall cranial shape is significantly correlated with neutral genetic variation. Of the component parts examined, P ST distances for both the temporal bone and the face have a stronger association with F ST distances than the neurocranium. When controlling for population divergence time, only the whole cranium and the temporal bone have a statistically significant association with F ST distances. Our results confirm that the cranium, as a whole, and the temporal bone can be used to reconstruct modern human population history. © 2016 Wiley Periodicals, Inc.

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

Science.gov (United States)

Alonso, Santos; Armour, John A. L.

2001-01-01

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

Socio-economic and demographic determinants of Human ...

African Journals Online (AJOL)

Approaches to reduce related morbidity and mortality include screening for cervical cancer and administration of Human Papilloma Virus (HPV) vaccine to HPV non-infected females to trigger host resistance. The uptake of HPV vaccine globally has been reported to be less than 1%. Objectives: To assess the level and ...

EDUCATION, WORK AND THEIR RELATIONS THROUGHOUT HISTORY OF HUMANITY IN DIFFERENT MODES OF PRODUCTION OF EXISTENCE

Directory of Open Access Journals (Sweden)

Denize Cristina Kaminski Ferreira

2011-12-01

Full Text Available The present article has as objective to analyze the relation between education and work throughout the history of the humanity, for in such a way, the starting point is the conceptualization of the related categories, as well as the exposition of its variations and relation in the different ways of material production of the existence human being (primitive community, slavery society, feudal system and capitalism, aiming at to apprehend the multiple influences that both exert between itself, in order to make possible a bigger understanding of the historical and social evolution of the man

Life history strategy of the honey bee, Apis mellifera.

Science.gov (United States)

Seeley, Thomas D

1978-01-01

The feral honey bee queens (colonies) of central New York State (USA) show a K-type life history strategy. Their demographic characteristics include low early life mortality, low reproductive rate, long lifespan, high population stability and repeated reproductions. Identifying the life history strategy of these bees reveals the general pattern of selection for competitive ability, rather than productivity, which has shaped their societies. Selection for competitive power explains the adaptiveness (compared with alternatives found in many other insect societies) of the large perennial colonies, infrequent but expensive offspring, and efficient foraging which characterize the social organization of these bees.

Genome sequence, population history, and pelage genetics of the endangered African wild dog (Lycaon pictus).

Science.gov (United States)

Campana, Michael G; Parker, Lillian D; Hawkins, Melissa T R; Young, Hillary S; Helgen, Kristofer M; Szykman Gunther, Micaela; Woodroffe, Rosie; Maldonado, Jesús E; Fleischer, Robert C

2016-12-09

The African wild dog (Lycaon pictus) is an endangered African canid threatened by severe habitat fragmentation, human-wildlife conflict, and infectious disease. A highly specialized carnivore, it is distinguished by its social structure, dental morphology, absence of dewclaws, and colorful pelage. We sequenced the genomes of two individuals from populations representing two distinct ecological histories (Laikipia County, Kenya and KwaZulu-Natal Province, South Africa). We reconstructed population demographic histories for the two individuals and scanned the genomes for evidence of selection. We show that the African wild dog has undergone at least two effective population size reductions in the last 1,000,000 years. We found evidence of Lycaon individual-specific regions of low diversity, suggestive of inbreeding or population-specific selection. Further research is needed to clarify whether these population reductions and low diversity regions are characteristic of the species as a whole. We documented positive selection on the Lycaon mitochondrial genome. Finally, we identified several candidate genes (ASIP, MITF, MLPH, PMEL) that may play a role in the characteristic Lycaon pelage.

Humans and viticulture in Sardinia: the history and social relations as signs of identity of the wine-growing area

OpenAIRE

Benedetto, Graziella; Carboni, Donatella; Corinto, Gian Luigi

2014-01-01

The premise of this paper is that viticulture is an expression of history and social relations. In this sense, we embrace a post-modern vision of development that characterized both economic and cultural geography and agricultural economics. Such an approach does consider culture as an element of mediation between humans and the nature, placing it at the heart of the wine-growing territory. So history and social relations have influenced the today spatial densification by types of grape and t...

77 FR 13629 - Notice of Inventory Completion: History Colorado, Denver, CO

Science.gov (United States)

2012-03-07

... Fort Hall Reservation of Idaho; and the Zuni Tribe of the Zuni Reservation, New Mexico. History and...: History Colorado, Denver, CO AGENCY: National Park Service, Interior. ACTION: Notice. SUMMARY: History... human remains may contact History Colorado. Disposition of the human remains to the Indian tribes stated...

Sapiens a brief history of humankind

CERN Document Server

Harari, Yuval Noah

2015-01-01

From a renowned historian comes a groundbreaking narrative of humanity’s creation and evolution—a #1 international bestseller—that explores the ways in which biology and history have defined us and enhanced our understanding of what it means to be “human.” One hundred thousand years ago, at least six different species of humans inhabited Earth. Yet today there is only one—homo sapiens. What happened to the others? And what may happen to us? Most books about the history of humanity pursue either a historical or a biological approach, but Dr. Yuval Noah Harari breaks the mold with this highly original book that begins about 70,000 years ago with the appearance of modern cognition. From examining the role evolving humans have played in the global ecosystem to charting the rise of empires, Sapiens integrates history and science to reconsider accepted narratives, connect past developments with contemporary concerns, and examine specific events within the context of larger ideas. Dr. Harari also comp...

Serbian demographers on demography

Directory of Open Access Journals (Sweden)

Rašević Mirjana

2013-01-01

Full Text Available Introduction: The objective of this paper is to collect the opinions of the leading demographers in Serbia on four significant matters. The matters are: development, state and future of demography, the successfulness of researchers in this scientific discipline, improvement of the Stanovništvo journal, as well as the population priority of our society and range of population policies. Method: A qualitative interview was chosen as the instrument for data collection. Namely, a structured interview, based on nine questions was sent by e-mail to eleven addresses of relevant demographers in the second half of October 2013. The basic reason for sending questions by e-mail was the aspiration to obtain authentic replies which require time for contemplation. Ten completed questionnaires were returned within two weeks. On the one hand, an integral picture on the chosen themes for research was attempted to be obtained in the analysis of received opinions to certain groups of questions and on the other hand to portray the spectrum of different observations. The responses of our prominent demographers were analyzed and compared to clearly pronounced standpoints of eminent demographers published in world journals on similar themes and with findings of internet researches among members of the International Union for the Scientific Study of Population. Results: The results show that there is a high level of consent among demographers in Serbia regarding the well positioning of demography in relation to other social studies and its good perspectives. The interviewed experts see the future of demography in its integration with a wide circle of sciences, the application of demography and/or greater engagement of researchers in carrying out public policies. However, the estimations of the interviewed demographers as regards the development and state of demography in Serbia are divided. Although a large number of topics had been listed, migrations and population

Clinical and Demographical Characteristics of Patients with Medication Overuse Headache in Argentina and Chile

DEFF Research Database (Denmark)

Shand, Beatriz; Goicochea, Maria Teresa; Valenzuela, Raul

2015-01-01

population was formed by 240 MOH subjects, 110 from Chile and 130 from Argentina, consecutively attending the local headache centres. In each centre, specifically trained neurologist interviewed and confirmed the diagnosis according to the ICHD-II criteria. A detailed history was collected on an electronic......BACKGROUND: Data on the characteristics of Medication Overuse Headache (MOH) in Latin American (LA) are scarce. Here we report the demographic and clinical features of the MOH patients from Argentina and Chile enrolled in the multinational COMOESTAS project in the period 2008-2010. METHODS: The LA......, where it affects mostly women, in the most active decades of life. Some differences emerge as regards the demographic and clinical characteristics of MOH in this population as compared to Europe or Northern America. What seems more worrying about MOH in Argentina and Chile is that most patients overuse...

Human bony labyrinth is an indicator of population history and dispersal from Africa.

Science.gov (United States)

Ponce de León, Marcia S; Koesbardiati, Toetik; Weissmann, John David; Milella, Marco; Reyna-Blanco, Carlos S; Suwa, Gen; Kondo, Osamu; Malaspinas, Anna-Sapfo; White, Tim D; Zollikofer, Christoph P E

2018-04-17

The dispersal of modern humans from Africa is now well documented with genetic data that track population history, as well as gene flow between populations. Phenetic skeletal data, such as cranial and pelvic morphologies, also exhibit a dispersal-from-Africa signal, which, however, tends to be blurred by the effects of local adaptation and in vivo phenotypic plasticity, and that is often deteriorated by postmortem damage to skeletal remains. These complexities raise the question of which skeletal structures most effectively track neutral population history. The cavity system of the inner ear (the so-called bony labyrinth) is a good candidate structure for such analyses. It is already fully formed by birth, which minimizes postnatal phenotypic plasticity, and it is generally well preserved in archaeological samples. Here we use morphometric data of the bony labyrinth to show that it is a surprisingly good marker of the global dispersal of modern humans from Africa. Labyrinthine morphology tracks genetic distances and geography in accordance with an isolation-by-distance model with dispersal from Africa. Our data further indicate that the neutral-like pattern of variation is compatible with stabilizing selection on labyrinth morphology. Given the increasingly important role of the petrous bone for ancient DNA recovery from archaeological specimens, we encourage researchers to acquire 3D morphological data of the inner ear structures before any invasive sampling. Such data will constitute an important archive of phenotypic variation in present and past populations, and will permit individual-based genotype-phenotype comparisons. Copyright © 2018 the Author(s). Published by PNAS.

Environmental History

OpenAIRE

Kearns, Gerard

2004-01-01

There was a time when almost all Western geography could be termed environmental history. In the late nineteenth century, physical geographers explained landscapes by describing how they had evolved. Likewise, human geographers saw society as shaped by the directing hands of the environment. By the 1960s this had very much changed. Process studies shortened the temporal framework in geographical explanation and cut the cord between nature and society. Now, physical and human...

Human heredity after 1945: moving populations centre stage.

Science.gov (United States)

Bangham, Jenny; de Chadarevian, Soraya

2014-09-01

The essays in this issue look at the contested history of human heredity after 1945 from a new analytical angle, that of populations and the ways in which they were constructed and studied. One consequence of this approach is that we do not limit our attention to the disciplinary study of genetics. After the Second World War, populations became a central topic for an array of fields, including demography, anthropology, epidemiology, and public health. Human heredity had a role in all of these: demographers carried out mental surveys in efforts to distinguish hereditary from environmental factors, doctors screened newborns and tested pregnant women for chromosome disorders; anthropologists collected blood from remote locations to gain insights into the evolutionary history of human populations; geneticists monitored people exposed to radiation. Through this work, populations were labelled as clinical, normal, primitive, pure, vulnerable or exotic. We ask: how were populations chosen, who qualified as members, and how was the study of human heredity shaped by technical, institutional and geopolitical conditions? By following the practical and conceptual work to define populations as objects of research, the essays trace the circulation of practices across different fields and contexts, bringing into view new actors, institutions, and geographies. By doing so the collection shows how human heredity research was linked to the broader politics of the postwar world, one profoundly conditioned by Cold War tensions, by nationalist concerns, by colonial and post-colonial struggles, by modernisation projects and by a new internationalism. Copyright © 2014 Elsevier Ltd. All rights reserved.

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

Science.gov (United States)

Mogk, Lylas; Goodrich, Gregory

2004-01-01

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

Volcanoes and human history

Science.gov (United States)

Cashman, K. V.; Giordano, G.

2008-10-01

The study of volcanic hazards leads inevitably to questions of how past cultures have lived in volcanically active regions of the world. Here we summarize linkages between volcanological, archaeological and anthropological studies of historic and prehistoric volcanic eruptions, with the goal of evaluating the impact of past eruptions on human populations to better prepare for future events. We use examples from papers collected in this volume to illustrate ways in which volcanological studies aid archaeological investigations by providing basic stratigraphic markers and information about the nature and timing of specific volcanic events. We then turn to archaeological perspectives, which provide physical evidence of the direct impacts of volcanic eruptions, such as site abandonment and human migration, as well as indirect impacts on local cultures as reflected in human artifacts. Finally we review anthropological studies of societal responses to past and recent volcanic eruptions. We pay particular attention to both the psychological impact of catastrophic events and records of these impacts encoded within oral traditions. Taken together these studies record drastic short-term eruption impacts but adaptation to volcanic activity over the longer term, largely through strategies of adaptive land use.

Inferring contemporary levels of gene flow and demographic history in a local population of the leaf beetle Gonioctena olivacea from mitochondrial DNA sequence variation.

Science.gov (United States)

Mardulyn, Patrick; Milinkovitch, Michel C

2005-05-01

We have studied mitochondrial DNA variation in a local population of the leaf beetle species Gonioctena olivacea, to check whether its apparent low dispersal behaviour affects its pattern of genetic variation at a small geographical scale. We have sampled 10 populations of G. olivacea within a rectangle of 5 x 2 km in the Belgian Ardennes, as well as five populations located approximately along a straight line of 30 km and separated by distances of 3-12 km. For each sampled individual (8-19 per population), a fragment of the mtDNA control region was polymerase chain reaction-amplified and sequenced. Sequence data were analysed to test whether significant genetic differentiation could be detected among populations separated by such relatively short distances. The reconstructed genealogy of the mitochondrial haplotypes was also used to investigate the demographic history of these populations. Computer simulations of the evolution of populations were conducted to assess the minimum amount of gene flow that is necessary to explain the observed pattern of variation in the samples. Results show that migration among populations included in the rectangle of 5 x 2 km is substantial, and probably involves the occurrence of dispersal flights. This appears difficult to reconcile with the results of a previous ecological field study that concluded that most of this species dispersal occurs by walking. While sufficient migration to homogenize genetic diversity occurs among populations separated by distances of a few hundred metres to a few kilometres, distances greater than 5 km results in contrast in strong differentiation among populations, suggesting that migration is drastically reduced on such distances. Finally, the results of coalescent simulations suggest that the star-like genealogy inferred from the mtDNA sequence data is fully compatible with a past demographic expansion. However, a metapopulation structure alone (without the need to invoke a population expansion

Patterns of demographic change in the Americas.

Science.gov (United States)

Ubelaker, D H

1992-06-01

Considerable scholarly debate has focused on the nature of demographic change in the Americas before and after 1492. Recent research on human skeletal samples and related archeological materials suggests that morbidity and mortality were increasing throughout much of the Western Hemisphere before 1492 in response to increased population density, increased sedentism, and changing subsistence. The evidence suggests that after 1492 population reduction was caused not by continental pandemics but by localized or regional epidemics augmented by social and economic disruption. The twentieth century has witnessed remarkable Native American population recovery, fueled both by improvements in health care and changing definitions of "being Indian."

Demographic Consequences of Defeating Aging

OpenAIRE

Gavrilov, Leonid A.; Gavrilova, Natalia S.

2010-01-01

A common objection against starting a large-scale biomedical war on aging is the fear of catastrophic population consequences (overpopulation). This fear is only exacerbated by the fact that no detailed demographic projections for radical life extension scenario have been conducted so far. This study explores different demographic scenarios and population projections, in order to clarify what could be the demographic consequences of a successful biomedical war on aging. A general conclusion o...

Demographic structure and macroeconomic trends

OpenAIRE

Aksoy, Yunus; Basso, H.S.; Smith, Ronald; Grasl, Tobias

2018-01-01

We estimate the effect of changes in demographic structure on long term\\ud trends of key macroeconomic variables using a Panel VAR for 21 OECD economies from 1970-2014. The panel data variation assists the identification of demographic effects, while the dynamic structure,\\ud incorporating multiple channels of influence, uncovers long-term effects.\\ud We propose a theoretical model, relating demographics, innovation and\\ud growth, whose simulations match our empirical findings. The current\\ud...

Using Twitter for Demographic and Social Science Research: Tools for Data Collection and Processing.

Science.gov (United States)

McCormick, Tyler H; Lee, Hedwig; Cesare, Nina; Shojaie, Ali; Spiro, Emma S

2017-08-01

Despite recent and growing interest in using Twitter to examine human behavior and attitudes, there is still significant room for growth regarding the ability to leverage Twitter data for social science research. In particular, gleaning demographic information about Twitter users-a key component of much social science research-remains a challenge. This article develops an accurate and reliable data processing approach for social science researchers interested in using Twitter data to examine behaviors and attitudes, as well as the demographic characteristics of the populations expressing or engaging in them. Using information gathered from Twitter users who state an intention to not vote in the 2012 presidential election, we describe and evaluate a method for processing data to retrieve demographic information reported by users that is not encoded as text (e.g., details of images) and evaluate the reliability of these techniques. We end by assessing the challenges of this data collection strategy and discussing how large-scale social media data may benefit demographic researchers.

The population genomic landscape of human genetic structure, admixture history and local adaptation in Peninsular Malaysia.

Science.gov (United States)

Deng, Lian; Hoh, Boon Peng; Lu, Dongsheng; Fu, Ruiqing; Phipps, Maude E; Li, Shilin; Nur-Shafawati, Ab Rajab; Hatin, Wan Isa; Ismail, Endom; Mokhtar, Siti Shuhada; Jin, Li; Zilfalil, Bin Alwi; Marshall, Christian R; Scherer, Stephen W; Al-Mulla, Fahd; Xu, Shuhua

2014-09-01

Peninsular Malaysia is a strategic region which might have played an important role in the initial peopling and subsequent human migrations in Asia. However, the genetic diversity and history of human populations--especially indigenous populations--inhabiting this area remain poorly understood. Here, we conducted a genome-wide study using over 900,000 single nucleotide polymorphisms (SNPs) in four major Malaysian ethnic groups (MEGs; Malay, Proto-Malay, Senoi and Negrito), and made comparisons of 17 world-wide populations. Our data revealed that Peninsular Malaysia has greater genetic diversity corresponding to its role as a contact zone of both early and recent human migrations in Asia. However, each single Orang Asli (indigenous) group was less diverse with a smaller effective population size (N(e)) than a European or an East Asian population, indicating a substantial isolation of some duration for these groups. All four MEGs were genetically more similar to Asian populations than to other continental groups, and the divergence time between MEGs and East Asian populations (12,000--6,000 years ago) was also much shorter than that between East Asians and Europeans. Thus, Malaysian Orang Asli groups, despite their significantly different features, may share a common origin with the other Asian groups. Nevertheless, we identified traces of recent gene flow from non-Asians to MEGs. Finally, natural selection signatures were detected in a batch of genes associated with immune response, human height, skin pigmentation, hair and facial morphology and blood pressure in MEGs. Notable examples include SYN3 which is associated with human height in all Orang Asli groups, a height-related gene (PNPT1) and two blood pressure-related genes (CDH13 and PAX5) in Negritos. We conclude that a long isolation period, subsequent gene flow and local adaptations have jointly shaped the genetic architectures of MEGs, and this study provides insight into the peopling and human migration

Genetic analysis reveals demographic fragmentation of grizzly bears yielding vulnerably small populations.

Science.gov (United States)

Proctor, Michael F; McLellan, Bruce N; Strobeck, Curtis; Barclay, Robert M R

2005-11-22

Ecosystem conservation requires the presence of native carnivores, yet in North America, the distributions of many larger carnivores have contracted. Large carnivores live at low densities and require large areas to thrive at the population level. Therefore, if human-dominated landscapes fragment remaining carnivore populations, small and demographically vulnerable populations may result. Grizzly bear range contraction in the conterminous USA has left four fragmented populations, three of which remain along the Canada-USA border. A tenet of grizzly bear conservation is that the viability of these populations requires demographic linkage (i.e. inter-population movement of both sexes) to Canadian bears. Using individual-based genetic analysis, our results suggest this demographic connection has been severed across their entire range in southern Canada by a highway and associated settlements, limiting female and reducing male movement. Two resulting populations are vulnerably small (bear populations may be more threatened than previously thought and that conservation efforts must expand to include international connectivity management. They also demonstrate the ability of genetic analysis to detect gender-specific demographic population fragmentation in recently disturbed systems, a traditionally intractable yet increasingly important ecological measurement worldwide.

The "History" of Victorian Scientific Naturalism: Huxley, Spencer and the "End" of natural history.

Science.gov (United States)

Lightman, Bernard

2016-08-01

As part of their defence of evolutionary theory, T. H. Huxley and Herbert Spencer argued that natural history was no longer a legitimate scientific discipline. They outlined a secularized concept of life from biology to argue for the validity of naturalism. Despite their support for naturalism, they offered two different responses to the decline of natural history. Whereas Huxley emphasized the creation of a biological discipline, and all that that entailed, Spencer was more concerned with constructing an entire intellectual system based on the idea of evolution. In effect, Spencer wanted to create a new scientific worldview based on evolutionary theory. This had consequences for their understanding of human history, especially of how science had evolved through the ages. It affected their conceptions of human agency, contingency, and directionality in history. Examining Huxley's and Spencer's responses to the "end" of natural history reveals some of the deep divisions within scientific naturalism and the inherent problems of naturalism in general. Whereas Huxley chose to separate the natural and the historical, Spencer opted to fuse them into a single system. Crown Copyright © 2016. Published by Elsevier Ltd. All rights reserved.

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

Science.gov (United States)

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

2015-04-01

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

History of falls, gait, balance, and fall risks in older cancer survivors living in the community.

Science.gov (United States)

Huang, Min H; Shilling, Tracy; Miller, Kara A; Smith, Kristin; LaVictoire, Kayle

2015-01-01

Older cancer survivors may be predisposed to falls because cancer-related sequelae affect virtually all body systems. The use of a history of falls, gait speed, and balance tests to assess fall risks remains to be investigated in this population. This study examined the relationship of previous falls, gait, and balance with falls in community-dwelling older cancer survivors. At the baseline, demographics, health information, and the history of falls in the past year were obtained through interviewing. Participants performed tests including gait speed, Balance Evaluation Systems Test, and short-version of Activities-specific Balance Confidence scale. Falls were tracked by mailing of monthly reports for 6 months. A "faller" was a person with ≥1 fall during follow-up. Univariate analyses, including independent sample t-tests and Fisher's exact tests, compared baseline demographics, gait speed, and balance between fallers and non-fallers. For univariate analyses, Bonferroni correction was applied for multiple comparisons. Baseline variables with Pfalls with age as covariate. Sensitivity and specificity of each predictor of falls in the model were calculated. Significance level for the regression analysis was Pfalls. Baseline demographics, health information, history of falls, gaits speed, and balance tests did not differ significantly between fallers and non-fallers. Forward logistic regression revealed that a history of falls was a significant predictor of falls in the final model (odds ratio =6.81; 95% confidence interval =1.594-29.074) (Pfalls were 74% and 69%, respectively. Current findings suggested that for community-dwelling older cancer survivors with mixed diagnoses, asking about the history of falls may help detect individuals at risk of falling.

EJSCREEN Version 1, Demographic Data

Data.gov (United States)

U.S. Environmental Protection Agency — This map service displays demographic data used in EJSCREEN. All demographic data were derived from American Community Survey 2006-2010 estimates. EJSCREEN is an...

Impacts of biological globalization in the Mediterranean: unveiling the deep history of human-mediated gamebird dispersal.

Science.gov (United States)

Forcina, Giovanni; Guerrini, Monica; van Grouw, Hein; Gupta, Brij K; Panayides, Panicos; Hadjigerou, Pantelis; Al-Sheikhly, Omar F; Awan, Muhammad N; Khan, Aleem A; Zeder, Melinda A; Barbanera, Filippo

2015-03-17

Humans have a long history of moving wildlife that over time has resulted in unprecedented biotic homogenization. It is, as a result, often unclear whether certain taxa are native to a region or naturalized, and how the history of human involvement in species dispersal has shaped present-day biodiversity. Although currently an eastern Palaearctic galliform, the black francolin (Francolinus francolinus) was known to occur in the western Mediterranean from at least the time of Pliny the Elder, if not earlier. During Medieval times and the Renaissance, the black francolin was a courtly gamebird prized not only for its flavor, but also its curative, and even aphrodisiac qualities. There is uncertainty, however, whether this important gamebird was native or introduced to the region and, if the latter, what the source of introduction into the western Mediterranean was. Here we combine historical documentation with a DNA investigation of modern birds and archival (13th-20th century) specimens from across the species' current and historically documented range. Our study proves the black francolin was nonnative to the western Mediterranean, and we document its introduction from the east via several trade routes, some reaching as far as South Asia. This finding provides insight into the reach and scope of long-distance trade routes that serviced the demand of European aristocracy for exotic species as symbols of wealth and prestige, and helps to demonstrate the lasting impact of human-mediated long-distance species dispersal on current day biodiversity.

Impacts of biological globalization in the Mediterranean: Unveiling the deep history of human-mediated gamebird dispersal

Science.gov (United States)

Forcina, Giovanni; Guerrini, Monica; van Grouw, Hein; Gupta, Brij K.; Panayides, Panicos; Hadjigerou, Pantelis; Al-Sheikhly, Omar F.; Awan, Muhammad N.; Khan, Aleem A.; Zeder, Melinda A.; Barbanera, Filippo

2015-01-01

Humans have a long history of moving wildlife that over time has resulted in unprecedented biotic homogenization. It is, as a result, often unclear whether certain taxa are native to a region or naturalized, and how the history of human involvement in species dispersal has shaped present-day biodiversity. Although currently an eastern Palaearctic galliform, the black francolin (Francolinus francolinus) was known to occur in the western Mediterranean from at least the time of Pliny the Elder, if not earlier. During Medieval times and the Renaissance, the black francolin was a courtly gamebird prized not only for its flavor, but also its curative, and even aphrodisiac qualities. There is uncertainty, however, whether this important gamebird was native or introduced to the region and, if the latter, what the source of introduction into the western Mediterranean was. Here we combine historical documentation with a DNA investigation of modern birds and archival (13th–20th century) specimens from across the species’ current and historically documented range. Our study proves the black francolin was nonnative to the western Mediterranean, and we document its introduction from the east via several trade routes, some reaching as far as South Asia. This finding provides insight into the reach and scope of long-distance trade routes that serviced the demand of European aristocracy for exotic species as symbols of wealth and prestige, and helps to demonstrate the lasting impact of human-mediated long-distance species dispersal on current day biodiversity. PMID:25733899

The effects of climate change and land-use change on demographic rates and population viability.

Science.gov (United States)

Selwood, Katherine E; McGeoch, Melodie A; Mac Nally, Ralph

2015-08-01

Understanding the processes that lead to species extinctions is vital for lessening pressures on biodiversity. While species diversity, presence and abundance are most commonly used to measure the effects of human pressures, demographic responses give a more proximal indication of how pressures affect population viability and contribute to extinction risk. We reviewed how demographic rates are affected by the major anthropogenic pressures, changed landscape condition caused by human land use, and climate change. We synthesized the results of 147 empirical studies to compare the relative effect size of climate and landscape condition on birth, death, immigration and emigration rates in plant and animal populations. While changed landscape condition is recognized as the major driver of species declines and losses worldwide, we found that, on average, climate variables had equally strong effects on demographic rates in plant and animal populations. This is significant given that the pressures of climate change will continue to intensify in coming decades. The effects of climate change on some populations may be underestimated because changes in climate conditions during critical windows of species life cycles may have disproportionate effects on demographic rates. The combined pressures of land-use change and climate change may result in species declines and extinctions occurring faster than otherwise predicted, particularly if their effects are multiplicative. © 2014 The Authors. Biological Reviews © 2014 Cambridge Philosophical Society.

Role of stable isotope analyses in reconstructing past life-histories and the provenancing human skeletal remains: a review

Directory of Open Access Journals (Sweden)

Sehrawat Jagmahender Singh

2017-09-01

Full Text Available This article reviews the present scenario of use of stable isotopes (mainly δ13C, δ15N, δ18O, 87Sr to trace past life behaviours like breast feeding and weaning practices, the geographic origin, migration history, paleodiet and subsistence patterns of past populations from the chemical signatures of isotopes imprinted in human skeletal remains. This approach is based on the state that food-web isotopic signatures are seen in the human bones and teeth and such signatures can change parallely with a variety of biogeochemical processes. By measuring δ13C and δ15N isotopic values of subadult tissues of different ages, the level of breast milk ingestion at particular ages and the components of the complementary foods can be assessed. Strontium and oxygen isotopic analyses have been used for determining the geographic origins and reconstructing the way of life of past populations as these isotopes can map the isotopic outline of the area from where the person acquired water and food during initial lifetime. The isotopic values of strontium and oxygen values are considered specific to geographical areas and serve as reliable chemical signatures of migration history of past human populations (local or non-local to the site. Previous isotopic studies show that the subsistence patterns of the past human populations underwent extensive changes from nomadic to complete agricultural dependence strategies. The carbon and nitrogen isotopic values of local fauna of any archaeological site can be used to elucidate the prominence of freshwater resources in the diet of the past human populations found near the site. More extensive research covering isotopic descriptions of various prehistoric, historic and modern populations is needed to explore the role of stable isotope analysis for provenancing human skeletal remains and assessing human migration patterns/routes, geographic origins, paleodiet and subsistence practices of past populations.

Perspectives on Population in AP® Human Geography

Science.gov (United States)

Lu, Max; Keller, Kenneth

2016-01-01

A study of human geography begins with the human population. In fact, demographic topics frequently relate to other units in the AP Human Geography course. The three main concepts elaborated upon in this article are (1) the demographic transition model, (2) Malthusian theory and its critics, and (3) pronatalist and antinatalist policies that might…

From Socialism to Hedge Fund: The Human Element and the New History of Capitalism

Directory of Open Access Journals (Sweden)

David Huyssen

2015-08-01

Full Text Available Alfred Winslow Jones was a socialist who founded the first hedge fund in 1949. He had been U.S. Vice Consul in Berlin from 1931 to 1932, Soviet sympathizer and anti-Nazi spy with dissident German communists, humanitarian observer during the Spanish Civil War, acclaimed sociologist of class, and an editor for Fortune magazine. At every stage of his life, Jones occupied positions of advantage, and his invention of the modern hedge fund has had an outsized impact on global capitalism’s contemporary round of financialization. On its face, then, his life would appear to offer ideal material for a “great-man” biography. Yet this “great man” also wrestled with the continual recognition that structural forces were undermining his fondest hopes for social change. Following Georgi Derluguian, Giovanni Arrighi, and Marc Bloch, this article proposes a world-system biography of Jones as a method better suited for mapping the internal dialectics of twentieth-century capitalism, using Jones as a human connection between cyclical and structural transformations of capitalism, and across changes of phase from financial to material expansion—and back again. On another level, it suggests a theoretical reorientation—toward what Bloch called “the human element”—for studies of capitalism’s cultural and material history. It argues that such a reorientation would hold rewards for the “new history of capitalism” field, which until now has pursued its quarry primarily by tracing the movements of commodities, capital, institutions, and ideas.

Identification of risk factors and demographic features of patients with peri partum cardiomyopathy

International Nuclear Information System (INIS)

Sharieff, S.; Khan, Shah-e-Zaman

2002-01-01

Objective: To describe and identify the demographic features and risk factors for peri partum cardiomyopathy (PPCM). Design: A prospective study: The study was conducted at the department of Adult Cardiology, National Institute of Cardiovascular Diseases (NICVD), Karachi, Pakistan from December 1999 to August 2001. Subjects and Methods: A total of 35 consecutive patients diagnosed to have peri partum cardiomyopathy (PPCM) on echocardiogram were enrolled. Proforma containing demographic characteristics and established risk factors for PPCM was established and filled carefully. The data gathered was analyzed statistically. Results: The mean age at the time of diagnosis was 30.8-6.74 years. Urdu speaking (Mohajir) population was found to be more affected ethnic group (42.9%) Majority of the patients was from lower socio-economic group with poor nutritional status (77%) and multiparous (77.14%). 25.7% had past history of PPCM and 71.4% presented during postpartum period. Mortality at six months was 22.8% while 42.9% had persistent disease and only 34.3% recovered completely. Conclusion: Advanced age, lower economic group with poor nutritional status, multi parity and past history of peri partum cardiomyopathy were identified as risk factors for the development of PPCM, especially among Mohajir population. There was no statistically significant difference between the clinical features and outcome of patients presented first time or with recurrent PPCM. We identified advanced age (>30 years), high LVEDD, and low ejection fraction (EF) at initial presentation as poor prognostic factors. (author)

Trauma history characteristics and subsequent PTSD symptoms in motor vehicle accident victims.

Science.gov (United States)

Irish, Leah; Ostrowski, Sarah A; Fallon, William; Spoonster, Eileen; Dulmen, Manfred van; Sledjeski, Eve M; Delahanty, Douglas L

2008-08-01

The present study examined the relationship between trauma history characteristics (number and type of traumas, age at first trauma, and subjective responses to prior traumas) and the development of posttraumatic stress disorder (PTSD) symptoms following a motor vehicle accident (MVA). One hundred eighty-eight adult MVA victims provided information about prior traumatization and were evaluated for PTSD symptoms 6 weeks and one year following the MVA. Results indicated that after controlling for demographics and depression, prior trauma history characteristics accounted for a small, but significant amount of the variance in PTSD symptoms. Distress from prior trauma and number of types of prior traumas were the most meaningful trauma history predictors. Results encourage further evaluation of trauma history as a multifaceted construct.

Human radiation studies: Remembering the early years. Oral history of Dr. George Voelz, M.D., November 29, 1994

Energy Technology Data Exchange (ETDEWEB)

NONE

1995-05-01

Dr. George Voelz was interviewed by representatives of the US DOE Office of Human Radiation Experiments (OHRE). This oral history covers Dr. Voelz`s research on Manhattan Engineering District plutonium workers, the acute and long term effects of radiation, his inhalation studies, and his activities at the 1961 INL reactor accident (SL-1 Reactor). After a brief biographical sketch, Dr. Voelz his remembrances on tissue studies of plutonium workers, the plutonium injection studies of 1945-1946, the controlled environmental radioiodine tests of 1963-1968, and tracer studies with human volunteers at Los Alamos. Dr. Voelz states his opinions concerning misconceptions about the Los Alamos Human Radiation Experiments.

Human radiation studies: Remembering the early years. Oral history of Dr. George Voelz, M.D., November 29, 1994

International Nuclear Information System (INIS)

1995-05-01

Dr. George Voelz was interviewed by representatives of the US DOE Office of Human Radiation Experiments (OHRE). This oral history covers Dr. Voelz's research on Manhattan Engineering District plutonium workers, the acute and long term effects of radiation, his inhalation studies, and his activities at the 1961 INL reactor accident (SL-1 Reactor). After a brief biographical sketch, Dr. Voelz his remembrances on tissue studies of plutonium workers, the plutonium injection studies of 1945-1946, the controlled environmental radioiodine tests of 1963-1968, and tracer studies with human volunteers at Los Alamos. Dr. Voelz states his opinions concerning misconceptions about the Los Alamos Human Radiation Experiments

From Demographic Dividend to Demographic Burden? : Regional Trends of Population Aging in Russia

OpenAIRE

Matytsin, Mikhail; Moorty, Lalita; Richter, Kaspar

2015-01-01

Do regions with higher working age populations grow faster? This paper examines this question using data from Russian regions and finds evidence that demographic trends influence regional growth convergence. In other words, keeping other factors constant, poorer regions grow faster than richer regions, and some of the growth convergence is explained by demographic changes: faster growth in...

How Life History Can Sway the Fixation Probability of Mutants

Science.gov (United States)

Li, Xiang-Yi; Kurokawa, Shun; Giaimo, Stefano; Traulsen, Arne

2016-01-01

In this work, we study the effects of demographic structure on evolutionary dynamics when selection acts on reproduction, survival, or both. In contrast to the previously discovered pattern that the fixation probability of a neutral mutant decreases while the population becomes younger, we show that a mutant with a constant selective advantage may have a maximum or a minimum of the fixation probability in populations with an intermediate fraction of young individuals. This highlights the importance of life history and demographic structure in studying evolutionary dynamics. We also illustrate the fundamental differences between selection on reproduction and selection on survival when age structure is present. In addition, we evaluate the relative importance of size and structure of the population in determining the fixation probability of the mutant. Our work lays the foundation for also studying density- and frequency-dependent effects in populations when demographic structures cannot be neglected. PMID:27129737

The peopling of the African continent and the diaspora into the new world.

Science.gov (United States)

Campbell, Michael C; Hirbo, Jibril B; Townsend, Jeffrey P; Tishkoff, Sarah A

2014-12-01

Africa is the birthplace of anatomically modern humans, and is the geographic origin of human migration across the globe within the last 100,000 years. The history of African populations has consisted of a number of demographic events that have influenced patterns of genetic and phenotypic variation across the continent. With the increasing amount of genomic data and corresponding developments in computational methods, researchers are able to explore long-standing evolutionary questions, expanding our understanding of human history within and outside of Africa. This review will summarize some of the recent findings regarding African demographic history, including the African Diaspora, and will briefly explore their implications for disease susceptibility in populations of African descent.

Anal Cytology and Human Papillomavirus Genotyping in Women With a History of Lower Genital Tract Neoplasia Compared With Low-Risk Women.

Science.gov (United States)

Robison, Katina; Cronin, Beth; Bregar, Amy; Luis, Christine; DiSilvestro, Paul; Schechter, Steven; Pisharodi, Latha; Raker, Christina; Clark, Melissa

2015-12-01

To compare the prevalence of abnormal anal cytology and high-risk human papillomavirus (HPV) among women with a history of HPV-related genital neoplasia with women without a history of HPV-related genital neoplasia. A cross-sectional cohort study was performed from December 2012 to February 2014. Women were recruited from outpatient clinics at an academic medical center. Women with a history of high-grade cervical, vulvar, or vaginal cytology, dysplasia, or cancer were considered the high-risk group. Women with no history of high-grade anogenital dysplasia or cancer were considered the low-risk group. Human immunodeficiency virus-positive women were excluded. Anal cytology and HPV genotyping were performed. Women with abnormal anal cytology were referred for high-resolution anoscopy. There were 190 women in the high-risk group and 83 in the low-risk group. The high-risk group was slightly older: 57 years compared with 47 years (P=.045); 21.7% of low-risk women had abnormal anal cytology compared with 41.2% of high-risk women (P=.006). High-risk HPV was detected in the anal canal of 1.2% of the low-risk group compared with 20.8% of the high-risk group (PHuman immunodeficiency virus-negative women with a history of lower genital tract neoplasia are more likely to have positive anal cytology, anal high-risk HPV, and anal intraepithelial neoplasia. Anal cancer screening should be considered for these high-risk women. II.

The International Big History Association

Science.gov (United States)

Duffy, Michael; Duffy, D'Neil

2013-01-01

IBHA, the International Big History Association, was organized in 2010 and "promotes the unified, interdisciplinary study and teaching of history of the Cosmos, Earth, Life, and Humanity." This is the vision that Montessori embraced long before the discoveries of modern science fleshed out the story of the evolving universe. "Big…

Evolutionary history of Helicobacter pylori sequences reflect past human migrations in Southeast Asia.

Science.gov (United States)

Breurec, Sebastien; Guillard, Bertrand; Hem, Sopheak; Brisse, Sylvain; Dieye, Fatou Bintou; Huerre, Michel; Oung, Chakravuth; Raymond, Josette; Tan, Tek Sreng; Thiberge, Jean-Michel; Vong, Sirenda; Monchy, Didier; Linz, Bodo

2011-01-01

The human population history in Southeast Asia was shaped by numerous migrations and population expansions. Their reconstruction based on archaeological, linguistic or human genetic data is often hampered by the limited number of informative polymorphisms in classical human genetic markers, such as the hypervariable regions of the mitochondrial DNA. Here, we analyse housekeeping gene sequences of the human stomach bacterium Helicobacter pylori from various countries in Southeast Asia and we provide evidence that H. pylori accompanied at least three ancient human migrations into this area: i) a migration from India introducing hpEurope bacteria into Thailand, Cambodia and Malaysia; ii) a migration of the ancestors of Austro-Asiatic speaking people into Vietnam and Cambodia carrying hspEAsia bacteria; and iii) a migration of the ancestors of the Thai people from Southern China into Thailand carrying H. pylori of population hpAsia2. Moreover, the H. pylori sequences reflect iv) the migrations of Chinese to Thailand and Malaysia within the last 200 years spreading hspEasia strains, and v) migrations of Indians to Malaysia within the last 200 years distributing both hpAsia2 and hpEurope bacteria. The distribution of the bacterial populations seems to strongly influence the incidence of gastric cancer as countries with predominantly hspEAsia isolates exhibit a high incidence of gastric cancer while the incidence is low in countries with a high proportion of hpAsia2 or hpEurope strains. In the future, the host range expansion of hpEurope strains among Asian populations, combined with human motility, may have a significant impact on gastric cancer incidence in Asia.

Demographic Profile of Older Adults Using Wheeled Mobility Devices

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Amol M. Karmarkar

2011-01-01

Full Text Available The purpose of this study was to determine whether the use of wheeled mobility devices differed with respect to age, gender, residential setting, and health-related factors among older adults. A total of 723 adults ageing 60 and older are representing three cohorts, from nursing homes, the Center for Assistive Technology, and the wheelchair registry from the Human Engineering Research Laboratories. Wheeled mobility devices were classified into three main groups: manual wheelchairs, power wheelchairs, and scooters. Our results found factors including age, gender, diagnosis, and living settings to be associated with differences in use of manual versus powered mobility devices. Differences in use were also noted for subtypes of manual (depot, standard, and customized and powered (scooter, standard, and customized mobility devices, on demographic, living arrangements, and health-related factors. Consideration of demographic, health-related, and environmental factors during the prescription process may help clinicians identify the most appropriate mobility device for the user.

A Brief History of the 19th-century Historical and Comparative Linguistics

Institute of Scientific and Technical Information of China (English)

郭丽娟

2016-01-01

In a broad sense Linguistics boasts a history as long as the history of writing. Knowledge of linguistics involves its history. And a history of linguistics is related to the origin of human language. Language is one of the most wonderful phenomena in human ’s social life. This paper introduce a brief history of historical and comparative linguistics in 19th–century.

Humans and viticulture in Sardinia: The history and social relations as signs of identity of the wine-growing area

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Benedetto Graziella

2014-01-01

Full Text Available The premise of this paper is that viticulture is an expression of history and social relations. In this sense, we embrace a post-modern vision of development that characterized both economic and cultural geography and agricultural economics. Such an approach does consider culture as an element of mediation between humans and the nature, placing it at the heart of the wine-growing territory. So history and social relations have influenced the today spatial densification by types of grape and the persistence, the reduction and/or disappearance of vines’ cultivations due to the different level of integration between humans and wine territories in the Italian region of Sardinia. In this region, there are selected areas where winegrowers have been forced to grub vineyards up, depleting the regional viticultural heritage, others–within which the fabric of the system of social relationships were denser–and where we saw a real rush to purchase of replanting rights for the expansion of the production surface for the increasing of production. The aim of this paper is to highlight the role of history and social relations in the determination of the structure of the regional viticulture through the identification and analysis of diverse case studies.

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

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Suhail N Al-Shammri

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

Inclusive fitness and differential productivity across the life course determine intergenerational transfers in a small-scale human society.

Science.gov (United States)

Hooper, Paul L; Gurven, Michael; Winking, Jeffrey; Kaplan, Hillard S

2015-03-22

Transfers of resources between generations are an essential element in current models of human life-history evolution accounting for prolonged development, extended lifespan and menopause. Integrating these models with Hamilton's theory of inclusive fitness, we predict that the interaction of biological kinship with the age-schedule of resource production should be a key driver of intergenerational transfers. In the empirical case of Tsimane' forager-horticulturalists in Bolivian Amazonia, we provide a detailed characterization of net transfers of food according to age, sex, kinship and the net need of donors and recipients. We show that parents, grandparents and siblings provide significant net downward transfers of food across generations. We demonstrate that the extent of provisioning responds facultatively to variation in the productivity and demographic composition of families, as predicted by the theory. We hypothesize that the motivation to provide these critical transfers is a fundamental force that binds together human nuclear and extended families. The ubiquity of three-generational families in human societies may thus be a direct reflection of fundamental evolutionary constraints on an organism's life-history and social organization.

Urine Pretreatment History and Perspective in NASA Human Spaceflight

Science.gov (United States)

Anderson, Molly; Adam, Niklas; Chambers, Antja; Broyan, James

2015-01-01

Urine pretreatment is a technology that may seem to have small mass impacts in future spaceflight missions, but can have significant impacts on reliability, life, and performance of the rest of the wastewater management and recovery systems. NASA has experience with several different urine pretreatment systems, including those flow on the space shuttle, evaluated for NASA waste collection systems or used in Russian commodes on ISS, or developed by NASA or industry as alternatives. Each has had unique requirements for shelf life, operational life, and the life or conditions of the stored, treated urine. Each was evaluated under different test conditions depending on mission, and depending on testing experience developed over NASA's history. Those that were flown led to further lessons learned about hardware compatibility and control. As NASA looks forward to human spaceflight missions beyond low Earth orbit, these techniques need to be evaluated in new light. Based on published design reference missions, candidate requirements can be derived for future systems. Initial comparisons between these requirements and previous performance or test results can be performed. In many cases these comparisons reveal data gaps. Successful previous performance is not enough to address current needs.

Genetic tools link long-term demographic and life-history traits of anemonefish to their anemone hosts

KAUST Repository

Salles, Océ ane C.; Saenz-Agudelo, Pablo; Almany, Glenn R.; Berumen, Michael L.; Thorrold, Simon R.; Jones, Geoffrey P.; Planes, Serge

2016-01-01

The life-history traits and population dynamics of species are increasingly being attributed to the characteristics of their preferred habitats. While coral reef fish are often strongly associated with particular habitats, long-term studies

Prevention interventions for human immunodeficiency virus in drug-using women with a history of partner violence

Directory of Open Access Journals (Sweden)

Stockman JK

2012-02-01

Full Text Available Jamila K Stockman1, Natasha Ludwig-Barron1, Monica A Hoffman2, Monica D Ulibarri3, Typhanye V Penniman Dyer41Division of Global Public Health, Department of Medicine; 2Department of Communication and Science Studies; 3Department of Psychiatry, University of California, San Diego, La Jolla, CA; 4Department of Epidemiology and Biostatistics, University of Maryland School of Public Health, College Park, MD, USAAbstract: The intersecting epidemics of human immunodeficiency virus (HIV and partner violence disproportionately affect women who use drugs. Despite accumulating evidence throughout the world linking these epidemics, HIV prevention efforts focused on these synergistic issues as well as underlying determinants that contribute to the HIV risk environment (eg, housing instability, incarceration, policing practices, survival sex are lacking. This article highlights selected behavior change theories and biomedical approaches that have been used or could be applied in HIV prevention interventions for drug-using women with histories of partner violence and in existing HIV prevention interventions for drug-using women that have been gender-focused while integrating histories of partner violence and/or relationship power dynamics. To date, there is a paucity of HIV prevention interventions designed for drug-using women (both in and outside of drug treatment programs with histories of partner violence. Of the few that exist, they have been theory-driven, culture-specific, and address certain aspects of gender-based inequalities (eg, gender-specific norms, relationship power and control, partner violence through assessment of personal risk and safety planning. However, no single intervention has addressed all of these issues. Moreover, HIV prevention interventions for drug-using women with histories of partner violence are not widespread and do not address multiple components of the risk environment. Efficacious interventions should target individuals

Genetics of the pig tapeworm in madagascar reveal a history of human dispersal and colonization.

Science.gov (United States)

Yanagida, Tetsuya; Carod, Jean-François; Sako, Yasuhito; Nakao, Minoru; Hoberg, Eric P; Ito, Akira

2014-01-01

An intricate history of human dispersal and geographic colonization has strongly affected the distribution of human pathogens. The pig tapeworm Taenia solium occurs throughout the world as the causative agent of cysticercosis, one of the most serious neglected tropical diseases. Discrete genetic lineages of T. solium in Asia and Africa/Latin America are geographically disjunct; only in Madagascar are they sympatric. Linguistic, archaeological and genetic evidence has indicated that the people in Madagascar have mixed ancestry from Island Southeast Asia and East Africa. Hence, anthropogenic introduction of the tapeworm from Southeast Asia and Africa had been postulated. This study shows that the major mitochondrial haplotype of T. solium in Madagascar is closely related to those from the Indian Subcontinent. Parasitological evidence presented here, and human genetics previously reported, support the hypothesis of an Indian influence on Malagasy culture coinciding with periods of early human migration onto the island. We also found evidence of nuclear-mitochondrial discordance in single tapeworms, indicating unexpected cross-fertilization between the two lineages of T. solium. Analyses of genetic and geographic populations of T. solium in Madagascar will shed light on apparently rapid evolution of this organism driven by recent (<2,000 yr) human migrations, following tens of thousands of years of geographic isolation.

Humans to Mars: The Greatest Adventure in Human History

Science.gov (United States)

Levine, Joel S.; Schild,Rudy

2011-01-01

The reasons for a human mission to Mars are many and include (1) World technological leadership, (2) Enhanced national security, (3) Enhanced economic vitality, (4) The human urge to explore new and distant frontiers, (5) Scientific discovery (how did Mars evolve from an early Earth-like, hospitable planet to its present inhospitable state? Is there life on Mars?) (6) Inspiring the American public and the next generation of scientists and engineers (following the launch of Sputnik I by the USSR on October 4, 1957, the U. S. and the rest of the world witnessed a significant increase in the number of students going into science and engineering), (7) Develop new technologies for potential non-space spin-off applications, and, (8) Enhanced national prestige, etc. Other reasons for colonizing the Red Planet are more catastrophic in nature, including Mars as a safe haven for the survival of the human species in the event of an impact with a large asteroid (remember the demise of the dinosaurs 65-million years as a result of an asteroid impact!). Some have also suggested that the colonization of Mars may be a solution to the global exponential population explosion on our planet! A human mission to and the colonization of the Red Planet requires multi-disciplined expertise in many areas including engineering, technology, science, human health and medicine and the human psychological and behavior. To capture the relevant areas of needed expertise, we have invited a group of more than 70 U. S. and foreign experts in these areas, including astronauts, scientists, engineers, technologists, medical doctors, psychologists and economists to share their views and thoughts on a human mission to Mars.

High adult mortality among Hiwi hunter-gatherers: implications for human evolution.

Science.gov (United States)

Hill, Kim; Hurtado, A M; Walker, R S

2007-04-01

Extant apes experience early sexual maturity and short life spans relative to modern humans. Both of these traits and others are linked by life-history theory to mortality rates experienced at different ages by our hominin ancestors. However, currently there is a great deal of debate concerning hominin mortality profiles at different periods of evolutionary history. Observed rates and causes of mortality in modern hunter-gatherers may provide information about Upper Paleolithic mortality that can be compared to indirect evidence from the fossil record, yet little is published about causes and rates of mortality in foraging societies around the world. To our knowledge, interview-based life tables for recent hunter-gatherers are published for only four societies (Ache, Agta, Hadza, and Ju/'hoansi). Here, we present mortality data for a fifth group, the Hiwi hunter-gatherers of Venezuela. The results show comparatively high death rates among the Hiwi and highlight differences in mortality rates among hunter-gatherer societies. The high levels of conspecific violence and adult mortality in the Hiwi may better represent Paleolithic human demographics than do the lower, disease-based death rates reported in the most frequently cited forager studies.

The Natural History of Oral Human Papillomavirus in Young Costa Rican Women.

Science.gov (United States)

Beachler, Daniel C; Lang Kuhs, Krystle A; Struijk, Linda; Schussler, John; Herrero, Rolando; Porras, Carolina; Hildesheim, Allan; Cortes, Bernal; Sampson, Joshua; Quint, Wim; Gonzalez, Paula; Kreimer, Aimée R

2017-07-01

Oral human papillomavirus (HPV) infection and related oropharyngeal cancer are uncommon in lower-income countries, particularly compared to HPV-associated cervical cancer. However, little is known about the natural history of oral HPV in less-developed settings and how it compares to the natural history of cervical HPV. Three hundred fifty women aged 22 to 33 years from the Costa Rica Vaccine Trial provided exfoliated cells from the cervical and oral regions at 2 visits 2 years apart. Samples from both visits were tested for 25 characterized α HPV types by the SPF10 PCR-DNA enzyme immunoassay-LiPA25 version 1 system. Risk factors for oral HPV persistence were calculated utilizing generalized estimating equations with a logistic link. Among the 82 women with characterized α oral HPV DNA detected at baseline, 14 persisted and were detected 2 years later (17.6%; 95% confidence interval [CI], 10.9-28.5%) and was similar to the persistence of α cervical HPV (40/223; 17.7%; 95% CI, 13.1-23.9%; P = 0.86). Acquisition of new α oral HPV type was low; incident infection (1.7%; 95% CI, 0.6-3.7%). Oral HPV DNA is uncommon in young women in Latin America, and often appears to clear within a few years at similar rates to cervical HPV.

Impact of demographic factors, early family relationships and depressive symptomatology in teenage pregnancy.

Science.gov (United States)

Quinlivan, Julie A; Tan, Louisa H; Steele, Angela; Black, Kirsten

2004-04-01

Teenage pregnancy has been well studied from a demographic risk perspective, but less data examining the early interpersonal family experiences of teenage mothers are available. We aimed to explore the relative impact of demographic, early interpersonal family relationships and depressive symptomatology as associations for teenage, as compared to non-teenage, childbearing. A prospective cross-sectional cohort study was undertaken. Institutional ethics committee approval and informed consent were obtained. Data from consecutive teenage (teenage) and non-teenage (control) subgroups of antenatal women were compared. Subjects were interviewed and completed the following questionnaires: demographic, drug use and lifestyle; early life experiences; Hospital Anxiety and Depression Scale (HADS); and General Health Questionnaire-28. In multivariate analysis, the following factors had a significant independent association with younger age of motherhood in order of magnitude: a history of parental separation/divorce in early childhood; exposure to family violence in early childhood; illicit drug use (ever or in pregnancy); idealization of the pregnancy; low family income; a positive HADS-A or HADS-D subscale score; and a low level of education. Interventions to reduce the rate of teenage births need to be multifocal and should include strategies to address early childhood exposure to parental separation and violence, reduce idealization of pregnancy, diagnose psychological symptomatology and offer alternative career choices to children defaulting in the education system.

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

Science.gov (United States)

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

2007-01-01

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

Evolutionary forces shaping genomic islands of population differentiation in humans

Directory of Open Access Journals (Sweden)

Hofer Tamara

2012-03-01

strongly differentiated between Africans and non-Africans, a result consistent with known human demographic history.

Relationship Between Tetanus Antitoxin Titration Level and Vaccination History

OpenAIRE

Işıkgöz Taşbakan, Meltem; Durusoy, Raika; Tosun, Selma

2017-01-01

Objectives: We aimed to determine tetanus antitoxin levels and to evaluate their relationship with history of vaccination among patients applying to the outpatient clinics of a University hospital. Methods: A questionnaire including socio-demographic characteristics and tetanus vaccination status was applied and blood samples taken from 218 subjects between 1 and 30 June 2015. Participants were classified into five groups according to their vaccination timing. Results: The mean age of...

Increased mortality exposure within the family rather than individual mortality experiences triggers faster life-history strategies in historic human populations

NARCIS (Netherlands)

Störmer, Charlotte; Lummaa, Virpi

2014-01-01

impact of family versus individual-level effects of mortality exposure on two central life-history parameters, ages at first marriage and first birth, in three historical human populations (Germany, Finland, Canada). Mortality experience is measured as the confrontation with sibling deaths within

Public Pension Reform, Demographics, and Inequality

OpenAIRE

von Weizsäcker, Robert K

1994-01-01

Starting from a simple, descriptive model of individual income, an explicit link between the age composition of a population and the personal distribution of incomes is established. Demographic effects on income inequality are derived. Next, a pay-as-you-go financed state pension system is introduced. The resulting government budget constraint entails interrelations between fiscal and demographic variables, causing an additional, indirect demographic impact on the distribution. This is shown ...

Gender inequalities from the demographic perspective

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Devedžić Mirjana

2006-01-01

Full Text Available The paper analyzes the meaning of the phrase "the woman’s status in the society" that is recognized in demography as an important cultural factor of demographic development and transitional changes. The analysis indicates qualitative shifts in the woman’s status and simultaneously reveals its importance at present, not only in traditional, but also in modern and developed societies. On the other hand, it explains the importance of sex as a biodemographic determinant, and introduces the concept of gender that sheds another light on the concepts of sex and woman’s status in the society and integrates them. Gender regimes that subsume the inferiority of women in public and private social structures are examined from demographic perspective, albeit only in those phenomenological aspects that can be supported by demographic research, theories, and analyses. To this end, the paper analyzes the effects of strengthening gender equalities on the fertility and mortality transitions, the gender’s impact on the population distribution by sex in South Asian countries, and highlights the key role of gender in interpreting certain social and economic structures. It also stresses the establishing of gender equality as an important element of population policies. The global dimension of the patriarchal society is illustrated through a series of examples of demographic phenomena from various societies. Gender regimes underlie all of these phenomena. The paper puts foreword certain theoretical hypotheses about gender inequalities, and finds their connections with demographic behaviors and demographic indicators. Finally, it summarizes the role of demography in gender (inequality research and the demographic perspective of the way and the speed the demographic equality is being established. Demography is seen as an irreplaceable discipline in examining gender inequalities, especially at the global level. With the advance of qualitative methods in demography

Beyond demographics is destiny: understanding economic mitigation strategies for demographic change in China

OpenAIRE

Judy, John B.

2015-01-01

Approved for public release; distribution is unlimited The favorable demographics that have contributed to China’s rapid economic growth are changing. China’s working-age population is currently peaking and within two decades its overall population will begin to shrink. In addition to a shrinking working-age population, China will see an increase in the elderly population and a rising dependency ratio. This demographic change may have an economically significant impact. If China’s enormous...

Evolutionary demography and the population history of the European early Neolithic.

Science.gov (United States)

Shennan, Stephen

2009-04-01

In this paper I propose that evolutionary demography and associated theory from human behavioral ecology provide a strong basis for explaining the available evidence for the patterns observed in the first agricultural settlement of Europe in the 7th-5th millennium cal. BC, linking together a variety of what have previously been disconnected observations and casting doubt on some long-standing existing models. An outline of relevant aspects of life history theory, which provides the foundation for understanding demography, is followed by a review of large-scale demographic patterns in the early Neolithic, which point to rapid population increase and a process of demic diffusion. More localized socioeconomic and demographic patterns suggesting rapid expansion to local carrying capacities and an associated growth of inequality in the earliest farming communities of central Europe (the Linear Pottery Culture, or LBK) are then outlined and shown to correspond to predictions of spatial population ecology and reproductive skew theory. Existing models of why it took so long for farming to spread to northern and northwest Europe, which explain the spread in terms of the gradual disruption of hunter-gatherer ways of life, are then questioned in light of evidence for population collapse at the end of the LBK. Finally, some broader implications of the study are presented, including the suggestion that the pattern of an initial agricultural boom followed by a bust may be relevant in other parts of the world.

Demographic Trends: Impact on Schools

Science.gov (United States)

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

2010-01-01

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

The use of mobile phones for demographic surveillance of mobile pastoralists and their animals in Chad: proof of principle.

Science.gov (United States)

Jean-Richard, Vreni; Crump, Lisa; Moto Daugla, Doumagoum; Hattendorf, Jan; Schelling, Esther; Zinsstag, Jakob

2014-01-01

Demographic information is foundational for the planning and management of social programmes, in particular health services. The existing INDEPTH network surveillance sites are limited to coverage of sedentary populations. Including mobile populations in this approach would be expensive, time consuming and possibly low in accuracy. Very little is known about the demography of mobile pastoralists and their animals, so innovative approaches are urgently needed. To test and evaluate a mobile demographic surveillance system for mobile pastoralist households, including livestock herds, using mobile phones. Mobile pastoralist camps were monitored (10 for 12 months and 10 for 18 months) using biweekly mobile phone calls with camp leaders and their wives to conduct interviews about the households and livestock. The collected information was validated through personal visits, GPS data and a livestock demographic model. The study showed the feasibility of mobile phone surveillance for mobile pastoralist camps, providing usable, valid information on human and livestock population structures, pregnancy outcomes and herd dynamics, as well as migration patterns. The approach was low-cost and applicable with the existing local resources. Demographic surveillance in mobile populations is feasible using mobile phones. Expansion of the small-scale system into a full mobile demographic surveillance system is warranted and would likely lead to improved planning and provision of human and animal health care.

Influence of life history strategies on sensitivity, population growth and response to climate for sympatric alpine birds

Directory of Open Access Journals (Sweden)

Wilson Scott

2012-06-01

Full Text Available Abstract Background The life history strategy of a species can influence how populations of that species respond to environmental variation. In this study, we used a matrix modeling approach to examine how life history differences among sympatric rock and white-tailed ptarmigan affect the influence of demographic rates on population growth (λ and the potential response to a changing climate. Rock ptarmigan have a slower life history strategy than white-tailed ptarmigan in the study region with lower annual reproductive effort but higher adult survival. Results Based on data from a 5-year field study, deterministic estimates of λ indicated that populations were stable for rock ptarmigan (λ = 1.01, but declining for white-tailed ptarmigan (λ = 0.96. The demographic rates with the highest elasticity for rock ptarmigan were the survival of after-second year females, followed by juvenile survival and success of the first nest. For white-tailed ptarmigan, juvenile survival had the highest elasticity followed by success of the first nest and survival of second-year females. Incorporating stochasticity into the demographic rates led to a 2 and 4% drop in λ for rock and white-tailed ptarmigan respectively. Using data from the first three years we also found that population growth rates of both species were depressed following an increased frequency of severe years, but less so for rock ptarmigan which showed greater resilience under these conditions. Conclusions Our results provide evidence that populations of closely related species can vary in their response to environmental change as a consequence of life history differences. Rock ptarmigan, with a slower life history, are more responsive to demographic rates that influence survival and older life stages but this response is tempered by the extent of variability in each of the rates. Thus, predictions need to consider both aspects in modeling population response to a varying climate

The IL--6 dependent effect of oral warfarin in heart valve replacement patients by measuring interacting clinical and demographic variables

International Nuclear Information System (INIS)

Shafiq, H.; Rashid, A.; Majeed, A.; Razah, S.; Asghar, I.

2016-01-01

Objective: To examine an inflammatory effect of warfarin and comparing with IL-6 levels along with different demographic and clinical variables. Study Design: Quasi experimental study. Place and Duration of Study: Center of Research in Experimental and Applied Medicine (CREAM), Army Medical College/National University of Sciences and Technology, Islamabad from Oct 2013 to Oct 2015. Material and Methods: The study design was Quasi Experimental study. Samples were collected by Non probability convenience sampling. Total 76 patients were included according to warfarin dose response in warfarin therapy patients, i.e. 32(42 percent) were taking 10mg/day of warfarin dose. Patient's demographic and clinical variables were noted i.e. age, gender, BMI, duration of therapy, INR history, hepatic, gastrointestinal and diabetic complications. Human IL-6 ELISA assay was performed. Results: The statistically significant difference was found between age groups (in years) and different levels of warfarin dose (p=0.046) along with IL-6 production. There is a negative correlation between warfarin dose and age group i.e. as age increases, the dose of warfarin decreases. Among the inter and intra-patient variability age and serum IL-6 levels were found to be statistically significant with warfarin dose response. BMI and warfarin dose were found to be weak positively correlated. Conclusion: A marked immunomodulatory response of warfarin was noted by measuring IL-6 levels. IL-6 levels retained a significant association with warfarin dose. (author)

Strong population bottleneck and repeated demographic expansions of Populus adenopoda (Salicaceae) in subtropical China.

Science.gov (United States)

Fan, Liqiang; Zheng, Honglei; Milne, Richard I; Zhang, Lei; Mao, Kangshan

2018-03-14

Glacial refugia and inter-/postglacial recolonization routes during the Quaternary of tree species in Europe and North America are well understood, but far less is known about those of tree species in subtropical eastern Asia. Thus, we have examined the phylogeographic history of Populus adenopoda (Salicaceae), one of the few poplars that naturally occur in this subtropical area. Genetic variations across the range of the species in subtropical China were surveyed using ten nuclear microsatellite loci and four chloroplast fragments (matK, trnG-psbK, psbK-psbI and ndhC-trnV). Coalescent-based analyses were used to test demographic and migration hypotheses. In addition, species distribution models (SDMs) were constructed to infer past, present and future potential distributions of the species. Thirteen chloroplast haplotypes were detected, and haplotype-rich populations were found in central and southern parts of the species' range. STRUCTURE analyses of nuclear microsatellite loci suggest obvious lineage admixture, especially in peripheral and northern populations. DIYABC analysis suggests that the species might have experienced two independent rounds of demographic expansions and a strong bottleneck in the late Quaternary. SDMs indicate that the species' range contracted during the Last Glacial Maximum (LGM), and contracted northward but expanded eastward during the Last Interglacial (LIG). Chloroplast data and SDMs suggest that P. adenopoda might have survived in multiple glacial refugia in central and southern parts of its range during the LGM. Populations of the Yunnan-Guizhou Plateau in the southern part have high chloroplast DNA diversity, but may have contributed little to the postglacial recolonization of northern and eastern parts. The three major demographic events inferred by DIYABC coincide with the initiation of the LIG, start of the LGM and end of the LGM, respectively. The species may have experienced multiple rounds of range contraction during

Atmospheric nuclear weapon test history as characterized by the deposition of 14C in human teeth

International Nuclear Information System (INIS)

Nishizawa, K.; Togari, A.; Matsumoto, S.; Nagatsu, T.

1990-01-01

The 14 C concentration in the collagen of human teeth was retrospectively investigated to determine whether its incorporation was related to atmospheric testing of nuclear weapons. Teeth were extracted for dental therapy from July 1987 to February 1988 from patients who were residents in Japan. Tooth collagen was extracted with HCl and converted to amorphous C by heating in a vacuum line. Specimens for 14 C analysis were prepared by mixing the amorphous C with silver powder. The 14 C concentration was measured by mass spectrometer. The 14 C concentration in tooth collagen rapidly increased in 1961 after the bomb tests, peaked around 1967-1968, and then gradually decreased. The collagen of human teeth maintains the 14 C concentration at the age of root completion for life. The results of this study indicate that the history of environmental contamination from atmospheric nuclear weapon's tests has been characterized by deposition of 14 C in the tooth collagen 14 C of human beings

Demographic Analysis from Biometric Data: Achievements, Challenges, and New Frontiers.

Science.gov (United States)

Sun, Yunlian; Zhang, Man; Sun, Zhenan; Tan, Tieniu

2018-02-01

Biometrics is the technique of automatically recognizing individuals based on their biological or behavioral characteristics. Various biometric traits have been introduced and widely investigated, including fingerprint, iris, face, voice, palmprint, gait and so forth. Apart from identity, biometric data may convey various other personal information, covering affect, age, gender, race, accent, handedness, height, weight, etc. Among these, analysis of demographics (age, gender, and race) has received tremendous attention owing to its wide real-world applications, with significant efforts devoted and great progress achieved. This survey first presents biometric demographic analysis from the standpoint of human perception, then provides a comprehensive overview of state-of-the-art advances in automated estimation from both academia and industry. Despite these advances, a number of challenging issues continue to inhibit its full potential. We second discuss these open problems, and finally provide an outlook into the future of this very active field of research by sharing some promising opportunities.

[The demographic potential of Russia].

Science.gov (United States)

Vishnevskii, A

1998-05-01

This is a general review of current demographic trends in Russia. The author analyzes the decline in population size that is taking place at the end of the twentieth century, and traces its origins as far back as the disturbances associated with World War I, the Communist revolution, and the civil war that followed it. Political repression during the Stalinist period and the tribulations experienced during World War II also contributed to the current demographic crisis. The author discusses the changes in migration patterns and the declining fertility and increasing mortality rates. The decline in life expectancy is also addressed. Some comparisons are made with the demographic situation in other European countries.

Molecular phylogeography and evolutionary history of Poropuntius huangchuchieni (Cyprinidae in Southwest China.

Directory of Open Access Journals (Sweden)

Xiaoyun Wu

Full Text Available The evolution of the Yunnan Plateau's drainages network during the Pleistocene was dominated by the intense uplifts of the Qinghai-Tibetan Plateau. In the present study, we investigated the association between the evolutionary histories of three main drainage systems and the geographic patterns of genetic differentiation of Poropuntius huangchuchieni.We sequenced the complete sequences of mitochondrial control region for 304 specimens and the sequences of Cytochrome b gene for 15 specimens of the species P. huangchuchieni and 5 specimens of Poropuntius opisthoptera. Phylogenetic analysis identified five major lineages, of which lineages MK-A and MK-B constrained to the Mekong River System, lineages RL and LX to the Red River System, and lineage SW to the Salween River System. The genetic distance and network analysis detected significant divergences among these lineages. Mismatch distribution analysis implied that the population of P. huangchuchieni underwent demographic stability and the lineage MK-B, sublineages MK-A1 and LX-1 underwent a recent population expansion. The divergence of the 5 major lineages was dated back to 0.73-1.57 MYA.Our results suggest that P. opisthoptera was a paraphyletic group of P. huangchuchieni. The phylogenetic pattern of P. huangchuchieni was mostly associated with the drainage's structures and the geomorphological history of the Southwest Yunnan Plateau. Also the differentiation of the major lineages among the three drainages systems coincides with the Kunlun-Yellow River Movement (1.10-0.60 MYA. The genetic differentiation within river basins and recent demographical expansions that occurred in some lineages and sublineages are consistent with the palaeoclimatic oscillations during the Pleistocene. Additionally, our results also suggest that the populations of P. huangchuchieni had keep long term large effective population sizes and demographic stability in the recent evolutionary history, which may be

The history of African trypanosomiasis

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Steverding Dietmar

2008-02-01

Full Text Available Abstract The prehistory of African trypanosomiasis indicates that the disease may have been an important selective factor in the evolution of hominids. Ancient history and medieval history reveal that African trypanosomiasis affected the lives of people living in sub-Saharan African at all times. Modern history of African trypanosomiasis revolves around the identification of the causative agents and the mode of transmission of the infection, and the development of drugs for treatment and methods for control of the disease. From the recent history of sleeping sickness we can learn that the disease can be controlled but probably not be eradicated. Current history of human African trypanosomiasis has shown that the production of anti-sleeping sickness drugs is not always guaranteed, and therefore, new, better and cheaper drugs are urgently required.

Lung Cancer Risk and Demographic Characteristics of Current 20-29 Pack-year Smokers: Implications for Screening.

Science.gov (United States)

Pinsky, Paul F; Kramer, Barnett S

2015-11-01

Based on current recommendations, 30+ pack-years of smoking are required for eligibility for low-dose CT (LDCT) lung cancer screening; former smokers must have quit within 15 years. We investigated whether current smokers with 20 to 29 pack-years have similar lung cancer risks as eligible former smokers and also whether they have a different demographic profile. The Prostate, Lung, Colorectal, and Ovarian Cancer Screening Trial (PLCO) was a randomly assigned screening trial of subjects age 55 to 74 years with chest radiographs (CXR) used for lung cancer. Subjects completed a baseline questionnaire containing smoking history questions. Cox proportional hazards models, adjusted for age and sex, were utilized to estimate hazard ratios (HRs) for various smoking history groups. Next, we utilized the National Health Interview Survey (NHIS), which inquired about smoking history and race/ethnicity, to analyze the demographic profiles of various high-risk smoking history categories. All statistical tests were two-sided. The PLCO cohort included 18 114 former and 12 243 current LDCT-eligible smokers, plus 2283 20- to 29-pack-year current smokers. The hazard ratio for 20- to 29-pack-year current smokers compared with eligible (30+ pack-year) former smokers was 1.07 (95% confidence interval [CI] = 0.75 to 1.5). Based on the NHIS, 10 million persons in the United States are currently LDCT eligible; an additional 1.6 million (16%, 95% CI = 13.6% to 19.0%) are 20- to 29-pack-year current smokers. The percentage increase in eligibles if 20- to 29-pack-year current smokers were included was substantially greater for women than men (22.2%, 95% CI = 17.9% to 26.7%; vs 12.2%, 95% CI = 9.3% to 15.3%, P non-Hispanic whites (30.0%, 95% CI = 24.2% to 36.0%; vs 14.1%, 95% CI = 11.1% to 17.0%, P smokers should be assessed. Published by Oxford University Press 2015. This work is written by (a) US Government employee(s) and is in the public domain in the US.

Rewrite history, make history. Woman as subject in Christine de Pizan and Margaret Cavendish

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Paola Rudan

2016-07-01

Full Text Available In The City of Ladies and Bell in Campo, Christine de Pizan and Margaret Cavendish imagine women’s participation to war as a metaphor of the sexual conflict that they must fight in order to conquer their visibility in history. While Pizan rewrites history from women’s stand point and acknowledges the universal value of sexual difference for the plan of salvation, Cavendish moves within a modern frame and thinks history as the result of human action. In both cases, the tale of women’s participation to war allows criticizing the moral and normative implications of «nature».

Estimating demographic contributions to effective population size in an age-structured wild population experiencing environmental and demographic stochasticity.

Science.gov (United States)

Trask, Amanda E; Bignal, Eric M; McCracken, Davy I; Piertney, Stuart B; Reid, Jane M

2017-09-01

A population's effective size (N e ) is a key parameter that shapes rates of inbreeding and loss of genetic diversity, thereby influencing evolutionary processes and population viability. However, estimating N e , and identifying key demographic mechanisms that underlie the N e to census population size (N) ratio, remains challenging, especially for small populations with overlapping generations and substantial environmental and demographic stochasticity and hence dynamic age-structure. A sophisticated demographic method of estimating N e /N, which uses Fisher's reproductive value to account for dynamic age-structure, has been formulated. However, this method requires detailed individual- and population-level data on sex- and age-specific reproduction and survival, and has rarely been implemented. Here, we use the reproductive value method and detailed demographic data to estimate N e /N for a small and apparently isolated red-billed chough (Pyrrhocorax pyrrhocorax) population of high conservation concern. We additionally calculated two single-sample molecular genetic estimates of N e to corroborate the demographic estimate and examine evidence for unobserved immigration and gene flow. The demographic estimate of N e /N was 0.21, reflecting a high total demographic variance (σ2dg) of 0.71. Females and males made similar overall contributions to σ2dg. However, contributions varied among sex-age classes, with greater contributions from 3 year-old females than males, but greater contributions from ≥5 year-old males than females. The demographic estimate of N e was ~30, suggesting that rates of increase of inbreeding and loss of genetic variation per generation will be relatively high. Molecular genetic estimates of N e computed from linkage disequilibrium and approximate Bayesian computation were approximately 50 and 30, respectively, providing no evidence of substantial unobserved immigration which could bias demographic estimates of N e . Our analyses identify

A Community Patient Demographic System

OpenAIRE

Gabler, James M.; Simborg, Donald W.

1985-01-01

A Community Patient Demographic System is described. Its purpose is to link patient identification, demographic and insurance information among multiple organizations in a community or among multiple registration systems within the same organization. This function requires that there be a competent patient identification methodology and clear definition of local responsibilities for number assignment and database editing.

75 FR 435 - Notice of Inventory Completion: Field Museum of Natural History, Chicago, IL

Science.gov (United States)

2010-01-05

... Natural History, Chicago, IL. The human remains were removed from the Channel Islands in Santa Barbara and.... A detailed assessment of the human remains was made by Field Museum of Natural History professional... 407). The human remains were accessioned into the Field Museum of Natural History the same year. No...

75 FR 45659 - Notice of Inventory Completion: Field Museum of Natural History, Chicago, IL

Science.gov (United States)

2010-08-03

... possession of the Field Museum of Natural History, Chicago, IL. The human remains and associated funerary... assessment of the human remains was made by the Field Museum of Natural History professional staff in... History have determined that, pursuant to 25 U.S.C. 3001(9), the human remains described above represent...

Association between shift work history and performance on the trail making test in middle-aged and elderly humans: the EpiHealth study.

Science.gov (United States)

Titova, Olga E; Lindberg, Eva; Elmståhl, Sölve; Lind, Lars; Schiöth, Helgi B; Benedict, Christian

2016-09-01

Shift work has been proposed to promote cognitive disturbances in humans; however, conflicting evidence is also present. By using data from 7143 middle-aged and elderly humans (45-75 years) who participated in the Swedish EpiHealth cohort study, the present analysis sought to investigate whether self-reported shift work history would be associated with performance on the trail making test (TMT). The TMT has been proposed to be a useful neuropsychological tool to evaluate humans' executive cognitive function, which is known to decrease with age. After adjustment for potential confounders (e.g., age, education, and sleep duration), it was observed that current and recent former shift workers (worked shifts during the past 5 years) performed worse on the TMT than nonshift workers. In contrast, performance on the TMT did not differ between past shift workers (off from shift work for more than 5 years) and nonshift workers. Collectively, our results indicate that shift work history is linked to poorer performance on the TMT in a cohort of middle-aged and elderly humans. Copyright © 2016 The Author(s). Published by Elsevier Inc. All rights reserved.

Prevention interventions for human immunodeficiency virus in drug-using women with a history of partner violence.

Science.gov (United States)

Stockman, Jamila K; Ludwig-Barron, Natasha; Hoffman, Monica A; Ulibarri, Monica D; Dyer, Typhanye V Penniman

2012-01-01

The intersecting epidemics of human immunodeficiency virus (HIV) and partner violence disproportionately affect women who use drugs. Despite accumulating evidence throughout the world linking these epidemics, HIV prevention efforts focused on these synergistic issues as well as underlying determinants that contribute to the HIV risk environment (eg, housing instability, incarceration, policing practices, survival sex) are lacking. This article highlights selected behavior change theories and biomedical approaches that have been used or could be applied in HIV prevention interventions for drug-using women with histories of partner violence and in existing HIV prevention interventions for drug-using women that have been gender-focused while integrating histories of partner violence and/or relationship power dynamics. To date, there is a paucity of HIV prevention interventions designed for drug-using women (both in and outside of drug treatment programs) with histories of partner violence. Of the few that exist, they have been theory-driven, culture-specific, and address certain aspects of gender-based inequalities (eg, gender-specific norms, relationship power and control, partner violence through assessment of personal risk and safety planning). However, no single intervention has addressed all of these issues. Moreover, HIV prevention interventions for drug-using women with histories of partner violence are not widespread and do not address multiple components of the risk environment. Efficacious interventions should target individuals, men, couples, and social networks. There is also a critical need for the development of culturally tailored combination HIV prevention interventions that not only incorporate evidence-based behavioral and biomedical approaches (eg, microbicides, pre-exposure prophylaxis, female-initiated barrier methods) but also take into account the risk environment at the physical, social, economic and political levels. Ultimately, this approach

"ALS reversals": demographics, disease characteristics, treatments, and co-morbidities.

Science.gov (United States)

Harrison, Daniel; Mehta, Paul; van Es, Michael A; Stommel, Elijah; Drory, Vivian E; Nefussy, Beatrice; van den Berg, Leonard H; Crayle, Jesse; Bedlack, Richard

2018-04-02

To identify differences in demographics, disease characteristics, treatments, and co-morbidities between patients with "amyotrophic lateral sclerosis (ALS) reversals" and those with typically progressive ALS. Cases of possible ALS reversals were found in prior publications, in the Duke ALS clinic, through self-referral or referral from other Neurologists, and on the internet. Of 89 possible reversals identified, 36 cases were included because chart or literature review confirmed their diagnosis and a robust, sustained improvement in at least one objective measure. Controls were participants in the Pooled Resource Open-Access ALS Clinical Trials database and the National ALS Registry. Cases and controls were compared using descriptive statistics. ALS reversals were more likely to be male, have limb onset disease, and initially progress faster. The prevalences of myasthenia gravis (MG) and purely lower motor neuron disease in cases were higher than estimates of these prevalences in the general population. The odds of taking curcumin, luteolin, cannabidiol, azathioprine, copper, glutathione, vitamin D, and fish oil were greater for cases than controls. When compared to patients with typically progressive ALS, patients with reversals differed in their demographics, disease characteristics, and treatments. While some of these patients may have had a rare antibody-mediated ALS mimicker, such as atypical myasthenia gravis, details of their exams, EMGs and family histories argue that this was unlikely. Instead, our data suggest that ALS reversals warrant evaluation for mechanisms of disease resistance and that treatments associated with multiple ALS reversals deserve further study.

[History of viral hepatitis].

Science.gov (United States)

Fonseca, José Carlos Ferraz da

2010-01-01

The history of viral hepatitis goes back thousands of years and is a fascinating one. When humans were first infected by such agents, a natural repetitive cycle began, with the capacity to infect billions of humans, thus decimating the population and causing sequelae in thousands of lives. This article reviews the available scientific information on the history of viral hepatitis. All the information was obtained through extensive bibliographic review, including original and review articles and consultations on the internet. There are reports on outbreaks of jaundice epidemics in China 5,000 years ago and in Babylon more than 2,500 years ago. The catastrophic history of great jaundice epidemics and pandemics is well known and generally associated with major wars. In the American Civil War, 40,000 cases occurred among Union troops. In 1885, an outbreak of catarrhal jaundice affected 191 workers at the Bremen shipyard (Germany) after vaccination against smallpox. In 1942, 28,585 soldiers became infected with hepatitis after inoculation with the yellow fever vaccine. The number of cases of hepatitis during the Second World War was estimated to be 16 million. Only in the twentieth century were the main agents causing viral hepatitis identified. The hepatitis B virus was the first to be discovered. In this paper, through reviewing the history of major epidemics caused by hepatitis viruses and the history of discovery of these agents, singular peculiarities were revealed. Examples of this include the accidental or chance discovery of the hepatitis B and D viruses.

Demographic controls of future global fire risk

Science.gov (United States)

Knorr, W.; Arneth, A.; Jiang, L.

2016-08-01

Wildfires are an important component of terrestrial ecosystem ecology but also a major natural hazard to societies, and their frequency and spatial distribution must be better understood. At a given location, risk from wildfire is associated with the annual fraction of burned area, which is expected to increase in response to climate warming. Until recently, however, only a few global studies of future fire have considered the effects of other important global environmental change factors such as atmospheric CO2 levels and human activities, and how these influence fires in different regions. Here, we contrast the impact of climate change and increasing atmospheric CO2 content on burned area with that of demographic dynamics, using ensembles of climate simulations combined with historical and projected population changes under different socio-economic development pathways for 1901-2100. Historically, humans notably suppressed wildfires. For future scenarios, global burned area will continue to decline under a moderate emissions scenario, except for low population growth and fast urbanization, but start to increase again from around mid-century under high greenhouse gas emissions. Contrary to common perception, we find that human exposure to wildfires increases in the future mainly owing to projected population growth in areas with frequent wildfires, rather than by a general increase in burned area.

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

Science.gov (United States)

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

2013-05-01

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

Genetic diversity, outcrossing rate, and demographic history along a climatic gradient in the ruderal plant Ruellia nudiflora (Acanthaceae)

OpenAIRE

Vargas-Mendoza, Carlos F.; Ortegón-Campos, Ilka; Marrufo-Zapata, Denis; Herrera, Carlos M.; Parra-Tabla, Víctor

2015-01-01

© 2015 Universidad Nacional Autónoma de México, Instituto de Biología. All Rights Reserved. Ruellia nudiflora has shown a high potential to easily invade disturbed areas. Outcrossing rate and genetic structure and diversity in this species were examined along a climatic gradient in the Yucatán Peninsula (Mexico) in order to understand the effects of environmental heterogeneity - isolation by environment (IBE) - as well as correlation in herkogamy on genetic structure, diversity, and demograph...

Demographic Ranking of the Baltic Sea States

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Sluka N.

2014-06-01

Full Text Available The relevance of the study lies in the acute need to modernise the tools for a more accurate and comparable reflection of the demographic reality of spatial objects of different scales. This article aims to test the methods of “demographic rankings” developed by Yermakov and Shmakov. The method is based on the principles of indirect standardisation of the major demographic coefficients relative to the age structure.The article describes the first attempt to apply the method to the analysis of birth and mortality rates in 1995 and 2010 for 140 countries against the global average, and for the Baltic Sea states against the European average. The grouping of countries and the analysis of changes over the given period confirmed a number of demographic development trends and the persistence of wide territorial disparities in major indicators. The authors identify opposite trends in ranking based on the standardised birth (country consolidation at the level of averaged values and mortality (polarisation rates. The features of demographic process development in the Baltic regions states are described against the global and European background. The study confirmed the validity of the demographic ranking method, which can be instrumental in solving not only scientific but also practical tasks, including those in the field of demographic and social policy.

Cerebrospinal fluid GABA concentration: relationship with impulsivity and history of suicidal behavior, but not aggression, in human subjects.

Science.gov (United States)

Lee, Royce; Petty, Frederick; Coccaro, Emil F

2009-01-01

The objective of this study was to assess the relationship between cerebrospinal fluid concentrations of the neurotransmitter gamma-aminobutyric acid (GABA) and measures of impulsivity and related behaviors (aggression and suicidality) in healthy volunteer and personality disordered subjects. CSF GABA levels, and measures of impulsivity, aggression, and history of suicidal behavior were obtained by morning lumbar puncture in 57 healthy volunteer subjects and in subjects with personality disorder. CSF GABA levels were not found to correlate with measures of aggression but were found to correlate directly with measures of impulsivity; e.g., a composite measure of impulsivity in all subjects (r=0.35, df=46, P=0.015) and in personality disordered subjects examined separately (r=0.39, df=30, P=0.029). In the personality disorder group, CSF GABA levels were higher among subjects with a history of suicidal behavior compared with those without this history. These data suggest that central GABAergic function correlates directly with impulsiveness and history of suicidal behavior, but not aggressiveness, in personality disordered subjects. This may be consistent with observations that high doses of benzodiazepines can lead to "behavioral disinhibition" in human subjects. Further work assessing this and other aspects of the central GABA system in personality disordered subjects are warranted.

On genocide and the Holocaust in Swedish History teaching

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Niklas Ammert

2015-08-01

Full Text Available Teaching about the Holocaust and other genocides is emphasized in Swedish History teaching. In Sweden there is a public authority commisioned to work with issues related to tolerance, democracy and human rights. It is this context and under these conditions, that Swedish History teachers select a variety of topics for their students to learn, as part of the History curriculum. In addition to the Holocaust, they teach about crimes against humanity committed under communist regimes, the genocide of Tutsies in Rwanda, and mass murder and ethnic cleansing in former Yugoslavia. Teachers use a multiplicity of uses of history and teaching methods. They conduct a scientific use of history when focusing on the historical contexts and explaining the background, motives and consequences of genocide. Teachers also stress the students’ personal reflections and standpoints in a moral use of history. The teaching aims at developing understanding and empathy among students.

Using Twitter for Demographic and Social Science Research: Tools for Data Collection and Processing

Science.gov (United States)

McCormick, Tyler H.; Lee, Hedwig; Cesare, Nina; Shojaie, Ali; Spiro, Emma S.

2017-01-01

Despite recent and growing interest in using Twitter to examine human behavior and attitudes, there is still significant room for growth regarding the ability to leverage Twitter data for social science research. In particular, gleaning demographic information about Twitter users--a key component of much social science research--remains a…

Energy and water budgets of larks in a life history perspective : Parental effort varies with aridity

NARCIS (Netherlands)

Tieleman, BI; Williams, JB; Visser, GH

We compared physiological, demographic, and ecological variables of larks to gain insights into life history variation along an aridity gradient, incorporating phylogenetic relationships in analyses when appropriate. Quantifying field metabolic rate (FMR). and water influx rate (WIR) of parents

History of Bioterrorism: Botulism

Medline Plus

Full Text Available ... is Doing Blog: Public Health Matters Video: "The History of Bioterrorism" Recommend on Facebook Tweet Share Compartir ... 6348 Email CDC-INFO U.S. Department of Health & Human Services HHS/Open USA.gov TOP

Impact of Demographic, Socioeconomic and Psychological Factors on Glycemic Self-Management in Adults with Type 2 Diabetes Mellitus

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Alicia Alicia Gonzalez Zacarias

2016-09-01

Full Text Available Diabetes Mellitus (DM is reported as one of the most complex chronic diseases worldwide. In the United States, Type 2 Diabetes Mellitus (T2DM is the seventh leading cause of morbidity and mortality. Individuals with diabetes require lifelong personal care to reduce the possibility of developing long-term complications. A good knowledge of diabetes risk factors, including obesity, dyslipidemia, hypertension, family history of DM, and sedentary lifestyle, play an essential role in prevention and treatment. Also, socio-demographic, economic, psychological, and environmental factors are directly and indirectly associated with diabetes control and health outcomes. Our review intends to analyze the interaction between demographics, knowledge, environment, and other diabetes-related factors based on an extended literature search, and to provide insight for improving glycemic control and reducing the incidence of chronic complications.

Climate and Human History of Nature

DEFF Research Database (Denmark)

Frølund, Sune

2015-01-01

The paper investigates the ideas that have prevented environmental knowledge from developing into action and change. According to Clarence J. Glacken throughout European history design ideas about the relation between man and nature have prevented the many local observations of the negative...... expose some ecological ideas – that nature itself is a perpetual equilibrium and that man lived in harmony with nature until the emergence of modernity (industrialisation, capitalism, and technology) – as illusions. Such ‘new’ ecological ideas can be seen as disguised versions of the old design idea...

Multiregional demographic projections in practice: a metropolitan example.

Science.gov (United States)

Congdon, P

1992-01-01

"This paper examines options for local and regional projections which reflect both demographic interdependencies with jobs and housing at this area scale, and the inapplicability of traditional demographic projection methods to population or areal subdivisions. This context for local demographic projections requires constraints (for example, to job and housing forecasts or to higher area totals), the use of proxy or explanatory indicators to predict demographic rates or totals, and parameterization of demographic schedules, to facilitate comparison across numerous localities and to set future assumptions about demographic components. The traditional framework of self-contained projection by deterministic cohort survival is therefore widened to include regio-scientific and stochastic modelling concepts. The framework for empirical analysis is London [England] and its boroughs." (SUMMARY IN FRE AND GER) excerpt

Our grandmothers, excluded from history, preservers and ...

African Journals Online (AJOL)

Our grandmothers, excluded from history, preservers and transmitters of indegenous values: ecomaternalistic approach. ... Journal of Religion and Human Relations ... It further calls for the retrieval of the said hidden histories of women which would hopefully be a lesson for the contemporary and future women.

The Ways to Optimize the History Education in Ukrainian Danube Region

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Liliya Tsyganenko

2014-08-01

Full Text Available The history education in the Danube region has a long tradition. In 1940 Akkerman Teachersř Institute (later - Izmail State Pedagogical Institute opened the Faculty of History, which lasted until 1950. Revival of the history education in the region occurred in 1991, when at the college, within the Faculty of Ukrainian Philology was resumed training of the historical profile. As an independent faculty of the University the Department of History existed from 2001 to 2011. Demographic problems, poor funding, remoteness from major research centers, the lack of historical perspective of the scientific projects call into question the ability to save in Izmail University the training center for historians of the region. Today there is an urgent need to optimize the approaches and principles of the organization of history education in the Danube region, which should be based on the application of scientific research in the educational process, expanding European integration approaches, joint historical research, frank discussion on relevant and topical issues of the past Bessarabia. As well as the creation by the scientists of Ukraine, Romania, Bulgaria, Moldova joint history textbooks of the Danube region.

Total Factor Productivity, Demographic Traits and ICT: Empirical Analysis for Asia

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Bilal MEHMOOD

2014-01-01

Full Text Available This paper advances a model to explain the total factor productivity in Asian countries, most of which are labor surplus and are endowed with substantial human capital. Such promising demographic potentials are considered as complementary factors to use of Information and Communication Technology (ICT. Population with such favorable demographic traits and access to ICT results in higher Total factor productivity (TFP. We call this as Demo-Tech-TFP Model and is tested by using data for 2000-2010 of 24 Asian countries. Econometric concerns like presence of endogenous and/or predetermined covariates and small time-series and cross-sectional dimensions of panel dataset are tackled by using System Generalized Method of Moments (SYS-GMM. Results show considerable support for the Demo-Tech-TFP hypothesis. Need is to design such models that suit the local demography and patterns of technological diffusion currently taking place in developing countries.

Towards a History of e-Ducation? Exploring the Possibilities of Digital Humanities for the History of Education

Science.gov (United States)

Van Ruyskensvelde, Sarah

2014-01-01

In the past few years, worries about decreasing jobs or even the possible disappearance of the history of education as a field of study have frequently surfaced. Hence, the question arises as to whether the history of education, as a field of study, has a future--or is it, as many authors have remarked, in danger? This article starts from the idea…

5 CFR 841.404 - Demographic factors.

Science.gov (United States)

2010-01-01

... 5 Administrative Personnel 2 2010-01-01 2010-01-01 false Demographic factors. 841.404 Section 841.404 Administrative Personnel OFFICE OF PERSONNEL MANAGEMENT (CONTINUED) CIVIL SERVICE REGULATIONS (CONTINUED) FEDERAL EMPLOYEES RETIREMENT SYSTEM-GENERAL ADMINISTRATION Government Costs § 841.404 Demographic...

Patterns of variation at Ustilago maydis virulence clusters 2A and 19A largely reflect the demographic history of its populations.

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Ronny Kellner

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

Changing demographics

International Nuclear Information System (INIS)

Vetter, B.M.

1991-01-01

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

A Human Rights and History Education Model for Teaching about Historical Events of Mass Violence: The 1947 British India Partition

Science.gov (United States)

Chhabra, Meenakshi

2017-01-01

This article examines singular historical narratives of the 1947 British India Partition in four history textbooks from India, Pakistan, Bangladesh, and Britain, respectively. Drawing on analysis and work in the field, this study proposes a seven-module "integrated snail model" with a human rights orientation that can be applied to…

Mapping populations at risk: improving spatial demographic data for infectious disease modeling and metric derivation

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Tatem Andrew J

2012-05-01

Full Text Available Abstract The use of Global Positioning Systems (GPS and Geographical Information Systems (GIS in disease surveys and reporting is becoming increasingly routine, enabling a better understanding of spatial epidemiology and the improvement of surveillance and control strategies. In turn, the greater availability of spatially referenced epidemiological data is driving the rapid expansion of disease mapping and spatial modeling methods, which are becoming increasingly detailed and sophisticated, with rigorous handling of uncertainties. This expansion has, however, not been matched by advancements in the development of spatial datasets of human population distribution that accompany disease maps or spatial models. Where risks are heterogeneous across population groups or space or dependent on transmission between individuals, spatial data on human population distributions and demographic structures are required to estimate infectious disease risks, burdens, and dynamics. The disease impact in terms of morbidity, mortality, and speed of spread varies substantially with demographic profiles, so that identifying the most exposed or affected populations becomes a key aspect of planning and targeting interventions. Subnational breakdowns of population counts by age and sex are routinely collected during national censuses and maintained in finer detail within microcensus data. Moreover, demographic and health surveys continue to collect representative and contemporary samples from clusters of communities in low-income countries where census data may be less detailed and not collected regularly. Together, these freely available datasets form a rich resource for quantifying and understanding the spatial variations in the sizes and distributions of those most at risk of disease in low income regions, yet at present, they remain unconnected data scattered across national statistical offices and websites. In this paper we discuss the deficiencies of existing

Climate Variability and Human Migration in the Netherlands, 1865–1937

Science.gov (United States)

Jennings, Julia A.; Gray, Clark L.

2014-01-01

Human migration is frequently cited as a potential social outcome of climate change and variability, and these effects are often assumed to be stronger in the past when economies were less developed and markets more localized. Yet, few studies have used historical data to test the relationship between climate and migration directly. In addition, the results of recent studies that link demographic and climate data are not consistent with conventional narratives of displacement responses. Using longitudinal individual-level demographic data from the Historical Sample of the Netherlands (HSN) and climate data that cover the same period, we examine the effects of climate variability on migration using event history models. Only internal moves in the later period and for certain social groups are associated with negative climate conditions, and the strength and direction of the observed effects change over time. International moves decrease with extreme rainfall, suggesting that the complex relationships between climate and migration that have been observed for contemporary populations extend into the nineteenth century. PMID:25937689

Family history of mood disorder and characteristics of major depressive disorder: a STAR*D (sequenced treatment alternatives to relieve depression) study.

Science.gov (United States)

Nierenberg, Andrew A; Trivedi, Madhukar H; Fava, Maurizio; Biggs, Melanie M; Shores-Wilson, Kathy; Wisniewski, Stephen R; Balasubramani, G K; Rush, A John

2007-01-01

Clinicians routinely ask patients with major depressive disorder (MDD) about their family history. It is unknown, however, if patients who report a positive family history differ from those who do not. This study compared the demographic and clinical features of a large cohort of treatment-seeking outpatients with non-psychotic MDD who reported that they did or did not have at least one first-degree relative who had either MDD or bipolar disorder. Subjects were recruited for the STAR( *)D multicenter trial. Differences in demographic and clinical features for patients with and without a family history of mood disorders were assessed after correcting for age, sex, race, and ethnicity. Patients with a family history of mood disorder (n=2265; 56.5%) were more frequently women and had an earlier age of onset of depression, as compared to those without such a history (n=1740; 43.5%). No meaningful differences were found in depressive symptoms, severity, recurrence, depressive subtype, or daily function. Women were twice as likely as men to report a positive family history of mood disorder, and a positive family history was associated with younger age of onset of MDD in the proband. Consistent with prior research, early age of onset appears to define a familial and, by extension, genetic subtype of major depressive disorder.

Demographics in Astronomy and Astrophysics

Science.gov (United States)

Ulvestad, James S.

2011-05-01

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

Relationship Between Pelvic Organ Prolapse and Non-Human Papillomavirus Pap Smear Abnormalities.

Science.gov (United States)

Menhaji, Kimia; Harvie, Heidi S; Cheston, Emily; Levin, Pamela J; Arya, Lily A; Andy, Uduak U

2017-07-13

The aim of this study was to determine the association between pelvic organ prolapse (POP) and non-human papillomavirus (HPV) Papanicolaou (Pap) smear abnormalities. This was a retrospective cohort study of women aged 40 to 70 years who presented for consultation at our institution between 2010 and 2015 and had results of a Pap smear and HPV test available within 5 years of their visit. We extracted demographic information, medical and social history, Pap smear, and HPV results from the electronic medical record. Associations between the presence of POP and non-HPV Pap smear abnormalities were estimated using univariable and multivariable analyses. We reviewed 1590 charts and excluded 980 women, leaving 610 women in the study: 183 with POP and 427 without POP. Women with POP were significantly older (58.2 ± 7.2 vs 55.6 ± 6.6, P 10 year) history of abnormal Pap smear (24.0% vs 14.8%, P women with POP.

Is there a Demographic Time-bomb?

DEFF Research Database (Denmark)

Greve, Bent

2006-01-01

The article discuss whether the demographic transition in Europe will have any impact on the future of the European welfare states......The article discuss whether the demographic transition in Europe will have any impact on the future of the European welfare states...

Introduction: The Humanities and the Sciences.

Science.gov (United States)

Bod, Rens; Kursell, Julia

2015-06-01

The humanities and the sciences have a strongly connected history, yet their histories continue to be written separately. Although the scope of the history of science has undergone a tremendous broadening during the past few decades, scholars of the history of the humanities and the history of science still seem to belong to two separate cultures that have endured through the past century. This Focus section explores what common ground would enable a study of the histories of the humanities and the sciences to investigate their shared epistemic objects, virtues, values, methods, and practices.

An evaluation of the relations between flow regime components, stream characteristics, species traits and meta-demographic rates of warmwater stream fishes: Implications for aquatic resource management

Science.gov (United States)

Peterson, James T.; Shea, C.P.

2015-01-01

Fishery biologists are increasingly recognizing the importance of considering the dynamic nature of streams when developing streamflow policies. Such approaches require information on how flow regimes influence the physical environment and how those factors, in turn, affect species-specific demographic rates. A more cost-effective alternative could be the use of dynamic occupancy models to predict how species are likely to respond to changes in flow. To appraise the efficacy of this approach, we evaluated relative support for hypothesized effects of seasonal streamflow components, stream channel characteristics, and fish species traits on local extinction, colonization, and recruitment (meta-demographic rates) of stream fishes. We used 4 years of seasonal fish collection data from 23 streams to fit multistate, multiseason occupancy models for 42 fish species in the lower Flint River Basin, Georgia. Modelling results suggested that meta-demographic rates were influenced by streamflows, particularly short-term (10-day) flows. Flow effects on meta-demographic rates also varied with stream size, channel morphology, and fish species traits. Small-bodied species with generalized life-history characteristics were more resilient to flow variability than large-bodied species with specialized life-history characteristics. Using this approach, we simplified the modelling framework, thereby facilitating the development of dynamic, spatially explicit evaluations of the ecological consequences of water resource development activities over broad geographic areas. Published 2014. This article is a U.S. Government work and is in the public domain in the USA.

Fertility in the Age of Demographic Maturity: An Essay

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Anatole Romaniuk

2010-01-01

Full Text Available As humanity is moving into a new age of its demographic evolution, I call it demographic maturity, the emerging demographic configurations – generational sub-replacement fertility, advanced aging and potential population implosion – call for new ways of thinking about population and new policy approaches. While we live longer and healthier, we also reproduce less and less. We are stuck in a culture of low fertility. The strong motivations for foregoing motherhood are financial: a two-salary wage is better than one even for the higher middle class. No less important is the woman’s financial independence in a societal environment where marriage as an institution is under considerable stress. Motherhood is to be rewarded adequately for its highly important social role and it has to be sufficient to reassure potential mothers of their financial concerns. What is required is a more balanced resource allocation between production and reproduction. The old welfare type hand-outs like child bonuses do not work. Societies, particularly the rich, ought to realize that to raise fertility, even to generational replacement level, not only is a much greater financial effort called for but some of the tenants of the liberal economy need to be put into question to make room for social concerns such a renewal of generations, if they want to survive as national entities. This essay advocates a stationary population as the best response to challenges such as ecological health, national identity and cohesion, and possibly world peace.

21 CFR 820.184 - Device history record.

Science.gov (United States)

2010-04-01

... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Device history record. 820.184 Section 820.184 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES QUALITY SYSTEM REGULATION Records § 820.184 Device history record. Each manufacturer shall...

History of the seronegative spondyloarthropathies

International Nuclear Information System (INIS)

Iglesias Gamarra, Antonio; Valle O, Rafael; Restrepo Suarez, Jose Felix

2004-01-01

In this paper we made an extensive and real compile about the history of spondyloarthropathies, since the early study of mammalian skeletons until the human being. Several authors demonstrated the presence of these diseases in skeletons from 3000 years BC. We discuss about the possible African or European origin of the spondyloarthropathies, the history about the firsts clinical, radiological and scintigraphic descriptions, the extra-articular findings, the family cases, and their treatment

History and Principles of Humanitarian Action

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Heather RYSABACK-SMITH

2015-10-01

Full Text Available SUMMARY: Humanitarian aid has been present in some form throughout human history, yet the modern concept of humanitarian aid has only truly emerged since the later half of the 20th century. Through a complex progression of world events and largely brought about in response to armed conflict, modern humanitarian aid is provided by a multitude of organizations and actors. The purpose of this chapter is to provide a brief overview of the history of humanitarian action, a review of the principles of humanitarian aid and an overview of the major documents which delineate those principles. Keywords: Humanitarian aid, human rights

The Genetic Architecture Underlying the Evolution of a Rare Piscivorous Life History Form in Brown Trout after Secondary Contact and Strong Introgression

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Arne Jacobs

2018-05-01

Full Text Available Identifying the genetic basis underlying phenotypic divergence and reproductive isolation is a longstanding problem in evolutionary biology. Genetic signals of adaptation and reproductive isolation are often confounded by a wide range of factors, such as variation in demographic history or genomic features. Brown trout (Salmo trutta in the Loch Maree catchment, Scotland, exhibit reproductively isolated divergent life history morphs, including a rare piscivorous (ferox life history form displaying larger body size, greater longevity and delayed maturation compared to sympatric benthivorous brown trout. Using a dataset of 16,066 SNPs, we analyzed the evolutionary history and genetic architecture underlying this divergence. We found that ferox trout and benthivorous brown trout most likely evolved after recent secondary contact of two distinct glacial lineages, and identified 33 genomic outlier windows across the genome, of which several have most likely formed through selection. We further identified twelve candidate genes and biological pathways related to growth, development and immune response potentially underpinning the observed phenotypic differences. The identification of clear genomic signals divergent between life history phenotypes and potentially linked to reproductive isolation, through size assortative mating, as well as the identification of the underlying demographic history, highlights the power of genomic studies of young species pairs for understanding the factors shaping genetic differentiation.

Human locomotion on ice: the evolution of ice-skating energetics through history.

Science.gov (United States)

Formenti, Federico; Minetti, Alberto E

2007-05-01

More than 3000 years ago, peoples living in the cold North European regions started developing tools such as ice skates that allowed them to travel on frozen lakes. We show here which technical and technological changes determined the main steps in the evolution of ice-skating performance over its long history. An in-depth historical research helped identify the skates displaying significantly different features from previous models and that could consequently determine a better performance in terms of speed and energy demand. Five pairs of ice skates were tested, from the bone-skates, dated about 1800 BC, to modern ones. This paper provides evidence for the fact that the metabolic cost of locomotion on ice decreased dramatically through history, the metabolic cost of modern ice-skating being only 25% of that associated with the use of bone-skates. Moreover, for the same metabolic power, nowadays skaters can achieve speeds four times higher than their ancestors could. In the range of speeds considered, the cost of travelling on ice was speed independent for each skate model, as for running. This latter finding, combined with the accepted relationship between time of exhaustion and the sustainable fraction of metabolic power, gives the opportunity to estimate the maximum skating speed according to the distance travelled. Ice skates were probably the first human powered locomotion tools to take the maximum advantage from the biomechanical properties of the muscular system: even when travelling at relatively high speeds, the skating movement pattern required muscles to shorten slowly so that they could also develop a considerable amount of force.

Correlation between demographic characteristics, cognitive functioning and functional independence in stroke patients

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Arsić Slađana

2016-01-01

Full Text Available Introduction. It has been assumed that there is causality of the achieved level of functional independence with the degree of preservation of cognitive function in stroke patients. Demographic characteristics may be important for monitoring the achieved level of functional independence. Objective. The aim of this study was to examine the relationship of demographic characteristics and functional independence in regard to the level of cognitive impairment in stroke patients. Methods. The study included 50 stroke patients after rehabilitation, as well as age- and gender-matched 50 subjects selected randomly, according to the demographic characteristics of the studied sample, who in their medical history had no neurological disorders. For the assessment of functional independence, the Functional Independence Measure (FIM test was used. The general cognition was estimated by the Mini-Mental State Examination (MMSE test. The statistical analyses included the Mann-Whitney test, for two independent samples, measures of canonical correlation, and χ2 test. Results. There was a statistically significant difference between the groups in relation to risk factors, hypertension and diabetes mellitus type II (p<0.001; There was a statistically significant difference within the groups in relation to the cognitive impairment in all the examined demographic characteristics (p<0.001; the differences within the groups in relation to the cognitive impairment are present on all subscales of the FIM test (p<0.05; the differences within the groups in relation to handedness, hemiparesis, show that mild cognitive impairment is more common among left hemiparesis, while a more severe one is more common among right-sided hemiparesis (p<0.05; More severe cognitive impairment is common among women, the elderly and in persons with lower education (p<0.05. Conclusion. By prevention of risk factors, and prevention of possible cognitive impairment, consequences of stroke can be

Social demographic change and autism.

Science.gov (United States)

Liu, Kayuet; Zerubavel, Noam; Bearman, Peter

2010-05-01

Parental age at child's birth--which has increased for U.S. children in the 1992-2000 birth cohorts--is strongly associated with an increased risk of autism. By turning a social demographic lens on the historical patterning of concordance among twin pairs, we identify a central mechanism for this association: de novo mutations, which are deletions, insertions, and duplications of DNA in the germ cells that are not present in the parents' DNA. Along the way, we show that a demographic eye on the rising prevalence of autism leads to three major discoveries. First, the estimated heritability of autism has been dramatically overstated. Second, heritability estimates can change over remarkably short periods of time because of increases in germ cell mutations. Third, social demographic change can yield genetic changes that, at the population level, combine to contribute to the increased prevalence of autism.

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

Directory of Open Access Journals (Sweden)

Andrew J Dunstan

Full Text Available 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.

Essays on the history of mechanical engineering

CERN Document Server

Genchi, Giuseppe

2016-01-01

This book treats several subjects from the History of Mechanism and Machine Science, and also contains an illustrative presentation of the Museum of Engines and Mechanisms of the University of Palermo, Italy, which houses a collection of various pieces of machinery from the last 150 years. The various sections deal with some eminent scientists of the past, with the history of industrial installations, machinery and transport, with the human inventiveness for mechanical and scientific devices, and with robots and human-driven automata. All chapters have been written by experts in their fields. The volume shows a wide-ranging panorama on the historical progress of scientific and technical knowledge in the past centuries. It will stimulate new research and ideas for those involved in the history of Science and Technology.

Public pensions, family allowances and endogenous demographic change.

Science.gov (United States)

Peters, W

1995-05-01

"A tax-transfer system deals with redistribution a PAYGmong generations and corrective taxation a PAYGt the same time. Since such a policy is a government's task, we take a normative approach and pose the question: Which tax-transfer system should a government apply to maximize social welfare? The framework we consider allows for endogenous demographic aspects...: first, fertility has a great impact on a PAYG [pay-as-you-go] financed pension insurance; and second, through education human capital is accumulated.... We analyzed the optimal extent of a public pension scheme in the presence of external effects of fertility and education on the net domestic product." Pension schemes in Germany and the United States are compared. excerpt

Diagnosing the dangerous demography of manta rays using life history theory

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Nicholas K. Dulvy

2014-05-01

Full Text Available Background. The directed harvest and global trade in the gill plates of mantas, and devil rays, has led to increased fishing pressure and steep population declines in some locations. The slow life history, particularly of the manta rays, is cited as a key reason why such species have little capacity to withstand directed fisheries. Here, we place their life history and demography within the context of other sharks and rays.Methods. Despite the limited availability of data, we use life history theory and comparative analysis to estimate the intrinsic risk of extinction (as indexed by the maximum intrinsic rate of population increase rmax for a typical generic manta ray using a variant of the classic Euler–Lotka demographic model. This model requires only three traits to calculate the maximum intrinsic population growth rate rmax: von Bertalanffy growth rate, annual pup production and age at maturity. To account for the uncertainty in life history parameters, we created plausible parameter ranges and propagate these uncertainties through the model to calculate a distribution of the plausible range of rmax values.Results. The maximum population growth rate rmax of manta ray is most sensitive to the length of the reproductive cycle, and the median rmax of 0.116 year−1 95th percentile [0.089–0.139] is one of the lowest known of the 106 sharks and rays for which we have comparable demographic information.Discussion. In common with other unprotected, unmanaged, high-value large-bodied sharks and rays the combination of very low population growth rates of manta rays, combined with the high value of their gill rakers and the international nature of trade, is highly likely to lead to rapid depletion and potential local extinction unless a rapid conservation management response occurs worldwide. Furthermore, we show that it is possible to derive important insights into the demography extinction risk of data-poor species using well-established life

Diagnosing the dangerous demography of manta rays using life history theory.

Science.gov (United States)

Dulvy, Nicholas K; Pardo, Sebastián A; Simpfendorfer, Colin A; Carlson, John K

2014-01-01

Background. The directed harvest and global trade in the gill plates of mantas, and devil rays, has led to increased fishing pressure and steep population declines in some locations. The slow life history, particularly of the manta rays, is cited as a key reason why such species have little capacity to withstand directed fisheries. Here, we place their life history and demography within the context of other sharks and rays. Methods. Despite the limited availability of data, we use life history theory and comparative analysis to estimate the intrinsic risk of extinction (as indexed by the maximum intrinsic rate of population increase r max) for a typical generic manta ray using a variant of the classic Euler-Lotka demographic model. This model requires only three traits to calculate the maximum intrinsic population growth rate r max: von Bertalanffy growth rate, annual pup production and age at maturity. To account for the uncertainty in life history parameters, we created plausible parameter ranges and propagate these uncertainties through the model to calculate a distribution of the plausible range of r max values. Results. The maximum population growth rate r max of manta ray is most sensitive to the length of the reproductive cycle, and the median r max of 0.116 year(-1) 95th percentile [0.089-0.139] is one of the lowest known of the 106 sharks and rays for which we have comparable demographic information. Discussion. In common with other unprotected, unmanaged, high-value large-bodied sharks and rays the combination of very low population growth rates of manta rays, combined with the high value of their gill rakers and the international nature of trade, is highly likely to lead to rapid depletion and potential local extinction unless a rapid conservation management response occurs worldwide. Furthermore, we show that it is possible to derive important insights into the demography extinction risk of data-poor species using well-established life history theory.

Demographic, reproductive, and dietary determinants of perfluorooctane sulfonic (PFOS) and perfluorooctanoic acid (PFOA) concentrations in human colostrum

NARCIS (Netherlands)

Jusko, T.A.; Oktapodas, M.; Palkovičová Murinová, L.; Babjaková, J.; Verner, M.A.; DeWitt, J.C.; Babinská, K.; Thevenet-Morrison, K.; Čonka, K.; Drobná, B.; Thurston, S.W.; Lawrence, B.P.; Dozier, A.M.; Jarvinen-Seppo, K.M.; Patayová, H.; Trnovec, T.; Legler, J.; Hertz-Picciotto, I.; Lamoree, M.H.

2016-01-01

To determine demographic, reproductive, and maternal dietary factors that predict perfluoroalkyl substance (PFAS) concentrations in breast milk, we measured perfluorooctane sulfonic (PFOS) and perfluorooctanoic acid (PFOA) concentrations, using liquid chromatography-mass spectrometry, in 184

The Tsimane Health and Life History Project: Integrating anthropology and biomedicine.

Science.gov (United States)

Gurven, Michael; Stieglitz, Jonathan; Trumble, Benjamin; Blackwell, Aaron D; Beheim, Bret; Davis, Helen; Hooper, Paul; Kaplan, Hillard

2017-04-01

The Tsimane Health and Life History Project, an integrated bio-behavioral study of the human life course, is designed to test competing hypotheses of human life-history evolution. One aim is to understand the bidirectional connections between life history and social behavior in a high-fertility, kin-based context lacking amenities of modern urban life (e.g. sanitation, banks, electricity). Another aim is to understand how a high pathogen burden influences health and well-being during development and adulthood. A third aim addresses how modernization shapes human life histories and sociality. Here we outline the project's goals, history, and main findings since its inception in 2002. We reflect on the implications of current findings and highlight the need for more coordinated ethnographic and biomedical study of contemporary nonindustrial populations to address broad questions that can situate evolutionary anthropology in a key position within the social and life sciences. © 2017 The Authors Evolutionary Anthropology: Issues, News, and Reviews Published by Wiley Periodicals, Inc.

The Autumn Ghost : the history of polioepidemics in Sweden

OpenAIRE

Axelsson, Per

2004-01-01

Polio epidemics appeared in Sweden in 1881 and at the turn of the 20th century the disease became an annual feature in the epidemiological pattern. Due to vaccination starting in 1957 epidemics ceased to exist in Sweden around 1965. This thesis deals with the history polio epidemics in Sweden, 1880-1965 and studies the demographical influence of polio, how the medical authorities investigated and tried to combat it, and the care of those who contracted the disease. A study of polio mortality ...

IUTAM a short history

CERN Document Server

Juhasz, Stephen

2016-01-01

This book presents extensive information related to the history of IUTAM. The initial chapters focus on IUTAM’s history and selected organizational aspects. Subsequent chapters provide extensive data and statistics, while the closing section showcases photos from all periods of the Union’s history. The history of IUTAM, the International Union on Theoretical and Applied Mechanics, began at a conference in 1922 in Innsbruck, Austria, where von Kármán put forward the idea of an international congress including the whole domain of applied mechanics. In 1946 IUTAM was then formally launched in Paris/France. IUTAM has since time organized more than 24 world congresses and 380 symposia, representing all fields of mechanics and highlighting advances by prominent international researchers. The efforts of IUTAM and its about 50 member countries serve to promote the mechanical sciences and the advancement of human society, addressing many key challenges. In this context, IUTAM preserves important traditions while...

76 FR 28074 - Notice of Inventory Completion: Utah Museum of Natural History, Salt Lake City, UT

Science.gov (United States)

2011-05-13

... of the Utah Museum of Natural History, Salt Lake City, UT. The human remains were removed from Snow.... A detailed assessment of the human remains was made by the Utah Museum of Natural History... with the human remains should contact Duncan Metcalfe, Utah Museum of Natural History, 1390 E...

Demographic outcomes of diverse migration strategies assessed in a metapopulation of tundra swans.

Science.gov (United States)

Ely, Craig R; Meixell, Brandt W

2016-01-01

Migration is a prominent aspect of the life history of many avian species, but the demographic consequences of variable migration strategies have only infrequently been investigated, and rarely when using modern technological and analytical methods for assessing survival, movement patterns, and long-term productivity in the context of life history theory. We monitored the fates of 50 satellite-implanted tundra swans (Cygnus columbianus) over 4 years from five disparate breeding areas in Alaska, and used known-fate analyses to estimate monthly survival probability relative to migration distance, breeding area, migratory flyway, breeding status, and age. We specifically tested whether migratory birds face a trade-off, whereby long-distance migrants realize higher survival rates at the cost of lower productivity because of reduced time on breeding areas relative to birds that migrate shorter distances and spend more time on breeding areas. Annual migration distances varied significantly among breeding areas (1020 to 12720 km), and were strongly negatively correlated with time spent on breeding areas (r = -0.986). Estimates of annual survival probability varied by wintering area (Pacific coast, Alaska Peninsula, and Eastern seaboard) and ranged from 0.79 (95%CI: 0.70-0.88) to 1.0, depending on criteria used to discern mortalities from radio failures. We did not find evidence for a linear relationship between migration distance and survival as swans from the breeding areas with the shortest and longest migration distances had the highest survival probabilities. Survival was lower in the first year post-marking than in subsequent years, but there was not support for seasonal differences in survival. Productivity varied among breeding populations and was generally inversely correlated to survival, but not migration distance or time spent on breeding areas. Tundra swans conformed to a major tenet of life history theory, as populations with the highest survival

[Recent demographic trends in Turkey].

Science.gov (United States)

Behar, C

1993-01-01

Coverage of Turkey's vital registration system remains incomplete, and it cannot yet be used to measure annual population changes. Data and demographic indices based on the 1990 census and the 1989 National Demographic Survey are the most recent available. Turkey's population in 1990 was 56 million. The proportion urban increased to 59% from 49.2% in 1980. Nearly 35% of the population was under 15 years old, and the median age was 21.6 for males and 22.3 for females. The average age at first marriage in 1989 was 24.8 for men and 21.8 for women. Mortality has been in continuous decline. The crude death rate dropped from 16.4/1000 in 1960-65 to slightly under 8 in 1989. Life expectancy at birth was 63.3 for men and 66 for women. The infant mortality rate declined from 166 in 1965-70 to 85 in 1989. Rural or urban residence and maternal educational level were the most significant determinants of infant mortality differentials. Turkey's total fertility rate declined from 6.2 in 1960 to 4.3 in 1978 and 3.4 in 1988-89. The crude birth rate declined from around 40/1000 in 1968 to under 28/1000 in 1989. Fertility began to decline in the last third of the nineteenth century in Istanbul and other large cities of the Ottoman Empire. Istanbul's total fertility rate was a relatively low 3.9 even before World War I. Turkey adopted a policy to slow demographic growth in the mid 1960s, and family planning activities were supported by nongovernmental organizations. The direct impact of these policies on demographic behavior appears to have been somewhat limited, and the use of traditional methods of birth limitation remains widespread. Abortion was legalized in 1983 and is available at public hospitals. The proportion of married women aged 15-49 who use contraception increased from 38% in 1973 to 63% in 1988. Regional differentials in demographic indices are significant in Turkey, with the Anatolian East and Southeast lagging behind other regions in fertility and mortality decline

Frequency of musculoskeleton health problems and its relation with demographic variables among cherat coal miners district nowshera khyber pukhtunkhwa pakistan

International Nuclear Information System (INIS)

Ishtiaq, M.; Zehan, N.

2014-01-01

The objective was to determine the frequency of musculo-skeleton health problems among the coal miners and to assess the relation of musculo-skeleton with various demographic variables among cherat coal miners of District Nowshera Khyber Pukhtunkhwa Pakistan. Materials and Methods: A cross-sectional study design was conducted between July and December 2014 at the cherat coal mines of District Nowshera. A sample size of 400 was selected through cluster sampling technique, in which the study area was divided into four clusters and then from each cluster 40% coal miners were selected based on simple random technique. There are approximately 80-90 Cherat coal mines in which around 1000 of coal miners are working. Coal miner's having more than one year of coal mining job were included in the study while those with less than one year or having any pathological problems were excluded from the study population. Field visits were conducted to collect relevant data from the study areas. The structured pretested questionnaire was used to collect data regarding history of musculo-skeleton problems and was evaluated with the selected demographic variables like age, duration of coal mining job, job satisfaction, and previous history of mine injuries. Results: Our study results showed that approximately 61% of coal miners had history of musculo-skeleton problems. Among those coal miners who gave history of musculo-skeleton problems, 76.64% were due to lack of training, 24.59% to early 1-4 years of coal mining job, 60.23% to less than 30 years of coal miner's age, 75.00% to unsatisfied with job, 83.19% to poor/bad knowledge of mine safety measures; 58.87% for not using personnel protective measures; and 67.62% to positive smoking history while the remaining 32.38 were among non-smokers. Conclusion: The frequency of occupational musculo-skeleton problems among coal miners 61% more and had strong relationship with age, duration of coal mining job, smoking behavior, job satisfaction

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

Directory of Open Access Journals (Sweden)

Holly A Nance

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

Canadian petroleum history bibliography. Release update

Energy Technology Data Exchange (ETDEWEB)

Cass, D.

2010-01-07

The petroleum history bibliography was created over several years as a record dedicated to preserving the history of the Canadian petroleum industry. It comprises a list of more than 5000 publications, including books, theses, films, audio tapes, published articles and stories of the many companies that have come and gone. It aims to include all publications and audio visual products from the Social Sciences and Humanities on company histories, biographies, autobiographies, fiction, poetry and humour. An author index is included. Most government documents are excluded as they are accessible through Library and Archives Canada. This bibliography is an ongoing piece of work, and welcomes any additions relating to the study and preservation of Canadian petroleum industry history.

Experts Networks and the European Commission on Demographic Change

DEFF Research Database (Denmark)

Seabrooke, Leonard; Tsingou, Eleni; Willers, Johann Ole

experts on demographic change. Our findings suggest that on demographic change issues at the EU level, DG EMPL has taken the lead, while DG ECFIN is the secondary actor. Still, internal European Commission dynamics mean that the lead actor on demographic issues has less autonomy in articulating a funded......This paper examines who populates the expert and policy network around demographic change issues in Europe. We examine how competing policy departments in the European Commission Directorates-General (DGs) deal with the issue of Europe’s changing demography, as well as discuss the role of external...... and clear policy position on how to address them. As a consequence, there is little institutional memory and hardly a depository of activity on demographic change. While outside expertise comes primarily from demographers, and other scholars concerned with demographic change, they are primarily an academic...

Maternal risk of breeding failure remained low throughout the demographic transitions in fertility and age at first reproduction in Finland.

Directory of Open Access Journals (Sweden)

Jianghua Liu

Full Text Available Radical declines in fertility and postponement of first reproduction during the recent human demographic transitions have posed a challenge to interpreting human behaviour in evolutionary terms. This challenge has stemmed from insufficient evolutionary insight into individual reproductive decision-making and the rarity of datasets recording individual long-term reproductive success throughout the transitions. We use such data from about 2,000 Finnish mothers (first births: 1880s to 1970s to show that changes in the maternal risk of breeding failure (no offspring raised to adulthood underlay shifts in both fertility and first reproduction. With steady improvements in offspring survival, the expected fertility required to satisfy a low risk of breeding failure became lower and observed maternal fertility subsequently declined through an earlier age at last reproduction. Postponement of the age at first reproduction began when this risk approximated zero-even for mothers starting reproduction late. Interestingly, despite vastly differing fertility rates at different stages of the transitions, the number of offspring successfully raised to breeding per mother remained relatively constant over the period. Our results stress the importance of assessing the long-term success of reproductive strategies by including measures of offspring quality and suggest that avoidance of breeding failure may explain several key features of recent life-history shifts in industrialized societies.

Maternal Risk of Breeding Failure Remained Low throughout the Demographic Transitions in Fertility and Age at First Reproduction in Finland

Science.gov (United States)

Liu, Jianghua; Rotkirch, Anna; Lummaa, Virpi

2012-01-01

Radical declines in fertility and postponement of first reproduction during the recent human demographic transitions have posed a challenge to interpreting human behaviour in evolutionary terms. This challenge has stemmed from insufficient evolutionary insight into individual reproductive decision-making and the rarity of datasets recording individual long-term reproductive success throughout the transitions. We use such data from about 2,000 Finnish mothers (first births: 1880s to 1970s) to show that changes in the maternal risk of breeding failure (no offspring raised to adulthood) underlay shifts in both fertility and first reproduction. With steady improvements in offspring survival, the expected fertility required to satisfy a low risk of breeding failure became lower and observed maternal fertility subsequently declined through an earlier age at last reproduction. Postponement of the age at first reproduction began when this risk approximated zero–even for mothers starting reproduction late. Interestingly, despite vastly differing fertility rates at different stages of the transitions, the number of offspring successfully raised to breeding per mother remained relatively constant over the period. Our results stress the importance of assessing the long-term success of reproductive strategies by including measures of offspring quality and suggest that avoidance of breeding failure may explain several key features of recent life-history shifts in industrialized societies. PMID:22529952

HIV prevalence and demographic determinants of condomless receptive anal intercourse among trans feminine individuals in Beirut, Lebanon.

Science.gov (United States)

Kaplan, Rachel L; McGowan, Justine; Wagner, Glenn J

2016-01-01

Growing evidence suggests increased HIV incidence in the Middle East and North Africa among "key populations." To date, epidemiological data have not accurately included and measured HIV prevalence and risk among trans feminine individuals in the region. Through the lens of the Gender Affirmation Framework, we assessed demographic correlates of risk behaviour and the prevalence of HIV among trans feminine individuals in Lebanon. Long-chain referral sampling was used to recruit 53 participants for completion of a behavioural survey and optional free rapid HIV tests. Data were collected using interviewer-administered questionnaires. A multivariable logistic regression model was used to identify demographic determinants of HIV risk behaviour. Fifty-seven percent of participants reported condomless receptive anal intercourse (CRAI) with male partner(s) in the last three months, 40% of whom reported not knowing the HIV status of the partner(s). Of the participants tested for HIV as part of the study or via self-report, four (10%) were HIV positive; 13 declined HIV testing. Forty percent of the sample had no prior history of HIV testing. A history of trauma such as sexual abuse/assault was reported by almost half of the participants (49%). Sixty-eight percent reported experiencing physical violence and 32% police arrest, because of gender identity or presentation. A staggering 98% reported having experienced gender identity or gender presentation-related discrimination. Sixty-six percent of the sample reported current sex work; sex work was correlated with CRAI but was not significant in multivariate analysis. In regression analysis, "openness"/"outness" about transgender identity at work or school was significantly associated with CRAI. Surprisingly, a history of sexual abuse/assault was negatively correlated with CRAI, suggesting the need for further inquiry. The results of this study provide implications for how to address sexual health among trans feminine

Understanding the Demographic and Health Transition in ...

International Development Research Centre (IDRC) Digital Library (Canada)

23 juin 2009 ... Understanding the Demographic and Health Transition in Developing Countries ... countries comes from analysis of demographic and health survey data. ... Navrongo (Ghana), Matlab (Bangladesh) and Filabavi (Viet Nam) ...

Understanding human DNA sequence variation.

Science.gov (United States)

Kidd, K K; Pakstis, A J; Speed, W C; Kidd, J R

2004-01-01

Over the past century researchers have identified normal genetic variation and studied that variation in diverse human populations to determine the amounts and distributions of that variation. That information is being used to develop an understanding of the demographic histories of the different populations and the species as a whole, among other studies. With the advent of DNA-based markers in the last quarter century, these studies have accelerated. One of the challenges for the next century is to understand that variation. One component of that understanding will be population genetics. We present here examples of many of the ways these new data can be analyzed from a population perspective using results from our laboratory on multiple individual DNA-based polymorphisms, many clustered in haplotypes, studied in multiple populations representing all major geographic regions of the world. These data support an "out of Africa" hypothesis for human dispersal around the world and begin to refine the understanding of population structures and genetic relationships. We are also developing baseline information against which we can compare findings at different loci to aid in the identification of loci subject, now and in the past, to selection (directional or balancing). We do not yet have a comprehensive understanding of the extensive variation in the human genome, but some of that understanding is coming from population genetics.

Endogenous ROS levels in C. elegans under exogenous stress support revision of oxidative stress theory of life-history tradeoffs.

Science.gov (United States)

Smith, Samson W; Latta, Leigh C; Denver, Dee R; Estes, Suzanne

2014-07-24

The oxidative stress theory of life-history tradeoffs states that oxidative stress caused by damaging free radicals directly underpins tradeoffs between reproduction and longevity by altering the allocation of energetic resources between these tasks. We test this theory by characterizing the effects of exogenous oxidative insult and its interaction with thermal stress and diet quality on a suite of life-history traits and correlations in Caenorhabditis elegans nematodes. We also quantify demographic aging rates and endogenous reactive oxygen species (ROS) levels in live animals. Our findings indicate a tradeoff between investment in reproduction and antioxidant defense (somatic maintenance) consistent with theoretical predictions, but correlations between standard life-history traits yield little evidence that oxidative stress generates strict tradeoffs. Increasing oxidative insult, however, shows a strong tendency to uncouple positive phenotypic correlations and, in particular, to reduce the correlation between reproduction and lifespan. We also found that mild oxidative insult results in lower levels of endogenous ROS accompanied by hormetic changes in lifespan, demographic aging, and reproduction that disappear in combined-stress treatments--consistent with the oxidative stress theory of aging. Our findings demonstrate that oxidative stress is a direct contributor to life-history trait variation and that traditional tradeoffs are not necessary to invoke oxidative stress as a mediator of relationships between life-history traits, supporting previous calls for revisions to theory.

Non-human primates avoid the detrimental effects of prenatal androgen exposure in mixed-sex litters: combined demographic, behavioral, and genetic analyses.

Science.gov (United States)

Bradley, Brenda J; Snowdon, Charles T; McGrew, William C; Lawler, Richard R; Guevara, Elaine E; McIntosh, Annick; O'Connor, Timothy

2016-12-01

Producing single versus multiple births has important life history trade-offs, including the potential benefits and risks of sharing a common in utero environment. Sex hormones can diffuse through amniotic fluid and fetal membranes, and females with male littermates risk exposure to high levels of fetal testosterone, which are shown to have masculinizing effects and negative fitness consequences in many mammals. Whereas most primates give birth to single offspring, several New World monkey and strepsirrhine species regularly give birth to small litters. We examined whether neonatal testosterone exposure might be detrimental to females in mixed-sex litters by compiling data from long-term breeding records for seven primate species (Saguinus oedipus; Varecia variegata, Varecia rubra, Microcebus murinis, Mirza coquereli, Cheirogaleus medius, Galago moholi). Litter sex ratios did not differ from the expected 1:2:1 (MM:MF:FF for twins) and 1:2:2:1 (MMM:MMF:MFF:FFF for triplets). Measures of reproductive success, including female survivorship, offspring-survivorship, and inter-birth interval, did not differ between females born in mixed-sex versus all-female litters, indicating that litter-producing non-human primates, unlike humans and rodents, show no signs of detrimental effects from androgen exposure in mixed sex litters. Although we found no evidence for CYP19A1 gene duplications-a hypothesized mechanism for coping with androgen exposure-aromatase protein evolution shows patterns of convergence among litter-producing taxa. That some primates have effectively found a way to circumvent a major cost of multiple births has implications for understanding variation in litter size and life history strategies across mammals. © 2016 Wiley Periodicals, Inc.

Is it the end of history for LWR safety?

International Nuclear Information System (INIS)

Sehgal, Bal Raj

2004-01-01

In this essay a parallel is drawn between the struggle for recognition, which is argued by Fukuyama as the 'motor' of human history and that waged by the LWR safety for the public to recognize the LWR plants as a source of safe nuclear power. The end of history for the ''human struggle for recognition'' as the capitalistic liberal democracy is equated with the ''end of history'' for the LWR safety to provide assurance to the public of termination of a severe accident it ever would occur. It is suggested that we are near ''the end of history'' of the LWR safety for the new-design LWR plants but fall short for the presently-installed plants. The essay bases these suggestions on an examination of the history of nuclear power development in U.S.A., but also considering the more recent regulatory and public acceptance developments in Europe and the rest of the World. (author)

A tale of two epidemics: gender differences in socio-demographic characteristics and sexual behaviors among HIV positive individuals in Mexico City.

Science.gov (United States)

Bautista-Arredondo, Sergio; Servan-Mori, Edson; Beynon, Fenella; González, Andrea; Volkow, Patricia

2015-12-16

To date, the HIV epidemic in Mexico has been concentrated mainly among men who have sex with men, butheterosexual transmission, particularly to women, is increasingly important. This study examine gender differences in socio-demographic characteristics and risk behaviors of HIV positive individuals in Mexico City. We analyzed data from a cross-sectional survey of 1,490 clinic patients (male:female ratio 8:1) with HIV inMexico City in 2010. We examined socio-demographic characteristics, risk behavior, and history of HIV infection.From multivariate non-linear probability (probit) models we calculated predicted probabilities by sex of several outcomes: marginalization, demographic and sexual risk behaviors. Significant differences were found between men and women. Multivariate models suggest that women had lower schooling levels; were less likely to have been employed in the past month and earn more than the minimal wage; more likely to have children, to have been sexually abused, to never have used condoms and to report having been infected by a stable partner. Additionally, women were less likely to report having a partner with a history of migration to the USA and to have engaged in transactional sex. Significant differences exist between men and women with HIV in Mexico City in terms of their socioeconomicand behavioral profiles, which translate into differences in terms of exposure to HIV infection. Women face social and economic vulnerability while men tend to have riskier sexual behavior. Gender issues must be approached in prevention and treatment efforts, using diverse methods to target those most vulnerable and at risk.

Mental Health of People Who Are Going to Marry and Its Relation to Some of Their Demographic Factors

Directory of Open Access Journals (Sweden)

Z. Ghazivakili

2014-05-01

Full Text Available Introduction: Marriage is one of the most important events during an individual's life. Mental health as a component of personal characteristics, are associated with marital satisfaction. considering the role of mental health in a successful marriage, the impact of family health on community mental health, and major role of couples in this regard the present study aimed to determine the Mental health of people who are going to marry and its relation to some of their demographic factors in karaj 2012. Material and Methods: We performed a cross sectional study on the established group of 600 people who attended premarital assessment in a health center. They were selected by convenient sampling method. The data collection instrument was a demographic questionnaire and standardized Goldberge mental health (GHQ-28 questionnaire. The data was analyzed with SPSS/18 using descriptive and inferential statistical methods.(P<0.05 Findings: The mean score of mental health questionnaire was (16/2 ± 9/9. The results also showed that mental health and sex, religion, place of birth, marital history and employment status were significantly related (P<0.05 such that the mental health of men, Shea, born in the village, no history of marriage, and have a permanent job was higher. Conclusion: Recent research results indicate the desirability of mental health in 80.3 percent of in new couples.

History and Structure of Sub-Saharan Populations of Drosophila melanogaster

OpenAIRE

Pool, John E.; Aquadro, Charles F.

2006-01-01

Drosophila melanogaster is an important model organism in evolutionary genetics, yet little is known about the population structure and the demographic history of this species within sub-Saharan Africa, which is thought to contain its ancestral range. We surveyed nucleotide variation at four 1-kb fragments in 240 individual lines representing 21 sub-Saharan and 4 Palearctic population samples of D. melanogaster. In agreement with recent studies, we find a small but significant level of geneti...

Relationship Between Tetanus Antitoxin Titration Level and Vaccination History

Directory of Open Access Journals (Sweden)

Meltem Işıkgöz Taşbakan

2017-12-01

Full Text Available Objectives: We aimed to determine tetanus antitoxin levels and to evaluate their relationship with history of vaccination among patients applying to the outpatient clinics of a University hospital. Methods: A questionnaire including socio-demographic characteristics and tetanus vaccination status was applied and blood samples taken from 218 subjects between 1 and 30 June 2015. Participants were classified into five groups according to their vaccination timing. Results: The mean age of participants was 46.7±15.4 years and 134 (61.5% were women. Tetanus antitoxin levels were found weak positive in 54 (24.8% patients, positive in 44 (20.2% and strong positive in 120 (55.0%. Tetanus antitoxin level positivity was significantly associated with vaccination timing according to history. Among 105 participants who did not remember being vaccinated or who knew they were vaccinated but did not remember the date, 16 (15.2% remembered the vaccination time when their injury, military service and pregnancy were questioned specifically. Antitoxin levels decreased with increasing age independent of gender (0.9-fold increase/year. Conclusion: We found that the booster dose recommended every 10 years was not applied sufficiently. Tetanus vaccination history must be questioned in more detail among people who do not remember/know their vaccination history, with specific questions regarding pregnancy, military service and injury histories.

[WEIGHT GAIN DURING PREGNANCY AND PERINATAL OUTCOMES IN PREGNANT ADOLESCENTS WITH A HISTORY OF SEXUAL ABUSE].

Science.gov (United States)

Sam-Soto, Selene; Sámano, Reyna; Flores-Ramos, Mónica; Rodríguez-Bosch, Mario; García-Salazar, Danae; Hernández-Mohar, Gabriela; García-Espinosa, Verónica

2015-09-01

the purpose of the present study was to describe some perinatal outcomes in two groups of pregnant adolescents: one group with history of sexual abuse and one group without sexual abuse antecedent. we designed an observational, retrolective study. Participants were primigravid adolescents between 10 to 16 years, with a singleton pregnancy, and at least three prenatal medical evaluations. Participants were grouped according to sexual abuse antecedent: 55 adolescents had sexual abuse antecedent, and 110 participants had not sexual abuse antecedent. We obtained the clinical data from medical records: socio-demographic characteristics, sexually transmitted infections, illicit drugs use, pre-gestational body mass index, gestational weight gain, and newborn weight. The data were analyzed using association tests and mean comparisons. the adolescents with sexual abuse history had higher prevalence of human papilloma virus infection. The newborns weight of mothers without sexual abuse antecedent was about 200 grams higher than the newborns of mothers with sexual abuse antecedent (p = 0.002); while the length of the first group was 2 centimeters longer than the length of the newborns on the second group (p = 0.001). Gestational weight increase was 5 kilograms lower in adolescents with sexual abuse antecedent compared to adolescent without the antecedent (p = 0.005). Illicit drug use was similar in the two groups and it was associated to low newborn weight. the sexual abuse antecedent in pregnant adolescents was associated to higher frequency of human papilloma virus infections, lower newborn weight, and lower gestational weight increase on pregnant adolescents. Copyright AULA MEDICA EDICIONES 2014. Published by AULA MEDICA. All rights reserved.

Prevalence and Sociodemographic Determinants of Hypertension History among Women in Reproductive Age in Ghana

Directory of Open Access Journals (Sweden)

Samuel H. Nyarko

2016-01-01

Full Text Available Background. Hypertension is a global health problem. Yet, studies on hypertension rarely focus on women in Ghana. The purpose of this study is to ascertain the prevalence and sociodemographic determinants of hypertension history among Ghanaian women in reproductive age. Methods. This study used data from the 2014 Ghana Demographic and Health Survey. Bivariate and logistic regression analyses were carried out to ascertain the prevalence and determinants of hypertension history among the respondents. Results. The study found that the overall prevalence of hypertension history among the respondents was 7.5%; however, there were vast variations within most of the sociodemographic categories. Age, level of education, marital status, work status, and wealth status had a significant relationship with hypertension history among the respondents. Women in advanced age groups, highly educated, married, and widowed/divorced/separated, nonworking women, and women from wealthy households were at higher risk of having hypertension history. Conclusion. Myriads of sociodemographic factors determine the hypertension history of women in Ghana. It is therefore essential to target medical and psychosocial hypertension interventions at Ghanaian women in the higher risk groups.

Using Remote Sensing, Weather, and Demographic Data to Create Risk Maps for Zika, Dengue, and Chikungunya in Brazil

Science.gov (United States)

Manore, C.; Conrad, J.; Del Valle, S.; Ziemann, A.; Fairchild, G.; Generous, E. N.

2017-12-01

Mosquito-borne diseases such as Zika, dengue, and chikungunya viruses have dynamics coupled to weather, ecology, human infrastructure, socio-economic demographics, and behavior. We use time-varying remote sensing and weather data, along with demographics and ecozones to predict risk through time for Zika, dengue, and chikungunya outbreaks in Brazil. We use distributed lag methods to quantify the lag between outbreaks and weather. Our statistical model indicates that the relationships between the variables are complex, but that quantifying risk is possible with the right data at appropriate spatio-temporal scales.

Burnout in Social Workers Treating Children as Related to Demographic Characteristics, Work Environment, and Social Support

Science.gov (United States)

Hamama, Liat

2012-01-01

This study examined sense of burnout among 126 social workers who directly treat children and adolescents within the human service professions. Burnout was investigated in relation to social workers' demographic characteristics (age, family status, education, and seniority at work), extrinsic and intrinsic work conditions, and social support by…

Mutation Rate Variation is a Primary Determinant of the Distribution of Allele Frequencies in Humans.

Directory of Open Access Journals (Sweden)

Arbel Harpak

2016-12-01

Full Text Available The site frequency spectrum (SFS has long been used to study demographic history and natural selection. Here, we extend this summary by examining the SFS conditional on the alleles found at the same site in other species. We refer to this extension as the "phylogenetically-conditioned SFS" or cSFS. Using recent large-sample data from the Exome Aggregation Consortium (ExAC, combined with primate genome sequences, we find that human variants that occurred independently in closely related primate lineages are at higher frequencies in humans than variants with parallel substitutions in more distant primates. We show that this effect is largely due to sites with elevated mutation rates causing significant departures from the widely-used infinite sites mutation model. Our analysis also suggests substantial variation in mutation rates even among mutations involving the same nucleotide changes. In summary, we show that variable mutation rates are key determinants of the SFS in humans.

Are elder siblings helpers or competitors? Antagonistic fitness effects of sibling interactions in humans

Science.gov (United States)

Nitsch, Aïda; Faurie, Charlotte; Lummaa, Virpi

2013-01-01

Determining the fitness consequences of sibling interactions is pivotal for understanding the evolution of family living, but studies investigating them across lifetime are lacking. We used a large demographic dataset on preindustrial humans from Finland to study the effect of elder siblings on key life-history traits. The presence of elder siblings improved the chances of younger siblings surviving to sexual maturity, suggesting that despite a competition for parental resources, they may help rearing their younger siblings. After reaching sexual maturity however, same-sex elder siblings' presence was associated with reduced reproductive success in the focal individual, indicating the existence of competition among same-sex siblings. Overall, lifetime fitness was reduced by same-sex elder siblings' presence and increased by opposite-sex elder siblings' presence. Our study shows opposite effects of sibling interactions depending on the life-history stage, and highlights the need for using long-term fitness measures to understand the selection pressures acting on sibling interactions. PMID:23173210

Telling Modernization: Three Voices. Life History, Gender and the Discourse of Modernization. Roskilde University Life History Project Paper.

Science.gov (United States)

Anderson, Linda

The relationship between life history, gender, and the discourse of modernization was examined from the perspective of a researcher with extensive experience performing evaluations about modernization within human services in Denmark. Three stories about site-based management in two human service institutionsa youth center and a boarding school…

Estimating demographic parameters from large-scale population genomic data using Approximate Bayesian Computation

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Li Sen

2012-03-01

Full Text Available Abstract Background The Approximate Bayesian Computation (ABC approach has been used to infer demographic parameters for numerous species, including humans. However, most applications of ABC still use limited amounts of data, from a small number of loci, compared to the large amount of genome-wide population-genetic data which have become available in the last few years. Results We evaluated the performance of the ABC approach for three 'population divergence' models - similar to the 'isolation with migration' model - when the data consists of several hundred thousand SNPs typed for multiple individuals by simulating data from known demographic models. The ABC approach was used to infer demographic parameters of interest and we compared the inferred values to the true parameter values that was used to generate hypothetical "observed" data. For all three case models, the ABC approach inferred most demographic parameters quite well with narrow credible intervals, for example, population divergence times and past population sizes, but some parameters were more difficult to infer, such as population sizes at present and migration rates. We compared the ability of different summary statistics to infer demographic parameters, including haplotype and LD based statistics, and found that the accuracy of the parameter estimates can be improved by combining summary statistics that capture different parts of information in the data. Furthermore, our results suggest that poor choices of prior distributions can in some circumstances be detected using ABC. Finally, increasing the amount of data beyond some hundred loci will substantially improve the accuracy of many parameter estimates using ABC. Conclusions We conclude that the ABC approach can accommodate realistic genome-wide population genetic data, which may be difficult to analyze with full likelihood approaches, and that the ABC can provide accurate and precise inference of demographic parameters from

Socio-demographic profile and compliance to Weekly Iron Folic Acid supplementation among adolescent girls in Central Delhi

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Anuradha Chauhan

2015-12-01

Objective: 1. To find out the prevalence of iron deficiency anemia in the study group. 2. To study the various socio-demographic factors associated with anemia. 3. To study the compliance of weekly Iron Folic acid Supplementation (WIFS. Material and Methods: A cross-sectional survey was conducted in an Urban Health Center, in New Delhi. A total of 60 adolescent females (10–19 years old were included in this study. The study was undertaken from Nov 2013 – Dec 2013 (2 months using a pre-tested questionnaire containing items to assess the socio-demographic profile, their medical history and past history. After taking their assent, hemoglobin (Hb was estimated using HemoCue method. Results: The prevalence of anemia was found to be 71.1%. A significant association of presence of anemia was found with lower socio-economic status and non-intake of WIFS. Mean height and weight of subjects with anemia was significantly less in anemic girls than participants without anemia. Significant association of anemia was found with non-consumption of Iron Folic Acid (IFA tablets (χ2 value – 5.3, p value 0.02. Conclusions: A high prevalence of anemia among adolescent females was found, which was higher in the lower socio-economic strata and those not consuming WIFS. Thus there is a need to strengthen the programs for the prevention of anemia among adolescent girls through nutrition education and anemia prophylaxis.

History, Culture, Peace: Rumi Mevlana

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Alina Beatrice Cheşcă

2016-05-01

Full Text Available Along the history, for so many centuries, Rumi Mawlana – perhaps the most loved mystical poet of all times – has been alive and talking to people of all cultures through the language of love, peace, faith and true kindness. This remarkable man has always transcended the boundaries of time, space, race, religion, considering that “Love is the very meaning of creation and life”. It would not be an exaggeration to assert that the history of humankind would have been a paradise if human beings had followed such principles like peace, love and understanding. Rumi Mawlana created a splendid, humanitarian and universal type of art, culture and mentality; his message is God’s message to humankind: friendship, hope, generosity, peace, beauty, in one word: Love and happiness in all forms. Thus, he used his huge poetic talent not only in order to touch people’s hearts, but also to reach the most splendid goal of the human race: that of making people more sensitive to the eternal and most important human values.

Plague in Iran: its history and current status

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Abdolrazagh Hashemi Shahraki

2016-07-01

Full Text Available OBJECTIVES: Plague remains a public health concern worldwide, particularly in old foci. Multiple epidemics of this disease have been recorded throughout the history of Iran. Despite the long-standing history of human plague in Iran, it remains difficult to obtain an accurate overview of the history and current status of plague in Iran. METHODS: In this review, available data and reports on cases and outbreaks of human plague in the past and present in Iran and in neighboring countries were collected, and information was compiled regarding when, where, and how many cases occurred. RESULTS: This paper considers the history of plague in Persia (the predecessor of today’s Iran and has a brief review of plague in countries in the World Health Organization Eastern Mediterranean Region, including a range of countries in the Middle East and North Africa. CONCLUSIONS: Since Iran has experienced outbreaks of plague for several centuries, neighboring countries have reported the disease in recent years, the disease can be silent for decades, and the circulation of Yersinia pestis has been reported among rodents and dogs in western Iran, more attention should be paid to disease monitoring in areas with previously reported human cases and in high-risk regions with previous epizootic and enzootic activity.

Plague in Iran: its history and current status.

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Hashemi Shahraki, Abdolrazagh; Carniel, Elizabeth; Mostafavi, Ehsan

2016-01-01

Plague remains a public health concern worldwide, particularly in old foci. Multiple epidemics of this disease have been recorded throughout the history of Iran. Despite the long-standing history of human plague in Iran, it remains difficult to obtain an accurate overview of the history and current status of plague in Iran. In this review, available data and reports on cases and outbreaks of human plague in the past and present in Iran and in neighboring countries were collected, and information was compiled regarding when, where, and how many cases occurred. This paper considers the history of plague in Persia (the predecessor of today's Iran) and has a brief review of plague in countries in the World Health Organization Eastern Mediterranean Region, including a range of countries in the Middle East and North Africa. Since Iran has experienced outbreaks of plague for several centuries, neighboring countries have reported the disease in recent years, the disease can be silent for decades, and the circulation of Yersinia pestis has been reported among rodents and dogs in western Iran, more attention should be paid to disease monitoring in areas with previously reported human cases and in high-risk regions with previous epizootic and enzootic activity.

Local extinction and recolonization, species effective population size, and modern human origins.

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Eller, Elise; Hawks, John; Relethford, John H

2004-10-01

A primary objection from a population genetics perspective to a multiregional model of modern human origins is that the model posits a large census size, whereas genetic data suggest a small effective population size. The relationship between census size and effective size is complex, but arguments based on an island model of migration show that if the effective population size reflects the number of breeding individuals and the effects of population subdivision, then an effective population size of 10,000 is inconsistent with the census size of 500,000 to 1,000,000 that has been suggested by archeological evidence. However, these models have ignored the effects of population extinction and recolonization, which increase the expected variance among demes and reduce the inbreeding effective population size. Using models developed for population extinction and recolonization, we show that a large census size consistent with the multiregional model can be reconciled with an effective population size of 10,000, but genetic variation among demes must be high, reflecting low interdeme migration rates and a colonization process that involves a small number of colonists or kin-structured colonization. Ethnographic and archeological evidence is insufficient to determine whether such demographic conditions existed among Pleistocene human populations, and further work needs to be done. More realistic models that incorporate isolation by distance and heterogeneity in extinction rates and effective deme sizes also need to be developed. However, if true, a process of population extinction and recolonization has interesting implications for human demographic history.

Relation Between Demographic Factors And Hospitalization In ...

African Journals Online (AJOL)

Relation Between Demographic Factors And Hospitalization In Patients With Gastrointestinal Disorders, Using Quantail Regression Analysis. ... East African Journal of Public Health ... Objective: The aim of this study is to investigate relation between demographic factors and hospitalization in gastrointestinal disorders.

For a history of the histories of Portuguese cinema

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Paulo Cunha

2016-02-01

Full Text Available For decades, the history of Portuguese cinema was made without historians or academics in the social sciences and humanities, but made by curious, enthusiasts and writers who were committed to the object itself. It was therefore that these early writings, although an essential role in collecting and inventariações sources, promoted the creation of myths, more implicitly or explicitly manipulated the past of Portuguese cinema and conditioned its historic narrative.This thematic dossier brings together four essays that analyze and reflect on different ideas and conceptions of Portuguese Cinema which have been outlined in stocks, texts and films over the decades. The purpose of this dossier is not to answer questions, but take advantage of them to review preconceived ideas and to launch reading hypotheses to classic and current issues in the history of Portuguese cinema.

Biographical and demographical variables as moderators in the prediction of turnover intentions

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Janine du Plooy

2013-04-01

Full Text Available Orientation: The aim of the study was to explore the possible moderation effects of biographical and demographical variables on a prediction model of turnover intention (TI. Research purpose: The main purpose of the study was to determine how biographical and demographical variables have an impact on predictors of turnover intentions. Motivation for the study: Twenty-first century organisations face significant challenges in the management of talent and human capital. One in particular is voluntary employee turnover and the lack of appropriate business models to track this process. Research design, approach, and method: A secondary data analysis (SDA was performed in a quantitative research tradition on the cross-sectional survey sample (n = 2429. Data were collected from a large South African Information and Communication Technologies (ICT sector company (N = 23 134. Main findings: The results of the study confirmed significant moderation effects regarding race, age, and marital status in the prediction equations of TIs. Practical and managerial implications: Practical implications of the study suggested increased understanding of workforce diversity effects within the human resource (HR value chain, with resultant evidence-based, employee retention strategies and interventions. Issues concerning talent management could also be addressed. Contribution and value-add: The study described in this article took Industrial/Organisational (I/O psychological concepts and linked them in unique combinations to establish better predictive validity of a more comprehensive turnover intentions model.

Impacts of biogeographic history and marginal population genetics on species range limits: a case study of Liriodendron chinense.

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Yang, Aihong; Dick, Christopher W; Yao, Xiaohong; Huang, Hongwen

2016-05-10

Species ranges are influenced by past climate oscillations, geographical constraints, and adaptive potential to colonize novel habitats at range limits. This study used Liriodendron chinense, an important temperate Asian tree species, as a model system to evaluate the roles of biogeographic history and marginal population genetics in determining range limits. We examined the demographic history and genetic diversity of 29 L. chinense populations using both chloroplast and nuclear microsatellite loci. Significant phylogeographic structure was recovered with haplotype clusters coinciding with major mountain regions. Long-term demographical stability was suggested by mismatch distribution analyses, neutrality tests, and ecological niche models (ENM) and suggested the existence of LGM refuges within mountain regions. Differences in genetic diversity between central and marginal populations were not significant for either genomic region. However, asymmetrical gene flow was inferred from central populations to marginal populations, which could potentially limit range adaptation and expansion of L. chinense.

Military History: A Selected Bibliography

National Research Council Canada - National Science Library

Murray, Williamson

2003-01-01

... and comprehension of that terrible, yet intriguing, human phenomenon that is war. JAWP is making it available to those individuals in DoD and the Services who feel that history can shed light on the problems they confront today...

Teaching History in a Post-Industrial Age

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Bianchetti, Ann

2004-01-01

As a social studies teacher, the author emphasizes the story of history (sticking to the facts as much as they are known) and the human qualities of the players. Middle school kids are in the throes of exploring self-identity and attempting to define their worlds. They love drama, and history provides plenty of it. The author finds that teaching…

Exploring the socio-demographic differences on psychological career meta-capacities and retention-related dispositions

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Rebecca Tladinyane

2015-08-01

Full Text Available The aim of this study was to better understand socio-demographic differences of individuals in terms of their psychological career meta-capacities (measured by the Psychological Career Resources Inventory and their retention related dispositions construct variables ((measured by the Utrecht Work Engagement Scale and Organisation-Related Commitment Scale. A quantitative survey was conducted involving a non-probability purposive sample of predominantly black females employed at managerial and staff levels (N = 318 in the field of industrial and organisational psychology. An independent-samples t-test indicated significant differences between the various socio-demographic groups in regard to the measured variables. The findings contribute new knowledge that may be used to inform human resource career development practices concerned with the retention of particularly female employees in South African service industry

History of Smoking and Postcessation Weight Gain among Weight Loss Surgery Candidates

OpenAIRE

Levine, Michele D.; Kalarchian, Melissa A.; Courcoulas, Anita P.; Wisinski, Meghan S.C.; Marcus, Marsha D.

2007-01-01

Smoking cessation often results in weight gain. Although smoking cessation frequently is recommended to patients presenting for weight loss surgery (WLS), the relationship between smoking cessation and weight gain among WLS candidates is poorly understood. Thus, we sought to document the history and prevalence of smoking and smoking-related weight gain among WLS candidates. Subjects (N = 67) presenting for bariatric surgery provided demographic information, were interviewed about smoking, and...