Lyme disease risk in southern California: abiotic and environmental drivers of Ixodes pacificus (Acari: Ixodidae) density and infection prevalence with Borrelia burgdorferi.

PubMed

MacDonald, Andrew J; Hyon, David W; Brewington, John B; O'Connor, Kerry E; Swei, Andrea; Briggs, Cheryl J

2017-01-05

Tick-borne diseases, particularly Lyme disease, are emerging across the northern hemisphere. In order to manage emerging diseases and predict where emergence will likely occur, it is necessary to understand the factors influencing the distribution, abundance and infection prevalence of vector species. In North America, Lyme disease is the most common vector-borne disease and is transmitted by blacklegged ticks. This study aimed to explore the abiotic and environmental drivers of density and infection prevalence of western blacklegged ticks (Ixodes pacificus) in southern California, an understudied and densely populated region of North America. Over the course of this two-year study, densities of I. pacificus adults were consistently positively associated with host availability for juvenile ticks and dense oak woodland habitat. Densities of nymphal and larval I. pacificus, on the other hand were primarily predicted by host availability for juvenile ticks in the first year of the study, and by habitat characteristics such as dense leaf litter in the second year. Infection with the causative agent of Lyme disease, Borrelia burgdorferi (sensu stricto), and related spirochetes was not predicted by the abiotic conditions promoting I. pacificus populations, but rather by diversity of the tick community, and in particular by the presence of two Ixodes tick species that do not generally feed on humans (Ixodes spinipalpis and Ixodes peromysci). Borrelia spp. infection was not detected in the I. pacificus populations sampled, but was detected in other vector species that may maintain enzootic transmission of the pathogen on the landscape. This study identified dense oak woodlands as high-risk habitats for I. pacificus tick encounter in southern California. The shift in relative importance of host availability to habitat characteristics in predicting juvenile tick abundance occurred as California's historic drought intensified, suggesting that habitat providing suitable microclimates for tick survivorship became centrally important to patterns of abundance in the face of deleterious abiotic conditions. These results underscore the need for further investigation of the effects of climate change on tick-borne disease in California. Finally, despite low risk of human Lyme disease infection posed by I. pacificus in southern California, evidence of infection was found in other tick species, suggesting that enzootic transmission of tick-borne borreliae may be occurring in southern California, and involve parallel enzootic cycles with other tick and host species but not necessarily humans.

Human and cattle population changes in deltaic West Bengal, India between 1977-1987

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

Odend'hal, S.

1988-03-01

In 1967-1970, 3.81 km/sup 2/ of a densely populated deltaic area of Hooghly district in West Bengal, India was intensively studied. This same area was resurveyed in 1977 and 1987. From 1977-1987, the human population has increased 10.1%, while the number of households has increased 25%. The total number of children below 10 years of age has diminished. The cattle have increased 26.5%. The number of working-age male cattle has dropped significantly with reliance, primarily on hand tractor power for field cultivation. The number of female cattle has increased substantially. Artificial insemination and the use of temperate breeds of bullsmore » have had an obvious impact. Improvements in the general environment were observed.« less

Fishery-independent data reveal negative effect of human population density on Caribbean predatory fish communities.

PubMed

Stallings, Christopher D

2009-01-01

Understanding the current status of predatory fish communities, and the effects fishing has on them, is vitally important information for management. However, data are often insufficient at region-wide scales to assess the effects of extraction in coral reef ecosystems of developing nations. Here, I overcome this difficulty by using a publicly accessible, fisheries-independent database to provide a broad scale, comprehensive analysis of human impacts on predatory reef fish communities across the greater Caribbean region. Specifically, this study analyzed presence and diversity of predatory reef fishes over a gradient of human population density. Across the region, as human population density increases, presence of large-bodied fishes declines, and fish communities become dominated by a few smaller-bodied species. Complete disappearance of several large-bodied fishes indicates ecological and local extinctions have occurred in some densely populated areas. These findings fill a fundamentally important gap in our knowledge of the ecosystem effects of artisanal fisheries in developing nations, and provide support for multiple approaches to data collection where they are commonly unavailable.

Fishery-Independent Data Reveal Negative Effect of Human Population Density on Caribbean Predatory Fish Communities

PubMed Central

Stallings, Christopher D.

2009-01-01

Background Understanding the current status of predatory fish communities, and the effects fishing has on them, is vitally important information for management. However, data are often insufficient at region-wide scales to assess the effects of extraction in coral reef ecosystems of developing nations. Methodology/Principal Findings Here, I overcome this difficulty by using a publicly accessible, fisheries-independent database to provide a broad scale, comprehensive analysis of human impacts on predatory reef fish communities across the greater Caribbean region. Specifically, this study analyzed presence and diversity of predatory reef fishes over a gradient of human population density. Across the region, as human population density increases, presence of large-bodied fishes declines, and fish communities become dominated by a few smaller-bodied species. Conclusions/Significance Complete disappearance of several large-bodied fishes indicates ecological and local extinctions have occurred in some densely populated areas. These findings fill a fundamentally important gap in our knowledge of the ecosystem effects of artisanal fisheries in developing nations, and provide support for multiple approaches to data collection where they are commonly unavailable. PMID:19421312

Management recommendations for the northern goshawk in the southwestern United States

Treesearch

Richard T. Reynolds; Russell T. Graham; M. Hildegard Reiser

1992-01-01

Present forest conditions ­ loss of a herbaceous and shrubby understory, reductions in the amount of older forests, and increased areas of dense tree regeneration ­ reflect the extent of human influence on these forests. These changes may also be affecting goshawk populations. Information on goshawk nesting habitat and foraging behavior, and the food and habitats of...

A competitive advantage by neonatally engrafted human glial progenitors yields mice whose brains are chimeric for human glia.

PubMed

Windrem, Martha S; Schanz, Steven J; Morrow, Carolyn; Munir, Jared; Chandler-Militello, Devin; Wang, Su; Goldman, Steven A

2014-11-26

Neonatally transplanted human glial progenitor cells (hGPCs) densely engraft and myelinate the hypomyelinated shiverer mouse. We found that, in hGPC-xenografted mice, the human donor cells continue to expand throughout the forebrain, systematically replacing the host murine glia. The differentiation of the donor cells is influenced by the host environment, such that more donor cells differentiated as oligodendrocytes in the hypomyelinated shiverer brain than in myelin wild-types, in which hGPCs were more likely to remain as progenitors. Yet in each recipient, both the number and relative proportion of mouse GPCs fell as a function of time, concomitant with the mitotic expansion and spread of donor hGPCs. By a year after neonatal xenograft, the forebrain GPC populations of implanted mice were largely, and often entirely, of human origin. Thus, neonatally implanted hGPCs outcompeted and ultimately replaced the host population of mouse GPCs, ultimately generating mice with a humanized glial progenitor population. These human glial chimeric mice should permit us to define the specific contributions of glia to a broad variety of neurological disorders, using human cells in vivo. Copyright © 2014 the authors 0270-6474/14/3416153-09$15.00/0.

DICCCOL: Dense Individualized and Common Connectivity-Based Cortical Landmarks

PubMed Central

Zhu, Dajiang; Guo, Lei; Jiang, Xi; Zhang, Tuo; Zhang, Degang; Chen, Hanbo; Deng, Fan; Faraco, Carlos; Jin, Changfeng; Wee, Chong-Yaw; Yuan, Yixuan; Lv, Peili; Yin, Yan; Hu, Xiaolei; Duan, Lian; Hu, Xintao; Han, Junwei; Wang, Lihong; Shen, Dinggang; Miller, L Stephen

2013-01-01

Is there a common structural and functional cortical architecture that can be quantitatively encoded and precisely reproduced across individuals and populations? This question is still largely unanswered due to the vast complexity, variability, and nonlinearity of the cerebral cortex. Here, we hypothesize that the common cortical architecture can be effectively represented by group-wise consistent structural fiber connections and take a novel data-driven approach to explore the cortical architecture. We report a dense and consistent map of 358 cortical landmarks, named Dense Individualized and Common Connectivity–based Cortical Landmarks (DICCCOLs). Each DICCCOL is defined by group-wise consistent white-matter fiber connection patterns derived from diffusion tensor imaging (DTI) data. Our results have shown that these 358 landmarks are remarkably reproducible over more than one hundred human brains and possess accurate intrinsically established structural and functional cross-subject correspondences validated by large-scale functional magnetic resonance imaging data. In particular, these 358 cortical landmarks can be accurately and efficiently predicted in a new single brain with DTI data. Thus, this set of 358 DICCCOL landmarks comprehensively encodes the common structural and functional cortical architectures, providing opportunities for many applications in brain science including mapping human brain connectomes, as demonstrated in this work. PMID:22490548

Roles of Spatial Scale and Rarity on the Relationship between Butterfly Species Richness and Human Density in South Africa

PubMed Central

Mecenero, Silvia; Altwegg, Res; Colville, Jonathan F.; Beale, Colin M.

2015-01-01

Wildlife and humans tend to prefer the same productive environments, yet high human densities often lead to reduced biodiversity. Species richness is often positively correlated with human population density at broad scales, but this correlation could also be caused by unequal sampling effort leading to higher species tallies in areas of dense human activity. We examined the relationships between butterfly species richness and human population density at five spatial resolutions ranging from 2' to 60' across South Africa. We used atlas-type data and spatial interpolation techniques aimed at reducing the effect of unequal spatial sampling. Our results confirm the general positive correlation between total species richness and human population density. Contrary to our expectations, the strength of this positive correlation did not weaken at finer spatial resolutions. The patterns observed using total species richness were driven mostly by common species. The richness of threatened and restricted range species was not correlated to human population density. None of the correlations we examined were particularly strong, with much unexplained variance remaining, suggesting that the overlap between butterflies and humans is not strong compared to other factors not accounted for in our analyses. Special consideration needs to be made regarding conservation goals and variables used when investigating the overlap between species and humans for biodiversity conservation. PMID:25915899

Roles of Spatial Scale and Rarity on the Relationship between Butterfly Species Richness and Human Density in South Africa.

PubMed

Mecenero, Silvia; Altwegg, Res; Colville, Jonathan F; Beale, Colin M

2015-01-01

Wildlife and humans tend to prefer the same productive environments, yet high human densities often lead to reduced biodiversity. Species richness is often positively correlated with human population density at broad scales, but this correlation could also be caused by unequal sampling effort leading to higher species tallies in areas of dense human activity. We examined the relationships between butterfly species richness and human population density at five spatial resolutions ranging from 2' to 60' across South Africa. We used atlas-type data and spatial interpolation techniques aimed at reducing the effect of unequal spatial sampling. Our results confirm the general positive correlation between total species richness and human population density. Contrary to our expectations, the strength of this positive correlation did not weaken at finer spatial resolutions. The patterns observed using total species richness were driven mostly by common species. The richness of threatened and restricted range species was not correlated to human population density. None of the correlations we examined were particularly strong, with much unexplained variance remaining, suggesting that the overlap between butterflies and humans is not strong compared to other factors not accounted for in our analyses. Special consideration needs to be made regarding conservation goals and variables used when investigating the overlap between species and humans for biodiversity conservation.

Endemic Dengue Associated with the Co-Circulation of Multiple Viral Lineages and Localized Density-Dependent Transmission

PubMed Central

Raghwani, Jayna; Rambaut, Andrew; Holmes, Edward C.; Hang, Vu Ty; Hien, Tran Tinh; Farrar, Jeremy; Wills, Bridget; Lennon, Niall J.; Birren, Bruce W.; Henn, Matthew R.; Simmons, Cameron P.

2011-01-01

Dengue is one of the most important infectious diseases of humans and has spread throughout much of the tropical and subtropical world. Despite this widespread dispersal, the determinants of dengue transmission in endemic populations are not well understood, although essential for virus control. To address this issue we performed a phylogeographic analysis of 751 complete genome sequences of dengue 1 virus (DENV-1) sampled from both rural (Dong Thap) and urban (Ho Chi Minh City) populations in southern Viet Nam during the period 2003–2008. We show that DENV-1 in Viet Nam exhibits strong spatial clustering, with likely importation from Cambodia on multiple occasions. Notably, multiple lineages of DENV-1 co-circulated in Ho Chi Minh City. That these lineages emerged at approximately the same time and dispersed over similar spatial regions suggests that they are of broadly equivalent fitness. We also observed an important relationship between the density of the human host population and the dispersion rate of dengue, such that DENV-1 tends to move from urban to rural populations, and that densely populated regions within Ho Chi Minh City act as major transmission foci. Despite these fluid dynamics, the dispersion rates of DENV-1 are relatively low, particularly in Ho Chi Minh City where the virus moves less than an average of 20 km/year. These low rates suggest a major role for mosquito-mediated dispersal, such that DENV-1 does not need to move great distances to infect a new host when there are abundant susceptibles, and imply that control measures should be directed toward the most densely populated urban environments. PMID:21655108

A multi-scale study of Orthoptera species richness and human population size controlling for sampling effort

NASA Astrophysics Data System (ADS)

Cantarello, Elena; Steck, Claude E.; Fontana, Paolo; Fontaneto, Diego; Marini, Lorenzo; Pautasso, Marco

2010-03-01

Recent large-scale studies have shown that biodiversity-rich regions also tend to be densely populated areas. The most obvious explanation is that biodiversity and human beings tend to match the distribution of energy availability, environmental stability and/or habitat heterogeneity. However, the species-people correlation can also be an artefact, as more populated regions could show more species because of a more thorough sampling. Few studies have tested this sampling bias hypothesis. Using a newly collated dataset, we studied whether Orthoptera species richness is related to human population size in Italy’s regions (average area 15,000 km2) and provinces (2,900 km2). As expected, the observed number of species increases significantly with increasing human population size for both grain sizes, although the proportion of variance explained is minimal at the provincial level. However, variations in observed Orthoptera species richness are primarily associated with the available number of records, which is in turn well correlated with human population size (at least at the regional level). Estimated Orthoptera species richness (Chao2 and Jackknife) also increases with human population size both for regions and provinces. Both for regions and provinces, this increase is not significant when controlling for variation in area and number of records. Our study confirms the hypothesis that broad-scale human population-biodiversity correlations can in some cases be artefactual. More systematic sampling of less studied taxa such as invertebrates is necessary to ascertain whether biogeographical patterns persist when sampling effort is kept constant or included in models.

Bioconvection as a Consequence of Bio-Stratification in Bacterial Populations

NASA Astrophysics Data System (ADS)

Shoup, Daniel; Strickland, Benjamin; Hoeger, Kentaro; Ursell, Tristan

The collective motion of bacterial populations in solution can generate convective currents that significantly alter fluid motion and material transport. Known as bioconvection, this process is highly influenced by stimuli such as nutrients and toxins that can attract or repel bacteria via chemotaxis. Despite its prevalence in natural environments, ranging from the ocean floor to fluid in the human gut, this dynamic process and the physical and biological factors that influence it remain largely unexplored. To close this gap, we measure and analyze spontaneous bioconvection arising from the collective movement of dense populations of bacteria, such as Escherichia coli and Bacillus subtilis. By combining microscopy and image analysis, we find that modulations of the fluid volume geometry, erasure of the air-liquid interface, chemical perturbations like nutrients or antibiotics all alter the development of these dense bacterial masses and in turn the bio-convective currents and corresponding transport phenomena they generate. Our work suggests biophysical principles of material and organismal transport that apply to a broad range of systems where organisms can sense gradients and move within their environments.

Population growth and consumption.

PubMed

Chalkley, K

1997-04-01

The relationship between population growth, resource consumption, and environmental degradation is complex. The rise in "greenhouse gases" that will cause climatic change is clearly due to human activity, and pollutants are often concentrated in densely populated areas. However, even an area with a negative population growth, such as Russia, can experience severe environmental degradation due to poor management. Consumption patterns have the most effect on ozone depletion, while population growth threatens biodiversity of and within species through the destruction of ecosystems. Migration joins population growth and social factors, such as land inequality, as major causes of deforestation, and global demand for water is expected to increase faster than the rate of population growth. Coastal development and over-fishing threaten to deplete the oceans, while soil quality is threatened by inappropriate land use. Estimates of the earth's carrying capacity range from less than 3 billion to more than 44 billion people, indicating how difficult it is to assess this figure. Development efforts throughout the world may lead to human gains that will ultimately be negated by environmental losses. These factors have led to growing support for environmentally sustainable development.

Estimating population sizes for elusive animals: the forest elephants of Kakum National Park, Ghana.

PubMed

Eggert, L S; Eggert, J A; Woodruff, D S

2003-06-01

African forest elephants are difficult to observe in the dense vegetation, and previous studies have relied upon indirect methods to estimate population sizes. Using multilocus genotyping of noninvasively collected samples, we performed a genetic survey of the forest elephant population at Kakum National Park, Ghana. We estimated population size, sex ratio and genetic variability from our data, then combined this information with field observations to divide the population into age groups. Our population size estimate was very close to that obtained using dung counts, the most commonly used indirect method of estimating the population sizes of forest elephant populations. As their habitat is fragmented by expanding human populations, management will be increasingly important to the persistence of forest elephant populations. The data that can be obtained from noninvasively collected samples will help managers plan for the conservation of this keystone species.

Linking Microbiota to Human Diseases: A Systems Biology Perspective.

PubMed

Wu, Hao; Tremaroli, Valentina; Bäckhed, Fredrik

2015-12-01

The human gut microbiota encompasses a densely populated ecosystem that provides essential functions for host development, immune maturation, and metabolism. Alterations to the gut microbiota have been observed in numerous diseases, including human metabolic diseases such as obesity, type 2 diabetes (T2D), and irritable bowel syndrome, and some animal experiments have suggested causality. However, few studies have validated causality in humans and the underlying mechanisms remain largely to be elucidated. We discuss how systems biology approaches combined with new experimental technologies may disentangle some of the mechanistic details in the complex interactions of diet, microbiota, and host metabolism and may provide testable hypotheses for advancing our current understanding of human-microbiota interaction. Copyright © 2015 Elsevier Ltd. All rights reserved.

Human drivers of ecological and evolutionary dynamics in emerging and disappearing infectious disease systems.

PubMed

Rogalski, Mary A; Gowler, Camden D; Shaw, Clara L; Hufbauer, Ruth A; Duffy, Meghan A

2017-01-19

Humans have contributed to the increased frequency and severity of emerging infectious diseases, which pose a significant threat to wild and domestic species, as well as human health. This review examines major pathways by which humans influence parasitism by altering (co)evolutionary interactions between hosts and parasites on ecological timescales. There is still much to learn about these interactions, but a few well-studied cases show that humans influence disease emergence every step of the way. Human actions significantly increase dispersal of host, parasite and vector species, enabling greater frequency of infection in naive host populations and host switches. Very dense host populations resulting from urbanization and agriculture can drive the evolution of more virulent parasites and, in some cases, more resistant host populations. Human activities that reduce host genetic diversity or impose abiotic stress can impair the ability of hosts to adapt to disease threats. Further, evolutionary responses of hosts and parasites can thwart disease management and biocontrol efforts. Finally, in rare cases, humans influence evolution by eradicating an infectious disease. If we hope to fully understand the factors driving disease emergence and potentially control these epidemics we must consider the widespread influence of humans on host and parasite evolutionary trajectories.This article is part of the themed issue 'Human influences on evolution, and the ecological and societal consequences'. © 2016 The Author(s).

Early animal farming and zoonotic disease dynamics: modelling brucellosis transmission in Neolithic goat populations.

PubMed

Fournié, Guillaume; Pfeiffer, Dirk U; Bendrey, Robin

2017-02-01

Zoonotic pathogens are frequently hypothesized as emerging with the origins of farming, but evidence of this is elusive in the archaeological records. To explore the potential impact of animal domestication on zoonotic disease dynamics and human infection risk, we developed a model simulating the transmission of Brucella melitensis within early domestic goat populations. The model was informed by archaeological data describing goat populations in Neolithic settlements in the Fertile Crescent, and used to assess the potential of these populations to sustain the circulation of Brucella . Results show that the pathogen could have been sustained even at low levels of transmission within these domestic goat populations. This resulted from the creation of dense populations and major changes in demographic characteristics. The selective harvesting of young male goats, likely aimed at improving the efficiency of food production, modified the age and sex structure of these populations, increasing the transmission potential of the pathogen within these populations. Probable interactions between Neolithic settlements would have further promoted pathogen maintenance. By fostering conditions suitable for allowing domestic goats to become reservoirs of Brucella melitensis , the early stages of agricultural development were likely to promote the exposure of humans to this pathogen.

Early animal farming and zoonotic disease dynamics: modelling brucellosis transmission in Neolithic goat populations

PubMed Central

Pfeiffer, Dirk U.; Bendrey, Robin

2017-01-01

Zoonotic pathogens are frequently hypothesized as emerging with the origins of farming, but evidence of this is elusive in the archaeological records. To explore the potential impact of animal domestication on zoonotic disease dynamics and human infection risk, we developed a model simulating the transmission of Brucella melitensis within early domestic goat populations. The model was informed by archaeological data describing goat populations in Neolithic settlements in the Fertile Crescent, and used to assess the potential of these populations to sustain the circulation of Brucella. Results show that the pathogen could have been sustained even at low levels of transmission within these domestic goat populations. This resulted from the creation of dense populations and major changes in demographic characteristics. The selective harvesting of young male goats, likely aimed at improving the efficiency of food production, modified the age and sex structure of these populations, increasing the transmission potential of the pathogen within these populations. Probable interactions between Neolithic settlements would have further promoted pathogen maintenance. By fostering conditions suitable for allowing domestic goats to become reservoirs of Brucella melitensis, the early stages of agricultural development were likely to promote the exposure of humans to this pathogen. PMID:28386446

Estimating average growth trajectories in shape-space using kernel smoothing.

PubMed

Hutton, Tim J; Buxton, Bernard F; Hammond, Peter; Potts, Henry W W

2003-06-01

In this paper, we show how a dense surface point distribution model of the human face can be computed and demonstrate the usefulness of the high-dimensional shape-space for expressing the shape changes associated with growth and aging. We show how average growth trajectories for the human face can be computed in the absence of longitudinal data by using kernel smoothing across a population. A training set of three-dimensional surface scans of 199 male and 201 female subjects of between 0 and 50 years of age is used to build the model.

Big Cats in Our Backyards: Persistence of Large Carnivores in a Human Dominated Landscape in India

PubMed Central

Athreya, Vidya; Odden, Morten; Linnell, John D. C.; Krishnaswamy, Jagdish; Karanth, Ullas

2013-01-01

Protected areas are extremely important for the long term viability of biodiversity in a densely populated country like India where land is a scarce resource. However, protected areas cover only 5% of the land area in India and in the case of large carnivores that range widely, human use landscapes will function as important habitats required for gene flow to occur between protected areas. In this study, we used photographic capture recapture analysis to assess the density of large carnivores in a human-dominated agricultural landscape with density >300 people/km2 in western Maharashtra, India. We found evidence of a wide suite of wild carnivores inhabiting a cropland landscape devoid of wilderness and wild herbivore prey. Furthermore, the large carnivores; leopard (Panthera pardus) and striped hyaena (Hyaena hyaena) occurred at relatively high density of 4.8±1.2 (sd) adults/100 km2 and 5.03±1.3 (sd) adults/100 km2 respectively. This situation has never been reported before where 10 large carnivores/100 km2 are sharing space with dense human populations in a completely modified landscape. Human attacks by leopards were rare despite a potentially volatile situation considering that the leopard has been involved in serious conflict, including human deaths in adjoining areas. The results of our work push the frontiers of our understanding of the adaptability of both, humans and wildlife to each other’s presence. The results also highlight the urgent need to shift from a PA centric to a landscape level conservation approach, where issues are more complex, and the potential for conflict is also very high. It also highlights the need for a serious rethink of conservation policy, law and practice where the current management focus is restricted to wildlife inside Protected Areas. PMID:23483933

Regional paleofire regimes affected by non-uniform climate, vegetation and human drivers

NASA Astrophysics Data System (ADS)

Blarquez, Olivier; Ali, Adam A.; Girardin, Martin P.; Grondin, Pierre; Fréchette, Bianca; Bergeron, Yves; Hély, Christelle

2015-09-01

Climate, vegetation and humans act on biomass burning at different spatial and temporal scales. In this study, we used a dense network of sedimentary charcoal records from eastern Canada to reconstruct regional biomass burning history over the last 7000 years at the scale of four potential vegetation types: open coniferous forest/tundra, boreal coniferous forest, boreal mixedwood forest and temperate forest. The biomass burning trajectories were compared with regional climate trends reconstructed from general circulation models, tree biomass reconstructed from pollen series, and human population densities. We found that non-uniform climate, vegetation and human drivers acted on regional biomass burning history. In the open coniferous forest/tundra and dense coniferous forest, the regional biomass burning was primarily shaped by gradual establishment of less climate-conducive burning conditions over 5000 years. In the mixed boreal forest an increasing relative proportion of flammable conifers in landscapes since 2000 BP contributed to maintaining biomass burning constant despite climatic conditions less favourable to fires. In the temperate forest, biomass burning was uncoupled with climatic conditions and the main driver was seemingly vegetation until European colonization, i.e. 300 BP. Tree biomass and thus fuel accumulation modulated fire activity, an indication that biomass burning is fuel-dependent and notably upon long-term co-dominance shifts between conifers and broadleaf trees.

Human migration is important in the international spread of exotic Salmonella serovars in animal and human populations.

PubMed

Iveson, J B; Bradshaw, S D; How, R A; Smith, D W

2014-11-01

The exposure of indigenous humans and native fauna in Australia and the Wallacea zoogeographical region of Indonesia to exotic Salmonella serovars commenced during the colonial period and has accelerated with urbanization and international travel. In this study, the distribution and prevalence of exotic Salmonella serovars are mapped to assess the extent to which introduced infections are invading native wildlife in areas of high natural biodiversity under threat from expanding human activity. The major exotic Salmonella serovars, Bovismorbificans, Derby, Javiana, Newport, Panama, Saintpaul and Typhimurium, isolated from wildlife on populated coastal islands in southern temperate areas of Western Australia, were mostly absent from reptiles and native mammals in less populated tropical areas of the state. They were also not recorded on the uninhabited Mitchell Plateau or islands of the Bonaparte Archipelago, adjacent to south-eastern Indonesia. Exotic serovars were, however, isolated in wildlife on 14/17 islands sampled in the Wallacea region of Indonesia and several islands off the west coast of Perth. Increases in international tourism, involving islands such as Bali, have resulted in the isolation of a high proportion of exotic serovar infections suggesting that densely populated island resorts in the Asian region are acting as staging posts for the interchange of Salmonella infections between tropical and temperate regions.

Indirect effects of human-induced environmental change on offspring production mediated by behavioural responses.

PubMed

Candolin, Ulrika; Nieminen, Anne; Nyman, Johanna

2014-01-01

Human-induced rapid environmental changes often cause behavioural alterations in animals. The consequences that these alterations in turn have for the viability of populations are, however, poorly known. We used a population of threespine sticklebacks Gasterosteus aculeatus in the Baltic Sea to investigate the consequences of behavioural responses to human-induced eutrophication for offspring production. The investigated population has been growing during the last decades, and one cause could be increased offspring production. We combined field-based surveys with laboratory-based experiments, and found that an enhanced growth of macroalgae relaxed agonistic interactions among males. This allowed more males to nest, improved hatching success, and increased the number of reproductive cycles that males completed. Thus, the behavioural responses were adaptive at the individual level and increased offspring production. However, a larger proportion of small males of low competitive ability reproduced in dense vegetation. As male size and dominance are heritable, this could influence the genetic composition of the offspring. Together with a higher number of offspring produced, this could influence natural selection and the rate of adaptation to the changing environment. Thus, behavioural responses to a rapid human-induced environmental change can influence offspring production, with potential consequences for population dynamics and evolutionary processes.

Genome-wide detection and characterization of positive selection in human populations.

PubMed

Sabeti, Pardis C; Varilly, Patrick; Fry, Ben; Lohmueller, Jason; Hostetter, Elizabeth; Cotsapas, Chris; Xie, Xiaohui; Byrne, Elizabeth H; McCarroll, Steven A; Gaudet, Rachelle; Schaffner, Stephen F; Lander, Eric S; Frazer, Kelly A; Ballinger, Dennis G; Cox, David R; Hinds, David A; Stuve, Laura L; Gibbs, Richard A; Belmont, John W; Boudreau, Andrew; Hardenbol, Paul; Leal, Suzanne M; Pasternak, Shiran; Wheeler, David A; Willis, Thomas D; Yu, Fuli; Yang, Huanming; Zeng, Changqing; Gao, Yang; Hu, Haoran; Hu, Weitao; Li, Chaohua; Lin, Wei; Liu, Siqi; Pan, Hao; Tang, Xiaoli; Wang, Jian; Wang, Wei; Yu, Jun; Zhang, Bo; Zhang, Qingrun; Zhao, Hongbin; Zhao, Hui; Zhou, Jun; Gabriel, Stacey B; Barry, Rachel; Blumenstiel, Brendan; Camargo, Amy; Defelice, Matthew; Faggart, Maura; Goyette, Mary; Gupta, Supriya; Moore, Jamie; Nguyen, Huy; Onofrio, Robert C; Parkin, Melissa; Roy, Jessica; Stahl, Erich; Winchester, Ellen; Ziaugra, Liuda; Altshuler, David; Shen, Yan; Yao, Zhijian; Huang, Wei; Chu, Xun; He, Yungang; Jin, Li; Liu, Yangfan; Shen, Yayun; Sun, Weiwei; Wang, Haifeng; Wang, Yi; Wang, Ying; Xiong, Xiaoyan; Xu, Liang; Waye, Mary M Y; Tsui, Stephen K W; Xue, Hong; Wong, J Tze-Fei; Galver, Luana M; Fan, Jian-Bing; Gunderson, Kevin; Murray, Sarah S; Oliphant, Arnold R; Chee, Mark S; Montpetit, Alexandre; Chagnon, Fanny; Ferretti, Vincent; Leboeuf, Martin; Olivier, Jean-François; Phillips, Michael S; Roumy, Stéphanie; Sallée, Clémentine; Verner, Andrei; Hudson, Thomas J; Kwok, Pui-Yan; Cai, Dongmei; Koboldt, Daniel C; Miller, Raymond D; Pawlikowska, Ludmila; Taillon-Miller, Patricia; Xiao, Ming; Tsui, Lap-Chee; Mak, William; Song, You Qiang; Tam, Paul K H; Nakamura, Yusuke; Kawaguchi, Takahisa; Kitamoto, Takuya; Morizono, Takashi; Nagashima, Atsushi; Ohnishi, Yozo; Sekine, Akihiro; Tanaka, Toshihiro; Tsunoda, Tatsuhiko; Deloukas, Panos; Bird, Christine P; Delgado, Marcos; Dermitzakis, Emmanouil T; Gwilliam, Rhian; Hunt, Sarah; Morrison, Jonathan; Powell, Don; Stranger, Barbara E; Whittaker, Pamela; Bentley, David R; Daly, Mark J; de Bakker, Paul I W; Barrett, Jeff; Chretien, Yves R; Maller, Julian; McCarroll, Steve; Patterson, Nick; Pe'er, Itsik; Price, Alkes; Purcell, Shaun; Richter, Daniel J; Sabeti, Pardis; Saxena, Richa; Schaffner, Stephen F; Sham, Pak C; Varilly, Patrick; Altshuler, David; Stein, Lincoln D; Krishnan, Lalitha; Smith, Albert Vernon; Tello-Ruiz, Marcela K; Thorisson, Gudmundur A; Chakravarti, Aravinda; Chen, Peter E; Cutler, David J; Kashuk, Carl S; Lin, Shin; Abecasis, Gonçalo R; Guan, Weihua; Li, Yun; Munro, Heather M; Qin, Zhaohui Steve; Thomas, Daryl J; McVean, Gilean; Auton, Adam; Bottolo, Leonardo; Cardin, Niall; Eyheramendy, Susana; Freeman, Colin; Marchini, Jonathan; Myers, Simon; Spencer, Chris; Stephens, Matthew; Donnelly, Peter; Cardon, Lon R; Clarke, Geraldine; Evans, David M; Morris, Andrew P; Weir, Bruce S; Tsunoda, Tatsuhiko; Johnson, Todd A; Mullikin, James C; Sherry, Stephen T; Feolo, Michael; Skol, Andrew; Zhang, Houcan; Zeng, Changqing; Zhao, Hui; Matsuda, Ichiro; Fukushima, Yoshimitsu; Macer, Darryl R; Suda, Eiko; Rotimi, Charles N; Adebamowo, Clement A; Ajayi, Ike; Aniagwu, Toyin; Marshall, Patricia A; Nkwodimmah, Chibuzor; Royal, Charmaine D M; Leppert, Mark F; Dixon, Missy; Peiffer, Andy; Qiu, Renzong; Kent, Alastair; Kato, Kazuto; Niikawa, Norio; Adewole, Isaac F; Knoppers, Bartha M; Foster, Morris W; Clayton, Ellen Wright; Watkin, Jessica; Gibbs, Richard A; Belmont, John W; Muzny, Donna; Nazareth, Lynne; Sodergren, Erica; Weinstock, George M; Wheeler, David A; Yakub, Imtaz; Gabriel, Stacey B; Onofrio, Robert C; Richter, Daniel J; Ziaugra, Liuda; Birren, Bruce W; Daly, Mark J; Altshuler, David; Wilson, Richard K; Fulton, Lucinda L; Rogers, Jane; Burton, John; Carter, Nigel P; Clee, Christopher M; Griffiths, Mark; Jones, Matthew C; McLay, Kirsten; Plumb, Robert W; Ross, Mark T; Sims, Sarah K; Willey, David L; Chen, Zhu; Han, Hua; Kang, Le; Godbout, Martin; Wallenburg, John C; L'Archevêque, Paul; Bellemare, Guy; Saeki, Koji; Wang, Hongguang; An, Daochang; Fu, Hongbo; Li, Qing; Wang, Zhen; Wang, Renwu; Holden, Arthur L; Brooks, Lisa D; McEwen, Jean E; Guyer, Mark S; Wang, Vivian Ota; Peterson, Jane L; Shi, Michael; Spiegel, Jack; Sung, Lawrence M; Zacharia, Lynn F; Collins, Francis S; Kennedy, Karen; Jamieson, Ruth; Stewart, John

2007-10-18

With the advent of dense maps of human genetic variation, it is now possible to detect positive natural selection across the human genome. Here we report an analysis of over 3 million polymorphisms from the International HapMap Project Phase 2 (HapMap2). We used 'long-range haplotype' methods, which were developed to identify alleles segregating in a population that have undergone recent selection, and we also developed new methods that are based on cross-population comparisons to discover alleles that have swept to near-fixation within a population. The analysis reveals more than 300 strong candidate regions. Focusing on the strongest 22 regions, we develop a heuristic for scrutinizing these regions to identify candidate targets of selection. In a complementary analysis, we identify 26 non-synonymous, coding, single nucleotide polymorphisms showing regional evidence of positive selection. Examination of these candidates highlights three cases in which two genes in a common biological process have apparently undergone positive selection in the same population:LARGE and DMD, both related to infection by the Lassa virus, in West Africa;SLC24A5 and SLC45A2, both involved in skin pigmentation, in Europe; and EDAR and EDA2R, both involved in development of hair follicles, in Asia.

A global reference for human genetic variation

PubMed Central

2016-01-01

The 1000 Genomes Project set out to provide a comprehensive description of common human genetic variation by applying whole-genome sequencing to a diverse set of individuals from multiple populations. Here we report completion of the project, having reconstructed the genomes of 2,504 individuals from 26 populations using a combination of low-coverage whole-genome sequencing, deep exome sequencing, and dense microarray genotyping. We characterized a broad spectrum of genetic variation, in total over 88 million variants (84.7 million single nucleotide polymorphisms (SNPs), 3.6 million short insertions/deletions (indels), and 60,000 structural variants), all phased onto high-quality haplotypes. This resource includes >99% of SNP variants with a frequency of >1% for a variety of ancestries. We describe the distribution of genetic variation across the global sample, and discuss the implications for common disease studies. PMID:26432245

Status and management of moose in the northeastern United States

USGS Publications Warehouse

Wattles, David W.; DeStefano, Stephen

2011-01-01

Moose (Alces alces) populations have recolonized much of their historic range in the northeastern United States in the past 30 years, with their southern range edge extending to southern New England and northern New York. This southerly expansion occurred when certain other populations in the United States were in decline along the southern range edge, with climate change often cited as a probable cause. The areas that moose have recently occupied in the northeastern United States are some of the most densely human populated in moose range, which has raised concern about human safety and moose-vehicle collisions (MVC). We conducted a literature search about moose in the northeastern United States, and distributed a questionnaire and conducted phone interviews with regional biologists responsible for moose management to determine the status of moose, management activity, and research deficiencies and needs. Moose numbers appear stable throughout much of the region, with slow population growth in northern New York. Management activity ranges from regulated harvest of moose in Maine, New Hampshire, and Vermont, to no active management in southern New England and New York. The combined annual harvest in Maine, New Hampshire, and Vermont is >3,000. MVCs are a widespread regional concern with >1,000 occurring annually involving several human fatalities. Research should address impacts of parasitism by winter tick (Dermacentor albipictus) and brain-worm (Parelaphostrongylus tenuis) on productivity and mortality of moose, influence of climate change on population dynamics and range, and conflicts in areas with high human population density.

Effects of directional migration on prisoner's dilemma game in a square domain

NASA Astrophysics Data System (ADS)

Cheng, Hongyan; Dai, Qionglin; Li, Haihong; Qian, Xiaolan; Zhang, Mei; Yang, Junzhong

2013-04-01

We introduce a new migration rule, the directional migration, into evolutionary prisoner's dilemma games defined in a square domain with periodic boundary conditions. We find that cooperation can be enhanced to a much higher level than the case in the absence of migration. Additionally, the presence of the directional migration has profound impact on the population structure: the directional migration drives individuals to form a number of dense clusters which resembles social cohesion. The evolutionary game theory incorporating the directional migration can reproduce some real characteristics of populations in human society and may shed light on the problem of social cohesion.

Metabolic heat production by human and animal populations in cities.

PubMed

Stewart, Iain D; Kennedy, Chris A

2017-07-01

Anthropogenic heating from building energy use, vehicle fuel consumption, and human metabolism is a key term in the urban energy budget equation. Heating from human metabolism, however, is often excluded from urban energy budgets because it is widely observed to be negligible. Few reports for low-latitude cities are available to support this observation, and no reports exist on the contribution of domestic animals to urban heat budgets. To provide a more comprehensive view of metabolic heating in cities, we quantified all terms of the anthropogenic heat budget at metropolitan scale for the world's 26 largest cities, using a top-down statistical approach. Results show that metabolic heat release from human populations in mid-latitude cities (e.g. London, Tokyo, New York) accounts for 4-8% of annual anthropogenic heating, compared to 10-45% in high-density tropical cities (e.g. Cairo, Dhaka, Kolkata). Heat release from animal populations amounts to <1% of anthropogenic heating in all cities. Heat flux density from human and animal metabolism combined is highest in Mumbai-the world's most densely populated megacity-at 6.5 W m -2 , surpassing heat production by electricity use in buildings (5.8 W m -2 ) and fuel combustion in vehicles (3.9 W m -2 ). These findings, along with recent output from global climate models, suggest that in the world's largest and most crowded cities, heat emissions from human metabolism alone can force measurable change in mean annual temperature at regional scale.

Metabolic heat production by human and animal populations in cities

NASA Astrophysics Data System (ADS)

Stewart, Iain D.; Kennedy, Chris A.

2017-07-01

Anthropogenic heating from building energy use, vehicle fuel consumption, and human metabolism is a key term in the urban energy budget equation. Heating from human metabolism, however, is often excluded from urban energy budgets because it is widely observed to be negligible. Few reports for low-latitude cities are available to support this observation, and no reports exist on the contribution of domestic animals to urban heat budgets. To provide a more comprehensive view of metabolic heating in cities, we quantified all terms of the anthropogenic heat budget at metropolitan scale for the world's 26 largest cities, using a top-down statistical approach. Results show that metabolic heat release from human populations in mid-latitude cities (e.g. London, Tokyo, New York) accounts for 4-8% of annual anthropogenic heating, compared to 10-45% in high-density tropical cities (e.g. Cairo, Dhaka, Kolkata). Heat release from animal populations amounts to <1% of anthropogenic heating in all cities. Heat flux density from human and animal metabolism combined is highest in Mumbai—the world's most densely populated megacity—at 6.5 W m-2, surpassing heat production by electricity use in buildings (5.8 W m-2) and fuel combustion in vehicles (3.9 W m-2). These findings, along with recent output from global climate models, suggest that in the world's largest and most crowded cities, heat emissions from human metabolism alone can force measurable change in mean annual temperature at regional scale.

Epidemiology of Viliuisk encephalomyelitis in Eastern Siberia.

PubMed

Lee, Hee Suk; Zhdanova, Svetlana N; Vladimirtsev, Vsevolod A; Platonov, Fyodor A; Osakovskiy, Vladimir L; Subbotina, Ekaterina L; Broytman, Oleg; Danilova, Al'bina P; Nikitina, Raisa S; Chepurnov, Alexander A; Krivoshapkin, Vadim G; Gajdusek, D Carleton; Savilov, Yevgeniy D; Garruto, Ralph M; Goldfarb, Lev G

2010-01-01

Viliuisk encephalomyelitis is a disorder that starts, in most cases, as an acute meningoencephalitis. Survivors of the acute phase develop a slowly progressing neurologic syndrome characterized by dementia, dysarthria, and spasticity. An epidemic of this disease has been spreading throughout the Yakut Republic of the Russian Federation. Although clinical, neuropathologic, and epidemiologic data suggest infectious etiology, multiple attempts at pathogen isolation have been unsuccessful. Detailed clinical, pathologic, laboratory, and epidemiologic studies have identified 414 patients with definite Viliuisk encephalomyelitis in 15 of 33 administrative regions of the Yakut Republic between 1940 and 1999. All data are documented in a Registry. The average annual Viliuisk encephalomyelitis incidence rate at the height of the epidemic reached 8.8 per 100,000 population and affected predominantly young adults. The initial outbreak occurred in a remote isolated area of the middle reaches of Viliui River; the disease spread to adjacent areas and further in the direction of more densely populated regions. The results suggest that intensified human migration from endemic villages led to the emergence of this disease in new communities. Recent social and demographic changes have presumably contributed to a subsequent decline in disease incidence. Based on the largest known set of diagnostically verified Viliuisk encephalomyelitis cases, we demonstrate how a previously little-known disease that was endemic in a small indigenous population subsequently reached densely populated areas and produced an epidemic involving hundreds of persons.

Large-scale absence of sharks on reefs in the greater-Caribbean: a footprint of human pressures.

PubMed

Ward-Paige, Christine A; Mora, Camilo; Lotze, Heike K; Pattengill-Semmens, Christy; McClenachan, Loren; Arias-Castro, Ery; Myers, Ransom A

2010-08-05

In recent decades, large pelagic and coastal shark populations have declined dramatically with increased fishing; however, the status of sharks in other systems such as coral reefs remains largely unassessed despite a long history of exploitation. Here we explore the contemporary distribution and sighting frequency of sharks on reefs in the greater-Caribbean and assess the possible role of human pressures on observed patterns. We analyzed 76,340 underwater surveys carried out by trained volunteer divers between 1993 and 2008. Surveys were grouped within one km2 cells, which allowed us to determine the contemporary geographical distribution and sighting frequency of sharks. Sighting frequency was calculated as the ratio of surveys with sharks to the total number of surveys in each cell. We compared sighting frequency to the number of people in the cell vicinity and used population viability analyses to assess the effects of exploitation on population trends. Sharks, with the exception of nurse sharks occurred mainly in areas with very low human population or strong fishing regulations and marine conservation. Population viability analysis suggests that exploitation alone could explain the large-scale absence; however, this pattern is likely to be exacerbated by additional anthropogenic stressors, such as pollution and habitat degradation, that also correlate with human population. Human pressures in coastal zones have lead to the broad-scale absence of sharks on reefs in the greater-Caribbean. Preventing further loss of sharks requires urgent management measures to curb fishing mortality and to mitigate other anthropogenic stressors to protect sites where sharks still exist. The fact that sharks still occur in some densely populated areas where strong fishing regulations are in place indicates the possibility of success and encourages the implementation of conservation measures.

Disentangling the relative effects of bushmeat availability on human nutrition in central Africa.

PubMed

Fa, John E; Olivero, Jesús; Real, Raimundo; Farfán, Miguel A; Márquez, Ana L; Vargas, J Mario; Ziegler, Stefan; Wegmann, Martin; Brown, David; Margetts, Barrie; Nasi, Robert

2015-02-02

We studied links between human malnutrition and wild meat availability within the Rainforest Biotic Zone in central Africa. We distinguished two distinct hunted mammalian diversity distributions, one in the rainforest areas (Deep Rainforest Diversity, DRD) containing taxa of lower hunting sustainability, the other in the northern rainforest-savanna mosaic, with species of greater hunting potential (Marginal Rainforest Diversity, MRD). Wild meat availability, assessed by standing crop mammalian biomass, was greater in MRD than in DRD areas. Predicted bushmeat extraction was also higher in MRD areas. Despite this, stunting of children, a measure of human malnutrition, was greater in MRD areas. Structural equation modeling identified that, in MRD areas, mammal diversity fell away from urban areas, but proximity to these positively influenced higher stunting incidence. In DRD areas, remoteness and distance from dense human settlements and infrastructures explained lower stunting levels. Moreover, stunting was higher away from protected areas. Our results suggest that in MRD areas, forest wildlife rational use for better human nutrition is possible. By contrast, the relatively low human populations in DRD areas currently offer abundant opportunities for the continued protection of more vulnerable mammals and allow dietary needs of local populations to be met.

Disentangling the relative effects of bushmeat availability on human nutrition in central Africa

NASA Astrophysics Data System (ADS)

Fa, John E.; Olivero, Jesús; Real, Raimundo; Farfán, Miguel A.; Márquez, Ana L.; Vargas, J. Mario; Ziegler, Stefan; Wegmann, Martin; Brown, David; Margetts, Barrie; Nasi, Robert

2015-02-01

We studied links between human malnutrition and wild meat availability within the Rainforest Biotic Zone in central Africa. We distinguished two distinct hunted mammalian diversity distributions, one in the rainforest areas (Deep Rainforest Diversity, DRD) containing taxa of lower hunting sustainability, the other in the northern rainforest-savanna mosaic, with species of greater hunting potential (Marginal Rainforest Diversity, MRD). Wild meat availability, assessed by standing crop mammalian biomass, was greater in MRD than in DRD areas. Predicted bushmeat extraction was also higher in MRD areas. Despite this, stunting of children, a measure of human malnutrition, was greater in MRD areas. Structural equation modeling identified that, in MRD areas, mammal diversity fell away from urban areas, but proximity to these positively influenced higher stunting incidence. In DRD areas, remoteness and distance from dense human settlements and infrastructures explained lower stunting levels. Moreover, stunting was higher away from protected areas. Our results suggest that in MRD areas, forest wildlife rational use for better human nutrition is possible. By contrast, the relatively low human populations in DRD areas currently offer abundant opportunities for the continued protection of more vulnerable mammals and allow dietary needs of local populations to be met.

Evaluating mortality rates with a novel integrated framework for nonmonogamous species.

PubMed

Tenan, Simone; Iemma, Aaron; Bragalanti, Natalia; Pedrini, Paolo; De Barba, Marta; Randi, Ettore; Groff, Claudio; Genovart, Meritxell

2016-12-01

The conservation of wildlife requires management based on quantitative evidence, and especially for large carnivores, unraveling cause-specific mortalities and understanding their impact on population dynamics is crucial. Acquiring this knowledge is challenging because it is difficult to obtain robust long-term data sets on endangered populations and, usually, data are collected through diverse sampling strategies. Integrated population models (IPMs) offer a way to integrate data generated through different processes. However, IPMs are female-based models that cannot account for mate availability, and this feature limits their applicability to monogamous species only. We extended classical IPMs to a two-sex framework that allows investigation of population dynamics and quantification of cause-specific mortality rates in nonmonogamous species. We illustrated our approach by simultaneously modeling different types of data from a reintroduced, unhunted brown bear (Ursus arctos) population living in an area with a dense human population. In a population mainly driven by adult survival, we estimated that on average 11% of cubs and 61% of adults died from human-related causes. Although the population is currently not at risk, adult survival and thus population dynamics are driven by anthropogenic mortality. Given the recent increase of human-bear conflicts in the area, removal of individuals for management purposes and through poaching may increase, reversing the positive population growth rate. Our approach can be generalized to other species affected by cause-specific mortality and will be useful to inform conservation decisions for other nonmonogamous species, such as most large carnivores, for which data are scarce and diverse and thus data integration is highly desirable. © 2016 Society for Conservation Biology.

Regional paleofire regimes affected by non-uniform climate, vegetation and human drivers

PubMed Central

Blarquez, Olivier; Ali, Adam A.; Girardin, Martin P.; Grondin, Pierre; Fréchette, Bianca; Bergeron, Yves; Hély, Christelle

2015-01-01

Climate, vegetation and humans act on biomass burning at different spatial and temporal scales. In this study, we used a dense network of sedimentary charcoal records from eastern Canada to reconstruct regional biomass burning history over the last 7000 years at the scale of four potential vegetation types: open coniferous forest/tundra, boreal coniferous forest, boreal mixedwood forest and temperate forest. The biomass burning trajectories were compared with regional climate trends reconstructed from general circulation models, tree biomass reconstructed from pollen series, and human population densities. We found that non-uniform climate, vegetation and human drivers acted on regional biomass burning history. In the open coniferous forest/tundra and dense coniferous forest, the regional biomass burning was primarily shaped by gradual establishment of less climate-conducive burning conditions over 5000 years. In the mixed boreal forest an increasing relative proportion of flammable conifers in landscapes since 2000 BP contributed to maintaining biomass burning constant despite climatic conditions less favourable to fires. In the temperate forest, biomass burning was uncoupled with climatic conditions and the main driver was seemingly vegetation until European colonization, i.e. 300 BP. Tree biomass and thus fuel accumulation modulated fire activity, an indication that biomass burning is fuel-dependent and notably upon long-term co-dominance shifts between conifers and broadleaf trees. PMID:26330162

The crowded life is a slow life: Population density and life history strategy.

PubMed

Sng, Oliver; Neuberg, Steven L; Varnum, Michael E W; Kenrick, Douglas T

2017-05-01

The world population has doubled over the last half century. Yet, research on the psychological effects of human population density, once a popular topic, has decreased over the past few decades. Applying a fresh perspective to an old topic, we draw upon life history theory to examine the effects of population density. Across nations and across the U.S. states (Studies 1 and 2), we find that dense populations exhibit behaviors corresponding to a slower life history strategy, including greater future-orientation, greater investment in education, more long-term mating orientation, later marriage age, lower fertility, and greater parental investment. In Studies 3 and 4, experimentally manipulating perceptions of high density led individuals to become more future-oriented. Finally, in Studies 5 and 6, experimentally manipulating perceptions of high density seemed to lead to life-stage-specific slower strategies, with college students preferring to invest in fewer rather than more relationship partners, and an older MTurk sample preferring to invest in fewer rather than more children. This research sheds new insight on the effects of density and its implications for human cultural variation and society at large. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

Population density, water supply, and the risk of dengue fever in Vietnam: cohort study and spatial analysis.

PubMed

Schmidt, Wolf-Peter; Suzuki, Motoi; Thiem, Vu Dinh; White, Richard G; Tsuzuki, Ataru; Yoshida, Lay-Myint; Yanai, Hideki; Haque, Ubydul; Tho, Le Huu; Anh, Dang Duc; Ariyoshi, Koya

2011-08-01

Aedes aegypti, the major vector of dengue viruses, often breeds in water storage containers used by households without tap water supply, and occurs in high numbers even in dense urban areas. We analysed the interaction between human population density and lack of tap water as a cause of dengue fever outbreaks with the aim of identifying geographic areas at highest risk. We conducted an individual-level cohort study in a population of 75,000 geo-referenced households in Vietnam over the course of two epidemics, on the basis of dengue hospital admissions (n = 3,013). We applied space-time scan statistics and mathematical models to confirm the findings. We identified a surprisingly narrow range of critical human population densities between around 3,000 to 7,000 people/km² prone to dengue outbreaks. In the study area, this population density was typical of villages and some peri-urban areas. Scan statistics showed that areas with a high population density or adequate water supply did not experience severe outbreaks. The risk of dengue was higher in rural than in urban areas, largely explained by lack of piped water supply, and in human population densities more often falling within the critical range. Mathematical modeling suggests that simple assumptions regarding area-level vector/host ratios may explain the occurrence of outbreaks. Rural areas may contribute at least as much to the dissemination of dengue fever as cities. Improving water supply and vector control in areas with a human population density critical for dengue transmission could increase the efficiency of control efforts. Please see later in the article for the Editors' Summary.

Population Density, Water Supply, and the Risk of Dengue Fever in Vietnam: Cohort Study and Spatial Analysis

PubMed Central

Schmidt, Wolf-Peter; Suzuki, Motoi; Dinh Thiem, Vu; White, Richard G.; Tsuzuki, Ataru; Yoshida, Lay-Myint; Yanai, Hideki; Haque, Ubydul; Huu Tho, Le; Anh, Dang Duc; Ariyoshi, Koya

2011-01-01

Background Aedes aegypti, the major vector of dengue viruses, often breeds in water storage containers used by households without tap water supply, and occurs in high numbers even in dense urban areas. We analysed the interaction between human population density and lack of tap water as a cause of dengue fever outbreaks with the aim of identifying geographic areas at highest risk. Methods and Findings We conducted an individual-level cohort study in a population of 75,000 geo-referenced households in Vietnam over the course of two epidemics, on the basis of dengue hospital admissions (n = 3,013). We applied space-time scan statistics and mathematical models to confirm the findings. We identified a surprisingly narrow range of critical human population densities between around 3,000 to 7,000 people/km2 prone to dengue outbreaks. In the study area, this population density was typical of villages and some peri-urban areas. Scan statistics showed that areas with a high population density or adequate water supply did not experience severe outbreaks. The risk of dengue was higher in rural than in urban areas, largely explained by lack of piped water supply, and in human population densities more often falling within the critical range. Mathematical modeling suggests that simple assumptions regarding area-level vector/host ratios may explain the occurrence of outbreaks. Conclusions Rural areas may contribute at least as much to the dissemination of dengue fever as cities. Improving water supply and vector control in areas with a human population density critical for dengue transmission could increase the efficiency of control efforts. Please see later in the article for the Editors' Summary PMID:21918642

Heavy metal contamination of coastal lagoon sediments: Fongafale Islet, Funafuti Atoll, Tuvalu.

PubMed

Fujita, Masafumi; Ide, Yoichi; Sato, Daisaku; Kench, Paul S; Kuwahara, Yuji; Yokoki, Hiromune; Kayanne, Hajime

2014-01-01

To evaluate contamination of coastal sediments along Fongafale Islet, Central Pacific, a field survey was conducted in densely populated, sparsely populated, open dumping and undisturbed natural areas. Current measurements in shallow water of the lagoon indicated that contaminants from the densely populated area would only be transported for a small proportion of a tidal cycle. Acid-volatile sulfides were detected in both the intertidal beach and nearshore zones of the densely populated area, whereas these were no detection in the other areas. This observation lends support to argument that the coastal pollution mechanism that during ebb tide, domestic wastewater leaking from poorly constructed sanitary facilities seeps into the coast. The total concentrations of Cr, Mn, Ni, Cu, Zn, Cd and Pb were relatively high in all of the areas except the undisturbed natural area. The indices of contamination factor, pollution load index and geoaccumulation index were indicative of heavy metal pollution in the three areas. The densely populated area has the most significant contamination; domestic wastewater led to significant contamination of coastal sediments with Cr, Zn, Cu, Pb and Cd. The open dumping area is noteworthy with respect to Mn and Ni, which can be derived from disposed batteries. Crown Copyright © 2013. Published by Elsevier Ltd. All rights reserved.

Rainfall-triggered landslides, anthropogenic hazards, and mitigation strategies

USGS Publications Warehouse

Larsen, M.C.

2008-01-01

Rainfall-triggered landslides are part of a natural process of hillslope erosion that can result in catastrophic loss of life and extensive property damage in mountainous, densely populated areas. As global population expansion on or near steep hillslopes continues, the human and economic costs associated with landslides will increase. Landslide hazard mitigation strategies generally involve hazard assessment mapping, warning systems, control structures, and regional landslide planning and policy development. To be sustainable, hazard mitigation requires that management of natural resources is closely connected to local economic and social interests. A successful strategy is dependent on a combination of multi-disciplinary scientific and engineering approaches, and the political will to take action at the local community to national scale.

San Francisco 's Golden Gate: A bridge between historically distinct coyote (Canis latrans) populations?

USGS Publications Warehouse

Sacks, Benjamin N.; Ernest, Holly B.; Boydston, Erin E.

2006-01-01

Although coyotes (Canis latrans) are wellknown for their adaptability to human-modified landscapes (Riley et al. 2003), as with any medium to large-sized carnivore, they typically avoid highly urbanized areas (Crooks 2002), preferring instead to use habitat fragments linked by vegetated corridors (Tigas et al. 2002). However, recent observations of coyotes in San Francisco indicate their willingness to traverse even the most densely urbanized terrain (Rubenstein 2003). Herein we use DNA to show, in an extreme example, that an adult male coyote caught in the northern tip of the San Francisco peninsula traversed the 2-km Golden Gate Bridge, potentially linking historically distinct coyote populations.

Comprehensive transcriptional map of primate brain development

PubMed Central

Bakken, Trygve E.; Miller, Jeremy A.; Ding, Song-Lin; Sunkin, Susan M.; Smith, Kimberly A.; Ng, Lydia; Szafer, Aaron; Dalley, Rachel A.; Royall, Joshua J.; Lemon, Tracy; Shapouri, Sheila; Aiona, Kaylynn; Arnold, James; Bennett, Jeffrey L.; Bertagnolli, Darren; Bickley, Kristopher; Boe, Andrew; Brouner, Krissy; Butler, Stephanie; Byrnes, Emi; Caldejon, Shiella; Carey, Anita; Cate, Shelby; Chapin, Mike; Chen, Jefferey; Dee, Nick; Desta, Tsega; Dolbeare, Tim A.; Dotson, Nadia; Ebbert, Amanda; Fulfs, Erich; Gee, Garrett; Gilbert, Terri L.; Goldy, Jeff; Gourley, Lindsey; Gregor, Ben; Gu, Guangyu; Hall, Jon; Haradon, Zeb; Haynor, David R.; Hejazinia, Nika; Hoerder-Suabedissen, Anna; Howard, Robert; Jochim, Jay; Kinnunen, Marty; Kriedberg, Ali; Kuan, Chihchau L.; Lau, Christopher; Lee, Chang-Kyu; Lee, Felix; Luong, Lon; Mastan, Naveed; May, Ryan; Melchor, Jose; Mosqueda, Nerick; Mott, Erika; Ngo, Kiet; Nyhus, Julie; Oldre, Aaron; Olson, Eric; Parente, Jody; Parker, Patrick D.; Parry, Sheana; Pendergraft, Julie; Potekhina, Lydia; Reding, Melissa; Riley, Zackery L.; Roberts, Tyson; Rogers, Brandon; Roll, Kate; Rosen, David; Sandman, David; Sarreal, Melaine; Shapovalova, Nadiya; Shi, Shu; Sjoquist, Nathan; Sodt, Andy J.; Townsend, Robbie; Velasquez, Lissette; Wagley, Udi; Wakeman, Wayne B.; White, Cassandra; Bennett, Crissa; Wu, Jennifer; Young, Rob; Youngstrom, Brian L.; Wohnoutka, Paul; Gibbs, Richard A.; Rogers, Jeffrey; Hohmann, John G.; Hawrylycz, Michael J.; Hevner, Robert F.; Molnár, Zoltán; Phillips, John W.; Dang, Chinh; Jones, Allan R.; Amaral, David G.; Bernard, Amy; Lein, Ed S.

2017-01-01

The transcriptional underpinnings of brain development remain poorly understood, particularly in humans and closely related non-human primates. We describe a high resolution transcriptional atlas of rhesus monkey brain development that combines dense temporal sampling of prenatal and postnatal periods with fine anatomical parcellation of cortical and subcortical regions associated with human neuropsychiatric disease. Gene expression changes more rapidly before birth, both in progenitor cells and maturing neurons, and cortical layers and areas acquire adult-like molecular profiles surprisingly late postnatally. Disparate cell populations exhibit distinct developmental timing but also unexpected synchrony of processes underlying neural circuit construction including cell projection and adhesion. Candidate risk genes for neurodevelopmental disorders including primary microcephaly, autism spectrum disorder, intellectual disability, and schizophrenia show disease-specific spatiotemporal enrichment within developing neocortex. Human developmental expression trajectories are more similar to monkey than rodent, and approximately 9% of genes show human-specific regulation with evidence for prolonged maturation or neoteny. PMID:27409810

Genome-Wide Landscapes of Human Local Adaptation in Asia

PubMed Central

Lu, Dongsheng; Xu, Shuhua

2013-01-01

Genetic studies of human local adaptation have been facilitated greatly by recent advances in high-throughput genotyping and sequencing technologies. However, few studies have investigated local adaptation in Asian populations on a genome-wide scale and with a high geographic resolution. In this study, taking advantage of the dense population coverage in Southeast Asia, which is the part of the world least studied in term of natural selection, we depicted genome-wide landscapes of local adaptations in 63 Asian populations representing the majority of linguistic and ethnic groups in Asia. Using genome-wide data analysis, we discovered many genes showing signs of local adaptation or natural selection. Notable examples, such as FOXQ1, MAST2, and CDH4, were found to play a role in hair follicle development and human cancer, signal transduction, and tumor repression, respectively. These showed strong indications of natural selection in Philippine Negritos, a group of aboriginal hunter-gatherers living in the Philippines. MTTP, which has associations with metabolic syndrome, body mass index, and insulin regulation, showed a strong signature of selection in Southeast Asians, including Indonesians. Functional annotation analysis revealed that genes and genetic variants underlying natural selections were generally enriched in the functional category of alternative splicing. Specifically, many genes showing significant difference with respect to allele frequency between northern and southern Asian populations were found to be associated with human height and growth and various immune pathways. In summary, this study contributes to the overall understanding of human local adaptation in Asia and has identified both known and novel signatures of natural selection in the human genome. PMID:23349834

Climate change and health: Why should India be concerned?

PubMed

Majra, J P; Gur, A

2009-04-01

Overwhelming evidence shows that climate change presents growing threats to public health security - from extreme weather-related disasters to wider spread of such vector-borne diseases as malaria and dengue. The impacts of climate on human health will not be evenly distributed around the world. The Third Assessment Report (Intergovernmental Panel on Climate Change-2001) concluded that vulnerability to climate change is a function of exposure, sensitivity, and adaptive capacity. Developing country populations, particularly in small island states, arid and high mountain zones, and in densely populated coastal areas are considered to be particularly vulnerable. India is a large developing country, with the Great Himalayas, the world's third largest ice mass in the north, 7500 km long, and densely populated coast line in the south. Nearly 700 million of her over one billion population living in rural areas directly depends on climate-sensitive sectors (agriculture, forests, and fisheries) and natural resources (such as water, biodiversity, mangroves, coastal zones, grasslands) for their subsistence and livelihoods. Heat wave, floods (land and coastal), and draughts occur commonly. Malaria, malnutrition, and diarrhea are major public health problems. Any further increase, as projected in weather-related disasters and related health effects, may cripple the already inadequate public health infrastructure in the country. Hence, there is an urgent need to respond to the situation. Response options to protect health from effects of climate change include mitigation as well as adaptation. Both can complement each other and together can significantly reduce the risks of climate change.

Toward a better understanding of the impact of mass transit air pollutants on human health.

PubMed

Kim, Ki-Hyun; Kumar, Pawan; Szulejko, Jan E; Adelodun, Adedeji A; Junaid, Muhammad Faisal; Uchimiya, Minori; Chambers, Scott

2017-05-01

Globally, modern mass transport systems whether by road, rail, water, or air generate airborne pollutants in both developing and developed nations. Air pollution is the primary human health concern originating from modern transportation, particularly in densely-populated urban areas. This review will specifically focus on the origin and the health impacts of carbonaceous traffic-related air pollutants (TRAP), including particulate matter (PM), volatile organic compounds (VOCs), and elemental carbon (EC). We conclude that the greatest current challenge regarding urban TRAP is understanding and evaluating the human health impacts well enough to set appropriate pollution control measures. Furthermore, we provide a detailed discussion regarding the effects of TRAP on local environments and pedestrian health in low and high traffic-density environments. Copyright © 2017 Elsevier Ltd. All rights reserved.

Density of the Human Body in Gravity Contrasting Tectonic Blocks of Earth

NASA Astrophysics Data System (ADS)

Kochemasov, G. G.

Short duration cosmic experiments with humans in reduced gravity might be compared with results of practically time unlimited (many thousand of years!) existence of man in conditions of planetary tectonic blocks with rather small gravity gradient. These blocks with differing planetary radii are formed in the terrestrial globe (as well as in other celestial bodies) as a result of its movement in an elliptical orbit inevitably causing inertia-gravity warping waves. Depending on the wavelengths, Earth is tectonically dichotomic (wave1, 2π R-structure), sectoral (wave2, π R-structure) and granular (wave4, π R/2-structure) [1]. Alternations of uplifts (+) and subsidences (-) in rotating Earth requires an equilibration of angular momenta of different levels blocks by differing densities of composing them objects. ``Objects'' are geological as well as biological ones. Oceans (-) are filled with dense basaltic rocks, continents (+) are built by less dense granites (andesites, on average). Homo sapiens, widely spread over Earth, equally accommodates himself to conditions of tectonic blocks with differing radii (densities). The most pronounced (amplitudinal) tectonic dichotomy is an opposition of the subsided (-) western pacific hemisphere to the uplifted (+) eastern continental hemisphere. Recently populated (12 to 3 thousand years ago) America and Pacific made migrating mongoloids denser (higher the Rohrer's index* of Indians and Polynesians) than inhabitants of native Asia. Asia itself is a sector of the planetary sectoral π R-structure of the eastern hemisphere with the center at the Pamirs-Hindukush. Around this center converge 2 uplifted sectors (Africa-Mediterranean ++, Asian +) separated by 2 subsided ones (Eurasian -, Indoceanic - -). The 4 great races developed on these sectors have their own ``body density'' characteristics. The uplifted Africa bears ``light'' negroids, subsided Eurasia ``heavy'' europeoids. In the former USSR population of the Asian sector (+) has less mineralized bones and less Fe/Mn in hairs (thus less dense hairs) than population of the Eurasian sector (-) [2]. The differentiation of the great races can be traced to the gene level: frequencies of their Rh-system genetic markers are clearly different. the ratio of man's weight to his height in the cube power (can be used also the simple ratio of man's weight to his height, that means the ``linear density'' of man). References : [1] Kochemasov G. G. Theorems of wave planetary tectonics // Geophys. Res. Abstr., V. 1, # 3, 1999,700; [2] Alexeeva T. I. Geographical environment and human biology // Moscow, Mysl, 1977, 302 pp. (in Russian).

Extreme Environment Basing:Contingency Basing in Dense Urban and Megacity Environments

DTIC Science & Technology

2016-05-24

the placement of a U.S. military contingency base. As stated above, the consideration given to the volume of displaced people caused by the base camp...population density , Dhaka, Bangladesh ........................... 29 B-1 The base camp development planning process...urban areas are not incredibly dense, a great many are. These places represent the extreme end of the urban spectrum for population density and city

Incomplete lineage sorting patterns among human, chimpanzee, and orangutan suggest recent orangutan speciation and widespread selection

PubMed Central

Hobolth, Asger; Dutheil, Julien Y.; Hawks, John; Schierup, Mikkel H.; Mailund, Thomas

2011-01-01

We search the complete orangutan genome for regions where humans are more closely related to orangutans than to chimpanzees due to incomplete lineage sorting (ILS) in the ancestor of human and chimpanzees. The search uses our recently developed coalescent hidden Markov model (HMM) framework. We find ILS present in ∼1% of the genome, and that the ancestral species of human and chimpanzees never experienced a severe population bottleneck. The existence of ILS is validated with simulations, site pattern analysis, and analysis of rare genomic events. The existence of ILS allows us to disentangle the time of isolation of humans and orangutans (the speciation time) from the genetic divergence time, and we find speciation to be as recent as 9–13 million years ago (Mya; contingent on the calibration point). The analyses provide further support for a recent speciation of human and chimpanzee at ∼4 Mya and a diverse ancestor of human and chimpanzee with an effective population size of about 50,000 individuals. Posterior decoding infers ILS for each nucleotide in the genome, and we use this to deduce patterns of selection in the ancestral species. We demonstrate the effect of background selection in the common ancestor of humans and chimpanzees. In agreement with predictions from population genetics, ILS was found to be reduced in exons and gene-dense regions when we control for confounding factors such as GC content and recombination rate. Finally, we find the broad-scale recombination rate to be conserved through the complete ape phylogeny. PMID:21270173

Relative effects of climatic and local factors on fire occurrence in boreal forest landscapes of northeastern China.

PubMed

Wu, Zhiwei; He, Hong S; Yang, Jian; Liu, Zhihua; Liang, Yu

2014-09-15

Fire significantly affects species composition, structure, and ecosystem processes in boreal forests. Our study objective was to identify the relative effects of climate, vegetation, topography, and human activity on fire occurrence in Chinese boreal forest landscapes. We used historical fire ignition for 1966-2005 and the statistical method of Kernel Density Estimation to derive fire-occurrence density (number of fires/km(2)). The Random Forest models were used to quantify the relative effects of climate, vegetation, topography, and human activity on fire-occurrence density. Our results showed that fire-occurrence density tended to be spatially clustered. Human-caused fire occurrence was highly clustered at the southern part of the region, where human population density is high (comprising about 75% of the area's population). In the north-central areas where elevations are the highest in the region and less densely populated, lightning-caused fires were clustered. Climate factors (e.g., fine fuel and duff moisture content) were important at both regional and landscape scales. Human activity factors (e.g., distance to nearest settlement and road) were secondary to climate as the primary fire occurrence factors. Predictions of fire regimes often assume a strong linkage between climate and fire but usually with less emphasis placed on the effects of local factors such as human activity. We therefore suggest that accurate forecasting of fire regime should include human influences such as those measured by forest proximity to roads and human settlements. Copyright © 2014 Elsevier B.V. All rights reserved.

Vulnerability of populations and man-made facilities to seismic hazards

NASA Astrophysics Data System (ADS)

Badal, J.; Vazquez-Prada, M.; Gonzalez, A.; Chourak, M.; Samardzhieva, E.; Zhang, Z.

2003-04-01

Earthquakes become major societal risks when they impinge on vulnerable populations. According to the available worldwide data during the twentieth century (NEIC Catalog of Earthquakes 1980-1999), almost half a thousand of earthquakes resulted in more than 1,615,000 human victims. Besides human casualty levels, destructive earthquakes frequently inflict huge economic losses. An additional problem of very different nature, but also worthy of being considered in a damage and loss analysis, is the direct cost associated with the damages derived from a strong seismic impact. We focus our attention on both aspects to their rapid quantitative assessment, and to lessen the earthquake disaster in areas affected by relatively strong earthquakes. Our final goal is the knowledge of potential losses from earthquakes to forward national programs in emergency management, and consequently the minimization of the life loss due to earthquakes, and to aid in response and recovery tasks. For this purpose we follow a suitable and comprehensible methodology for risk-based loss analysis, and simulate the occurence of a seismic event in densely populated areas of Spain.

Conservation issues: California chaparral

USGS Publications Warehouse

Halsey, Richard W.; Keeley, Jon E.

2016-01-01

California chaparral, a sclerophyllous shrub-dominated plant community shaped by a Mediterranean-type climate and infrequent, high-intensity fire, is one of the most biodiverse and threatened habitats on Earth. Distinct forms of chaparral, distinguished by differing species composition, geography, and edaphic characteristics, can cover thousands of hectares with dense vegetation or be restricted to smaller communities identified by the presence of endemic species. To maintain the biodiversity of chaparral, protective land management actions will be required to mitigate the loss due to the impacts of human population growth, development, climate change, and increased fire frequencies.

The VIMOS Public Extragalactic Redshift Survey (VIPERS). The distinct build-up of dense and normal massive passive galaxies

NASA Astrophysics Data System (ADS)

Gargiulo, A.; Bolzonella, M.; Scodeggio, M.; Krywult, J.; De Lucia, G.; Guzzo, L.; Garilli, B.; Granett, B. R.; de la Torre, S.; Abbas, U.; Adami, C.; Arnouts, S.; Bottini, D.; Cappi, A.; Cucciati, O.; Davidzon, I.; Franzetti, P.; Fritz, A.; Haines, C.; Hawken, A. J.; Iovino, A.; Le Brun, V.; Le Fèvre, O.; Maccagni, D.; Małek, K.; Marulli, F.; Moutard, T.; Polletta, M.; Pollo, A.; Tasca, L. A. M.; Tojeiro, R.; Vergani, D.; Zanichelli, A.; Zamorani, G.; Bel, J.; Branchini, E.; Coupon, J.; Ilbert, O.; Moscardini, L.; Peacock, J. A.

2017-10-01

We have used the final data from the VIPERS redshift survey to extract an unparalleled sample of more than 2000 massive ℳ≥1011 M⊙ passive galaxies (MPGs) at redshift 0.5≤z≤1.0, based on their NUVrK colours. This has enabled us to investigate how the population of these objects was built up over cosmic time. We find that the evolution of the number density depends on the galaxy mean surface stellar mass density, Σ. In particular, dense (Σ≥2000 M⊙ pc-2) MPGs show a constant comoving number density over this redshift range, whilst this increases by a factor of approximately four for the least dense objects, defined as having Σ < 1000 M⊙ pc-2. We estimated stellar ages for the MPG population both fitting the spectral energy distribution (SED) and through the D4000n index, obtaining results in good agreement. Our findings are consistent with passive ageing of the stellar content of dense MPGs. We show that at any redshift the less dense MPGs are younger than dense ones and that their stellar populations evolve at a slower rate than predicted by passive evolution. This points to a scenario in which the overall population of MPGs was built up over the cosmic time by continuous addition of less dense galaxies: on top of an initial population of dense objects that passively evolves, new, larger, and younger MPGs continuously join the population at later epochs. Finally, we demonstrate that the observed increase in the number density of MPGs is totally accounted for by the observed decrease in the number density of correspondingly massive star forming galaxies (I.e. all the non-passive ℳ≥1011 M⊙ objects). Such systems observed at z ≃ 1 in VIPERS, therefore, represent the most plausible progenitors of the subsequent emerging class of larger MPGs. Based on observations collected at the European Southern Observatory, Cerro Paranal, Chile, using the Very Large Telescope under programs 182.A-0886 and partly 070.A-9007. Also based on observations obtained with MegaPrime/MegaCam, a joint project of CFHT and CEA/DAPNIA, at the Canada-France-Hawaii Telescope (CFHT), which is operated by the National Research Council (NRC) of Canada, the Institut National des Sciences de l'Univers of the Centre National de la Recherche Scientifique (CNRS) of France, and the University of Hawaii. This work is based in part on data products produced at TERAPIX and the Canadian Astronomy Data Centre as part of the Canada-France-Hawaii Telescope Legacy Survey, a collaborative project of NRC and CNRS. The VIPERS web site is http://www.vipers.inaf.it/

The roles of large top predators in coastal ecosystems: new insights from long term ecological research

USGS Publications Warehouse

Rosenblatt, Adam E.; Heithaus, Michael R.; Mather, Martha E.; Matich, Philip; Nifong, James C.; Ripple, William J.; Silliman, Brian R.

2013-01-01

During recent human history, human activities such as overhunting and habitat destruction have severely impacted many large top predator populations around the world. Studies from a variety of ecosystems show that loss or diminishment of top predator populations can have serious consequences for population and community dynamics and ecosystem stability. However, there are relatively few studies of the roles of large top predators in coastal ecosystems, so that we do not yet completely understand what could happen to coastal areas if large top predators are extirpated or significantly reduced in number. This lack of knowledge is surprising given that coastal areas around the globe are highly valued and densely populated by humans, and thus coastal large top predator populations frequently come into conflict with coastal human populations. This paper reviews what is known about the ecological roles of large top predators in coastal systems and presents a synthesis of recent work from three coastal eastern US Long Term Ecological Research (LTER) sites where long-term studies reveal what appear to be common themes relating to the roles of large top predators in coastal systems. We discuss three specific themes: (1) large top predators acting as mobile links between disparate habitats, (2) large top predators potentially affecting nutrient and biogeochemical dynamics through localized behaviors, and (3) individual specialization of large top predator behaviors. We also discuss how research within the LTER network has led to enhanced understanding of the ecological roles of coastal large top predators. Highlighting this work is intended to encourage further investigation of the roles of large top predators across diverse coastal aquatic habitats and to better inform researchers and ecosystem managers about the importance of large top predators for coastal ecosystem health and stability.

Cougar response to a gradient of human development

DOE PAGES

Maletzke, Benjamin; Kertson, Brian; Swanson, Mark; ...

2017-07-07

Human populations continue to increase and transform Earth's ecosystems. For large carnivores, human development reduces habitat abundance, alters predator–prey dynamics, and increases the risk of mortality, which may threaten the viability of many populations. To investigate how the cougar ( Puma concolor) responds to a gradient of human development in four areas in Washington, USA, we used utilization distributions, county tax parcel data, Weibull modeling analysis, and multiple comparison techniques. Cougars used wildland areas the majority of the time (79% ± 2%, n = 112 cougars), with use decreasing as housing densities increased. When present in human-developed areas in easternmore » Washington, 99% of the habitat that cougars used had housing densities ≤76.5 residences/km 2, which was <846.0 residences/km 2 observed in western Washington ( P < 0.01). Cougars used areas in western Washington with greater housing density likely because of the clustered nature of housing developments, the connectivity with greenbelts and forested corridors, and security cover of dense maritime vegetation. Our findings suggest a consistent, albeit nuanced response by cougars to human development that may be used by wildlife managers, landscape planners, and environmental educators to guide and enhance their efforts to minimize the impacts of human development on cougars and reduce the potential for conflicts with people. In conclusion, our model may also provide guidance for thresholds of human development for other adaptable large carnivores.« less

Cougar response to a gradient of human development

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

Maletzke, Benjamin; Kertson, Brian; Swanson, Mark

Human populations continue to increase and transform Earth's ecosystems. For large carnivores, human development reduces habitat abundance, alters predator–prey dynamics, and increases the risk of mortality, which may threaten the viability of many populations. To investigate how the cougar ( Puma concolor) responds to a gradient of human development in four areas in Washington, USA, we used utilization distributions, county tax parcel data, Weibull modeling analysis, and multiple comparison techniques. Cougars used wildland areas the majority of the time (79% ± 2%, n = 112 cougars), with use decreasing as housing densities increased. When present in human-developed areas in easternmore » Washington, 99% of the habitat that cougars used had housing densities ≤76.5 residences/km 2, which was <846.0 residences/km 2 observed in western Washington ( P < 0.01). Cougars used areas in western Washington with greater housing density likely because of the clustered nature of housing developments, the connectivity with greenbelts and forested corridors, and security cover of dense maritime vegetation. Our findings suggest a consistent, albeit nuanced response by cougars to human development that may be used by wildlife managers, landscape planners, and environmental educators to guide and enhance their efforts to minimize the impacts of human development on cougars and reduce the potential for conflicts with people. In conclusion, our model may also provide guidance for thresholds of human development for other adaptable large carnivores.« less

Hi-Tech for Archeology

NASA Technical Reports Server (NTRS)

1987-01-01

Remote sensing is the process of acquiring physical information from a distance, obtaining data on Earth features from a satellite or an airplane. Advanced remote sensing instruments detect radiations not visible to the ordinary camera or the human eye in several bands of the spectrum. These data are computer processed to produce multispectral images that can provide enormous amounts of information about Earth objects or phenomena. Since every object on Earth emits or reflects radiation in its own unique signature, remote sensing data can be interpreted to tell the difference between one type of vegetation and another, between densely populated urban areas and lightly populated farmland, between clear and polluted water or in the archeological application between rain forest and hidden man made structures.

Genomic signatures of positive selection in humans and the limits of outlier approaches.

PubMed

Kelley, Joanna L; Madeoy, Jennifer; Calhoun, John C; Swanson, Willie; Akey, Joshua M

2006-08-01

Identifying regions of the human genome that have been targets of positive selection will provide important insights into recent human evolutionary history and may facilitate the search for complex disease genes. However, the confounding effects of population demographic history and selection on patterns of genetic variation complicate inferences of selection when a small number of loci are studied. To this end, identifying outlier loci from empirical genome-wide distributions of genetic variation is a promising strategy to detect targets of selection. Here, we evaluate the power and efficiency of a simple outlier approach and describe a genome-wide scan for positive selection using a dense catalog of 1.58 million SNPs that were genotyped in three human populations. In total, we analyzed 14,589 genes, 385 of which possess patterns of genetic variation consistent with the hypothesis of positive selection. Furthermore, several extended genomic regions were found, spanning >500 kb, that contained multiple contiguous candidate selection genes. More generally, these data provide important practical insights into the limits of outlier approaches in genome-wide scans for selection, provide strong candidate selection genes to study in greater detail, and may have important implications for disease related research.

[Object-oriented remote sensing image classification in epidemiological studies of visceral leishmaniasis in urban areas].

PubMed

Almeida, Andréa Sobral de; Werneck, Guilherme Loureiro; Resendes, Ana Paula da Costa

2014-08-01

This study explored the use of object-oriented classification of remote sensing imagery in epidemiological studies of visceral leishmaniasis (VL) in urban areas. To obtain temperature and environmental information, an object-oriented classification approach was applied to Landsat 5 TM scenes from the city of Teresina, Piauí State, Brazil. For 1993-1996, VL incidence rates correlated positively with census tracts covered by dense vegetation, grass/pasture, and bare soil and negatively with areas covered by water and densely populated areas. In 2001-2006, positive correlations were found with dense vegetation, grass/pasture, bare soil, and densely populated areas and negative correlations with occupied urban areas with some vegetation. Land surface temperature correlated negatively with VL incidence in both periods. Object-oriented classification can be useful to characterize landscape features associated with VL in urban areas and to help identify risk areas in order to prioritize interventions.

Combining environment and health information systems for the assessment of atmospheric pollution on human health.

PubMed

Skouloudis, Andreas N; Kassomenos, Pavlos

2014-08-01

The use of emerging technologies for environmental monitoring with satellite and in-situ sensors have become essential instruments for assessing the impact of environmental pollution on human health, especially in areas that require high spatial and temporal resolution. This was until recently a rather difficult problem. Regrettably, with classical approaches the spatial resolution is frequently inadequate in reporting environmental causes and health effects in the same time scale. This work examines with new tools different levels of air-quality with sensor monitoring with the aim to associate those with severe health effects. The process established here facilitates the precise representation of human exposure with the population attributed in a fine spatial grid and taking into account environmental stressors of human exposure. These stressors can be monitored with innovative sensor units with a temporal resolution that accurately describes chronic and acute environmental burdens. The current understanding of the situation in densely populated areas can be properly analyzed, before commitments are made for reductions in total emissions as well as for assessing the effects of reduced trans-boundary fluxes. In addition, the data processed here with in-situ sensors can assist in establishing more effective regulatory policies for the protection of vulnerable population groups and the satellite monitoring instruments permit abatement strategies that are close to real-time over large geographical areas. Copyright © 2014 Elsevier B.V. All rights reserved.

A review of the basic concepts of dense gas dispersion with special regard to modelling of heat transfer

NASA Astrophysics Data System (ADS)

Tasker, M. N.

1984-01-01

Dense gas dispersion is the study of the spreading and dilution of a gas that has a density greater than that of ambient air. Models to predict the dispersion of such dense gases as chlorine, sulfur dioxide, liquefied natural gas, and liquid propane are necessary to prevent a catastrophe in environmental and/or human terms. A basic physical picture of dense gas dispersion is provided. Mathematical and wind tunnel models of dense gas flow are presented and discussed, including the constraints and disadvantages of modelling techniques. Special emphasis is given to heat transfer during dense gas dispersion.

Human impacts on 20th century fire dynamics and implications for global carbon and water trajectories

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

Li, Fang; Lawrence, David M.; Bond-Lamberty, Ben

Fire is a fundamental Earth system process and the primary ecosystem disturbance on the global scale. It affects carbon and water cycles through changing terrestrial ecosystems, and at the same time, is regulated by weather and climate, vegetation characteristics, and, importantly, human ignitions and suppression (i.e., the direct human effect on fire). Here, we utilize the Community Land Model version 4.5 (CLM4.5) to quantify the impacts of changes in human ignition and suppression on fire dynamics and associated carbon and water cycles. We find that the impact is to significantly reduce the 20th century global burned area by a centurymore » average of 38 Mha/yr and by 103 Mha/yr at the end of the century. Land carbon gain is weakened by 17% over the 20th century, mainly due to increased human deforestation fires and associated escape fires (i.e., degradation fires) in the tropical humid forests, even though the decrease in burned area in many other regions due to human fire suppression acts to increase land carbon gain. The direct human effect on fire weakens the upward trend in global runoff throughout the century by 6% and enhances the upward trend in global evapotranspiration since ~ 1945 by 7%. In addition, the above impacts in densely populated, highly developed (if population density > 0.1 person/km2), or moderately populated and developed regions are of opposite sign to those in other regions. Our study suggests that particular attention should be paid to human deforestation and degradation fires in the tropical humid forests when reconstructing and projecting fire carbon emissions and net atmosphere-land carbon exchange and estimating resultant impacts of direct human effect on fire.« less

Human impacts on 20th century fire dynamics and implications for global carbon and water trajectories

NASA Astrophysics Data System (ADS)

Li, Fang; Lawrence, David M.; Bond-Lamberty, Ben

2018-03-01

Fire is a fundamental Earth system process and the primary ecosystem disturbance on the global scale. It affects carbon and water cycles through changing terrestrial ecosystems, and at the same time, is regulated by weather and climate, vegetation characteristics, and, importantly, human ignitions and suppression (i.e., the direct human effect on fire). Here, we utilize the Community Land Model version 4.5 (CLM4.5) to quantify the impacts of changes in human ignition and suppression on fire dynamics and associated carbon and water cycles. We find that the impact is to significantly reduce the 20th century global burned area by a century average of 38 Mha/yr and by 103 Mha/yr at the end of the century. Land carbon gain is weakened by 17% over the 20th century, mainly due to increased human deforestation fires and associated escape fires (i.e., degradation fires) in the tropical humid forests, even though the decrease in burned area in many other regions due to human fire suppression acts to increase land carbon gain. The direct human effect on fire weakens the upward trend in global runoff throughout the century by 6% and enhances the upward trend in global evapotranspiration since 1945 by 7%. In addition, the above impacts in densely populated, highly developed (if population density > 0.1 person/km2), or moderately populated and developed regions are of opposite sign to those in other regions. Our study suggests that particular attention should be paid to human deforestation and degradation fires in the tropical humid forests when reconstructing and projecting fire carbon emissions and net atmosphere-land carbon exchange and estimating resultant impacts of direct human effect on fire.

Distribution and sediment production of large benthic foraminifers on reef flats of the Majuro Atoll, Marshall Islands

NASA Astrophysics Data System (ADS)

Fujita, K.; Osawa, Y.; Kayanne, H.; Ide, Y.; Yamano, H.

2009-03-01

The distributions and population densities of large benthic foraminifers (LBFs) were investigated on reef flats of the Majuro Atoll, Marshall Islands. Annual sediment production by foraminifers was estimated based on population density data. Predominant LBFs were Calcarina and Amphistegina, and the population densities of these foraminifers varied with location and substratum type on reef flats. Both foraminifers primarily attached to macrophytes, particularly turf-forming algae, and were most abundant on an ocean reef flat (ORF) and in an inter-island channel near windward, sparsely populated islands. Calcarina density was higher on windward compared to leeward sides of ORFs, whereas Amphistegina density was similar on both sides of ORFs. These foraminifers were more common on the ocean side relative to the lagoon side of reef flats around a windward reef island, and both were rare or absent in nearshore zones around reef islands and on an ORF near windward, densely populated islands. Foraminiferal production rates varied with the degree to which habitats were subject to water motion and human influences. Highly productive sites (>103 g CaCO3 m-2 year-1) included an ORF and an inter-island channel near windward, sparsely populated islands, and a seaward area of a reef flat with no reef islands. Low-productivity sites (<10 g CaCO3 m-2 year-1) included generally nearshore zones of lagoonal reef flats, leeward ORFs, and a windward ORF near densely populated islands. These results suggest that the distribution and production of LBFs were largely influenced by a combination of natural environmental factors, including water motion, water depth, elevation relative to the lowest tidal level at spring tide, and the distribution of suitable substratum. The presence of reef islands may limit the distribution and production of foraminifers by altering water circulation in nearshore environments. Furthermore, increased anthropogenic factors (population and activities) may adversely affect foraminiferal distribution and production.

Speciation and dynamics of dissolved inorganic nitrogen export in the Danshui River, Taiwan

NASA Astrophysics Data System (ADS)

Lee, T.-Y.; Shih, Y.-T.; Huang, J.-C.; Kao, S.-J.; Shiah, F.-K.; Liu, K.-K.

2014-10-01

Human-induced excess nitrogen outflowing from land through rivers to oceans has resulted in serious impacts on terrestrial and coastal ecosystems. Oceania, which occupies < 2.5% of the global land surface, delivers 12% of the freshwater and dissolved materials to the ocean on a global scale. However, there are few empirical data sets on riverine dissolved inorganic nitrogen (DIN) fluxes in the region, and their dynamics are poorly understood. In this study, a river monitoring network covering different types of land uses and population densities was implemented to investigate the mechanism of DIN export. The results show that DIN concentration/yield varied from ∼20 μM/∼300 kg-N km-2 yr-1 to ∼378 μM/∼10 000 kg-N km-2 yr-1 from the relatively pristine headwaters to the populous estuary. Agriculture and population density control DIN export in less densely populated regions and urban areas, respectively, and runoff controls DIN at the watershed scale. Compared to documented estimates from global models, the observed DIN export from the Danshui River is 2.3 times larger, which results from the region-specific response of DIN yield to dense population and abundant runoff. The dominating DIN species change gradually from NO3- in the headwaters (∼97%) to NH4+ in the estuary (∼60%) following the urbanization gradient. The prominent existence of NH4+ is probably the result of the anaerobic water body and short residence time, unlike in large river basins. Given the analogous watershed characteristics of the Danshui River to the rivers in Oceania, our study could serve as a first example to examine riverine DIN fluxes in Oceania.

Does the Orphan Disadvantage “Spill Over?” An analysis of whether living in an area with a higher concentration of orphans is associated with children’s school enrollment in sub-Saharan Africa

PubMed Central

Smith-Greenaway, Emily; Heckert, Jessica

2013-01-01

BACKGROUND Despite considerable concern regarding the social consequences of sub-Saharan Africa’s high orphan prevalence, no research investigates how living in a community densely populated with orphans is more broadly associated with children’s—including nonorphans’—acquisition of human capital. OBJECTIVE We provide a new look at the implications of widespread orphanhood in sub-Saharan Africa by examining whether living in an area with a high concentration of orphans is associated with children’s likelihood of school enrollment. METHODS We use data from the Demographic and Health Survey (DHS) and the Multiple Indicators Cluster Survey (MICS) to estimate multilevel logistic regression models to assess whether living in a setting with a higher concentration of orphans is associated with school enrollment among 383,010 children in 336 provinces in 34 sub-Saharan African countries. RESULTS Orphan concentration has a curvilinear association with children’s school enrollment in western and eastern Africa: the initially positive association becomes negative at higher levels. In central and southern Africa, orphan concentration has a positive linear association with children’s school enrollment. CONCLUSION In western and eastern Africa, the negative association between living in a setting more densely populated with orphans and children’s school enrollment provides suggestive evidence that the orphan disadvantage “spills over” in the communities most heavily affected. Conversely, in central and southern Africa, the positive association between living in a setting more densely populated with orphans and children’s school enrollment highlights the resiliency of these relatively wealthier communities with high levels of orphans. Although longitudinal research is needed to confirm these findings and clarify the underlying mechanisms, this study lays the groundwork for a new body of research aimed at understanding the broader social implications of widespread orphanhood in sub-Saharan Africa. PMID:24062628

The transition to foraging for dense and predictable resources and its impact on the evolution of modern humans.

PubMed

Marean, Curtis W

2016-07-05

Scientists have identified a series of milestones in the evolution of the human food quest that are anticipated to have had far-reaching impacts on biological, behavioural and cultural evolution: the inclusion of substantial portions of meat, the broad spectrum revolution and the transition to food production. The foraging shift to dense and predictable resources is another key milestone that had consequential impacts on the later part of human evolution. The theory of economic defendability predicts that this shift had an important consequence-elevated levels of intergroup territoriality and conflict. In this paper, this theory is integrated with a well-established general theory of hunter-gatherer adaptations and is used to make predictions for the sequence of appearance of several evolved traits of modern humans. The distribution of dense and predictable resources in Africa is reviewed and found to occur only in aquatic contexts (coasts, rivers and lakes). The palaeoanthropological empirical record contains recurrent evidence for a shift to the exploitation of dense and predictable resources by 110 000 years ago, and the first known occurrence is in a marine coastal context in South Africa. Some theory predicts that this elevated conflict would have provided the conditions for selection for the hyperprosocial behaviours unique to modern humans.This article is part of the themed issue 'Major transitions in human evolution'. © 2016 The Author(s).

The transition to foraging for dense and predictable resources and its impact on the evolution of modern humans

PubMed Central

Marean, Curtis W.

2016-01-01

Scientists have identified a series of milestones in the evolution of the human food quest that are anticipated to have had far-reaching impacts on biological, behavioural and cultural evolution: the inclusion of substantial portions of meat, the broad spectrum revolution and the transition to food production. The foraging shift to dense and predictable resources is another key milestone that had consequential impacts on the later part of human evolution. The theory of economic defendability predicts that this shift had an important consequence—elevated levels of intergroup territoriality and conflict. In this paper, this theory is integrated with a well-established general theory of hunter–gatherer adaptations and is used to make predictions for the sequence of appearance of several evolved traits of modern humans. The distribution of dense and predictable resources in Africa is reviewed and found to occur only in aquatic contexts (coasts, rivers and lakes). The palaeoanthropological empirical record contains recurrent evidence for a shift to the exploitation of dense and predictable resources by 110 000 years ago, and the first known occurrence is in a marine coastal context in South Africa. Some theory predicts that this elevated conflict would have provided the conditions for selection for the hyperprosocial behaviours unique to modern humans. This article is part of the themed issue ‘Major transitions in human evolution’. PMID:27298470

Clustering of 770,000 genomes reveals post-colonial population structure of North America

NASA Astrophysics Data System (ADS)

Han, Eunjung; Carbonetto, Peter; Curtis, Ross E.; Wang, Yong; Granka, Julie M.; Byrnes, Jake; Noto, Keith; Kermany, Amir R.; Myres, Natalie M.; Barber, Mathew J.; Rand, Kristin A.; Song, Shiya; Roman, Theodore; Battat, Erin; Elyashiv, Eyal; Guturu, Harendra; Hong, Eurie L.; Chahine, Kenneth G.; Ball, Catherine A.

2017-02-01

Despite strides in characterizing human history from genetic polymorphism data, progress in identifying genetic signatures of recent demography has been limited. Here we identify very recent fine-scale population structure in North America from a network of over 500 million genetic (identity-by-descent, IBD) connections among 770,000 genotyped individuals of US origin. We detect densely connected clusters within the network and annotate these clusters using a database of over 20 million genealogical records. Recent population patterns captured by IBD clustering include immigrants such as Scandinavians and French Canadians; groups with continental admixture such as Puerto Ricans; settlers such as the Amish and Appalachians who experienced geographic or cultural isolation; and broad historical trends, including reduced north-south gene flow. Our results yield a detailed historical portrait of North America after European settlement and support substantial genetic heterogeneity in the United States beyond that uncovered by previous studies.

Clustering of 770,000 genomes reveals post-colonial population structure of North America

PubMed Central

Han, Eunjung; Carbonetto, Peter; Curtis, Ross E.; Wang, Yong; Granka, Julie M.; Byrnes, Jake; Noto, Keith; Kermany, Amir R.; Myres, Natalie M.; Barber, Mathew J.; Rand, Kristin A.; Song, Shiya; Roman, Theodore; Battat, Erin; Elyashiv, Eyal; Guturu, Harendra; Hong, Eurie L.; Chahine, Kenneth G.; Ball, Catherine A.

2017-01-01

Despite strides in characterizing human history from genetic polymorphism data, progress in identifying genetic signatures of recent demography has been limited. Here we identify very recent fine-scale population structure in North America from a network of over 500 million genetic (identity-by-descent, IBD) connections among 770,000 genotyped individuals of US origin. We detect densely connected clusters within the network and annotate these clusters using a database of over 20 million genealogical records. Recent population patterns captured by IBD clustering include immigrants such as Scandinavians and French Canadians; groups with continental admixture such as Puerto Ricans; settlers such as the Amish and Appalachians who experienced geographic or cultural isolation; and broad historical trends, including reduced north-south gene flow. Our results yield a detailed historical portrait of North America after European settlement and support substantial genetic heterogeneity in the United States beyond that uncovered by previous studies. PMID:28169989

Clustering of 770,000 genomes reveals post-colonial population structure of North America.

PubMed

Han, Eunjung; Carbonetto, Peter; Curtis, Ross E; Wang, Yong; Granka, Julie M; Byrnes, Jake; Noto, Keith; Kermany, Amir R; Myres, Natalie M; Barber, Mathew J; Rand, Kristin A; Song, Shiya; Roman, Theodore; Battat, Erin; Elyashiv, Eyal; Guturu, Harendra; Hong, Eurie L; Chahine, Kenneth G; Ball, Catherine A

2017-02-07

Despite strides in characterizing human history from genetic polymorphism data, progress in identifying genetic signatures of recent demography has been limited. Here we identify very recent fine-scale population structure in North America from a network of over 500 million genetic (identity-by-descent, IBD) connections among 770,000 genotyped individuals of US origin. We detect densely connected clusters within the network and annotate these clusters using a database of over 20 million genealogical records. Recent population patterns captured by IBD clustering include immigrants such as Scandinavians and French Canadians; groups with continental admixture such as Puerto Ricans; settlers such as the Amish and Appalachians who experienced geographic or cultural isolation; and broad historical trends, including reduced north-south gene flow. Our results yield a detailed historical portrait of North America after European settlement and support substantial genetic heterogeneity in the United States beyond that uncovered by previous studies.

Spatially explicit prioritization of human antibiotics and antineoplastics in Europe.

PubMed

Oldenkamp, Rik; Huijbregts, Mark A J; Hollander, Anne; Versporten, Ann; Goossens, Herman; Ragas, Ad M J

2013-01-01

This paper presents a screening tool for the location-specific prioritization of human pharmaceutical emissions in Europe, based on risk quotients for the aquatic environment and human health. The tool provides direction towards either monitoring activities or additional research. Its application is illustrated for a set of 11 human antibiotics and 7 antineoplastics. Risk quotients for the aquatic environment were highest for levofloxacin, doxycycline and ciprofloxacin, located in Northern Italy (Milan region; particularly levofloxacin) and other densely populated areas in Europe (e.g. London, Krakow and the Ruhr area). Risk quotients for human health not only depend on pharmaceutical and location, but also on behavioral characteristics, such as consumption patterns. Infants in eastern Spain that consume locally produced food and conventionally treated drinking water were predicted to run the highest risks. A limited comparison with measured concentrations in surface water showed that predicted and measured concentrations are approximately within one order of magnitude. Copyright © 2012 Elsevier Ltd. All rights reserved.

Complex chromosome aberrations persist in individuals many years after occupational exposure to densely ionizing radiation: an mFISH study.

PubMed

Hande, M Prakash; Azizova, Tamara V; Burak, Ludmilla E; Khokhryakov, Valentin F; Geard, Charles R; Brenner, David J

2005-09-01

Long-lived, sensitive, and specific biomarkers of particular mutagenic agents are much sought after and potentially have broad applications in the fields of cancer biology, epidemiology, and prevention. Many clastogens induce a spectrum of chromosome aberrations, and some of them can be exploited as biomarkers of exposure. Densely ionizing radiation, for example, alpha particle radiation (from radon or plutonium) and neutron radiation, preferentially induces complex chromosome aberrations, which can be detected by the 24-color multifluor fluorescence in situ hybridization (mFISH) technique. We report the detection and quantification of stable complex chromosome aberrations in lymphocytes of healthy former nuclear-weapons workers, who were exposed many years ago to plutonium, gamma rays, or both, at the Mayak weapons complex in Russia. We analyzed peripheral-blood lymphocytes from these individuals for the presence of persistent complex chromosome aberrations. A significantly elevated frequency of complex chromosome translocations was detected in the highly exposed plutonium workers but not in the group exposed only to high doses of gamma radiation. No such differences were found for simple chromosomal aberrations. The results suggest that stable complex chromosomal translocations represent a long-lived, quantitative, low-background biomarker of densely ionizing radiation for human populations exposed many years ago. (c) 2005 Wiley-Liss, Inc.

The effect of canopy closure on chimpanzee nest abundance in Lagoas de Cufada National Park, Guinea-Bissau.

PubMed

Sousa, Joana; Casanova, Catarina; Barata, André V; Sousa, Cláudia

2014-04-01

The present study aimed to gather baseline information about chimpanzee nesting and density in Lagoas de Cufada Natural Park (LCNP), in Guinea-Bissau. Old and narrow trails were followed to estimate chimpanzee density through marked-nest counts and to test the effect of canopy closure (woodland savannah, forest with a sparse canopy, and forest with a dense canopy) on nest distribution. Chimpanzee abundance was estimated at 0.79 nest builders/km(2), the lowest among the areas of Guinea-Bissau with currently studied chimpanzee populations. Our data suggest that sub-humid forest with a dense canopy accounts for significantly higher chimpanzee nest abundance (1.50 nests/km of trail) than sub-humid forest with a sparse canopy (0.49 nests/km of trail) or woodland savannah (0.30 nests/km of trail). Dense-canopy forests play an important role in chimpanzee nesting in the patchy and highly humanized landscape of LCNP. The tree species most frequently used for nesting are Dialium guineense (46%) and Elaeis guineensis (28%). E. guineensis contain nests built higher in the canopy, while D. guineense contain nests built at lower heights. Nests observed during baseline sampling and replications suggest seasonal variations in the tree species used for nest building.

High-Resolution Strain Analysis of the Human Heart with Fast-DENSE

NASA Astrophysics Data System (ADS)

Aletras, Anthony H.; Balaban, Robert S.; Wen, Han

1999-09-01

Single breath-hold displacement data from the human heart were acquired with fast-DENSE (fast displacement encoding with stimulated echoes) during systolic contraction at 2.5 × 2.5 mm in-plane resolution. Encoding strengths of 0.86-1.60 mm/π were utilized in order to extend the dynamic range of the phase measurements and minimize effects of physiologic and instrument noise. The noise level in strain measurements for both contraction and dilation corresponded to a strain value of 2.8%. In the human heart, strain analysis has sufficient resolution to reveal transmural variation across the left ventricular wall. Data processing required minimal user intervention and provided a rapid quantitative feedback. The intrinsic temporal integration of fast-DENSE achieves high accuracy at the expense of temporal resolution.

Human-Mediated Marine Dispersal Influences the Population Structure of Aedes aegypti in the Philippine Archipelago

PubMed Central

Fonzi, Eugenio; Higa, Yukiko; Bertuso, Arlene G.; Futami, Kyoko; Minakawa, Noboru

2015-01-01

Background Dengue virus (DENV) is an extraordinary health burden on global scale, but still lacks effective vaccine. The Philippines is endemic for dengue fever, but massive employment of insecticides favored the development of resistance mutations in its major vector, Aedes aegypti. Alternative vector control strategies consist in releasing artificially modified mosquitos in the wild, but knowledge on their dispersal ability is necessary for a successful implementation. Despite being documented that Ae. aegypti can be passively transported for long distances, no study to date has been aimed at understanding whether human marine transportation can substantially shape the migration patterns of this mosquito. With thousands of islands connected by a dense network of ships, the Philippines is an ideal environment to fill this knowledge gap. Methodology/principal findings Larvae of Ae. aegypti from 15 seaports in seven major islands of central-western Philippines were collected and genotyped at seven microsatellite loci. Low genetic structure and considerable gene flow was found in the area. Univariate and multivariate regression analyses suggested that anthropic factors (specifically the amount of processed cargo and human population density) can explain the observed population structure, while geographical distance was not correlated. Interestingly, cargo shipments seem to be more efficient than passenger ships in transporting Ae. aegypti. Bayesian clustering confirmed that Ae. aegypti from busy ports are more genetically similar, while populations from idle ports are relatively structured, regardless of the geographical distance that separates them. Conclusions/significance The results confirmed the pivotal role of marine human-mediated long-range dispersal in determining the population structure of Ae. aegypti. Hopefully corroborated by further research, the present findings could assist the design of more effective vector control strategies. PMID:26039311

Anthropogenic habitat disturbance and ecological divergence between incipient species of the malaria mosquito Anopheles gambiae.

PubMed

Kamdem, Colince; Tene Fossog, Billy; Simard, Frédéric; Etouna, Joachim; Ndo, Cyrille; Kengne, Pierre; Boussès, Philippe; Etoa, François-Xavier; Awono-Ambene, Parfait; Fontenille, Didier; Antonio-Nkondjio, Christophe; Besansky, Nora J; Costantini, Carlo

2012-01-01

Anthropogenic habitat disturbance is a prime cause in the current trend of the Earth's reduction in biodiversity. Here we show that the human footprint on the Central African rainforest, which is resulting in deforestation and growth of densely populated urban agglomerates, is associated to ecological divergence and cryptic speciation leading to adaptive radiation within the major malaria mosquito Anopheles gambiae. In southern Cameroon, the frequency of two molecular forms--M and S--among which reproductive isolation is strong but still incomplete, was correlated to an index of urbanisation extracted from remotely sensed data, expressed as the proportion of built-up surface in each sampling unit. The two forms markedly segregated along an urbanisation gradient forming a bimodal cline of ∼6-km width: the S form was exclusive to the rural habitat, whereas only the M form was present in the core of densely urbanised settings, co-occurring at times in the same polluted larval habitats of the southern house mosquito Culex quinquefasciatus--a species association that was not historically recorded before. Our results indicate that when humans create novel habitats and ecological heterogeneities, they can provide evolutionary opportunities for rapid adaptive niche shifts associated with lineage divergence, whose consequences upon malaria transmission might be significant.

Multiscale Spatial Modeling of Human Exposure from Local Sources to Global Intake.

PubMed

Wannaz, Cedric; Fantke, Peter; Jolliet, Olivier

2018-01-16

Exposure studies, used in human health risk and impact assessments of chemicals, are largely performed locally or regionally. It is usually not known how global impacts resulting from exposure to point source emissions compare to local impacts. To address this problem, we introduce Pangea, an innovative multiscale, spatial multimedia fate and exposure assessment model. We study local to global population exposure associated with emissions from 126 point sources matching locations of waste-to-energy plants across France. Results for three chemicals with distinct physicochemical properties are expressed as the evolution of the population intake fraction through inhalation and ingestion as a function of the distance from sources. For substances with atmospheric half-lives longer than a week, less than 20% of the global population intake through inhalation (median of 126 emission scenarios) can occur within a 100 km radius from the source. This suggests that, by neglecting distant low-level exposure, local assessments might only account for fractions of global cumulative intakes. We also study ∼10 000 emission locations covering France more densely to determine per chemical and exposure route which locations minimize global intakes. Maps of global intake fractions associated with each emission location show clear patterns associated with population and agriculture production densities.

Population density and youth antisocial behavior.

PubMed

Harden, K Paige; D'Onofrio, Brian M; Van Hulle, Carol; Turkheimer, Eric; Rodgers, Joseph L; Waldman, Irwin D; Lahey, Benjamin B

2009-08-01

Theoretical models concerning how neighborhood contexts adversely influence juvenile antisocial behavior frequently focus on urban neighborhoods; however, previous studies comparing urban and rural areas on the prevalence of youth antisocial behavior have yielded mixed results. The current study uses longitudinal data on the offspring of a nationally representative sample of mothers (N = 4,886) in the US. There was no relation between density and mother-reported child conduct problems across ages 4-13 years, but youth living in areas of greater population density exhibited more youth self-reported delinquency across 10-17 years. Families often moved to counties with greater or lesser population density, but longitudinal analyses treating population density as a time-varying covariate did not support the hypothesis that living in densely populated counties influenced youth delinquency. Rather, the association between population density and delinquency appears to be due to unmeasured selection variables that differ between families who live in more or less densely populated counties.

Dense module enumeration in biological networks

NASA Astrophysics Data System (ADS)

Tsuda, Koji; Georgii, Elisabeth

2009-12-01

Analysis of large networks is a central topic in various research fields including biology, sociology, and web mining. Detection of dense modules (a.k.a. clusters) is an important step to analyze the networks. Though numerous methods have been proposed to this aim, they often lack mathematical rigorousness. Namely, there is no guarantee that all dense modules are detected. Here, we present a novel reverse-search-based method for enumerating all dense modules. Furthermore, constraints from additional data sources such as gene expression profiles or customer profiles can be integrated, so that we can systematically detect dense modules with interesting profiles. We report successful applications in human protein interaction network analyses.

Influence of the finite linewidth of the laser radiation spectrum on the shape of the coherent population trapping resonance line in an optically dense medium with a buffer gas

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

Barantsev, K. A., E-mail: kostmann@yandex.ru; Popov, E. N.; Litvinov, A. N., E-mail: andrey.litvinov@mail.ru

2015-11-15

The theory of coherent population trapping resonance is developed for the finite linewidth of the laser radiation spectrum in an optically dense medium of Λ atoms in a cell with a buffer gas. Equations are derived for the atomic density matrix and laser emission spectrum transfer in a cell with working and buffer gases at a finite temperature. The dependence of the quality factor of coherent population trapping resonance on the linewidth of the laser radiation spectrum is studied by measuring transmitted radiation and fluorescence signals.

Cholinergic Interneurons Are Differentially Distributed in the Human Striatum

PubMed Central

Bernácer, Javier; Prensa, Lucía; Giménez-Amaya, José Manuel

2007-01-01

Background The striatum (caudate nucleus, CN, and putamen, Put) is a group of subcortical nuclei involved in planning and executing voluntary movements as well as in cognitive processes. Its neuronal composition includes projection neurons, which connect the striatum with other structures, and interneurons, whose main roles are maintaining the striatal organization and the regulation of the projection neurons. The unique electrophysiological and functional properties of the cholinergic interneurons give them a crucial modulating function on the overall striatal response. Methodology/Principle Findings This study was carried out using stereological methods to examine the volume and density (cells/mm3) of these interneurons, as visualized by choline acetyltransferase (ChAT) immunoreactivity, in the following territories of the CN and Put of nine normal human brains: 1) precommissural head; 2) postcommissural head; 3) body; 4) gyrus and 5) tail of the CN; 6) precommissural and 7) postcommissural Put. The distribution of ChAT interneurons was analyzed with respect to the topographical, functional and chemical territories of the dorsal striatum. The CN was more densely populated by cholinergic neurons than the Put, and their density increased along the anteroposterior axis of the striatum with the CN body having the highest neuronal density. The associative territory of the dorsal striatum was by far the most densely populated. The striosomes of the CN precommissural head and the postcommissural Put contained the greatest number of ChAT-ir interneurons. The intrastriosomal ChAT-ir neurons were abundant on the periphery of the striosomes throughout the striatum. Conclusions/Significance All these data reveal that cholinergic interneurons are differentially distributed in the distinct topographical and functional territories of the human dorsal striatum, as well as in its chemical compartments. This heterogeneity may indicate that the posterior aspects of the CN require a special integration of information by interneurons. Interestingly, these striatal regions have been very much left out in functional studies. PMID:18080007

A system for household enumeration and re-identification in densely populated slums to facilitate community research, education, and advocacy.

PubMed

Thomson, Dana R; Shitole, Shrutika; Shitole, Tejal; Sawant, Kiran; Subbaraman, Ramnath; Bloom, David E; Patil-Deshmukh, Anita

2014-01-01

We devised and implemented an innovative Location-Based Household Coding System (LBHCS) appropriate to a densely populated informal settlement in Mumbai, India. LBHCS codes were designed to double as unique household identifiers and as walking directions; when an entire community is enumerated, LBHCS codes can be used to identify the number of households located per road (or lane) segment. LBHCS was used in community-wide biometric, mental health, diarrheal disease, and water poverty studies. It also facilitated targeted health interventions by a research team of youth from Mumbai, including intensive door-to-door education of residents, targeted follow-up meetings, and a full census. In addition, LBHCS permitted rapid and low-cost preparation of GIS mapping of all households in the slum, and spatial summation and spatial analysis of survey data. LBHCS was an effective, easy-to-use, affordable approach to household enumeration and re-identification in a densely populated informal settlement where alternative satellite imagery and GPS technologies could not be used.

Population Growth and a Sustainable Environment.

ERIC Educational Resources Information Center

Mortimore, Michael; Tiffen, Mary

1994-01-01

Provides a history of farming practices in a densely populated area of Kenya where a recent study of the resource management practices showed positive, not negative, influences of increasing population density on both environmental conservation and productivity. (LZ)

The Slc35d3 gene, encoding an orphan nucleotide sugar transporter, regulates platelet-dense granules

PubMed Central

Chintala, Sreenivasulu; Tan, Jian; Gautam, Rashi; Rusiniak, Michael E.; Guo, Xiaoli; Li, Wei; Gahl, William A.; Huizing, Marjan; Spritz, Richard A.; Hutton, Saunie; Novak, Edward K.; Swank, Richard T.

2007-01-01

Platelet dense granules are lysosome-related organelles which contain high concentrations of several biologically important low-molecular-weight molecules. These include calcium, serotonin, adenine nucleotides, pyrophosphate, and polyphosphate, which are necessary for normal blood hemostasis. The synthesis of dense granules and other lysosome-related organelles is defective in inherited diseases such as Hermansky-Pudlak syndrome (HPS) and Chediak-Higashi syndrome (CHS). HPS and CHS mutations in 8 human and at least 16 murine genes have been identified. Previous studies produced contradictory findings for the function of the murine ashen (Rab27a) gene in platelet-dense granules. We have used a positional cloning approach with one line of ashen mutants to establish that a new mutation in a second gene, Slc35d3, on mouse chromosome 10 is the basis of this discrepancy. The platelet-dense granule defect is rescued in BAC transgenic mice containing the normal Slc35d3 gene. Thus, Slc35d3, an orphan member of a nucleotide sugar transporter family, specifically regulates the contents of platelet-dense granules. Unlike HPS or CHS genes, it has no apparent effect on other lysosome-related organelles such as melanosomes or lysosomes. The ash-Roswell mouse mutant is an appropriate model for human congenital-isolated delta-storage pool deficiency. PMID:17062724

Human impacts on 20th century fire dynamics and implications for global carbon and water trajectories

NASA Astrophysics Data System (ADS)

Li, F.; Lawrence, D. M.; Bond-Lamberty, B. P.

2017-12-01

Fire is a fundamental Earth system process and the primary ecosystem disturbance on the global scale. It affects carbon and water cycles through its impact on terrestrial ecosystems, and at the same time, is regulated by weather and climate, vegetation characteristics, and, importantly, human ignition and efforts to suppress fires (i.e., the direct human effect on fire). Here, we utilize the Community Land Model version 4.5 (CLM4.5) to generate a quantitative understanding of the impacts on fire dynamics and associated carbon and water cycling that can be attributed to changes in human ignition and suppression over the 20th century. We find that the net impact of increases in human ignition and suppression significantly reduce the 20th century averaged global burned area by 38 Mha/yr. The reduction increases since 1920, rising to 103 Mha/yr less burned area at the end of the century. Land carbon gain is weakened by 17% over the 20th century, mainly due to increased human deforestation fires and associated escape fires (i.e., degradation fires) in the tropical humid forests, even though the decrease in burned area in many other regions due to human fire suppression acts to increase land carbon gain. The direct human effect on fire also weakens the 20th century upward trend of global runoff by 6%, and enhances the upward trend in global evaportranspiration since 1945 by 7%. In addition, the above impacts in densely populated, highly developed (if population density > 0.1 person/km2), or moderately populated and developed regions are of opposite sign to those in other regions. Our study suggests that particular attention should be paid to human deforestation and degradation fires in the tropical humid forests when reconstructing and projecting fire carbon emissions and net atmosphere-land carbon exchange and estimating resultant impacts of direct human effect on fire.

The role of sleep spindles and slow-wave activity in integrating new information in semantic memory.

PubMed

Tamminen, Jakke; Lambon Ralph, Matthew A; Lewis, Penelope A

2013-09-25

Assimilating new information into existing knowledge is a fundamental part of consolidating new memories and allowing them to guide behavior optimally and is vital for conceptual knowledge (semantic memory), which is accrued over many years. Sleep is important for memory consolidation, but its impact upon assimilation of new information into existing semantic knowledge has received minimal examination. Here, we examined the integration process by training human participants on novel words with meanings that fell into densely or sparsely populated areas of semantic memory in two separate sessions. Overnight sleep was polysomnographically monitored after each training session and recall was tested immediately after training, after a night of sleep, and 1 week later. Results showed that participants learned equal numbers of both word types, thus equating amount and difficulty of learning across the conditions. Measures of word recognition speed showed a disadvantage for novel words in dense semantic neighborhoods, presumably due to interference from many semantically related concepts, suggesting that the novel words had been successfully integrated into semantic memory. Most critically, semantic neighborhood density influenced sleep architecture, with participants exhibiting more sleep spindles and slow-wave activity after learning the sparse compared with the dense neighborhood words. These findings provide the first evidence that spindles and slow-wave activity mediate integration of new information into existing semantic networks.

A Stable Urban Ecosystem

ERIC Educational Resources Information Center

Meier, Richard L.

1976-01-01

Describes a model for the future evolution of a stable ecosystem in a densely-populated society. Discusses designs for limiting population growth, resource-conserving settlements, and ways to feed growing cities. (MLH)

Diffuse colonies of human skin fibroblasts in relation to cellular senescence and proliferation.

PubMed

Zorin, Vadim; Zorina, Alla; Smetanina, Nadezhda; Kopnin, Pavel; Ozerov, Ivan V; Leonov, Sergey; Isaev, Artur; Klokov, Dmitry; Osipov, Andreyan N

2017-05-16

Development of personalized skin treatment in medicine and skin care may benefit from simple and accurate evaluation of the fraction of senescent skin fibroblasts that lost their proliferative capacity. We examined whether enriched analysis of colonies formed by primary human skin fibroblasts, a simple and widely available cellular assay, could reveal correlations with the fraction of senescent cells in heterogenic cell population. We measured fractions of senescence associated β-galactosidase (SA-βgal) positive cells in either mass cultures or colonies of various morphological types (dense, mixed and diffuse) formed by skin fibroblasts from 10 human donors. Although the donors were chosen to be within the same age group (33-54 years), the colony forming efficiency of their fibroblasts (ECO-f) and the percentage of dense, mixed and diffuse colonies varied greatly among the donors. We showed, for the first time, that the SA-βgal positive fraction was the largest in diffuse colonies, confirming that they originated from cells with the least proliferative capacity. The percentage of diffuse colonies was also found to correlate with the SA-βgal positive cells in mass culture. Using Ki67 as a cell proliferation marker, we further demonstrated a strong inverse correlation (r=-0.85, p=0.02) between the percentage of diffuse colonies and the fraction of Ki67+ cells. Moreover, a significant inverse correlation (r=-0.94, p=0.0001) between the percentage of diffuse colonies and ECO-f was found. Our data indicate that quantification of a fraction of diffuse colonies may provide a simple and useful method to evaluate the extent of cellular senescence in human skin fibroblasts.

Past Exposure to Densely Ionizing Radiation Leaves a Unique Permanent Signature in the Genome

PubMed Central

Hande, M. Prakash; Azizova, Tamara V.; Geard, Charles R.; Burak, Ludmilla E.; Mitchell, Catherine R.; Khokhryakov, Valentin F.; Vasilenko, Evgeny K.; Brenner, David J.

2003-01-01

Speculation has long surrounded the question of whether past exposure to ionizing radiation leaves a unique permanent signature in the genome. Intrachromosomal rearrangements or deletions are produced much more efficiently by densely ionizing radiation than by chemical mutagens, x-rays, or endogenous aging processes. Until recently, such stable intrachromosomal aberrations have been very hard to detect, but a new chromosome band painting technique has made their detection practical. We report the detection and quantification of stable intrachromosomal aberrations in lymphocytes of healthy former nuclear-weapons workers who were exposed to plutonium many years ago. Even many years after occupational exposure, more than half the blood cells of the healthy plutonium workers contain large (>6 Mb) intrachromosomal rearrangements. The yield of these aberrations was highly correlated with plutonium dose to the bone marrow. The control groups contained very few such intrachromosomal aberrations. Quantification of this large-scale chromosomal damage in human populations exposed many years earlier will lead to new insights into the mechanisms and risks of cytogenetic damage. PMID:12679897

The need for supplemental breast cancer screening modalities: a perspective of population-based breast cancer screening programs in Japan.

PubMed

Uematsu, Takayoshi

2017-01-01

This article discusses possible supplemental breast cancer screening modalities for younger women with dense breasts from a perspective of population-based breast cancer screening program in Japan. Supplemental breast cancer screening modalities have been proposed to increase the sensitivity and detection rates of early stage breast cancer in women with dense breasts; however, there are no global guidelines that recommend the use of supplemental breast cancer screening modalities in such women. Also, no criterion standard exists for breast density assessment. Based on the current situation of breast imaging in Japan, the possible supplemental breast cancer screening modalities are ultrasonography, digital breast tomosynthesis, and breast magnetic resonance imaging. An appropriate population-based breast cancer screening program based on the balance between cost and benefit should be a high priority. Further research based on evidence-based medicine is encouraged. It is very important that the ethnicity, workforce, workflow, and resources for breast cancer screening in each country should be considered when considering supplemental breast cancer screening modalities for women with dense breasts.

Assessing Woody Vegetation Trends in Sahelian Drylands Using MODIS Based Seasonal Metrics

NASA Technical Reports Server (NTRS)

Brandt, Martin; Hiernaux, Pierre; Rasmussen, Kjeld; Mbow, Cheikh; Kergoat, Laurent; Tagesson, Torbern; Ibrahim, Yahaya Z.; Wele, Abdoulaye; Tucker, Compton J.; Fensholt, Rasmus

2016-01-01

Woody plants play a major role for the resilience of drylands and in peoples' livelihoods. However, due to their scattered distribution, quantifying and monitoring woody cover over space and time is challenging. We develop a phenology driven model and train/validate MODIS (MCD43A4, 500m) derived metrics with 178 ground observations from Niger, Senegal and Mali to estimate woody cover trends from 2000 to 2014 over the entire Sahel. The annual woody cover estimation at 500 m scale is fairly accurate with an RMSE of 4.3 (woody cover %) and r(exp 2) = 0.74. Over the 15 year period we observed an average increase of 1.7 (+/- 5.0) woody cover (%) with large spatial differences: No clear change can be observed in densely populated areas (0.2 +/- 4.2), whereas a positive change is seen in sparsely populated areas (2.1 +/- 5.2). Woody cover is generally stable in cropland areas (0.9 +/- 4.6), reflecting the protective management of parkland trees by the farmers. Positive changes are observed in savannas (2.5 +/- 5.4) and woodland areas (3.9 +/- 7.3). The major pattern of woody cover change reveals strong increases in the sparsely populated Sahel zones of eastern Senegal, western Mali and central Chad, but a decreasing trend is observed in the densely populated western parts of Senegal, northern Nigeria, Sudan and southwestern Niger. This decrease is often local and limited to woodlands, being an indication of ongoing expansion of cultivated areas and selective logging.We show that an overall positive trend is found in areas of low anthropogenic pressure demonstrating the potential of these ecosystems to provide services such as carbon storage, if not over-utilized. Taken together, our results provide an unprecedented synthesis of woody cover dynamics in theSahel, and point to land use and human population density as important drivers, however only partially and locally offsetting a general post-drought increase.

Naturally acquired picornavirus infections in primates at the Dhaka zoo.

PubMed

Oberste, M Steven; Feeroz, Mohammed M; Maher, Kaija; Nix, W Allan; Engel, Gregory A; Begum, Sajeda; Hasan, Kamrul M; Oh, Gunwha; Pallansch, Mark A; Jones-Engel, Lisa

2013-01-01

The conditions in densely populated Bangladesh favor picornavirus transmission, resulting in a high rate of infection in the human population. Data suggest that nonhuman primates (NHP) may play a role in the maintenance and transmission of diverse picornaviruses in Bangladesh. At the Dhaka Zoo, multiple NHP species are caged in close proximity. Their proximity to other species and to humans, both zoo workers and visitors, provides the potential for cross-species transmission. To investigate possible interspecies and intraspecies transmission of picornaviruses among NHP, we collected fecal specimens from nine NHP taxa at the Dhaka Zoo at three time points, August 2007, January 2008, and June 2008. Specimens were screened using real-time PCR for the genera Enterovirus, Parechovirus, and Sapelovirus, and positive samples were typed by VP1 sequencing. Fifty-two picornaviruses comprising 10 distinct serotypes were detected in 83 fecal samples. Four of these serotypes, simian virus 19 (SV19), baboon enterovirus (BaEV), enterovirus 112 (EV112), and EV115, have been solely associated with infection in NHP. EV112, EV115, and SV19 accounted for 88% of all picornaviruses detected. Over 80% of samples from cages housing rhesus macaques, olive baboons, or hamadryas baboons were positive for a picornavirus, while no picornaviruses were detected in samples from capped langurs or vervet monkeys. In contrast to our findings among synanthropic NHP in Bangladesh where 100% of the picornaviruses detected were of human serotypes, in the zoo population, only 15% of picornaviruses detected in NHP were of human origin. Specific serotypes tended to persist over time, suggesting either persistent infection of individuals or cycles of reinfection.

Maternal Dietary Counseling Reduces Consumption of Energy-Dense Foods among Infants: A Randomized Controlled Trial

ERIC Educational Resources Information Center

Vitolo, Marcia Regina; Bortolini, Gisele Ane; Campagnolo, Paula Dal Bo; Hoffman, Daniel J.

2012-01-01

Objective: To evaluate the impact of a dietary counseling in reducing the intake of energy-dense foods by infants. Design: A randomized controlled trial. Setting and Participants: Sao Leopoldo, Brazil. Mothers and infants of a low-income-group population were randomized into intervention (n = 163) and received dietary counseling during 10 home…

Modeling the Dynamic Transmission of Dengue Fever: Investigating Disease Persistence

PubMed Central

Medeiros, Líliam César de Castro; Castilho, César Augusto Rodrigues; Braga, Cynthia; de Souza, Wayner Vieira; Regis, Leda; Monteiro, Antonio Miguel Vieira

2011-01-01

Background Dengue is a disease of great complexity, due to interactions between humans, mosquitoes and various virus serotypes as well as efficient vector survival strategies. Thus, understanding the factors influencing the persistence of the disease has been a challenge for scientists and policy makers. The aim of this study is to investigate the influence of various factors related to humans and vectors in the maintenance of viral transmission during extended periods. Methodology/Principal Findings We developed a stochastic cellular automata model to simulate the spread of dengue fever in a dense community. Each cell can correspond to a built area, and human and mosquito populations are individually monitored during the simulations. Human mobility and renewal, as well as vector infestation, are taken into consideration. To investigate the factors influencing the maintenance of viral circulation, two sets of simulations were performed: (1st) varying human renewal rates and human population sizes and (2nd) varying the house index (fraction of infested buildings) and vector per human ratio. We found that viral transmission is inhibited with the combination of small human populations with low renewal rates. It is also shown that maintenance of viral circulation for extended periods is possible at low values of house index. Based on the results of the model and on a study conducted in the city of Recife, Brazil, which associates vector infestation with Aedes aegytpi egg counts, we question the current methodology used in calculating the house index, based on larval survey. Conclusions/Significance This study contributed to a better understanding of the dynamics of dengue subsistence. Using basic concepts of metapopulations, we concluded that low infestation rates in a few neighborhoods ensure the persistence of dengue in large cities and suggested that better strategies should be implemented to obtain measures of house index values, in order to improve the dengue monitoring and control system. PMID:21264356

Swine vesicular disease in northern Italy: diffusion through densely populated pig areas.

PubMed

Bellini, S; Alborali, L; Zanardi, G; Bonazza, V; Brocchi, E

2010-12-01

At the end of 2006, a recrudescence of swine vesicular disease (SVD) was recorded in Italy and the disease spread widely throughout the northern regions. Lombardy, a densely populated pig area, was most affected and the presence of the disease caused heavy economic losses to the entire pig industry. Although SVD is considered only moderately contagious, the epidemic in the north was characterised by a rapid spread of the condition. Numerous difficulties were encountered in eradicating it. Over the past decade, there has been a significant increase in the population of pigs in Lombardy, concentrated mainly in a few areas which were the most severely affected during the 2006 to 2007 SVD epidemic. Increases in both the pig population and animal movements, combined with weak biosecurity measures, increased the spread rate of the disease and hampered eradication activities.

Brown bear (Ursus arctos) attacks resulting in human casualties in Scandinavia 1977–2016; management implications and recommendations

PubMed Central

Sahlén, Veronica; Arnemo, Jon M.; Sæbø, Solve; Mattsing, Glenn; Kristofferson, Magnus; Brunberg, Sven; Kindberg, Jonas; Swenson, Jon E.

2018-01-01

Human persecution and habitat loss have endangered large carnivore populations worldwide, but some are recovering, exacerbating old conflicts. Carnivores can injure and kill people; the most dramatic form of wildlife-human conflict. In Scandinavia, the brown bear (Ursus arctos) population increased from ~500 bears in 1977 to ~3300 in 2008, with an increase in injuries, fatalities, and public fear of bear attacks. We reviewed media coverage and interviewed victims to explore how bear population trends, hunter education, and other factors may have influenced the number of injuries and fatalities in Scandinavia from 1977 to 2016. We found 42 incidents with 42 injuries and 2 fatalities; 42 were adult men, one was an adult woman conducting forestry work, and one was a boy skiing off-piste. Thirty-three adult men were hunting bears, moose, or small game, often with a hunting dog, and 26 had shot at the bear at 8±11 m before injury. Eleven nonhunters were conducting forestry work, inspecting a hunting area, picking berries, tending livestock, hiking, harassing a denned bear, and one person was killed outside his house at night. Eight of the 11 incidents of nonhunters involved female bears with cubs; three of these family groups were in dens and two were on carcasses. The annual number of hunters injured/killed was mostly influenced by the increase in the bear population size. The pattern was similar regarding injuries/fatalities to other outdoor users, but the relation with the bear population size was weaker than for hunters, and the null model was equally supported. Bear physiology at denning may make encounters with bears more risky in the fall, when bears show prehibernation behavior. Awareness and education efforts, especially among hunters, seem important to ensure human safety. Recreationists and forestry workers should avoid dense vegetation or make noise to warn bears of their presence. PMID:29791471

Emerging Rural Settlement Patterns and the Geographic Redistribution of America's New Immigrants

ERIC Educational Resources Information Center

Lichter, Daniel T.; Johnson, Kenneth M.

2006-01-01

This paper analyzes geographic patterns of population concentration and deconcentration among the foreign-born population during the 1990-2000 period. A goal is to examine whether the foreign-born population, including recent arrivals, are dispersing geographically from metro gateway cities into rural and other less densely populated parts of the…

The Location of Lake Titicaca's Coastal Area During the Tiwanaku and Inca Periods: Methodology and Strategies of Underwater Archaeology

NASA Astrophysics Data System (ADS)

Delaere, Christophe

2017-12-01

For more than 30 years, numerous research projects have revealed the dense and complex human settlement of the lacustrine basin of Lake Titicaca in Bolivia and Peru. Physical evidence of such establishments has been discovered in plains, valleys, and highlands connected to the lake. These remains confirm human occupation and development in this environment, particularly during the Tiwanaku (AD 500-1150) and Inca (AD 1400-1532) Periods. The research project discussed in this paper includes consideration of submerged areas through underwater archaeology. This investigation involves analysis of two areas that have evidence of ancient human occupation but are poorly documented: the coastal and lacustrine regions. Due to its dominance in the landscape, Lake Titicaca has always been a major feature in the life and identity of populations of this vicinity. These inhabitants have developed socio-economic and ritual behaviours directly associated with the lake that have left cultural and material prints that are the foci of the present study.

An automated image processing method for classification of diabetic retinopathy stages from conjunctival microvasculature images

NASA Astrophysics Data System (ADS)

Khansari, Maziyar M.; O'Neill, William; Penn, Richard; Blair, Norman P.; Chau, Felix; Shahidi, Mahnaz

2017-03-01

The conjunctiva is a densely vascularized tissue of the eye that provides an opportunity for imaging of human microcirculation. In the current study, automated fine structure analysis of conjunctival microvasculature images was performed to discriminate stages of diabetic retinopathy (DR). The study population consisted of one group of nondiabetic control subjects (NC) and 3 groups of diabetic subjects, with no clinical DR (NDR), non-proliferative DR (NPDR), or proliferative DR (PDR). Ordinary least square regression and Fisher linear discriminant analyses were performed to automatically discriminate images between group pairs of subjects. Human observers who were masked to the grouping of subjects performed image discrimination between group pairs. Over 80% and 70% of images of subjects with clinical and non-clinical DR were correctly discriminated by the automated method, respectively. The discrimination rates of the automated method were higher than human observers. The fine structure analysis of conjunctival microvasculature images provided discrimination of DR stages and can be potentially useful for DR screening and monitoring.

Genomics, the origins of agriculture, and our changing microbe-scape: time to revisit some old tales and tell some new ones.

PubMed

Harper, Kristin N; Armelagos, George J

2013-12-01

Though agriculture is often viewed as one of humanity's crowning achievements, skeletal evidence indicates that dependence on domesticated plants and animals was accompanied by an increase in infectious disease. Scientists have proposed that many important infections emerged in the period following the advent of agriculture, as a result of newly dense populations and novel proximity to domestic animals that served as reservoirs for novel pathogens. Here, we review genomic evidence regarding pathogen origins, analyzing these data using the epidemiological transition framework. Genetic information has forced us to reconsider how and when many important pathogens emerged; it appears that a number of infections thought to result from contact with domesticated animals arose much earlier than agriculture was adopted. We also consider the broader effect of agriculture upon the microbiome, exploring potential consequences for human health. We end by discussing the changes in the human microbe-scape we are likely to see in the future. Copyright © 2013 Wiley Periodicals, Inc.

Periurban Trypanosoma cruzi–infected Triatoma infestans, Arequipa, Peru

PubMed Central

Bowman, Natalie M.; Kawai, Vivian; Waller, Lance A.; Cornejo del Carpio, Juan Geny; Benzaquen, Eleazar Cordova; Gilman, Robert H.; Bern, Caryn

2006-01-01

In Arequipa, Peru, vectorborne transmission of Chagas disease by Triatoma infestans has become an urban problem. We conducted an entomologic survey in a periurban community of Arequipa to identify risk factors for triatomine infestation and determinants of vector population densities. Of 374 households surveyed, triatomines were collected from 194 (52%), and Trypanosoma cruzi–carrying triatomines were collected from 72 (19.3%). Guinea pig pens were more likely than other animal enclosures to be infested and harbored 2.38× as many triatomines. Stacked brick and adobe enclosures were more likely to have triatomines, while wire mesh enclosures were protected against infestation. In human dwellings, only fully stuccoed rooms were protected against infestation. Spatially, households with triatomines were scattered, while households with T. cruzi–infected triatomines were clustered. Keeping small animals in wire mesh cages could facilitate control of T. infestans in this densely populated urban environment. PMID:17073082

Fine-Scale Map of Encyclopedia of DNA Elements Regions in the Korean Population

PubMed Central

Yoo, Yeon-Kyeong; Ke, Xiayi; Hong, Sungwoo; Jang, Hye-Yoon; Park, Kyunghee; Kim, Sook; Ahn, TaeJin; Lee, Yeun-Du; Song, Okryeol; Rho, Na-Young; Lee, Moon Sue; Lee, Yeon-Su; Kim, Jaeheup; Kim, Young J.; Yang, Jun-Mo; Song, Kyuyoung; Kimm, Kyuchan; Weir, Bruce; Cardon, Lon R.; Lee, Jong-Eun; Hwang, Jung-Joo

2006-01-01

The International HapMap Project aims to generate detailed human genome variation maps by densely genotyping single-nucleotide polymorphisms (SNPs) in CEPH, Chinese, Japanese, and Yoruba samples. This will undoubtedly become an important facility for genetic studies of diseases and complex traits in the four populations. To address how the genetic information contained in such variation maps is transferable to other populations, the Korean government, industries, and academics have launched the Korean HapMap project to genotype high-density Encyclopedia of DNA Elements (ENCODE) regions in 90 Korean individuals. Here we show that the LD pattern, block structure, haplotype diversity, and recombination rate are highly concordant between Korean and the two HapMap Asian samples, particularly Japanese. The availability of information from both Chinese and Japanese samples helps to predict more accurately the possible performance of HapMap markers in Korean disease-gene studies. Tagging SNPs selected from the two HapMap Asian maps, especially the Japanese map, were shown to be very effective for Korean samples. These results demonstrate that the HapMap variation maps are robust in related populations and will serve as an important resource for the studies of the Korean population in particular. PMID:16702437

Area-level risk factors for adverse birth outcomes: trends in urban and rural settings.

PubMed

Kent, Shia T; McClure, Leslie A; Zaitchik, Ben F; Gohlke, Julia M

2013-06-10

Significant and persistent racial and income disparities in birth outcomes exist in the US. The analyses in this manuscript examine whether adverse birth outcome time trends and associations between area-level variables and adverse birth outcomes differ by urban-rural status. Alabama births records were merged with ZIP code-level census measures of race, poverty, and rurality. B-splines were used to determine long-term preterm birth (PTB) and low birth weight (LBW) trends by rurality. Logistic regression models were used to examine differences in the relationships between ZIP code-level percent poverty or percent African-American with either PTB or LBW. Interactions with rurality were examined. Population dense areas had higher adverse birth outcome rates compared to other regions. For LBW, the disparity between population dense and other regions increased during the 1991-2005 time period, and the magnitude of the disparity was maintained through 2010. Overall PTB and LBW rates have decreased since 2006, except within isolated rural regions. The addition of individual-level socioeconomic or race risk factors greatly attenuated these geographical disparities, but isolated rural regions maintained increased odds of adverse birth outcomes. ZIP code-level percent poverty and percent African American both had significant relationships with adverse birth outcomes. Poverty associations remained significant in the most population-dense regions when models were adjusted for individual-level risk factors. Population dense urban areas have heightened rates of adverse birth outcomes. High-poverty African American areas have higher odds of adverse birth outcomes in urban versus rural regions. These results suggest there are urban-specific social or environmental factors increasing risk for adverse birth outcomes in underserved communities. On the other hand, trends in PTBs and LBWs suggest interventions that have decreased adverse birth outcomes elsewhere may not be reaching isolated rural areas.

Heterophysiasis, an intestinal fluke infection of man and vertebrates transmitted by euryhaline gastropods and fish

NASA Astrophysics Data System (ADS)

Taraschewski, H.

1984-03-01

Heterophyes heterophyes, agent of human heterophyiasis in the Near East, is transmitted in marine lagoons and saline inland waters, where the euryhaline intermediate hosts are abundant. In Egypt, mullets, the predominant second intermediate hosts, are customarily consumed raw; thus man becomes infected easily. Symptoms of human infections are usually considered mild. Mullets do not seem to be affected by the metacercariae encysted in the muscles, whereas the growth of the snail host Pirenella conica was found to be enhanced due to the infestation by the trematodes. In laboratory experiments, the flukes were found to be well developed in dogs, foxes and cats, but failed to reach sexual maturity in several other potentially piscivorous mammals and birds. In nature, dogs probably serve as the major reservoir hosts. Heterophyiasis is most prevalent in the Nile Delta, a huge brackish water area which is densely populated by humans and, consequently, also by dogs and cats. In the Far East, besides Heterophyes nocens, several other heterophysids with marine or fresh-water life-cycles are known to infect humans.

Transcriptional and functional profiling defines human small intestinal macrophage subsets.

PubMed

Bujko, Anna; Atlasy, Nader; Landsverk, Ole J B; Richter, Lisa; Yaqub, Sheraz; Horneland, Rune; Øyen, Ole; Aandahl, Einar Martin; Aabakken, Lars; Stunnenberg, Hendrik G; Bækkevold, Espen S; Jahnsen, Frode L

2018-02-05

Macrophages (Mfs) are instrumental in maintaining immune homeostasis in the intestine, yet studies on the origin and heterogeneity of human intestinal Mfs are scarce. Here, we identified four distinct Mf subpopulations in human small intestine (SI). Assessment of their turnover in duodenal transplants revealed that all Mf subsets were completely replaced over time; Mf1 and Mf2, phenotypically similar to peripheral blood monocytes (PBMos), were largely replaced within 3 wk, whereas two subsets with features of mature Mfs, Mf3 and Mf4, exhibited significantly slower replacement. Mf3 and Mf4 localized differently in SI; Mf3 formed a dense network in mucosal lamina propria, whereas Mf4 was enriched in submucosa. Transcriptional analysis showed that all Mf subsets were markedly distinct from PBMos and dendritic cells. Compared with PBMos, Mf subpopulations showed reduced responsiveness to proinflammatory stimuli but were proficient at endocytosis of particulate and soluble material. These data provide a comprehensive analysis of human SI Mf population and suggest a precursor-progeny relationship with PBMos. © 2018 Bujko et al.

A long-term assessment of the variability in winter use of dense conifer cover by female white-tailed deer.

PubMed

Delgiudice, Glenn D; Fieberg, John R; Sampson, Barry A

2013-01-01

Long-term studies allow capture of a wide breadth of environmental variability and a broader context within which to maximize our understanding of relationships to specific aspects of wildlife behavior. The goal of our study was to improve our understanding of the biological value of dense conifer cover to deer on winter range relative to snow depth and ambient temperature. We examined variation among deer in their use of dense conifer cover during a 12-year study period as potentially influenced by winter severity and cover availability. Female deer were fitted with a mixture of very high frequency (VHF, n = 267) and Global Positioning System (GPS, n = 24) collars for monitoring use of specific cover types at the population and individual levels, respectively. We developed habitat composites for four study sites. We fit multinomial response models to VHF (daytime) data to describe population-level use patterns as a function of snow depth, ambient temperature, and cover availability. To develop alternative hypotheses regarding expected spatio-temporal patterns in the use of dense conifer cover, we considered two sets of competing sub-hypotheses. The first set addressed whether or not dense conifer cover was limiting on the four study sites. The second set considered four alternative sub-hypotheses regarding the potential influence of snow depth and ambient temperature on space use patterns. Deer use of dense conifer cover increased the most with increasing snow depth and most abruptly on the two sites where it was most available, suggestive of an energy conservation strategy. Deer use of dense cover decreased the most with decreasing temperatures on the sites where it was most available. At all four sites deer made greater daytime use (55 to >80% probability of use) of open vegetation types at the lowest daily minimum temperatures indicating the importance of thermal benefits afforded from increased exposure to solar radiation. Date-time plots of GPS data (24 hr) allowed us to explore individual diurnal and seasonal patterns of habitat use relative to changes in snow depth. There was significant among-animal variability in their propensity to be found in three density classes of conifer cover and other open types, but little difference between diurnal and nocturnal patterns of habitat use. Consistent with our findings reported elsewhere that snow depth has a greater impact on deer survival than ambient temperature, herein our population-level results highlight the importance of dense conifer cover as snow shelter rather than thermal cover. Collectively, our findings suggest that maximizing availability of dense conifer cover in an energetically beneficial arrangement with quality feeding sites should be a prominent component of habitat management for deer.

A Long-Term Assessment of the Variability in Winter Use of Dense Conifer Cover by Female White-Tailed Deer

PubMed Central

DelGiudice, Glenn D.; Fieberg, John R.; Sampson, Barry A.

2013-01-01

Backgound Long-term studies allow capture of a wide breadth of environmental variability and a broader context within which to maximize our understanding of relationships to specific aspects of wildlife behavior. The goal of our study was to improve our understanding of the biological value of dense conifer cover to deer on winter range relative to snow depth and ambient temperature. Methodology/Principal Findings We examined variation among deer in their use of dense conifer cover during a 12-year study period as potentially influenced by winter severity and cover availability. Female deer were fitted with a mixture of very high frequency (VHF, n = 267) and Global Positioning System (GPS, n = 24) collars for monitoring use of specific cover types at the population and individual levels, respectively. We developed habitat composites for four study sites. We fit multinomial response models to VHF (daytime) data to describe population-level use patterns as a function of snow depth, ambient temperature, and cover availability. To develop alternative hypotheses regarding expected spatio-temporal patterns in the use of dense conifer cover, we considered two sets of competing sub-hypotheses. The first set addressed whether or not dense conifer cover was limiting on the four study sites. The second set considered four alternative sub-hypotheses regarding the potential influence of snow depth and ambient temperature on space use patterns. Deer use of dense conifer cover increased the most with increasing snow depth and most abruptly on the two sites where it was most available, suggestive of an energy conservation strategy. Deer use of dense cover decreased the most with decreasing temperatures on the sites where it was most available. At all four sites deer made greater daytime use (55 to >80% probability of use) of open vegetation types at the lowest daily minimum temperatures indicating the importance of thermal benefits afforded from increased exposure to solar radiation. Date-time plots of GPS data (24 hr) allowed us to explore individual diurnal and seasonal patterns of habitat use relative to changes in snow depth. There was significant among-animal variability in their propensity to be found in three density classes of conifer cover and other open types, but little difference between diurnal and nocturnal patterns of habitat use. Conclusions/Significance Consistent with our findings reported elsewhere that snow depth has a greater impact on deer survival than ambient temperature, herein our population-level results highlight the importance of dense conifer cover as snow shelter rather than thermal cover. Collectively, our findings suggest that maximizing availability of dense conifer cover in an energetically beneficial arrangement with quality feeding sites should be a prominent component of habitat management for deer. PMID:23785421

Strong population genetic structure and larval dispersal capability of the burrowing ghost shrimp (Neotrypaea californiensis)

EPA Science Inventory

The burrowing ghost shrimp, Neotrypaea californiensis, is a vital member of the estuarine benthic community. Dense populations of shrimp are found in the major estuaries of Washington and Oregon. Our study determines the genetic structure of shrimp populations in order to gain ...

Highly Pathogenic Avian Influenza H5N1, Thailand, 2004

PubMed Central

Chaitaweesub, Prasit; Songserm, Thaweesak; Chaisingh, Arunee; Hoonsuwan, Wirongrong; Buranathai, Chantanee; Parakamawongsa, Tippawon; Premashthira, Sith; Amonsin, Alongkorn; Gilbert, Marius; Nielen, Mirjam; Stegeman, Arjan

2005-01-01

In January 2004, highly pathogenic avian influenza (HPAI) virus of the H5N1 subtype was first confirmed in poultry and humans in Thailand. Control measures, e.g., culling poultry flocks, restricting poultry movement, and improving hygiene, were implemented. Poultry populations in 1,417 villages in 60 of 76 provinces were affected in 2004. A total of 83% of infected flocks confirmed by laboratories were backyard chickens (56%) or ducks (27%). Outbreaks were concentrated in the Central, the southern part of the Northern, and Eastern Regions of Thailand, which are wetlands, water reservoirs, and dense poultry areas. More than 62 million birds were either killed by HPAI viruses or culled. H5N1 virus from poultry caused 17 human cases and 12 deaths in Thailand; a number of domestic cats, captive tigers, and leopards also died of the H5N1 virus. In 2005, the epidemic is ongoing in Thailand. PMID:16318716

Rain-fed agriculture thrived despite climate degradation in the pre-Hispanic arid Andes

PubMed Central

Cruz, Pablo; Winkel, Thierry; Ledru, Marie-Pierre; Bernard, Cyril; Egan, Nancy; Swingedouw, Didier; Joffre, Richard

2017-01-01

Archaeological research suggests significant human occupation in the arid Andean highlands during the 13th to 15th centuries, whereas paleoclimatic studies reveal prolonged drier and colder conditions during that period. Which subsistence strategy supported local societies in this harsh environment? Our field and aerial surveys of archaeological dwelling sites, granaries, and croplands provide the first evidence of extended pre-Hispanic agriculture supporting dense human populations in the arid Andes of Bolivia. This unique agricultural system associated with quinoa cultivation was unirrigated, consisting of simple yet extensive landscape modifications. It relied on highly specific environmental knowledge and a set of water-saving practices, including microterracing and biennial fallowing. This intense agricultural activity developed during a period of unfavorable climatic change on a regional and global scale, illustrative of efficient adaptive strategies to cope with this climatic change. PMID:29279865

A 2,000-year reconstruction of the rain-fed maize agricultural niche in the US Southwest.

PubMed

Bocinsky, R Kyle; Kohler, Timothy A

2014-12-04

Humans experience, adapt to and influence climate at local scales. Paleoclimate research, however, tends to focus on continental, hemispheric or global scales, making it difficult for archaeologists and paleoecologists to study local effects. Here we introduce a method for high-frequency, local climate-field reconstruction from tree-rings. We reconstruct the rain-fed maize agricultural niche in two regions of the southwestern United States with dense populations of prehispanic farmers. Niche size and stability are highly variable within and between the regions. Prehispanic rain-fed maize farmers tended to live in agricultural refugia--areas most reliably in the niche. The timing and trajectory of the famous thirteenth century Pueblo migration can be understood in terms of relative niche size and stability. Local reconstructions like these illuminate the spectrum of strategies past humans used to adapt to climate change by recasting climate into the distributions of resources on which they depended.

Sirenian life history

USGS Publications Warehouse

Bonde, Robert K.

2018-01-01

Sirenians, including the manatees and dugongs, are large herbivorous mammals that have evolved to an aquatic form since the Eocene epoch. Sirenians have unique adaptations, including dense bone for ballast and a longitudinal hemidiaphragm separating paired lungs (which aid in maintaining a horizontal posture in the water column), species-specific rostral deflection, and unique dentition for specialized feeding, which all contribute to their success. All sirenians produce one calf per breeding cycle and have long calf-dependency periods. Low reproduction rates are common for long-lived, large mammals, but may compromise their existence in today’s quickly changing world today. All sirenian populations are listed as either threatened or endangered, and some local stocks have been completely extirpated by human activities.

Yellow fever: a reemerging threat.

PubMed

Gardner, Christina L; Ryman, Kate D

2010-03-01

Yellow fever (YF) is a viral disease, endemic to tropical regions of Africa and the Americas, which principally affects humans and nonhuman primates and is transmitted via the bite of infected mosquitoes. Yellow fever virus (YFV) can cause devastating epidemics of potentially fatal, hemorrhagic disease. Despite mass vaccination campaigns to prevent and control these outbreaks, the risk of major YF epidemics, especially in densely populated, poor urban settings, both in Africa and South America, has greatly increased. Consequently, YF is considered an emerging, or reemerging disease of considerable importance. This article comprehensively reviews the history, microbiology, epidemiology, clinical presentation, diagnosis, and treatment of YFV, as well as the vaccines produced to combat YF. 2010 Elsevier Inc. All rights reserved.

Louisiana's Coastal Crisis: Characterizing Household and Community-Level Impacts and Responses

NASA Astrophysics Data System (ADS)

Austin, D. E.

2017-12-01

Rich in natural resources and critical ecosystems, the Mississippi delta also is the site of numerous human communities, from sparsely populated towns to dense urban neighborhoods. People who live and work within the delta face major challenges as they confront land loss, subsidence, and storms. This presentation outlines key household and community-level impacts of these environmental changes and both individual and collective responses to them. Based on two decades of applied ethnographic research in the region, as well as the author's participation as an advisor to federal, state, and local organizations, the presentation considers historical and contemporary processes and practices, social organization, and cultural dynamics to analyze proposed policies for addressing the impacts.

A case study of potential human health impacts from petroleum coke transfer facilities.

PubMed

Dourson, Michael L; Chinkin, Lyle R; MacIntosh, David L; Finn, Jennifer A; Brown, Kathleen W; Reid, Stephen B; Martinez, Jeanelle M

2016-11-01

Petroleum coke or "petcoke" is a solid material created during petroleum refinement and is distributed via transfer facilities that may be located in densely populated areas. The health impacts from petcoke exposure to residents living in proximity to such facilities were evaluated for a petcoke transfer facilities located in Chicago, Illinois. Site-specific, margin of safety (MOS) and margin of exposure (MOE) analyses were conducted using estimated airborne and dermal exposures. The exposure assessment was based on a combined measurement and modeling program that included multiyear on-site air monitoring, air dispersion modeling, and analyses of soil and surfaces in residential areas adjacent to two petcoke transfer facilities located in industrial areas. Airborne particulate matter less than 10 microns (PM 10 ) were used as a marker for petcoke. Based on daily fence line monitoring, the average daily PM 10 concentration at the KCBX Terminals measured on-site was 32 μg/m 3 , with 89% of 24-hr average PM 10 concentrations below 50 μg/m 3 and 99% below 100 μg/m 3 . A dispersion model estimated that the emission sources at the KCBX Terminals produced peak PM 10 levels attributed to the petcoke facility at the most highly impacted residence of 11 μg/m 3 on an annual average basis and 54 μg/m 3 on 24-hr average basis. Chemical indicators of petcoke in soil and surface samples collected from residential neighborhoods adjacent to the facilities were equivalent to levels in corresponding samples collected at reference locations elsewhere in Chicago, a finding that is consistent with limited potential for off-site exposure indicated by the fence line monitoring and air dispersion modeling. The MOE based upon dispersion model estimates ranged from 800 to 900 for potential inhalation, the primary route of concern for particulate matter. This indicates a low likelihood of adverse health effects in the surrounding community. Implications: Handling of petroleum coke at bulk material transfer facilities has been identified as a concern for the public health of surrounding populations. The current assessment, based on measurements and modeling of two facilities located in a densely populated urban area, indicates that petcoke transport and accumulation in off-site locations is minimal. In addition, estimated human exposures, if any, are well below levels that could be anticipated to produce adverse health effects in the general population.

Three-Step Buildup of the 17 March 2015 Storm Ring Current: Implication for the Cause of the Unexpected Storm Intensification

NASA Astrophysics Data System (ADS)

Keika, Kunihiro; Seki, Kanako; Nosé, Masahito; Miyoshi, Yoshizumi; Lanzerotti, Louis J.; Mitchell, Donald G.; Gkioulidou, Matina; Manweiler, Jerry W.

2018-01-01

We examine the spatiotemporal variations of the energy density and the energy spectral evolution of energetic ions in the inner magnetosphere during the main phase of the 17 March 2015 storm, using data from the RBSPICE and EMFISIS instruments onboard Van Allen Probes. The storm developed in response to two southward IMF intervals separated by about 3 h. In contrast to two steps seen in the Dst/SYM-H index, the ring current ion population evolved in three steps: the first subphase was apparently caused by the earlier southward IMF, and the subsequent subphases occurred during the later southward IMF period. Ion energy ranges that contribute to the ring current differed between the three subphases. We suggest that the spectral evolution resulted from the penetration of different plasma sheet populations. The ring current buildup during the first subphase was caused by the penetration of a relatively low-energy population that had existed in the plasma sheet during a prolonged prestorm northward IMF interval. The deeper penetration of the lower-energy population was responsible for the second subphase. The third subphase, where the storm was unexpectedly intensified to a Dst/SYM-H level of <-200 nT, was caused by the penetration of a hot, dense plasma sheet population. We attribute the hot, dense population to the entry of hot, dense solar wind into the plasma sheet and/or ion heating/acceleration in the near-Earth plasma sheet associated with magnetotail activity such as reconnection and dipolarization.

Five anthropogenic factors that will radically alter forest conditions and management needs in the Northern United States

Treesearch

Stephen R. Shifley; W. Keith Moser; David J. Nowak; Patrick D. Miles; Brett J. Butler; Francisco X. Aguilar; Ryan D. DeSantis; Eric J. Greenfield

2014-01-01

The Northern United States includes the 20 states bounded by Maine, Maryland, Missouri, and Minnesota. With 70 million ha of forestland and 124 million people, it is the most densely forested (42% of land area) and most densely populated (74 people/km2) quadrant of the United States. Three recent, large-scale, multiresource assessments of forest...

Land development, land use, and urban sprawl in Puerto Rico integrating remote sensing and population census data.

Treesearch

Sebastian Martinuzzi; William A. Gould; Olga M. Ramos Gonzalez

2007-01-01

The island of Puerto Rico has both a high population density and a long history of ineffective land use planning. This study integrates geospatial technology and population census data to understand how people use and develop the lands. We define three new regions for Puerto Rico: Urban (16%), Densely Populated Rural (36%), and Sparsely Populated Rural (48%). Eleven...

Temperature and humidity based projections of a rapid rise in global heat stress exposure during the 21st century

NASA Astrophysics Data System (ADS)

Coffel, Ethan D.; Horton, Radley M.; de Sherbinin, Alex

2018-01-01

As a result of global increases in both temperature and specific humidity, heat stress is projected to intensify throughout the 21st century. Some of the regions most susceptible to dangerous heat and humidity combinations are also among the most densely populated. Consequently, there is the potential for widespread exposure to wet bulb temperatures that approach and in some cases exceed postulated theoretical limits of human tolerance by mid- to late-century. We project that by 2080 the relative frequency of present-day extreme wet bulb temperature events could rise by a factor of 100-250 (approximately double the frequency change projected for temperature alone) in the tropics and parts of the mid-latitudes, areas which are projected to contain approximately half the world’s population. In addition, population exposure to wet bulb temperatures that exceed recent deadly heat waves may increase by a factor of five to ten, with 150-750 million person-days of exposure to wet bulb temperatures above those seen in today’s most severe heat waves by 2070-2080. Under RCP 8.5, exposure to wet bulb temperatures above 35 °C—the theoretical limit for human tolerance—could exceed a million person-days per year by 2080. Limiting emissions to follow RCP 4.5 entirely eliminates exposure to that extreme threshold. Some of the most affected regions, especially Northeast India and coastal West Africa, currently have scarce cooling infrastructure, relatively low adaptive capacity, and rapidly growing populations. In the coming decades heat stress may prove to be one of the most widely experienced and directly dangerous aspects of climate change, posing a severe threat to human health, energy infrastructure, and outdoor activities ranging from agricultural production to military training.

Population density and suicide in Scotland.

PubMed

Stark, Cameron; Hopkins, Paddy; Gibbs, Diane; Belbin, Alan; Hay, Alistair

2007-01-01

Suicide rates among men have increased in Scotland while falling in neighbouring countries. A national suicide prevention strategy has been produced. Previous work found that some rural areas of Scotland had higher than average rates of male suicide and undetermined deaths. This article describes the association between population density and suicide and undetermined death rates in Scotland. Anonymised information on deaths from suicide and undetermined cause in Scotland were obtained from the General Registrar Office for 1981-1999, including information on postcode sector. Each postcode sector was assigned a deprivation and population density score. Loglinear models were used to examine the effects of time period (grouped into four periods), deprivation quintiles, population density (grouped into four categories) and their interactions in each sex in three age groups. A significance level of 5% was used throughout. Adjusted rate ratios and 95% confidence intervals were based on models that included only significant factors and interactions. In men, there were higher rate ratios in the most densely populated and least densely populated quartiles, with intermediate rate ratios in other areas. There was no association with population density in women aged less than 25 years, a similar pattern to men in 25-44 year old women, and lower rates in rural areas in older women. Higher levels of deprivation were associated with higher rate ratios of suicide in both sexes and all age groups. Rate ratios over time increased in younger men and women, remained stable in older men, and declined in older women. Deprivation is associated with higher rates of suicide and undetermined deaths at all levels of population density and in all age groups. The highest rates of suicide among men are in the most and least densely populated areas, after adjusting for deprivation. The effect is different among women, with no effect among younger women, and lower rates among older women in areas with lower population density.

Naturally Acquired Picornavirus Infections in Primates at the Dhaka Zoo

PubMed Central

Feeroz, Mohammed M.; Maher, Kaija; Nix, W. Allan; Engel, Gregory A.; Begum, Sajeda; Hasan, Kamrul M.; Oh, Gunwha; Pallansch, Mark A.; Jones-Engel, Lisa

2013-01-01

The conditions in densely populated Bangladesh favor picornavirus transmission, resulting in a high rate of infection in the human population. Data suggest that nonhuman primates (NHP) may play a role in the maintenance and transmission of diverse picornaviruses in Bangladesh. At the Dhaka Zoo, multiple NHP species are caged in close proximity. Their proximity to other species and to humans, both zoo workers and visitors, provides the potential for cross-species transmission. To investigate possible interspecies and intraspecies transmission of picornaviruses among NHP, we collected fecal specimens from nine NHP taxa at the Dhaka Zoo at three time points, August 2007, January 2008, and June 2008. Specimens were screened using real-time PCR for the genera Enterovirus, Parechovirus, and Sapelovirus, and positive samples were typed by VP1 sequencing. Fifty-two picornaviruses comprising 10 distinct serotypes were detected in 83 fecal samples. Four of these serotypes, simian virus 19 (SV19), baboon enterovirus (BaEV), enterovirus 112 (EV112), and EV115, have been solely associated with infection in NHP. EV112, EV115, and SV19 accounted for 88% of all picornaviruses detected. Over 80% of samples from cages housing rhesus macaques, olive baboons, or hamadryas baboons were positive for a picornavirus, while no picornaviruses were detected in samples from capped langurs or vervet monkeys. In contrast to our findings among synanthropic NHP in Bangladesh where 100% of the picornaviruses detected were of human serotypes, in the zoo population, only 15% of picornaviruses detected in NHP were of human origin. Specific serotypes tended to persist over time, suggesting either persistent infection of individuals or cycles of reinfection. PMID:23097447

Feeding the microbiota-gut-brain axis: diet, microbiome, and neuropsychiatry.

PubMed

Sandhu, Kiran V; Sherwin, Eoin; Schellekens, Harriët; Stanton, Catherine; Dinan, Timothy G; Cryan, John F

2017-01-01

The microbial population residing within the human gut represents one of the most densely populated microbial niche in the human body with growing evidence showing it playing a key role in the regulation of behavior and brain function. The bidirectional communication between the gut microbiota and the brain, the microbiota-gut-brain axis, occurs through various pathways including the vagus nerve, the immune system, neuroendocrine pathways, and bacteria-derived metabolites. This axis has been shown to influence neurotransmission and the behavior that are often associated with neuropsychiatric conditions. Therefore, research targeting the modulation of this gut microbiota as a novel therapy for the treatment of various neuropsychiatric conditions is gaining interest. Numerous factors have been highlighted to influence gut microbiota composition, including genetics, health status, mode of birth, and environment. However, it is diet composition and nutritional status that has repeatedly been shown to be one of the most critical modifiable factors regulating the gut microbiota at different time points across the lifespan and under various health conditions. Thus the microbiota is poised to play a key role in nutritional interventions for maintaining brain health. Copyright © 2016 Elsevier Inc. All rights reserved.

Landscape Archeology: Remote Sensing Investigation of the Ancient Maya in the Peten Rainforest of Northern Guatemala

NASA Technical Reports Server (NTRS)

Sever, Thomas L.; Irwin, Daniel E.; Arnold, James E. (Technical Monitor)

2002-01-01

Through the use of airborne and satellite imagery we are improving our ability to investigate ancient Maya settlement, subsistence, and landscape modification in this dense forest region. Today the area is threatened by encroaching settlement and deforestation. However, it was in this region that the Maya civilization began, flourished, and abruptly disappeared for unknown reasons in the 9th century AD. At the time of their collapse they had attained one of the highest population densities in human history. How the Maya were able to successfully manage water and feed this dense population is not well understood at this time. A NASA-funded project used remote sensing technology to investigate large seasonal swamps (bajos) that make up 40 percent of the landscape. Through the use of remote sensing, ancient Maya features such as sites, roadways, canals and water reservoirs have been detected and verified through ground reconnaissance. The results of this preliminary research cast new light on the adaptation of the ancient Maya to their environment. Microenvironmental variation within the wetlands was elucidated and the different vegetation associations identified in the satellite imagery. More than 70 new archeological sites within and at the edges of the bajo were mapped and tested. Modification of the landscape by the Maya in the form of dams and reservoirs in the Holmul River and its tributaries and possible drainage canals in bajos was demonstrated. The use of Landsat Thematic Mapper (TM) and Enhanced Thematic Mapper (ETM), one-meter IKONOS satellite imagery, as well as high resolution airborne STAR-3i radar imagery--2.5 meter backscatter/10 meter Digital Elevation Model (DEM)--are opening new possibilities for understanding how a civilization was able to survive for centuries upon a karat topographic landscape. This understanding is critical for the current population that is currently experiencing rapid population growth and destroying the landscape through nontraditional farming and grazing techniques, resulting in socioeconomic problems.

The seaweed fly (Coelopidae) can facilitate environmental survival and transmission of E. coli O157 at sandy beaches.

PubMed

Swinscoe, Isobel; Oliver, David M; Gilburn, Andre S; Quilliam, Richard S

2018-06-19

The sustainable management of recreational beaches is essential for minimising risk of human exposure to microbial pathogens whilst simultaneously maintaining valuable ecosystem services. Decaying seaweed on public beaches is gaining recognition as a substrate for microbial contamination, and is a potentially significant reservoir for human pathogens in close proximity to beach users. Closely associated with beds of decaying seaweed are dense populations of the seaweed fly (Coelopidae), which could influence the spatio-temporal fate of seaweed-associated human pathogens within beach environments. Replicated mesocosms containing seaweed inoculated with a bioluminescent strain of the zoonotic pathogen E. coli O157:H7, were used to determine the effects of two seaweed flies, Coelopa frigida and C. pilipes, on E. coli O157:H7 survival dynamics. Multiple generations of seaweed flies and their larvae significantly enhanced persistence of E. coli O157:H7 in simulated wrack habitats, demonstrating that both female and male C. frigida flies are capable of transferring E. coli O157:H7 between individual wrack beds and into the sand. Adult fly faeces can contain significant concentrations of E. coli O157:H7, which suggests they are capable of acting as biological vectors and bridge hosts between wrack habitats and other seaweed fly populations, and facilitate the persistence and dispersal of E. coli O157:H7 in sandy beach environments. This study provides the first evidence that seaweed fly populations inhabiting natural wrack beds contaminated with the human pathogen E. coli O157:H7 have the capacity to amplify the hazard source, and therefore potential transmission risk, to beach users exposed to seaweed and sand in the intertidal zone. The risk to public health from seaweed flies and decaying wrack beds is usually limited by human avoidance behaviour; however, seaweed fly migration and nuisance inland plagues in urban areas could increase human exposure routes beyond the beach environment. Copyright © 2018 Elsevier Ltd. All rights reserved.

Nicergoline inhibits human platelet Ca2+ signalling through triggering a microtubule‐dependent reorganization of the platelet ultrastructure

PubMed Central

Walford, T; Musa, F I

2015-01-01

Background and Purpose Recently, we demonstrated that a pericellular Ca2+ recycling system potentiates agonist‐evoked Ca2+ signalling and granule secretion in human platelets and hypothesized a role for the membrane complex (MC) in orchestrating the accumulation of Ca2+ in the pericellular region. Previous work has demonstrated that treatment with high concentrations of nicergoline may disrupt the MC through an ability to trigger a re‐organization of the dense tubular system. Experiments were therefore performed to assess whether nicergoline‐induced changes in platelet ultrastructure affects thrombin‐evoked Ca2+ fluxes and dense granule secretion. Experimental Approach Thrombin‐evoked Ca2+ fluxes were monitored in Fura‐2‐ or Fluo‐5N‐loaded human platelets, or using platelet suspensions containing Fluo‐4 or Rhod‐5N K+ salts. Fluorescence microscopy was utilized to monitor microtubule structure and intracellular Ca2+ store distribution in TubulinTracker‐ and Fluo‐5N‐loaded platelets respectively. Dense granule secretion was monitored using luciferin–luciferase. Key Results Nicergoline treatment inhibited thrombin‐evoked Ca2+ signalling and induced alterations in the microtubule structure and the distribution of intracellular Ca2+ stores in platelets. Nicergoline altered the generation and spreading of thrombin‐induced pericellular Ca2+ signals and almost completely prevented dense granule secretion. Stabilization of microtubules using taxol reversed most effects of nicergoline on platelet Ca2+ signalling and partially reversed its effects on dense granule secretion. Conclusions and Implications Nicergoline‐induced alterations to platelet ultrastructure disrupt platelet Ca2+ signalling in a manner that would be predicted if the MC had been disrupted. These data suggest that nicergoline may be a useful prototype for the discovery of novel MC‐disrupting anti‐thrombotics. PMID:26450366

Nicergoline inhibits human platelet Ca(2+) signalling through triggering a microtubule-dependent reorganization of the platelet ultrastructure.

PubMed

Walford, T; Musa, F I; Harper, A G S

2016-01-01

Recently, we demonstrated that a pericellular Ca(2+) recycling system potentiates agonist-evoked Ca(2+) signalling and granule secretion in human platelets and hypothesized a role for the membrane complex (MC) in orchestrating the accumulation of Ca(2+) in the pericellular region. Previous work has demonstrated that treatment with high concentrations of nicergoline may disrupt the MC through an ability to trigger a re-organization of the dense tubular system. Experiments were therefore performed to assess whether nicergoline-induced changes in platelet ultrastructure affects thrombin-evoked Ca(2+) fluxes and dense granule secretion. Thrombin-evoked Ca(2+) fluxes were monitored in Fura-2- or Fluo-5N-loaded human platelets, or using platelet suspensions containing Fluo-4 or Rhod-5N K(+) salts. Fluorescence microscopy was utilized to monitor microtubule structure and intracellular Ca(2+) store distribution in TubulinTracker- and Fluo-5N-loaded platelets respectively. Dense granule secretion was monitored using luciferin-luciferase. Nicergoline treatment inhibited thrombin-evoked Ca(2+) signalling and induced alterations in the microtubule structure and the distribution of intracellular Ca(2+) stores in platelets. Nicergoline altered the generation and spreading of thrombin-induced pericellular Ca(2+) signals and almost completely prevented dense granule secretion. Stabilization of microtubules using taxol reversed most effects of nicergoline on platelet Ca(2+) signalling and partially reversed its effects on dense granule secretion. Nicergoline-induced alterations to platelet ultrastructure disrupt platelet Ca(2+) signalling in a manner that would be predicted if the MC had been disrupted. These data suggest that nicergoline may be a useful prototype for the discovery of novel MC-disrupting anti-thrombotics. © 2015 The British Pharmacological Society.

Fabrication, Properties and Applications of Dense Hydroxyapatite: A Review

PubMed Central

Prakasam, Mythili; Locs, Janis; Salma-Ancane, Kristine; Loca, Dagnija; Largeteau, Alain; Berzina-Cimdina, Liga

2015-01-01

In the last five decades, there have been vast advances in the field of biomaterials, including ceramics, glasses, glass-ceramics and metal alloys. Dense and porous ceramics have been widely used for various biomedical applications. Current applications of bioceramics include bone grafts, spinal fusion, bone repairs, bone fillers, maxillofacial reconstruction, etc. Amongst the various calcium phosphate compositions, hydroxyapatite, which has a composition similar to human bone, has attracted wide interest. Much emphasis is given to tissue engineering, both in porous and dense ceramic forms. The current review focusses on the various applications of dense hydroxyapatite and other dense biomaterials on the aspects of transparency and the mechanical and electrical behavior. Prospective future applications, established along the aforesaid applications of hydroxyapatite, appear to be promising regarding bone bonding, advanced medical treatment methods, improvement of the mechanical strength of artificial bone grafts and better in vitro/in vivo methodologies to afford more particular outcomes. PMID:26703750

Increased frequency of spontaneous neoplastic transformation in progeny of bystander cells from cultures exposed to densely ionizing radiation.

PubMed

Buonanno, Manuela; de Toledo, Sonia M; Azzam, Edouard I

2011-01-01

An increased risk of carcinogenesis caused by exposure to space radiation during prolonged space travel is a limiting factor for human space exploration. Typically, astronauts are exposed to low fluences of ionizing particles that target only a few cells in a tissue at any one time. The propagation of stressful effects from irradiated to neighboring bystander cells and their transmission to progeny cells would be of importance in estimates of the health risks of exposure to space radiation. With relevance to the risk of carcinogenesis, we investigated, in model C3H 10T½ mouse embryo fibroblasts (MEFs), modulation of the spontaneous frequency of neoplastic transformation in the progeny of bystander MEFs that had been in co-culture 10 population doublings earlier with MEFs exposed to moderate doses of densely ionizing iron ions (1 GeV/nucleon) or sparsely ionizing protons (1 GeV). An increase (P<0.05) in neoplastic transformation frequency, likely mediated by intercellular communication through gap junctions, was observed in the progeny of bystander cells that had been in co-culture with cells irradiated with iron ions, but not with protons.

Enabling the sustainable Faecal Sludge Management service delivery chain-A case study of dense settlements in Kigali, Rwanda.

PubMed

Akumuntu, Jean Baptiste; Wehn, Uta; Mulenga, Martin; Brdjanovic, Damir

2017-08-01

The lack of access to basic sanitation is a global concern and alarmingly prevalent in low- and middle- income countries. In the densely populated settlements of these countries, on-site sanitation systems are usually the only feasible option because dwellers there have no sewers in place to connect to. Using on-site sanitation facilities results in an accumulation of faecal sludge which needs to be properly managed to ensure the well-being of the users as well as the surrounding environment. Unfortunately, often the conditions for faecal sludge management (FSM) within dense settlements are adverse and thus hamper sustainable FSM. We use the normative framework of the FSM enabling environment to gather empirical evidence from densely populated settlements of Kigali city in Rwanda to examine current FSM practices and the extent to which these are being influenced and affected by the setting within which they are taking place. The analysis of the study findings confirms that the existing conditions for FSM in these settlements are inadequate. The specific constraints that hinder the achievement of sustainable FSM include limited government focus on the sanitation sector, high turnover of staff in relevant government institutions, pit sludge management is not placed on the sanitation projects agenda, the existing relevant bylaws are not pro-poor oriented, a lack of clear responsibilities, a lack of relevant local professional training opportunities, unaffordability of FSM services and an inhibition to discuss FSM. Drawing on the involved stakeholders' own perceptions and suggestions, we identify possible approaches to overcome the identified constraints and to allow all actors in the FSM chain to contribute effectively to the management of faecal sludge in densely populated low-income urban settlements. Finally, our study also presents a contribution to the theoretical conceptualisation of the enabling environment for sustainable FSM. Copyright © 2017 Elsevier GmbH. All rights reserved.

Alcohol and Drug Use, Abuse, and Dependence in Urban Areas and Colonias of the Texas-Mexico Border

ERIC Educational Resources Information Center

Wallisch, Lynn S.; Spence, Richard T.

2006-01-01

This study describes the prevalence of alcohol and drug use, abuse, and dependence among adults on the Texas-Mexico border in 2002-2003. The findings are based on survey responses from a random sample of 1,200 adults living in households in three communities: El Paso, a densely populated city in west Texas; the less dense urbanized areas of the…

Development of the Policy Indicator Checklist: A Tool to Identify and Measure Policies for Calorie-Dense Foods and Sugar-Sweetened Beverages Across Multiple Settings

PubMed Central

Hallett, Allen M.; Parker, Nathan; Kudia, Ousswa; Kao, Dennis; Modelska, Maria; Rifai, Hanadi; O’Connor, Daniel P.

2015-01-01

Objectives. We developed the policy indicator checklist (PIC) to identify and measure policies for calorie-dense foods and sugar-sweetened beverages to determine how policies are clustered across multiple settings. Methods. In 2012 and 2013 we used existing literature, policy documents, government recommendations, and instruments to identify key policies. We then developed the PIC to examine the policy environments across 3 settings (communities, schools, and early care and education centers) in 8 communities participating in the Childhood Obesity Research Demonstration Project. Results. Principal components analysis revealed 5 components related to calorie-dense food policies and 4 components related to sugar-sweetened beverage policies. Communities with higher youth and racial/ethnic minority populations tended to have fewer and weaker policy environments concerning calorie-dense foods and healthy foods and beverages. Conclusions. The PIC was a helpful tool to identify policies that promote healthy food environments across multiple settings and to measure and compare the overall policy environments across communities. There is need for improved coordination across settings, particularly in areas with greater concentration of youths and racial/ethnic minority populations. Policies to support healthy eating are not equally distributed across communities, and disparities continue to exist in nutrition policies. PMID:25790397

Development of the policy indicator checklist: a tool to identify and measure policies for calorie-dense foods and sugar-sweetened beverages across multiple settings.

PubMed

Lee, Rebecca E; Hallett, Allen M; Parker, Nathan; Kudia, Ousswa; Kao, Dennis; Modelska, Maria; Rifai, Hanadi; O'Connor, Daniel P

2015-05-01

We developed the policy indicator checklist (PIC) to identify and measure policies for calorie-dense foods and sugar-sweetened beverages to determine how policies are clustered across multiple settings. In 2012 and 2013 we used existing literature, policy documents, government recommendations, and instruments to identify key policies. We then developed the PIC to examine the policy environments across 3 settings (communities, schools, and early care and education centers) in 8 communities participating in the Childhood Obesity Research Demonstration Project. Principal components analysis revealed 5 components related to calorie-dense food policies and 4 components related to sugar-sweetened beverage policies. Communities with higher youth and racial/ethnic minority populations tended to have fewer and weaker policy environments concerning calorie-dense foods and healthy foods and beverages. The PIC was a helpful tool to identify policies that promote healthy food environments across multiple settings and to measure and compare the overall policy environments across communities. There is need for improved coordination across settings, particularly in areas with greater concentration of youths and racial/ethnic minority populations. Policies to support healthy eating are not equally distributed across communities, and disparities continue to exist in nutrition policies.

Multi-objective route planning for dangerous goods using compromise programming

NASA Astrophysics Data System (ADS)

Li, Rongrong; Leung, Yee

2011-09-01

The transportation of dangerous goods (DG) can significantly affect the human and natural environment if accidents occur during the transportation process. Hong Kong is a large city with high population density and narrow streets. Due to the land constraints, vehicles carrying DG inevitably have to pass through densely populated areas or their vicinities. Therefore, safe DG transportation is of paramount importance. There is thus an urgent need to review and improve the way trucks carrying DG are being routed on the road networks. Routing of such vehicles should consider not only the operating cost, but also the safety of travelers in the network, the population potentially exposed, and the possible damage inflicted to the surrounding properties and facilities in the event of a DG incident. This research develops a novel methodology for the determination of optimal routes for DG transportation under conflicting objectives by means of the compromise programming approach. With the support of geographical information system (GIS), a case study is carried out for the transportation of DG in the road network of Hong Kong. The experimental results confirm the effectiveness of the proposed approach.

Africa: continent of genome contrasts with implications for biomedical research and health.

PubMed

Ramsay, Michèle

2012-08-31

The genomic architecture of African populations is poorly understood and there is considerable variation between ethno-linguistic groups. Genome-wide approaches have been extensively applied to search for genetic associations to complex traits in Europeans, but rarely in Africans. This is largely attributed to lower levels of funding, poor infrastructure and public health systems, and to the small pool of trained scientists. High levels of genetic variation and underlying population structure in Africans present significant challenges, but lower levels of linkage disequilibrium provide an opportunity for more effective localisation of causal variants. High throughput technologies, including dense genotyping arrays, genome sequencing and epigenome studies, together with plummeting costs, are making research more affordable, even for African scientists. Understanding the interactions between genome structure and environmental influences is essential to interpreting their contributions to the increase in infectious diseases and non-communicable diseases, exacerbated by adverse environments and lifestyle choices. The unique genome dynamics in African populations have an important role to play in understanding human health and susceptibility to disease. Copyright © 2012. Published by Elsevier B.V.

Neotropical coastal lagoons: an appraisal of their biodiversity, functioning, threats and conservation management.

PubMed

Esteves, F A; Caliman, A; Santangelo, J M; Guariento, R D; Farjalla, V F; Bozelli, R L

2008-11-01

Neotropical coastal lagoons (NCL) are human-dominated ecosystems. Their distribution along densely populated coastal areas of developing countries makes these systems among the most threatened in the world. Here, we summarize some aspects of the causes and consequences of NCL biodiversity, their functioning, their importance to the surrounding populations, their fragility, and their responses to local and global anthropogenic impacts and the challenges that Neotropical countries face in conserving these systems. Although still scarce and geographically concentrated, a growing body of studies has shown that NCLs are physiographically diversified systems, which harbor a considerable and particular proportion of the Neotropical inland aquatic biodiversity. Despite the fact that coastal lagoons are ecotones that are intricately connected to surrounding environments, they develop mechanisms for structural and functional regulation, which confer to these systems higher productivity and carrying capacities than surrounding ecosystems. Such traits attract residential developments and subsidize local traditional populations with important economic and aesthetic ecosystem revenues such as fisheries and scenic beauty. However, the disorganized human occupation around NCLs are causing profound impacts such as eutrophication, salinization, exotic species introduction, as well as other effects, which are ultimately imposing major habitat degradations and biodiversity extirpations in NCLs. We argue that interdisciplinary conservation strategies, which integrate scientific expertise, government officials, private companies and the general public, are the most likely to overcome the geographic and economic obstacles to NCL conservation.

A comparative study of the structural organization of spheres derived from the adult human subventricular zone and glioblastoma biopsies

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

Vik-Mo, Einar Osland, E-mail: e.o.vik-mo@medisin.uio.no; Department of Neurosurgery, Oslo University Hospital, Oslo; Sandberg, Cecilie

2011-04-15

Sphere forming assays have been useful to enrich for stem like cells in a range of tumors. The robustness of this system contrasts the difficulties in defining a stem cell population based on cell surface markers. We have undertaken a study to describe the cellular and organizational composition of tumorspheres, directly comparing these to neurospheres derived from the adult human subventricular zone (SVZ). Primary cell cultures from brain tumors were found to contain variable fractions of cells positive for tumor stem cell markers (CD133 (2-93%)/SSEA1 (3-15%)/CXCR4 (1-72%)). All cultures produced tumors upon xenografting. Tumorspheres contained a heterogeneous population of cells,more » but were structurally organized with stem cell markers present at the core of spheres, with markers of more mature glial progenitors and astrocytes at more peripheral location. Ultrastructural studies showed that tumorspheres contained a higher fraction of electron dense cells in the core than the periphery (36% and 19%, respectively). Neurospheres also contained a heterogeneous cell population, but did not have an organization similar to tumorspheres. Although tumorspheres clearly display irregular and neoplastic cells, they establish an organized structure with an outward gradient of differentiation. We suggest that this organization is central in maintaining the tumor stem cell pool.« less

Prevalence of External Injuries in Small Cetaceans in Aruban Waters, Southern Caribbean

PubMed Central

Luksenburg, Jolanda A.

2014-01-01

Aruba, located close to the coasts of Colombia and Venezuela, is one of the most densely populated islands in the Caribbean and supports a wide range of marine-related socio-economic activities. However, little is known about the impacts of human activities on the marine environment. Injuries in marine mammals can be used to examine interactions with human activities and identify potential threats to the survival of populations. The prevalence of external injuries and tooth rake marks were examined in Atlantic spotted dolphin (Stenella frontalis) (n = 179), bottlenose dolphin (Tursiops truncatus) (n = 76) and false killer whale (Pseudorca crassidens) (n = 71) in Aruban waters using photo identification techniques. Eleven injury categories were defined and linked to either human-related activities or natural causes. All injury categories were observed. In total, 18.7% of all individuals had at least one injury. Almost half (41.7%) of the injuries could be attributed to human interactions, of which fishing gear was the most common cause (53.3%) followed by propeller hits (13.3%). Major disfigurements were observed in all three species and could be attributed to interactions with fishing gear. The results of this study indicate that fishing gear and propeller hits may pose threats to small and medium-sized cetaceans in Aruban waters. Thus, long-term monitoring of population trends is warranted. Shark-inflicted bite wounds were observed in Atlantic spotted dolphin and bottlenose dolphin. Bite wounds of cookie cutter sharks (Isistius sp.) were recorded in all three species, and include the first documented record of a cookie cutter shark bite in Atlantic spotted dolphin. This is one of the few studies which investigates the prevalence of injuries in cetaceans in the Caribbean. Further study is necessary to determine to which extent the injuries observed in Aruba affect the health and survival of local populations. PMID:24586473

Differences in mammographic density between Asian and Caucasian populations: a comparative analysis.

PubMed

Rajaram, Nadia; Mariapun, Shivaani; Eriksson, Mikael; Tapia, Jose; Kwan, Pui Yoke; Ho, Weang Kee; Harun, Faizah; Rahmat, Kartini; Czene, Kamila; Taib, Nur Aishah Mohd; Hall, Per; Teo, Soo Hwang

2017-01-01

Mammographic density is a measurable and modifiable biomarker that is strongly and independently associated with breast cancer risk. Paradoxically, although Asian women have lower risk of breast cancer, studies of minority Asian women in predominantly Caucasian populations have found that Asian women have higher percent density. In this cross-sectional study, we compared the distribution of mammographic density for a matched cohort of Asian women from Malaysia and Caucasian women from Sweden, and determined if variations in mammographic density could be attributed to population differences in breast cancer risk factors. Volumetric mammographic density was compared for 1501 Malaysian and 4501 Swedish healthy women, matched on age and body mass index. We used multivariable log-linear regression to determine the risk factors associated with mammographic density and mediation analysis to identify factors that account for differences in mammographic density between the two cohorts. Compared to Caucasian women, percent density was 2.0% higher among Asian women (p < 0.001), and dense volume was 5.7 cm 3 higher among pre-menopausal Asian women (p < 0.001). Dense volume was 3.0 cm 3 lower among post-menopausal Asian women (p = 0.009) compared to post-menopausal Caucasian women, and this difference was attributed to population differences in height, weight, and parity (p < 0.001). Our analysis suggests that among post-menopausal women, population differences in mammographic density and risk to breast cancer may be accounted for by height, weight, and parity. Given that pre-menopausal Asian and Caucasian women have similar population risk to breast cancer but different dense volume, development of more appropriate biomarkers of risk in pre-menopausal women is required.

Population exposure to hazardous air quality due to the 2015 fires in Equatorial Asia.

PubMed

Crippa, P; Castruccio, S; Archer-Nicholls, S; Lebron, G B; Kuwata, M; Thota, A; Sumin, S; Butt, E; Wiedinmyer, C; Spracklen, D V

2016-11-16

Vegetation and peatland fires cause poor air quality and thousands of premature deaths across densely populated regions in Equatorial Asia. Strong El-Niño and positive Indian Ocean Dipole conditions are associated with an increase in the frequency and intensity of wildfires in Indonesia and Borneo, enhancing population exposure to hazardous concentrations of smoke and air pollutants. Here we investigate the impact on air quality and population exposure of wildfires in Equatorial Asia during Fall 2015, which were the largest over the past two decades. We performed high-resolution simulations using the Weather Research and Forecasting model with Chemistry based on a new fire emission product. The model captures the spatio-temporal variability of extreme pollution episodes relative to space- and ground-based observations and allows for identification of pollution sources and transport over Equatorial Asia. We calculate that high particulate matter concentrations from fires during Fall 2015 were responsible for persistent exposure of 69 million people to unhealthy air quality conditions. Short-term exposure to this pollution may have caused 11,880 (6,153-17,270) excess mortalities. Results from this research provide decision-relevant information to policy makers regarding the impact of land use changes and human driven deforestation on fire frequency and population exposure to degraded air quality.

Population exposure to hazardous air quality due to the 2015 fires in Equatorial Asia

PubMed Central

Crippa, P.; Castruccio, S.; Archer-Nicholls, S.; Lebron, G. B.; Kuwata, M.; Thota, A.; Sumin, S.; Butt, E.; Wiedinmyer, C.; Spracklen, D. V.

2016-01-01

Vegetation and peatland fires cause poor air quality and thousands of premature deaths across densely populated regions in Equatorial Asia. Strong El-Niño and positive Indian Ocean Dipole conditions are associated with an increase in the frequency and intensity of wildfires in Indonesia and Borneo, enhancing population exposure to hazardous concentrations of smoke and air pollutants. Here we investigate the impact on air quality and population exposure of wildfires in Equatorial Asia during Fall 2015, which were the largest over the past two decades. We performed high-resolution simulations using the Weather Research and Forecasting model with Chemistry based on a new fire emission product. The model captures the spatio-temporal variability of extreme pollution episodes relative to space- and ground-based observations and allows for identification of pollution sources and transport over Equatorial Asia. We calculate that high particulate matter concentrations from fires during Fall 2015 were responsible for persistent exposure of 69 million people to unhealthy air quality conditions. Short-term exposure to this pollution may have caused 11,880 (6,153–17,270) excess mortalities. Results from this research provide decision-relevant information to policy makers regarding the impact of land use changes and human driven deforestation on fire frequency and population exposure to degraded air quality. PMID:27848989

Intraspecific competition and high food availability are associated with insular gigantism in a lizard.

PubMed

Pafilis, Panayiotis; Meiri, Shai; Foufopoulos, Johannes; Valakos, Efstratios

2009-09-01

Resource availability, competition, and predation commonly drive body size evolution. We assess the impact of high food availability and the consequent increased intraspecific competition, as expressed by tail injuries and cannibalism, on body size in Skyros wall lizards (Podarcis gaigeae). Lizard populations on islets surrounding Skyros (Aegean Sea) all have fewer predators and competitors than on Skyros but differ in the numbers of nesting seabirds. We predicted the following: (1) the presence of breeding seabirds (providing nutrients) will increase lizard population densities; (2) dense lizard populations will experience stronger intraspecific competition; and (3) such aggression, will be associated with larger average body size. We found a positive correlation between seabird and lizard densities. Cannibalism and tail injuries were considerably higher in dense populations. Increases in cannibalism and tail loss were associated with large body sizes. Adult cannibalism on juveniles may select for rapid growth, fuelled by high food abundance, setting thus the stage for the evolution of gigantism.

Development of human nervous tissue upon differentiation of embryonic stem cells in three-dimensional culture.

PubMed

Preynat-Seauve, Olivier; Suter, David M; Tirefort, Diderik; Turchi, Laurent; Virolle, Thierry; Chneiweiss, Herve; Foti, Michelangelo; Lobrinus, Johannes-Alexander; Stoppini, Luc; Feki, Anis; Dubois-Dauphin, Michel; Krause, Karl Heinz

2009-03-01

Researches on neural differentiation using embryonic stem cells (ESC) require analysis of neurogenesis in conditions mimicking physiological cellular interactions as closely as possible. In this study, we report an air-liquid interface-based culture of human ESC. This culture system allows three-dimensional cell expansion and neural differentiation in the absence of added growth factors. Over a 3-month period, a macroscopically visible, compact tissue developed. Histological coloration revealed a dense neural-like neural tissue including immature tubular structures. Electron microscopy, immunochemistry, and electrophysiological recordings demonstrated a dense network of neurons, astrocytes, and oligodendrocytes able to propagate signals. Within this tissue, tubular structures were niches of cells resembling germinal layers of human fetal brain. Indeed, the tissue contained abundant proliferating cells expressing markers of neural progenitors. Finally, the capacity to generate neural tissues on air-liquid interface differed for different ESC lines, confirming variations of their neurogenic potential. In conclusion, this study demonstrates in vitro engineering of a human neural-like tissue with an organization that bears resemblance to early developing brain. As opposed to previously described methods, this differentiation (a) allows three-dimensional organization, (b) yields dense interconnected neural tissue with structurally and functionally distinct areas, and (c) is spontaneously guided by endogenous developmental cues.

Widespread anthropogenic Gd anomalies in waters. Preliminary results on a small Mediterranean drainage basin (Thau Lagoon, France)

NASA Astrophysics Data System (ADS)

ELBAZ-POULICHET, F.; SEIDEL, J.

2001-05-01

Recent evidence of perturbation of REE signature marked by pronounced positive Gd anomalies have been found in surface waters of densely populated and industrialised regions, in Germany and Japan. This study presents REE data in water from a small Mediterranean basin (the Thau lagoon) located on the southwestern French Mediterranean coast, which is a densely populated region.. Positive Gd anomalies (up to 5) are observed in the major river feeding the lagoon and in the lagoon where the highest values are encountered in the close vicinity of the continental sources. The systematic and concomitant observation of similar anomalies, in sewage treatment plant effluents, suggests that they have an anthropogenic origin. The suspended load does not display any Gd anomaly indicating that the Gd input occurs mainly in the dissolved phase. In addition, the appearance of Gd anomaly is not accompanied by an overall increase of REE concentrations. The gadopentetic acid, Gd(DTPA)2- used as a contrasting agent in magnetic resonance imaging could account for such anomalies but remains to be confirmed. Finally positive Gd anomalies appear a common feature in waters of densely populated regions with high standard of living . These anomalies may have an application in water resource management as a tracer of anthropogenic impacts.

Crowdsourcing urban air temperatures from smartphone battery temperatures

NASA Astrophysics Data System (ADS)

Overeem, A.; Robinson, J. C. R.; Leijnse, H.; Steeneveld, G. J.; Horn, B. K. P.; Uijlenhoet, R.

2013-08-01

Accurate air temperature observations in urban areas are important for meteorology and energy demand planning. They are indispensable to study the urban heat island effect and the adverse effects of high temperatures on human health. However, the availability of temperature observations in cities is often limited. Here we show that relatively accurate air temperature information for the urban canopy layer can be obtained from an alternative, nowadays omnipresent source: smartphones. In this study, battery temperatures were collected by an Android application for smartphones. A straightforward heat transfer model is employed to estimate daily mean air temperatures from smartphone battery temperatures for eight major cities around the world. The results demonstrate the enormous potential of this crowdsourcing application for real-time temperature monitoring in densely populated areas.

Real-time detection of moving objects from moving vehicles using dense stereo and optical flow

NASA Technical Reports Server (NTRS)

Talukder, Ashit; Matthies, Larry

2004-01-01

Dynamic scene perception is very important for autonomous vehicles operating around other moving vehicles and humans. Most work on real-time object tracking from moving platforms has used sparse features or assumed flat scene structures. We have recently extended a real-time, dense stereo system to include realtime, dense optical flow, enabling more comprehensive dynamic scene analysis. We describe algorithms to robustly estimate 6-DOF robot egomotion in the presence of moving objects using dense flow and dense stereo. We then use dense stereo and egomotion estimates to identify & other moving objects while the robot itself is moving. We present results showing accurate egomotion estimation and detection of moving people and vehicles under general 6-DOF motion of the robot and independently moving objects. The system runs at 18.3 Hz on a 1.4 GHz Pentium M laptop, computing 160x120 disparity maps and optical flow fields, egomotion, and moving object segmentation. We believe this is a significant step toward general unconstrained dynamic scene analysis for mobile robots, as well as for improved position estimation where GPS is unavailable.

Real-time detection of moving objects from moving vehicles using dense stereo and optical flow

NASA Technical Reports Server (NTRS)

Talukder, Ashit; Matthies, Larry

2004-01-01

Dynamic scene perception is very important for autonomous vehicles operating around other moving vehicles and humans. Most work on real-time object tracking from moving platforms has used sparse features or assumed flat scene structures. We have recently extended a real-time, dense stereo system to include real-time, dense optical flow, enabling more comprehensive dynamic scene analysis. We describe algorithms to robustly estimate 6-DOF robot egomotion in the presence of moving objects using dense flow and dense stereo. We then use dense stereo and egomotion estimates to identity other moving objects while the robot itself is moving. We present results showing accurate egomotion estimation and detection of moving people and vehicles under general 6-DOF motion of the robot and independently moving objects. The system runs at 18.3 Hz on a 1.4 GHz Pentium M laptop, computing 160x120 disparity maps and optical flow fields, egomotion, and moving object segmentation. We believe this is a significant step toward general unconstrained dynamic scene analysis for mobile robots, as well as for improved position estimation where GPS is unavailable.

Real-time Detection of Moving Objects from Moving Vehicles Using Dense Stereo and Optical Flow

NASA Technical Reports Server (NTRS)

Talukder, Ashit; Matthies, Larry

2004-01-01

Dynamic scene perception is very important for autonomous vehicles operating around other moving vehicles and humans. Most work on real-time object tracking from moving platforms has used sparse features or assumed flat scene structures. We have recently extended a real-time. dense stereo system to include realtime. dense optical flow, enabling more comprehensive dynamic scene analysis. We describe algorithms to robustly estimate 6-DOF robot egomotion in the presence of moving objects using dense flow and dense stereo. We then use dense stereo and egomotion estimates to identify other moving objects while the robot itself is moving. We present results showing accurate egomotion estimation and detection of moving people and vehicles under general 6DOF motion of the robot and independently moving objects. The system runs at 18.3 Hz on a 1.4 GHz Pentium M laptop. computing 160x120 disparity maps and optical flow fields, egomotion, and moving object segmentation. We believe this is a significant step toward general unconstrained dynamic scene analysis for mobile robots, as well as for improved position estimation where GPS is unavailable.

Mutation in a primate-conserved retrotransposon reveals a noncoding RNA as a mediator of infantile encephalopathy

PubMed Central

Cartault, François; Munier, Patrick; Benko, Edgar; Desguerre, Isabelle; Hanein, Sylvain; Boddaert, Nathalie; Bandiera, Simonetta; Vellayoudom, Jeanine; Krejbich-Trotot, Pascale; Bintner, Marc; Hoarau, Jean-Jacques; Girard, Muriel; Génin, Emmanuelle; de Lonlay, Pascale; Fourmaintraux, Alain; Naville, Magali; Rodriguez, Diana; Feingold, Josué; Renouil, Michel; Munnich, Arnold; Westhof, Eric; Fähling, Michael; Lyonnet, Stanislas; Henrion-Caude, Alexandra

2012-01-01

The human genome is densely populated with transposons and transposon-like repetitive elements. Although the impact of these transposons and elements on human genome evolution is recognized, the significance of subtle variations in their sequence remains mostly unexplored. Here we report homozygosity mapping of an infantile neurodegenerative disease locus in a genetic isolate. Complete DNA sequencing of the 400-kb linkage locus revealed a point mutation in a primate-specific retrotransposon that was transcribed as part of a unique noncoding RNA, which was expressed in the brain. In vitro knockdown of this RNA increased neuronal apoptosis, consistent with the inappropriate dosage of this RNA in vivo and with the phenotype. Moreover, structural analysis of the sequence revealed a small RNA-like hairpin that was consistent with the putative gain of a functional site when mutated. We show here that a mutation in a unique transposable element-containing RNA is associated with lethal encephalopathy, and we suggest that RNAs that harbor evolutionarily recent repetitive elements may play important roles in human brain development. PMID:22411793

Area-level risk factors for adverse birth outcomes: trends in urban and rural settings

PubMed Central

2013-01-01

Background Significant and persistent racial and income disparities in birth outcomes exist in the US. The analyses in this manuscript examine whether adverse birth outcome time trends and associations between area-level variables and adverse birth outcomes differ by urban–rural status. Methods Alabama births records were merged with ZIP code-level census measures of race, poverty, and rurality. B-splines were used to determine long-term preterm birth (PTB) and low birth weight (LBW) trends by rurality. Logistic regression models were used to examine differences in the relationships between ZIP code-level percent poverty or percent African-American with either PTB or LBW. Interactions with rurality were examined. Results Population dense areas had higher adverse birth outcome rates compared to other regions. For LBW, the disparity between population dense and other regions increased during the 1991–2005 time period, and the magnitude of the disparity was maintained through 2010. Overall PTB and LBW rates have decreased since 2006, except within isolated rural regions. The addition of individual-level socioeconomic or race risk factors greatly attenuated these geographical disparities, but isolated rural regions maintained increased odds of adverse birth outcomes. ZIP code-level percent poverty and percent African American both had significant relationships with adverse birth outcomes. Poverty associations remained significant in the most population-dense regions when models were adjusted for individual-level risk factors. Conclusions Population dense urban areas have heightened rates of adverse birth outcomes. High-poverty African American areas have higher odds of adverse birth outcomes in urban versus rural regions. These results suggest there are urban-specific social or environmental factors increasing risk for adverse birth outcomes in underserved communities. On the other hand, trends in PTBs and LBWs suggest interventions that have decreased adverse birth outcomes elsewhere may not be reaching isolated rural areas. PMID:23759062

Flea (Siphonaptera) species richness in the Great Basin Desert and island biogeography theory.

PubMed

Bossard, Robert L

2014-06-01

Numbers of flea (Siphonaptera) species (flea species richness) on individual mammals should be higher on large mammals, mammals with dense populations, and mammals with large geographic ranges, if mammals are islands for fleas. I tested the first two predictions with regressions of H. J. Egoscue's trapping data on flea species richness collected from individual mammals against mammal size and population density from the literature. Mammal size and population density did not correlate with flea species richness. Mammal geographic range did, in earlier studies. The intermediate-sized (31 g), moderately dense (0.004 individuals/m(2)) Peromyscus truei (Shufeldt) had the highest richness with eight flea species on one individual. Overall, island biogeography theory does not describe the distribution of flea species on mammals in the Great Basin Desert, based on H. J. Egoscue's collections. Alternatively, epidemiological or metapopulation theories may explain flea species richness. © 2014 The Society for Vector Ecology.

Population Change Within Nonmetropolitan and Metropolitan Areas: Lessons from New York State.

ERIC Educational Resources Information Center

Moore, Dan E.

According to the results of an in-depth study of the process of population change in New York State, the less densely settled an area, the more likely it is to grow in the 1970's. This is more evidence of the recent major U.S. demographic phenomenon of a revival of population growth in non-metropolitan areas. Population data for the sixty-two…

Current status of practical applications: Probiotics in dairy cattle

USDA-ARS?s Scientific Manuscript database

The gastrointestinal microbial population of dairy cattle is dense and diverse, and can be utilized to reduce pathogenic bacterial populations as well as improve animal productivity and environmental impacts. Because of the nature of the dairy industry, probiotic products have been widely used to e...

Overpopulation: Where Malthus Went Wrong.

ERIC Educational Resources Information Center

Morton, John S.; Shaw, Jane S.; Stroup, Richard L.

1997-01-01

Reviews the theories of 18th-century social scientist Thomas Malthus regarding population and his predictions of massive worldwide famine. Maintains that countries with a tradition of private property rights can sustain a dense population and food supply. Examines the relationship between low birth rate and economic prosperity. (MJP)

Sewage contamination of a densely populated coral 'atoll' (Bermuda).

PubMed

Jones, Ross; Parsons, Rachel; Watkinson, Elaine; Kendell, David

2011-08-01

Bermuda is a densely populated coral 'atoll' located on a seamount in the mid-Atlantic (Sargasso Sea). There is no national sewerage system and the ∼20 × 10(6) L of sewage generated daily is disposed of via marine outfalls, cess pits/septic tanks underneath houses and through waste disposal (injection) wells. Gastrointestinal (GI) enterococci concentrations were measured in surface seawater samples collected monthly at multiple locations across the island over a 5-year period. According to the EU Bathing Water Directive microbial classification categories, 18 of the sites were in the 'excellent' category, four sites in the 'good', five sites were in the 'sufficient' and three sites in the 'poor' categories. One of the sites in the 'poor' category is beside a popular swimming beach. Between 20-30% of 58 sub tidal sediment samples collected from creeks, coves, bays, harbours and marinas in the Great Sound complex on the western side of Bermuda tested positive for the presence of the human specific bacterial biomarker Bacteroides (using culture-independent PCR-based methods) and for the faecal biomarker coprostanol (5β-cholestan-3-β-ol, which ranged in concentration from <0.05-0.77 mg kg( - 1). There was a significant statistical correlation between these two independent techniques for faecal contamination identification. Overall the microbial water quality and sedimentary biomarker surveys suggest sewage contamination in Bermuda was quite low compared with other published studies; nevertheless, several sewage contamination hotpots exist, and these could be attributed to discharge of raw sewage from house boats, from nearby sewage outfalls and leakage from septic tanks/cess pits.

Modeling 3D Facial Shape from DNA

PubMed Central

Claes, Peter; Liberton, Denise K.; Daniels, Katleen; Rosana, Kerri Matthes; Quillen, Ellen E.; Pearson, Laurel N.; McEvoy, Brian; Bauchet, Marc; Zaidi, Arslan A.; Yao, Wei; Tang, Hua; Barsh, Gregory S.; Absher, Devin M.; Puts, David A.; Rocha, Jorge; Beleza, Sandra; Pereira, Rinaldo W.; Baynam, Gareth; Suetens, Paul; Vandermeulen, Dirk; Wagner, Jennifer K.; Boster, James S.; Shriver, Mark D.

2014-01-01

Human facial diversity is substantial, complex, and largely scientifically unexplained. We used spatially dense quasi-landmarks to measure face shape in population samples with mixed West African and European ancestry from three locations (United States, Brazil, and Cape Verde). Using bootstrapped response-based imputation modeling (BRIM), we uncover the relationships between facial variation and the effects of sex, genomic ancestry, and a subset of craniofacial candidate genes. The facial effects of these variables are summarized as response-based imputed predictor (RIP) variables, which are validated using self-reported sex, genomic ancestry, and observer-based facial ratings (femininity and proportional ancestry) and judgments (sex and population group). By jointly modeling sex, genomic ancestry, and genotype, the independent effects of particular alleles on facial features can be uncovered. Results on a set of 20 genes showing significant effects on facial features provide support for this approach as a novel means to identify genes affecting normal-range facial features and for approximating the appearance of a face from genetic markers. PMID:24651127

Urban and rural land use in Puerto Rico

Treesearch

Sebastian Martinuzzi; William A. Gould; Olga M. Ramos Gonzalez; Maya Quinones; Michael E. Jimenez

2008-01-01

We have developed three land use regions for Puerto Rico: Urban, Suburban, and Rural (Gould et al. 2008; Martinuzzi et al. 2007). These three regions can also be considered urban, densely-populated rural, and sparsely-populated rural or as urban and wildland with a wildland-urban interface. The suburban use is the most dynamic in terms of population growth and land...

Toxoplasma gondii: Biochemical and biophysical characterization of recombinant soluble dense granule proteins GRA2 and GRA6

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

Bittame, Amina; Université Grenoble Alpes, 38042 Grenoble; Effantin, Grégory

2015-03-27

The most prominent structural feature of the parasitophorous vacuole (PV) in which the intracellular parasite Toxoplasma gondii proliferates is a membranous nanotubular network (MNN), which interconnects the parasites and the PV membrane. The MNN function remains unclear. The GRA2 and GRA6 proteins secreted from the parasite dense granules into the PV have been implicated in the MNN biogenesis. Amphipathic alpha-helices (AAHs) predicted in GRA2 and an alpha-helical hydrophobic domain predicted in GRA6 have been proposed to be responsible for their membrane association, thereby potentially molding the MMN in its structure. Here we report an analysis of the recombinant proteins (expressedmore » in detergent-free conditions) by circular dichroism, which showed that full length GRA2 displays an alpha-helical secondary structure while recombinant GRA6 and GRA2 truncated of its AAHs are mainly random coiled. Dynamic light scattering and transmission electron microscopy showed that recombinant GRA6 and truncated GRA2 constitute a homogenous population of small particles (6–8 nm in diameter) while recombinant GRA2 corresponds to 2 populations of particles (∼8–15 nm and up to 40 nm in diameter, respectively). The unusual properties of GRA2 due to its AAHs are discussed. - Highlights: • Toxoplasma gondii: soluble GRA2 forms 2 populations of particles. • T. gondii: the dense granule protein GRA2 folds intrinsically as an alpha-helix. • T. gondii: monomeric soluble GRA6 forms particles of 6–8 nm in diameter. • T. gondii: monomeric soluble GRA6 is random coiled. • Unusual biophysical properties of the dense granule protein GRA2 from T. gondii.« less

How Dense!

ERIC Educational Resources Information Center

Codner, A. C.

1985-01-01

Suggests examining population density to help students understand density as a chemical concept. Simple experiments and demonstrations with carbon dioxide, burning oil, natural gas, and temperature are also suggested. (DH)

Dynamics and distribution of black abalone populations at San Nicolas Island

USGS Publications Warehouse

VanBlaricom, Glenn R.; Hochberg, F.G.

1993-01-01

Dense populations of black abalones (Haliotis cracherodii Leach) were monitored in permanent intertidal plots at nine sites on San Nicolas Island from 1981 through 1990. Densities were essentially constant at all four sites along the north shore of the island throughout the study period. Densities at five sites along the south shore were more variable, possibly reflecting asynchronous variation in recruitment, mortality resulting from wave disturbance, and removal by people. Temporal variation of abalone densities apparently was not influenced by sea otters or abalone withering syndrome during this study. Abalones were strongly aggregated in space. Highest densities occurred in areas of irregular substrata, apparently as a result of preference for crevices and vertical faces. The locations of dense patches were persistent in time.

Key techniques and risk management for the application of the Pile-Beam-Arch (PBA) excavation method: a case study of the Zhongjie subway station.

PubMed

Guan, Yong-ping; Zhao, Wen; Li, Shen-gang; Zhang, Guo-bin

2014-01-01

The design and construction of shallow-buried tunnels in densely populated urban areas involve many challenges. The ground movements induced by tunneling effects pose potential risks to infrastructure such as surface buildings, pipelines, and roads. In this paper, a case study of the Zhongjie subway station located in Shenyang, China, is examined to investigate the key construction techniques and the influence of the Pile-Beam-Arch (PBA) excavation method on the surrounding environment. This case study discusses the primary risk factors affecting the environmental safety and summarizes the corresponding risk mitigation measures and key techniques for subway station construction using the PBA excavation method in a densely populated urban area.

77 FR 45869 - Endangered and Threatened Wildlife and Plants; Listing the British Columbia Distinct Population...

Federal Register 2010, 2011, 2012, 2013, 2014

2012-08-01

... (Service) received a petition from eight conservation groups and two individuals to list the Queen... dense second-growth stands that may support populations of some prey species, but research across North... preliminary research results released openly at interagency meetings, but have characterized these as...

Controlling Japanese barberry: Alternative methods and impact on tick populations

Treesearch

Jeffrey S. Ward; Scott C. Williams; Thomas E. Worthley

2011-01-01

Japanese barberry (Berberis thunbergii) is classified as invasive in 20 states and four Canadian provinces. It is also established in another 11 states. In addition to forming dense thickets that can inhibit forest regeneration and native herbaceous plant populations, barberry understories can harbor greatly enhanced levels of blacklegged ticks (

Brief communication: Hair density and body mass in mammals and the evolution of human hairlessness.

PubMed

Sandel, Aaron A

2013-09-01

Humans are unusual among mammals in appearing hairless. Several hypotheses propose explanations for this phenotype, but few data are available to test these hypotheses. To elucidate the evolutionary history of human "hairlessness," a comparative approach is needed. One previous study on primate hair density concluded that great apes have systematically less dense hair than smaller primates. While there is a negative correlation between body size and hair density, it remains unclear whether great apes have less dense hair than is expected for their body size. To revisit the scaling relationship between hair density and body size in mammals, I compiled data from the literature on 23 primates and 29 nonprimate mammals and conducted Phylogenetic Generalized Least Squares regressions. Among anthropoids, there is a significant negative correlation between hair density and body mass. Chimpanzees display the largest residuals, exhibiting less dense hair than is expected for their body size. There is a negative correlation between hair density and body mass among the broader mammalian sample, although the functional significance of this scaling relationship remains to be tested. Results indicate that all primates, and chimpanzees in particular, are relatively hairless compared to other mammals. This suggests that there may have been selective pressures acting on the ancestor of humans and chimpanzees that led to an initial reduction in hair density. To further understand the evolution of human hairlessness, a systematic study of hair density and physiology in a wide range of species is necessary. Copyright © 2013 Wiley Periodicals, Inc.

Primate energy input and the evolutionary transition to energy-dense diets in humans.

PubMed

Simmen, Bruno; Pasquet, Patrick; Masi, Shelly; Koppert, Georgius J A; Wells, Jonathan C K; Hladik, Claude Marcel

2017-06-14

Humans and other large-brained hominins have been proposed to increase energy turnover during their evolutionary history. Such increased energy turnover is plausible, given the evolution of energy-rich diets, but requires empirical confirmation. Framing human energetics in a phylogenetic context, our meta-analysis of 17 wild non-human primate species shows that daily metabolizable energy input follows an allometric relationship with body mass where the allometric exponent for mass is 0.75 ± 0.04, close to that reported for daily energy expenditure measured with doubly labelled water in primates. Human populations at subsistence level ( n = 6) largely fall within the variation of primate species in the scaling of energy intake and therefore do not consume significantly more energy than predicted for a non-human primate of equivalent mass. By contrast, humans ingest a conspicuously lower mass of food (-64 ± 6%) compared with primates and maintain their energy intake relatively more constantly across the year. We conclude that our hominin hunter-gatherer ancestors did not increase their energy turnover beyond the allometric relationship characterizing all primate species. The reduction in digestive costs due to consumption of a lower mass of high-quality food, as well as stabilization of energy supply, may have been important evolutionary steps enabling encephalization in the absence of significantly raised energy intakes. © 2017 The Author(s).

VizieR Online Data Catalog: Structure of young stellar clusters. II. (Kuhn+, 2015)

NASA Astrophysics Data System (ADS)

Kuhn, M. A.; Getman, K. V.; Feigelson, E. D.

2015-07-01

We investigate the intrinsic stellar populations (estimated total numbers of OB and pre-main-sequence stars down to 0.1Mȯ) that are present in 17 massive star-forming regions (MSFRs) surveyed by the MYStIX project. The study is based on the catalog of >31000 MYStIX Probable Complex Members with both disk-bearing and disk-free populations, compensating for extinction, nebulosity, and crowding effects. Correction for observational sensitivities is made using the X-ray luminosity function and the near-infrared initial mass function --a correction that is often not made by infrared surveys of young stars. The resulting maps of the projected structure of the young stellar populations, in units of intrinsic stellar surface density, allow direct comparison between different regions. Several regions have multiple dense clumps, similar in size and density to the Orion Nebula Cluster. The highest projected density of ~34000 stars/pc2 is found in the core of the RCW 38 cluster. Histograms of surface density show different ranges of values in different regions, supporting the conclusion of Bressert et al. (B10; 2010MNRAS.409L..54B) that no universal surface-density threshold can distinguish between clustered and distributed star formation. However, a large component of the young stellar population of MSFRs resides in dense environments of 200-10000 stars/pc2 (including within the nearby Orion molecular clouds), and we find that there is no evidence for the B10 conclusion that such dense regions form an extreme "tail" of the distribution. Tables of intrinsic populations for these regions are used in our companion study of young cluster properties and evolution. (3 data files).

Extra-metabolic energy use and the rise in human hyper-density

NASA Astrophysics Data System (ADS)

Burger, Joseph R.; Weinberger, Vanessa P.; Marquet, Pablo A.

2017-03-01

Humans, like all organisms, are subject to fundamental biophysical laws. Van Valen predicted that, because of zero-sum dynamics, all populations of all species in a given environment flux the same amount of energy on average. Damuth’s ’energetic equivalence rule’ supported Van Valen´s conjecture by showing a tradeoff between few big animals per area with high individual metabolic rates compared to abundant small species with low energy requirements. We use metabolic scaling theory to compare variation in densities and individual energy use in human societies to other land mammals. We show that hunter-gatherers occurred at densities lower than the average for a mammal of our size. Most modern humans, in contrast, concentrate in large cities at densities up to four orders of magnitude greater than hunter-gatherers, yet consume up to two orders of magnitude more energy per capita. Today, cities across the globe flux greater energy than net primary productivity on a per area basis. This is possible by importing enormous amounts of energy and materials required to sustain hyper-dense, modern humans. The metabolic rift with nature created by modern cities fueled largely by fossil energy poses formidable challenges for establishing a sustainable relationship on a rapidly urbanizing, yet finite planet.

Extra-metabolic energy use and the rise in human hyper-density.

PubMed

Burger, Joseph R; Weinberger, Vanessa P; Marquet, Pablo A

2017-03-02

Humans, like all organisms, are subject to fundamental biophysical laws. Van Valen predicted that, because of zero-sum dynamics, all populations of all species in a given environment flux the same amount of energy on average. Damuth's 'energetic equivalence rule' supported Van Valen´s conjecture by showing a tradeoff between few big animals per area with high individual metabolic rates compared to abundant small species with low energy requirements. We use metabolic scaling theory to compare variation in densities and individual energy use in human societies to other land mammals. We show that hunter-gatherers occurred at densities lower than the average for a mammal of our size. Most modern humans, in contrast, concentrate in large cities at densities up to four orders of magnitude greater than hunter-gatherers, yet consume up to two orders of magnitude more energy per capita. Today, cities across the globe flux greater energy than net primary productivity on a per area basis. This is possible by importing enormous amounts of energy and materials required to sustain hyper-dense, modern humans. The metabolic rift with nature created by modern cities fueled largely by fossil energy poses formidable challenges for establishing a sustainable relationship on a rapidly urbanizing, yet finite planet.

AN ELECTRON MICROSCOPE STUDY OF NERVES INFECTED WITH HUMAN POLIOMYELITIS VIRUS

PubMed Central

De Robertis, E.; Schmitt, F. O

1949-01-01

Sciatic nerves of rhesus monkeys infected with CAM and Wis. '45 strains of human poliomyelitis virus were fixed in formalin, sectioned, fragmented, and examined in the electron microscope. Most of the neurotubules of nerves infected with the CAM strain have normal appearance but a very small number show the presence of dense particles irregularly aligned within the edges of the neurotubules. The diameters of the particles range between 160 and 500 Å, the mean being 330 Å. The particles were found in regions along the nerve which varied with the time after infection, indicating a central movement of the morphological alteration of the order of 2 mm. per hour. Relatively abundant dense particulate material was found in nerves infected with Wis. '45 strain virus and the particles were chiefly attached to the edges of the neurotubules and in the adjacent areas of the field. The dense particles appear to be associated with the virus infection but no further characterization is possible at this time. PMID:18140661

Summer ammonia measurements in a densely populated Mediterranean city

NASA Astrophysics Data System (ADS)

Pandolfi, M.; Amato, F.; Reche, C.; Alastuey, A.; Otjes, R. P.; Blom, M. J.; Querol, X.

2012-08-01

Real-time measurements of ambient concentrations of gas-phase ammonia (NH3) were performed in Barcelona (NE Spain) in summer between May and September 2011. Two measurement sites were selected: one in an urban background traffic-influenced area (UB) and the other in the historical city centre (CC). Levels of NH3 were higher at CC (5.6 ± 2.1 μg m-3 or 7.5 ± 2.8 ppbv) compared with UB (2.2 ± 1.0 μg m-3 or 2.9 ± 1.3 ppbv). This difference is attributed to the contribution from non-traffic sources such as waste containers, sewage systems, humans and open markets more dense in the densely populated historical city centre. Under high temperatures in summer these sources had the potential to increase the ambient levels of NH3 well above the urban-background-traffic-influenced UB measurement station. Measurements were used to assess major local emissions, sinks and diurnal evolution of NH3. The measured levels of NH3, especially high in the old city, may contribute to the high mean annual concentrations of secondary sulfate and nitrate measured in Barcelona compared with other cities in Spain affected by high traffic intensity. Ancillary measurements, including PM10, PM2.5, PM1 levels (Particulate Matter with aerodynamic diameter smaller than 10 μm, 2.5 μm, and 1 μm), gases and black carbon concentrations and meteorological data, were performed during the measurement campaign. The analysis of specific periods (3 special cases) during the campaign revealed that road traffic was a significant source of NH3. However, its effect was more evident at UB compared with CC where it was masked given the high levels of NH3 from non-traffic sources measured in the old city. The relationship between SO42- daily concentrations and gas-fraction ammonia (NH3/(NH3 + NH4+)) revealed that the gas-to-particle phase partitioning (volatilization or ammonium salts formation) also played an important role in the evolution of NH3 concentration in summer in Barcelona.

Summer ammonia measurements in a densely populated Mediterranean city

NASA Astrophysics Data System (ADS)

Pandolfi, M.; Amato, F.; Reche, C.; Alastuey, A.; Otjes, R. P.; Blom, M. J.; Querol, X.

2012-04-01

Real-time measurements of ambient concentrations of gas-phase ammonia were performed in Barcelona (NE Spain) in summer between May and September 2011. Two measurement sites were selected: one in an urban background traffic-influenced area (UB) and the other in the historical city centre (CC). Levels of ammonia were higher at CC (5.6 ± 2.1 μg m-3 or 7.5 ± 2.8 ppbv) compared with UB (2.2 ± 1.0 μg m-3 or 2.9 ± 1.3 ppbv). This difference is attributed to the contribution from non-traffic sources such as waste containers, sewage systems, humans and open markets more dense in the densely populated historical city centre. Under high temperatures in summer these sources had the potential to increase the ambient levels of ammonia well above the urban-background-traffic-influenced UB measurement station. Measurements were used to assess major local emissions, sinks and diurnal evolution of NH3. The measured levels of NH3, especially high in the old city, may contribute to the high mean annual concentrations of secondary sulfate and nitrate measured in Barcelona compared with other cities in Spain affected by high traffic intensity. Ancillary measurements, including PM10, PM2.5, PM1 levels (Particulate Matter with aerodynamic diameter smaller than 10 μm, 2.5 μm, and 1 μm), gases and black carbon concentrations and meteorological data, were performed during the measurement campaign. The analysis of specific periods (3 special cases) during the campaign revealed that road traffic was a significant source of NH3. However, its effect was more evident at UB compared with CC where it was masked given the high levels of NH3 from non-traffic sources measured in the old city. The relationship between SO42- daily concentrations and gas-fraction ammonia (NH3/(NH3+NH4+)) revealed that the gas-to-phase partitioning (volatilization or ammonium salts formation) also played an important role in the evolution of NH3 concentration in summer in Barcelona.

The 2007–2010 Q fever epidemic in The Netherlands: characteristics of notified acute Q fever patients and the association with dairy goat farming.

PubMed

Dijkstra, Frederika; van der Hoek, Wim; Wijers, Nancy; Schimmer, Barbara; Rietveld, Ariene; Wijkmans, Clementine J; Vellema, Piet; Schneeberger, Peter M

2012-02-01

We describe the Q fever epidemic in the Netherlands with emphasis on the epidemiological characteristics of acute Q fever patients and the association with veterinary factors. Data from 3264 notifications for acute Q fever in the period from 2007 through 2009 were analysed. The patients most affected were men, smokers and persons aged 40–60 years. Pneumonia was the most common clinical presentation (62% in 2007 and 2008). Only 3.2% of the patients were working in the agriculture sector and 0.5% in the meat-processing industry including abattoirs. Dairy goat farms with Coxiella burnetii-induced abortion waves were mainly located in the same area where human cases occurred. Airborne transmission of contaminated dust particles from commercial dairy goat farms in densely populated areas has probably caused this epidemic. In 2010, there was a sharp decline in the number of notified cases following the implementation of control measures on dairy goat and sheep farms such as vaccination, hygiene measures and culling of pregnant animals on infected farms. In combination with a rise in the human population with antibodies against C. burnetii, these have most likely ended the outbreak. Development of chronic Q fever in infected patients remains an important problem for years to come.

Polyploidization on SK-N-MC human neuroblastoma cells infected with herpes simplex virus 1.

PubMed

Karalyan, Zaven; Izmailyan, Roza; Karalova, Elena; Abroyan, Liana; Hakobyan, Lina; Avetisyan, Aida; Semerjyan, Zara

2016-01-01

Polyploidization is one of the most dramatic changes occurring within cell genome owing to various reasons including under many viral infections. We examined the impact of herpes simplex virus-1 (HSV-1) on SK-N-MC human neuroblastoma cell line. The infected cells were followed from 6 hours up to 96 hours post infection (hpi). A large number of polyploid cells with giant nuclei was observed under the influence of HSV-1 at 24 hpi with the DNA content of 32c to 64c or more, in comparison with control SK-N-MC cells that were characterized by relatively moderate values of ploidy, i.e. 8с to 16с (where 1c is the haploid amount of nuclear DNA found in normal diploid populations in G0/G1). After 48-96 hpi, the population of polyploid cells with giant nuclei decreased to the benchmark level. The SK-NMC cells infected with HSV-1 for 24 hours were stained with gallocyanine and monitored for cytological features. The infected cells underwent virus induced cellcell and nuclei fusion with the formation of dense nuclei syncytium. The metabolic activity of HSV-1 infected cells was higher in both nuclei and nucleoli when compared to control cells.

Linking rapid erosion of the Mekong River delta to human activities.

PubMed

Anthony, Edward J; Brunier, Guillaume; Besset, Manon; Goichot, Marc; Dussouillez, Philippe; Nguyen, Van Lap

2015-10-08

As international concern for the survival of deltas grows, the Mekong River delta, the world's third largest delta, densely populated, considered as Southeast Asia's most important food basket, and rich in biodiversity at the world scale, is also increasingly affected by human activities and exposed to subsidence and coastal erosion. Several dams have been constructed upstream of the delta and many more are now planned. We quantify from high-resolution SPOT 5 satellite images large-scale shoreline erosion and land loss between 2003 and 2012 that now affect over 50% of the once strongly advancing >600 km-long delta shoreline. Erosion, with no identified change in the river's discharge and in wave and wind conditions over this recent period, is consistent with: (1) a reported significant decrease in coastal surface suspended sediment from the Mekong that may be linked to dam retention of its sediment, (2) large-scale commercial sand mining in the river and delta channels, and (3) subsidence due to groundwater extraction. Shoreline erosion is already responsible for displacement of coastal populations. It is an additional hazard to the integrity of this Asian mega delta now considered particularly vulnerable to accelerated subsidence and sea-level rise, and will be exacerbated by future hydropower dams.

Use of a storm water retention system for conservation of regionally endangered fishes

USGS Publications Warehouse

Schaeffer, Jeffrey S.; Bland, James K.; Janssen, John

2012-01-01

Maintaining aquatic biodiversity in urban or suburban areas can be problematic because urban landscapes can be nearly devoid of aquatic habitats other than engineered basins for storm water management. These areas are usually of questionable value for fish, but we examined a case study in which five regionally imperiled fish species were reintroduced into an artificial storm water detention pond and subsequently thrived. Although not a formal experiment, postintroduction survey data suggested that three of the five species maintained high population densities for 10 years after initial stocking, and two persisted in lower numbers. Success was likely due to a combination of unique design features and prior habitat preparation that resulted in clear water conditions that supported dense vegetation. Stocked fish persisted despite occasional bouts of low dissolved oxygen and increased chloride levels resulting from road salt application within the watershed. Transplanted fish served as a source population for both research and further reintroduction experiments. We suggest that, for some fish species, habitat preservation has a middle ground between natural habitats and completely artificial environments that require constant husbandry and that storm water systems could be used to create engineered sanctuaries within the human landscape that have many potential benefits for both humans and fish.

Linking rapid erosion of the Mekong River delta to human activities

PubMed Central

Anthony, Edward J.; Brunier, Guillaume; Besset, Manon; Goichot, Marc; Dussouillez, Philippe; Nguyen, Van Lap

2015-01-01

As international concern for the survival of deltas grows, the Mekong River delta, the world’s third largest delta, densely populated, considered as Southeast Asia’s most important food basket, and rich in biodiversity at the world scale, is also increasingly affected by human activities and exposed to subsidence and coastal erosion. Several dams have been constructed upstream of the delta and many more are now planned. We quantify from high-resolution SPOT 5 satellite images large-scale shoreline erosion and land loss between 2003 and 2012 that now affect over 50% of the once strongly advancing >600 km-long delta shoreline. Erosion, with no identified change in the river’s discharge and in wave and wind conditions over this recent period, is consistent with: (1) a reported significant decrease in coastal surface suspended sediment from the Mekong that may be linked to dam retention of its sediment, (2) large-scale commercial sand mining in the river and delta channels, and (3) subsidence due to groundwater extraction. Shoreline erosion is already responsible for displacement of coastal populations. It is an additional hazard to the integrity of this Asian mega delta now considered particularly vulnerable to accelerated subsidence and sea-level rise, and will be exacerbated by future hydropower dams. PMID:26446752

A High-Resolution Chronology of Rapid Forest Transitions following Polynesian Arrival in New Zealand

PubMed Central

McWethy, David B.; Wilmshurst, Janet M.; Whitlock, Cathy; Wood, Jamie R.; McGlone, Matt S.

2014-01-01

Human-caused forest transitions are documented worldwide, especially during periods when land use by dense agriculturally-based populations intensified. However, the rate at which prehistoric human activities led to permanent deforestation is poorly resolved. In the South Island, New Zealand, the arrival of Polynesians c. 750 years ago resulted in dramatic forest loss and conversion of nearly half of native forests to open vegetation. This transformation, termed the Initial Burning Period, is documented in pollen and charcoal records, but its speed has been poorly constrained. High-resolution chronologies developed with a series of AMS radiocarbon dates from two lake sediment cores suggest the shift from forest to shrubland occurred within decades rather than centuries at drier sites. We examine two sites representing extreme examples of the magnitude of human impacts: a drier site that was inherently more vulnerable to human-set fires and a wetter, less burnable site. The astonishing rate of deforestation at the hands of small transient populations resulted from the intrinsic vulnerability of the native flora to fire and from positive feedbacks in post-fire vegetation recovery that increased landscape flammability. Spatially targeting burning in highly-flammable seral vegetation in forests rarely experiencing fire was sufficient to create an alternate fire-prone stable state. The New Zealand example illustrates how seemingly stable forest ecosystems can experience rapid and permanent conversions. Forest loss in New Zealand is among the fastest ecological transitions documented in the Holocene; yet equally rapid transitions can be expected in present-day regions wherever positive feedbacks support alternate fire-inhibiting, fire-prone stable states. PMID:25372150

Semantic Likelihood Models for Bayesian Inference in Human-Robot Interaction

NASA Astrophysics Data System (ADS)

Sweet, Nicholas

Autonomous systems, particularly unmanned aerial systems (UAS), remain limited in au- tonomous capabilities largely due to a poor understanding of their environment. Current sensors simply do not match human perceptive capabilities, impeding progress towards full autonomy. Recent work has shown the value of humans as sources of information within a human-robot team; in target applications, communicating human-generated 'soft data' to autonomous systems enables higher levels of autonomy through large, efficient information gains. This requires development of a 'human sensor model' that allows soft data fusion through Bayesian inference to update the probabilistic belief representations maintained by autonomous systems. Current human sensor models that capture linguistic inputs as semantic information are limited in their ability to generalize likelihood functions for semantic statements: they may be learned from dense data; they do not exploit the contextual information embedded within groundings; and they often limit human input to restrictive and simplistic interfaces. This work provides mechanisms to synthesize human sensor models from constraints based on easily attainable a priori knowledge, develops compression techniques to capture information-dense semantics, and investigates the problem of capturing and fusing semantic information contained within unstructured natural language. A robotic experimental testbed is also developed to validate the above contributions.

Maternal dietary counseling reduces consumption of energy-dense foods among infants: a randomized controlled trial.

PubMed

Vitolo, Marcia Regina; Bortolini, Gisele Ane; Campagnolo, Paula Dal Bo; Hoffman, Daniel J

2012-01-01

To evaluate the impact of a dietary counseling in reducing the intake of energy-dense foods by infants. A randomized controlled trial. São Leopoldo, Brazil. Mothers and infants of a low-income-group population were randomized into intervention (n = 163) and received dietary counseling during 10 home visits, or control (n = 234) groups. Child consumption of sugar-dense (SD) and lipid-dense (LD) foods at 12 to 16 months. The effect of the intervention was expressed by relative risks and 95% confidence intervals. Poisson regression analysis was used to determine the association between exclusive breastfeeding and the energy-dense foods intake. A smaller proportion of infants from the intervention group consumed candy, soft drinks, honey, cookies, chocolate, and salty snacks. In the intervention group, there was a reduction of 40% and 50% in the proportion of infants who consumed LD and SD foods, respectively. Being breastfed up to 6 months reduced the risk for consumption of LD and SD foods by 58% and 67%, respectively. Dietary counseling to mothers may be effective in reducing the consumption of energy-dense foods among infants, and it is helpful in improving early dietary habits. Copyright © 2012 Society for Nutrition Education and Behavior. Published by Elsevier Inc. All rights reserved.

Human alveolar bone cell proliferation, expression of osteoblastic phenotype, and matrix mineralization on porous titanium produced by powder metallurgy.

PubMed

Rosa, Adalberto Luiz; Crippa, Grasiele Edilaine; de Oliveira, Paulo Tambasco; Taba, Mario; Lefebvre, Louis-Philippe; Beloti, Marcio Mateus

2009-05-01

This study aimed at investigating the influence of the porous titanium (Ti) structure on the osteogenic cell behaviour. Porous Ti discs were fabricated by the powder metallurgy process with the pore size typically between 50 and 400 microm and a porosity of 60%. Osteogenic cells obtained from human alveolar bone were cultured until subconfluence and subcultured on dense Ti (control) and porous Ti for periods of up to 17 days. Cultures grown on porous Ti exhibited increased cell proliferation and total protein content, and lower levels of alkaline phosphatase (ALP) activity than on dense Ti. In general, gene expression of osteoblastic markers-runt-related transcription factor 2, collagen type I, alkaline phosphatase, bone morphogenetic protein-7, and osteocalcin was lower at day 7 and higher at day 17 in cultures grown on porous Ti compared with dense Ti, a finding consistent with the enhanced growth rate for such cultures. The amount of mineralized matrix was greater on porous Ti compared with the dense one. These results indicate that the porous Ti is an appropriate substrate for osteogenic cell adhesion, proliferation, and production of a mineralized matrix. Because of the three-dimensional environment it provides, porous Ti should be considered an advantageous substrate for promoting desirable implant surface-bone interactions.

Response of small mammal populations to fuel treatment and precipitation in a ponderosa pine forest, New Mexico

Treesearch

Karen E. Bagne; Deborah M. Finch

2009-01-01

Mechanical and fire treatments are commonly used to reduce fuels where land use practices have encouraged accumulation of woody debris and high densities of trees. Treatments focus on restoration of vegetation structure, but will also affect wildlife populations. Small mammal populations were monitored before and after dense tree stands were thinned on 2,800 ha in NM,...

Conservation hotspots for marine turtle nesting in the United States based on coastal development.

PubMed

Fuentes, Mariana M P B; Gredzens, Christian; Bateman, Brooke L; Boettcher, Ruth; Ceriani, Simona A; Godfrey, Matthew H; Helmers, David; Ingram, Dianne K; Kamrowski, Ruth L; Pate, Michelle; Pressey, Robert L; Radeloff, Volker C

2016-12-01

Coastal areas provide nesting habitat for marine turtles that is critical for the persistence of their populations. However, many coastal areas are highly affected by coastal development, which affects the reproductive success of marine turtles. Knowing the extent to which nesting areas are exposed to these threats is essential to guide management initiatives. This information is particularly important for coastal areas with both high nesting density and dense human development, a combination that is common in the United States. We assessed the extent to which nesting areas of the loggerhead (Caretta caretta), the green (Chelonia mydas), the Kemp's ridley (Lepidochelys kempii), and leatherback turtles (Dermochelys coriacea) in the continental United States are exposed to coastal development and identified conservation hotspots that currently have high reproductive importance and either face high exposure to coastal development (needing intervention), or have low exposure to coastal development, and are good candidates for continued and future protection. Night-time light, housing, and population density were used as proxies for coastal development and human disturbance. About 81.6% of nesting areas were exposed to housing and human population, and 97.8% were exposed to light pollution. Further, most (>65%) of the very high- and high-density nesting areas for each species/subpopulation, except for the Kemp's ridley, were exposed to coastal development. Forty-nine nesting sites were selected as conservation hotspots; of those high-density nesting sites, 49% were sites with no/low exposure to coastal development and the other 51% were exposed to high-density coastal development. Conservation strategies need to account for ~66.8% of all marine turtle nesting areas being on private land and for nesting sites being exposed to large numbers of seasonal residents. © 2016 by the Ecological Society of America.

Research on vulnerability assessments of the Huanghe (Yellow River) delta

NASA Astrophysics Data System (ADS)

qiao, shuqing; shi, xuefa

2014-05-01

Coastal zone located at the juncture of the sea, river and land, and under the influence of both land and ocean (including atmosphere), especially the sea-level rise and human activities, are vulnerable to environment and ecology. At highest risk are coastal zone of South, Southeast and East Asia with dense populations, low elevations and inadequate adaptive capacity. In China, more than 40% of the population live on the 15% of the land in coastal area and more than 70% cities located around the coastal area. The Chinese coastal region, especially river delta area has been experienced erosion, seawater intrusion and decrease in biodiversity under the combined influence of sea-level rise, tectonic subsidence and flooding. Furthermore, some kinds of human activity, such as land use, building, dam construction, reclamation from the sea and waste dumping strengthen the vulnerability of environment and ecosystem in coastal region. The coastal hazards (e.g. coastal erosion, seawater intrusion, land subsidence) and vulnerability of the Huanghe (Yelllow River) delta area are studied during the past several years. A systematic coastal assessment index is built and an evaluation model is developed using the development platform of Visual studio.Net 2005. The assessment index system includes two parts, inherent (sea level rise rate, elevation, morphology, water and sediment discharge, mean tidal range, mean wave height etc) and specific vulnerability index (population density, GDP, land utilization, protection structures etc). The assessment index are determined the weight using Analytic hierarchy process (AHP) method. Based on the research results, we better understand the current status and future change of coastal vulnerability and hazards, discuss the impact of the natural possess and human activities. Furthermore, we provide defending strategies for coastal zone vulnerability and typical coastal hazards.

Physiological correlates of ecological divergence along an urbanization gradient: differential tolerance to ammonia among molecular forms of the malaria mosquito Anopheles gambiae

PubMed Central

2013-01-01

Background Limitations in the ability of organisms to tolerate environmental stressors affect their fundamental ecological niche and constrain their distribution to specific habitats. Evolution of tolerance, therefore, can engender ecological niche dynamics. Forest populations of the afro-tropical malaria mosquito Anopheles gambiae have been shown to adapt to historically unsuitable larval habitats polluted with decaying organic matter that are found in densely populated urban agglomerates of Cameroon. This process has resulted in niche expansion from rural to urban environments that is associated with cryptic speciation and ecological divergence of two evolutionarily significant units within this taxon, the molecular forms M and S, among which reproductive isolation is significant but still incomplete. Habitat segregation between the two forms results in a mosaic distribution of clinally parapatric patches, with the M form predominating in the centre of urban agglomerates and the S form in the surrounding rural localities. We hypothesized that development of tolerance to nitrogenous pollutants derived from the decomposition of organic matter, among which ammonia is the most toxic to aquatic organisms, may affect this pattern of distribution and process of niche expansion by the M form. Results Acute toxicity bioassays indicated that populations of the two molecular forms occurring at the extremes of an urbanization gradient in Yaounde, the capital of Cameroon, differed in their response to ammonia. The regression lines best describing the dose-mortality profile differed in the scale of the explanatory variable (ammonia concentration log-transformed for the S form and linear for the M form), and in slope (steeper for the S form and shallower for the M form). These features reflected differences in the frequency distribution of individual tolerance thresholds in the two populations as assessed by probit analysis, with the M form exhibiting a greater mean and variance compared to the S form. Conclusions In agreement with expectations based on the pattern of habitat partitioning and exposure to ammonia in larval habitats in Yaounde, the M form showed greater tolerance to ammonia compared to the S form. This trait may be part of the physiological machinery allowing forest populations of the M form to colonize polluted larval habitats, which is at the heart of its niche expansion in densely populated human settlements in Cameroon. PMID:23294940

Prehistoric mitochondrial DNA of domesticate animals supports a 13th century exodus from the northern US southwest

PubMed Central

Judd, Kathleen; Monroe, Cara; Hilldorfer, Lindsay; Cordray, Connor; Schad, Rebecca; Reams, Erin

2017-01-01

The 13th century Puebloan depopulation of the Four Corners region of the US Southwest is an iconic episode in world prehistory. Studies of its causes, as well as its consequences, have a bearing not only on archaeological method and theory, but also social responses to climate change, the sociology of social movements, and contemporary patterns of cultural diversity. Previous research has debated the demographic scale, destinations, and impacts of Four Corners migrants. Much of this uncertainty stems from the substantial differences in material culture between the Four Corners vs. hypothesized destination areas. Comparable biological evidence has been difficult to obtain due to the complete departure of farmers from the Four Corners in the 13th century CE and restrictions on sampling human remains. As an alternative, patterns of genetic variation among domesticated species were used to address the role of migration in this collapse. We collected mitochondrial haplotypic data from dog (Canis lupus familiaris) and turkey (Meleagris gallopavo) remains from archaeological sites in the most densely-populated portion of the Four Corners region, and the most commonly proposed destination area for that population under migration scenarios. Results are consistent with a large-scale migration of humans, accompanied by their domestic turkeys, during the 13th century CE. These results support scenarios that suggest contemporary Pueblo peoples of the Northern Rio Grande are biological and cultural descendants of Four Corners populations. PMID:28746407

Laser Heating in a Dense Plasma Focus.

DTIC Science & Technology

The report is divided in two parts. In the first part an account is given of the measurement of the momentum distribution of the deuterons ejected from a dense plasma focus . The results show the existence of a pronounced non-Maxwellian distribution and a small population of deuterons accelerated to the voltage of the condenser bank. In the second part theoretical calculation of laser heating establish the presence of large density gradient which probably accounts for the large currents detected in such plasmas. (Author)

The disease complex of the gypsy moth. 1. Major components

Treesearch

R.W. Campbell; J.D. Podgwaite

1971-01-01

A study was undertaken to elucidate the impact of the various components of disease on natural populations of the gypsy moth, Porthetria dispar. Diseased larvae from both sparse and dense populations were examined and categorized on the basis of etiologic and nonetiologic mortality factors. Results indicated a significantly higher incidence of...

Gene-centric meta-analysis of lipid traits in African, East Asian and Hispanic populations

USDA-ARS?s Scientific Manuscript database

Meta-analyses of European populations has successfully identified genetic variants in over 100 loci associated with lipid levels, but our knowledge in other ethnicities remains limited. To address this, we performed dense genotyping of circa 2,000 candidate genes in 7,657 African Americans, 1,315 Hi...

Entomological aspects of filariasis control in Sri Lanka

PubMed Central

Lambrecht, F. L.

1974-01-01

Historical events and suitable environmental conditions in the southwestern coastal areas of Sri Lanka have led to the establishment of a zone of endemic filariasis caused by Wuchereria bancrofti and transmitted by Culex pipiens fatigans. The previous Brugia malayi foci, scattered over widely dispersed areas of the island, were apparently completely eliminated as a result of control of the Mansonia vectors by the destruction of the larval host plants in their swamp habitats. Control measures by the Anti-Filariasis Campaign against W. bancrofti and C. p. fatigans have greatly reduced the human infection rates in the endemic coastal belt and have kept the rate in the dense population to less than 1% over the last several years. This paper assesses the entomological aspects of the control programme during the years 1970-72. PMID:4619057

Thick-Market Effects and Churning in the Labor Market: Evidence from U.S. Cities*

PubMed Central

Bleakley, Hoyt; Lin, Jeffrey

2012-01-01

Using U.S. Census microdata, we show that, on average, workers change occupation and industry less in more densely populated areas. The result is robust to standard demographic controls, as well as to including aggregate measures of human capital and sectoral mix. Analysis of the displaced worker surveys shows that this effect is present in cases of involuntary separation as well. On the other hand, we actually find the opposite result (higher rates of occupational and industrial switching) for the subsample of younger workers. These results provide evidence in favor of increasing-returns-to-scale matching in labor markets. Results from a back-of-the-envelope calibration suggest that this mechanism has an important role in raising both wages and returns to experience in denser areas. PMID:24039316

Movers and shakers

PubMed Central

Mills, Susan; Shanahan, Fergus; Stanton, Catherine; Hill, Colin; Coffey, Aidan; Ross, R. Paul

2013-01-01

The human intestinal microbiota is one of the most densely populated ecosystems on Earth, containing up to 1013 bacteria/g and in some respects can be considered an organ itself given its role in human health. Bacteriophages (phages) are the most abundant replicating entities on the planet and thrive wherever their bacterial hosts exist. They undoubtedly influence the dominant microbial populations in many ecosystems including the human intestine. Within this setting, lysogeny appears to be the preferred life cycle, presumably due to nutrient limitations and lack of suitable hosts protected in biofilms, hence the predator/prey dynamic observed in many ecosystems is absent. On the other hand, free virulent phages in the gut are more common among sufferers of intestinal diseases and have been shown to increase with antibiotic usage. Many of these phages evolve from prophages of intestinal bacteria and emerge under conditions where their bacterial hosts encounter stress suggesting that prophages can significantly alter the microbial community composition. Based on these observations, we propose the “community shuffling” model which hypothesizes that prophage induction contributes to intestinal dysbiosis by altering the ratio of symbionts to pathobionts, enabling pathobiont niche reoccupation. The consequences of the increased phage load on the mammalian immune system are also addressed. While this is an area of intestinal biology which has received little attention, this review assembles evidence from the literature which supports the role of phages as one of the biological drivers behind the composition of the gut microbiota. PMID:23022738

Geographic variation in racial disparities in child maltreatment: The influence of county poverty and population density.

PubMed

Maguire-Jack, Kathryn; Lanier, Paul; Johnson-Motoyama, Michelle; Welch, Hannah; Dineen, Michael

2015-09-01

There are documented disparities in the rates at which black children come into contact with the child welfare system in the United States compared to white children. A great deal of research has proliferated aimed at understanding whether systematic biases or differential rates of risk among different groups drive these disparities (Drake et al., 2011). In the current study, county rates of maltreatment disparity are compared across the United States and examined in relation to rates of poverty disparity as well as population density. Specifically, using hierarchical linear modeling with a spatially lagged dependent variable, the current study examined data from the National Child Abuse and Neglect Data System (NCANDS) and found that poverty disparities were associated with rates of maltreatment disparities, and densely populated metropolitan counties tended to have the greatest levels of maltreatment disparity for both black and Hispanic children. A significant curvilinear relationship was also observed between these variables, such that in addition to the most densely populated counties, the most sparsely populated counties also tended to have higher rates of maltreatment disparity for black and Hispanic children. Copyright © 2015 Elsevier Ltd. All rights reserved.

Extinction rate, historical population structure and ecological role of the Caribbean monk seal.

PubMed

McClenachan, Loren; Cooper, Andrew B

2008-06-22

The productivity and biomass of pristine coral reef ecosystems is poorly understood, particularly in the Caribbean where communities have been impacted by overfishing and multiple other stressors over centuries. Using historical data on the spatial distribution and abundance of the extinct Caribbean monk seal (Monachus tropicalis), this study reconstructs the population size, structure and ecological role of this once common predator within coral reef communities, and provides evidence that historical reefs supported biomasses of fishes and invertebrates up to six times greater than those found on typical modern Caribbean reefs. An estimated 233,000-338,000 monk seals were distributed among 13 colonies across the Caribbean. The biomass of reef fishes and invertebrates required to support historical seal populations was 732-1018 gm(-2) of reefs, which exceeds that found on any Caribbean reef today and is comparable with those measured in remote Pacific reefs. Quantitative estimates of historically dense monk seal colonies and their consumption rates on pristine reefs provide concrete data on the magnitude of decline in animal biomass on Caribbean coral reefs. Realistic reconstruction of these past ecosystems is critical to understanding the profound and long-lasting effect of human hunting on the functioning of coral reef ecosystems.

Key Techniques and Risk Management for the Application of the Pile-Beam-Arch (PBA) Excavation Method: A Case Study of the Zhongjie Subway Station

PubMed Central

Guan, Yong-ping; Zhao, Wen; Li, Shen-gang; Zhang, Guo-bin

2014-01-01

The design and construction of shallow-buried tunnels in densely populated urban areas involve many challenges. The ground movements induced by tunneling effects pose potential risks to infrastructure such as surface buildings, pipelines, and roads. In this paper, a case study of the Zhongjie subway station located in Shenyang, China, is examined to investigate the key construction techniques and the influence of the Pile-Beam-Arch (PBA) excavation method on the surrounding environment. This case study discusses the primary risk factors affecting the environmental safety and summarizes the corresponding risk mitigation measures and key techniques for subway station construction using the PBA excavation method in a densely populated urban area. PMID:25221783

Modeling reduction of the Urban Heat Island effect to counter-act the effects of climate change in densely built-up areas

NASA Astrophysics Data System (ADS)

Andre, Konrad; Zuvela-Aloise, Maja; Lettmayer, Gudrun; Schwaiger, Hannes Peter; Kaltenegger, Ingrid; Bird, David Neil; Woess-Gallasch, Susanne

2017-04-01

The phenomenon of Urban Heat Islands (UHIs) observed in cities, caused by changes in energy balance due to the structural development of the city as well as by sealed surfaces and a lack of vegetation, is expected to strengthen in the future and will further contribute to heat stress, creating an increased need for energy for cooling and ventilation as well as lowering human comfort. Due to a changing climate, rising heat stress, pronounced by an increased intensity or frequency of heat waves, could have far reaching implications for major Austrian cities in the near future. Simultaneous to this expected increasing of the already existing UHI-effect, it is observable, that continuous densification of the core parts of cities is being intensified through implemented traditional urban planning measures. This is particular relevant for high densely populated districts of the city. Several possible counteractions how to address this challenge are already known, partly investigated in urban modeling studies on the effects of modifying the reflective properties of buildings and urban areas for the city of Vienna. On this experience, within the Austrian FFG and KLIEN Smart Cities project JACKY COOL CHECK (Project Nr. 855554), a wide set of measures to reduce heat stress, consisting of e.g. unsealed surfaces, green areas, green roofs, improve reflective properties of different surfaces etc., for the densely built-up residential and business district of Jakomini in the city of Graz/Styria is investigated, to gain decisive data pointing out the peculiarities of UHIs and the potential cooling effects of these target measures for this local specific area. These results serving as a basis for the selection of sustainable measures that will be implemented, in coordination with local stakeholders and considering their interests.

Impacts of land use on Indian mangrove forest carbon stocks: Implications for conservation and management.

PubMed

Bhomia, R K; MacKenzie, R A; Murdiyarso, D; Sasmito, S D; Purbopuspito, J

2016-07-01

Globally, mangrove forests represents only 0.7% of world's tropical forested area but are highly threatened due to susceptibility to climate change, sea level rise, and increasing pressures from human population growth in coastal regions. Our study was carried out in the Bhitarkanika Conservation Area (BCA), the second-largest mangrove area in eastern India. We assessed total ecosystem carbon (C) stocks at four land use types representing varying degree of disturbances. Ranked in order of increasing impacts, these sites included dense mangrove forests, scrub mangroves, restored/planted mangroves, and abandoned aquaculture ponds. These impacts include both natural and/or anthropogenic disturbances causing stress, degradation, and destruction of mangroves. Mean vegetation C stocks (including both above- and belowground pools; mean ± standard error) in aquaculture, planted, scrub, and dense mangroves were 0, 7 ± 4, 65 ± 11 and 100 ± 11 Mg C/ha, respectively. Average soil C pools for aquaculture, planted, scrub, and dense mangroves were 61 ± 8, 92 ± 20, 177 ± 14, and 134 ± 17 Mg C/ha, respectively. Mangrove soils constituted largest fraction of total ecosystem C stocks at all sampled sites (aquaculture [100%], planted [90%], scrub [72%], and dense mangrove [57%]). Within BCA, the four studied land use types covered an area of ~167 km 2 and the total ecosystem C stocks were 0.07 Tg C for aquaculture (~12 km 2 ), 0.25 Tg C for planted/ restored mangrove (~24 km 2 ), 2.29 teragrams (Tg) Tg C for scrub (~93 km 2 ), and 0.89 Tg C for dense mangroves (~38 km 2 ). Although BCA is protected under Indian wildlife protection and conservation laws, ~150 000 people inhabit this area and are directly or indirectly dependent on mangrove resources for sustenance. Estimates of C stocks of Bhitarkanika mangroves and recognition of their role as a C repository could provide an additional reason to support conservation and restoration of Bhitarkanika mangroves. Harvesting or destructive exploitation of mangroves by local communities for economic gains can potentially be minimized by enabling these communities to avail themselves of carbon offset/conservation payments under approved climate change mitigation strategies and actions. © 2016 by the Ecological Society of America.

Human symbionts inject and neutralize antibacterial toxins to persist in the gut.

PubMed

Wexler, Aaron G; Bao, Yiqiao; Whitney, John C; Bobay, Louis-Marie; Xavier, Joao B; Schofield, Whitman B; Barry, Natasha A; Russell, Alistair B; Tran, Bao Q; Goo, Young Ah; Goodlett, David R; Ochman, Howard; Mougous, Joseph D; Goodman, Andrew L

2016-03-29

The human gut microbiome is a dynamic and densely populated microbial community that can provide important benefits to its host. Cooperation and competition for nutrients among its constituents only partially explain community composition and interpersonal variation. Notably, certain human-associated Bacteroidetes--one of two major phyla in the gut--also encode machinery for contact-dependent interbacterial antagonism, but its impact within gut microbial communities remains unknown. Here we report that prominent human gut symbionts persist in the gut through continuous attack on their immediate neighbors. Our analysis of just one of the hundreds of species in these communities reveals 12 candidate antibacterial effector loci that can exist in 32 combinations. Through the use of secretome studies, in vitro bacterial interaction assays and multiple mouse models, we uncover strain-specific effector/immunity repertoires that can predict interbacterial interactions in vitro and in vivo, and find that some of these strains avoid contact-dependent killing by accumulating immunity genes to effectors that they do not encode. Effector transmission rates in live animals can exceed 1 billion events per minute per gram of colonic contents, and multiphylum communities of human gut commensals can partially protect sensitive strains from these attacks. Together, these results suggest that gut microbes can determine their interactions through direct contact. An understanding of the strategies human gut symbionts have evolved to target other members of this community may provide new approaches for microbiome manipulation.

Global Impacts of Long-Term Land Cover Changes Within China's Densely Populated Rural Regions

NASA Astrophysics Data System (ADS)

Ellis, E. C.

2006-12-01

Long-term changes in land cover are usually investigated in terms of large-scale change processes such as urban expansion, deforestation and land conversion to agriculture. Yet China's densely populated agricultural regions, which cover more than 2 million square kilometers of Monsoon Asia, have been transformed profoundly over the past fifty years by fine-scale changes in land cover caused by unprecedented changes in population, technology and social conditions. Using a regional sampling and upscaling design coupled with high-resolution landscape change measurements at five field sites, we investigated long-term changes in land cover and ecological processes, circa 1945 to 2002, within and across China's densely populated agricultural regions. As expected, the construction of buildings and roads increased impervious surface area over time, but the total net increase was surprising, being similar in magnitude to the total current extent of China's cities. Agricultural land area declined over the same period, while tree cover increased, by about 10%, driven by tree planting and regrowth around new buildings, the introduction of perennial agriculture, improved forestry, and declines in annual crop cultivation. Though changes in impervious surface areas were closely related to changes in population density, long-term changes in agricultural land and tree cover were unrelated to populated density and required explanation by more complex models with strong regional and biophysical components. Moreover, most of these changes occurred primarily at fine spatial scales (< 30 m), under the threshold for conventional global and regional land cover change measurements. Given that these changes in built structures and vegetation cover have the potential to contribute substantially to regional and global changes in biogeochemistry, hydrology, and land-atmosphere interactions, future investigations of these changes and their impacts across Monsoon Asia would benefit from models that incorporate fine-scale landscape structure and its changes over time.

Discovering functional DNA elements using population genomic information: a proof of concept using human mtDNA.

PubMed

Schrider, Daniel R; Kern, Andrew D

2014-06-09

Identifying the complete set of functional elements within the human genome would be a windfall for multiple areas of biological research including medicine, molecular biology, and evolution. Complete knowledge of function would aid in the prioritization of loci when searching for the genetic bases of disease or adaptive phenotypes. Because mutations that disrupt function are disfavored by natural selection, purifying selection leaves a detectable signature within functional elements; accordingly, this signal has been exploited for over a decade through the use of genomic comparisons of distantly related species. While this is so, the functional complement of the genome changes extensively across time and between lineages; therefore, evidence of the current action of purifying selection in humans is essential. Because the removal of deleterious mutations by natural selection also reduces within-species genetic diversity within functional loci, dense population genetic data have the potential to reveal genomic elements that are currently functional. Here, we assess the potential of this approach by examining an ultradeep sample of human mitochondrial genomes (n = 16,411). We show that the high density of polymorphism in this data set precisely delineates regions experiencing purifying selection. Furthermore, we show that the number of segregating alleles at a site is strongly correlated with its divergence across species after accounting for known mutational biases in human mitochondrial DNA (ρ = 0.51; P < 2.2 × 10(-16)). These two measures track one another at a remarkably fine scale across many loci-a correlation that is purely the result of natural selection. Our results demonstrate that genetic variation has the potential to reveal with surprising precision which regions in the genome are currently performing important functions and likely to have deleterious fitness effects when mutated. As more complete human genomes are sequenced, similar power to reveal purifying selection may be achievable in the human nuclear genome. © The Author(s) 2014. Published by Oxford University Press on behalf of the Society for Molecular Biology and Evolution.

Threats of Zika virus transmission for Asia and its Hindu-Kush Himalayan region.

PubMed

Dhimal, Meghnath; Dahal, Sushma; Dhimal, Mandira Lamichhane; Mishra, Shiva Raj; Karki, Khem B; Aryal, Krishna Kumar; Haque, Ubydul; Kabir, Md Iqbal; Guin, Pradeep; Butt, Azeem Mehmood; Harapan, Harapan; Liu, Qi-Yong; Chu, Cordia; Montag, Doreen; Groneberg, David Alexander; Pandey, Basu Dev; Kuch, Ulrich; Müller, Ruth

2018-05-15

Asia and its Hindu Kush Himalayan (HKH) region is particularly vulnerable to environmental change, especially climate and land use changes further influenced by rapid population growth, high level of poverty and unsustainable development. Asia has been a hotspot of dengue fever and chikungunya mainly due to its dense human population, unplanned urbanization and poverty. In an urban cycle, dengue virus (DENV) and chikungunya virus (CHIKV) are transmitted by Aedes aegypti and Ae. albopictus mosquitoes which are also competent vectors of Zika virus (ZIKV). Over the last decade, DENV and CHIKV transmissions by Ae. aegypti have extended to the Himalayan countries of Bhutan and Nepal and ZIKV could follow in the footsteps of these viruses in the HKH region. The already established distribution of human-biting Aedes mosquito vectors and a naïve population with lack of immunity against ZIKV places the HKH region at a higher risk of ZIKV. Some of the countries in the HKH region have already reported ZIKV cases. We have documented an increasing threat of ZIKV in Asia and its HKH region because of the high abundance and wide distribution of human-biting mosquito vectors, climate change, poverty, report of indigenous cases in the region, increasing numbers of imported cases and a naïve population with lack of immunity against ZIKV. An outbreak anywhere is potentially a threat everywhere. Therefore, in order to ensure international health security, all efforts to prevent, detect, and respond to ZIKV ought to be intensified now in Asia and its HKH region. To prepare for possible ZIKV outbreaks, Asia and the HKH region can also learn from the success stories and strategies adopted by other regions and countries in preventing ZIKV and associated complications. The future control strategies for DENV, CHIKV and ZIKV should be considered in tandem with the threat to human well-being that is posed by other emerging and re-emerging vector-borne and zoonotic diseases, and by the continuing urgent need to strengthen public primary healthcare systems in the region.

Occurrence of drugs of abuse and benzodiazepines in river waters from the Madrid Region (Central Spain).

PubMed

Mendoza, A; López de Alda, M; González-Alonso, S; Mastroianni, N; Barceló, D; Valcárcel, Y

2014-01-01

This work investigates, for the first time, the occurrence of 10 drugs of abuse, six metabolites, and three benzodiazepines in surface waters from the Jarama and Manzanares Rivers in the Madrid Region, the most densely populated area in Spain and one of the most densely populated in Europe. The results of this study have shown the presence of 14 out of the 19 compounds analyzed at concentrations ranging from 1.45 to 1020 ng L(-1). The most ubiquitous compounds, found in 100% of the samples, were the cocaine metabolite benzoylecgonine (BE), the amphetamine-like compound ephedrine (EPH), the opioids morphine (MOR), methadone (METH), and the METH metabolite 2-ethylene-1,5-dimethyl-3,3-diphenylpyrrolidine (EDDP), and the three investigated benzodiazepines alprazolam (ALP), diazepam (DIA) and lorazepam (LOR). Meanwhile, the largest concentrations observed corresponded to EPH (up to 1020 ng L(-1)), BE (823 ng L(-1)), EDDP (151 ng L(-1)), and LOR (167 ng L(-1)). The only not detected compounds were heroin (HER) and its metabolite 6-acetylmorphine (6ACM), lysergic acid diethylamide (LSD) and its metabolite 2-oxo-3-hydroxy-LSD (OH-LSD), and Δ(9)-tetrahydrocannabinol (THC). Overall, the levels measured are comparatively higher than those previously reported in Europe. Comparison of the results obtained for samples collected on different days (Thursday and Sunday) did not show meaningful differences between weekdays and weekends. The lack of (eco)toxicological data does not permit to predict or disregard potential adverse effects on wildlife. Risk assessment in humans would require further knowledge, not currently available, on exposure to these compounds through other routes like drinking water and/or food. Copyright © 2013 Elsevier Ltd. All rights reserved.

Temporal Trends of NO2, CO and their Relation to the Fire Occurrences over the Indo-Gangetic Plain

NASA Astrophysics Data System (ADS)

Pandey, A. K.; Kumar, K.

2016-12-01

Air pollution is an environmental issue that has a gigantic impact on human health, and it is a major problem in the densely populated regions throughout the world. Situated in the foothills of the great Himalayas Indo-Gangetic Plain (IGP) is among one of the most densely populated regions of the earth. NO2 and CO are among major air pollutants which affect the air quality of IGP predominantly. In the present study, we studied the temporal trends of NO2, CO and fire count over the IGP region. Further, we investigated the role of the fire occurrences in the ambient NO2 and CO levels. We used MODIS instrument (Aqua satellite), OMI sensor and AIRS instrument data for fire count, Nitrogen Dioxide (NO2) tropospheric column and Carbon monoxide (CO) column study respectively. The IGP is divided into three part geographically i.e. Eastern (E-IGP), Central (C-IGP) and Western (W-IGP). A higher columnar CO concentration is observed in the E-IGP whereas NO2 concentration is highest in the W-IGP. A higher NO2 concentration is obtained in winter followed by summer and a minimum in monsoon months throughout the IGP. Columnar CO concentration is higher in the E-IGP and its concentration is maximum in pre-monsoon months and minimum in the monsoon months. Fire pixel count is highest in the W-IGP with peak twice every year i.e. in the April - May and October - November corresponding to the harvest period in the Rabi-Kharif cropping system. We also obtained a significant positive correlation between fire occurrences and columnar NO2 & CO levels over the IGP which shows the biomass burning practices associated with the agriculture influences the NO2 and CO concentration in the atmosphere.

Potential and Actual Health Hazards in the Dense Urban Operational Environment: Critical Gaps and Solutions for Military Occupational Health.

PubMed

Patterson, Steven L; Dancy, Blair C R; Ippolito, Danielle L; Stallings, Jonathan D

2017-11-01

: This paper presents environmental health risks which are prevalent in dense urban environments.We review the current literature and recommendations proposed by environmental medicine experts in a 2-day symposium sponsored by the Department of Defense and supported by the Johns Hopkins University Applied Physics Laboratory.Key hazards in the dense urban operational environment include toxic industrial chemicals and materials, water pollution and sewage, and air pollution. Four critical gaps in environmental medicine were identified: prioritizing chemical and environmental concerns, developing mobile decision aids, personalized health assessments, and better real-time health biomonitoring.As populations continue to concentrate in cities, civilian and military leaders will need to meet emerging environmental health concerns by developing and delivering adequate technology and policy solutions.

A Bayesian Framework for Human Body Pose Tracking from Depth Image Sequences

PubMed Central

Zhu, Youding; Fujimura, Kikuo

2010-01-01

This paper addresses the problem of accurate and robust tracking of 3D human body pose from depth image sequences. Recovering the large number of degrees of freedom in human body movements from a depth image sequence is challenging due to the need to resolve the depth ambiguity caused by self-occlusions and the difficulty to recover from tracking failure. Human body poses could be estimated through model fitting using dense correspondences between depth data and an articulated human model (local optimization method). Although it usually achieves a high accuracy due to dense correspondences, it may fail to recover from tracking failure. Alternately, human pose may be reconstructed by detecting and tracking human body anatomical landmarks (key-points) based on low-level depth image analysis. While this method (key-point based method) is robust and recovers from tracking failure, its pose estimation accuracy depends solely on image-based localization accuracy of key-points. To address these limitations, we present a flexible Bayesian framework for integrating pose estimation results obtained by methods based on key-points and local optimization. Experimental results are shown and performance comparison is presented to demonstrate the effectiveness of the proposed approach. PMID:22399933

Identifying signatures of natural selection in Tibetan and Andean populations using dense genome scan data.

PubMed

Bigham, Abigail; Bauchet, Marc; Pinto, Dalila; Mao, Xianyun; Akey, Joshua M; Mei, Rui; Scherer, Stephen W; Julian, Colleen G; Wilson, Megan J; López Herráez, David; Brutsaert, Tom; Parra, Esteban J; Moore, Lorna G; Shriver, Mark D

2010-09-09

High-altitude hypoxia (reduced inspired oxygen tension due to decreased barometric pressure) exerts severe physiological stress on the human body. Two high-altitude regions where humans have lived for millennia are the Andean Altiplano and the Tibetan Plateau. Populations living in these regions exhibit unique circulatory, respiratory, and hematological adaptations to life at high altitude. Although these responses have been well characterized physiologically, their underlying genetic basis remains unknown. We performed a genome scan to identify genes showing evidence of adaptation to hypoxia. We looked across each chromosome to identify genomic regions with previously unknown function with respect to altitude phenotypes. In addition, groups of genes functioning in oxygen metabolism and sensing were examined to test the hypothesis that particular pathways have been involved in genetic adaptation to altitude. Applying four population genetic statistics commonly used for detecting signatures of natural selection, we identified selection-nominated candidate genes and gene regions in these two populations (Andeans and Tibetans) separately. The Tibetan and Andean patterns of genetic adaptation are largely distinct from one another, with both populations showing evidence of positive natural selection in different genes or gene regions. Interestingly, one gene previously known to be important in cellular oxygen sensing, EGLN1 (also known as PHD2), shows evidence of positive selection in both Tibetans and Andeans. However, the pattern of variation for this gene differs between the two populations. Our results indicate that several key HIF-regulatory and targeted genes are responsible for adaptation to high altitude in Andeans and Tibetans, and several different chromosomal regions are implicated in the putative response to selection. These data suggest a genetic role in high-altitude adaption and provide a basis for future genotype/phenotype association studies necessary to confirm the role of selection-nominated candidate genes and gene regions in adaptation to altitude.

Identifying Signatures of Natural Selection in Tibetan and Andean Populations Using Dense Genome Scan Data

PubMed Central

Bigham, Abigail; Bauchet, Marc; Pinto, Dalila; Mao, Xianyun; Akey, Joshua M.; Mei, Rui; Scherer, Stephen W.; Julian, Colleen G.; Wilson, Megan J.; López Herráez, David; Brutsaert, Tom; Parra, Esteban J.; Moore, Lorna G.; Shriver, Mark D.

2010-01-01

High-altitude hypoxia (reduced inspired oxygen tension due to decreased barometric pressure) exerts severe physiological stress on the human body. Two high-altitude regions where humans have lived for millennia are the Andean Altiplano and the Tibetan Plateau. Populations living in these regions exhibit unique circulatory, respiratory, and hematological adaptations to life at high altitude. Although these responses have been well characterized physiologically, their underlying genetic basis remains unknown. We performed a genome scan to identify genes showing evidence of adaptation to hypoxia. We looked across each chromosome to identify genomic regions with previously unknown function with respect to altitude phenotypes. In addition, groups of genes functioning in oxygen metabolism and sensing were examined to test the hypothesis that particular pathways have been involved in genetic adaptation to altitude. Applying four population genetic statistics commonly used for detecting signatures of natural selection, we identified selection-nominated candidate genes and gene regions in these two populations (Andeans and Tibetans) separately. The Tibetan and Andean patterns of genetic adaptation are largely distinct from one another, with both populations showing evidence of positive natural selection in different genes or gene regions. Interestingly, one gene previously known to be important in cellular oxygen sensing, EGLN1 (also known as PHD2), shows evidence of positive selection in both Tibetans and Andeans. However, the pattern of variation for this gene differs between the two populations. Our results indicate that several key HIF-regulatory and targeted genes are responsible for adaptation to high altitude in Andeans and Tibetans, and several different chromosomal regions are implicated in the putative response to selection. These data suggest a genetic role in high-altitude adaption and provide a basis for future genotype/phenotype association studies necessary to confirm the role of selection-nominated candidate genes and gene regions in adaptation to altitude. PMID:20838600

Breast cancer screening effect across breast density strata: A case-control study.

PubMed

van der Waal, Daniëlle; Ripping, Theodora M; Verbeek, André L M; Broeders, Mireille J M

2017-01-01

Breast cancer screening is known to reduce breast cancer mortality. A high breast density may affect this reduction. We assessed the effect of screening on breast cancer mortality in women with dense and fatty breasts separately. Analyses were performed within the Nijmegen (Dutch) screening programme (1975-2008), which invites women (aged 50-74 years) biennially. Performance measures were determined. Furthermore, a case-control study was performed for women having dense and women having fatty breasts. Breast density was assessed visually with a dichotomized Wolfe scale. Breast density data were available for cases. The prevalence of dense breasts among controls was estimated with age-specific rates from the general population. Sensitivity analyses were performed on these estimates. Screening performance was better in the fatty than in the dense group (sensitivity 75.7% vs 57.8%). The mortality reduction appeared to be smaller for women with dense breasts, with an odds ratio (OR) of 0.87 (95% CI 0.52-1.45) in the dense and 0.59 (95% CI 0.44-0.79) in the fatty group. We can conclude that high density results in lower screening performance and appears to be associated with a smaller mortality reduction. Breast density is thus a likely candidate for risk-stratified screening. More research is needed on the association between density and screening harms. © 2016 UICC.

Geographical and Geodemographic Connections between Different Types of Small Area as the Origins and Destinations of Migrants to Mid-Wales

ERIC Educational Resources Information Center

Walford, Nigel

2007-01-01

Exchanges of population between supposedly "urban" and "rural" spaces have occurred throughout history as people migrate between areas with relatively, densely and sparsely settled populations. However, comparatively little is known about whether the same small areas persistently contribute to the flow and what types of…

Possible Climate Change Influences on Continued Reduction of Dense Fog in Southern California

NASA Astrophysics Data System (ADS)

Ladochy, S.; Witiw, M.

2010-07-01

Dense fog appears to be decreasing in many parts of the world, especially in cities. An earlier study showed that dense fog (visibility < 400 m) was disappearing in the urban southern California area as well. Using hourly data from 1948 to the present, we looked at the relationship between fog events and contributing factors in the region along with trends over time. We showed that the decrease in dense fog events could be explained mainly by declining particulate levels, Pacific SSTs, and increased urban warming. Dense fog is most prevalent along the coast and decreases rapidly inland, so the influence of the Pacific should be large. In particular, the Pacific Decadal Oscillation (PDO) and the Southern Oscillation signals can be seen in fog frequencies as well as in the contributing factors. Results show a decrease in the occurrence of dense fog at two airports in close proximity to the Pacific Ocean, LAX and LGB. Occurrence of the frequency of low visibilities at these two locations was highly correlated with the phases of the PDO. While examining data from LAX, we saw a frequency of dense fog that reached over 300 hours in 1950, but occurrence was down to zero in 1997. Since 1997, there has been a bit of a recovery with both 2008 and 2009 recording over 30 hours of dense fog each. In the present study, we continue to examine the relationships that control the frequency of dense fog in coastal southern California. To remove urban influence, we also included Vandenberg Air Force Base, located in a relatively sparsely populated area. While particulates, urban heat island and Pacific SSTs are all contributing factors, we now speculate on the direct and indirect influences of climate change on continued decreases in dense fog. Case studies of local and regional dense fog in southern California point to the importance of strong, low inversions and to a lesser contributor, Santa Ana winds. Both are associated with large-scale atmospheric circulation patterns, which have changed markedly over the period of study.

Amazonian foods and implications for human biology.

PubMed

Dufour, Darna L; Piperata, Barbara A; Murrieta, Rui S S; Wilson, Warren M; Williams, Drake D

2016-07-01

Diets of subsistence-based Amazonian populations have been linked to local resources, but are changing with market penetration. To review the available data on traditional Amazonian foods and diets and evaluate their implications for human biology as a step toward understanding nutrition transitions in the region. This study used the Human Relations Area Files for information on the diets of Amerindian groups in the Amazon Basin from 1950 to the present, and used other published sources and the authors' own data. Data on food use was identified for only nine groups and dietary intake data for individuals in only three of the groups. A diet based on starchy staples (manioc and plantains) and fish, supplemented with a limited variety of other plant and animal foods, was found. Bitter manioc-based foods were associated with the consumption of cyanogens and fish with the consumption of mercury. Diets of adults appear to be adequate in energy and protein and low in fats. Children's diets were not well documented. Based on the limited available data, Amazonian diets are restricted in variety, but appear to be adequate in energy and protein for adults, but likely insufficiently nutrient-dense for children.

Evaluating Chemical Tracers as Indicators of Nitrate-Nitrogen Sources in Groundwater

NASA Astrophysics Data System (ADS)

Nitka, A.; DeVita, W.; McGinley, P.

2014-12-01

Groundwater nitrate-N concentrations greater than 3 mg/L usually indicate contamination from either agriculture or wastewater disposal. The objective of this study was to use chemical indicators to reliably determine sources of nitrate contamination in private wells. We developed an analytical method for a suite of human waste indicators. The selection of chemical tracers was based on their likely occurrence and mobility in groundwater. The suite included artificial sweeteners, pharmaceuticals and personal care products. Pesticide metabolites were used to identify contamination due to agricultural practices. A densely populated suburban area with adjacent agricultural land was selected. Eighteen private water supply wells and six monitoring wells were analyzed for nitrate-N and contaminant indicators. All of the wells with nitrate concentrations greater than 3 mg/L had at least one chemical indicator. Of these, 90% had two or more human waste contaminants, 40% had pesticide metabolites, and 30% had both. Of the wells with nitrate greater than 10 mg/L, 80% had two or more human waste indicators, 70% had pesticide metabolites, and 50% had both. The results of this research will help direct land management decisions and selection of appropriate water treatment options.

The human gut resistome.

PubMed

van Schaik, Willem

2015-06-05

In recent decades, the emergence and spread of antibiotic resistance among bacterial pathogens has become a major threat to public health. Bacteria can acquire antibiotic resistance genes by the mobilization and transfer of resistance genes from a donor strain. The human gut contains a densely populated microbial ecosystem, termed the gut microbiota, which offers ample opportunities for the horizontal transfer of genetic material, including antibiotic resistance genes. Recent technological advances allow microbiota-wide studies into the diversity and dynamics of the antibiotic resistance genes that are harboured by the gut microbiota ('the gut resistome'). Genes conferring resistance to antibiotics are ubiquitously present among the gut microbiota of humans and most resistance genes are harboured by strictly anaerobic gut commensals. The horizontal transfer of genetic material, including antibiotic resistance genes, through conjugation and transduction is a frequent event in the gut microbiota, but mostly involves non-pathogenic gut commensals as these dominate the microbiota of healthy individuals. Resistance gene transfer from commensals to gut-dwelling opportunistic pathogens appears to be a relatively rare event but may contribute to the emergence of multi-drug resistant strains, as is illustrated by the vancomycin resistance determinants that are shared by anaerobic gut commensals and the nosocomial pathogen Enterococcus faecium.

The human gut resistome

PubMed Central

van Schaik, Willem

2015-01-01

In recent decades, the emergence and spread of antibiotic resistance among bacterial pathogens has become a major threat to public health. Bacteria can acquire antibiotic resistance genes by the mobilization and transfer of resistance genes from a donor strain. The human gut contains a densely populated microbial ecosystem, termed the gut microbiota, which offers ample opportunities for the horizontal transfer of genetic material, including antibiotic resistance genes. Recent technological advances allow microbiota-wide studies into the diversity and dynamics of the antibiotic resistance genes that are harboured by the gut microbiota (‘the gut resistome’). Genes conferring resistance to antibiotics are ubiquitously present among the gut microbiota of humans and most resistance genes are harboured by strictly anaerobic gut commensals. The horizontal transfer of genetic material, including antibiotic resistance genes, through conjugation and transduction is a frequent event in the gut microbiota, but mostly involves non-pathogenic gut commensals as these dominate the microbiota of healthy individuals. Resistance gene transfer from commensals to gut-dwelling opportunistic pathogens appears to be a relatively rare event but may contribute to the emergence of multi-drug resistant strains, as is illustrated by the vancomycin resistance determinants that are shared by anaerobic gut commensals and the nosocomial pathogen Enterococcus faecium. PMID:25918444

Statistical analysis of suprathermal electron drivers at 67P/Churyumov-Gerasimenko

NASA Astrophysics Data System (ADS)

Broiles, Thomas W.; Burch, J. L.; Chae, K.; Clark, G.; Cravens, T. E.; Eriksson, A.; Fuselier, S. A.; Frahm, R. A.; Gasc, S.; Goldstein, R.; Henri, P.; Koenders, C.; Livadiotis, G.; Mandt, K. E.; Mokashi, P.; Nemeth, Z.; Odelstad, E.; Rubin, M.; Samara, M.

2016-11-01

We use observations from the Ion and Electron Sensor (IES) on board the Rosetta spacecraft to study the relationship between the cometary suprathermal electrons and the drivers that affect their density and temperature. We fit the IES electron observations with the summation of two kappa distributions, which we characterize as a dense and warm population (˜10 cm-3 and ˜16 eV) and a rarefied and hot population (˜0.01 cm-3 and ˜43 eV). The parameters of our fitting technique determine the populations' density, temperature, and invariant kappa index. We focus our analysis on the warm population to determine its origin by comparing the density and temperature with the neutral density and magnetic field strength. We find that the warm electron population is actually two separate sub-populations: electron distributions with temperatures above 8.6 eV and electron distributions with temperatures below 8.6 eV. The two sub-populations have different relationships between their density and temperature. Moreover, the two sub-populations are affected by different drivers. The hotter sub-population temperature is strongly correlated with neutral density, while the cooler sub-population is unaffected by neutral density and is only weakly correlated with magnetic field strength. We suggest that the population with temperatures above 8.6 eV is being heated by lower hybrid waves driven by counterstreaming solar wind protons and newly formed, cometary ions created in localized, dense neutral streams. To the best of our knowledge, this represents the first observations of cometary electrons heated through wave-particle interactions.

Interactions among human behavior, social networks, and societal infrastructures: A Case Study in Computational Epidemiology

NASA Astrophysics Data System (ADS)

Barrett, Christopher L.; Bisset, Keith; Chen, Jiangzhuo; Eubank, Stephen; Lewis, Bryan; Kumar, V. S. Anil; Marathe, Madhav V.; Mortveit, Henning S.

Human behavior, social networks, and the civil infrastructures are closely intertwined. Understanding their co-evolution is critical for designing public policies and decision support for disaster planning. For example, human behaviors and day to day activities of individuals create dense social interactions that are characteristic of modern urban societies. These dense social networks provide a perfect fabric for fast, uncontrolled disease propagation. Conversely, people’s behavior in response to public policies and their perception of how the crisis is unfolding as a result of disease outbreak can dramatically alter the normally stable social interactions. Effective planning and response strategies must take these complicated interactions into account. In this chapter, we describe a computer simulation based approach to study these issues using public health and computational epidemiology as an illustrative example. We also formulate game-theoretic and stochastic optimization problems that capture many of the problems that we study empirically.

Method and apparatus for controlled size distribution of gel microspheres formed from aqueous dispersions

DOEpatents

Ryon, Allen D.; Haas, Paul A.; Vavruska, John S.

1984-01-01

The present invention is directed to a method and apparatus for making a population of dense, closely size-controlled microspheres by sol-gel procedures wherein said microspheres are characterized by a significant percentage of said population being within a predetermined, relatively narrow size range. Microsphere populations thus provided are useful in vibratory-packed processes for nuclear fuels to be irradiated in LWR- and FBR-type nuclear reactors.

The Effects of Stellar Dynamics on the Evolution of Young, Dense Stellar Systems

NASA Astrophysics Data System (ADS)

Belkus, H.; van Bever, J.; Vanbeveren, D.

In this paper, we report on first results of a project in Brussels in which we study the effects of stellar dynamics on the evolution of young dense stellar systems using 3 decades of expertise in massive-star evolution and our population (number and spectral) synthesis code. We highlight an unconventionally formed object scenario (UFO-scenario) for Wolf Rayet binaries and study the effects of a luminous blue variable-type instability wind mass-loss formalism on the formation of intermediate-mass black holes.

Report to Congress : nonmilitary helicopter urban noise study

DOT National Transportation Integrated Search

2004-12-31

In response to public concerns about nonmilitary helicopter noise impact on densely populated : communities, the United States Congress directed the Secretary of Transportation to investigate : and develop recommendations on reducing helicopter noise...

Numerical Relativity Simulations of Compact Binary Populations in Dense Stellar Environments

NASA Astrophysics Data System (ADS)

Glennon, Derek Ray; Huerta, Eliu; Allen, Gabrielle; Haas, Roland; Seidel, Edward; NCSA Gravity Group

2018-01-01

We present a catalog of numerical relativity simulations that describe binary black hole mergers on eccentric orbits. These simulations have been obtained with the open source, Einstein Toolkit numerical relativity software, using the Blue Waters supercomputer. We use this catalog to quantify observables, such as the mass and spin of black holes formed by binary black hole mergers, as a function of eccentricity. This study is the first of its kind in the literature to quantify these astrophysical observables for binary black hole mergers with mass-ratios q<6, and eccentricities e<0.2. This study is an important step in understanding the properties of eccentric binary black hole mergers, and informs the use of gravitational wave observations to confirm or rule out the existence of compact binary populations in dense stellar environments.

A genomic portrait of haplotype diversity and signatures of selection in indigenous southern African populations.

PubMed

Chimusa, Emile R; Meintjies, Ayton; Tchanga, Milaine; Mulder, Nicola; Seoighe, Cathal; Seioghe, Cathal; Soodyall, Himla; Ramesar, Rajkumar

2015-03-01

We report a study of genome-wide, dense SNP (∼ 900K) and copy number polymorphism data of indigenous southern Africans. We demonstrate the genetic contribution to southern and eastern African populations, which involved admixture between indigenous San, Niger-Congo-speaking and populations of Eurasian ancestry. This finding illustrates the need to account for stratification in genome-wide association studies, and that admixture mapping would likely be a successful approach in these populations. We developed a strategy to detect the signature of selection prior to and following putative admixture events. Several genomic regions show an unusual excess of Niger-Kordofanian, and unusual deficiency of both San and Eurasian ancestry, which were considered the footprints of selection after population admixture. Several SNPs with strong allele frequency differences were observed predominantly between the admixed indigenous southern African populations, and their ancestral Eurasian populations. Interestingly, many candidate genes, which were identified within the genomic regions showing signals for selection, were associated with southern African-specific high-risk, mostly communicable diseases, such as malaria, influenza, tuberculosis, and human immunodeficiency virus/AIDs. This observation suggests a potentially important role that these genes might have played in adapting to the environment. Additionally, our analyses of haplotype structure, linkage disequilibrium, recombination, copy number variation and genome-wide admixture highlight, and support the unique position of San relative to both African and non-African populations. This study contributes to a better understanding of population ancestry and selection in south-eastern African populations; and the data and results obtained will support research into the genetic contributions to infectious as well as non-communicable diseases in the region.

A Genomic Portrait of Haplotype Diversity and Signatures of Selection in Indigenous Southern African Populations

PubMed Central

Chimusa, Emile R.; Meintjies, Ayton; Tchanga, Milaine; Mulder, Nicola; Seoighe, Cathal; Soodyall, Himla; Ramesar, Rajkumar

2015-01-01

We report a study of genome-wide, dense SNP (∼900K) and copy number polymorphism data of indigenous southern Africans. We demonstrate the genetic contribution to southern and eastern African populations, which involved admixture between indigenous San, Niger-Congo-speaking and populations of Eurasian ancestry. This finding illustrates the need to account for stratification in genome-wide association studies, and that admixture mapping would likely be a successful approach in these populations. We developed a strategy to detect the signature of selection prior to and following putative admixture events. Several genomic regions show an unusual excess of Niger-Kordofanian, and unusual deficiency of both San and Eurasian ancestry, which were considered the footprints of selection after population admixture. Several SNPs with strong allele frequency differences were observed predominantly between the admixed indigenous southern African populations, and their ancestral Eurasian populations. Interestingly, many candidate genes, which were identified within the genomic regions showing signals for selection, were associated with southern African-specific high-risk, mostly communicable diseases, such as malaria, influenza, tuberculosis, and human immunodeficiency virus/AIDs. This observation suggests a potentially important role that these genes might have played in adapting to the environment. Additionally, our analyses of haplotype structure, linkage disequilibrium, recombination, copy number variation and genome-wide admixture highlight, and support the unique position of San relative to both African and non-African populations. This study contributes to a better understanding of population ancestry and selection in south-eastern African populations; and the data and results obtained will support research into the genetic contributions to infectious as well as non-communicable diseases in the region. PMID:25811879

Personalised chemotherapy based on tumour marker decline in poor prognosis germ-cell tumours (GETUG 13): a phase 3, multicentre, randomised trial.

PubMed

Fizazi, Karim; Pagliaro, Lance; Laplanche, Agnes; Fléchon, Aude; Mardiak, Josef; Geoffrois, Lionnel; Kerbrat, Pierre; Chevreau, Christine; Delva, Remy; Rolland, Frederic; Theodore, Christine; Roubaud, Guilhem; Gravis, Gwenaëlle; Eymard, Jean-Christophe; Malhaire, Jean-Pierre; Linassier, Claude; Habibian, Muriel; Martin, Anne-Laure; Journeau, Florence; Reckova, Maria; Logothetis, Christopher; Culine, Stephane

2014-12-01

Poor prognosis germ-cell tumours are only cured in about half of patients. We aimed to assess whether treatment intensification based on an early tumour marker decline will improve progression-free survival for patients with germ-cell tumours. In this phase 3, multicentre, randomised trial, patients were enrolled from France (20 centres), USA (one centre), and Slovakia (one centre). Patients were eligible if they were older than 16 years, had evidence of testicular, retroperitoneal, or mediastinal non-seminomatous germ cell tumours based on histological findings or clinical evidence and highly elevated serum human chorionic gonadotropin or alfa-fetoprotein concentrations that matched International Germ Cell Cancer Consensus Group poor prognosis criteria. After one cycle of BEP (intravenous cisplatin [20 mg/m(2) per day for 5 days], etoposide [100 mg/m(2) per day for 5 days], and intramuscular or intravenous bleomycin [30 mg per day on days 1, 8, and 15]), patients' human chorionic gonadotropin and alfa-fetoprotein concentrations were measured at day 18-21. Patients with a favourable decline in human chorionic gonadotropin and alfa-fetoprotein continued BEP (Fav-BEP group) for 3 additonal cycles, whereas patients with an unfavourable decline were randomly assigned (1:1) to receive either BEP (Unfav-BEP group) or a dose-dense regimen (Unfav-dose-dense group), consisting of intravenous paclitaxel (175 mg/m(2) over 3 h on day 1) before BEP plus intravenous oxaliplatin (130 mg/m(2) over 3 h on day 10; two cycles), followed by intravenous cisplatin (100 mg/m(2) over 2 h on day 1), intravenous ifosfamide (2 g/m(2) over 3 h on days 10, 12, and 14), plus mesna (500 mg/m(2) at 0, 3, 7 and 11 h), and bleomycin (25 units per day, by continuous infusion for 5 days on days 10-14; two cycles), with granulocyte-colony stimulating factor (lenograstim) support. Centrally blocked computer-generated randomisation stratified by centre was used. The primary endpoint was progression-free survival and the efficacy analysis was done in the intention-to-treat population. The planned trial accrual was completed in May, 2012, and follow-up is ongoing. This study is registered with ClinicalTrials.gov, number NCT00104676. Between Nov 28, 2003, and May 16, 2012, 263 patients were enrolled and 254 were available for tumour marker assessment. Of these 51 (20%) had a favourable marker assessment, and 203 (80%) had an unfavourable tumour marker decline; 105 were randomly assigned to the Unfav-dose-dense group and 98 to the Unfav-BEP group. 3-year progression-free survival was 59% (95% CI 49-68) in the Unfav-dose-dense group versus 48% (38-59) in the Unfav-BEP group (HR 0·66, 95% CI 0·44-1·00, p=0·05). 3-year progression-free survival was 70% (95% CI 57-81) in the Fav-BEP group (HR 0·66, 95% CI 0·49-0·88, p=0·01 for progression-free survival compared with the Unfav-BEP group). More grade 3-4 neurotoxic events (seven [7%] vs one [1%]) and haematotoxic events occurred in the Unfav-dose-dense group compared with in the Unfav-BEP group; there was no difference in grade 1-2 febrile neutropenia (18 [17%] vs 18 [18%]) or toxic deaths (one [1%] in both groups). Salvage high-dose chemotherapy plus a stem-cell transplant was required in six (6%) patients in the Unfav-dose-dense group and 16 (16%) in the Unfav-BEP group. Personalised treatment with chemotherapy intensification reduces the risk of progression or death in patients with poor prognosis germ-cell tumours and an unfavourable tumour marker decline. Institut National du Cancer (Programme Hospitalier de Recherche Clinique). Copyright © 2014 Elsevier Ltd. All rights reserved.

Sea otters in the northern Pacific Ocean

USGS Publications Warehouse

Bodkin, James L.; Jameson, Ronald J.; Estes, James A.; LaRoe, Edward T.; Farris, Gaye S.; Puckett, Catherine E.; Doran, Peter D.; Mac, Michael J.

1995-01-01

About 250 years ago sea otters (Enhydra lutris) were distributed continuously from central Baja California, north and west along the Pacific Rim to Machatka Peninsula in Russia, and south along the Kuril Island to northern Japan (Kenyon 1969; Fig. 1a). Several hundred thousand sea otters may have occurred in the north Pacific region when commercial hunting began in the 18th century (Riedman and Estes 1990).At least two attributes of the sea otter have influenced humans, likely for as long as they have resided together along the coast of the north Pacific Ocean. First, sea otters rely on a dense fur, among the finest in the world, for insulation in the cold waters of the Pacific Ocean. The demand for sea otter fur led to their near extinction in the 19th century. The fur harvest, begun about 1740 and halted by international treaty in 1911, left surviving colonies, each likely numbering less than a few hundred animals, in California, south-central Alaska, and the Aleutian, Medney, and Kuril Islands (Fig. 1a). These individuals provided the nucleus for the recovery of the species. Today more than 100,000 sea otters occur throughout about 75% of their original range (fig. 1b). Immigration has resulted in near-complete occupation of the Aleutian and Kuril archipelagos and the Alaska peninsula. Successful translocations have resulted in viable populations in southeast Alaska, Washington, and British Columbia. Large amounts of unoccupied habitat remain along the coasts of Russia, Canada, the United States, and Mexico.The second potential source of conflict between sea otters and humans is that sea otters prey on and often limit some benthic invertebrate populations. Because some of these invertebrates are aso used by humans (Estes and VanBlaricom 1985), human perceptions about the effects of sea otter foraging on invertebrates sometimes differ. By limiting populations of herbivorous invertebrates (e.g., sea urchins [Echinoidea]) otters help maintain the integrity of kelp forest communities. At the same time, sea otter predation on other marine invertebrates can lead to direct competition with humans for resources. These interactions add complex dimensions to the conservation and management of sea otters, in large part because of wide-ranging social, ecological, and economic consequences of sea otter foraging.Long-term data on abundance and distribution are available for relatively few sea otter populations. Here we summarize such data from three populations: Being Island, Russia; Prince William Sound, Alaska; and Olympic Peninsula, Washington. The Bering Island population resulted from natural emigration and represents complete recovery. Prince William Sounds represents near recovery of a remnant population, whereas the Washington population was established via translocations from Alaska and is just beginning to recover. We will compare growth rates and current status among these populations. Because of its unique status and growth characteristics, the California sea otter is not treated in this article.

Contents of heavy metals in urban parks and university campuses

NASA Astrophysics Data System (ADS)

Zhang, Yong; Chen, Qian

2018-01-01

Because the city park has become an important place for people's daily leisure, and the university campus is one of the most densely populated areas of the city, their environmental pollution is critical for the health and safety of the residents. In this paper, two kinds of evaluation methods were used to evaluate the content of Cu, Zn, As and Pb in soils of city parks and university campus in Xiangtan. The results showed that only Juhuatang Park was a non-polluted area, and the other 7 sampling sites were lightly polluted; Analysis shows the heavy metal contents of soil in city parks are closely related to vehicle emissions, agriculture and irrigation, combustion of household waste, living area and commercial shops, the use of fossil fuels, industrial waste gas and waste residue and other human activities.

Production and supply of high-quality food protein for human consumption: sustainability, challenges, and innovations.

PubMed

Wu, Guoyao; Fanzo, Jessica; Miller, Dennis D; Pingali, Prabhu; Post, Mark; Steiner, Jean L; Thalacker-Mercer, Anna E

2014-08-01

The Food and Agriculture Organization of the United Nations estimates that 843 million people worldwide are hungry and a greater number suffer from nutrient deficiencies. Approximately one billion people have inadequate protein intake. The challenge of preventing hunger and malnutrition will become even greater as the global population grows from the current 7.2 billion people to 9.6 billion by 2050. With increases in income, population, and demand for more nutrient-dense foods, global meat production is projected to increase by 206 million tons per year during the next 35 years. These changes in population and dietary practices have led to a tremendous rise in the demand for food protein, especially animal-source protein. Consuming the required amounts of protein is fundamental to human growth and health. Protein needs can be met through intakes of animal and plant-source foods. Increased consumption of food proteins is associated with increased greenhouse gas emissions and overutilization of water. Consequently, concerns exist regarding impacts of agricultural production, processing and distribution of food protein on the environment, ecosystem, and sustainability. To address these challenging issues, the New York Academy of Sciences organized the conference "Frontiers in Agricultural Sustainability: Studying the Protein Supply Chain to Improve Dietary Quality" to explore sustainable innovations in food science and programming aimed at producing the required quality and quantity of protein through improved supply chains worldwide. This report provides an extensive discussion of these issues and summaries of the presentations from the conference. © 2014 New York Academy of Sciences.

Carpinus tibetana (Betulaceae), a new species from southeast Tibet, China

PubMed Central

Lu, Zhiqiang; Li, Ying; Yang, Xiaoyue; Liu, Jianquan

2018-01-01

Abstract A new species Carpinus tibetana Z. Qiang Lu & J. Quan Liu from southeast Tibet is described and illustrated. The specimens of this new species were previously identified and placed under C. monbeigiana Hand.-Mazz. or C. mollicoma Hu. However, the specimens from southeast Tibet differ from those of C. monbeigiana from other regions with more lateral veins (19–24 vs 14–18) on each side of the midvein and dense pubescence on the abaxial leaf surface, while from those of C. mollicoma from other regions differ by nutlet with dense resinous glands and glabrous or sparsely villous at apex. Principal Component Analyses based on morphometric characters recognise the Tibetan populations as a separate group. Nuclear ribosomal ITS sequence variations show stable and distinct genetic divergences between the Tibetan populations and C. monbeigiana or C. mollicoma by two or three fixed nucleotide mutations. Phylogenetic analysis also identified three respective genetic clusters and the C. mollicoma cluster diverged early. In addition, the Tibetan populations show a disjunct geographic isolation from the other two species. Therefore, C. tibetana, based on the Tibetan populations, is here erected as a new species, distinctly different from C. monbeigiana and C. mollicoma. PMID:29750069

Carpinus tibetana (Betulaceae), a new species from southeast Tibet, China.

PubMed

Lu, Zhiqiang; Li, Ying; Yang, Xiaoyue; Liu, Jianquan

2018-01-01

A new species Carpinus tibetana Z. Qiang Lu & J. Quan Liu from southeast Tibet is described and illustrated. The specimens of this new species were previously identified and placed under C. monbeigiana Hand.-Mazz. or C. mollicoma Hu. However, the specimens from southeast Tibet differ from those of C. monbeigiana from other regions with more lateral veins (19-24 vs 14-18) on each side of the midvein and dense pubescence on the abaxial leaf surface, while from those of C. mollicoma from other regions differ by nutlet with dense resinous glands and glabrous or sparsely villous at apex. Principal Component Analyses based on morphometric characters recognise the Tibetan populations as a separate group. Nuclear ribosomal ITS sequence variations show stable and distinct genetic divergences between the Tibetan populations and C. monbeigiana or C. mollicoma by two or three fixed nucleotide mutations. Phylogenetic analysis also identified three respective genetic clusters and the C. mollicoma cluster diverged early. In addition, the Tibetan populations show a disjunct geographic isolation from the other two species. Therefore, C. tibetana , based on the Tibetan populations, is here erected as a new species, distinctly different from C. monbeigiana and C. mollicoma .

Mitochondrial DNA diversity of the Amerindian populations living in the Andean Piedmont of Bolivia: Chimane, Moseten, Aymara and Quechua.

PubMed

Corella, Alfons; Bert, Francesc; Pérez-Pérez, Alejandro; Gené, Manel; Turbón, Daniel

2007-01-01

Chimane, Moseten Aymara and Quechua are Amerindian populations living in the Bolivian Piedmont, a characteristic ecoregion between the eastern slope of the Andean mountains and the Amazonian Llanos de Moxos. In both neighbouring areas, dense and complex societies have developed over the centuries. The Piedmont area is especially interesting from a human peopling perspective since there is no clear evidence regarding the genetic influence and peculiarities of these populations. This land has been used extensively as a territory of economic and cultural exchange between the Andes and Amazonia, however Chimane and Moseten populations have been sufficiently isolated from their neighbour groups to be recognized as distinct populations. Genetic information suggests that evolutionary processes, such as genetic drift, natural selection and genetic admixture have formed the history of the Piedmont populations. The objective of this study is to characterize the genetic diversity of the Piedmont populations, analysing the sequence variability of the HVR-I control region in the mitochondrial DNA (mtDNA). Haplogroup mtDNA data available from the whole of Central and South America were utilized to determine the relationship of the Piedmont populations with other Amerindian populations. Hair pulls were obtained in situ, and DNA from non-related individuals was extracted using a standard Chelex 100 method. A 401 bp DNA fragment of HVR-I region was amplified using standard procedures. Two independent 401 and 328 bp DNA fragments were sequenced separately for each sample. The sequence analyses included mismatch distribution and mean pairwise differences, median network analyses, AMOVA and principal component analyses. The genetic diversity of DNA sequences was measured and compared with other South Amerindian populations. The genetic diversity of 401 nucleotide mtDNA sequences, in the hypervariable Control Region, from positions 16 000-16 400, was characterized in a sample of 46 Amerindians living in the Piedmont area in the Beni Department of Bolivia. The results obtained indicate that the genetic diversity in the area is higher than that observed in other American groups living in much larger areas and despite the reduced size of the studied area the human groups analysed show high levels of inter-group variability. In addition, results show that Amerindian populations living in the Piedmont are genetically more related to those in the Andean than in the Amazonian populations.

High-resolution atmospheric emission inventory of the argentine energy sector. Comparison with edgar global emission database.

PubMed

Puliafito, S Enrique; Allende, David G; Castesana, Paula S; Ruggeri, Maria F

2017-12-01

This study presents a 2014 high-resolution spatially disaggregated emission inventory (0.025° × 0.025° horizontal resolution), of the main activities in the energy sector in Argentina. The sub-sectors considered are public generation of electricity, oil refineries, cement production, transport (maritime, air, rail and road), residential and commercial. The following pollutants were included: greenhouse gases (CO 2 , CH 4 , N 2 O), ozone precursors (CO, NOx, VOC) and other specific air quality indicators such as SO 2 , PM10, and PM2.5. This work could contribute to a better geographical allocation of the pollutant sources through census based population maps. Considering the sources of greenhouse gas emissions, the total amount is 144 Tg CO2eq, from which the transportation sector emits 57.8 Tg (40%); followed by electricity generation, with 40.9 Tg (28%); residential + commercial, with 31.24 Tg (22%); and cement and refinery production, with 14.3 Tg (10%). This inventory shows that 49% of the total emissions occur in rural areas: 31% in rural areas of medium population density, 13% in intermediate urban areas and 7% in densely populated urban areas. However, if emissions are analyzed by extension (per square km), the largest impact is observed in medium and densely populated urban areas, reaching more than 20.3 Gg per square km of greenhouse gases, 297 Mg/km 2 of ozone precursors gases and 11.5 Mg/km 2 of other air quality emissions. A comparison with the EDGAR global emission database shows that, although the total country emissions are similar for several sub sectors and pollutants, its spatial distribution is not applicable to Argentina. The road and residential transport emissions represented by EDGAR result in an overestimation of emissions in rural areas and an underestimation in urban areas, especially in more densely populated areas. EDGAR underestimates 60 Gg of methane emissions from road transport sector and fugitive emissions from refining activities.

Statistical power calculations for mixed pharmacokinetic study designs using a population approach.

PubMed

Kloprogge, Frank; Simpson, Julie A; Day, Nicholas P J; White, Nicholas J; Tarning, Joel

2014-09-01

Simultaneous modelling of dense and sparse pharmacokinetic data is possible with a population approach. To determine the number of individuals required to detect the effect of a covariate, simulation-based power calculation methodologies can be employed. The Monte Carlo Mapped Power method (a simulation-based power calculation methodology using the likelihood ratio test) was extended in the current study to perform sample size calculations for mixed pharmacokinetic studies (i.e. both sparse and dense data collection). A workflow guiding an easy and straightforward pharmacokinetic study design, considering also the cost-effectiveness of alternative study designs, was used in this analysis. Initially, data were simulated for a hypothetical drug and then for the anti-malarial drug, dihydroartemisinin. Two datasets (sampling design A: dense; sampling design B: sparse) were simulated using a pharmacokinetic model that included a binary covariate effect and subsequently re-estimated using (1) the same model and (2) a model not including the covariate effect in NONMEM 7.2. Power calculations were performed for varying numbers of patients with sampling designs A and B. Study designs with statistical power >80% were selected and further evaluated for cost-effectiveness. The simulation studies of the hypothetical drug and the anti-malarial drug dihydroartemisinin demonstrated that the simulation-based power calculation methodology, based on the Monte Carlo Mapped Power method, can be utilised to evaluate and determine the sample size of mixed (part sparsely and part densely sampled) study designs. The developed method can contribute to the design of robust and efficient pharmacokinetic studies.

Facilitation in Caribbean coral reefs: high densities of staghorn coral foster greater coral condition and reef fish composition.

PubMed

Huntington, Brittany E; Miller, Margaret W; Pausch, Rachel; Richter, Lee

2017-05-01

Recovery of the threatened staghorn coral (Acropora cervicornis) is posited to play a key role in Caribbean reef resilience. At four Caribbean locations (including one restored and three extant populations), we quantified characteristics of contemporary staghorn coral across increasing conspecific densities, and investigated a hypothesis of facilitation between staghorn coral and reef fishes. High staghorn densities in the Dry Tortugas exhibited significantly less partial mortality, higher branch growth, and supported greater fish abundances compared to lower densities within the same population. In contrast, partial mortality, branch growth, and fish community composition did not vary with staghorn density at the three other study locations where staghorn densities were lower overall. This suggests that density-dependent effects between the coral and fish community may only manifest at high staghorn densities. We then evaluated one facilitative mechanism for such density-dependence, whereby abundant fishes sheltering in dense staghorn aggregations deliver nutrients back to the coral, fueling faster coral growth, thereby creating more fish habitat. Indeed, dense staghorn aggregations within the Dry Tortugas exhibited significantly higher growth rates, tissue nitrogen, and zooxanthellae densities than sparse aggregations. Similarly, higher tissue nitrogen was induced in a macroalgae bioassay outplanted into the same dense and sparse aggregations, confirming greater bioavailability of nutrients at high staghorn densities. Our findings inform staghorn restoration efforts, suggesting that the most effective targets may be higher coral densities than previously thought. These coral-dense aggregations may reap the benefits of positive facilitation between the staghorn and fish community, favoring the growth and survivorship of this threatened species.

Insights from past millennia into climatic impacts on human health and survival

PubMed Central

McMichael, Anthony J.

2012-01-01

Climate change poses threats to human health, safety, and survival via weather extremes and climatic impacts on food yields, fresh water, infectious diseases, conflict, and displacement. Paradoxically, these risks to health are neither widely nor fully recognized. Historical experiences of diverse societies experiencing climatic changes, spanning multicentury to single-year duration, provide insights into population health vulnerability—even though most climatic changes were considerably less than those anticipated this century and beyond. Historical experience indicates the following. (i) Long-term climate changes have often destabilized civilizations, typically via food shortages, consequent hunger, disease, and unrest. (ii) Medium-term climatic adversity has frequently caused similar health, social, and sometimes political consequences. (iii) Infectious disease epidemics have often occurred in association with briefer episodes of temperature shifts, food shortages, impoverishment, and social disruption. (iv) Societies have often learnt to cope (despite hardship for some groups) with recurring shorter-term (decadal to multiyear) regional climatic cycles (e.g., El Niño Southern Oscillation)—except when extreme phases occur. (v) The drought–famine–starvation nexus has been the main, recurring, serious threat to health. Warming this century is not only likely to greatly exceed the Holocene's natural multidecadal temperature fluctuations but to occur faster. Along with greater climatic variability, models project an increased geographic range and severity of droughts. Modern societies, although larger, better resourced, and more interconnected than past societies, are less flexible, more infrastructure-dependent, densely populated, and hence are vulnerable. Adverse historical climate-related health experiences underscore the case for abating human-induced climate change. PMID:22315419

Blood lead levels of wild Steller's eiders (Polysticta stelleri) and black scoters (Melanitta nigra) in Alaska using a portable blood lead analyzer

USGS Publications Warehouse

Brown, Corrine S.; Luebbert, Joanne; Mulcahy, Daniel M.; Schamber, Jason L.; Rosenberg, Daniel H.

2006-01-01

Sea duck populations are declining in Alaska. The reasons for the decline are not known; environmental lead exposure is one suspected cause. Thirty wild Steller's eider ducks (Polysticta stelleri) and 40 wild black scoter ducks (Melanitta nigra) were tested for blood lead levels using a portable blood lead analyzer (LeadCare; ESA, Inc., Chelmsford, Massachusetts 01824, USA). Sixty-seven and one-tenth percent of the sea ducks had undetectable blood lead levels, 30.0% had values indicating normal or background lead exposure, and 2.9% had values indicating lead exposure. None of the birds had values indicating lead toxicity, and no birds demonstrated clinical signs of toxicity. Birds in areas with higher human population density had higher blood lead levels than those in less densely populated areas. This is the first time a portable blood lead analyzer has been utilized with sea ducks in a field setting. Because it provides immediate results, it is valuable as a screening tool for investigators carrying out surgical procedures on birds in the field as well as establishing baseline blood lead data on sea ducks. Lead exposure does occur in wild sea ducks, and the study indicates that additional research is needed in order to determine the role environmental lead plays in declining sea duck populations.

CSF1R+ Macrophages Sustain Pancreatic Tumor Growth through T Cell Suppression and Maintenance of Key Gene Programs that Define the Squamous Subtype.

PubMed

Candido, Juliana B; Morton, Jennifer P; Bailey, Peter; Campbell, Andrew D; Karim, Saadia A; Jamieson, Thomas; Lapienyte, Laura; Gopinathan, Aarthi; Clark, William; McGhee, Ewan J; Wang, Jun; Escorcio-Correia, Monica; Zollinger, Raphael; Roshani, Rozita; Drew, Lisa; Rishi, Loveena; Arkell, Rebecca; Evans, T R Jeffry; Nixon, Colin; Jodrell, Duncan I; Wilkinson, Robert W; Biankin, Andrew V; Barry, Simon T; Balkwill, Frances R; Sansom, Owen J

2018-05-01

Pancreatic ductal adenocarcinoma (PDAC) is resistant to most therapies including single-agent immunotherapy and has a dense desmoplastic stroma, and most patients present with advanced metastatic disease. We reveal that macrophages are the dominant leukocyte population both in human PDAC stroma and autochthonous models, with an important functional contribution to the squamous subtype of human PDAC. We targeted macrophages in a genetic PDAC model using AZD7507, a potent selective inhibitor of CSF1R. AZD7507 caused shrinkage of established tumors and increased mouse survival in this difficult-to-treat model. Malignant cell proliferation diminished, with increased cell death and an enhanced T cell immune response. Loss of macrophages rewired other features of the TME, with global changes in gene expression akin to switching PDAC subtypes. These changes were markedly different to those elicited when neutrophils were targeted via CXCR2. These results suggest targeting the myeloid cell axis may be particularly efficacious in PDAC, especially with CSF1R inhibitors. Copyright © 2018 The Authors. Published by Elsevier Inc. All rights reserved.

On the importance of considering disease subtypes: Earliest detection of a parosteal osteosarcoma? Differential diagnosis of an osteosarcoma in an Anglo-Saxon female.

PubMed

Ferrante di Ruffano, Lavinia; Waldron, Tony

2016-12-30

A case of potentially dedifferentiated parosteal osteosarcoma was found in the proximal humerus of an adult female buried in the late Anglo-Saxon cemetery of Cherry Hinton, Cambridgeshire, UK. Key features include a large, dense, lobulated mass attached to the medial metaphysis of the proximal humerus by a broad-based attachment, accompanied by cortical destruction and widespread spiculated periosteal reaction. Radiographic images confirm medullary involvement, lack of continuity between the cortex and external mass, a radiolucent cleavage plane and possible radiolucent zones within the bony masses. Differential diagnoses considered include osteochondroma, myositis ossificans, fracture callus, as well as the primary malignancies of osteosarcoma and chondrosarcoma, and their various subtypes. The macroscopic and radiographic analysis of the tumor is described and discussed within clinical and paleopathological contexts. One of only 19 uncontested examples of osteosarcoma from past human populations, most of which remain unconfirmed, this case represents what we believe to be the earliest, and probably singular, bioarcheological example of parosteal osteosarcoma in human history. Crown Copyright © 2016. Published by Elsevier Inc. All rights reserved.

Dynamic Balance of Excitation and Inhibition in Human and Monkey Neocortex

NASA Astrophysics Data System (ADS)

Dehghani, Nima; Peyrache, Adrien; Telenczuk, Bartosz; Le van Quyen, Michel; Halgren, Eric; Cash, Sydney S.; Hatsopoulos, Nicholas G.; Destexhe, Alain

2016-03-01

Balance of excitation and inhibition is a fundamental feature of in vivo network activity and is important for its computations. However, its presence in the neocortex of higher mammals is not well established. We investigated the dynamics of excitation and inhibition using dense multielectrode recordings in humans and monkeys. We found that in all states of the wake-sleep cycle, excitatory and inhibitory ensembles are well balanced, and co-fluctuate with slight instantaneous deviations from perfect balance, mostly in slow-wave sleep. Remarkably, these correlated fluctuations are seen for many different temporal scales. The similarity of these computational features with a network model of self-generated balanced states suggests that such balanced activity is essentially generated by recurrent activity in the local network and is not due to external inputs. Finally, we find that this balance breaks down during seizures, where the temporal correlation of excitatory and inhibitory populations is disrupted. These results show that balanced activity is a feature of normal brain activity, and break down of the balance could be an important factor to define pathological states.

Intestinal Helminths of Wild Bonobos in Forest-Savanna Mosaic: Risk Assessment of Cross-Species Transmission with Local People in the Democratic Republic of the Congo.

PubMed

Narat, Victor; Guillot, Jacques; Pennec, Flora; Lafosse, Sophie; Grüner, Anne Charlotte; Simmen, Bruno; Bokika Ngawolo, Jean Christophe; Krief, Sabrina

2015-12-01

Phylogenetic and geographic proximities between humans and apes pose a risk of zoonotic transmission of pathogens. Bonobos (Pan paniscus) of the Bolobo Territory, Democratic Republic of the Congo, live in a fragmented forest-savanna mosaic setting, a marginal habitat for this species used to living in dense forests. Human activities in the forest have increased the risk of contacts between humans and bonobos. Over 21 months (September 2010-October 2013), we monitored intestinal parasites in bonobo (n = 273) and in human (n = 79) fecal samples to acquire data on bonobo parasitology and to assess the risk of intestinal helminth transmission between these hosts. Coproscopy, DNA amplification, and sequencing of stored dried feces and larvae were performed to identify helminths. Little difference was observed in intestinal parasites of bonobos in this dryer habitat compared to those living in dense forests. Although Strongylids, Enterobius sp., and Capillaria sp. were found in both humans and bonobos, the species were different between the hosts according to egg size or molecular data. Thus, no evidence of helminth transmission between humans and bonobos was found. However, because humans and this threatened species share the same habitat, it is essential to continue to monitor this risk.

A global analysis of human habitation on river deltas

NASA Astrophysics Data System (ADS)

Edmonds, Douglas; Caldwell, Rebecca; Baumgardner, Sarah; Paola, Chris; Roy, Samapriya; Nelson, Amelia; Nienhuis, Jaap

2017-04-01

River deltas are ideal sites for human habitation because of their fertile floodplains, easy access to the ocean, and abundant land. But anthropogenic and natural processes are causing deltas to sink, which increases the probability of coastal flooding and human exposure to risk. The full extent of the risk posed to humans is unclear because the number of people living on river deltas is unknown. Towards this end we mapped the locations and areas of all deltas in the world (n= 1813). Using Google Earth we identified all river mouths (≥ 50 m wide) on marine coastlines that are also connected to an upstream catchment. Rivers that split into two or more active or relict distributary channels, end in a depositional protrusion from the shoreline, or do both, are defined as deltas. The depositional protrusion and distributary channel network define the geomorphic area of each delta. We mark the position of the delta apex at the first bifurcation, or for a single channel delta at the intersection of the regional shoreline and the main channel. We mark three lateral extents, one on either side of the main channel at the maximum displacement of the depositional protrusion or the distributary network, and one on the most basinward position of the delta. We define delta area as the convex hull around these extent points and the delta apex. For each delta area polygon we extract elevation from the Shuttle Radar Topography Mission dataset and population count in years 2000, 2005, 2010, 2015, and 2020 from Gridded Population of the World, version 4. In total, deltas cover 0.56% of the total area of the world yet contain 4.1% of the world's population. The population on deltas has grown from 237 million in 2000 to projected values of 322 million in 2020. Deltaic population is growing at 1.59% per year, which outpaces the world growth rate of 1.11%. Additionally, population density is increasing with time from 322 people per km2 in year 2000 to projected values of 422 people per km2 in 2020. Of the 300 million people currently living on deltas, roughly 69% live below 10 meters elevation in the so-called low elevation coastal zone that is particularly susceptible to coastal flooding. Interestingly, the population in the low elevation coastal zone is unevenly distributed. The largest number of people, approximately 24%, live between 4 and 6 m elevation. This elevation range is also more densely populated at 580 people per km2, which is nearly 12 times the global mean of 47 people per km2. We consider these estimates to be a minimum given that we define delta area from the geomorphic footprint.

Observational Test of the Dayside Magnetopause Reconnection Rate

NASA Astrophysics Data System (ADS)

Wang, S.; Kistler, L. M.; Mouikis, C.

2014-12-01

In asymmetric reconnection, the reconnection rate (R) is expected to follow the Cassak-Shay formula with an aspect ratio of around 0.1. At the magnetopause, reconnection is asymmetric, with the dense shocked solar wind population on the magnetosheath side, and a normally hot and tenuous population on the magnetospheric side. However, the hot magnetospheric population can contain a significant O+ component that increases the mass density, and the magnetospheric population may also include a cold dense population of plasmaspheric origin. We perform a statistical study of 13 magnetopause reconnection events observed by Cluster to determine how the reconnection rate depends on these different populations. The events are mainly at high latitudes, due to the Cluster orbit. Our results show that the measured R generally follows the Cassak-Shay prediction when all populations are included. However, the predicted rate only considering the magnetosheath contribution also correlates well with the measured R. For individual events, cold ions can make a comparable contribution to the magnetosheath H+ when there are plasmaspheric drainage plumes; the contribution of the magnetospheric hot O+ can be up to ~30%. However, the variation of solar wind conditions has a larger effect on the variation in the reconnection rate. The aspect ratio does not vary systematically with the O+ content, and 0.1 is a reasonable estimation. The outflow velocity is around the hybrid Alfven speed, but there is not a strong correlation. This may be due to motion of the x-line, or effects of the magnetosheath shear flow.

Comparison of Drive Counts and Mark-Resight As Methods of Population Size Estimation of Highly Dense Sika Deer (Cervus nippon) Populations.

PubMed

Takeshita, Kazutaka; Ikeda, Takashi; Takahashi, Hiroshi; Yoshida, Tsuyoshi; Igota, Hiromasa; Matsuura, Yukiko; Kaji, Koichi

2016-01-01

Assessing temporal changes in abundance indices is an important issue in the management of large herbivore populations. The drive counts method has been frequently used as a deer abundance index in mountainous regions. However, despite an inherent risk for observation errors in drive counts, which increase with deer density, evaluations of the utility of drive counts at a high deer density remain scarce. We compared the drive counts and mark-resight (MR) methods in the evaluation of a highly dense sika deer population (MR estimates ranged between 11 and 53 individuals/km2) on Nakanoshima Island, Hokkaido, Japan, between 1999 and 2006. This deer population experienced two large reductions in density; approximately 200 animals in total were taken from the population through a large-scale population removal and a separate winter mass mortality event. Although the drive counts tracked temporal changes in deer abundance on the island, they overestimated the counts for all years in comparison to the MR method. Increased overestimation in drive count estimates after the winter mass mortality event may be due to a double count derived from increased deer movement and recovery of body condition secondary to the mitigation of density-dependent food limitations. Drive counts are unreliable because they are affected by unfavorable factors such as bad weather, and they are cost-prohibitive to repeat, which precludes the calculation of confidence intervals. Therefore, the use of drive counts to infer the deer abundance needs to be reconsidered.

Improving the Acoustical Performance of Porous Asphalt Pavements

DOT National Transportation Integrated Search

1999-09-01

Selection of pavement for noise reduction considerations is becoming a major concern for those involved in highway construction within densely populated areas. However, the pavements available are designed for durability and safety reasons and not fo...

Space Radar Image of Dublin, Ireland

NASA Image and Video Library

1999-04-15

This radar image of Dublin, Ireland, shows how the radar distinguishes between densely populated urban areas and nearby areas that are relatively unsettled. In the center of the image is the city natural harbor along the Irish Sea.

A GIS approach to seismic risk assessment with an application to mining-related seismicity in Johannesburg, South Africa

NASA Astrophysics Data System (ADS)

Liebenberg, Keagen; Smit, Ansie; Coetzee, Serena; Kijko, Andrzej

2017-08-01

The majority of seismic activity in South Africa is related to extensive mining operations, usually in close proximity to densely populated areas where a relatively weak seismic event could cause damage. Despite a significant decrease in mining operations in the Witwatersrand area, the number of seismic events appears to be increasing and is attributed to the acid mine drainage problem. The increased seismicity is raising concern amongst disaster management centres and in the insurance industry. A better understanding is required of the vulnerability and the size of the potential loss of people and infrastructure in densely populated Johannesburg and its surrounding areas. Results of a deterministic seismic risk, vulnerability, and loss assessment are presented by making use of a geographic information system (GIS). The results illustrate the benefits of using GIS and contribute to a better understanding of the risk, which can assist in improving disaster preparedness.

A comparison of families of children with autism spectrum disorders in family daily routines, service usage, and stress levels by regionality.

PubMed

McAuliffe, Tomomi; Vaz, Sharmila; Falkmer, Torbjörn; Cordier, Reinie

2017-11-01

To explore whether family routines, service usage, and stress levels in families of children with autism spectrum disorder differ as a function of regionality. Secondary analysis of data was undertaken from 535 surveys. Univariate and multivariate analyses were performed to investigate differences between families living in densely populated (DP) areas and less densely populated (LDP) areas. Families living in LDP areas were found to: (1) have reduced employment hours (a two-parent household: Exp (B) = 3.48, p < .001, a single-parent household: Exp (B) = 3.32, p = .011); (2) travel greater distance to access medical facilities (Exp (B) = 1.27, p = .006); and (3) report less severe stress levels (Exp (B) = 0.22, p = .014). There were no differences in family routines; however, flexible employment opportunities and travel distance to medical services need to be considered in families living in LDP areas.

Core Emergence in a Massive Infrared Dark Cloud: A Comparison between Mid-IR Extinction and 1.3 mm Emission

NASA Astrophysics Data System (ADS)

Kong, Shuo; Tan, Jonathan C.; Arce, Héctor G.; Caselli, Paola; Fontani, Francesco; Butler, Michael J.

2018-03-01

Stars are born from dense cores in molecular clouds. Observationally, it is crucial to capture the formation of cores in order to understand the necessary conditions and rate of the star formation process. The Atacama Large Millimeter/submillimeter Array (ALMA) is extremely powerful for identifying dense gas structures, including cores, at millimeter wavelengths via their dust continuum emission. Here, we use ALMA to carry out a survey of dense gas and cores in the central region of the massive (∼105 M ⊙) infrared dark cloud (IRDC) G28.37+0.07. The observation consists of a mosaic of 86 pointings of the 12 m array and produces an unprecedented view of the densest structures of this IRDC. In this first Letter about this data set, we focus on a comparison between the 1.3 mm continuum emission and a mid-infrared (MIR) extinction map of the IRDC. This allows estimation of the “dense gas” detection probability function (DPF), i.e., as a function of the local mass surface density, Σ, for various choices of thresholds of millimeter continuum emission to define “dense gas.” We then estimate the dense gas mass fraction, f dg, in the central region of the IRDC and, via extrapolation with the DPF and the known Σ probability distribution function, to the larger-scale surrounding regions, finding values of about 5% to 15% for the fiducial choice of threshold. We argue that this observed dense gas is a good tracer of the protostellar core population and, in this context, estimate a star formation efficiency per free-fall time in the central IRDC region of ɛ ff ∼ 10%, with approximately a factor of two systematic uncertainties.

Evidence for a dwarf galaxy remnant around M82 from deep Hubble Space Telescope imaging

NASA Astrophysics Data System (ADS)

Suwannajak, Chutipong; Sarajedini, Ata

2018-01-01

We present HST/ACS photometry of an over-dense region of stars in the southern halo of the edge-on galaxy M82. The structure is located at a projected distance of 5 kpc from the disk of the galaxy, and its color-magnitude diagram reveals a population of predominantly young stars, which are largely absent from the surrounding halo. Their ages are similar to those of the young stars formed in the tidal debris between M81, M82, and NGC3077 as a result of their interactions. We derive the mean metallicity of the surrounding stars, which are considered to be the halo population of M82, to be similar to that of the red giant branch (RGB) population of the halo of M81. However, the mean metallicity of the RGB in the over-dense structure is significantly more metal-rich than the halo. We theorize that this over-density existed as a dwarf galaxy prior to its interaction with M82 with the young stars forming later from the gas remaining in its main body.

Seasonal dynamics of Aedes aegypti (Diptera: Culicidae) in the northernmost state of Brazil: a likely port-of-entry for dengue virus 4.

PubMed

Codeço, Cláudia Torres; Honório, Nildimar Alves; Ríos-Velásquez, Cláudia M; Santos, Maria da Conceição Alves dos; Mattos, Ingrid Vieira de; Luz, Sérgio Bessa; Reis, Izabel Cristina; Cunha, Guilherme Bernardino da; Rosa-Freitas, Maria Goreti; Tsouris, Pantelis; Castro, Márcia Gonçalves de; Hayd, Ramão Luciano Nogueira; Luitgards-Moura, José Francisco

2009-07-01

Roraima is the northernmost state of Brazil, bordering both Venezuela and Guyana. Appropriate climate and vector conditions for dengue transmission together with its proximity to countries where all four dengue serotypes circulate make this state, particularly the capital Boa Vista, strategically important for dengue surveillance in Brazil. Nonetheless, few studies have addressed the population dynamics of Aedes aegypti in Boa Vista. In this study, we report temporal and spatial variations in Ae. aegypti population density using ovitraps in two highly populated neighbourhoods; Centro and Tancredo Neves. In three out of six surveys, Ae. aegypti was present in more than 80% of the sites visited. High presence levels of this mosquito suggest ubiquitous human exposure to the vector, at least during part of the year. The highest infestation rates occurred during the peak of the rainy seasons, but a large presence was also observed during the early dry season (although with more variation among years). Spatial distribution of positive houses changed from a sparse and local pattern to a very dense pattern during the dry-wet season transition. These results suggest that the risk of dengue transmission and the potential for the new serotype invasions are high for most of the year.

Extinction rate, historical population structure and ecological role of the Caribbean monk seal

PubMed Central

McClenachan, Loren; Cooper, Andrew B

2008-01-01

The productivity and biomass of pristine coral reef ecosystems is poorly understood, particularly in the Caribbean where communities have been impacted by overfishing and multiple other stressors over centuries. Using historical data on the spatial distribution and abundance of the extinct Caribbean monk seal (Monachus tropicalis), this study reconstructs the population size, structure and ecological role of this once common predator within coral reef communities, and provides evidence that historical reefs supported biomasses of fishes and invertebrates up to six times greater than those found on typical modern Caribbean reefs. An estimated 233 000–338 000 monk seals were distributed among 13 colonies across the Caribbean. The biomass of reef fishes and invertebrates required to support historical seal populations was 732–1018 g m−2 of reefs, which exceeds that found on any Caribbean reef today and is comparable with those measured in remote Pacific reefs. Quantitative estimates of historically dense monk seal colonies and their consumption rates on pristine reefs provide concrete data on the magnitude of decline in animal biomass on Caribbean coral reefs. Realistic reconstruction of these past ecosystems is critical to understanding the profound and long-lasting effect of human hunting on the functioning of coral reef ecosystems. PMID:18348965

The type VI secretion system impacts bacterial invasion and population dynamics in a model intestinal microbiota

NASA Astrophysics Data System (ADS)

Logan, Savannah L.; Shields, Drew S.; Hammer, Brian K.; Xavier, Joao B.; Parthasarathy, Raghuveer

Animal gastrointestinal tracts are home to a diverse community of microbes. The mechanisms by which microbial species interact and compete in this dense, physically dynamic space are poorly understood, limiting our understanding of how natural communities are assembled and how different communities could be engineered. Here, we focus on a physical mechanism for competition: the type VI secretion system (T6SS). The T6SS is a syringe-like organelle used by certain bacteria to translocate effector proteins across the cell membranes of target bacterial cells, killing them. Here, we use T6SS+ and T6SS- strains of V. cholerae, the pathogen that causes cholera in humans, and light sheet fluorescence microscopy for in vivo imaging to show that the T6SS provides an advantage to strains colonizing the larval zebrafish gut. Furthermore, we show that T6SS+ bacteria can invade and alter an existing population of a different species in the zebrafish gut, reducing its abundance and changing the form of its population dynamics. This work both demonstrates a mechanism for altering the gut microbiota with an invasive species and explores the processes controlling the stability and dynamics of the gut ecosystem. Research Corporation, Gordon and Betty Moore Foundation, and the Simons Foundation.

Area-based socioeconomic factors and Human Papillomavirus (HPV) vaccination among teen boys in the United States.

PubMed

Henry, Kevin A; Swiecki-Sikora, Allison L; Stroup, Antoinette M; Warner, Echo L; Kepka, Deanna

2017-07-14

This study is the first to examine associations between several area-based socioeconomic factors and human papillomavirus (HPV) vaccine uptake among boys in the United States (U.S.). Data from the 2012-2013 National Immunization Survey-Teen restricted-use data were analyzed to examine associations of HPV vaccination initiation (receipt of ≥1 dose) and series completion (receipt of three doses) among boys aged 13-17 years (N = 19,518) with several individual-level and ZIP Code Tabulation Area (ZCTA) census measures. Multivariable logistic regression was used to estimate the odds of HPV vaccination initiation and series completion separately. In 2012-2013 approximately 27.9% (95% CI 26.6%-29.2%) of boys initiated and 10.38% (95% CI 9.48%-11.29%) completed the HPV vaccine series. Area-based poverty was not statistically significantly associated with HPV vaccination initiation. It was, however, associated with series completion, with boys living in high-poverty areas (≥20% of residents living below poverty) having higher odds of completing the series (AOR 1.22, 95% CI 1.01-1.48) than boys in low-poverty areas (0-4.99%). Interactions between race/ethnicity and ZIP code-level poverty indicated that Hispanic boys living in high-poverty areas had a statistically significantly higher odds of  HPV vaccine initiation (AOR 1.43, 95% CI 1.03-1.97) and series completion (AOR 1.56, 95% CI 1.05-2.32)  than Hispanic boys in  low-poverty areas. Non-Hispanic Black boys in high poverty areas had higher odds of initiation (AOR 2.23, 95% CI 1.33-3.75) and completion (AOR 2.61, 95% CI 1.06-6.44) than non-Hispanic Black boys in low-poverty areas. Rural/urban residence and population density were also significant factors, with boys from urban or densely populated areas having higher odds of initiation and completion compared to boys living in non-urban, less densely populated areas. Higher HPV vaccination coverage in urban areas and among racial/ethnic minorities in areas with high poverty may be attributable to factors such as vaccine acceptance, health-care practices, and their access to HPV vaccines through the Vaccines for Children Program, which provides free vaccines to uninsured and under-insured children. Given the low HPV vaccination rates among boys in the U.S., these results provide important evidence to inform public health interventions to increase HPV vaccination.

Examination of anonymous canine faecal samples provides data on endoparasite prevalence rates in dogs for comparative studies.

PubMed

Hinney, Barbara; Gottwald, Michaela; Moser, Jasmine; Reicher, Bianca; Schäfer, Bhavapriya Jasmin; Schaper, Roland; Joachim, Anja; Künzel, Frank

2017-10-15

Several endoparasites of dogs cannot only be detrimental to their primary host but might also represent a threat to human health because of their zoonotic potential. Due to their high dog population densities, metropolitan areas can be highly endemic for such parasites. We aimed to estimate the prevalence of endoparasites in dogs in the Austrian capital of Vienna by examining a representative number of canine faecal samples and to compare the prevalences with two neighbouring peri-urban and rural regions. In addition we analysed whether the density of dog populations and cleanliness of dog zones correlated with parasite occurrence. We collected 1001 anonymous faecal samples from 55 dog zones from all 23 districts of the federal state of Vienna, as well as 480 faecal samples from the Mödling district and Wolkersdorf with a peri-urban and rural character, respectively. Faeces were examined by flotation and by Baermann technique. Additionally we evaluated 292 Viennese, 102 peri-urban and 50 rural samples for Giardia and Cryptosporidium by GiardiaFASTest ® and CryptoFASTest ® . Samples from "clean" dog zones were compared to samples from "dirty" zones. The infection rate of Toxocara was surprisingly low, ranging from 0.6% to 1.9%. Trichuris was the most frequent helminth (1.8-7.5%) and Giardia the most frequent protozoan (4.0-10.8%). Ancylostomatidae, Crenosoma, Capillaria, Taeniidae, Cystoisospora and Sarcocystis were found in 1.8-2.2%, 0-0.9%, 0-0.9%, 0-0.6%, 0.3-3.1% and 0-0.6% of the samples, respectively. Samples from "dirty" dog zones in Vienna showed a significantly higher rate of parasites overall (p=0.003) and of Trichuris (p=0.048) compared to samples from "clean" dog zones. There were no statistically significant differences in densely vs. less densely populated areas of Vienna. Samples from the rural region of Wolkersdorf had significantly higher overall parasite, Trichuris and Cystoisospora prevalences than the peri-urban Mödling district and Vienna (p=0.000-0.039), while samples from the Mödling district had a significantly higher Giardia, Crenosoma and Capillaria prevalence than those from Vienna (p=0.002-0.047). Parasite excretion is dynamic and representative sampling and monitoring are necessary for parasite surveillance. Dog owners should be informed about the zoonotic risk and encouraged to remove dog faeces and dispose of them properly to reduce the infection risk for both other dogs and humans. Copyright © 2017 Elsevier B.V. All rights reserved.

Societal Influences on Children's Psychology: The Schools in Iceland and Singapore Promote Prosocial Values, Positive Self-Concepts, and Achievement in Young Adolescents

ERIC Educational Resources Information Center

Stiles, Deborah A.

2005-01-01

In most ways the island nations of Iceland and Singapore could not be more different from each other: Iceland is sparsely populated, located near the Arctic Circle, and a very free and individualistic democratic society; Singapore is densely populated, located near the equator, and a very regulated and collectivist meritocracy. But both nations…

Relating Kirtland's warbler population to changing landscape composition and structure

Treesearch

John R. Probst; Jerry Weinrich

1993-01-01

The population of male Kirtland's warbler (Dendroica kirtlandil) in the breeding season has averaged 206 from 1971 to 1987. The Kirtland's warbler occupies dense jack pine (Pinus banksiana) barrens from 5 to 23 years old and from 1.4 to 5.0 m high, formerly of wildfire origin. In 1984, 73% of the males censused were found in habitat naturally regenerated from...

A SNP genetic linkage map based on the ‘Hamilton’ by ‘Spencer’ recombinant inbred line (RIL) population identified QTL for seed Isoflavone contents in soybean

USDA-ARS?s Scientific Manuscript database

Soybean is one of the most important crops worldwide for its protein, oil as well as the health beneficial phytoestrogens or isoflavone. This study reports a relatively dense SNP-Based genetic map based on ‘Hamilton’ by ‘Spencer’ recombinant inbred line (RIL) population and quantitative t...

A Model with Darwinian Dynamics on a Rugged Landscape

NASA Astrophysics Data System (ADS)

Brotto, Tommaso; Bunin, Guy; Kurchan, Jorge

2017-02-01

We discuss the population dynamics with selection and random diffusion, keeping the total population constant, in a fitness landscape associated with Constraint Satisfaction, a paradigm for difficult optimization problems. We obtain a phase diagram in terms of the size of the population and the diffusion rate, with a glass phase inside which the dynamics keeps searching for better configurations, and outside which deleterious `mutations' spoil the performance. The phase diagram is analogous to that of dense active matter in terms of temperature and drive.

[The fear of numbers or the challenge of population growth?].

PubMed

Loriaux, M

1991-12-01

Africa, currently one of the least densely populated continents, is growing so rapidly that its population will comprise some 1.5 billion inhabitants around 2020, and Africans will be more numerous than the population of the developed world. Attitudes about Africa's population size vary widely; many educated Africans believe that low density is a greater disadvantage than overpopulation, but most specialists believe the population of the developing world, and of Africa especially, to be too large, the prospects of significant voluntary reduction are dim. The rate of population growth has thus attracted attention as a factor amenable to modification. Africa's demographic transition remains largely in the future. Its case is unique because of the rate of demographic growth and because the phase of rapid growth will apparently continue far longer in Africa than in any other continent. The widening gap between population growth rates and rates of economic development in Africa inspires great pessimism about the future wellbeing of the population. Population officials urge that demographic growth be slowed in order to reduce pressure on economic and ecological resources and to gain time for social and economic development. But despite the consensus of international organizations, such as the UN Fund for Population, on the desirability of slowing population growth to encourage and permit economic growth, there has actually been relatively little progress since the time of Malthus in understanding the relationship between population, development, and the environment. Some recent works suggest that demographic growth has benefits as well as disadvantages, and the net impact on development is uncertain. Demographic pressure is in this view a far more potent force for innovation than is usually recognized. Population is not just an exogenous variable in development, but it is at the heart of the process. There can be no true integration of population into development until the value of human resources everywhere is reaffirmed. The recognition by international organizations that per capita income or other economic indicators alone are not adequate measures of progress is a favorable sign. The failure of structural adjustment programs to attain their stated goals and the new resolve to lessen their effects on the most vulnerable population sectors are also promising. New orientations toward development in which human resources are given greater prominence may be as ideologically inspired as those they replaced, but they have the merit of greater neutrality concerning the content and form of development and they do not accept the process of development in the West as their sole reference.

Humpback Dolphins in Hong Kong and the Pearl River Delta: Status, Threats and Conservation Challenges.

PubMed

Karczmarski, Leszek; Huang, Shiang-Lin; Or, Carmen K M; Gui, Duan; Chan, Stephen C Y; Lin, Wenzhi; Porter, Lindsay; Wong, Wai-Ho; Zheng, Ruiqiang; Ho, Yuen-Wa; Chui, Scott Y S; Tiongson, Angelico Jose C; Mo, Yaqian; Chang, Wei-Lun; Kwok, John H W; Tang, Ricky W K; Lee, Andy T L; Yiu, Sze-Wing; Keith, Mark; Gailey, Glenn; Wu, Yuping

2016-01-01

In coastal waters of the Pearl River Delta (PRD) region, the Indo-Pacific humpback dolphin (Sousa chinensis) is thought to number approximately 2500 individuals. Given these figures, the putative PRD population may appear strong enough to resist demographic stochasticity and environmental pressures. However, living in close proximity to the world's busiest seaport/airport and several densely populated urban centres with major coastal infrastructural developments comes with challenges to the long-term survival of these animals. There are few other small cetacean populations that face the range and intensity of human-induced pressures as those present in the PRD and current protection measures are severely inadequate. Recent mark-recapture analyses of the animals in Hong Kong waters indicate that in the past two decades the population parameters have not been well understood, and spatial analyses show that only a very small proportion of the dolphins' key habitats are given any form of protection. All current marine protected areas within the PRD fail to meet a minimum habitat requirement that could facilitate the population's long-term persistence. Demographic models indicate a continuous decline of 2.5% per annum, a rate at which the population is likely to drop below the demographic threshold within two generations and lose 74% of the current numbers within the lifespan of three generations. In Hong Kong, the case of humpback dolphins represents a particularly explicit example of inadequate management where a complete revision of the fundamental approach to conservation management is urgently needed. © 2016 Elsevier Ltd All rights reserved.

Uniform, dense arrays of vertically aligned, large-diameter single-walled carbon nanotubes.

PubMed

Han, Zhao Jun; Ostrikov, Kostya

2012-04-04

Precisely controlled reactive chemical vapor synthesis of highly uniform, dense arrays of vertically aligned single-walled carbon nanotubes (SWCNTs) using tailored trilayered Fe/Al(2)O(3)/SiO(2) catalyst is demonstrated. More than 90% population of thick nanotubes (>3 nm in diameter) can be produced by tailoring the thickness and microstructure of the secondary catalyst supporting SiO(2) layer, which is commonly overlooked. The proposed model based on the atomic force microanalysis suggests that this tailoring leads to uniform and dense arrays of relatively large Fe catalyst nanoparticles on which the thick SWCNTs nucleate, while small nanotubes and amorphous carbon are effectively etched away. Our results resolve a persistent issue of selective (while avoiding multiwalled nanotubes and other carbon nanostructures) synthesis of thick vertically aligned SWCNTs whose easily switchable thickness-dependent electronic properties enable advanced applications in nanoelectronic, energy, drug delivery, and membrane technologies.

Planet Earth: Its Past, Our Present, A Future (?)

NASA Astrophysics Data System (ADS)

Kieffer, S. W.

2012-04-01

We who have lived through the second half of the 20th century into the 21st century have witnessed a profound transition in the biological and physical relationship between humans and the rest of the planet. In the middle of the last century, our planet still had undeveloped islands: there were frontiers that held new lands, mysteries, adventures, cultures, and resources. However, these islands have merged into a relatively seamless planet by a mobile and expanding population, science and technology, and global communication. We are subject to stealth as well as natural disasters. Natural disasters result from the ongoing geological and meteorological processes on our planet, increasingly exacerbated by human presence and behavior. Stealth disasters, on the other hand, are caused by humans, but involve the natural systems that support us. Examples of stealth disasters are climate change, loss of soils, acidification of the oceans, desertification, and loss of groundwater resources. Civilization is a complex system. It has emergent properties, and a tuning parameter--a parameter that is "tuned" until the unexpected happens. The tuning parameter for populations is the number of members relative to the capacities that support them. Because of our sheer numbers, we are driving the stealth disasters, and we will be affected more severely by natural disasters than we have been in the past on a less densely populated planet. To guide our thinking about geoethical issues, we propose a (hypothetical) world organization modeled after the Centers for Disease Control (CDC) in the U.S., and call it the Center for Disaster Control for Planet Earth (CDCPE). This center would have a scientific body to provide impartial facts and uncertainties, an engineering body to propose and implement technical solutions, a negotiating body to balance the realities of political, economic, religious and cultural values, and an enforcement body that is responsive to all of the inputs. How shall we start?

Genotypes and Mouse Virulence of Toxoplasma gondii Isolates from Animals and Humans in China

PubMed Central

Liu, Daohua; Huo, Xingxing; Gao, Jiangmei; Song, Xiaorong; Xu, Xiucai; Huang, Kaiquan; Liu, Wenqi; Wang, Yong; Lu, Fangli; Lun, Zhao-Rong; Luo, Qingli; Wang, Xuelong; Shen, Jilong

2013-01-01

Background Recent population structure studies of T. gondii revealed that a few major clonal lineages predominated in different geographical regions. T. gondii in South America is genetically and biologically divergent, whereas this parasite is remarkably clonal in North America and Europe with a few major lineages including Types I, II and III. Information on genotypes and mouse virulence of T. gondii isolates from China is scarce and insufficient to investigate its population structure, evolution, and transmission. Methodology/Principal Findings Genotyping of 23 T. gondii isolates from different hosts using 10 markers for PCR-restriction fragment length polymorphism analyses (SAG1, SAG2, SAG3, BTUB, GRA6, c22-8, c29-2, L358, PK1 and Apico) revealed five genotypes; among them three genotypes were atypical and two were archetypal. Fifteen strains belong to the Chinese 1 lineage, which has been previously reported as a widespread lineage from swine, cats, and humans in China. Two human isolates fall into the type I and II lineages and the remaining isolates belong to two new atypical genotypes (ToxoDB#204 and #205) which has never been reported in China. Our results show that these genotypes of T. gondii isolates are intermediately or highly virulent in mice except for the strain TgCtwh6, which maintained parasitemia in mice for 35 days post infection although it possesses the uniform genotype of Chinese 1. Additionally, phylogenetic network analyses of all isolates of genotype Chinese 1 are identical, and there is no variation based on the sequence data generated for four introns (EF1, HP2, UPRT1 and UPRT7) and two dense granule proteins (GRA6 and GRA7). Conclusion/Significance A limited genetic diversity was found and genotype Chinese 1 (ToxoDB#9) is dominantly circulating in mainland China. The results will provide a useful profile for deep insight to the population structure, epidemiology and biological characteristics of T. gondii in China. PMID:23308233

Dose-dense paclitaxel with carboplatin for advanced ovarian cancer: a feasible treatment alternative.

PubMed

Glaze, Sarah; Teitelbaum, Lisa; Chu, Pamela; Ghatage, Prafull; Nation, Jill; Nelson, Gregg

2013-01-01

Epithelial ovarian cancer is the leading cause of death from gynaecologic cancers in the Western world. If possible, initial cytoreductive surgery is the treatment of choice, followed by adjuvant chemotherapy, usually with a platinum/taxane combination. Increased survival has been recently reported in women who were given adjuvant chemotherapy weekly rather than at three-week intervals, which has been the standard. At our centre, we have been treating patients with advanced ovarian cancer with a dose-dense protocol since March 2010. Treatment is given in an outpatient setting on days 1, 8, and 15 of a 21-day cycle for six cycles. Carboplatin for an AUC of 5 mg/mL/min and paclitaxel 80mg/m² are given on day 1, followed by paclitaxel 80mg/m² on days 8 and 15. Our objective was to determine whether this protocol is a feasible alternative treatment in our population and whether or not the toxicity profile is acceptable. We performed a chart review of 46 patients undergoing treatment with dose-dense chemotherapy for advanced ovarian cancer. Demographic information, patient characteristics, adverse events, and treatment endpoints were recorded. Sixty-one percent of women completed the six-cycle protocol as planned with minimal interruption, which is comparable to the only previously reported trial using this regimen. The most common side effects of treatment were fatigue, neuropathy, and neutropenia. Supplementation with regular magnesium and granulocyte colony-stimulating factor reduced delays. Dose-dense paclitaxel with carboplatin chemotherapy for the treatment of advanced ovarian cancer shows promise in terms of progression-free and overall survival. We have shown this protocol to be practical and feasible in our population.

Cardiovascular and Cerebrovascular Emergency Department Visits Associated With Wildfire Smoke Exposure in California in 2015.

PubMed

Wettstein, Zachary S; Hoshiko, Sumi; Fahimi, Jahan; Harrison, Robert J; Cascio, Wayne E; Rappold, Ana G

2018-04-11

Wildfire smoke is known to exacerbate respiratory conditions; however, evidence for cardiovascular and cerebrovascular events has been inconsistent, despite biological plausibility. A population-based epidemiologic analysis was conducted for daily cardiovascular and cerebrovascular emergency department (ED) visits and wildfire smoke exposure in 2015 among adults in 8 California air basins. A quasi-Poisson regression model was used for zip code-level counts of ED visits, adjusting for heat index, day of week, seasonality, and population. Satellite-imaged smoke plumes were classified as light, medium, or dense based on model-estimated concentrations of fine particulate matter. Relative risk was determined for smoky days for lag days 0 to 4. Rates of ED visits by age- and sex-stratified groups were also examined. Rates of all-cause cardiovascular ED visits were elevated across all lags, with the greatest increase on dense smoke days and among those aged ≥65 years at lag 0 (relative risk 1.15, 95% confidence interval [1.09, 1.22]). All-cause cerebrovascular visits were associated with smoke, especially among those 65 years and older, (1.22 [1.00, 1.49], dense smoke, lag 1). Respiratory conditions were also increased, as anticipated (1.18 [1.08, 1.28], adults >65 years, dense smoke, lag 1). No association was found for the control condition, acute appendicitis. Elevated risks for individual diagnoses included myocardial infarction, ischemic heart disease, heart failure, dysrhythmia, pulmonary embolism, ischemic stroke, and transient ischemic attack. Analysis of an extensive wildfire season found smoke exposure to be associated with cardiovascular and cerebrovascular ED visits for all adults, particularly for those over aged 65 years. © 2018 The Authors. Published on behalf of the American Heart Association, Inc., by Wiley.

Impact of the Growing Population and Energy Demand on the Climatic Conditions of the Indo-Gangetic Basin

NASA Astrophysics Data System (ADS)

Singh, R. P.; Prasad, A. K.; Kafatos, M.

2005-12-01

The Indo-Gangetic (IG) basin is one of the largest basins in the world which is densely populated and suffers with dense fog, haze and smog during winter season. About 500 million people live in the IG basin and due to the dense fog, haze and smog day to day life suffers. India is the third largest producer of the coal in the world and a large share is used in power and industrial sector. The coal used in the power plants is of poor quality (mostly E-F grade or lignite) with high ash content (35-50%) and low calorific value. India's energy consumption has increased 208% from 4.16 quadrillion Btu (quads) in 1980 to 12.8 quads in 2001 with a coal share of ~50.9%. Recent studies using satellite (Moderate Resolution Imaging Spectroradiometer (MODIS) and Multiangle Imaging SpectroRadiometer (MISR)) and AERONET measurements show high aerosol optical depth (AOD) representing the intense air pollution over the IG basin that persists throughout the year. Such high concentrations of AOD show spatial and temporal variations which are controlled by the meteorological conditions (wind pattern, relative humidity, air temperature etc.) and topography. The high AOD observed over the IG basin is attributed to the emissions of fossil fuel SO2 and black carbon which has increased about 6 fold since 1930. The high AOD over the IG basin is attributed to the huge emission from the dense network of coal based thermal power plants in the IG basin and its surroundings that may be the probable cause for the atmospheric brown clouds (ABC). The impact of aerosol parameters on the climatic conditions will be discussed.

Construction of a genome-anchored, high-density genetic map for melon (Cucumis melo L.) and identification of Fusarium oxysporum f. sp. melonis race 1 resistance QTL.

PubMed

Branham, Sandra E; Levi, Amnon; Katawczik, Melanie; Fei, Zhangjun; Wechter, W Patrick

2018-04-01

Four QTLs and an epistatic interaction were associated with disease severity in response to inoculation with Fusarium oxysporum f. sp. melonis race 1 in a recombinant inbred line population of melon. The USDA Cucumis melo inbred line, MR-1, harbors a wealth of alleles associated with resistance to several major diseases of melon, including powdery mildew, downy mildew, Alternaria leaf blight, and Fusarium wilt. MR-1 was crossed to an Israeli cultivar, Ananas Yok'neam, which is susceptible to all of these diseases, to generate a recombinant inbred line (RIL) population of 172 lines. In this study, the RIL population was genotyped to construct an ultra-dense genetic linkage map with 5663 binned SNPs anchored to the C. melo genome and exhibits the overall high quality of the assembly. The utility of the densely genotyped population was demonstrated through QTL mapping of a well-studied trait, resistance to Fusarium wilt caused by Fusarium oxysporum f. sp. melonis (Fom) race 1. A major QTL co-located with the previously validated resistance gene Fom-2. In addition, three minor QTLs and an epistatic interaction contributing to Fom race 1 resistance were identified. The MR-1 × AY RIL population provides a valuable resource for future QTL mapping studies and marker-assisted selection of disease resistance in melon.

Fast Adjustments of the Asian Summer Monsoon to Anthropogenic Aerosols

NASA Astrophysics Data System (ADS)

Li, Xiaoqiong; Ting, Mingfang; Lee, Dong Eun

2018-01-01

Anthropogenic aerosols are a major factor contributing to human-induced climate change, particularly over the densely populated Asian monsoon region. Understanding the physical processes controlling the aerosol-induced changes in monsoon rainfall is essential for reducing the uncertainties in the future projections of the hydrological cycle. Here we use multiple coupled and atmospheric general circulation models to explore the physical mechanisms for the aerosol-driven monsoon changes on different time scales. We show that anthropogenic aerosols induce an overall reduction in monsoon rainfall and circulation, which can be largely explained by the fast adjustments over land north of 20∘N. This fast response occurs before changes in sea surface temperature (SST), largely driven by aerosol-cloud interactions. However, aerosol-induced SST feedbacks (slow response) cause substantial changes in the monsoon meridional circulation over the oceanic regions. Both the land-ocean asymmetry and meridional temperature gradient are key factors in determining the overall monsoon circulation response.

[SARS (Severe Acute Respiratory Syndrome). Emergent transmissible disease].

PubMed

Ivan, A; Azoicăi, Doina

2003-01-01

Of the reemergent transmissible diseases of the past decades, SARS is probably not the last to express the alterations occurring in the relationships of the human being with its global ecosystem. The life of contemporary man is characterized, among others, by a huge thirst for traveling, for varied reasons, consequence of the globalization process. SARS virus, mutant belonging to Coronaviridae, occurred in one of the most densely populated areas of the world. There are two main moments marking the reemergence and evolution of SARS: firstly, the onset of the epidemic in China in November 2002 followed by the worldwide spread of the epidemiological process, and secondly the discovery of SARS virus as a mutant of coronaviruses in March-April 2003 in USA, Canada, and Hong Kong. The possibilities of general and special prevention, and particularly vaccine prevention are likely to bring this disease under control.

The African Genome Variation Project shapes medical genetics in Africa

PubMed Central

Gurdasani, Deepti; Carstensen, Tommy; Tekola-Ayele, Fasil; Pagani, Luca; Tachmazidou, Ioanna; Hatzikotoulas, Konstantinos; Karthikeyan, Savita; Iles, Louise; Pollard, Martin O.; Choudhury, Ananyo; Ritchie, Graham R. S.; Xue, Yali; Asimit, Jennifer; Nsubuga, Rebecca N.; Young, Elizabeth H.; Pomilla, Cristina; Kivinen, Katja; Rockett, Kirk; Kamali, Anatoli; Doumatey, Ayo P.; Asiki, Gershim; Seeley, Janet; Sisay-Joof, Fatoumatta; Jallow, Muminatou; Tollman, Stephen; Mekonnen, Ephrem; Ekong, Rosemary; Oljira, Tamiru; Bradman, Neil; Bojang, Kalifa; Ramsay, Michele; Adeyemo, Adebowale; Bekele, Endashaw; Motala, Ayesha; Norris, Shane A.; Pirie, Fraser; Kaleebu, Pontiano; Kwiatkowski, Dominic; Tyler-Smith, Chris; Rotimi, Charles; Zeggini, Eleftheria; Sandhu, Manjinder S.

2014-01-01

Given the importance of Africa to studies of human origins and disease susceptibility, detailed characterisation of African genetic diversity is needed. The African Genome Variation Project (AGVP) provides a resource to help design, implement and interpret genomic studies in sub-Saharan Africa (SSA) and worldwide. The AGVP represents dense genotypes from 1,481 and whole genome sequences (WGS) from 320 individuals across SSA. Using this resource, we find novel evidence of complex, regionally distinct hunter-gatherer and Eurasian admixture across SSA. We identify new loci under selection, including for malaria and hypertension. We show that modern imputation panels can identify association signals at highly differentiated loci across populations in SSA. Using WGS, we show further improvement in imputation accuracy supporting efforts for large-scale sequencing of diverse African haplotypes. Finally, we present an efficient genotype array design capturing common genetic variation in Africa, showing for the first time that such designs are feasible. PMID:25470054

Ocean outfalls as an alternative to minimizing risks to human and environmental health.

PubMed

Feitosa, Renato Castiglia

2017-06-01

Submarine outfalls are proposed as an efficient alternative for the final destination of wastewater in densely populated coastal areas, due to the high dispersal capacity and the clearance of organic matter in the marine environment, and because they require small areas for implementation. This paper evaluates the probability of unsuitable bathing conditions in coastal areas nearby to the Ipanema, Barra da Tijuca and Icaraí outfalls based on a computational methodology gathering hydrodynamic, pollutant transport, and bacterial decay modelling. The results show a strong influence of solar radiation and all factors that mitigate its levels in the marine environment on coliform concentration. The aforementioned outfalls do not pollute the coastal areas, and unsuitable bathing conditions are restricted to nearby effluent launching points. The pollution observed at the beaches indicates that the contamination occurs due to the polluted estuarine systems, rivers and canals that flow to the coast.

Epidemiology and challenges to the elimination of global tuberculosis.

PubMed

Jassal, Mandeep S; Bishai, William R

2010-05-15

Recent epidemiological indicators of tuberculosis (TB) indicate that the Millennium Development Goal of TB elimination by 2050 will not be achieved. The majority of incident cases are occurring in population-dense regions of Africa and Asia where TB is endemic. The persistence of TB in the setting of poor existing health infrastructure has led to an increase in drug-resistant cases, exacerbated by the strong association with human immunodeficiency virus coinfection. Spreading drug resistance threatens to undo decades of progress in controlling the disease. Several significant gaps can be identified in various aspects of national- and international-directed TB-control efforts. Various governing bodies and international organizations need to address the immediate challenges. This article highlights some of the major policies that lawmakers and funding institutions should consider. Existing economic and social obstacles must be overcome if TB elimination is to be a reachable goal.

Measuring Large-Scale Social Networks with High Resolution

PubMed Central

Stopczynski, Arkadiusz; Sekara, Vedran; Sapiezynski, Piotr; Cuttone, Andrea; Madsen, Mette My; Larsen, Jakob Eg; Lehmann, Sune

2014-01-01

This paper describes the deployment of a large-scale study designed to measure human interactions across a variety of communication channels, with high temporal resolution and spanning multiple years—the Copenhagen Networks Study. Specifically, we collect data on face-to-face interactions, telecommunication, social networks, location, and background information (personality, demographics, health, politics) for a densely connected population of 1 000 individuals, using state-of-the-art smartphones as social sensors. Here we provide an overview of the related work and describe the motivation and research agenda driving the study. Additionally, the paper details the data-types measured, and the technical infrastructure in terms of both backend and phone software, as well as an outline of the deployment procedures. We document the participant privacy procedures and their underlying principles. The paper is concluded with early results from data analysis, illustrating the importance of multi-channel high-resolution approach to data collection. PMID:24770359

Noise level in a pediatric intensive care unit.

PubMed

Carvalho, Werther B; Pedreira, Mavilde L G; de Aguiar, Maria Augusta L

2005-01-01

The purpose of this study was to verify the noise level at a PICU. This prospective observational study was performed in a 10 bed PICU at a teaching hospital located in a densely populated district within the city of São Paulo, Brazil. Sound pressure levels (dBA) were measured 24 hours during a 6-day period. Noise recording equipment was placed in the PICU access corridor, nursing station, two open wards with three and five beds, and in isolation rooms. The resulting curves were analyzed. A basal noise level variation between 60 and 70 dBA was identified, with a maximum level of 120 dBA. The most significant noise levels were recorded during the day and were produced by the staff. The basal noise level identified exceeds International Noise Council recommendations. Education regarding the effects of noise on human hearing and its relation to stress is the essential basis for the development of a noise reduction program.

Can methicillin-resistant Staphylococcus aureus prevalence from dairy cows in India act as potential risk for community-associated infections?: A review

PubMed Central

Gopal, Sathish; Divya, Kurunchi C.

2017-01-01

Methicillin-resistant Staphylococcus aureus (MRSA) is classified as hospital associated (HA), community associated (CA), livestock associated (LA) and is a global concern. Developing countries, like India, are densely populated country challenging for public hygiene practices. HA-MRSA is comfortably recorded in India, and CA-MRSA is also reported as increasing one. CA-MRSA is serious disease which affects the community as endemic. MRSA is one among major mastitis-causing organisms in India as LA-MRSA. There were reports for transmission of MRSA as community between milk handlers and cow in global perspective. In India reports of MRSA in short among milk handlers and also transmission between animal and human. Hence, proper monitoring of MRSA transmission in India should be elucidated in account among milk handlers and dairy cows to avoid emerging CA-MRSA as outbreak. PMID:28435193

Mapping bundles of ecosystem services reveals distinct types of multifunctionality within a Swedish landscape.

PubMed

Queiroz, Cibele; Meacham, Megan; Richter, Kristina; Norström, Albert V; Andersson, Erik; Norberg, Jon; Peterson, Garry

2015-01-01

Ecosystem services (ES) is a valuable concept to be used in the planning and management of social-ecological landscapes. However, the understanding of the determinant factors affecting the interaction between services in the form of synergies or trade-offs is still limited. We assessed the production of 16 ES across 62 municipalities in the Norrström drainage basin in Sweden. We combined GIS data with publically available information for quantifying and mapping the distribution of services. Additionally, we calculated the diversity of ES for each municipality and used correlations and k-means clustering analyses to assess the existence of ES bundles. We found five distinct types of bundles of ES spatially agglomerated in the landscape that could be explained by regional social and ecological gradients. Human-dominated landscapes were highly multifunctional in our study area and urban densely populated areas were hotspots of cultural services.

Diversity, ecology and intestinal function of bifidobacteria

PubMed Central

2014-01-01

The human gastrointestinal tract represents an environment which is a densely populated home for a microbiota that has evolved to positively contribute to host health. At birth the essentially sterile gastrointestinal tract (GIT) is rapidly colonized by microorganisms that originate from the mother and the surrounding environment. Within a short timeframe a microbiota establishes within the (breastfed) infant's GIT where bifidobacteria are among the dominant members, although their numerical dominance disappears following weaning. The numerous health benefits associated with bifidobacteria, and the consequent commercial relevance resulting from their incorporation into functional foods, has led to intensified research aimed at the molecular understanding of claimed probiotic attributes of this genus. In this review we provide the current status on the diversity and ecology of bifidobacteria. In addition, we will discuss the molecular mechanisms that allow this intriguing group of bacteria to colonize and persist in the GIT, so as to facilitate interaction with its host. PMID:25186128

Anthropogenic and natural drivers of gene flow in a temperate wild fruit tree: a basis for conservation and breeding programs in apples

PubMed Central

Cornille, Amandine; Feurtey, Alice; Gélin, Uriel; Ropars, Jeanne; Misvanderbrugge, Kristine; Gladieux, Pierre; Giraud, Tatiana

2015-01-01

Gene flow is an essential component of population adaptation and species evolution. Understanding of the natural and anthropogenic factors affecting gene flow is also critical for the development of appropriate management, breeding, and conservation programs. Here, we explored the natural and anthropogenic factors impacting crop-to-wild and within wild gene flow in apples in Europe using an unprecedented dense sampling of 1889 wild apple (Malus sylvestris) from European forests and 339 apple cultivars (Malus domestica). We made use of genetic, environmental, and ecological data (microsatellite markers, apple production across landscapes and records of apple flower visitors, respectively). We provide the first evidence that both human activities, through apple production, and human disturbance, through modifications of apple flower visitor diversity, have had a significant impact on crop-to-wild interspecific introgression rates. Our analysis also revealed the impact of previous natural climate change on historical gene flow in the nonintrogressed wild apple M. sylvestris, by identifying five distinct genetic groups in Europe and a north–south gradient of genetic diversity. These findings identify human activities and climate as key drivers of gene flow in a wild temperate fruit tree and provide a practical basis for conservation, agroforestry, and breeding programs for apples in Europe. PMID:25926882

Following the footprints of polymorphic inversions on SNP data: from detection to association tests

PubMed Central

Cáceres, Alejandro; González, Juan R.

2015-01-01

Inversion polymorphisms have important phenotypic and evolutionary consequences in humans. Two different methodologies have been used to infer inversions from SNP dense data, enabling the use of large cohorts for their study. One approach relies on the differences in linkage disequilibrium across breakpoints; the other one captures the internal haplotype groups that tag the inversion status of chromosomes. In this article, we assessed the convergence of the two methods in the detection of 20 human inversions that have been reported in the literature. The methods converged in four inversions including inv-8p23, for which we studied its association with low-BMI in American children. Using a novel haplotype tagging method with control on inversion ancestry, we computed the frequency of inv-8p23 in two American cohorts and observed inversion haplotype admixture. Accounting for haplotype ancestry, we found that the European inverted allele in children carries a recessive risk of underweight, validated in an independent Spanish cohort (combined: OR= 2.00, P = 0.001). While the footprints of inversions on SNP data are complex, we show that systematic analyses, such as convergence of different methods and controlling for ancestry, can reveal the contribution of inversions to the ancestral composition of populations and to the heritability of human disease. PMID:25672393

Clinical and epidemiological patterns of Argentine haemorrhagic fever

PubMed Central

Maiztegui, J. I.

1975-01-01

The epidemiology of Argentine haemorrhagic fever (AHF) is closely related to cricetine rodents acting as natural hosts of Junin virus. The endemo-epidemic area, which has increased 5 times since the disease was first recognized 15-20 years ago, is located in a densely populated region of Argentina. It has been shown that the virus of LCM is active in humans and rodents of the AHF endemic area; this demonstrates the simultaneous presence of two arenaviruses pathogenic for man in a given geographic location. The disease is characterized by haematological, renal, neurological and cardiovascular changes. Electron microscopy and immunohistochemical studies have shown cytopathic changes, characteristic intracellular virus-like particles, and antigenic determinants of Junin virus in different organs from 9 cases of AHF. No deposits of immunoglobulins or C3 were found in the kidneys; in addition, an absence of fibrinogen and C3 in the hepatocytes and of immunoglobulins in the spleen was observed. These findings suggest a direct viral pathogenic action in the human disease. Ultrastructural and immunofluorescence studies in tissues of guinea-pigs inoculated with two strains of Junin virus revealed the presence of the same types of virus-like particles and antigenic determinants of Junin virus as were encountered in the human subjects with AHF. ImagesFig. 2Fig. 3 PMID:1085212

Modeling the impacts of wetland restoration in former cranberry farms on nitrogen removal

EPA Science Inventory

In population-dense Massachusetts (USA) acquiring historical wetlands for ecological restoration efforts can be difficult and expensive. Retiring cranberry bogs create a rare opportunity to restore historical wetlands. Environmental managers face important decisions about how to ...

Correlation of In Situ Test Data with Shear Strength for Deep Foundation Design.

DOT National Transportation Integrated Search

2016-06-16

The project addresses drilled shaft foundation design for Nevada, especially for the population center of Las Vegas Valley. Specifically, we address overconservatism due to challenges in characterizing deformability and strength of dense, hard-to-sam...

Cancer incidence in urban, rural, and densely populated districts close to core cities in Bavaria, Germany.

PubMed

Radespiel-Tröger, M; Geiss, K; Twardella, D; Maier, W; Meyer, M

2018-02-01

An ecologic study on the level of districts was performed to evaluate the possible association between district type and risk of cancer in Bavaria, Southern Germany. Cancer incidence data for the years 2003-2012 were obtained from the population-based cancer registry Bavaria according to sex and cancer site. Data on district type, socio-economic area deprivation, particulate matter exposure, tobacco consumption, and alcohol consumption were obtained from publicly available sources. The possible association between district type and cancer risk adjusted for age, socio-economic area deprivation, particulate matter exposure, tobacco consumption, and alcohol consumption was evaluated using multivariable multi-level negative binomial regression. We found a significantly reduced cancer risk in densely populated districts close to core cities and/or rural districts compared to core cities with respect to the cancer sites mouth and pharynx (women only), liver (both sexes), larynx (both sexes), lung (both sexes), melanoma of the skin (both sexes), mesothelioma (men only), connective and soft tissue (both sexes), corpus uteri, other urinary tract (men only), urinary bladder (both sexes), and non-Hodgkin lymphoma (both sexes). Our findings require further monitoring. Since the apparently increased cancer risk in core cities may be related to lifestyle factors, preventive measures against lifestyle-related cancer could be specifically targeted at populations in deprived core cities.

Human Settlements in the South-Central U.S., Viewed at Night from the International Space Station

NASA Technical Reports Server (NTRS)

Dawson, Melissa; Evans, Cynthia; Stefanov, William; Wilkinson, M. Justin; Willis, Kimberly; Runco, Susan

2012-01-01

A recent innovation of astronauts observing Earth from the International Space Station (ISS) is documenting human footprints by photographing city lights at night time. One of the earliest night-time images from the ISS was the US-Mexico border at El Paso-Ciudad Juarez. The colors, patterns and density of city lights document the differences in the cultural settlement patterns across the border region, as well as within the urban areas themselves. City lights help outline the most populated areas in settlements around the world, and can be used to explore relative population densities, changing patterns of urban/suburban development, transportation networks, spatial relationship to geographic features, and more. The data also provides insight into parameters such as surface roughness for input into local and regional climate modeling and studies of light pollution. The ground resolution of night-time astronaut photography from the ISS is typically an order of magnitude greater than current Defense Meteorological Satellite Program (DMSP) data, and therefore can serve as a "zoom lens" for selected urban areas. Current handheld digital cameras in use on the ISS, optimized for greater light sensitivity, provide opportunities to obtain new detailed imagery of atmospheric phenomena such as airglow, aurora, and noctilucent clouds in addition to documenting urban patterns. ISS astronauts have taken advantage of increasingly sensitive digital cameras to document the world at night in unprecedented detail. In addition, the capability to obtain time-lapse imagery from fixed cameras has been exploited to produce dynamic videos of both changing surface patterns around the world and atmospheric phenomena. We will profile some spectacular images of human settlements over the South-Central U.S., and contrast with other images from around the world. More data can be viewed at http://eol.jsc.nasa.gov/Videos/CrewEarthObservationsVideos/. US-Mexico border is obvious by the different lighting pattern. Not surprisingly, the densely illuminated city of Juarez indicates a higher population; El Paso's smaller population is spread out over a larger area.

Polarized Ends of Human Macula Densa Cells: Ultrastructural Investigation and Morphofunctional Correlations.

PubMed

Cangiotti, Angela Maria; Lorenzi, Teresa; Zingaretti, Maria Cristina; Fabri, Mara; Morroni, Manrico

2018-05-01

The morphology of the kidney macula densa (MD) has extensively been investigated in animals, whereas human studies are scanty. We studied the fine structure of human MD cells focusing on their apical and basal ends and correlating structure and function. The MD region was examined by transmission electron microscopy in six renal biopsies from patients with kidney disease. Ultrastructural analysis of MD cells was performed on serial sections. MD cells show two polarized ends. The apical portion is characterized by a single, immotile cilium associated with microvilli; apically, cells are joined by adhering junctions. In the basal portion, the cytoplasm contains small, dense granules and numerous, irregular cytoplasmic projections extending to the adjacent extraglomerular mesangium. The projections often contain small, dense granules. A reticulated basement membrane around MD cells separates them from the extraglomerular mesangium. Although the fact that tissue specimens came from patients with kidney disease mandates extreme caution, ultrastructural examination confirmed that MD cells have sensory features due to the presence of the primary cilium, that they are connected by apical adhering junctions forming a barrier that separates the tubular flow from the interstitium, and that they present numerous basal interdigitations surrounded by a reticulated basement membrane. Conceivably, the latter two features are related to the functional activity of the MD. The small, dense granules in the basal cytoplasm and in cytoplasmic projections are likely related to the paracrine function of MD cells. Anat Rec, 301:922-931, 2018. © 2017 Wiley Periodicals, Inc. © 2017 Wiley Periodicals, Inc.

The Continued Reduction in Dense Fog in the Southern California Region: Possible Causes

NASA Astrophysics Data System (ADS)

LaDochy, S.; Witiw, M.

2012-05-01

Dense fog appears to be decreasing in many parts of the world, especially in western cities. Dense fog (visibility <400 m) is disappearing in the urban southern California area also. There the decrease in dense fog events can be explained mainly by declining particulate levels, Pacific sea surface temperatures (SST), and increased urban warming. Using hourly data from 1948 to the present, we looked at the relationship between fog events in the region and contributing factors and trends over time. Initially a strong relationship was suggested between the occurrence of dense fog and the phases of an atmosphere-ocean cycle: the Pacific Decadal Oscillation (PDO). However, closer analysis revealed the importance to fog variability of an increasing urban heat island and the amount of atmospheric suspended particulate matter. Results show a substantial decrease in the occurrence of very low visibilities (<400 m) at the two airport stations in close proximity to the Pacific Ocean, LAX (Los Angeles International) and LGB (Long Beach International). A downward trend in particulate concentrations, coupled with an upward trend in urban temperatures were associated with the decrease in dense fog occurrence at both LAX and LGB. LAX dense fog that reached over 300 h in 1950 dropped steadily, with 0 h recorded in 1997. Since 1997, there has been a slight recovery with both 2008 and 2009 recording over 30 h of dense fog at both locations. In this study we examine whether the upturn is a temporary reversal of the trend. To remove the urban effect, we also included fog data from Vandenberg Air Force Base (VBG), located in a relatively sparsely populated area approximately 200 km to the north of metropolitan Los Angeles. Particulates, urban heat island, and Pacific SSTs all seem to be contributing factors to the decrease in fog in southern California, along with large-scale atmosphere-ocean interaction cycles. Case studies of local and regional dense fog in southern California point to the importance of strong, low inversions and to a lesser contributor, Santa Ana winds. Both are associated with large-scale atmospheric circulation patterns, which have changed markedly over the period of studied. These changes point to continued decreases in dense fog in the region.

Comparison of Drive Counts and Mark-Resight As Methods of Population Size Estimation of Highly Dense Sika Deer (Cervus nippon) Populations

PubMed Central

Takeshita, Kazutaka; Yoshida, Tsuyoshi; Igota, Hiromasa; Matsuura, Yukiko

2016-01-01

Assessing temporal changes in abundance indices is an important issue in the management of large herbivore populations. The drive counts method has been frequently used as a deer abundance index in mountainous regions. However, despite an inherent risk for observation errors in drive counts, which increase with deer density, evaluations of the utility of drive counts at a high deer density remain scarce. We compared the drive counts and mark-resight (MR) methods in the evaluation of a highly dense sika deer population (MR estimates ranged between 11 and 53 individuals/km2) on Nakanoshima Island, Hokkaido, Japan, between 1999 and 2006. This deer population experienced two large reductions in density; approximately 200 animals in total were taken from the population through a large-scale population removal and a separate winter mass mortality event. Although the drive counts tracked temporal changes in deer abundance on the island, they overestimated the counts for all years in comparison to the MR method. Increased overestimation in drive count estimates after the winter mass mortality event may be due to a double count derived from increased deer movement and recovery of body condition secondary to the mitigation of density-dependent food limitations. Drive counts are unreliable because they are affected by unfavorable factors such as bad weather, and they are cost-prohibitive to repeat, which precludes the calculation of confidence intervals. Therefore, the use of drive counts to infer the deer abundance needs to be reconsidered. PMID:27711181

Identifying positive selection candidate loci for high-altitude adaptation in Andean populations

PubMed Central

2009-01-01

High-altitude environments (>2,500 m) provide scientists with a natural laboratory to study the physiological and genetic effects of low ambient oxygen tension on human populations. One approach to understanding how life at high altitude has affected human metabolism is to survey genome-wide datasets for signatures of natural selection. In this work, we report on a study to identify selection-nominated candidate genes involved in adaptation to hypoxia in one highland group, Andeans from the South American Altiplano. We analysed dense microarray genotype data using four test statistics that detect departures from neutrality. Using a candidate gene, single nucleotide polymorphism-based approach, we identified genes exhibiting preliminary evidence of recent genetic adaptation in this population. These included genes that are part of the hypoxia-inducible transcription factor (HIF) pathway, a biochemical pathway involved in oxygen homeostasis, as well as three other genomic regions previously not known to be associated with high-altitude phenotypes. In addition to identifying selection-nominated candidate genes, we also tested whether the HIF pathway shows evidence of natural selection. Our results indicate that the genes of this biochemical pathway as a group show no evidence of having evolved in response to hypoxia in Andeans. Results from particular HIF-targeted genes, however, suggest that genes in this pathway could play a role in Andean adaptation to high altitude, even if the pathway as a whole does not show higher relative rates of evolution. These data suggest a genetic role in high-altitude adaptation and provide a basis for genotype/phenotype association studies that are necessary to confirm the role of putative natural selection candidate genes and gene regions in adaptation to altitude. PMID:20038496

Pericellular Ca2+ recycling potentiates thrombin-evoked Ca2+ signals in human platelets

PubMed Central

Sage, Stewart O; Pugh, Nicholas; Farndale, Richard W; Harper, Alan G S

2013-01-01

We have previously demonstrated that Na+/Ca2+ exchangers (NCXs) potentiate Ca2+ signaling evoked by thapsigargin in human platelets, via their ability to modulate the secretion of autocoids from dense granules. This link was confirmed in platelets stimulated with the physiological agonist, thrombin, and experiments were performed to examine how Ca2+ removal by the NCX modulates platelet dense granule secretion. In cells loaded with the near-membrane indicator FFP-18, thrombin stimulation was observed to elicit an NCX-dependent accumulation of Ca2+ in a pericellular region around the platelets. To test whether this pericellular Ca2+ accumulation might be responsible for the influence of NCXs over platelet function, platelets were exposed to fast Ca2+ chelators or had their glycocalyx removed. Both manipulations of the pericellular Ca2+ rise reduced thrombin-evoked Ca2+ signals and dense granule secretion. Blocking Ca2+-permeable ion channels had a similar effect, suggesting that Ca2+ exported into the pericellular region is able to recycle back into the platelet cytosol. Single cell imaging with extracellular Fluo-4 indicated that thrombin-evoked rises in extracellular [Ca2+] occurred within the boundary described by the cell surface, suggesting their presence within the open canalicular system (OCS). FFP-18 fluorescence was similarly distributed. These data suggest that upon thrombin stimulation, NCX activity creates a rise in [Ca2+] within the pericellular region of the platelet from where it recycles back into the platelet cytosol, acting to both accelerate dense granule secretion and maintain the initial rise in cytosolic [Ca2+]. PMID:24303163

Synergism between thrombin and adrenaline (epinephrine) in human platelets. Marked potentiation of inositol phospholipid metabolism.

PubMed Central

Steen, V M; Tysnes, O B; Holmsen, H

1988-01-01

We have studied synergism between adrenaline (epinephrine) and low concentrations of thrombin in gel-filtered human platelets prelabelled with [32P]Pi. Suspensions of platelets, which did not contain added fibrinogen, were incubated at 37 degrees C to measure changes in the levels of 32P-labelled phosphatidylinositol 4,5-bisphosphate (PIP2), phosphatidylinositol 4-phosphate (PIP) and phosphatidate (PA), aggregation and dense-granule secretion after stimulation. Adrenaline alone (3.5-4.0 microM) did not cause a change in any parameter (phosphoinositide metabolism, aggregation and dense-granule secretion), but markedly enhanced the thrombin-induced responses over a narrow range of thrombin concentrations (0.03-0.08 units/ml). The thrombin-induced hydrolysis of inositol phospholipids by phospholipase C, which was measured as the formation of [32P]PA, was potentiated by adrenaline, as was the increase in the levels of [32P]PIP2 and [32P]PIP. The presence of adrenaline caused a shift to the left for the thrombin-induced changes in the phosphoinositide metabolism, without affecting the maximal levels of 32P-labelled compounds obtained. A similar shift by adrenaline in the dose-response relationship was previously demonstrated for thrombin-induced aggregation and dense-granule secretion. Also, the narrow range of concentrations of thrombin over which adrenaline potentiates thrombin-induced platelet responses is the same for changes in phosphoinositide metabolism and physiological responses (aggregation and dense-granule secretion). Our observations clearly indicate that adrenaline directly or indirectly influences thrombin-induced changes in phosphoinositide metabolism. PMID:2845924

Simultaneous Inference For The Mean Function Based on Dense Functional Data

PubMed Central

Cao, Guanqun; Yang, Lijian; Todem, David

2012-01-01

A polynomial spline estimator is proposed for the mean function of dense functional data together with a simultaneous confidence band which is asymptotically correct. In addition, the spline estimator and its accompanying confidence band enjoy oracle efficiency in the sense that they are asymptotically the same as if all random trajectories are observed entirely and without errors. The confidence band is also extended to the difference of mean functions of two populations of functional data. Simulation experiments provide strong evidence that corroborates the asymptotic theory while computing is efficient. The confidence band procedure is illustrated by analyzing the near infrared spectroscopy data. PMID:22665964

Identifying Societal Preferences for River Restoration in a Densely Populated Urban Environment: Evidence from a Discrete Choice Experiment in Central Brussels

NASA Astrophysics Data System (ADS)

Chen, Wendy Y.; Liekens, Inge; Broekx, Steven

2017-08-01

One of the major challenges facing river restoration in densely populated urban areas has been the disparity between the expectations of policy-makers and societal preferences. This study aimed to elicit public preferences and elucidate underlying sources of preference heterogeneity, using the Zenne River in central Brussels, Belgium, as a case study. A discrete choice experiment was administered to a representative sample of the Brussels population. Five attributes were specified, including water quality, ecological status, hydromorphological features of channels, recreational opportunities, and monetary cost. Our econometric analysis based on mixed logit models revealed that overall public would like to have a more natural river (open and naturalized channel, good water quality, and with rich species diversity), while achieving good water quality was the most preferred attribute. Respondents categorized as male, non-Belgian citizen, or not being a member of an environmental organization constituted an inclination to prefer the status quo. Belgian citizens showed a pronounced preference for good biodiversity, and being a member of an environmental organization could moderate the strong preference for good water quality. This study provided insights into the relative attractiveness of key attributes pertaining to river restoration, in general, and served as a useful input to the ongoing discussion concerning the future plan for the Zenne River in Brussels, specifically. Possible implications also exist for other urban river restorations in the rest of Europe, where the Water Framework Directive has become a major impetus for the expansion of freshwater ecosystem restoration from rural and peri-urban areas to densely populated urban areas. Particularly, the cultural heterogeneity of societal preferences should be tested and accounted for to compare the welfare impacts of river restoration and to facilitate benefit transfer, within and between river basins, in the Water Framework Directive implementation.

Identifying Societal Preferences for River Restoration in a Densely Populated Urban Environment: Evidence from a Discrete Choice Experiment in Central Brussels.

PubMed

Chen, Wendy Y; Liekens, Inge; Broekx, Steven

2017-08-01

One of the major challenges facing river restoration in densely populated urban areas has been the disparity between the expectations of policy-makers and societal preferences. This study aimed to elicit public preferences and elucidate underlying sources of preference heterogeneity, using the Zenne River in central Brussels, Belgium, as a case study. A discrete choice experiment was administered to a representative sample of the Brussels population. Five attributes were specified, including water quality, ecological status, hydromorphological features of channels, recreational opportunities, and monetary cost. Our econometric analysis based on mixed logit models revealed that overall public would like to have a more natural river (open and naturalized channel, good water quality, and with rich species diversity), while achieving good water quality was the most preferred attribute. Respondents categorized as male, non-Belgian citizen, or not being a member of an environmental organization constituted an inclination to prefer the status quo. Belgian citizens showed a pronounced preference for good biodiversity, and being a member of an environmental organization could moderate the strong preference for good water quality. This study provided insights into the relative attractiveness of key attributes pertaining to river restoration, in general, and served as a useful input to the ongoing discussion concerning the future plan for the Zenne River in Brussels, specifically. Possible implications also exist for other urban river restorations in the rest of Europe, where the Water Framework Directive has become a major impetus for the expansion of freshwater ecosystem restoration from rural and peri-urban areas to densely populated urban areas. Particularly, the cultural heterogeneity of societal preferences should be tested and accounted for to compare the welfare impacts of river restoration and to facilitate benefit transfer, within and between river basins, in the Water Framework Directive implementation.

Future prospects for Nearctic migrants wintering in Carribbean forest

Treesearch

Joseph M. Wunderler JR.; Robert B. Waide

1994-01-01

Wintering nearctic migrants constitute a high proportion of the birds present in many terrestrial habitats in the Bahamas and greater Antilles, But their proportions decline southward through the Lesser Antilles. many migrants winter on densely populate islands which have been extensively deforested.

36 CFR 328.6 - Procedures.

Code of Federal Regulations, 2012 CFR

2012-07-01

... the vicinity of actively used airports, air fields, or densely populated areas. News releases, public... investigation, examination, and determination, consider environmental factors in accordance with the National Environmental Policy Act of 1969 (NEPA), Pub. L. 91-190—particularly should he consider the impact that seaplane...

36 CFR 328.6 - Procedures.

Code of Federal Regulations, 2011 CFR

2011-07-01

... the vicinity of actively used airports, air fields, or densely populated areas. News releases, public... investigation, examination, and determination, consider environmental factors in accordance with the National Environmental Policy Act of 1969 (NEPA), Pub. L. 91-190—particularly should he consider the impact that seaplane...

36 CFR 328.6 - Procedures.

Code of Federal Regulations, 2014 CFR

2014-07-01

... the vicinity of actively used airports, air fields, or densely populated areas. News releases, public... investigation, examination, and determination, consider environmental factors in accordance with the National Environmental Policy Act of 1969 (NEPA), Pub. L. 91-190—particularly should he consider the impact that seaplane...

36 CFR 328.6 - Procedures.

Code of Federal Regulations, 2010 CFR

2010-07-01

... the vicinity of actively used airports, air fields, or densely populated areas. News releases, public... investigation, examination, and determination, consider environmental factors in accordance with the National Environmental Policy Act of 1969 (NEPA), Pub. L. 91-190—particularly should he consider the impact that seaplane...

Estimation of Additive, Dominance, and Imprinting Genetic Variance Using Genomic Data

PubMed Central

Lopes, Marcos S.; Bastiaansen, John W. M.; Janss, Luc; Knol, Egbert F.; Bovenhuis, Henk

2015-01-01

Traditionally, exploration of genetic variance in humans, plants, and livestock species has been limited mostly to the use of additive effects estimated using pedigree data. However, with the development of dense panels of single-nucleotide polymorphisms (SNPs), the exploration of genetic variation of complex traits is moving from quantifying the resemblance between family members to the dissection of genetic variation at individual loci. With SNPs, we were able to quantify the contribution of additive, dominance, and imprinting variance to the total genetic variance by using a SNP regression method. The method was validated in simulated data and applied to three traits (number of teats, backfat, and lifetime daily gain) in three purebred pig populations. In simulated data, the estimates of additive, dominance, and imprinting variance were very close to the simulated values. In real data, dominance effects account for a substantial proportion of the total genetic variance (up to 44%) for these traits in these populations. The contribution of imprinting to the total phenotypic variance of the evaluated traits was relatively small (1–3%). Our results indicate a strong relationship between additive variance explained per chromosome and chromosome length, which has been described previously for other traits in other species. We also show that a similar linear relationship exists for dominance and imprinting variance. These novel results improve our understanding of the genetic architecture of the evaluated traits and shows promise to apply the SNP regression method to other traits and species, including human diseases. PMID:26438289

Gut microbiota of humans, dogs and cats: current knowledge and future opportunities and challenges.

PubMed

Deng, Ping; Swanson, Kelly S

2015-01-01

High-throughput DNA sequencing techniques allow for the identification and characterisation of microbes and their genes (microbiome). Using these new techniques, microbial populations in several niches of the human body, including the oral and nasal cavities, skin, urogenital tract and gastrointestinal tract, have been described recently. Very little data on the microbiome of companion animals exist, and most of the data have been derived from the analysis of the faeces of healthy laboratory animals. High-throughput assays provide opportunities to study the complex and dense populations of the gut microbiota, including bacteria, archaea, fungi, protozoa and viruses. Our laboratory and others have recently described the predominant microbial taxa and genes of healthy dogs and cats and how these respond to dietary interventions. In general, faecal microbial phylogeny (e.g. predominance of Firmicutes, Bacteroidetes, Proteobacteria and Actinobacteria) and functional capacity (e.g. major functional groups related to carbohydrate, protein, DNA and vitamin metabolism; virulence factors; and cell wall and capsule) of the canine and feline gut are similar to those of the human gut. Initial sequencing projects have provided a glimpse of the microbial super-organism that exists within the canine and feline gut, but leaves much to be explored and discovered. As DNA provides information only about potential functions, studies that focus on the microbial transcriptome, metabolite profiles, and how microbiome changes affect host physiology and health are clearly required. Future studies must determine how diet composition, antibiotics and other drug therapies, breed and disease affect or are affected by the gut microbiome and how this information may be used to improve diets, identify disease biomarkers and develop targeted disease therapies.

DETECTING SELECTION IN NATURAL POPULATIONS: MAKING SENSE OF GENOME SCANS AND TOWARDS ALTERNATIVE SOLUTIONS

PubMed Central

Haasl, Ryan J.; Payseur, Bret A.

2016-01-01

Genomewide scans for natural selection (GWSS) have become increasingly common over the last 15 years due to increased availability of genome-scale genetic data. Here, we report a representative survey of GWSS from 1999 to present and find that (i) between 1999 and 2009, 35 of 49 (71%) GWSS focused on human, while from 2010 to present, only 38 of 83 (46%) of GWSS focused on human, indicating increased focus on nonmodel organisms; (ii) the large majority of GWSS incorporate interpopulation or interspecific comparisons using, for example FST, cross-population extended haplotype homozygosity or the ratio of nonsynonymous to synonymous substitutions; (iii) most GWSS focus on detection of directional selection rather than other modes such as balancing selection; and (iv) in human GWSS, there is a clear shift after 2004 from microsatellite markers to dense SNP data. A survey of GWSS meant to identify loci positively selected in response to severe hypoxic conditions support an approach to GWSS in which a list of a priori candidate genes based on potential selective pressures are used to filter the list of significant hits a posteriori. We also discuss four frequently ignored determinants of genomic heterogeneity that complicate GWSS: mutation, recombination, selection and the genetic architecture of adaptive traits. We recommend that GWSS methodology should better incorporate aspects of genomewide heterogeneity using empirical estimates of relevant parameters and/or realistic, whole-chromosome simulations to improve interpretation of GWSS results. Finally, we argue that knowledge of potential selective agents improves interpretation of GWSS results and that new methods focused on correlations between environmental variables and genetic variation can help automate this approach. PMID:26224644

Intensity-dependent resonant transmission of x-rays in solid-density aluminum plasma

NASA Astrophysics Data System (ADS)

Cho, M. S.; Chung, H.-K.; Cho, B. I.

2018-05-01

X-ray free-electron lasers (XFELs) provide unique opportunities to generate and investigate dense plasmas. The absorption and transmission properties of x-ray photons in dense plasmas are important in characterizing the state of the plasmas. Experimental evidence shows that the transmission of x-ray photons through dense plasmas depends greatly on the incident XFEL intensity. Here, we present a detailed analysis of intensity-dependent x-ray transmission in solid-density aluminum using collisional-radiative population kinetics calculations. Reverse saturable absorption (RSA), i.e., an increase in x-ray absorption with intensity has been observed for photon energies below the K-absorption edge and in the intensity range of 1016-1017 W/cm2 for XFEL photons with 1487 eV. At higher intensities, a transition from RSA to saturable absorption (SA) is predicted; thus, the x-ray absorption decreases with intensity above a threshold value. For XFEL photon energies of 1501 eV and 1515 eV, the transition from RSA to SA occurs at XFEL intensities between 1017-1018 W/cm2. Electron temperatures are predicted to be in the range of 30-50 eV for the given experimental conditions. Detailed population kinetics of the charge states explains the intensity-dependent absorption of x-ray photons and the fast modulation of XFEL pulses for both RSA and SA.

Passive Acoustic Monitoring of the Environmental Impact of Oil Exploration on Marine Mammals in the Gulf of Mexico.

PubMed

Sidorovskaia, Natalia A; Ackleh, Azmy S; Tiemann, Christopher O; Ma, Baoling; Ioup, Juliette W; Ioup, George E

2016-01-01

The Gulf of Mexico is a region densely populated by marine mammals that must adapt to living in a highly active industrial environment. This paper presents a new approach to quantifying the anthropogenic impact on the marine mammal population. The results for sperm and beaked whales of a case study of regional population dynamics trends after the Deepwater Horizon oil spill, derived from passive acoustic-monitoring data gathered before and after the spill in the vicinity of the accident, are presented.

Method and apparatus for controlled size distribution of gel microspheres formed from aqueous dispersions. [Patent application

DOEpatents

Ryon, A.D.; Haas, P.A.; Vavruska, J.S.

1982-01-19

The present invention is directed to a method and apparatus for making a population of dense, closely size-controlled microspheres by sol-gel procedures wherein said microspheres are characterized by a significant percentage of said population being within a predetermined, relatively narrow size range. This is accomplished by subjecting aqueous dispersions of a sol, within a water-immiscible organic liquid to a turbulent flow. Microsphere populations thus provided are useful in vibratory-packed processes for nuclear fuels to be irradiated in LWR- and FBR-type nuclear reactors.

Sustaining water resources in South East England

NASA Astrophysics Data System (ADS)

Rodda, John C.

2006-07-01

The South East of England is one of the driest regions of the UK and it is also one of the most densely populated. As a consequence the available water resource per head of population is about half of the figure used by the World Bank to indicate that a country is suffering water stress. The South East Plan, prepared by the South East England Regional Assembly, proposes to increase the population of the region by about 1 million by 2026. This paper considers the ability of the Region's water resources to cope with this growth.

Pricing the urban cooling benefits of solar panel deployment in Sydney, Australia

PubMed Central

Ma, S.; Goldstein, M.; Pitman, A. J.; Haghdadi, N.; MacGill, I.

2017-01-01

Cities import energy, which in combination with their typically high solar absorption and low moisture availability generates the urban heat island effect (UHI). The UHI, combined with human-induced warming, makes our densely populated cities particularly vulnerable to climate change. We examine the utility of solar photovoltaic (PV) system deployment on urban rooftops to reduce the UHI, and we price one potential value of this impact. The installation of PV systems over Sydney, Australia reduces summer maximum temperatures by up to 1 °C because the need to import energy is offset by local generation. This offset has a direct environmental benefit, cooling local maximum temperatures, but also a direct economic value in the energy generated. The indirect benefit associated with the temperature changes is between net AUD$230,000 and $3,380,000 depending on the intensity of PV systems deployment. Therefore, even very large PV installations will not offset global warming, but could generate enough energy to negate the need to import energy, and thereby reduce air temperatures. The energy produced, and the benefits of cooling beyond local PV installation sites, would reduce the vulnerability of urban populations and infrastructure to temperature extremes. PMID:28262843

SuperDCA for genome-wide epistasis analysis.

PubMed

Puranen, Santeri; Pesonen, Maiju; Pensar, Johan; Xu, Ying Ying; Lees, John A; Bentley, Stephen D; Croucher, Nicholas J; Corander, Jukka

2018-05-29

The potential for genome-wide modelling of epistasis has recently surfaced given the possibility of sequencing densely sampled populations and the emerging families of statistical interaction models. Direct coupling analysis (DCA) has previously been shown to yield valuable predictions for single protein structures, and has recently been extended to genome-wide analysis of bacteria, identifying novel interactions in the co-evolution between resistance, virulence and core genome elements. However, earlier computational DCA methods have not been scalable to enable model fitting simultaneously to 10 4 -10 5 polymorphisms, representing the amount of core genomic variation observed in analyses of many bacterial species. Here, we introduce a novel inference method (SuperDCA) that employs a new scoring principle, efficient parallelization, optimization and filtering on phylogenetic information to achieve scalability for up to 10 5 polymorphisms. Using two large population samples of Streptococcus pneumoniae, we demonstrate the ability of SuperDCA to make additional significant biological findings about this major human pathogen. We also show that our method can uncover signals of selection that are not detectable by genome-wide association analysis, even though our analysis does not require phenotypic measurements. SuperDCA, thus, holds considerable potential in building understanding about numerous organisms at a systems biological level.

Spatial epidemiology of suspected clinical leptospirosis in Sri Lanka.

PubMed

Robertson, C; Nelson, T A; Stephen, C

2012-04-01

Leptospirosis is one of the most widespread zoonoses in the world. A large outbreak of suspected human leptospirosis began in Sri Lanka during 2008. This study investigated spatial variables associated with suspected leptospirosis risk during endemic and outbreak periods. Data were obtained for monthly numbers of reported cases of suspected clinical leptospirosis for 2005-2009 for all of Sri Lanka. Space-time scan statistics were combined with regression modelling to test associations during endemic and outbreak periods. The cross-correlation function was used to test association between rainfall and leptospirosis at four locations. During the endemic period (2005-2007), leptospirosis risk was positively associated with shorter average distance to rivers and with higher percentage of agriculture made up of farms <0·20 hectares. Temporal correlation analysis of suspected leptospirosis cases and rainfall revealed a 2-month lag in rainfall-case association during the baseline period. Outbreak locations in 2008 were characterized by shorter distance to rivers and higher population density. The analysis suggests the possibility of household transmission in densely populated semi-urban villages as a defining characteristic of the outbreak. The role of rainfall in the outbreak remains to be investigated, although analysis here suggests a more complex relationship than simple correlation.

Pricing the urban cooling benefits of solar panel deployment in Sydney, Australia.

PubMed

Ma, S; Goldstein, M; Pitman, A J; Haghdadi, N; MacGill, I

2017-03-06

Cities import energy, which in combination with their typically high solar absorption and low moisture availability generates the urban heat island effect (UHI). The UHI, combined with human-induced warming, makes our densely populated cities particularly vulnerable to climate change. We examine the utility of solar photovoltaic (PV) system deployment on urban rooftops to reduce the UHI, and we price one potential value of this impact. The installation of PV systems over Sydney, Australia reduces summer maximum temperatures by up to 1 °C because the need to import energy is offset by local generation. This offset has a direct environmental benefit, cooling local maximum temperatures, but also a direct economic value in the energy generated. The indirect benefit associated with the temperature changes is between net AUD$230,000 and $3,380,000 depending on the intensity of PV systems deployment. Therefore, even very large PV installations will not offset global warming, but could generate enough energy to negate the need to import energy, and thereby reduce air temperatures. The energy produced, and the benefits of cooling beyond local PV installation sites, would reduce the vulnerability of urban populations and infrastructure to temperature extremes.

Demonstration of long-term increases in tropospheric O3 levels: causes and potential impacts.

PubMed

Susaya, Janice; Kim, Ki-Hyun; Shon, Zang-Ho; Brown, Richard J C

2013-09-01

Ground-level ozone (O3) is a well-known atmospheric pollutant with its adverse impacts on the environment and human health. Here, the tropospheric O3 concentrations monitored in seven major cities in Korea at monthly intervals over a 22-year period (1989-2010) are presented, and their long-term variability examined. The analysis of annual mean values of O3 (in nmolmol(-1), or ppb) showed a noticeable increase of 118±69% in all seven cities over the two decades (p<0.01). Changes in O3 levels are closely associated with both environmental (e.g., NOx (NO+NO2), SO2, CO, and total suspended particles (TSPs) (p<0.01), temperature, and sunshine hours) and common anthropogenic variables (e.g., population density and number of vehicles). Evidence collected in this study suggests that the atmospheric conditions in most major cities of Korea should be volatile organic compounds (VOCs) sensitive or NOx saturated with respect to O3 formation. As such, establishment of a proper management strategy seems a sensible approach to control tropospheric ozone concentrations in densely populated cities. Copyright © 2013 Elsevier Ltd. All rights reserved.

Accumulation of microplastic on shorelines woldwide: sources and sinks.

PubMed

Browne, Mark Anthony; Crump, Phillip; Niven, Stewart J; Teuten, Emma; Tonkin, Andrew; Galloway, Tamara; Thompson, Richard

2011-11-01

Plastic debris <1 mm (defined here as microplastic) is accumulating in marine habitats. Ingestion of microplastic provides a potential pathway for the transfer of pollutants, monomers, and plastic-additives to organisms with uncertain consequences for their health. Here, we show that microplastic contaminates the shorelines at 18 sites worldwide representing six continents from the poles to the equator, with more material in densely populated areas, but no clear relationship between the abundance of miocroplastics and the mean size-distribution of natural particulates. An important source of microplastic appears to be through sewage contaminated by fibers from washing clothes. Forensic evaluation of microplastic from sediments showed that the proportions of polyester and acrylic fibers used in clothing resembled those found in habitats that receive sewage-discharges and sewage-effluent itself. Experiments sampling wastewater from domestic washing machines demonstrated that a single garment can produce >1900 fibers per wash. This suggests that a large proportion of microplastic fibers found in the marine environment may be derived from sewage as a consequence of washing of clothes. As the human population grows and people use more synthetic textiles, contamination of habitats and animals by microplastic is likely to increase.

Railway Embankments as New Habitat for Pollinators in an Agricultural Landscape

PubMed Central

Moroń, Dawid; Skórka, Piotr; Lenda, Magdalena; Rożej-Pabijan, Elżbieta; Wantuch, Marta; Kajzer-Bonk, Joanna; Celary, Waldemar; Mielczarek, Łukasz Emil; Tryjanowski, Piotr

2014-01-01

Pollinating insect populations, essential for maintaining wild plant diversity and agricultural productivity, rely on (semi)natural habitats. An increasing human population is encroaching upon and deteriorating pollinator habitats. Thus the population persistence of pollinating insects and their associated ecosystem services may depend upon on man-made novel habitats; however, their importance for ecosystem services is barely understood. We tested if man-made infrastructure (railway embankments) in an agricultural landscape establishes novel habitats that support large populations of pollinators (bees, butterflies, hoverflies) when compared to typical habitats for these insects, i.e., semi-natural grasslands. We also identified key environmental factors affecting the species richness and abundance of pollinators on embankments. Species richness and abundance of bees and butterflies were higher for railway embankments than for grasslands. The occurrence of bare (non-vegetated) ground on embankments positively affected bee species richness and abundance, but negatively affected butterfly populations. Species richness and abundance of butterflies positively depended on species richness of native plants on embankments, whereas bee species richness was positively affected by species richness of non-native flowering plants. The density of shrubs on embankments negatively affected the number of bee species and their abundance. Bee and hoverfly species richness were positively related to wood cover in a landscape surrounding embankments. This is the first study showing that railway embankments constitute valuable habitat for the conservation of pollinators in farmland. Specific conservation strategies involving embankments should focus on preventing habitat deterioration due to encroachment of dense shrubs and maintaining grassland vegetation with patches of bare ground. PMID:25054427

Progressive Seismic Failure, Seismic Gap, and Great Seismic Risk across the Densely Populated North China Basin

NASA Astrophysics Data System (ADS)

Yin, A.; Yu, X.; Shen, Z.

2014-12-01

Although the seismically active North China basin has the most complete written records of pre-instrumentation earthquakes in the world, this information has not been fully utilized for assessing potential earthquake hazards of this densely populated region that hosts ~200 million people. In this study, we use the historical records to document the earthquake migration pattern and the existence of a 180-km seismic gap along the 600-km long right-slip Tangshan-Hejian-Cixian (THC) fault zone that cuts across the North China basin. The newly recognized seismic gap, which is centered at Tianjin with a population of 11 million people and ~120 km from Beijing (22 million people) and Tangshan (7 million people), has not been ruptured in the past 1000 years by M≥6 earthquakes. The seismic migration pattern in the past millennium suggests that the epicenters of major earthquakes have shifted towards this seismic gap along the THC fault, which implies that the 180- km gap could be the site of the next great earthquake with M≈7.6 if it is ruptured by a single event. Alternatively, the seismic gap may be explained by aseismic creeping or seismic strain transfer between active faults.

Expression of Human Complement Factor H Prevents Age-Related Macular Degeneration–Like Retina Damage and Kidney Abnormalities in Aged Cfh Knockout Mice

PubMed Central

Ding, Jin-Dong; Kelly, Una; Landowski, Michael; Toomey, Christopher B.; Groelle, Marybeth; Miller, Chelsey; Smith, Stephanie G.; Klingeborn, Mikael; Singhapricha, Terry; Jiang, Haixiang; Frank, Michael M.; Bowes Rickman, Catherine

2016-01-01

Complement factor H (CFH) is an important regulatory protein in the alternative pathway of the complement system, and CFH polymorphisms increase the genetic risk of age-related macular degeneration dramatically. These same human CFH variants have also been associated with dense deposit disease. To mechanistically study the function of CFH in the pathogenesis of these diseases, we created transgenic mouse lines using human CFH bacterial artificial chromosomes expressing full-length human CFH variants and crossed these to Cfh knockout (Cfh−/−) mice. Human CFH protein inhibited cleavage of mouse complement component 3 and factor B in plasma and in retinal pigment epithelium/choroid/sclera, establishing that human CFH regulates activation of the mouse alternative pathway. One of the mouse lines, which express relatively higher levels of CFH, demonstrated functional and structural protection of the retina owing to the Cfh deletion. Impaired visual function, detected as a deficit in the scotopic electroretinographic response, was improved in this transgenic mouse line compared with Cfh−/− mice, and transgenics had a thicker outer nuclear layer and less sub–retinal pigment epithelium deposit accumulation. In addition, expression of human CFH also completely protected the mice from developing kidney abnormalities associated with loss of CFH. These humanized CFH mice present a valuable model for study of the molecular mechanisms of age-related macular degeneration and dense deposit disease and for testing therapeutic targets. PMID:25447048

Building a Hypertextual Digital Library in the Humanities: A Case Study on London.

ERIC Educational Resources Information Center

Crane, Gregory; Smith, David A.; Wulfman, Clifford E.

This paper describes the creation of a new humanities digital library collection: 11,000,000 words and 10,000 images representing books, images, and maps on pre-twentieth century London and its environs. The London collection contained far more dense and precise information than the materials from the Greco-Roman world. The London collection thus…

The Convention on the Rights of Persons with Disabilities: Notes on Genealogy and Prospects

ERIC Educational Resources Information Center

Winzer, Margret; Mazurek, Kas

2014-01-01

The dense and complex "Convention on the Rights of Persons with Disabilities" (CRPD) is both a human rights treaty and a development tool. It supplements the web of existing human rights instruments insofar as they relate to disability. Schooling is enshrouded as a rights-based case; inclusive education as a development tool for all…

The universal existence of myodural bridge in mammals: an indication of a necessary function.

PubMed

Zheng, Nan; Yuan, Xiao-Ying; Chi, Yan-Yan; Liu, Pei; Wang, Bing; Sui, Jia-Ying; Han, Seung-Ho; Yu, Sheng-Bo; Sui, Hong-Jin

2017-08-15

The "myodural bridge" was described in literatures as a dense fibrous tissue connecting the sub-occipital musculature with the spinal dura mater in human studies. Now the concept of "myodural bridge" was perceived as an exact anatomical structure presumably essential for critical physiological functions in human body, and might exist in other mammals as well. To determine the existence of the "myodural bridge" in other mammals and to lay a foundation for the functional study, we examined representatives in five different mammalian orders. Based on the anatomical dissections, P45 plastinated sections and histological sections, we found that a dense fibrous tissue connected the rectus capitisdorsalis minor and the spinal dura mater through the dorsal atlanto-occipital interspace with or without the medium of the posterior atlanto-occipital membrane. These observed connective tissues were very similar to the "myodural bridge" previously described in humans. We proposed that the "myodural bridge", as an evolutionally conserved structure, presents in many other mammals. Moreover, we believed that the "myodural bridge" might be a homologous organ in mammals. Thus, this study could provide an insight for our understanding the physiological significance of the "myodural bridge", especially in human.

Altered behavior in spotted hyenas associated with increased human activity

USGS Publications Warehouse

Boydston, Erin E.; Kapheim, Karen M.; Watts, Heather E.; Szykman, Micaela; Holekamp, Kay E.

2003-01-01

To investigate how anthropogenic activity might affect large carnivores, we studied the behaviour of spotted hyenas (Crocuta crocuta) during two time periods. From 1996 to 1998, we documented the ecological correlates of space utilization patterns exhibited by adult female hyenas defending a territory at the edge of a wildlife reserve in Kenya. Hyenas preferred areas near dense vegetation but appeared to avoid areas containing the greatest abundance of prey, perhaps because these were also the areas of most intensive livestock grazing. We then compared hyena behaviour observed in 1996–98 with that observed several years earlier and found many differences. Female hyenas in 1996–98 were found farther from dens, but closer to dense vegetation and to the edges of their territory, than in 1988–90. Recent females also had larger home ranges, travelled farther between consecutive sightings, and were more nocturnal than in 1988–90. Finally, hyenas occurred in smaller groups in 1996–98 than in 1988–90. We also found several changes in hyena demography between periods. We next attempted to explain differences observed between time periods by testing predictions of hypotheses invoking prey abundance, climate, interactions with lions, tourism and livestock grazing. Our data were consistent with the hypothesis that increased reliance on the reserve for livestock grazing was responsible for observed changes. That behavioural changes were not associated with decreased hyena population density suggests the behavioural plasticity typical of this species may protect it from extinction.

Bioprinting Perfusion-Enabled Liver Equivalents for Advanced Organ-on-a-Chip Applications.

PubMed

Grix, Tobias; Ruppelt, Alicia; Thomas, Alexander; Amler, Anna-Klara; Noichl, Benjamin P; Lauster, Roland; Kloke, Lutz

2018-03-22

Many tissue models have been developed to mimic liver-specific functions for metabolic and toxin conversion in in vitro assays. Most models represent a 2D environment rather than a complex 3D structure similar to native tissue. To overcome this issue, spheroid cultures have become the gold standard in tissue engineering. Unfortunately, spheroids are limited in size due to diffusion barriers in their dense structures, limiting nutrient and oxygen supply. Recent developments in bioprinting techniques have enabled us to engineer complex 3D structures with perfusion-enabled channel systems to ensure nutritional supply within larger, densely-populated tissue models. In this study, we present a proof-of-concept for the feasibility of bioprinting a liver organoid by combining HepaRG and human stellate cells in a stereolithographic printing approach, and show basic characterization under static cultivation conditions. Using standard tissue engineering analytics, such as immunohistology and qPCR, we found higher albumin and cytochrome P 450 3A4 (CYP3A4) expression in bioprinted liver tissues compared to monolayer controls over a two-week cultivation period. In addition, the expression of tight junctions, liver-specific bile transporter multidrug resistance-associated protein 2 (MRP2), and overall metabolism (glucose, lactate, lactate dehydrogenase (LDH)) were found to be stable. Furthermore, we provide evidence for the perfusability of the organoids' intrinsic channel system. These results motivate new approaches and further development in liver tissue engineering for advanced organ-on-a-chip applications and pharmaceutical developments.

Mapping the Ancient Maya Landscape from Space

NASA Technical Reports Server (NTRS)

Sever, Tom

2003-01-01

This project uses new satellite and airborne imagery in combination with remote sensing, GIS, and GPS technology to understand the dynamics of how the Maya successfully interacted with their karst topographic landscape for several centuries in the northern Peten region of Guatemala. The ancient Maya attained one of the greatest population densities in human history in the tropical forest of the Peten, Guatemala, and it was in this region that the Maya civilization began, flourished, and abruptly disappeared for unknown reasons around AD 800. How the Maya were able to successfully manage water and feed this dense population is not known at this time. However, a recent NASA-funded project was the first to investigate large seasonal swamps (bajos) that make up 40 percent of the landscape. Through the use of remote sensing, ancient Maya features such as cities, roadways, canals and water reservoirs have been detected and verified through ground reconnaissance. The results of this research cast new light on the adaptation of the ancient Maya to their environment. Micro-environmental variation within the wetlands was elucidated and the different vegetational associations identified in the satellite imagery. More than 70 new archeological sites within and at the edges of the bajo were mapped and tested. Modification of the landscape by the Maya in the form of dams and reservoirs in the Holmul River and its tributaries and possible drainage canals in bajos was demonstrated. The recent acquisition of one-meter IKONOS imagery and high resolution STAR-3i radar imagery (2.5m backscatter/ 10m DEM), opens new possibilities for understanding how a civilization was able to survive for centuries upon a karst topographic landscape and their human-induced effects upon the local climate. This understanding is critical for the current population that is presently experiencing rapid population growth and destroying the landscape through non-traditional farming and grazing techniques, resulting in socioeconomic problems.

Ecological host fitting of Trypanosoma cruzi TcI in Bolivia: mosaic population structure, hybridization and a role for humans in Andean parasite dispersal.

PubMed

Messenger, Louisa A; Garcia, Lineth; Vanhove, Mathieu; Huaranca, Carlos; Bustamante, Marinely; Torrico, Marycruz; Torrico, Faustino; Miles, Michael A; Llewellyn, Martin S

2015-05-01

An improved understanding of how a parasite species exploits its genetic repertoire to colonize novel hosts and environmental niches is crucial to establish the epidemiological risk associated with emergent pathogenic genotypes. Trypanosoma cruzi, a genetically heterogeneous, multi-host zoonosis, provides an ideal system to examine the sylvatic diversification of parasitic protozoa. In Bolivia, T. cruzi I, the oldest and most widespread genetic lineage, is pervasive across a range of ecological clines. High-resolution nuclear (26 loci) and mitochondrial (10 loci) genotyping of 199 contemporaneous sylvatic TcI clones was undertaken to provide insights into the biogeographical basis of T. cruzi evolution. Three distinct sylvatic parasite transmission cycles were identified: one highland population among terrestrial rodent and triatomine species, composed of genetically homogenous strains (Ar = 2.95; PA/L = 0.61; DAS = 0.151), and two highly diverse, parasite assemblages circulating among predominantly arboreal mammals and vectors in the lowlands (Ar = 3.40 and 3.93; PA/L = 1.12 and 0.60; DAS = 0.425 and 0.311, respectively). Very limited gene flow between neighbouring terrestrial highland and arboreal lowland areas (distance ~220 km; FST = 0.42 and 0.35) but strong connectivity between ecologically similar but geographically disparate terrestrial highland ecotopes (distance >465 km; FST = 0.016-0.084) strongly supports ecological host fitting as the predominant mechanism of parasite diversification. Dissimilar heterozygosity estimates (excess in highlands, deficit in lowlands) and mitochondrial introgression among lowland strains may indicate fundamental differences in mating strategies between populations. Finally, accelerated parasite dissemination between densely populated, highland areas, compared to uninhabited lowland foci, likely reflects passive, long-range anthroponotic dispersal. The impact of humans on the risk of epizootic Chagas disease transmission in Bolivia is discussed. © 2015 John Wiley & Sons Ltd.

Assessing the presence of Wuchereria bancrofti in vector and human populations from urban communities in Conakry, Guinea.

PubMed

Kouassi, Bernard L; de Souza, Dziedzom K; Goepogui, Andre; Narh, Charles A; King, Sandra A; Mamadou, Baldé S; Diakité, Lamia; Dadzie, Samuel K; Boakye, Daniel A; Utzinger, Jürg; Bockarie, Moses J; Koudou, Benjamin G

2015-09-26

The Global Programme to Eliminate Lymphatic Filariasis was launched in 2000 with the goal of interrupting transmission of lymphatic filariasis (LF) through multiple rounds of mass drug administration (MDA). In Guinea, there is evidence of ongoing LF transmission, but little is known about the most densely populated parts of the country, including the capital Conakry. In order to guide the LF control and elimination efforts, serological and entomological surveys were carried out to determine whether or not LF transmission occurs in Conakry. The prevalence of circulating filarial antigen (CFA) of Wuchereria bancrofti was assessed by an immuno-chromatography test (ICT) in people recruited from all five districts of Conakry. Mosquitoes were collected over a 1-year period, in 195 households in 15 communities. A proportion of mosquitoes were analysed for W. bancrofti, using dissection, loop-mediated isothermal amplification (LAMP) assay and conventional polymerase chain reaction (PCR). CFA test revealed no infection in the 611 individuals examined. A total of 14,334 mosquitoes were collected; 14,135 Culex (98.6 %), 161 Anopheles (1.1 %) and a few other species. Out of 1,312 Culex spp. (9.3 %) and 51 An. gambiae (31.7 %) dissected, none was infected with any stage of the W. bancrofti parasite. However, the LAMP assay revealed that 1.8 % of An. gambiae and 0.31 % of Culex spp. were positive, while PCR determined respective prevalences of 0 % and 0.19 %. This study revealed the presence of W. bancrofti DNA in mosquitoes, despite the apparent absence of infection in the human population. Although MDA interventions are not recommended where the prevalence of ICT is below 1 %, the entomological results are suggestive of the circulation of the parasite in the population of Conakry. Therefore, rigorous surveillance is still warranted so that LF transmission in Conakry would be identified rapidly and adequate responses being implemented.

Inference and Analysis of Population Structure Using Genetic Data and Network Theory

PubMed Central

Greenbaum, Gili; Templeton, Alan R.; Bar-David, Shirli

2016-01-01

Clustering individuals to subpopulations based on genetic data has become commonplace in many genetic studies. Inference about population structure is most often done by applying model-based approaches, aided by visualization using distance-based approaches such as multidimensional scaling. While existing distance-based approaches suffer from a lack of statistical rigor, model-based approaches entail assumptions of prior conditions such as that the subpopulations are at Hardy-Weinberg equilibria. Here we present a distance-based approach for inference about population structure using genetic data by defining population structure using network theory terminology and methods. A network is constructed from a pairwise genetic-similarity matrix of all sampled individuals. The community partition, a partition of a network to dense subgraphs, is equated with population structure, a partition of the population to genetically related groups. Community-detection algorithms are used to partition the network into communities, interpreted as a partition of the population to subpopulations. The statistical significance of the structure can be estimated by using permutation tests to evaluate the significance of the partition’s modularity, a network theory measure indicating the quality of community partitions. To further characterize population structure, a new measure of the strength of association (SA) for an individual to its assigned community is presented. The strength of association distribution (SAD) of the communities is analyzed to provide additional population structure characteristics, such as the relative amount of gene flow experienced by the different subpopulations and identification of hybrid individuals. Human genetic data and simulations are used to demonstrate the applicability of the analyses. The approach presented here provides a novel, computationally efficient model-free method for inference about population structure that does not entail assumption of prior conditions. The method is implemented in the software NetStruct (available at https://giligreenbaum.wordpress.com/software/). PMID:26888080

Inference and Analysis of Population Structure Using Genetic Data and Network Theory.

PubMed

Greenbaum, Gili; Templeton, Alan R; Bar-David, Shirli

2016-04-01

Clustering individuals to subpopulations based on genetic data has become commonplace in many genetic studies. Inference about population structure is most often done by applying model-based approaches, aided by visualization using distance-based approaches such as multidimensional scaling. While existing distance-based approaches suffer from a lack of statistical rigor, model-based approaches entail assumptions of prior conditions such as that the subpopulations are at Hardy-Weinberg equilibria. Here we present a distance-based approach for inference about population structure using genetic data by defining population structure using network theory terminology and methods. A network is constructed from a pairwise genetic-similarity matrix of all sampled individuals. The community partition, a partition of a network to dense subgraphs, is equated with population structure, a partition of the population to genetically related groups. Community-detection algorithms are used to partition the network into communities, interpreted as a partition of the population to subpopulations. The statistical significance of the structure can be estimated by using permutation tests to evaluate the significance of the partition's modularity, a network theory measure indicating the quality of community partitions. To further characterize population structure, a new measure of the strength of association (SA) for an individual to its assigned community is presented. The strength of association distribution (SAD) of the communities is analyzed to provide additional population structure characteristics, such as the relative amount of gene flow experienced by the different subpopulations and identification of hybrid individuals. Human genetic data and simulations are used to demonstrate the applicability of the analyses. The approach presented here provides a novel, computationally efficient model-free method for inference about population structure that does not entail assumption of prior conditions. The method is implemented in the software NetStruct (available at https://giligreenbaum.wordpress.com/software/). Copyright © 2016 by the Genetics Society of America.

Potential Population Consequences of Active Sonar Disturbance in Atlantic Herring: Estimating the Maximum Risk.

PubMed

Sivle, Lise Doksæter; Kvadsheim, Petter Helgevold; Ainslie, Michael

2016-01-01

Effects of noise on fish populations may be predicted by the population consequence of acoustic disturbance (PCAD) model. We have predicted the potential risk of population disturbance when the highest sound exposure level (SEL) at which adult herring do not respond to naval sonar (SEL(0)) is exceeded. When the population density is low (feeding), the risk is low even at high sonar source levels and long-duration exercises (>24 h). With densely packed populations (overwintering), a sonar exercise might expose the entire population to levels >SEL(0) within a 24-h exercise period. However, the disturbance will be short and the response threshold used here is highly conservative. It is therefore unlikely that naval sonar will significantly impact the herring population.

Recruiting Implications of the Long War for the Marine Corps

DTIC Science & Technology

2008-01-01

forecast future demographic complexion. Thus today’s marketing and advertising efforts can be tailored to shape tomorrow’s desired force diversity... marketing and advertising campaign. Continue to place Hispanic recruiters in urban centers with dense Hispanic population. Lastly, the Marine Corps

STS-36 night Earth observation of New York City, New York

NASA Image and Video Library

1990-03-03

STS-36 Earth observation shows New York City, New York at night lit up along the Eastern seaboard of the United States and the Atlantic Ocean. The city lights designate the densely populated central city and the major highways surrounding it.

36 CFR § 328.6 - Procedures.

Code of Federal Regulations, 2013 CFR

2013-07-01

... the vicinity of actively used airports, air fields, or densely populated areas. News releases, public... investigation, examination, and determination, consider environmental factors in accordance with the National Environmental Policy Act of 1969 (NEPA), Pub. L. 91-190—particularly should he consider the impact that seaplane...

Assessing importance and satisfaction with factors in intermodal work commuting : [research brief].

DOT National Transportation Integrated Search

2012-02-01

A frequently referenced public policy goal is to reduce or limit the growth of single-passenger private vehicle use for routine trips. This policy goal continues to have limited success in the densely populated travel corridors of California. The wor...

The disease complex of the gypsy moth. II. Aerobic bacterial pathogens

Treesearch

J.D. Podgwaite; R.W. Campbell

1972-01-01

Eighty-six pathogenic aerobic bacterial isolates from diseased gypsy moth larvae collected in both sparse and dense populations were characterized and identified as members of the families Bacillaceae, Enterobacteriaceae, Lactobacillaceae, Pseudomonadaceae, and Achromobacteraceae. The commonest pathogens were Streptococcus faecalis, Bacillus cereus, Bacillus...

High-resolution maps of forest-urban watersheds present an opportunity for ecologists and managers

EPA Science Inventory

Dense populations of people and abundant impervious surfaces contribute to poor water quality and increased flooding in forest-urban watersheds. Green infrastructure mitigates these effects, but precisely quantifying benefits is difficult because most land cover maps rely on coar...

Urban Heat Island Over Delhi Punches Holes in Widespread Fog in the Indo-Gangetic Plains

NASA Astrophysics Data System (ADS)

Gautam, Ritesh; Singh, Manoj K.

2018-01-01

Persistent and widespread fog affects several densely populated and agriculturally fertile basins around the world. Dense and polluted fog is especially known to impact transportation, air quality, and public health. Here we report a striking observation of holes in fog over urban areas in satellite imagery. The extent of fog holes appear highly correlated with city populations in fog-prevalent regions of Asia, Europe, and the United States. We find the highest frequency and largest extent of fog holes over Delhi along with suppressed fog fraction, amidst increased fog occurrence over the Indo-Gangetic Plains, based on 17 years of satellite data (2000-2016). This apparent urban heat impact is characterized in sharp urban-rural gradients in surface temperatures and fog thickness. Urban heating seems to have already amplified the long-term fog decline in Europe and the United States and should be assessed over regions undergoing urban expansion including India, where no previous linkages are reported between urban heating and fog.

Traditional food consumption is associated with better diet quality and adequacy among Inuit adults in Nunavut, Canada.

PubMed

Sheehy, Tony; Kolahdooz, Fariba; Roache, Cindy; Sharma, Sangita

2015-01-01

The Inuit population is undergoing a rapid nutrition transition as a result of reduced consumption of traditional foods. This study aims to describe the differences in dietary adequacy between non-traditional and traditional eaters among Inuit populations in Nunavut, Canada. A cross-sectional survey was conducted using a culturally appropriate quantitative food frequency questionnaire. Participants included 208 Inuit adults from three isolated communities in Nunavut. Traditional eaters consumed a more nutrient-dense diet and achieved better dietary adequacy than non-traditional eaters. Traditional foods accounted for 7 and 27% of energy intake among non-traditional and traditional eaters, respectively. Non-nutrient-dense foods accounted for a greater proportion of energy intake in non-traditional eaters; however, these were consumed in significant amounts by both the groups (36 and 27% of total energy). Consumption of traditional foods is associated with greater diet quality and dietary adequacy. Efforts should be made to promote traditional and non-traditional foods of high-nutritional quality.

Comparison of Sellers's Awareness to Environmental Hygiene of Market Bulak, Market Klender and Market Rawamangun, East Jakarta

NASA Astrophysics Data System (ADS)

Maulidya, Hasana P.

2018-02-01

This research is motivated by the difference of market hygiene condition, where the market hygiene level is influenced by the environment around the market. In general, markets located near densely populated housing tend to be overlooked, while markets near elite housing tend to be clean. This condition is also influenced by marketers' awareness of market hygiene. If the market is near the elite neighbourhood, the level of awareness of sellers on cleanliness will be high. If the market is located in a densely populated area, sellers generally do not pay attention to cleanliness. The purpose of this research is to know the sellers's awareness of environmental cleanliness of Market Bulak, Klender Market and Rawamangun Market. Respondents in this study are sellers and buyers who make transactions in these 3 markets. This type of research is descriptive analysis with the method of observation and interview to 10 sellers in each market. Seller hygiene awareness are poor.

Use of the TLX ultracentrifuge for the isolation of different density lipoproteins and effects of freeze/thawing of human plasma before ultracentrifugation.

PubMed

Charlton-Menys, Valentine; Chobotova, Jelena; Durrington, Paul N

2008-01-01

Isolation of different density lipoproteins by ultracentrifugation can require lengthy centrifugation times and freeze/thawing of plasma may influence recovery. We isolated a range of lipoproteins using a preparative ultracentrifuge and the TLX micro-ultracentrifuge and determined the effect of freeze/thawing of plasma beforehand. In fresh plasma, there was no significant difference in results for small-dense low-density lipoprotein apolipoprotein B (LDL apoB) (density >1.044 g/mL) or cholesterol at density >1.006 g/mL. Freeze/thawing had no effect on closely correlated results for small-dense LDL apoB (r=0.85; p<0.0001) or high-density lipoprotein (r=0.93; p<0.0001). The TLX micro-ultracentrifuge is a reliable alternative to the preparative ultracentrifuge and freeze/thawing has only a small effect on small-dense LDL apoB or high-density lipoprotein cholesterol.

Immunogenicity is preferentially induced in sparse dendritic cell cultures.

PubMed

Nasi, Aikaterini; Bollampalli, Vishnu Priya; Sun, Meng; Chen, Yang; Amu, Sylvie; Nylén, Susanne; Eidsmo, Liv; Rothfuchs, Antonio Gigliotti; Réthi, Bence

2017-03-09

We have previously shown that human monocyte-derived dendritic cells (DCs) acquired different characteristics in dense or sparse cell cultures. Sparsity promoted the development of IL-12 producing migratory DCs, whereas dense cultures increased IL-10 production. Here we analysed whether the density-dependent endogenous breaks could modulate DC-based vaccines. Using murine bone marrow-derived DC models we show that sparse cultures were essential to achieve several key functions required for immunogenic DC vaccines, including mobility to draining lymph nodes, recruitment and massive proliferation of antigen-specific CD4+ T cells, in addition to their TH1 polarization. Transcription analyses confirmed higher commitment in sparse cultures towards T cell activation, whereas DCs obtained from dense cultures up-regulated immunosuppressive pathway components and genes suggesting higher differentiation plasticity towards osteoclasts. Interestingly, we detected a striking up-regulation of fatty acid and cholesterol biosynthesis pathways in sparse cultures, suggesting an important link between DC immunogenicity and lipid homeostasis regulation.

Prevalence of Mammographically Dense Breasts in the United States

PubMed Central

Gangnon, Ronald E.; Burt, Veronica; Trentham-Dietz, Amy; Hampton, John M.; Wellman, Robert D.; Kerlikowske, Karla; Miglioretti, Diana L.

2014-01-01

Background National legislation is under consideration that would require women with mammographically dense breasts to be informed of their breast density and encouraged to discuss supplemental breast cancer screening with their health care providers. The number of US women potentially affected by this legislation is unknown. Methods We determined the mammographic breast density distribution by age and body mass index (BMI) using data from 1518 599 mammograms conducted from 2007 through 2010 at mammography facilities in the Breast Cancer Surveillance Consortium (BCSC). We applied these breast density distributions to age- and BMI-specific counts of the US female population derived from the 2010 US Census and the National Health and Nutrition Examination Survey (NHANES) to estimate the number of US women with dense breasts. Results Overall, 43.3% (95% confidence interval [CI] = 43.1% to 43.4%) of women 40 to 74 years of age had heterogeneously or extremely dense breasts, and this proportion was inversely associated with age and BMI. Based on the age and BMI distribution of US women, we estimated that 27.6 million women (95% CI = 27.5 to 27.7 million) aged 40 to 74 years in the United States have heterogeneously or extremely dense breasts. Women aged 40 to 49 years (N = 12.3 million) accounted for 44.3% of this group. Conclusion The prevalence of dense breasts among US women of common breast cancer screening ages exceeds 25 million. Policymakers and healthcare providers should consider this large prevalence when debating breast density notification legislation and designing strategies to ensure that women who are notified have opportunities to evaluate breast cancer risk and discuss and pursue supplemental screening options if deemed appropriate. PMID:25217577

Application of Semiparametric Spline Regression Model in Analyzing Factors that In uence Population Density in Central Java

NASA Astrophysics Data System (ADS)

Sumantari, Y. D.; Slamet, I.; Sugiyanto

2017-06-01

Semiparametric regression is a statistical analysis method that consists of parametric and nonparametric regression. There are various approach techniques in nonparametric regression. One of the approach techniques is spline. Central Java is one of the most densely populated province in Indonesia. Population density in this province can be modeled by semiparametric regression because it consists of parametric and nonparametric component. Therefore, the purpose of this paper is to determine the factors that in uence population density in Central Java using the semiparametric spline regression model. The result shows that the factors which in uence population density in Central Java is Family Planning (FP) active participants and district minimum wage.

Dense Cores in Galaxies Out to z = 2.5 in SDSS, UltraVISTA, and the Five 3D-HST/CANDELS Fields

NASA Astrophysics Data System (ADS)

van Dokkum, Pieter G.; Bezanson, Rachel; van der Wel, Arjen; Nelson, Erica June; Momcheva, Ivelina; Skelton, Rosalind E.; Whitaker, Katherine E.; Brammer, Gabriel; Conroy, Charlie; Förster Schreiber, Natascha M.; Fumagalli, Mattia; Kriek, Mariska; Labbé, Ivo; Leja, Joel; Marchesini, Danilo; Muzzin, Adam; Oesch, Pascal; Wuyts, Stijn

2014-08-01

The dense interiors of massive galaxies are among the most intriguing environments in the universe. In this paper,we ask when these dense cores were formed and determine how galaxies gradually assembled around them. We select galaxies that have a stellar mass >3 × 1010 M ⊙ inside r = 1 kpc out to z = 2.5, using the 3D-HST survey and data at low redshift. Remarkably, the number density of galaxies with dense cores appears to have decreased from z = 2.5 to the present. This decrease is probably mostly due to stellar mass loss and the resulting adiabatic expansion, with some contribution from merging. We infer that dense cores were mostly formed at z > 2.5, consistent with their largely quiescent stellar populations. While the cores appear to form early, the galaxies in which they reside show strong evolution: their total masses increase by a factor of 2-3 from z = 2.5 to z = 0 and their effective radii increase by a factor of 5-6. As a result, the contribution of dense cores to the total mass of the galaxies in which they reside decreases from ~50% at z = 2.5 to ~15% at z = 0. Because of their early formation, the contribution of dense cores to the total stellar mass budget of the universe is a strong function of redshift. The stars in cores with M 1 kpc > 3 × 1010 M ⊙ make up ~0.1% of the stellar mass density of the universe today but 10%-20% at z ~ 2, depending on their initial mass function. The formation of these cores required the conversion of ~1011 M ⊙ of gas into stars within ~1 kpc, while preventing significant star formation at larger radii.

Potential impact of legislation mandating breast density notification: benefits, harms, and cost effectiveness of supplemental ultrasound screening

PubMed Central

Sprague, Brian L.; Stout, Natasha K.; Schechter, Clyde; van Ravesteyn, Nicolien T.; Cevik, Mucahit; Alagoz, Oguzhan; Lee, Christoph I.; van den Broek, Jeroen J.; Miglioretti, Diana L.; Mandelblatt, Jeanne S.; de Koning, Harry J.; Kerlikowske, Karla; Lehman, Constance D.; Tosteson, Anna N. A.

2014-01-01

Background At least nineteen states have laws that require telling women with dense breasts and a negative screening mammogram to consider supplemental screening. The most readily available supplemental screening modality is ultrasound, yet little is known about its effectiveness. Objective To evaluate the benefits, harms, and cost-effectiveness of supplemental ultrasound screening for women with dense breasts. Design Comparative modeling with 3 validated simulation models. Data Sources Surveillance, Epidemiology, and End Results Program; Breast Cancer Surveillance Consortium; the medical literature. Target Population A contemporary cohort of women eligible for routine screening. Time Horizon Lifetime. Perspective Payer. Interventions Supplemental ultrasound screening for women with dense breasts following a negative screening mammogram. Outcome Measures Breast cancer deaths averted, quality-adjusted life years (QALYs) gained, false positive ultrasound biopsy recommendations, costs, costs per QALY gained. Results of Base-Case Analysis Supplemental ultrasound screening after a negative mammogram for women aged 50–74 with heterogeneously or extremely dense breasts averted 0.36 additional breast cancer deaths (range across models: 0.14–0.75), gained 1.7 QALYs (0.9–4.7), and resulted in 354 false-positive ultrasound biopsy recommendations (345–421) per 1000 women with dense breasts compared with biennial screening by mammography alone. The cost-effectiveness ratio was $325,000 per QALY gained ($112,000-$766,000). Restricting supplemental ultrasound screening to women with extremely dense breasts cost $246,000 per QALY gained ($74,000-$535,000). Results of Sensitivity Analysis The conclusions were not sensitive to ultrasound performance characteristics, screening frequency, or starting age. Limitations Provider costs for coordinating supplemental ultrasound were not considered. Conclusions Supplemental ultrasound screening for women with dense breasts undergoing screening mammography would substantially increase costs while producing relatively small benefits in breast cancer deaths averted and QALYs gained. Primary Funding Source National Institutes of Health PMID:25486550

C3 glomerulonephritis and dense deposit disease share a similar disease course in a large United States cohort of patients with C3 glomerulopathy.

PubMed

Bomback, Andrew S; Santoriello, Dominick; Avasare, Rupali S; Regunathan-Shenk, Renu; Canetta, Pietro A; Ahn, Wooin; Radhakrishnan, Jai; Marasa, Maddalena; Rosenstiel, Paul E; Herlitz, Leal C; Markowitz, Glen S; D'Agati, Vivette D; Appel, Gerald B

2018-04-01

C3 glomerulonephritis (C3GN) and dense deposit disease comprise the two classes of C3 glomerulopathy. Studies from Europe and Asia have aided our understanding of this recently defined disorder, but whether these data apply to a diverse United States patient population remains unclear. We, therefore, reviewed clinical and histopathological data, including generation of a C3 Glomerulopathy Histologic Index to score biopsy activity and chronicity, to determine predictors of progression to end-stage renal disease (ESRD) and advanced chronic kidney disease (CKD) in 111 patients (approximately 35% non-white) with C3 glomerulopathy: 87 with C3GN and 24 with dense deposit disease. Complement-associated gene variants and autoantibodies were detected in 24% and 35% of screened patients, respectively. Our C3 Glomerulopathy Histologic Index denoted higher activity in patients with C3GN and higher chronicity in patients with dense deposit disease. Over an average of 72 months of follow-up, remission occurred in 38% of patients with C3GN and 25% of patients with dense deposit disease. Progression to late-stage CKD and ESRD was common, with no differences between C3GN (39%) and dense deposit disease (42%). In multivariable models, the strongest predictors for progression were estimated glomerular filtration rate at diagnosis (clinical variables model) and tubular atrophy/interstitial fibrosis (histopathology variables model). Using our C3 Glomerulopathy Histologic Index, both total activity and total chronicity scores emerged as the strongest predictors of progression. Thus, in a large, diverse American cohort of patients with C3 glomerulopathy, there is a high rate of progression to CKD and ESRD with no differences between C3GN and dense deposit disease. Copyright © 2017 International Society of Nephrology. Published by Elsevier Inc. All rights reserved.

Revealing the selection history of adaptive loci using genome-wide scans for selection: an example from domestic sheep.

PubMed

Rochus, Christina Marie; Tortereau, Flavie; Plisson-Petit, Florence; Restoux, Gwendal; Moreno-Romieux, Carole; Tosser-Klopp, Gwenola; Servin, Bertrand

2018-01-23

One of the approaches to detect genetics variants affecting fitness traits is to identify their surrounding genomic signatures of past selection. With established methods for detecting selection signatures and the current and future availability of large datasets, such studies should have the power to not only detect these signatures but also to infer their selective histories. Domesticated animals offer a powerful model for these approaches as they adapted rapidly to environmental and human-mediated constraints in a relatively short time. We investigated this question by studying a large dataset of 542 individuals from 27 domestic sheep populations raised in France, genotyped for more than 500,000 SNPs. Population structure analysis revealed that this set of populations harbour a large part of European sheep diversity in a small geographical area, offering a powerful model for the study of adaptation. Identification of extreme SNP and haplotype frequency differences between populations listed 126 genomic regions likely affected by selection. These signatures revealed selection at loci commonly identified as selection targets in many species ("selection hotspots") including ABCG2, LCORL/NCAPG, MSTN, and coat colour genes such as ASIP, MC1R, MITF, and TYRP1. For one of these regions (ABCG2, LCORL/NCAPG), we could propose a historical scenario leading to the introgression of an adaptive allele into a new genetic background. Among selection signatures, we found clear evidence for parallel selection events in different genetic backgrounds, most likely for different mutations. We confirmed this allelic heterogeneity in one case by resequencing the MC1R gene in three black-faced breeds. Our study illustrates how dense genetic data in multiple populations allows the deciphering of evolutionary history of populations and of their adaptive mutations.

Parametric Human Body Reconstruction Based on Sparse Key Points.

PubMed

Cheng, Ke-Li; Tong, Ruo-Feng; Tang, Min; Qian, Jing-Ye; Sarkis, Michel

2016-11-01

We propose an automatic parametric human body reconstruction algorithm which can efficiently construct a model using a single Kinect sensor. A user needs to stand still in front of the sensor for a couple of seconds to measure the range data. The user's body shape and pose will then be automatically constructed in several seconds. Traditional methods optimize dense correspondences between range data and meshes. In contrast, our proposed scheme relies on sparse key points for the reconstruction. It employs regression to find the corresponding key points between the scanned range data and some annotated training data. We design two kinds of feature descriptors as well as corresponding regression stages to make the regression robust and accurate. Our scheme follows with dense refinement where a pre-factorization method is applied to improve the computational efficiency. Compared with other methods, our scheme achieves similar reconstruction accuracy but significantly reduces runtime.

The impact of urbanization and population density on childhood Plasmodium falciparum parasite prevalence rates in Africa.

PubMed

Kabaria, Caroline W; Gilbert, Marius; Noor, Abdisalan M; Snow, Robert W; Linard, Catherine

2017-01-26

Although malaria has been traditionally regarded as less of a problem in urban areas compared to neighbouring rural areas, the risk of malaria infection continues to exist in densely populated, urban areas of Africa. Despite the recognition that urbanization influences the epidemiology of malaria, there is little consensus on urbanization relevant for malaria parasite mapping. Previous studies examining the relationship between urbanization and malaria transmission have used products defining urbanization at global/continental scales developed in the early 2000s, that overestimate actual urban extents while the population estimates are over 15 years old and estimated at administrative unit level. This study sought to discriminate an urbanization definition that is most relevant for malaria parasite mapping using individual level malaria infection data obtained from nationally representative household-based surveys. Boosted regression tree (BRT) modelling was used to determine the effect of urbanization on malaria transmission and if this effect varied with urbanization definition. In addition, the most recent high resolution population distribution data was used to determine whether population density had significant effect on malaria parasite prevalence and if so, could population density replace urban classifications in modelling malaria transmission patterns. The risk of malaria infection was shown to decline from rural areas through peri-urban settlements to urban central areas. Population density was found to be an important predictor of malaria risk. The final boosted regression trees (BRT) model with urbanization and population density gave the best model fit (Tukey test p value <0.05) compared to the models with urbanization only. Given the challenges in uniformly classifying urban areas across different countries, population density provides a reliable metric to adjust for the patterns of malaria risk in densely populated urban areas. Future malaria risk models can, therefore, be improved by including both population density and urbanization which have both been shown to have significant impact on malaria risk in this study.

Diagnostic accuracy of contrast-enhanced spectral mammography in comparison to conventional full-field digital mammography in a population of women with dense breasts.

PubMed

Mori, Miki; Akashi-Tanaka, Sadako; Suzuki, Satoko; Daniels, Murasaki Ikeda; Watanabe, Chie; Hirose, Masanori; Nakamura, Seigo

2017-01-01

Contrast-enhanced spectral mammography to compare clinical efficacy of contrast-enhanced spectral mammography (CESM) and conventional digital mammography (MMG) with histopathology as gold standard in dense breasts. A total of 143 breasts of 72 women who underwent CESM and MMG between 2011 and 2014 at Showa University Hospital were analyzed. 129 (90.2 %) of 143 breasts revealed dense breasts on MMG. 58 (40.6 %) of 143 breasts were diagnosed with breast cancer at histopathology. The remaining 85 breasts were diagnosed with benign findings after image assessments and/or core needle biopsy. CESM revealed 8 false-negative cases among 58 breast cancer cases (sensitivity 86.2 %) and 5 false-positive cases (specificity 94.1 %). Accuracy was 90.9 %. Conventional MMG was assessed true positive in 31 of 58 breast cancer cases (sensitivity 53.4 %) and false positive in 12 cases (specificity 85.9 %). Accuracy was 72.7 %. Sensitivity (p < 0.001), specificity (p = 0.016) and accuracy (p < 0.001) were significantly higher on CESM compared to MMG. MMG missed malignancy in 27 breasts. Of these, 25 were dense breasts. Of these 25, 20 (80.0 %) breasts were positive on CESM. These findings suggest that CESM offers superior clinical performance compared to MMG. Use of CESM may decrease false negatives especially for women with dense breasts.

Anticipatory flexibility: larval population density in moths determines male investment in antennae, wings and testes.

PubMed

Johnson, Tamara L; Symonds, Matthew R E; Elgar, Mark A

2017-11-15

Developmental plasticity provides individuals with a distinct advantage when the reproductive environment changes dramatically. Variation in population density, in particular, can have profound effects on male reproductive success. Females may be easier to locate in dense populations, but there may be a greater risk of sperm competition. Thus, males should invest in traits that enhance fertilization success over traits that enhance mate location. Conversely, males in less dense populations should invest more in structures that will facilitate mate location. In Lepidoptera, this may result in the development of larger antennae to increase the likelihood of detecting female sex pheromones, and larger wings to fly more efficiently. We explored the effects of larval density on adult morphology in the gum-leaf skeletonizer moth, Uraba lugens , by manipulating both the number of larvae and the size of the rearing container. This experimental arrangement allowed us to reveal the cues used by larvae to assess whether absolute number or density influences adult responses. Male investment in testes size depended on the number of individuals, while male investment in wings and antennae depended upon larval density. By contrast, the size of female antennae and wings were influenced by an interaction of larval number and container size. This study demonstrates that male larvae are sensitive to cues that may reveal adult population density, and adjust investment in traits associated with fertilization success and mate detection accordingly. © 2017 The Author(s).

Uncovering the hidden iceberg structure of the Galactic halo

NASA Astrophysics Data System (ADS)

Moss, Vanessa A.; Di Teodoro, Enrico M.; McClure-Griffiths, Naomi M.; Lockman, Felix; Pisano, D. J.; Price, Daniel; Rees, Glen

2018-01-01

How the Milky Way gets its gas and keeps its measured star formation rate going are both long-standing mysteries in Galactic studies, with important implications for galaxy evolution across the Universe. I will present our recent discovery of two populations of neutral hydrogen (HI) in the halo of the Milky Way: 1) a narrow line-width dense population typical of the majority of bright high velocity cloud (HVC) components, and 2) a fainter, broad line-width diffuse population that aligns well with the population found in very sensitive pointings such as in Lockman et al. (2002). From our existing data, we concluded that the diffuse population likely outweighs the dense HI by a factor of 3. This discovery of diffuse HI, which appears to be prevalent throughout the halo, takes us closer to solving the Galactic mystery of accretion and reveals a gaseous neutral halo hidden from the view of most large-scale surveys. We are currently carrying out deep Parkes observations to investigate these results further, in order to truly uncover the nature of the diffuse HI and determine whether our 3:1 ratio (based on the limited existing data) is consistent with what is seen when Parkes and the 140 ft Green Bank telescope are employed at comparable sensitivity. With these data, through a combination of both known and new sightline measurements, we aim to reveal the structure of the Galactic halo in more detail than ever before.

A New Population Estimate for the Florida Scrub Jay on Merritt Island National Wildlife Refuge

NASA Technical Reports Server (NTRS)

Breininger, David R.

1989-01-01

The variable circular plot method was used to sample avifauna within different vegetation types determined from aerial imagery. The Florida Scrub Jay (Aphelocoma coerulescens coerulescens) population was estimated to range between 1,415 and 3,603 birds. Approximately half of the scrub and slash pine habitat appeared to be unused by Florida Scrub Jay, probably because the slash pine cover was too dense or the oak cover was too sparse. Results from the study suggest that the entire state population may be much lower than believed because the size of two of the three largest populations may have been overestimated.

The MALATANG Survey: The L GAS–L IR Correlation on Sub-kiloparsec Scale in Six Nearby Star-forming Galaxies as Traced by HCN J = 4 → 3 and HCO+ J = 4 → 3

NASA Astrophysics Data System (ADS)

Tan, Qing-Hua; Gao, Yu; Zhang, Zhi-Yu; Greve, Thomas R.; Jiang, Xue-Jian; Wilson, Christine D.; Yang, Chen-Tao; Bemis, Ashley; Chung, Aeree; Matsushita, Satoki; Shi, Yong; Ao, Yi-Ping; Brinks, Elias; Currie, Malcolm J.; Davis, Timothy A.; de Grijs, Richard; Ho, Luis C.; Imanishi, Masatoshi; Kohno, Kotaro; Lee, Bumhyun; Parsons, Harriet; Rawlings, Mark G.; Rigopoulou, Dimitra; Rosolowsky, Erik; Bulger, Joanna; Chen, Hao; Chapman, Scott C.; Eden, David; Gear, Walter K.; Gu, Qiu-Sheng; He, Jin-Hua; Jiao, Qian; Liu, Dai-Zhong; Liu, Li-Jie; Li, Xiao-Hu; Michałowski, Michał J.; Nguyen-Luong, Quang; Qiu, Jian-Jie; Smith, Matthew W. L.; Violino, Giulio; Wang, Jian-Fa; Wang, Jun-Feng; Wang, Jun-Zhi; Yeh, Sherry; Zhao, Ying-He; Zhu, Ming

2018-06-01

We present {HCN} J=4\\to 3 and {HCO}}+ J=4\\to 3 maps of six nearby star-forming galaxies, NGC 253, NGC 1068, IC 342, M82, M83, and NGC 6946, obtained with the James Clerk Maxwell Telescope as part of the MALATANG survey. All galaxies were mapped in the central 2‧ × 2‧ region at 14″ (FWHM) resolution (corresponding to linear scales of ∼0.2–1.0 kpc). The L IR–L‧dense relation, where the dense gas is traced by the {HCN} J=4\\to 3 and the {HCO}}+ J=4\\to 3 emission, measured in our sample of spatially resolved galaxies is found to follow the linear correlation established globally in galaxies within the scatter. We find that the luminosity ratio, L IR/L‧dense, shows systematic variations with L IR within individual spatially resolved galaxies, whereas the galaxy-integrated ratios vary little. A rising trend is also found between L IR/L‧dense ratio and the warm-dust temperature gauged by the 70 μm/100 μm flux ratio. We find that the luminosity ratios of IR/HCN (4–3) and IR/HCO+ (4–3), which can be taken as a proxy for the star formation efficiency (SFE) in the dense molecular gas (SFEdense), appear to be nearly independent of the dense gas fraction (f dense) for our sample of galaxies. The SFE of the total molecular gas (SFEmol) is found to increase substantially with f dense when combining our data with those on local (ultra)luminous infrared galaxies and high-z quasars. The mean L{{\\prime} }HCN(4{--}3)}/L{{\\prime} }HCO}+(4{--}3)} line ratio measured for the six targeted galaxies is 0.9 ± 0.6. No significant correlation is found for the L{{\\prime} }HCN(4{--}3)}/L{{\\prime} }HCO}+(4{--}3)} ratio with the star formation rate as traced by L IR, nor with the warm-dust temperature, for the different populations of galaxies.

Genetic differences in the two main groups of the Japanese population based on autosomal SNPs and haplotypes.

PubMed

Yamaguchi-Kabata, Yumi; Tsunoda, Tatsuhiko; Kumasaka, Natsuhiko; Takahashi, Atsushi; Hosono, Naoya; Kubo, Michiaki; Nakamura, Yusuke; Kamatani, Naoyuki

2012-05-01

Although the Japanese population has a rather low genetic diversity, we recently confirmed the presence of two main clusters (the Hondo and Ryukyu clusters) through principal component analysis of genome-wide single-nucleotide polymorphism (SNP) genotypes. Understanding the genetic differences between the two main clusters requires further genome-wide analyses based on a dense SNP set and comparison of haplotype frequencies. In the present study, we determined haplotypes for the Hondo cluster of the Japanese population by detecting SNP homozygotes with 388,591 autosomal SNPs from 18,379 individuals and estimated the haplotype frequencies. Haplotypes for the Ryukyu cluster were inferred by a statistical approach using the genotype data from 504 individuals. We then compared the haplotype frequencies between the Hondo and Ryukyu clusters. In most genomic regions, the haplotype frequencies in the Hondo and Ryukyu clusters were very similar. However, in addition to the human leukocyte antigen region on chromosome 6, other genomic regions (chromosomes 3, 4, 5, 7, 10 and 12) showed dissimilarities in haplotype frequency. These regions were enriched for genes involved in the immune system, cell-cell adhesion and the intracellular signaling cascade. These differentiated genomic regions between the Hondo and Ryukyu clusters are of interest because they (1) should be examined carefully in association studies and (2) likely contain genes responsible for morphological or physiological differences between the two groups.

Rapid decadal evolution in the groundwater arsenic content of Kolkata, India and its correlation with the practices of her dwellers.

PubMed

Malakar, Arindam; Islam, Samirul; Ali, Md Ashif; Ray, Sugata

2016-10-01

Increasing arsenic contamination in the groundwater is one of the biggest environmental challenges that the Bengal delta is facing today. Groundwater is still the main source of water for a large number of population in this region and therefore, significant presence of toxic arsenic has a direct consequence on human lives here. Moreover, arsenic also enters into the food chain through the consumed agricultural products grown in this area. Therefore, acquiring knowledge about the ever-changing map of arsenic contamination and employing adequate protective measures are of utmost importance. Here, we present a comprehensive municipal ward-wise map of the arsenic content of the shallow groundwater table of Kolkata-the most important and highly population dense city of the delta. Comparison with previously available data reveals a rapid change and the grim situation for the city. Our study suggests that it should be an immediate task of the administration to extend treated water service to the whole population of the city for direct consumption, and artificial recharge and maximum rainwater replenishment need to be taken up with utmost urgency to avoid intrusion of toxicity in biological food chains via agricultural products. We hope our study would drive the city planners to reconsider the existing urbanization and development plans of all the cities, placed over arsenic-contaminated groundwater aquifers.

Plant invasion: Another threat to the São Paulo Marsh Antwren (Formicivora paludicola), a species on the verge of extinction

PubMed Central

Rêgo, Marco Antonio; Silveira, Luís Fábio; Itoh, Akira

2017-01-01

During the past 100 years in densely populated south-eastern Brazil, wetlands have been severely transformed due to urbanization, agriculture and mining. The recently discovered São Paulo Marsh Antwren (Formicivora paludicola) is endemic to these wetlands, and is listed as “Critically Endangered” by the IUCN. The species is only found in an area of 1.42 km2, it has a sparse and fragmented distribution, low dispersal capacity, and has probably lost around 300 km2 of habitat in the past 100 years. Furthermore, very little is known about F. paludicola natural history, and so it is difficult to construct a robust conservation plan. Using Kernel home range estimations and the Adjusted-SD/Torus Shift test (a novel tool for animal-habitat association studies), we showed that the species avoids patches of the alien invasive ginger lily (Hedychium coronarium). Given the high density of their population (3.6 mature individuals/ha), F. paludicola could thrive in relatively small areas of suitable wetlands protected from human occupation and water contamination, however special attention should be paid to biological invasions, which may represent a serious threat to the remaining populations. Protecting a few small wetlands used by F. paludicola would be an important step towards general conservation and restoration of Atlantic Forest wetlands and its endemic endangered species. PMID:29281668

Sinks without borders: Snowshoe hare dynamics in a complex landscape

USGS Publications Warehouse

Griffin, Paul C.; Mills, L. Scott

2009-01-01

A full understanding of population dynamics of wide-ranging animals should account for the effects that movement and habitat use have on individual contributions to population growth or decline. Quantifying the per-capita, habitat-specific contribution to population growth can clarify the value of different patch types, and help to differentiate population sources from population sinks. Snowshoe hares, Lepus americanus, routinely use various habitat types in the landscapes they inhabit in the contiguous US, where managing forests for high snowshoe hare density is a priority for conservation of Canada lynx, Lynx canadensis. We estimated density and demographic rates via mark–recapture live trapping and radio-telemetry within four forest stand structure (FSS) types at three study areas within heterogeneous managed forests in western Montana. We found support for known fate survival models with time-varying individual covariates representing the proportion of locations in each of the FSS types, with survival rates decreasing as use of open young and open mature FSS types increased. The per-capita contribution to overall population growth increased with use of the dense mature or dense young FSS types and decreased with use of the open young or open mature FSS types, and relatively high levels of immigration appear to be necessary to sustain hares in the open FSS types. Our results support a conceptual model for snowshoe hares in the southern range in which sink habitats (open areas) prevent the buildup of high hare densities. More broadly, we use this system to develop a novel approach to quantify demographic sources and sinks for animals making routine movements through complex fragmented landscapes.

Phytochemical Properties and Nutrigenomic Implications of Yacon as a Potential Source of Prebiotic: Current Evidence and Future Directions

PubMed Central

Cao, Yang; Zhang, Hongxia; Jin, Yifan; Zhang, Yihe; Hayford, Frank

2018-01-01

The human gut is densely populated with diverse microbial communities that are essential to health. Prebiotics and fiber have been shown to possess the ability to modulate the gut microbiota. One of the plants being considered as a potential source of prebiotic is yacon. Yacon is an underutilized plant consumed as a traditional root-based fruit in South America. Yacon mainly contains fructooligosaccharides (FOS) and inulin. Therefore, it has bifidogenic benefits for gut health, because FOS are not easily broken down by digestive enzymes. Bioactive chemical compounds and extracts isolated from yacon have been studied for their various nutrigenomic properties, including as a prebiotic for intestinal health and their antimicrobial and antioxidant effects. This article reviewed scientific studies regarding the bioactive chemical compounds and nutrigenomic properties of extracts and isolated compounds from yacon. These findings may help in further research to investigate yacon-based nutritional products. Yacon can be considered a potential prebiotic source and a novel functional food. However, more detailed epidemiological, animal, and human clinical studies, particularly mechanism-based and phytopharmacological studies, are lacking for the development of evidence-based functional food products. PMID:29649123

Phytochemical Properties and Nutrigenomic Implications of Yacon as a Potential Source of Prebiotic: Current Evidence and Future Directions.

PubMed

Cao, Yang; Ma, Zheng Feei; Zhang, Hongxia; Jin, Yifan; Zhang, Yihe; Hayford, Frank

2018-04-12

The human gut is densely populated with diverse microbial communities that are essential to health. Prebiotics and fiber have been shown to possess the ability to modulate the gut microbiota. One of the plants being considered as a potential source of prebiotic is yacon. Yacon is an underutilized plant consumed as a traditional root-based fruit in South America. Yacon mainly contains fructooligosaccharides (FOS) and inulin. Therefore, it has bifidogenic benefits for gut health, because FOS are not easily broken down by digestive enzymes. Bioactive chemical compounds and extracts isolated from yacon have been studied for their various nutrigenomic properties, including as a prebiotic for intestinal health and their antimicrobial and antioxidant effects. This article reviewed scientific studies regarding the bioactive chemical compounds and nutrigenomic properties of extracts and isolated compounds from yacon. These findings may help in further research to investigate yacon-based nutritional products. Yacon can be considered a potential prebiotic source and a novel functional food. However, more detailed epidemiological, animal, and human clinical studies, particularly mechanism-based and phytopharmacological studies, are lacking for the development of evidence-based functional food products.

Flexible architecture: bamboo as a tool for children to play in urban kampung

NASA Astrophysics Data System (ADS)

Susanto, D.; Widyarko; Ilmiani, A. N.

2018-03-01

Due to the dense population and increase of development, urban kampung in Indonesia is facing a problem of limited children’s play spaces. Flexible architecture with its movable principle is expected to be a solution by creating children’s playing tool that is built among the dense urban kampung. Bamboo is the staple material because it is local, able to regenerate quickly, lightweight, and affordable. By using the exploratory method, this research tries to reveal the previously hidden aspects by evaluating all processes of design-build of three created children’s playing tools. These playing tools can be built in the kampung after three processes of apart-and-reassemble. However, there are several questions which need to be discussed further; the right configuration between the component and the joint of the bamboo, to make apart-and-reassemble process more effective in a dense urban kampung, and also how to make bamboo’s structure able to survive better under rainy seasons and surface humidity.

Immunohistochemical localization of alpha and beta adrenergic receptors in the human nasal turbinate.

PubMed

Shirasaki, Hideaki; Kanaizumi, Etsuko; Himi, Tetsuo

2016-06-01

Adrenergic receptors (ARs) include four general types (α1, α2, β1 and β2), which are found in different target tissues. α-AR agonists are commonly used for decongestant therapy of upper airway diseases. In order to clarify the roles of AR subtypes in the upper airways, we investigated the localization of these receptors by immunohistochemistry. Human turbinates were obtained after turbinectomy from 12 patients with nasal obstruction refractory to medical therapy. The specific cells expressing α- and β-AR proteins were identified by immunostaining using an anti-human AR subtype-specific antibodies (α1A-, α1D-, α2C- and β2-ARs) antibody. Immunohistochemical analysis revealed that immunoreactivities for α1D- and β2-ARs were densely distributed in submucosal glands. In contrast, immunoreactivities for α1A- and 2C-ARs were densely distributed in vascular smooth muscle. Our results suggested that adrenergic receptor (AR) subtypes had different roles in upper airway diseases, such as allergic rhinitis and nonallergic rhinitis. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

Enhancing genomic prediction with genome-wide association studies in multiparental maize populations

USDA-ARS?s Scientific Manuscript database

Genome-wide association mapping using dense marker sets has identified some nucleotide variants affecting complex traits which have been validated with fine-mapping and functional analysis. Many sequence variants associated with complex traits in maize have small effects and low repeatability, howev...

Habitat use by mountain quail in Northern California

Treesearch

Leonard A. Brennan; R. J. Gutierrez

1987-01-01

We studied habitat use by Mountain Quail (Oreortyx pictus) at four sites in northern California. Vegetative cover types (macrohabitats) were used in proportion to availability. Significant microhabitat variables which distinguished used from available microhabitat structure included proximity to water and tall, dense shrubs. Mountain Quail population...

Ixodid ticks in the megapolis of Kyiv, Ukraine

USDA-ARS?s Scientific Manuscript database

The Ixodidae include the most common tick species encountered in Europe. The ticks transmit a variety of bacterial and protozoan agents of medical and veterinary significance. The aim of the current work was to investigate distribution of Ixodidae ticks in Kyiv, the largest and most densely populate...

LINKING HABITAT CHANGE AND NUTRIENT DYNAMICS: COMPARISON OF FOOD WEBS AND NITROGEN FLUXES IN BURROWING SHRIMP- AND OYSTER-DOMINATED HABITATS

EPA Science Inventory

Endemic thalassinid burrowing shrimps are simultaneously dominant ecosystem engineering species and economic pests within Pacific estuaries. Dense populations of two shrimps (Neotrypaea californiensis and Upogebia pugettensis) commonly occupy >75% of intertidal and shallow subti...

Generation 2030/Africa

ERIC Educational Resources Information Center

You, Danzhen; Hug, Lucia; Anthony, David

2014-01-01

Until relatively recently, much of Africa has been among the economically least developed and least densely populated places on earth, replete with villages and rural communities. Africa is changing rapidly, in its economy, trade and investment; in climate change; in conflict and stability; in urbanization, migration patterns, and most of all in…

A Dense Poly(ethylene glycol) Coating Improves Penetration of Large Polymeric Nanoparticles within Brain Tissue

PubMed Central

Nance, Elizabeth A.; Woodworth, Graeme F.; Sailor, Kurt A.; Shih, Ting-Yu; Xu, Qingguo; Swaminathan, Ganesh; Xiang, Dennis; Eberhart, Charles; Hanes, Justin

2013-01-01

Prevailing opinion suggests that only substances up to 64 nm in diameter can move at appreciable rates through the brain extracellular space (ECS). This size range is large enough to allow diffusion of signaling molecules, nutrients, and metabolic waste products, but too small to allow efficient penetration of most particulate drug delivery systems and viruses carrying therapeutic genes, thereby limiting effectiveness of many potential therapies. We analyzed the movements of nanoparticles of various diameters and surface coatings within fresh human and rat brain tissue ex vivo and mouse brain in vivo. Nanoparticles as large as 114-nm in diameter diffused within the human and rat brain, but only if they were densely coated with poly(ethylene glycol) (PEG). Using these minimally adhesive PEG-coated particles, we estimated that human brain tissue ECS has some pores larger than 200 nm, and that more than one-quarter of all pores are ≥100 nm. These findings were confirmed in vivo in mice, where 40- and 100-nm, but not 200-nm, nanoparticles, spread rapidly within brain tissue, only if densely coated with PEG. Similar results were observed in rat brain tissue with paclitaxel-loaded biodegradable nanoparticles of similar size (85 nm) and surface properties. The ability to achieve brain penetration with larger nanoparticles is expected to allow more uniform, longer-lasting, and effective delivery of drugs within the brain, and may find use in the treatment of brain tumors, stroke, neuroinflammation, and other brain diseases where the blood-brain barrier is compromised or where local delivery strategies are feasible. PMID:22932224

Does Population Density and Neighborhood Deprivation Predict Schizophrenia? A Nationwide Swedish Family-Based Study of 2.4 Million Individuals

PubMed Central

Sariaslan, Amir; Larsson, Henrik; D’Onofrio, Brian; Långström, Niklas; Fazel, Seena; Lichtenstein, Paul

2015-01-01

People living in densely populated and socially disorganized areas have higher rates of psychiatric morbidity, but the potential causal status of such factors is uncertain. We used nationwide Swedish longitudinal registry data to identify all children born 1967–1989 (n = 2361585), including separate datasets for all cousins (n = 1715059) and siblings (n = 1667894). The nature of the associations between population density and neighborhood deprivation and individual risk for a schizophrenia diagnosis was investigated while adjusting for unobserved familial risk factors (through cousin and sibling comparisons) and then compared with similar associations for depression. We generated familial pedigree structures using the Multi-Generation Registry and identified study participants with schizophrenia and depression using the National Patient Registry. Fixed-effects logistic regression models were used to study within-family estimates. Population density, measured as ln(population size/km2), at age 15 predicted subsequent schizophrenia in the population (OR = 1.10; 95% CI: 1.09; 1.11). Unobserved familial risk factors shared by cousins within extended families attenuated the association (1.06; 1.03; 1.10), and the link disappeared entirely within nuclear families (1.02; 0.97; 1.08). Similar results were found for neighborhood deprivation as predictor and for depression as outcome. Sensitivity tests demonstrated that timing and accumulation effects of the exposures (mean scores across birth, ages 1–5, 6–10, and 11–15 years) did not alter the findings. Excess risks of psychiatric morbidity, particularly schizophrenia, in densely populated and socioeconomically deprived Swedish neighborhoods appear, therefore, to result primarily from unobserved familial selection factors. Previous studies may have overemphasized the etiological importance of these environmental factors. PMID:25053652

Where to nest? Ecological determinants of chimpanzee nest abundance and distribution at the habitat and tree species scale.

PubMed

Carvalho, Joana S; Meyer, Christoph F J; Vicente, Luis; Marques, Tiago A

2015-02-01

Conversion of forests to anthropogenic land-uses increasingly subjects chimpanzee populations to habitat changes and concomitant alterations in the plant resources available to them for nesting and feeding. Based on nest count surveys conducted during the dry season, we investigated nest tree species selection and the effect of vegetation attributes on nest abundance of the western chimpanzee, Pan troglodytes verus, at Lagoas de Cufada Natural Park (LCNP), Guinea-Bissau, a forest-savannah mosaic widely disturbed by humans. Further, we assessed patterns of nest height distribution to determine support for the anti-predator hypothesis. A zero-altered generalized linear mixed model showed that nest abundance was negatively related to floristic diversity (exponential form of the Shannon index) and positively with the availability of smaller-sized trees, reflecting characteristics of dense-canopy forest. A positive correlation between nest abundance and floristic richness (number of plant species) and composition indicated that species-rich open habitats are also important in nest site selection. Restricting this analysis to feeding trees, nest abundance was again positively associated with the availability of smaller-sized trees, further supporting the preference for nesting in food tree species from dense forest. Nest tree species selection was non-random, and oil palms were used at a much lower proportion (10%) than previously reported from other study sites in forest-savannah mosaics. While this study suggests that human disturbance may underlie the exclusive arboreal nesting at LCNP, better quantitative data are needed to determine to what extent the construction of elevated nests is in fact a response to predators able to climb trees. Given the importance of LCNP as refuge for Pan t. verus our findings can improve conservation decisions for the management of this important umbrella species as well as its remaining suitable habitats. © 2014 Wiley Periodicals, Inc.

Quantitative breast MRI radiomics for cancer risk assessment and the monitoring of high-risk populations

NASA Astrophysics Data System (ADS)

Mendel, Kayla R.; Li, Hui; Giger, Maryellen L.

2016-03-01

Breast density is routinely assessed qualitatively in screening mammography. However, it is challenging to quantitatively determine a 3D density from a 2D image such as a mammogram. Furthermore, dynamic contrast enhanced magnetic resonance imaging (DCE-MRI) is used more frequently in the screening of high-risk populations. The purpose of our study is to segment parenchyma and to quantitatively determine volumetric breast density on pre-contrast axial DCE-MRI images (i.e., non-contrast) using a semi-automated quantitative approach. In this study, we retroactively examined 3D DCE-MRI images taken for breast cancer screening of a high-risk population. We analyzed 66 cases with ages between 28 and 76 (mean 48.8, standard deviation 10.8). DCE-MRIs were obtained on a Philips 3.0 T scanner. Our semi-automated DCE-MRI algorithm includes: (a) segmentation of breast tissue from non-breast tissue using fuzzy cmeans clustering (b) separation of dense and fatty tissues using Otsu's method, and (c) calculation of volumetric density as the ratio of dense voxels to total breast voxels. We examined the relationship between pre-contrast DCE-MRI density and clinical BI-RADS density obtained from radiology reports, and obtained a statistically significant correlation [Spearman ρ-value of 0.66 (p < 0.0001)]. Our method within precision medicine may be useful for monitoring high-risk populations.

Podosomes, But Not the Maturation Status, Determine the Protease-Dependent 3D Migration in Human Dendritic Cells.

PubMed

Cougoule, Céline; Lastrucci, Claire; Guiet, Romain; Mascarau, Rémi; Meunier, Etienne; Lugo-Villarino, Geanncarlo; Neyrolles, Olivier; Poincloux, Renaud; Maridonneau-Parini, Isabelle

2018-01-01

Dendritic cells (DC) are professional Antigen-Presenting Cells scattered throughout antigen-exposed tissues and draining lymph nodes, and survey the body for pathogens. Their ability to migrate through tissues, a 3D environment, is essential for an effective immune response. Upon infection, recognition of Pathogen-Associated Molecular Patterns (PAMP) by Toll-like receptors (TLR) triggers DC maturation. Mature DC (mDC) essentially use the protease-independent, ROCK-dependent amoeboid mode in vivo , or in collagen matrices in vitro . However, the mechanisms of 3D migration used by human immature DC (iDC) are still poorly characterized. Here, we reveal that human monocyte-derived DC are able to use two migration modes in 3D. In porous matrices of fibrillar collagen I, iDC adopted the amoeboid migration mode. In dense matrices of gelled collagen I or Matrigel, iDC used the protease-dependent, ROCK-independent mesenchymal migration mode. Upon TLR4 activation by LPS, mDC-LPS lose the capacity to form podosomes and degrade the matrix along with impaired mesenchymal migration. TLR2 activation by Pam 3 CSK 4 resulted in DC maturation, podosome maintenance, and efficient mesenchymal migration. Under all these conditions, when DC used the mesenchymal mode in dense matrices, they formed 3D podosomes at the tip of cell protrusions. Using PGE 2 , known to disrupt podosomes in DC, we observed that the cells remained in an immature status and the mesenchymal migration mode was abolished. We also observed that, while CCL5 (attractant of iDC) enhanced both amoeboid and mesenchymal migration of iDC, CCL19 and CCL21 (attractants of mDC) only enhanced mDC-LPS amoeboid migration without triggering mesenchymal migration. Finally, we examined the migration of iDC in tumor cell spheroids, a tissue-like 3D environment. We observed that iDC infiltrated spheroids of tumor cells using both migration modes. Altogether, these results demonstrate that human DC adopt the mesenchymal mode to migrate in 3D dense environments, which relies on their capacity to form podosomes independent of their maturation status, paving the way of further investigations on in vivo DC migration in dense tissues and its regulation during infections.

Discovery of dense aggregations of stalked crinoids in Izu-Ogasawara trench, Japan.

PubMed

Oji, Tatsuo; Ogawa, Yujiro; Hunter, Aaron W; Kitazawa, Kota

2009-06-01

Stalked crinoids are recognized as living fossils that typically inhabit modern deep-water environments exceeding 100 m. Previous records of stalked crinoids from hadal depths (exceeding 6000 m) are extremely rare, and no in-situ information has been available. We show here that stalked crinoids live densely on rocky substrates at depths over 9000 m in the Izu-Ogasawara Trench off the eastern coast of Japan, evidenced by underwater photos and videos taken by a remotely operated vehicle. This is the deepest in-situ observation of stalked crinoids and demonstrates that crinoid meadows can exist at hadal depths close to the deepest ocean floor, in a fashion quite similar to populations observed in shallower depths.

The Identification of Proteoglycans and Glycosaminoglycans in Archaeological Human Bones and Teeth

PubMed Central

Coulson-Thomas, Yvette M.; Coulson-Thomas, Vivien J.; Norton, Andrew L.; Gesteira, Tarsis F.; Cavalheiro, Renan P.; Meneghetti, Maria Cecília Z.; Martins, João R.; Dixon, Ronald A.; Nader, Helena B.

2015-01-01

Bone tissue is mineralized dense connective tissue consisting mainly of a mineral component (hydroxyapatite) and an organic matrix comprised of collagens, non-collagenous proteins and proteoglycans (PGs). Extracellular matrix proteins and PGs bind tightly to hydroxyapatite which would protect these molecules from the destructive effects of temperature and chemical agents after death. DNA and proteins have been successfully extracted from archaeological skeletons from which valuable information has been obtained; however, to date neither PGs nor glycosaminoglycan (GAG) chains have been studied in archaeological skeletons. PGs and GAGs play a major role in bone morphogenesis, homeostasis and degenerative bone disease. The ability to isolate and characterize PG and GAG content from archaeological skeletons would unveil valuable paleontological information. We therefore optimized methods for the extraction of both PGs and GAGs from archaeological human skeletons. PGs and GAGs were successfully extracted from both archaeological human bones and teeth, and characterized by their electrophoretic mobility in agarose gel, degradation by specific enzymes and HPLC. The GAG populations isolated were chondroitin sulfate (CS) and hyaluronic acid (HA). In addition, a CSPG was detected. The localization of CS, HA, three small leucine rich PGs (biglycan, decorin and fibromodulin) and glypican was analyzed in archaeological human bone slices. Staining patterns were different for juvenile and adult bones, whilst adolescent bones had a similar staining pattern to adult bones. The finding that significant quantities of PGs and GAGs persist in archaeological bones and teeth opens novel venues for the field of Paleontology. PMID:26107959

Risk behaviors in a rural community with a known point-source exposure to chronic wasting disease

PubMed Central

Garruto, Ralph M; Reiber, Chris; Alfonso, Marta P; Gastrich, Heidi; Needham, Kelsey; Sunderman, Sarah; Walker, Sarah; Weeks, Jennifer; DeRosa, Nicholas; Faisst, Eric; Dunn, John; Fanelli, Kenneth; Shilkret, Kenneth

2008-01-01

Background The emergence and continuing spread of Chronic Wasting Disease (CWD) in cervids has now reached 14 U.S. states, two Canadian provinces, and South Korea, producing a potential for transmission of CWD prions to humans and other animals globally. In 2005, CWD spread for the first time from the Midwest to more densely populated regions of the East Coast. As a result, a large cohort of individuals attending a wild game feast in upstate New York were exposed to a deer that was subsequently confirmed positive for CWD. Methods Eighty-one participants who ingested or otherwise were exposed to a deer with chronic wasting disease at a local New York State sportsman's feast were recruited for this study. Participants were administered an exposure questionnaire and agreed to follow-up health evaluations longitudinally over the next six years. Results Our results indicate two types of risks for those who attended the feast, a Feast Risk and a General Risk. The larger the number of risk factors, the greater the risk to human health if CWD is transmissible to humans. Long-term surveillance of feast participants exposed to CWD is ongoing. Conclusion The risk data from this study provide a relative scale for cumulative exposure to CWD-infected tissues and surfaces, and those in the upper tiers of cumulative risk may be most at risk if CWD is transmissible to humans. PMID:18577220

Sickle cell anemia: a potential nutritional approach for a molecular disease.

PubMed

Ohnishi, S T; Ohnishi, T; Ogunmola, G B

2000-05-01

A certain population of red blood cells in patients with sickle cell anemia has an elevated density and possesses an abnormal membrane. These "dense cells" have a tendency to adhere to neutrophils, platelets, and vascular endothelial cells, and, thus, they could trigger vasoocclusion and the subsequent painful crisis from which these patients suffer. We developed a laboratory method of preparing such dense cells and found that nutritional antioxidant supplements, hydroxyl radical scavengers, and iron-binding agents could inhibit the formation of dense cells in vitro. The concentrations at which effective nutritional supplements could inhibit dense cell formation by 50% were 4.0 mg/mL for aged garlic extract, 0.38 mg/mL for black tea extract, 0.13 mg/mL for green tea extract, 0.07 mg/mL for Pycnogenol, 930 microM for alpha-lipoic acid, 270 microM for vitamin E, 45 microM for coenzyme Q(10), and 32 microM for beta-carotene. Both an ex vivo study and a pilot clinical trial demonstrated that a cocktail consisting of daily doses of 6 g of aged garlic extract, 4-6 g of vitamin C, and 800 to 1200 IU of vitamin E may indeed be beneficial to the patients.

Blending local scale information for developing agricultural resilience in Ethiopia

USGS Publications Warehouse

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

2013-01-01

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

Projecting avian responses to landscape managment along the middle RIO GRANDE, New Mexico

USDA-ARS?s Scientific Manuscript database

Lack of flooding due to river impoundments on the middle Rio Grande has contributed to the spread of exotic vegetation with dense understory fuel loads. Restoration has focused on understory vegetation thinning but it is unclear how these actions impact bird populations. We quantified densities of ...

The Genetic Basis for Evolved Tolerance to Dioxin-Like Compounds in Wild Atlantic Killifish: More Than the Aryl Hydrocarbon Receptor

EPA Science Inventory

Populations of Atlantic killifish (Fundulus heteroclitus) resident to some US urban estuaries have independently evolved extreme and inherited tolerance to toxic dioxin-like compounds (DLCs). To further understand the genetic basis for this trait, we densely genotyped families o...

ENHANCED ORGANIC MATTER REMINERALIZATION AND NUTRIENT TURNOVER BY BURROWING SHRIMP POPULATIONS IN YAQUINA BAY, OR

EPA Science Inventory

Burrowing thalassinid shrimp are major ecological components of Pacific Northwest (PNW) estuaries and where they structure large areas of intertidal and shallow subtidal habitat. These crustaceans occur in dense beds (>250 m-2) and dig extensive burrow systems (>1 m) controlling ...

Aspirations for a Master's-Level Teaching Profession in England

ERIC Educational Resources Information Center

Thomas, Lorraine

2016-01-01

This research investigates aspirations for a master's-level teaching profession in England, providing key stakeholder perceptions in one densely populated region within a multiple case study. Although this intended move to a master's-level profession represented a major shift in teachers' professional development in England, only limited…

A Theory of the Origin of the State

ERIC Educational Resources Information Center

Carneiro, Robert L.

1970-01-01

Suggests that states evolve in response to ecological or social circumscription, or resource concentration. When dense populations develop, fighting over land forces loser into political subordination or incorporation. This modification of coercive theories explain lack of state in Amazon basin and origin of Inca, Maya, Hwang Valley states.…

Child overweight in rural America: the role of parent feeding styles

USDA-ARS?s Scientific Manuscript database

Evidence from studies conducted in urban and suburban areas suggest that caregivers, through their parenting styles, influence a child’s weight. In rural areas, where the prevalence of obesity is 25% higher than in more densely populated regions, the role of the caregiver has not been adequately stu...

Wildland Fire: Health Effects and Public Health Outreach: Southeast Regional Partnership for Planning and Sustainability (SERPPAS) Webinar

EPA Science Inventory

The expanding wildland-urban interface and the proximity of prescribed fires undertaken by the Department of Defense is bringing the source of wildland fires close to densely populated areas in the Southeast. The presentation is an informational webinar to representatives of SERP...

Climate change in Asia and the Pacific: How can countries adapt?

USDA-ARS?s Scientific Manuscript database

The Asia Pacific (AP) region is more vulnerable to climate change risks than other regions, given its dependence on the natural resources and agricultural sector for economic development with densely populated coastal areas, weak institutions, and the poverty of a considerable proportion of its popu...

Exploring synergies between transit investment and dense redevelopment: A scenario analysis in a rapidly urbanizing landscape

EPA Science Inventory

Like many urban areas around the world, Durham and Orange counties in North Carolina, USA are experiencing population growth and sprawl that is putting stress on the transportation system. Light rail and denser transit-oriented development are being considered as possible solutio...

Impact of surface water withdrawals on water storage variations under a changing climate

NASA Astrophysics Data System (ADS)

Ashraf, B.; AghaKouchak, A.; Mousavi Baygi, M.; Alizadeh, A.; Moftakhari, H.; Miao, C.; Arab, D. R.; Anjileli, H.

2016-12-01

Quantitative evaluation of water storage variations in large river basins is an important element of water management, especially in a climate change. In addition, human water use has developed into another strong driver of water storage changes especially in densely populated semiarid and arid areas. In this study, we estimate the normalized human outflow of the thirty main basins in Iran during the past three decades. Then, we investigate the individual and combined effects of climate variability and human water withdrawals on surface water storage in the 21st century in four major basins (Urmia, Karkheh, Karun and Jarrahi) located in semi-arid areas of Iran. These basins are selected because they experienced medium to high human-induced water demand in last decades. We use bias-corrected historical simulations and future projections from 26 General Circulation Models (GCMs) and three climate change scenarios RCP2.6, RCP4.5, RCP8.5). The results show that humans have strongly impacted the water balances of most basins in Iran, dominating potential climate change impacts in the historical period. In fact, the main reason for water scarcity in these regions appears to be due to the increased anthropogenic water demand resulting from substantial socio-economic growth in the past three decades. Furthermore, by the end of the 21st century, the compounding effects of increased irrigation water demand and precipitation variability may lead to severe local water scarcity in these basins. Our study highlights the need to improve our understanding of the hydrologic responses to anthropogenic perturbations, and local water resource management decisions.

Establishment and characterization of a new human functional cell line from a choriocarcinoma.

PubMed

Okabe, T; Sasaki, N; Matsuzaki, M; Imai, Y; Kaneko, Y; Matsuzaki, F; Takaku, F; Tsushima, T

1983-10-01

A new human functional tumor cell line, designated as T3M-3, has been established from a xenotransplanted choriocarcinoma grown in nude mice. One of the biggest problems of the in vitro culture of these tumor cells using the xenotransplanted tumors had been the dense contamination of fibroblasts of host nude mouse origin. In the present study, these fibroblasts were completely removed by incubating the cells with antiserum raised against nude mouse spleen cells. The cell line established from the remaining tumor cells has been successfully propagated in vitro for as long as 4 years. These cells show the morphology of epithelioid cells containing a prominent nucleus with one or two large nucleoli. The cells grow in a monolayered sheet with the population-doubling time of 19 hr. The cells show perfect tumor takes when they are reinoculated into nude mice. Chromosomal analysis revealed that the cell is a human aneuploid one with a hypotriploid mode. These cultured cells maintained well the function of secreting large amounts of human chorionic gonadotropin, progesterone, and estrogen. The secretion of human chorionic gonadotropin and progesterone by these cells is enhanced by stimulation with tumor promoters, such as 12-O-tetradecanoylphorbol-13-acetate and teleocidin B, or with epidermal growth factor in a dose-and time-dependent manner. Interestingly, however, the tumor promoters did not exert a marked effect on the cellular binding of epidermal growth factor, indicating that the receptors for these reagents in T3M-3 cells are not shared by epidermal growth factor.

Predictions of adult Anopheles albimanus densities in villages based on distances to remotely sensed larval habitats

NASA Technical Reports Server (NTRS)

Rejmankova, E.; Roberts, D. R.; Pawley, A.; Manguin, S.; Polanco, J.

1995-01-01

Remote sensing is particularly helpful for assessing the location and extent of vegetation formations, such as herbaceous wetlands, that are difficult to examine on the ground. Marshes that are sparsely populated with emergent macrophytes and dense cyanobacterial mats have previously been identified as very productive Anopheles albimanus larval habitats. This type of habitat was detectable on a classified multispectral System Probatoire d'Observation de la Terre image of northern Belize as a mixture of two isoclasses. A similar spectral signature is characteristic for vegetation of river margins consisting of aquatic grasses and water hyacinth, which constitutes another productive larval habitat. Based on the distance between human settlements (sites) of various sizes and the nearest marsh/river exhibiting this particular class combination, we selected two groups of sites: those located closer than 500 m and those located more than 1,500 m from such habitats. Based on previous adult collections near larval habitats, we defined a landing rate of 0.5 mosquitoes/human/min from 6:30 PM to 8:00 PM as the threshold for high (> or = 0.5 mosquitoes/human/min) versus low (< 0.5 mosquitoes/human/min) densities of An. albimanus. Sites located less than 500 m from the habitat were predicted as having values higher than this threshold, while lower values were predicted for sites located greater than 1,500 m from the habitat. Predictions were verified by collections of mosquitoes landing on humans. The predictions were 100% accurate for sites in the > 1,500-m category and 89% accurate for sites in the < 500-m category.

Diadema ascensionis (Echinodermata: Echinoidea) is not restricted to Oceanic Islands: evidence from morphological data.

PubMed

Gondim, A I; Dias, T L P; Christoffersen, M L

2013-05-01

The genus Diadema presently consists of seven species, two of which are known from the Brazilian coast: D. antillarum and D. ascensionis. The first is usually known for shallow coastal areas, while the second was apparently restricted to oceanic islands. In February 2011, a dense population of D. ascensionis was observed on the coastal reefs of Praia do Francês (Alagoas State, northeastern Brazil). Five specimens were collected and transported to the laboratory where morphological studies of the test and pedicellariae were conducted. Subsequently, visits were made to scientific collections in order to compare and confirm species identifications. Our observations confirm the presence of tridentate pedicellariae with narrow and strongly curved valves. The axial cavity in the tips of the spines is filled with dense nonreticular tissue. This taxonomic data confirms the occurrence of D. ascensionis in coastal areas. On the coastal reefs of Praia do Francês, animals were observed from the beach to the reef formations about 200 m offshore in areas with a sandy substrate and in reef cavities, usually in clear and well illuminated waters. Solitary individuals or groups of up to 15 individuals formed dense populations in the area. We stress the importance of pedicellariae for the specific identification of the Diadematidae, considering that they are quite constant and reliable at this taxonomic level. Our results demonstrate that D. ascensionis is not restricted to insular environments and that this species may be common in shallow coastal habitats.

Relationships between population and environment in rural areas of developing countries.

PubMed

Rudel, T I

1991-01-01

Studies that have assessed the impact of population change on the environment in rural areas of selected developing countries are reviewed. The implications are that both developed and developing countries might focus on single aspects of a much larger global problem. Rural areas were selected because the bulk of the world's population lives in rural areas. Population environment interactions are 1st discussed at the global level. Studies on changing import patterns of developing countries are usless in accounting for agricultural policy shifts or other factors that may be unrelated to population growth but may be related to food imports. When the magnitude of food production and population growth is examined, there is a balance established between the two. However, analysis of the spatial distribution of desertification and soil degradation shows greater local level effects. Population/environment relationships are examined in critical ecological zones: tropical deforestation, desertification, land degradation in resource poor zones, and responses to population pressures and resource degradation. The conclusions reached are that better statistics on degradation are needed and that the trends in the human ecology of rural populations have clear implications for government policies on the environment. Agricultural development has been uneven and inequitable such that many peasant populations have suffered a decline in standards of living, particularly in Africa. There has also been an accelerated increase in rates of land degradation in resource poor areas, which are densely populated. The population response has been migration shifts out of resource poor areas to ecologically marginal areas, which has resulted in extensive desertification and deforestation. Expansion of the areas under cultivation has not just increased agricultural production but agriculture and population have invaded ecologically marginal zones in deserts and rain forests. Measurement of the magnitude and geographic distribution of deforestation is enhanced with the use of remote sensing techniques, such as those used in the 1982 UN Food and Agriculture baseline study. Soil degradation is not so easily measured. The implications are that regional development funds need to directed away from critical zones or areas adjacent to critical zones. Research is needed to understand rural to rural migration.

Binaries, cluster dynamics and population studies of stars and stellar phenomena

NASA Astrophysics Data System (ADS)

Vanbeveren, Dany

2005-10-01

The effects of binaries on population studies of stars and stellar phenomena have been investigated over the past 3 decades by many research groups. Here we will focus mainly on the work that has been done recently in Brussels and we will consider the following topics: the effect of binaries on overall galactic chemical evolutionary models and on the rates of different types of supernova, the population of point-like X-ray sources where we distinguish the standard high mass X-ray binaries and the ULXs, a UFO-scenario for the formation of WR+OB binaries in dense star systems. Finally we critically discuss the possible effect of rotation on population studies.

Amelogenin-assisted ex vivo remineralization of human enamel: effects of supersaturation degree and fluoride concentration

PubMed Central

Fan, Yuwei; Nelson, James R.; Alvarez, Jason R.; Hagan, Joseph; Berrier, Allison; Xu, Xiaoming

2011-01-01

The formation of organized nanocrystals that resemble enamel is crucial for successful enamel remineralization. Calcium, phosphate and fluoride ions and amelogenin are important ingredients for the formation of organized hydroxyapatite (HAP) crystals in vitro. However, the effects of these remineralization agents on the enamel crystal morphology have not been thoroughly studied. The objective of this study was to investigate the effects of fluoride ions, supersaturation degree and amelogenin on the crystal morphology and organization of ex vivo remineralized human enamel. Extracted third molars were sliced thin and acid-etched to provide the enamel surface for immersion in different remineralization solutions. The crystal morphology and mineral phase of the remineralized enamel surface were analyzed by FE-SEM, ATR-FTIR and XRD. The concentration of fluoride and supersaturation degree of hydroxyapatite had significant effects on the crystal morphology and crystal organization, which varied from plate-like loose crystals to rod-like densely packed nanocrystal arrays. Densely packed arrays of fluoridated hydroxyapatite nanorods were observed under the following conditions: σ(HAP) = 10.2±2.0 with fluoride 1.5±0.5 mg/L and amelogenin 40±10 µg/mL, pH 6.8±0.4. A phase diagram summarized the conditions that form dense or loose hydroxyapatite nanocrystal structures. This study provides the basis for the development of novel dental materials for caries management. PMID:21256987

Prevalence of Mycobacterium tuberculosis antibodies in a healthy population in a South-Eastern State of Nigeria.

PubMed

Chinedu, Awujo N; Seema, Bibi; Gladys, Anyanwu O

2008-01-01

To determine the seroprevalence of Mycobacterium tuberculosis in apparently healthy residents of two densely-populated and model settlement nucleated towns of Akwakuma and Orji in Owerri North Local Government Area of Imo State, South Eastern Nigeria. Antibodies to M. tuberculosis in human serum or plasma were qualitatively detected in four hundred and eighty individuals using the one step TB 1gG/1gM two sided-lateral flow chromatographic immunoassay. The prevalence of M. tuberculosis antibodies in the study population was 6.67%. However, the prevalence was significantly higher (p<0.05) in sera of inhabitants of Orji (8.33%) than in those of Akwakuma (5.56%). Generally, in both communities, the females were significantly (p<0.05) more sero-positive for M. tuberculosis antibodies (8.57%) than the males (4.0%). The antibodies were most prevalent (22.2%) in persons between the ages of 20 and 29 years. No M. tuberculosis antibody was detected in individuals that were in the 1-9, 30-39 and 50-59 year age groups. Amongst the study population, the bacterial antibodies were only detected in 25.0% of the males in Orji that were between 20 and 29 years. Comparatively, the antibodies were prevalent (16.7%) in female residents of Akwakuma that were within the 10-19 and 40-49 years age group. The high prevalence of M. tuberculosis in the study population is worrisome as the sero-positive individuals are not only at risk of having full blown tuberculosis later on, but are also a source of spreading the bacteria to the populace. Therefore, there is an urgent need for further epidemiological survey to be undertaken in the study area and, to initiate appropriate preventive and control measures.

Effect through inhalation on human health of PM1 bound polycyclic aromatic hydrocarbons collected from foggy days in northern part of India.

PubMed

Singh, Dharmendra Kumar; Gupta, Tarun

2016-04-05

We investigated the health risk from 16 polycyclic aromatic hydrocarbons (PAHs) adsorbed on submicron particles and also reported their concentrations, spatial distribution and possible sources during foggy days at Kanpur. Twenty-four urban foggy day's samples gathered from Kanpur, an urban center in North India and most densely populated city in the Indo-Gangetic plain of India, were examined for 16 PAHs (2-6 rings).The mean concentration of PM1 was found to be 160.16±37.70μg/m(3). ∑16PAHs concentrations were 529.17ng/m(3) with a mean of 33.07ng/m(3). The compounds of higher molecular weight (4-6 rings) added to 70.67% of ∑PAHs mass concentration in the foggy day's samples. The results of source identification by using principle component analysis (PCA) and diagnostic ratios proposed that the primary sources of PAHs were vehicular emission (primarily driven by diesel fuel) and coal combustion and the secondary source. Exposure to total PAHs in the ambient air resulted in, 95% probability total Incremental Lifetime Cancer Risk (TILCR) 3.57×10(-5) for adults and 2.08×10(-5) for children or (∼35 cancer case per million in adults and ∼20 cancer case per million in children) due to inhalation in terms of ILCR were higher than the baseline value of acceptable risk (one cancer case per million people) suggesting moderate health risk to resident human population. Copyright © 2015 Elsevier B.V. All rights reserved.

Spatial and Temporal Dynamics of Cyanobacterial Blooms in Two Rhode Island Ponds.

EPA Science Inventory

Cyanobacteria are natural components of freshwater ecosystems. When conditions are favorable (e.g., high nutrient inputs), cyanobacteria can form dense blooms that have negative effects on human and animal health, ecosystem functioning, and aesthetics. When blooms occur they can ...

Spatial and Temporal Dynamics of Cyanobacterial Blooms in Two Rhode Island Ponds

EPA Science Inventory

Cyanobacteria are natural components of freshwater ecosystems. When conditions are favorable (e.g., high nutrient inputs), cyanobacteria can form dense blooms that have negative effects on human and animal health, ecosystem functioning, and aesthetics. When blooms occur they ca...

Impact of different study populations on reader behavior and performance metrics: initial results

NASA Astrophysics Data System (ADS)

Gallas, Brandon D.; Pisano, Etta; Cole, Elodia; Myers, Kyle

2017-03-01

The FDA recently completed a study on design methodologies surrounding the Validation of Imaging Premarket Evaluation and Regulation called VIPER. VIPER consisted of five large reader sub-studies to compare the impact of different study populations on reader behavior as seen by sensitivity, specificity, and AUC, the area under the ROC curve (receiver operating characteristic curve). The study investigated different prevalence levels and two kinds of sampling of non-cancer patients: a screening population and a challenge population. The VIPER study compared full-field digital mammography (FFDM) to screenfilm mammography (SFM) for women with heterogeneously dense or extremely dense breasts. All cases and corresponding images were sampled from Digital Mammographic Imaging Screening Trial (DMIST) archives. There were 20 readers (American Board Certified radiologists) for each sub-study, and instead of every reader reading every case (fully-crossed study), readers and cases were split into groups to reduce reader workload and the total number of observations (split-plot study). For data collection, readers first decided whether or not they would recall a patient. Following that decision, they provided an ROC score for how close or far that patient was from the recall decision threshold. Performance results for FFDM show that as prevalence increases to 50%, there is a moderate increase in sensitivity and decrease in specificity, whereas AUC is mainly flat. Regarding precision, the statistical efficiency (ratio of variances) of sensitivity and specificity relative to AUC are 0.66 at best and decrease with prevalence. Analyses comparing modalities and the study populations (screening vs. challenge) are still ongoing.

Impact of Different Study Populations on Reader Behavior and Performance Metrics: Initial Results

PubMed Central

Gallas, Brandon D.; Pisano, Etta; Cole, Elodia; Myers, Kyle

2017-01-01

The FDA recently completed a study on design methodologies surrounding the Validation of Imaging Premarket Evaluation and Regulation called VIPER. VIPER consisted of five large reader sub-studies to compare the impact of different study populations on reader behavior as seen by sensitivity, specificity, and AUC, the area under the ROC curve (receiver operating characteristic curve). The study investigated different prevalence levels and two kinds of sampling of non-cancer patients: a screening population and a challenge population. The VIPER study compared full-field digital mammography (FFDM) to screen-film mammography (SFM) for women with heterogeneously dense or extremely dense breasts. All cases and corresponding images were sampled from Digital Mammographic Imaging Screening Trial (DMIST) archives. There were 20 readers (American Board Certified radiologists) for each sub-study, and instead of every reader reading every case (fully-crossed study), readers and cases were split into groups to reduce reader workload and the total number of observations (split-plot study). For data collection, readers first decided whether or not they would recall a patient. Following that decision, they provided an ROC score for how close or far that patient was from the recall decision threshold. Performance results for FFDM show that as prevalence increases to 50%, there is a moderate increase in sensitivity and decrease in specificity, whereas AUC is mainly flat. Regarding precision, the statistical efficiency (ratio of variances) of sensitivity and specificity relative to AUC are 0.66 at best and decrease with prevalence. Analyses comparing modalities and the study populations (screening vs. challenge) are still ongoing. PMID:28845078

Quantitative Comparison of Dense-Core Amyloid Plaque Accumulation in Amyloid-β Protein Precursor Transgenic Mice.

PubMed

Liu, Peng; Reichl, John H; Rao, Eshaan R; McNellis, Brittany M; Huang, Eric S; Hemmy, Laura S; Forster, Colleen L; Kuskowski, Michael A; Borchelt, David R; Vassar, Robert; Ashe, Karen H; Zahs, Kathleen R

2017-01-01

There exist several dozen lines of transgenic mice that express human amyloid-β protein precursor (AβPP) with Alzheimer's disease (AD)-linked mutations. AβPP transgenic mouse lines differ in the types and amounts of Aβ that they generate and in their spatiotemporal patterns of expression of Aβ assemblies, providing a toolkit to study Aβ amyloidosis and the influence of Aβ aggregation on brain function. More complete quantitative descriptions of the types of Aβ assemblies present in transgenic mice and in humans during disease progression should add to our understanding of how Aβ toxicity in mice relates to the pathogenesis of AD. Here, we provide a direct quantitative comparison of amyloid plaque burdens and plaque sizes in four lines of AβPP transgenic mice. We measured the fraction of cortex and hippocampus occupied by dense-core plaques, visualized by staining with Thioflavin S, in mice from young adulthood through advanced age. We found that the plaque burdens among the transgenic lines varied by an order of magnitude: at 15 months of age, the oldest age studied, the median cortical plaque burden in 5XFAD mice was already ∼4.5 times that of 21-month-old Tg2576 mice and ∼15 times that of 21-24-month-old rTg9191 mice. Plaque-size distributions changed across the lifespan in a line- and region-dependent manner. We also compared the dense-core plaque burdens in the mice to those measured in a set of pathologically-confirmed AD cases from the Nun Study. Cortical plaque burdens in Tg2576, APPSwePS1ΔE9, and 5XFAD mice eventually far exceeded those measured in the human cohort.

Quantitative Comparison of Dense-Core Amyloid Plaque Accumulation in Amyloid-β Precursor Protein Transgenic Mice

PubMed Central

Liu, Peng; Reichl, John H.; Rao, Eshaan R.; McNellis, Brittany M.; Huang, Eric S.; Hemmy, Laura S.; Forster, Colleen L.; Kuskowski, Michael A.; Borchelt, David R.; Vassar, Robert; Ashe, Karen H.; Zahs, Kathleen R.

2016-01-01

There exist several dozen lines of transgenic mice that express human amyloid-β precursor protein (AβPP) with Alzheimer’s disease (AD)-linked mutations. AβPP transgenic mouse lines differ in the types and amounts of Aβ that they generate and in their spatiotemporal patterns of expression of Aβ assemblies, providing a toolkit to study Aβ amyloidosis and the influence of Aβ aggregation on brain function. More complete quantitative descriptions of the types of Aβ assemblies present in transgenic mice and in humans during disease progression should add to our understanding of how Aβ toxicity in mice relates to the pathogenesis of AD. Here, we provide a direct quantitative comparison of amyloid plaque burdens and plaque sizes in four lines of AβPP transgenic mice. We measured the fraction of cortex and hippocampus occupied by dense-core plaques, visualized by staining with Thioflavin S, in mice from young adulthood through advanced age. We found that the plaque burdens among the transgenic lines varied by an order of magnitude: at 15 months of age, the oldest age studied, the median cortical plaque burden in 5XFAD mice was already ~4.5 times that of 21-month Tg2576 mice and ~15 times that of 21–24-month rTg9191 mice. Plaque-size distributions changed across the lifespan in a line- and region-dependent manner. We also compared the dense-core plaque burdens in the mice to those measured in a set of pathologically-confirmed AD cases from the Nun Study. Cortical plaque burdens in Tg2576, APPSwePS1ΔE9, and 5XFAD mice eventually far exceeded those measured in the human cohort. PMID:28059792

Robust assessment of the expansion and retreat of Mediterranean climate in the 21st century

PubMed Central

Alessandri, Andrea; De Felice, Matteo; Zeng, Ning; Mariotti, Annarita; Pan, Yutong; Cherchi, Annalisa; Lee, June-Yi; Wang, Bin; Ha, Kyung-Ja; Ruti, Paolo; Artale, Vincenzo

2014-01-01

The warm-temperate regions of the globe characterized by dry summers and wet winters (Mediterranean climate; MED) are especially vulnerable to climate change. The potential impact on water resources, ecosystems and human livelihood requires a detailed picture of the future changes in this unique climate zone. Here we apply a probabilistic approach to quantitatively address how and why the geographic distribution of MED will change based on the latest-available climate projections for the 21st century. Our analysis provides, for the first time, a robust assessment of significant northward and eastward future expansions of MED over both the Euro-Mediterranean and western North America. Concurrently, we show a significant 21st century replacement of the equatorward MED margins by the arid climate type. Moreover, future winters will become wetter and summers drier in both the old and newly established MED zones. Should these projections be realized, living conditions in some of the most densely populated regions in the world will be seriously jeopardized. PMID:25448867

Identifying Ancient Settlement Patterns through LiDAR in the Mosquitia Region of Honduras.

PubMed

Fisher, Christopher T; Fernández-Diaz, Juan Carlos; Cohen, Anna S; Neil Cruz, Oscar; Gonzáles, Alicia M; Leisz, Stephen J; Pezzutti, Florencia; Shrestha, Ramesh; Carter, William

2016-01-01

The Mosquitia ecosystem of Honduras occupies the fulcrum between the American continents and as such constitutes a critical region for understanding past patterns of socio-political development and interaction. Heavy vegetation, rugged topography, and remoteness have limited scientific investigation. This paper presents prehistoric patterns of settlement and landuse for a critical valley within the Mosquitia derived from airborne LiDAR scanning and field investigation. We show that (i) though today the valley is a wilderness it was densely inhabited in the past; (ii) that this population was organized into a three-tiered system composed of 19 settlements dominated by a city; and, (iii) that this occupation was embedded within a human engineered landscape. We also add to a growing body of literature that demonstrates the utility of LiDAR as means for rapid cultural assessments in undocumented regions for analysis and conservation. Our ultimate hope is for our work to promote protections to safeguard the unique and critically endangered Mosquitia ecosystem and other similar areas in need of preservation.

The Airborne Metagenome in an Indoor Urban Environment

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

Tringe, Susannah; Zhang, Tao; Liu, Xuguo

2008-02-12

The indoor atmosphere is an ecological unit that impacts on public health. To investigate the composition of organisms in this space, we applied culture-independent approaches to microbes harvested from the air of two densely populated urban buildings, from which we analyzed 80 megabases genomic DNA sequence and 6000 16S rDNA clones. The air microbiota is primarily bacteria, including potential opportunistic pathogens commonly isolated from human-inhabited environments such as hospitals, but none of the data contain matches to virulent pathogens or bioterror agents. Comparison of air samples with each other and nearby environments suggested that the indoor air microbes are notmore » random transients from surrounding outdoor environments, but rather originate from indoor niches. Sequence annotation by gene function revealed specific adaptive capabilities enriched in the air environment, including genes potentially involved in resistance to desiccation and oxidative damage. This baseline index of air microbiota will be valuable for improving designs of surveillance for natural or man-made release of virulent pathogens.« less

Crosstalk in concurrent repeated games impedes direct reciprocity and requires stronger levels of forgiveness.

PubMed

Reiter, Johannes G; Hilbe, Christian; Rand, David G; Chatterjee, Krishnendu; Nowak, Martin A

2018-02-07

Direct reciprocity is a mechanism for cooperation among humans. Many of our daily interactions are repeated. We interact repeatedly with our family, friends, colleagues, members of the local and even global community. In the theory of repeated games, it is a tacit assumption that the various games that a person plays simultaneously have no effect on each other. Here we introduce a general framework that allows us to analyze "crosstalk" between a player's concurrent games. In the presence of crosstalk, the action a person experiences in one game can alter the person's decision in another. We find that crosstalk impedes the maintenance of cooperation and requires stronger levels of forgiveness. The magnitude of the effect depends on the population structure. In more densely connected social groups, crosstalk has a stronger effect. A harsh retaliator, such as Tit-for-Tat, is unable to counteract crosstalk. The crosstalk framework provides a unified interpretation of direct and upstream reciprocity in the context of repeated games.

Meningeal mast cells affect early T cell central nervous system infiltration and blood-brain barrier integrity through TNF: a role for neutrophil recruitment?

PubMed

Sayed, Blayne A; Christy, Alison L; Walker, Margaret E; Brown, Melissa A

2010-06-15

Mast cells contribute to the pathogenesis of experimental autoimmune encephalomyelitis, a rodent model of the human demyelinating disease multiple sclerosis. Yet their site and mode of action is unknown. In both diseases, myelin-specific T cells are initially activated in peripheral lymphoid organs. However, for disease to occur, these cells must enter the immunologically privileged CNS through a breach in the relatively impermeable blood-brain barrier. In this study, we demonstrate that a dense population of resident mast cells in the meninges, structures surrounding the brain and spinal cord, regulate basal CNS barrier function, facilitating initial T cell CNS entry. Through the expression of TNF, mast cells recruit an early wave of neutrophils to the CNS. We propose that neutrophils in turn promote the blood-brain barrier breach and together with T cells lead to further inflammatory cell influx and myelin damage. These findings provide specific targets for intervention in multiple sclerosis as well as other immune-mediated CNS diseases.

Historical trends of atmospheric black carbon on Sanjiang Plain as reconstructed from a 150-year peat record

PubMed Central

Gao, Chuanyu; Lin, Qianxin; Zhang, Shaoqing; He, Jiabao; Lu, Xianguo; Wang, Guoping

2014-01-01

Black carbon (BC), one of the major components of atmosphere aerosol, could be the second dominant driver of climate change. We reconstructed historical trend of BC fluxes in Sanjiang Plain (Northeast China) through peat record to better understand its long-term trend and relationship of this atmosphere aerosol with intensity of human activities. The BC fluxes in peatland were higher than other sedimentary archives. Although global biomass burning decreased in last 150 years, regional large scale reclaiming caused BC fluxes of the Sanjiang Plain increased dramatically between 1950s' and 1980s', most likely resulting from using fire to clearing dense pastures and forests for reclaiming. The BC fluxes have increased since 1900s with increasing of the population and the area of farmland; the increase trend has been more clearly since 1980s. Based on Generalized additive models (GAM), the proportional influence of regional anthropogenic impacts have increased and became dominant factors on BC deposition. PMID:25029963

A window-based time series feature extraction method.

PubMed

Katircioglu-Öztürk, Deniz; Güvenir, H Altay; Ravens, Ursula; Baykal, Nazife

2017-10-01

This study proposes a robust similarity score-based time series feature extraction method that is termed as Window-based Time series Feature ExtraCtion (WTC). Specifically, WTC generates domain-interpretable results and involves significantly low computational complexity thereby rendering itself useful for densely sampled and populated time series datasets. In this study, WTC is applied to a proprietary action potential (AP) time series dataset on human cardiomyocytes and three precordial leads from a publicly available electrocardiogram (ECG) dataset. This is followed by comparing WTC in terms of predictive accuracy and computational complexity with shapelet transform and fast shapelet transform (which constitutes an accelerated variant of the shapelet transform). The results indicate that WTC achieves a slightly higher classification performance with significantly lower execution time when compared to its shapelet-based alternatives. With respect to its interpretable features, WTC has a potential to enable medical experts to explore definitive common trends in novel datasets. Copyright © 2017 Elsevier Ltd. All rights reserved.

Sources and sinks of plastic debris in estuaries: A conceptual model integrating biological, physical and chemical distribution mechanisms.

PubMed

Vermeiren, Peter; Muñoz, Cynthia C; Ikejima, Kou

2016-12-15

Micro- and macroplastic accumulation threatens estuaries worldwide because of the often dense human populations, diverse plastic inputs and high potential for plastic degradation and storage in these ecosystems. Nonetheless, our understanding of plastic sources and sinks remains limited. We designed conceptual models of the local and estuary-wide transport of plastics. We identify processes affecting the position of plastics in the water column; processes related to the mixing of fresh and salt water; and processes resulting from the influences of wind, topography, and organism-plastic interactions. The models identify gaps in the spatial context of plastic-organisms interactions, the chemical behavior of plastics in estuaries, effects of wind on plastic suspension-deposition cycles, and the relative importance of processes affecting the position in the water column. When interpreted in the context of current understanding, sinks with high management potential can be identified. However, source-sink patterns vary among estuary types and with local scale processes. Copyright © 2016 Elsevier Ltd. All rights reserved.

Computer vision uncovers predictors of physical urban change.

PubMed

Naik, Nikhil; Kominers, Scott Duke; Raskar, Ramesh; Glaeser, Edward L; Hidalgo, César A

2017-07-18

Which neighborhoods experience physical improvements? In this paper, we introduce a computer vision method to measure changes in the physical appearances of neighborhoods from time-series street-level imagery. We connect changes in the physical appearance of five US cities with economic and demographic data and find three factors that predict neighborhood improvement. First, neighborhoods that are densely populated by college-educated adults are more likely to experience physical improvements-an observation that is compatible with the economic literature linking human capital and local success. Second, neighborhoods with better initial appearances experience, on average, larger positive improvements-an observation that is consistent with "tipping" theories of urban change. Third, neighborhood improvement correlates positively with physical proximity to the central business district and to other physically attractive neighborhoods-an observation that is consistent with the "invasion" theories of urban sociology. Together, our results provide support for three classical theories of urban change and illustrate the value of using computer vision methods and street-level imagery to understand the physical dynamics of cities.

Computer vision uncovers predictors of physical urban change

PubMed Central

Naik, Nikhil; Kominers, Scott Duke; Raskar, Ramesh; Glaeser, Edward L.; Hidalgo, César A.

2017-01-01

Which neighborhoods experience physical improvements? In this paper, we introduce a computer vision method to measure changes in the physical appearances of neighborhoods from time-series street-level imagery. We connect changes in the physical appearance of five US cities with economic and demographic data and find three factors that predict neighborhood improvement. First, neighborhoods that are densely populated by college-educated adults are more likely to experience physical improvements—an observation that is compatible with the economic literature linking human capital and local success. Second, neighborhoods with better initial appearances experience, on average, larger positive improvements—an observation that is consistent with “tipping” theories of urban change. Third, neighborhood improvement correlates positively with physical proximity to the central business district and to other physically attractive neighborhoods—an observation that is consistent with the “invasion” theories of urban sociology. Together, our results provide support for three classical theories of urban change and illustrate the value of using computer vision methods and street-level imagery to understand the physical dynamics of cities. PMID:28684401

The Airborne Metagenome in an Indoor Urban Environment

PubMed Central

Liu, Xuguo; Yu, Yiting; Lee, Wah Heng; Yap, Jennifer; Yao, Fei; Suan, Sim Tiow; Ing, Seah Keng; Haynes, Matthew; Rohwer, Forest; Wei, Chia Lin; Tan, Patrick; Bristow, James; Rubin, Edward M.; Ruan, Yijun

2008-01-01

The indoor atmosphere is an ecological unit that impacts on public health. To investigate the composition of organisms in this space, we applied culture-independent approaches to microbes harvested from the air of two densely populated urban buildings, from which we analyzed 80 megabases genomic DNA sequence and 6000 16S rDNA clones. The air microbiota is primarily bacteria, including potential opportunistic pathogens commonly isolated from human-inhabited environments such as hospitals, but none of the data contain matches to virulent pathogens or bioterror agents. Comparison of air samples with each other and nearby environments suggested that the indoor air microbes are not random transients from surrounding outdoor environments, but rather originate from indoor niches. Sequence annotation by gene function revealed specific adaptive capabilities enriched in the air environment, including genes potentially involved in resistance to desiccation and oxidative damage. This baseline index of air microbiota will be valuable for improving designs of surveillance for natural or man-made release of virulent pathogens. PMID:18382653

Highly Diverse Morbillivirus-Related Paramyxoviruses in Wild Fauna of the Southwestern Indian Ocean Islands: Evidence of Exchange between Introduced and Endemic Small Mammals

PubMed Central

Mélade, Julien; Dietrich, Muriel; Ramasindrazana, Beza; Soarimalala, Voahangy; Lagadec, Erwan; le Minter, Gildas; Tortosa, Pablo; Heraud, Jean-Michel; de Lamballerie, Xavier; Goodman, Steven M.; Dellagi, Koussay

2014-01-01

ABSTRACT The Paramyxoviridae form an increasingly diverse viral family, infecting a wide variety of different hosts. In recent years, they have been linked to disease emergence in many different animal populations and in humans. Bats and rodents have been identified as major animal populations capable of harboring paramyxoviruses, and host shifting between these animals is likely to be an important driving factor in the underlying evolutionary processes that eventually lead to disease emergence. Here, we have studied paramyxovirus circulation within populations of endemic and introduced wild small mammals of the southwestern Indian Ocean region and belonging to four taxonomic orders: Rodentia, Afrosoricida, Soricomorpha, and Chiroptera. We report elevated infection levels as well as widespread paramyxovirus dispersal and frequent host exchange of a newly emerging genus of the Paramyxoviridae, currently referred to as the unclassified morbillivirus-related viruses (UMRVs). In contrast to other genera of the Paramyxoviridae, where bats have been shown to be a key host species, we show that rodents (and, in particular, Rattus rattus) are significant spreaders of UMRVs. We predict that the ecological particularities of the southwestern Indian Ocean, where small mammal species often live in densely packed, multispecies communities, in combination with the increasing invasion of R. rattus and perturbations of endemic animal communities by active anthropological development, will have a major influence on the dynamics of UMRV infection. IMPORTANCE Identification of the infectious agents that circulate within wild animal reservoirs is essential for several reasons: (i) infectious disease outbreaks often originate from wild fauna; (ii) anthropological expansion increases the risk of contact between human and animal populations and, as a result, the risk of disease emergence; (iii) evaluation of pathogen reservoirs helps in elaborating preventive measures to limit the risk of disease emergence. Many paramyxoviruses for which bats and rodents serve as major reservoirs have demonstrated their potential to cause disease in humans and animals. In the context of the biodiversity hot spot of southwestern Indian Ocean islands and their rich endemic fauna, we show that highly diverse UMRVs exchange between various endemic animal species, and their dissemination likely is facilitated by the introduced Rattus rattus. Hence, many members of the Paramyxoviridae appear well adapted for the study of the viral phylodynamics that may be associated with disease emergence. PMID:24829336

Immunogenicity is preferentially induced in sparse dendritic cell cultures

PubMed Central

Nasi, Aikaterini; Bollampalli, Vishnu Priya; Sun, Meng; Chen, Yang; Amu, Sylvie; Nylén, Susanne; Eidsmo, Liv; Rothfuchs, Antonio Gigliotti; Réthi, Bence

2017-01-01

We have previously shown that human monocyte-derived dendritic cells (DCs) acquired different characteristics in dense or sparse cell cultures. Sparsity promoted the development of IL-12 producing migratory DCs, whereas dense cultures increased IL-10 production. Here we analysed whether the density-dependent endogenous breaks could modulate DC-based vaccines. Using murine bone marrow-derived DC models we show that sparse cultures were essential to achieve several key functions required for immunogenic DC vaccines, including mobility to draining lymph nodes, recruitment and massive proliferation of antigen-specific CD4+ T cells, in addition to their TH1 polarization. Transcription analyses confirmed higher commitment in sparse cultures towards T cell activation, whereas DCs obtained from dense cultures up-regulated immunosuppressive pathway components and genes suggesting higher differentiation plasticity towards osteoclasts. Interestingly, we detected a striking up-regulation of fatty acid and cholesterol biosynthesis pathways in sparse cultures, suggesting an important link between DC immunogenicity and lipid homeostasis regulation. PMID:28276533

Strength and fatigue properties of three-step sintered dense nanocrystal hydroxyapatite bioceramics

NASA Astrophysics Data System (ADS)

Guo, Wen-Guang; Qiu, Zhi-Ye; Cui, Han; Wang, Chang-Ming; Zhang, Xiao-Jun; Lee, In-Seop; Dong, Yu-Qi; Cui, Fu-Zhai

2013-06-01

Dense hydroxyapatite (HA) ceramic is a promising material for hard tissue repair due to its unique physical properties and biologic properties. However, the brittleness and low compressive strength of traditional HA ceramics limited their applications, because previous sintering methods produced HA ceramics with crystal sizes greater than nanometer range. In this study, nano-sized HA powder was employed to fabricate dense nanocrystal HA ceramic by high pressure molding, and followed by a three-step sintering process. The phase composition, microstructure, crystal dimension and crystal shape of the sintered ceramic were examined by X-ray diffraction (XRD) and scanning electron microscopy (SEM). Mechanical properties of the HA ceramic were tested, and cytocompatibility was evaluated. The phase of the sintered ceramic was pure HA, and the crystal size was about 200 nm. The compressive strength and elastic modulus of the HA ceramic were comparable to human cortical bone, especially the good fatigue strength overcame brittleness of traditional sintered HA ceramics. Cell attachment experiment also demonstrated that the ceramics had a good cytocompatibility.

Quantifying the impact of human activity on temperatures in Germany

NASA Astrophysics Data System (ADS)

Benz, Susanne A.; Bayer, Peter; Blum, Philipp

2017-04-01

Human activity directly influences ambient air, surface and groundwater temperatures. Alterations of surface cover and land use influence the ambient thermal regime causing spatial temperature anomalies, most commonly heat islands. These local temperature anomalies are primarily described within the bounds of large and densely populated urban settlements, where they form so-called urban heat islands (UHI). This study explores the anthropogenic impact not only for selected cities, but for the thermal regime on a countrywide scale, by analyzing mean annual temperature datasets in Germany in three different compartments: measured surface air temperature (SAT), measured groundwater temperature (GWT), and satellite-derived land surface temperature (LST). As a universal parameter to quantify anthropogenic heat anomalies, the anthropogenic heat intensity (AHI) is introduced. It is closely related to the urban heat island intensity, but determined for each pixel (for satellite-derived LST) or measurement point (for SAT and GWT) of a large, even global, dataset individually, regardless of land use and location. Hence, it provides the unique opportunity to a) compare the anthropogenic impact on temperatures in air, surface and subsurface, b) to find main instances of anthropogenic temperature anomalies within the study area, in this case Germany, and c) to study the impact of smaller settlements or industrial sites on temperatures. For all three analyzed temperature datasets, anthropogenic heat intensity grows with increasing nighttime lights and declines with increasing vegetation, whereas population density has only minor effects. While surface anthropogenic heat intensity cannot be linked to specific land cover types in the studied resolution (1 km × 1 km) and classification system, both air and groundwater show increased heat intensities for artificial surfaces. Overall, groundwater temperature appears most vulnerable to human activity; unlike land surface temperature and surface air temperature, groundwater temperatures are elevated in cultivated areas as well. At the surface of Germany, the highest anthropogenic heat intensity with 4.5 K is found at an open-pit lignite mine near Jülich, followed by three large cities (Munich, Düsseldorf and Nuremberg) with annual mean anthropogenic heat intensities > 4 K. Overall, surface anthropogenic heat intensities > 0 K and therefore urban heat islands are observed in communities down to a population of 5,000.

An Investigation of Taiwan's Education Regulations and Policies for Pursuing Environmental Sustainability

ERIC Educational Resources Information Center

Tsai, Wen-Tien

2012-01-01

With the rapid industrialization and economic development in the past decades, heavy environmental loads caused some serious environmental scenarios in Taiwan, an island country with a dense population and only limited natural resources. As a result, environmental education in Taiwan has been a leading tool to promote sustainable development since…

PEDV exposure protects pigs against homologous re-exposure 44 days later

USDA-ARS?s Scientific Manuscript database

Introduction PEDV emerged in the US during 2013 and rapidly spread from farm to farm causing high morbidity and mortality resulting in high economic losses to the US swine industry. As the virus made its way through swine dense populations there were many questions on degree and length of protection...

Sustainable Agriculture - Enhancing environmental benefits, food nutritional quality and building crop resilience to abiotic and biotic stresses

USDA-ARS?s Scientific Manuscript database

Feeding nutrition-dense food to future world populations presents agriculture with enormous challenges as estimates indicate that crop production must as much as double. Crop production cannot be increased to meet this challenge simply by increasing land acreage or using past agricultural intensific...

Distributions of soil phosphorus in China's densely populated village landscapes

Treesearch

Jiaguo Jiao; Erle C. Ellis; Ian Yesilonis; Junxi Wu; Hongqing Wang; Huixin Li; Linzhang Yang

2010-01-01

Purpose Village landscapes, which integrate small-scale agriculture with housing, forestry and a host of other land use practices, cover more than 2x106 km2 across China. Village lands tend to be managed at very fine spatial scales (≤30 m), with managers altering soil fertility and even terrain by terracing,...

Soil aggregation as mechanism for understanding the roles of soil biota in the sustainable usage of natural resources

USDA-ARS?s Scientific Manuscript database

Global food insecurity and rapidly diminishing water, soil, and energy resources resulting from increases in population numbers and wealth are putting pressure on agroecosystems to efficiently produce the most nutrient dense food while maintaining or enhancing natural resources. To address these ne...

CONJUGAL GENE TRANSFER IN THE RHIZOSPHERE OF WATER GRASS (ECHINOCHLORA CRUSGALLI): INFLUENCE OF ROOT EXUDATE AND BACTERIAL ACTIVITY

EPA Science Inventory

The premise that genetic exchange is primarily localized in niches characterized by dense bacterial populations and high availability of growth substrates was tested by relating conjugal gene transfer of an RP4 derivative to availability of root exudates and bacterial metabolic a...

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

ERIC Educational Resources Information Center

Hsueh, Sung-Lin; Su, Fu-Long

2016-01-01

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

Native grass seeding and forb planting establishment

Treesearch

I Nan Vance; Andrew Neill; Frank Morton

2006-01-01

After a dense stand of conifers encroaching on an oak savanna/meadow was removed, exotic forbs and grasses quickly populated the newly disturbed area. Establishing desirable native grasses and forbs that contribute to native plant diversity and compete with exotic species could aid in restoring this oak savanna plant community. Two experiments were conducted over time...

Describing the Neuron Axons Network of the Human Brain by Continuous Flow Models

NASA Astrophysics Data System (ADS)

Hizanidis, J.; Katsaloulis, P.; Verganelakis, D. A.; Provata, A.

2014-12-01

The multifractal spectrum Dq (Rényi dimensions) is used for the analysis and comparison between the Neuron Axons Network (NAN) of healthy and pathological human brains because it conveys information about the statistics in many scales, from the very rare to the most frequent network configurations. Comparison of the Fractional Anisotropy Magnetic Resonance Images between healthy and pathological brains is performed with and without noise reduction. Modelling the complex structure of the NAN in the human brain is undertaken using the dynamics of the Lorenz model in the chaotic regime. The Lorenz multifractal spectra capture well the human brain characteristics in the large negative q's which represent the rare network configurations. In order to achieve a closer approximation in the positive part of the spectrum (q > 0) two independent modifications are considered: a) redistribution of the dense parts of the Lorenz model's phase space into their neighbouring areas and b) inclusion of additive uniform noise in the Lorenz model. Both modifications, independently, drive the Lorenz spectrum closer to the human NAN one in the positive q region without destroying the already good correspondence of the negative spectra. The modelling process shows that the unmodified Lorenz model in its full chaotic regime has a phase space distribution with high fluctuations in its dense parts, while the fluctuations in the human brain NAN are smoother. The induced modifications (phase space redistribution or additive noise) moderate the fluctuations only in the positive part of the Lorenz spectrum leading to a faithful representation of the human brain axons network in all scales.

Nutrition transition, food retailing and health equity in Thailand.

PubMed

Kelly, Matthew; Banwell, Cathy; Dixon, Jane; Seubsman, Sam-Ang; Yiengprugsawan, Vasoontara; Sleigh, Adrian

2010-12-01

AIM: Here we examine the influence of changes in food retailing, the food supply and the associated nutrition transition on health equity in Thailand, a middle income country experiencing rapid economic development. METHODS: The dietary transition underway in Thailand is reviewed along with theories regarding convergence to a globalised energy dense obesogenic diet and subsequent socio-economically related dietary divergence along with the implications for health inequity. RESULTS: Thailand is part way through a dietary, nutrition and health transition. The food distribution and retailing system is now 50% controlled by modern supermarkets and convenience stores. The problem of increasing availability of calorie dense foods is especially threatening because a substantial proportion of the adult population is short statured due to child malnutrition. Obesity is an emerging problem and for educated Thai women has already developed an inverse relationship to socio-economic status as found in high income countries. CONCLUSIONS: Thailand has reached an important point in its nutrition transition. The challenge for the Thai government and population is to boost affordable healthy diets and to avoid the socio-economic inequity of nutritional outcomes observed in many rich countries.

Climate Influence on Deep Sea Populations

PubMed Central

Company, Joan B.; Puig, Pere; Sardà, Francesc; Palanques, Albert; Latasa, Mikel; Scharek, Renate

2008-01-01

Dynamics of biological processes on the deep-sea floor are traditionally thought to be controlled by vertical sinking of particles from the euphotic zone at a seasonal scale. However, little is known about the influence of lateral particle transport from continental margins to deep-sea ecosystems. To address this question, we report here how the formation of dense shelf waters and their subsequent downslope cascade, a climate induced phenomenon, affects the population of the deep-sea shrimp Aristeus antennatus. We found evidence that strong currents associated with intense cascading events correlates with the disappearance of this species from its fishing grounds, producing a temporary fishery collapse. Despite this initial negative effect, landings increase between 3 and 5 years after these major events, preceded by an increase of juveniles. The transport of particulate organic matter associated with cascading appears to enhance the recruitment of this deep-sea living resource, apparently mitigating the general trend of overexploitation. Because cascade of dense water from continental shelves is a global phenomenon, we anticipate that its influence on deep-sea ecosystems and fisheries worldwide should be larger than previously thought. PMID:18197243

Nutrition transition, food retailing and health equity in Thailand

PubMed Central

Kelly, Matthew; Banwell, Cathy; Dixon, Jane; Seubsman, Sam-ang; Yiengprugsawan, Vasoontara; Sleigh, Adrian

2012-01-01

Aim Here we examine the influence of changes in food retailing, the food supply and the associated nutrition transition on health equity in Thailand, a middle income country experiencing rapid economic development. Methods The dietary transition underway in Thailand is reviewed along with theories regarding convergence to a globalised energy dense obesogenic diet and subsequent socio-economically related dietary divergence along with the implications for health inequity. Results Thailand is part way through a dietary, nutrition and health transition. The food distribution and retailing system is now 50% controlled by modern supermarkets and convenience stores. The problem of increasing availability of calorie dense foods is especially threatening because a substantial proportion of the adult population is short statured due to child malnutrition. Obesity is an emerging problem and for educated Thai women has already developed an inverse relationship to socio-economic status as found in high income countries. Conclusions Thailand has reached an important point in its nutrition transition. The challenge for the Thai government and population is to boost affordable healthy diets and to avoid the socio-economic inequity of nutritional outcomes observed in many rich countries. PMID:22442643

Patterns of Bat Distribution and Foraging Activity in a Highly Urbanized Temperate Environment

PubMed Central

2016-01-01

Understanding how to manage biodiversity in urban areas will become increasingly important as density of humans residing in urban centers increases and urban areas expand. While considerable research has documented the shifts in biodiversity along urbanization gradients, much less work has focused on how characteristics of dense urban centers, effectively novel environments, influence behavior and biodiversity. Urban bats in San Francisco provide an opportunity to document changes in behavior and biodiversity to very high-density development. We studied (1) the distribution and abundance of bat foraging activity in natural areas; and (2) characteristics of natural areas that influence the observed patterns of distribution and foraging activity. We conducted acoustic surveys of twenty-two parks during 2008–2009. We confirmed the presence of four species of bats (Tadarida brasiliensis, Myotis yumanensis, Lasiurus blossevillii, and M. lucifugus). T. brasiliensis were found in all parks, while M. yumanensis occurred in 36% of parks. Results indicate that proximity to water, park size, and amount of forest edge best explained overall foraging activity. Proximity to water best explained species richness. M. yumanensis activity was best explained by reduced proportion of native vegetation as well as proximity to water. Activity was year round but diminished in December. We show that although bats are present even in very densely populated urban centers, there is a large reduction in species richness compared to that of outlying areas, and that most habitat factors explaining their community composition and activity patterns are similar to those documented in less urbanized environments. PMID:28030640

Impacts of land use and invasive species on native avifauna of Mo’orea, French Polynesia

PubMed Central

Furnas, Brett J.

2017-01-01

Oceanic islands are among the most endemically biodiverse ecosystems in the world. They have been adversely impacted by human expansion, which affects regional biodiversity by altering the natural habitats of vulnerable, indigenous species. Birds represent a valuable indicator species of environmental change due to their ability to adapt quickly. Investigating the relationship between environmental change, abundance, and behaviors of birds can help us better anticipate potential impacts to island ecosystems. In addition, we can understand the population trends and restricted ranges of native avifauna, identify the regions needing protection, and assess habitat vulnerability linked to anthropogenic activities. In Mo’orea, French Polynesia, we studied nine passerine bird species using automated acoustic recording devices placed in agricultural, forested, and mixed habitats. Based on call counts per unit time and occupancy modeling, we found evidence that three non-native species preferred agricultural areas and low-canopy cover over dense forested areas. Furthermore, native bird detectability and possibly abundance was significantly lower than non-native birds. Using hierarchical cluster analysis to support inferences regarding behavioral differences, we found that native bird calling activity was negatively associated with non-native bird calling activity. Altogether, these results suggest native bird populations are at risk in all of the habitats studied, but forests serve as a potential refuge. PMID:28929014

Source, Use, and Disposition of Freshwater in Puerto Rico, 2005

USGS Publications Warehouse

Molina-Rivera, Wanda L.

2010-01-01

Water diverted from streams and pumped from wells constitutes the main sources of water for the 78 municipios of the Commonwealth of Puerto Rico. A better understanding is needed about water-use patterns, particularly about the amount of water used, where and how this water is used and disposed, and how human activities impact water resources. Irrigation practices, indoor and outdoor household uses, industrial uses, and commercial and mining withdrawals affect reservoirs, streams, and aquifers. Accurate and accessible water information for Puerto Rico is critical to ensure that water managers have the ability to protect and conserve this natural resource. The population of Puerto Rico increased 15 percent, from 3.4 million in 1985 to 3.9 million people 2005 and resulted in an increased demand for freshwater, mostly for the public-supply water use category. Almost 99 percent of the residents in Puerto Rico were served by public-supply water systems in 2005. One of the major challenges that water managers confront is the need to provide sufficient freshwater availability in the densely populated areas. Public-supply water is provided by the Puerto Rico Aqueducts and Sewers Authority (PRASA) and by non-PRASA systems. Non-PRASA systems refer to community-operated water systems (water systems that serve a rural or suburban housing area).

Mapping risk of avian influenza transmission at the interface of domestic poultry and wild birds

USGS Publications Warehouse

Prosser, Diann J.; Hungerford, Laura L.; Erwin, R. Michael; Ottinger, Mary Ann; Takekawa, John Y.; Ellis, Erle C.

2013-01-01

Emergence of avian influenza viruses with high lethality to humans, such as the currently circulating highly pathogenic A(H5N1) (emerged in 1996) and A(H7N9) cause serious concern for the global economic and public health sectors. Understanding the spatial and temporal interface between wild and domestic populations, from which these viruses emerge, is fundamental to taking action. This information, however, is rarely considered in influenza risk models, partly due to a lack of data. We aim to identify areas of high transmission risk between domestic poultry and wild waterfowl in China, the epicenter of both viruses. Two levels of models were developed: one that predicts hotspots of novel virus emergence between domestic and wild birds, and one that incorporates H5N1 risk factors, for which input data exists. Models were produced at 1 and 30 km spatial resolution, and two temporal seasons. Patterns of risk varied between seasons with higher risk in the northeast, central-east, and western regions of China during spring and summer, and in the central and southeastern regions during winter. Monte-Carlo uncertainty analyses indicated varying levels of model confidence, with lowest errors in the densely populated regions of eastern and southern China. Applications and limitations of the models are discussed within.

Joint representation of consistent structural and functional profiles for identification of common cortical landmarks.

PubMed

Zhang, Shu; Zhao, Yu; Jiang, Xi; Shen, Dinggang; Liu, Tianming

2018-06-01

In the brain mapping field, there have been significant interests in representation of structural/functional profiles to establish structural/functional landmark correspondences across individuals and populations. For example, from the structural perspective, our previous studies have identified hundreds of consistent DICCCOL (dense individualized and common connectivity-based cortical landmarks) landmarks across individuals and populations, each of which possess consistent DTI-derived fiber connection patterns. From the functional perspective, a large collection of well-characterized HAFNI (holistic atlases of functional networks and interactions) networks based on sparse representation of whole-brain fMRI signals have been identified in our prior studies. However, due to the remarkable variability of structural and functional architectures in the human brain, it is challenging for earlier studies to jointly represent the connectome-scale structural and functional profiles for establishing a common cortical architecture which can comprehensively encode both structural and functional characteristics across individuals. To address this challenge, we propose an effective computational framework to jointly represent the structural and functional profiles for identification of consistent and common cortical landmarks with both structural and functional correspondences across different brains based on DTI and fMRI data. Experimental results demonstrate that 55 structurally and functionally common cortical landmarks can be successfully identified.

Nutrition Economics: How to Eat Better for Less.

PubMed

Drewnowski, Adam

2015-01-01

Food prices and diet costs contribute to socioeconomic disparities in diet quality and health. Lower-cost diets provide ample calories but lack essential nutrients. Nutrition economics can remedy health disparities by helping to identify food patterns that are nutrient-rich, affordable, and appealing. First, nutrient profiling models--such as the Nutrient Rich Food (NRF) family of indices--are able to separate foods that are energy-dense from those that are nutrient-rich. Whereas energy-dense foods contain more calories than nutrients, nutrient-rich foods contain more nutrients than calories. Second, new value metrics have identified affordable healthy foods, based on nutrients per unit cost. Third, these methods have now been applied to the analyses of individual foods and beverages, meals, menus, and the total diet. The Healthy Eating Index (HEI), based on compliance with dietary guidelines, was the principal measure of total diet quality. Although healthier diets did generally cost more, some population subgroups managed to obtain nutrient-dense diets at a lower cost. Being able to create affordable, healthy food patterns on limited budgets is an example of nutrition resilience.

Intermittent turbulence in flowing bacterial suspensions

PubMed Central

Secchi, Eleonora; Rusconi, Roberto; Buzzaccaro, Stefano; Salek, M. Mehdi; Smriga, Steven; Piazza, Roberto; Stocker, Roman

2016-01-01

Dense suspensions of motile bacteria, possibly including the human gut microbiome, exhibit collective dynamics akin to those observed in classic, high Reynolds number turbulence with important implications for chemical and biological transport, yet this analogy has remained primarily qualitative. Here, we present experiments in which a dense suspension of Bacillus subtilis bacteria was flowed through microchannels and the velocity statistics of the flowing suspension were quantified using a recently developed velocimetry technique coupled with vortex identification methods. Observations revealed a robust intermittency phenomenon, whereby the average velocity profile of the suspension fluctuated between a plug-like flow and a parabolic flow profile. This intermittency is a hallmark of the onset of classic turbulence and Lagrangian tracking revealed that it here originates from the presence of transient vortices in the active, collective motion of the bacteria locally reinforcing the externally imposed flow. These results link together two entirely different manifestations of turbulence and show the potential of the microfluidic approach to mimic the environment characteristic of certain niches of the human microbiome. PMID:27307513

Intermittent turbulence in flowing bacterial suspensions.

PubMed

Secchi, Eleonora; Rusconi, Roberto; Buzzaccaro, Stefano; Salek, M Mehdi; Smriga, Steven; Piazza, Roberto; Stocker, Roman

2016-06-01

Dense suspensions of motile bacteria, possibly including the human gut microbiome, exhibit collective dynamics akin to those observed in classic, high Reynolds number turbulence with important implications for chemical and biological transport, yet this analogy has remained primarily qualitative. Here, we present experiments in which a dense suspension of Bacillus subtilis bacteria was flowed through microchannels and the velocity statistics of the flowing suspension were quantified using a recently developed velocimetry technique coupled with vortex identification methods. Observations revealed a robust intermittency phenomenon, whereby the average velocity profile of the suspension fluctuated between a plug-like flow and a parabolic flow profile. This intermittency is a hallmark of the onset of classic turbulence and Lagrangian tracking revealed that it here originates from the presence of transient vortices in the active, collective motion of the bacteria locally reinforcing the externally imposed flow. These results link together two entirely different manifestations of turbulence and show the potential of the microfluidic approach to mimic the environment characteristic of certain niches of the human microbiome. © 2016 The Author(s).

Wild pig populations in the National Parks

NASA Astrophysics Data System (ADS)

Singer, Francis J.

1981-05-01

Populations of introduced European wild boar, feral pigs, and combinations of both types (all Sus scrola L.) inhabit thirteen areas in the National Park Service system. All parks have relatively stable populations, with the exception of Great Smoky Mountains National Park, which reported a rapidly expanding wild boar population. Suspected and documented impacts were apparently related to pig densities and sensitivity of the ecosystem; the three largest units with dense wild pig populations reported the most damage. Overall, wild pigs are a relatively minor problem for the Park Service; however, problems are severe in at least three parks, and there is potential for invasion of wild boars into several additional parks in the Appalachian Mountains. More specific information is needed on numbers of wild pigs and their impacts in the various parks.

The need for calcium imaging in nonhuman primates: New motor neuroscience and brain-machine interfaces.

PubMed

O'Shea, Daniel J; Trautmann, Eric; Chandrasekaran, Chandramouli; Stavisky, Sergey; Kao, Jonathan C; Sahani, Maneesh; Ryu, Stephen; Deisseroth, Karl; Shenoy, Krishna V

2017-01-01

A central goal of neuroscience is to understand how populations of neurons coordinate and cooperate in order to give rise to perception, cognition, and action. Nonhuman primates (NHPs) are an attractive model with which to understand these mechanisms in humans, primarily due to the strong homology of their brains and the cognitively sophisticated behaviors they can be trained to perform. Using electrode recordings, the activity of one to a few hundred individual neurons may be measured electrically, which has enabled many scientific findings and the development of brain-machine interfaces. Despite these successes, electrophysiology samples sparsely from neural populations and provides little information about the genetic identity and spatial micro-organization of recorded neurons. These limitations have spurred the development of all-optical methods for neural circuit interrogation. Fluorescent calcium signals serve as a reporter of neuronal responses, and when combined with post-mortem optical clearing techniques such as CLARITY, provide dense recordings of neuronal populations, spatially organized and annotated with genetic and anatomical information. Here, we advocate that this methodology, which has been of tremendous utility in smaller animal models, can and should be developed for use with NHPs. We review here several of the key opportunities and challenges for calcium-based optical imaging in NHPs. We focus on motor neuroscience and brain-machine interface design as representative domains of opportunity within the larger field of NHP neuroscience. Copyright © 2016 The Authors. Published by Elsevier Inc. All rights reserved.

Peri-urbanisation, counter-urbanisation, and an extension of residential exposure to ticks: a clue to the trends in Lyme borreliosis incidence in the Czech Republic?

PubMed

Zeman, Petr; Benes, Cestmir

2014-10-01

The incidence of tick-borne human diseases (TBD) in the Czech Republic (CZ) is on the increase, driven by infections increasingly acquired in residential locations, earlier in spring and later in autumn, and among children and the elderly. To interpret these trends, data on Lyme borreliosis (LB) incidence between 1997 and 2010 were analysed in the context of population migration flows registered in the CZ during the same period. Analysis showed that a migration stream of families with children, and of the elderly, flowed from more urbanized and densely populated localities to those more rural and less populated, where the chance of acquiring LB in the home vicinity was greater than in the urban settings. By contrast, a stream of people in the life phase between early adulthood and family formation flowed reversely, corresponding to a prominent absence of this age category from the patient spectrum. The data further showed that the more the residential exposure became prevalent, the more people were in year-round (rather than in summertime only) contact with ticks, which accounts for an extension of the cases' seasonal distribution as well as for an overall increase in case numbers. Finally, the fact that majority of the urban-to-rural migrants could be categorised as wealthier people could explain the previously noticed lack of low-status people among TBD patients in the CZ. Copyright © 2014 Elsevier GmbH. All rights reserved.

TENOGENIC DIFFERENTIATION OF HUMAN MSCs INDUCED BY THE TOPOGRAPHY OF ELECTROCHEMICALLY ALIGNED COLLAGEN THREADS

PubMed Central

Kishore, Vipuil; Bullock, Whitney; Sun, Xuanhao; Van Dyke, William Scott; Akkus, Ozan

2011-01-01

Topographical cues from the extracellular microenvironment can influence cellular activity including proliferation and differentiation. Information on the effects of material topography on tenogenic differentiation of human mesenchymal stem cells (human MSCs) is limited. A methodology using the principles of isoelectric focusing has previously been developed in our laboratory to synthesize electrochemically aligned collagen (ELAC) threads that mimics the packing density, alignment and strength of collagen dense connective tissues. In the current study, human MSCs were cultured on ELAC and randomly-oriented collagen threads and the effect of collagen orientation on cell morphology, proliferation and tenogenic differentiation was investigated. The results indicate that higher rates of proliferation were observed on randomly oriented collagen threads compared to ELAC threads. On the other hand, tendon specific markers such as scleraxis, tenomodulin, tenascin-C and collagen-III were significantly increased on ELAC threads compared to randomly oriented collagen threads. Additionally, osteocalcin, a specific marker of bone differentiation was suppressed on ELAC threads. Previous studies have reported that BMP-12 is a key growth factor to induce tenogenic differentiation of human MSCs. To evaluate the synergistic effect of BMP-12 and collagen orientation, human MSCs were cultured on ELAC threads in culture medium supplemented with and without BMP-12. The results revealed that BMP-12 did not have an additional effect on the tenogenic differentiation of human MSCs on ELAC threads. Together, these results suggest that ELAC induces tenogenic differentiation of human MSCs by presenting an aligned and dense collagen substrate, akin to the tendon itself. In conclusion, ELAC has a significant potential to be used as a tendon replacement and in the development of an osteotendinous construct towards the regeneration of bone-tendon interfaces. PMID:22177622

Study the Synthesis, Characterization and Immersion of Dense and Porous Bovine Hydroxyapatite Structures in Hank's Balanced Salt Solution

NASA Astrophysics Data System (ADS)

Eslami, N.; Mahmoodian, R.; Hamdi, M.; Khatir, Nadia Mahmoudi; Herliansyah, M. K.; Rafieerad, Ali Reza

2017-04-01

The bone-bonding potential of biomaterials is evaluated in vitro through examining the surface apatite formation in Hank's media to enhance biocompatibility, which is also applicable to facilitate in vivo osseointegration of implantable devices. Hence, bovine hydroxyapatite (BHA) bioceramic structures have been used in various biomedical applications such as orthopedic implants. In this article, the microstructure, in vitro bioactivity, and nanomechanical properties of the synthesized dense and porous BHA are investigated via scanning electron microscopy, x-ray diffraction, energy-dispersive x-ray spectroscopy, Fourier transform infrared spectroscopy, and nanoindentation analysis. From the obtained results, porous BHA mostly possesses adequate requirements for substitution as implants in the human body.

Impact of land use and land cover changes on the ambient temperature in a middle scale city, Takamatsu, in Southwest Japan.

PubMed

Nonomura, Atsuko; Kitahara, Mutsuko; Takuro Masuda

2009-08-01

There is a lack of information on urban heat island impact on the thermal environment due to low populated urban sprawl, although densely populated urban sprawl impact has been identified by several researchers. The Takamatsu area has recently developed in a low populated urban sprawl style without any increase in population. This paper examined the impact of a low populated urban sprawl on the thermal environment through an analysis of the last 30 years data set and investigated the contribution of vegetation fraction and population density to the temperature trend. As a consequence, it was shown that one of the most significant causative factors of temperature increase is an expansion of non-vegetated area even without population growth. This result implied that vegetated zones should be maintained in urban areas in order to realize sustainable urbanization.

A stranger to our camps: Typhus in American history.

PubMed

Humphreys, Margaret

2006-01-01

Medical observers during the American Civil War were happily surprised to find that typhus fever rarely made an appearance, and was not a major killer in the prisoner-of-war camps where the crowded, filthy, and malnourished populations appeared to offer an ideal breeding ground for the disease. Through a review of apparent typhus outbreaks in America north of the Mexican border, this article argues that typhus fever rarely if ever extended to the established populations of the United States, even when imported on immigrant ships into densely populated and unsanitary slums. It suggests that something in the American environment was inhospitable to the extensive spread of the disease, most likely an unrecognized difference in the North American louse population compared to that of Europe.

Ramsey scheme for coherent population resonance detection in the optically dense medium

NASA Astrophysics Data System (ADS)

Barantsev, Konstantin; Litvinov, Andrey; Popov, Evgeniy

2018-04-01

This work is devoted to a theoretical investigation of the Ramsey method of detection of the coherent population trapping resonance in cold atomic clouds taking into account collective effects caused by finite optical depth of the considered clouds. The interaction of atoms with pulsed laser radiation is described in the formalism of density matrix by means of Maxwell-Bloch set of equations. The Ramsey signal of coherent population trapping resonance was calculated for the radiation passed through the medium and analyzed for different length of the atomic cloud. Also the population of excited level was calculated in dependence on the two-photon detuning and coordinate along the main optical axis. The light shift of sidebands and appearance of additional harmonics were discovered.

Improving selenium nutritional value of major crops

USDA-ARS?s Scientific Manuscript database

Micronutrient efficiency and development of nutrient-dense crops continue to be one of the most important global challenges. Se is an essential micronutrient to humans and serves as a cancer preventative agent. In order to improve Se nutritional and health promoting values in food crops, a better un...

Exploring the functional side of the Ocean Sampling Day metagenomes

NASA Astrophysics Data System (ADS)

Antonio, F. G.; Kottmann, R.; Wallom, D.; Glöckner, F. O.

2016-02-01

The Ocean Sampling Day (OSD) is a simultaneous, collaborative, standardized, and global mega-sequencing campaign to analyze marine microbial community composition and functional traits. 150 metagenomes were sequenced from the first OSD in June 2014 including a rich set of environmental and oceanographic measurements. Unlike other ocean mega-surveys such as Global Ocean Sampling (GOS) or the TARA expedition that mostly sampled open ocean waters most of the OSD samples are from coastal sampling sites, an area not previously well studied in this regard. The result is that OSD adds more than three million new genes to the recently published Ocean Microbial-Reference Gene Catalog (Sunawaga et al., 2015). This allows us to significantly increase our knowledge of the ocean microbiome, identify hot-spots of novelty in terms of function and investigate the impact of human activities on oceans coastal areas where there is the largest interaction between dense human populations and the marine world. Additionally, these cumulative samples, related in time, space and environmental parameters, are providing insights into fundamental rules describing microbial diversity and function and contribute to the blue economy through the identification of novel ocean-derived biotechnologies. References: Sunagawa, Coelho, Chaffron, et al. (2015, May). Structure and function of the global ocean microbiome. Science, 348(6237), 126135.

Molecular epidemiology and evolutionary genetics of Mycobacterium tuberculosis in Taipei.

PubMed

Dou, Horng-Yunn; Tseng, Fan-Chen; Lin, Chih-Wei; Chang, Jia-Ru; Sun, Jun-Ren; Tsai, Wen-Shing; Lee, Shi-Yi; Su, Ih-Jen; Lu, Jang-Jih

2008-12-22

The control of tuberculosis in densely populated cities is complicated by close human-to-human contacts and potential transmission of pathogens from multiple sources. We conducted a molecular epidemiologic analysis of 356 Mycobacterium tuberculosis (MTB) isolates from patients presenting pulmonary tuberculosis in metropolitan Taipei. Classical antibiogram studies and genetic characterization, using mycobacterial interspersed repetitive-unit-variable-number tandem-repeat (MIRU-VNTR) typing and spoligotyping, were applied after culture. A total of 356 isolates were genotyped by standard spoligotyping and the strains were compared with in the international spoligotyping database (SpolDB4). All isolates were also categorized using the 15 loci MIRU-VNTR typing method and combin with NTF locus and RD deletion analyses. Of 356 isolates spoligotyped, 290 (81.4%) displayed known spoligotypes and 66 were not identified in the database. Major spoligotypes found were Beijing lineages (52.5%), followed by Haarlem lineages (13.5%) and EAI plus EAI-like lineages (11%). When MIRU-VNTR was employed, 140 patterns were identified, including 36 clusters by 252 isolates and 104 unique patterns, and the largest cluster comprised 95 isolates from the Beijing family. The combination of spoligotyping and MIRU-VNTR revealed that 236 (67%) of the 356 isolates were clustered in 43 genotypes. Strains of the Beijing family was more likely to be of modern strain and a higher percentage of multiple drug resistance than other families combined (P = 0.08). Patients infected with Beijing strains were younger than those with other strains (mean 58.7 vs. 64.2, p = 0.02). Moreover, 85.3% of infected persons younger than 25 years had Beijing modern strain, suggesting a possible recent spread in the young population by this family of TB strain in Taipei. Our data on MTB genotype in Taipei suggest that MTB infection has not been optimally controlled. Control efforts should be reinforced in view of the high prevalence of the Beijing strain in young population and association with drug resistance.

Molecular epidemiology and evolutionary genetics of Mycobacterium tuberculosis in Taipei

PubMed Central

Dou, Horng-Yunn; Tseng, Fan-Chen; Lin, Chih-Wei; Chang, Jia-Ru; Sun, Jun-Ren; Tsai, Wen-Shing; Lee, Shi-Yi; Su, Ih-Jen; Lu, Jang-Jih

2008-01-01

Background The control of tuberculosis in densely populated cities is complicated by close human-to-human contacts and potential transmission of pathogens from multiple sources. We conducted a molecular epidemiologic analysis of 356 Mycobacterium tuberculosis (MTB) isolates from patients presenting pulmonary tuberculosis in metropolitan Taipei. Classical antibiogram studies and genetic characterization, using mycobacterial interspersed repetitive-unit-variable-number tandem-repeat (MIRU-VNTR) typing and spoligotyping, were applied after culture. Methods A total of 356 isolates were genotyped by standard spoligotyping and the strains were compared with in the international spoligotyping database (SpolDB4). All isolates were also categorized using the 15 loci MIRU-VNTR typing method and combin with NTF locus and RD deletion analyses. Results Of 356 isolates spoligotyped, 290 (81.4%) displayed known spoligotypes and 66 were not identified in the database. Major spoligotypes found were Beijing lineages (52.5%), followed by Haarlem lineages (13.5%) and EAI plus EAI-like lineages (11%). When MIRU-VNTR was employed, 140 patterns were identified, including 36 clusters by 252 isolates and 104 unique patterns, and the largest cluster comprised 95 isolates from the Beijing family. The combination of spoligotyping and MIRU-VNTR revealed that 236 (67%) of the 356 isolates were clustered in 43 genotypes. Strains of the Beijing family was more likely to be of modern strain and a higher percentage of multiple drug resistance than other families combined (P = 0.08). Patients infected with Beijing strains were younger than those with other strains (mean 58.7 vs. 64.2, p = 0.02). Moreover, 85.3% of infected persons younger than 25 years had Beijing modern strain, suggesting a possible recent spread in the young population by this family of TB strain in Taipei. Conclusion Our data on MTB genotype in Taipei suggest that MTB infection has not been optimally controlled. Control efforts should be reinforced in view of the high prevalence of the Beijing strain in young population and association with drug resistance. PMID:19102768

Hydroarchaeology: Measuring the Ancient Human Impact on the Palenque Watershed

NASA Astrophysics Data System (ADS)

French, K. D.; Duffy, C. J.

2010-03-01

Palenque, one of the best known Classic Maya centers, has what is arguably the most unique and intricate system of water management known anywhere in the Maya Lowlands. Years of archaeological research, including intensive mapping between 1997 and 2000, reveal that this major center, situated on a narrow escarpment at the base of a high mountain range in northern Chiapas, Mexico, began as a modest settlement about AD 100. Then, during the seventh and eighth centuries, Palenque experienced explosive growth, mushrooming into a dense community with an estimated population of 6000 and approximately 1500 structures — residences, palaces, and temples¬ - under a series of powerful rulers. This process of "urban" growth led to obvious changes in landcover. In order to better understand the effects that landcover and climate change have on the availability of water for an ancient city a new approach is required. In this paper we explore a hydroarchaeological approach that utilizes simulated daily paleoclimate data, watershed modeling, and traditional archaeology to view the response of ancient human impact within the watershed surrounding Palenque. There is great potential for watershed-climate modeling in developing plausible scenarios of water use and supply, and the effect of extreme conditions (flood and drought), all of which cannot be fully represented by atmosphere-based climate and weather projections. The first objective of the paper is to test the hypothesis that drought was a major cause for Palenque’s collapse. Did the Maya abandon Palenque in search of water? Secondly, we evaluate the hydraulic design of the water management features at Palenque against extreme meteorological events. How successful was the hydraulic engineering of the Maya in coping with droughts and floods? The archaeological implications for this non-invasive "virtual" method are many, including detecting periods of stress within a community, estimating population by developing caps based on the availability of water, understanding settlement patterns, as well as assisting present local populations in understanding the water cycle of Palenque.

Species richness, distribution and genetic diversity of Caenorhabditis nematodes in a remote tropical rainforest

PubMed Central

2013-01-01

Background In stark contrast to the wealth of detail about C. elegans developmental biology and molecular genetics, biologists lack basic data for understanding the abundance and distribution of Caenorhabditis species in natural areas that are unperturbed by human influence. Methods Here we report the analysis of dense sampling from a small, remote site in the Amazonian rain forest of the Nouragues Natural Reserve in French Guiana. Results Sampling of rotting fruits and flowers revealed proliferating populations of Caenorhabditis, with up to three different species co-occurring within a single substrate sample, indicating remarkable overlap of local microhabitats. We isolated six species, representing the highest local species richness for Caenorhabditis encountered to date, including both tropically cosmopolitan and geographically restricted species not previously isolated elsewhere. We also documented the structure of within-species molecular diversity at multiple spatial scales, focusing on 57 C. briggsae isolates from French Guiana. Two distinct genetic subgroups co-occur even within a single fruit. However, the structure of C. briggsae population genetic diversity in French Guiana does not result from strong local patterning but instead presents a microcosm of global patterns of differentiation. We further integrate our observations with new data from nearly 50 additional recently collected C. briggsae isolates from both tropical and temperate regions of the world to re-evaluate local and global patterns of intraspecific diversity, providing the most comprehensive analysis to date for C. briggsae population structure across multiple spatial scales. Conclusions The abundance and species richness of Caenorhabditis nematodes is high in a Neotropical rainforest habitat that is subject to minimal human interference. Microhabitat preferences overlap for different local species, although global distributions include both cosmopolitan and geographically restricted groups. Local samples for the cosmopolitan C. briggsae mirror its pan-tropical patterns of intraspecific polymorphism. It remains an important challenge to decipher what drives Caenorhabditis distributions and diversity within and between species. PMID:23311925

Environmental migration and conflict dynamics: focus on developing regions.

PubMed

Swain, A

1996-12-01

The world's population is increasing by 90-100 million every year, and it may double during the next half-century, with most of the added population coming from developing countries. 700 million people are malnourished and 40,000 die of hunger and hunger-related diseases each day. Most of the developing countries are extremely dependent on their renewable resource base to sustain their economic activities. Therefore, environmental changes and the loss of resources has dire implications for developing countries. This includes loss of arable land and lack of water, which lead to decreased food production. An area of about 1.2 billion hectares (almost the size of China and India taken together) has endured modest to severe soil degradation since World War II because of human activity. Air pollution can also directly affect crop production, lowering crop, wheat, soybean, and peanut harvests in the US. Rapid climate change triggered by the greenhouse effect would also inflict disproportionately more suffering on developing countries. The rise in sea levels caused by climatic change may severely affect densely populated coastal areas in China, Egypt, and Bangladesh. The loss of living space and livelihood could lead to the migration of people as it has happened throughout human history. The definition of environmental migrants is controversial and the other terms used include environmental refugees, ecological refugees, and resource refugees. Economic migrants are those who move to economically affluent regions responding to both the push and pull factors. In contrast, environmental migrants are forced to move--as a result of the loss of livelihood and space--to the nearest possible location. The scarcity induced by environmental migration may lead to acute conflict at three levels in the developing society: state vs. state (large-scale trans-border migration may trigger armed conflicts); state vs. group (rapid urbanization); and group vs. group (nativism).

Identifying anthropogenic anomalies in air, surface and groundwater temperatures in Germany.

PubMed

Benz, Susanne A; Bayer, Peter; Blum, Philipp

2017-04-15

Human activity directly influences ambient air, surface and groundwater temperatures. The most prominent phenomenon is the urban heat island effect, which has been investigated particularly in large and densely populated cities. This study explores the anthropogenic impact on the thermal regime not only in selected urban areas, but on a countrywide scale for mean annual temperature datasets in Germany in three different compartments: measured surface air temperature, measured groundwater temperature, and satellite-derived land surface temperature. Taking nighttime lights as an indicator of rural areas, the anthropogenic heat intensity is introduced. It is applicable to each data set and provides the difference between measured local temperature and median rural background temperature. This concept is analogous to the well-established urban heat island intensity, but applicable to each measurement point or pixel of a large, even global, study area. For all three analyzed temperature datasets, anthropogenic heat intensity grows with increasing nighttime lights and declines with increasing vegetation, whereas population density has only minor effects. While surface anthropogenic heat intensity cannot be linked to specific land cover types in the studied resolution (1km×1km) and classification system, both air and groundwater show increased heat intensities for artificial surfaces. Overall, groundwater temperature appears most vulnerable to human activity, albeit the different compartments are partially influenced through unrelated processes; unlike land surface temperature and surface air temperature, groundwater temperatures are elevated in cultivated areas as well. At the surface of Germany, the highest anthropogenic heat intensity with 4.5K is found at an open-pit lignite mine near Jülich, followed by three large cities (Munich, Düsseldorf and Nuremberg) with annual mean anthropogenic heat intensities >4K. Overall, surface anthropogenic heat intensities >0K and therefore urban heat islands are observed in communities down to a population of 5000. Copyright © 2017 Elsevier B.V. All rights reserved.

Microbial populations and activities in the rhizoplane of rock-weathering desert plants. I. root colonization and weathering of igneous rocks.

Treesearch

M.E. Puente; Y. Bashan; C.Y. Li; V.K. Lebsky

2004-01-01

Dense layers of bacteria and fungi in the rhizoplane of three species of cactus (Pachycereus pringlei, Stenocereus thurberi, Opuntia cholla) and a wild fig tree (Ficus palmeri) growing in rocks devoid of soil were revealed by bright-field and fluorescence microscopy and field emission...

Microfluidic Device

NASA Technical Reports Server (NTRS)

Tai, Yu-Chong (Inventor); Kasdan, Harvey L. (Inventor); Zheng, Siyang (Inventor); Lin, Jeffrey Chun-Hui (Inventor)

2016-01-01

Described herein are particular embodiments relating to a microfluidic device that may be utilized for cell sensing, counting, and/or sorting. Particular aspects relate to a microfabricated device that is capable of differentiating single cell types from dense cell populations. One particular embodiment relates a device and methods of using the same for sensing, counting, and/or sorting leukocytes from whole, undiluted blood samples.

Microfluidic Device

NASA Technical Reports Server (NTRS)

Zheng, Siyang (Inventor); Lin, Jeffrey Chun-Hui (Inventor); Kasdan, Harvey (Inventor); Tai, Yu-Chong (Inventor)

2015-01-01

Described herein are particular embodiments relating to a microfluidic device that may be utilized for cell sensing, counting, and/or sorting. Particular aspects relate to a microfabricated device that is capable of differentiating single cell types from dense cell populations. One particular embodiment relates a device and methods of using the same for sensing, counting, and/or sorting leukocytes from whole, undiluted blood samples.

Characterization of bacterial diversity at different depths in the Moravia Hill landfill site at Medellin, Colombia

USDA-ARS?s Scientific Manuscript database

A combination of culture-dependent and culture-independent methods was used to assess bacterial diversity at different depths within a former solid waste dump in Medellín, Colombia. Sampling sites included a densely populated area, which is built upon 40 m of solid waste (domestic, industrial, agric...

Management of western coniferous forest habitat for nesting accipiter hawks

Treesearch

Richard T. Reynolds

1983-01-01

Availability of nesting sites can limit accipiter populations. Because accipiters nest in dense forest stands, any alteration that opens these stands is likely to lessen their desirability as nest sites. Tree growth and the associated changes in the vegetative structure of aging nest sites limit the number of years sites will be suitable. Therefore, prospective...

Estimating abundance of Sitka black-tailed deer using DNA from fecal pellets

Treesearch

Todd J. Brinkman; David K. Person; F. Stuart Chapin; Winston Smith; Kris J. Hundertmark

2011-01-01

Densely vegetated environments have hindered collection of basic population parameters on forest-dwelling ungulates. Our objective was to develop a mark-recapture technique that used DNA from fecal pellets to overcome constraints associated with estimating abundance of ungulates in landscapes where direct observation is difficult. We tested our technique on Sitka black...

Messages for Educational Leadership: The Constance E. Clayton Lectures 1998-2007. Black Studies and Critical Thinking. Volume 34

ERIC Educational Resources Information Center

Slaughter-Defoe, Diana T., Ed.

2012-01-01

Urban education is an interdisciplinary field, characterized by introducing many perspectives to research pertaining to educational policy and to the practice of educating youth whose lives unfold in densely populated urban metropolitan areas. This book celebrates Constance Clayton's eleven-year tenure as superintendent of the School District of…

Microfluidic Device

NASA Technical Reports Server (NTRS)

Tai, Yu-Chong (Inventor); Zheng, Siyang (Inventor); Lin, Jeffrey Chun-Hui (Inventor); Kasdan, Harvey L. (Inventor)

2017-01-01

Described herein are particular embodiments relating to a microfluidic device that may be utilized for cell sensing, counting, and/or sorting. Particular aspects relate to a microfabricated device that is capable of differentiating single cell types from dense cell populations. One particular embodiment relates a device and methods of using the same for sensing, counting, and/or sorting leukocytes from whole, undiluted blood samples.

NEW YORK-NEW JERSEY HARBOR ESTUARY PROGRAM INCLUDING THE BIGHT RESTORATION PLAN FINAL COMPREHENSIVE CONSERVATION AND MANAGEMENT PLAN

EPA Science Inventory

New York-New Jersey Harbor and the New York Bight are extraordinary in many ways -- their abundant resources, their beauty, and their many competing uses. The Harbor/Bight abounds with diverse natural resources, yet it is the heart of the most densely populated region of the nati...

Condition varies with habitat choice in postbreeding forest birds

Treesearch

Scott H. Stoleson

2013-01-01

Many birds that are experiencing population declines require extensive tracts of mature forest habitat for breeding. Recent work suggests that at least some may shift their habitat use to early-successional areas after nesting but before migration. I used constant-effort mist netting in regenerating clearcuts (4-8 years postcut) and dense mature-forest understories to...

Enhancing the Value and Sustainability of Field Stations and Marine Laboratories in the 21st Century

ERIC Educational Resources Information Center

National Academies Press, 2014

2014-01-01

For over a century, field stations have been important entryways for scientists to study and make important discoveries about the natural world. They are centers of research, conservation, education, and public outreach, often embedded in natural environments that range from remote to densely populated urban locations. Because they lack…

INFLUENCE OF ROOT EXUDATES AND BACTERIAL METABOLIC ACTIVITY ON APPARENT CONJUGAL GENE TRANSFER FREQUENCIES IN THE RHIZOSPHERE OF WATER GRASS (ECHINOCLORA CRUSGALLI)

EPA Science Inventory

The premise that genetic exchange is primarily localized in niches characterized by dense bacterial populations and high availability of growth substrates was tested by relating conjugal gene transfer of an RP4 derivative to availability of root exudates and bacterial metabolic a...

The impact of roads on the timber rattlesnake (Crotalus horridus) in eastern Texas

Treesearch

D. Craig Rudolph; Shirley J. Burgdorf; Richard N. Conner; James G. Dickson

1998-01-01

Roads and associated vehicular traffic have the potential to significantly impact vertebrate populations. In eastern Texas we compared the densities of paved and unpaved roads within 2 and 4 km radii of timber rattlesnake (Crotalus horridus) ocations and of random points. Road networks were significantly more dense at random points than at snake...

Solo but Not Separate: Preparing 21st-Century School Library Professionals Who Can "Go It Alone"

ERIC Educational Resources Information Center

Pasco, Becky

2011-01-01

Preparing school librarians for a diverse array of 21st-century educational environments is a daunting task. Faculty in school library preparation programs send candidates out into sparsely populated rural areas, dense urban settings, and everything in between. Some candidates will provide services and resources in updated, modern facilities,…

Constructing nature as constructing science: expertise, activist science, and public conflict in the Chicago wilderness

Treesearch

Reid M. Helford

2000-01-01

In April 1996 an exciting new project was announced, an unprecedented conservation undertaking in one of the nation's most densely populated regions. Chicago Wilderness is a collaborative effort among the more than 90 organizations that make up the Chicago Region Biodiversity Council (CRBC) to protect, restore, and manage the region's natural landscapes...

Images of the "Other" with "Alien" Ethnicity in the Conscience of Russian Population Living in Border Regions

ERIC Educational Resources Information Center

Omelchenko, Daria A.; Maximova, Svetlana G.; Noyanzina, Oksana E.; Maximov, Maxim B.; Avdeeva, Galina S.

2016-01-01

In the age of dense international relations, heightened by intensive migration flows and local ethnic identity strengthening, the study of social representations of ethnic "others" in public consciousness permit to fulfill the evaluation of the current interethnic situation in the country, explore the latent unconscious groundings for…

Linking human nutrition and fisheries: incorporating micronutrient-dense, small indigenous fish species in carp polyculture production in Bangladesh.

PubMed

Roos, Nanna; Wahab, M Abdul; Hossain, Mostafa Ali Reza; Thilsted, Shakuntala Haraksingh

2007-06-01

Fish and fisheries are important for the livelihoods, food, and income of the rural population in Bangladesh. Increased rice production and changing agricultural patterns have resulted in a large decline in inland fisheries. Implementation of carp pond polyculture has been very successful, whereas little focus has been given to the commonly consumed small indigenous fish species, some of which are rich in vitamin A and minerals, such as calcium, iron, and zinc, and are an integral part of the rural diet. The overall objective of the research and capacity-building activities described in this paper is to increase the production, accessibility, and intake of nutrient-dense small indigenous fish species, in particular mola (Amblypharyngodon mola), in order to combat micronutrient deficiencies. The large contribution from small indigenous fish species to recommended intakes of vitamin A and calcium and the perception that mola is good for or protects the eyes have been well documented. An integrated approach was conducted jointly by Bangladeshi and Danish institutions, linking human nutrition and fisheries. Activities included food-consumption surveys, laboratory analyses of commonly consumed fish species, production trials of carp-mola pond polyculture, teaching, training, and dissemination of the results. No decline in carp production and thus in income was found with the inclusion of mola, and increased intake of mola has the potential to combat micronutrient deficiencies. Teaching and training of graduates and field staff have led to increased awareness of the role of small indigenous fish species for good nutrition and resulted in the promotion of carp-mola pond polyculture and research in small indigenous fish species. The decline in accessibility, increase in price, and decrease in intake of small indigenous fish species by the rural poor, as well as the increased intake of silver carp (Hypophthalmichthys molitrix), the most commonly cultured fish species, which is poor in micronutrients and not preferred for consumption, are being addressed, and some measures taken by inland fisheries management have been discussed. The successful linking of human nutrition and fisheries to address micronutrient deficiencies has relevance for other countries with rich fisheries resources, such as Cambodia and countries in the Lake Victoria region of Africa.

Does population density and neighborhood deprivation predict schizophrenia? A nationwide Swedish family-based study of 2.4 million individuals.

PubMed

Sariaslan, Amir; Larsson, Henrik; D'Onofrio, Brian; Långström, Niklas; Fazel, Seena; Lichtenstein, Paul

2015-03-01

People living in densely populated and socially disorganized areas have higher rates of psychiatric morbidity, but the potential causal status of such factors is uncertain. We used nationwide Swedish longitudinal registry data to identify all children born 1967-1989 (n = 2361585), including separate datasets for all cousins (n = 1715059) and siblings (n = 1667894). The nature of the associations between population density and neighborhood deprivation and individual risk for a schizophrenia diagnosis was investigated while adjusting for unobserved familial risk factors (through cousin and sibling comparisons) and then compared with similar associations for depression. We generated familial pedigree structures using the Multi-Generation Registry and identified study participants with schizophrenia and depression using the National Patient Registry. Fixed-effects logistic regression models were used to study within-family estimates. Population density, measured as ln(population size/km(2)), at age 15 predicted subsequent schizophrenia in the population (OR = 1.10; 95% CI: 1.09; 1.11). Unobserved familial risk factors shared by cousins within extended families attenuated the association (1.06; 1.03; 1.10), and the link disappeared entirely within nuclear families (1.02; 0.97; 1.08). Similar results were found for neighborhood deprivation as predictor and for depression as outcome. Sensitivity tests demonstrated that timing and accumulation effects of the exposures (mean scores across birth, ages 1-5, 6-10, and 11-15 years) did not alter the findings. Excess risks of psychiatric morbidity, particularly schizophrenia, in densely populated and socioeconomically deprived Swedish neighborhoods appear, therefore, to result primarily from unobserved familial selection factors. Previous studies may have overemphasized the etiological importance of these environmental factors. © The Author 2014. Published by Oxford University Press on behalf of the Maryland Psychiatric Research Center. All rights reserved. For permissions, please email: journals.permissions@oup.com.

Transformation and motility of human platelets: details of the shape change and release reaction observed by optical and electron microscopy

PubMed Central

1979-01-01

Blood platelets from 10 normal human subjects have been examined with a sensitive differential interference contrast (DIC) microscope. The entire transformation process during adhesion to glass is clearly visible and has been recorded cinematographically, including the disk to sphere change of shape, the formation of sessile protuberances, the extension and retraction of pseudopodia, and the spreading, ruffling, and occasional regression of the hyalomere. The exocytosis of intact dense bodies can be observed either by DIC microscopy, or by epifluorescence microscopy in platelets stained with mepacrine. Details of fluorescent flashes indicate that the dense bodies usually release their contents extracellularly, may do so intracytoplasmically under the influence of strong, short wavelength light on some preparations of mepacrine-stained platelets. The release of one or more dense bodies leaves a crater of variable size on the upper surface of the granulomere. Such craters represent the surface component of the open canalicular system and their formation and disappearance can be directly observed. Because these techniques permit quantitation of several parameters of motility which are not readily observable by other techniques, it is suggested that high extinction DIC microscope examination may become a rapid and useful method of studying congenital and acquired platelet disorders. Many features of platelet transformation have been confirmed and extended by scanning electron micrographs. These can in turn be interpreted by reference to time- lapse films of living platelets. PMID:511936

The Racial/Ethnic Distribution of Heat Risk–Related Land Cover in Relation to Residential Segregation

PubMed Central

Morello-Frosch, Rachel; Cushing, Lara

2013-01-01

Objective: We examined the distribution of heat risk–related land cover (HRRLC) characteristics across racial/ethnic groups and degrees of residential segregation. Methods: Block group–level tree canopy and impervious surface estimates were derived from the 2001 National Land Cover Dataset for densely populated urban areas of the United States and Puerto Rico, and linked to demographic characteristics from the 2000 Census. Racial/ethnic groups in a given block group were considered to live in HRRLC if at least half their population experienced the absence of tree canopy and at least half of the ground was covered by impervious surface (roofs, driveways, sidewalks, roads). Residential segregation was characterized for metropolitan areas in the United States and Puerto Rico using the multigroup dissimilarity index. Results: After adjustment for ecoregion and precipitation, holding segregation level constant, non-Hispanic blacks were 52% more likely (95% CI: 37%, 69%), non-Hispanic Asians 32% more likely (95% CI: 18%, 47%), and Hispanics 21% more likely (95% CI: 8%, 35%) to live in HRRLC conditions compared with non-Hispanic whites. Within each racial/ethnic group, HRRLC conditions increased with increasing degrees of metropolitan area-level segregation. Further adjustment for home ownership and poverty did not substantially alter these results, but adjustment for population density and metropolitan area population attenuated the segregation effects, suggesting a mediating or confounding role. Conclusions: Land cover was associated with segregation within each racial/ethnic group, which may be explained partly by the concentration of racial/ethnic minorities into densely populated neighborhoods within larger, more segregated cities. In anticipation of greater frequency and duration of extreme heat events, climate change adaptation strategies, such as planting trees in urban areas, should explicitly incorporate an environmental justice framework that addresses racial/ethnic disparities in HRRLC. PMID:23694846

Plasmasphere Response: Tutorial and Review of Recent Imaging Results

NASA Astrophysics Data System (ADS)

Goldstein, J.

2006-06-01

The plasmasphere is the cold, dense innermost region of the magnetosphere that is populated by upflow of ionospheric plasma along geomagnetic field lines. Driven directly by dayside magnetopause reconnection, enhanced sunward convection erodes the outer layers of the plasmasphere. Erosion causes the plasmasphere outer boundary, the plasmapause, to move inward on the nightside and outward on the dayside to form plumes of dense plasma extending sunward into the outer magnetosphere. Coupling between the inner magnetosphere and ionosphere can significantly modify the convection field, either enhancing sunward flows near dusk or shielding them on the night side. The plasmaspheric configuration plays a crucial role in the inner magnetosphere; wave-particle interactions inside the plasmasphere can cause scattering and loss of warmer space plasmas such as the ring current and radiation belts.

Net anthropogenic nitrogen accumulation in the Beijing metropolitan region.

PubMed

Han, Yuguo; Li, Xuyong; Nan, Zhe

2011-03-01

A rapid increase in anthropogenic nitrogen inputs has a strong impact on terrestrial and aquatic ecosystems. We have estimated net anthropogenic nitrogen accumulation (NANA) as an index of nitrogen (N) pollution potential in the Beijing metropolitan region, China. Our research provides a basis for understanding the potential impact of anthropogenic N inputs on environmental problems, such as nation-wide water quality degradation under the current rapid urban expansion in modern China. The NANA estimation is based on an inventory of atmospheric N deposition, N fertilizer use, consumption of human food and animal feed, N fixation, and riverine N import and export. We calculated N accumulation values for the years 1991, 1997, 2003, and 2007. The average NANA values for the urban and suburban areas from 1991 to 2007 were 24,038 and 13,090 kg N km(-2) year(-1), respectively. NANA is higher in eastern and southern areas than in northern and western areas, and higher in the urban area than in the suburban area. The overall average NANA in Beijing has a downward trend from 15,187 kg N km(-2) year(-1) in 1991 to 11,606 kg N km(-2) year(-1) in 2007, but is still two to five times as that of developed countries. N input from nitrogenous fertilizer is the largest source of NANA, accounting for 44.4% (6,764 kg N km(-2) year(-1)) of the total N input, followed by atmospheric N deposition and N in human food and animal feed. NANA is closely related to land use, on average 23,140 kg N km(-2) year(-1) in densely populated developed land, 17,904 kg N km(-2) year(-1) in agricultural land, and 10,445 kg N km(-2) year(-1) in forest land. Human population density is the best single predictor of NANA.

Modelling H5N1 in Bangladesh across spatial scales: Model complexity and zoonotic transmission risk.

PubMed

Hill, Edward M; House, Thomas; Dhingra, Madhur S; Kalpravidh, Wantanee; Morzaria, Subhash; Osmani, Muzaffar G; Yamage, Mat; Xiao, Xiangming; Gilbert, Marius; Tildesley, Michael J

2017-09-01

Highly pathogenic avian influenza H5N1 remains a persistent public health threat, capable of causing infection in humans with a high mortality rate while simultaneously negatively impacting the livestock industry. A central question is to determine regions that are likely sources of newly emerging influenza strains with pandemic causing potential. A suitable candidate is Bangladesh, being one of the most densely populated countries in the world and having an intensifying farming system. It is therefore vital to establish the key factors, specific to Bangladesh, that enable both continued transmission within poultry and spillover across the human-animal interface. We apply a modelling framework to H5N1 epidemics in the Dhaka region of Bangladesh, occurring from 2007 onwards, that resulted in large outbreaks in the poultry sector and a limited number of confirmed human cases. This model consisted of separate poultry transmission and zoonotic transmission components. Utilising poultry farm spatial and population information a set of competing nested models of varying complexity were fitted to the observed case data, with parameter inference carried out using Bayesian methodology and goodness-of-fit verified by stochastic simulations. For the poultry transmission component, successfully identifying a model of minimal complexity, which enabled the accurate prediction of the size and spatial distribution of cases in H5N1 outbreaks, was found to be dependent on the administration level being analysed. A consistent outcome of non-optimal reporting of infected premises materialised in each poultry epidemic of interest, though across the outbreaks analysed there were substantial differences in the estimated transmission parameters. The zoonotic transmission component found the main contributor to spillover transmission of H5N1 in Bangladesh was found to differ from one poultry epidemic to another. We conclude by discussing possible explanations for these discrepancies in transmission behaviour between epidemics, such as changes in surveillance sensitivity and biosecurity practices. Copyright © 2017 The Authors. Published by Elsevier B.V. All rights reserved.

Disentangling the effects of climate and people on Sahel vegetation dynamics

NASA Astrophysics Data System (ADS)

Seaquist, J. W.; Hickler, T.; Eklundh, L.; Ardö, J.; Heumann, B. W.

2009-03-01

The Sahel belt of Africa has been the focus of intensive scientific research since the 1960s, spurred on by the chronic vulnerability of its population to recurring drought and the threat of long-term land degradation. But satellite sensors have recently shown that much of the region has experienced significant increases in photosynthetic activity since the early 1980s, thus re-energizing long-standing debates about the role that people play in shaping land surface status, and thus climate at regional scales. In this paper, we test the hypothesis that people have had a measurable impact on vegetation dynamics in the Sahel for the period 1982-2002. We compare potential natural vegetation dynamics predicted by a process-based ecosystem model with satellite-derived greenness observations, and map the agreement between the two across a geographic grid at a spatial resolution of 0.5°. As aggregated data-model agreement is very good, any local differences between the two could be due to human impact. We then relate this agreement metric to state-of-the-art data sets on demographics, pasture, and cropping. Our findings suggest that demographic and agricultural pressures in the Sahel are unable to account for differences between simulated and observed vegetation dynamics, even for the most densely populated areas. But we do identify a weak, positive correlation between data-model agreement and pasture intensity at the Sahel-wide level. This indicates that herding or grazing does not appreciably affect vegetation dynamics in the region. Either people have not had a significant impact on vegetation dynamics in the Sahel or the identification of a human "footprint" is precluded by inconsistent or subtle vegetation response to complex socio-environmental interactions, and/or limitations in the data used for this study. We do not exclude the possibility of a greater human influence on vegetation dynamics over the coming decades with changing land use.

Satellite monitoring of cyanobacterial harmful algal bloom frequency in recreational waters and drinking water sources

EPA Science Inventory

Cyanobacterial harmful algal blooms (cyanoHABs) cause extensive problems in lakes worldwide, including human and ecological health risks, anoxia and fish kills, and taste and odor problems. CyanoHABs are a particular concern because of their dense biomass and the risk of expos...

Identification of genetic markers associated with Gilles de la Tourette syndrome in an Afrikaner population.

PubMed Central

Simonic, I; Gericke, G S; Ott, J; Weber, J L

1998-01-01

Because gene-mapping efforts, using large kindreds and parametric methods of analysis, for the neurologic disorder Tourette syndrome have failed, efforts are being redirected toward association studies in young, genetically isolated populations. The availability of dense marker maps makes it feasible to search for association throughout the entire genome. We report the results of such a genome scan using DNA samples from Tourette patients and unaffected control subjects from the South African Afrikaner population. To optimize mapping efficiency, we chose a two-step strategy. First, we screened pools of DNA samples from both affected and control individuals, using a dense collection of 1,167 short tandem-repeat polymorphisms distributed throughout the genome. Second, we typed those markers displaying evidence of allele frequency-distribution shifts, along with additional tightly linked markers, using DNA from each affected and unaffected individual. To reduce false positives, we tested two independent groups of case and control subjects. Strongest evidence for association (P values 10-2 to 10-5) were obtained for markers within chromosomal regions encompassing D2S1790 near the chromosome 2 centromere, D6S477 on distal 6p, D8S257 on 8q, D11S933 on 11q, D14S1003 on proximal 14q, D20S1085 on distal 20q, and D21S1252 on 21q. PMID:9718333

Identification of genetic markers associated with Gilles de la Tourette syndrome in an Afrikaner population.

PubMed

Simonic, I; Gericke, G S; Ott, J; Weber, J L

1998-09-01

Because gene-mapping efforts, using large kindreds and parametric methods of analysis, for the neurologic disorder Tourette syndrome have failed, efforts are being redirected toward association studies in young, genetically isolated populations. The availability of dense marker maps makes it feasible to search for association throughout the entire genome. We report the results of such a genome scan using DNA samples from Tourette patients and unaffected control subjects from the South African Afrikaner population. To optimize mapping efficiency, we chose a two-step strategy. First, we screened pools of DNA samples from both affected and control individuals, using a dense collection of 1,167 short tandem-repeat polymorphisms distributed throughout the genome. Second, we typed those markers displaying evidence of allele frequency-distribution shifts, along with additional tightly linked markers, using DNA from each affected and unaffected individual. To reduce false positives, we tested two independent groups of case and control subjects. Strongest evidence for association (P values 10-2 to 10-5) were obtained for markers within chromosomal regions encompassing D2S1790 near the chromosome 2 centromere, D6S477 on distal 6p, D8S257 on 8q, D11S933 on 11q, D14S1003 on proximal 14q, D20S1085 on distal 20q, and D21S1252 on 21q.

The Human Blood Metabolome-Transcriptome Interface

PubMed Central

Schramm, Katharina; Adamski, Jerzy; Gieger, Christian; Herder, Christian; Carstensen, Maren; Peters, Annette; Rathmann, Wolfgang; Roden, Michael; Strauch, Konstantin; Suhre, Karsten; Kastenmüller, Gabi; Prokisch, Holger; Theis, Fabian J.

2015-01-01

Biological systems consist of multiple organizational levels all densely interacting with each other to ensure function and flexibility of the system. Simultaneous analysis of cross-sectional multi-omics data from large population studies is a powerful tool to comprehensively characterize the underlying molecular mechanisms on a physiological scale. In this study, we systematically analyzed the relationship between fasting serum metabolomics and whole blood transcriptomics data from 712 individuals of the German KORA F4 cohort. Correlation-based analysis identified 1,109 significant associations between 522 transcripts and 114 metabolites summarized in an integrated network, the ‘human blood metabolome-transcriptome interface’ (BMTI). Bidirectional causality analysis using Mendelian randomization did not yield any statistically significant causal associations between transcripts and metabolites. A knowledge-based interpretation and integration with a genome-scale human metabolic reconstruction revealed systematic signatures of signaling, transport and metabolic processes, i.e. metabolic reactions mainly belonging to lipid, energy and amino acid metabolism. Moreover, the construction of a network based on functional categories illustrated the cross-talk between the biological layers at a pathway level. Using a transcription factor binding site enrichment analysis, this pathway cross-talk was further confirmed at a regulatory level. Finally, we demonstrated how the constructed networks can be used to gain novel insights into molecular mechanisms associated to intermediate clinical traits. Overall, our results demonstrate the utility of a multi-omics integrative approach to understand the molecular mechanisms underlying both normal physiology and disease. PMID:26086077

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

PubMed

D'iachenko, V G

2000-01-01

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

Impact assessment of biomass-based district heating systems in densely populated communities. Part II: Would the replacement of fossil fuels improve ambient air quality and human health?

NASA Astrophysics Data System (ADS)

Petrov, Olga; Bi, Xiaotao; Lau, Anthony

2017-07-01

To determine if replacing fossil fuel combustion with biomass gasification would impact air quality, we evaluated the impact of a small-scale biomass gasification plant (BRDF) at a university campus over 5 scenarios. The overall incremental contribution of fine particles (PM2.5) is found to be at least one order of magnitude lower than the provincial air quality objectives. The maximum PM2.5 emission from the natural gas fueled power house (PH) could adversely add to the already high background concentration levels. Nitrogen dioxide (NO2) emissions from the BRDF with no engineered pollution controls for NOx in place exceeded the provincial objective in all seasons except during summer. The impact score, IS, was the highest for NO2 (677 Disability Adjusted Life Years, DALY) when biomass entirely replaced fossil fuels, and the highest for PM2.5 (64 DALY) and CO (3 DALY) if all energy was produced by natural gas at PH. Complete replacement of fossil fuels by one biomass plant can result in almost 28% higher health impacts (708 DALY) compared to 513 DALY when both the current BRDF and the PH are operational mostly due to uncontrolled NO2 emissions. Observations from this study inform academic community, city planners, policy makers and technology developers on the impacts of community district heating systems and possible mitigation strategies: a) community energy demand could be met either by splitting emissions into more than one source at different locations and different fuel types or by a single source with the least-impact-based location selection criteria with biomass as a fuel; b) advanced high-efficiency pollution control devices are essential to lower emissions for emission sources located in a densely populated community; c) a spatial and temporal impact assessment should be performed in developing bioenergy-based district heating systems, in which the capital and operational costs should be balanced with not only the benefit to greenhouse gas emission reduction but also the health impact to the local community.

Extended-spectrum β-lactamase- and pAmpC-producing Enterobacteriaceae among the general population in a livestock-dense area.

PubMed

Wielders, C C H; van Hoek, A H A M; Hengeveld, P D; Veenman, C; Dierikx, C M; Zomer, T P; Smit, L A M; van der Hoek, W; Heederik, D J; de Greeff, S C; Maassen, C B M; van Duijkeren, E

2017-02-01

In the Netherlands there is an ongoing debate regarding environmental health risks of livestock farming for neighbouring residents. This explorative study aims to determine the prevalence of carriage of extended-spectrum β-lactamase and/or plasmid-mediated AmpC-producing Enterobacteriaceae (ESBL/pAmpC-E) in the general population living in a livestock-dense area, and to study associations between determinants, including exposure through contact with animals and the environment, and human carriage of ESBL/pAmpC-E. A cross-sectional study was performed among 2432 adults (aged 20-72 years) in 12 temporary research centres in the south of the Netherlands, consisting of a questionnaire and analysis of a faecal sample to assess carriage of ESBL/pAmpC-E. Risk factors were analysed using logistic regression. The prevalence for carriage of ESBL/pAmpC-E was 4.5% (109/2432; 95% CI 3.7-5.4) ranging from 1.4% to 10.9% among the research centres. ESBL/pAmpC resistance genes were detected in Escherichia coli and Klebsiella pneumoniae isolates obtained from these 109 persons and the most common ESBL-resistance genes were bla CTX-M-15 , bla CTX-M-14/17 and bla CTX-M-1 , originating from 76 participants. Travel in the previous 12 months to Africa, Asia or Latin America (OR 2.82; 95% CI 1.71-4.63), having kept cows for a hobby in the previous 5 years (OR 3.77; 95% CI 1.22-11.64), usage of proton-pump inhibitors (OR 1.84; 95% CI 1.05-3.23), and living within 1000 m of a mink farm (OR 2.26; 95% CI 1.28-3.98) were identified as risk factors. Exposure to poultry was not identified as a risk factor. Overall, living in close proximity to livestock animals and farms does not seem to be a risk factor for carriage of ESBL/pAmpC-E. Copyright © 2016 European Society of Clinical Microbiology and Infectious Diseases. Published by Elsevier Ltd. All rights reserved.

Tectonically Undulating Terrestrial Geospheres and Concordant Development of Two Distinct Somatic Types of Man

NASA Astrophysics Data System (ADS)

Kochemasov, G. G.

The human organisms in microgravity conditions loss Ca or become less dense. But variously dense men also develop on Earth due to varying tectonics. As any celestial body, Earth is not a billiard-ball but is complexly warped by a number of standing waves imprinted in the geoid shape. The fundamental wave (long 2π R, R- planet radius) makes tectonic dichotomy (an opposition of the eastern and western oceanic hemispheres), the first overtone (π R) makes sectoring: on the continental eastern hemisphere, for example, around the Pamirs-Hindukush converge 4 sectors. They are 2 opposed differently uplifted (African ++, Asian +) separated by 2 opposed differently subsided (Eurasian -, Indoceanic - -). In rotating Earth the alternating uplifts (++, +) and subsidences (- -, -) require materials of different densities: less dense for uplifts and denser for subsidences. This requirement concerns all geospheres including anthroposphere. The long development of Homo sapiens adapting to graviconditions of uplifting and subsiding blocks produced two distinct somatic types of man: long and narrow (slim) leptosomes and short and broad eirisomes. As shows F. Weidenreich [1], this fundamental division appeared very early in the human history and is observed in all great human races and even in apes. A block uplifting (an increase of the planetary radius) requires diminishing density. This is achieved by distributing the man's weight by the longer stature. Thus appears long and slim leptosome. On the contrary, a block subsidence (diminishing radius) requires increasing density: man is shorter and broader (eirisome). A long existence on intensively moving (up or down) blocks makes these somatic types characteristic of races. Thus, many African tribes developing on intensively moving up continent (more than one kilometer in a few mln. y. ) are leptosomatic; on the contrary, Indians of subsiding western hemisphere are typically eirisomatic with high Rohrer's index; Polynesians of Pacific are high but corpulent, the Rohrer' index is also high. Short in time cosmic experiments (abrupt uplifting) with a sharp drop in gravity produce noticeable effect of Ca leaching out of organism making it less dense. Sure, changing gravity influences not only bones but also flesh, blood, hairs and eventually genes. The frequencies of genetic markers of Rh-system in blood of inhabitants of 4 variously leveled sectors and subsided western hemisphere are clearly different. References: [1] F. Weidenreich. Rasse und Körperbau (in Russian translation, State Publishing House, Moscow-Leningrad, 1929, 271 pp.).

Synchronized Oviposition Triggered by Migratory Flight Intensifies Larval Outbreaks of Beet Webworm

PubMed Central

Cheng, Yun Xia; Luo, Li Zhi; Jiang, Xing Fu; Sappington, Thomas W.

2012-01-01

Identifying the reproductive consequences of insect migration is critical to understanding its ecological and evolutionary significance. However, many empirical studies are seemingly contradictory, making recognition of unifying themes elusive and controversial. The beet webworm, Loxostege sticticalis L. is a long-range migratory pest of many crops in the northern temperate zone from 36°N to 55°N, with larval populations often exploding in regions receiving immigrants. In laboratory experiments, we examined (i) the reproductive costs of migratory flight by tethered flight, and (ii) the reproductive traits contributing to larval outbreaks of immigrant populations. Our results suggest that the beet webworm does not initiate migratory flight until the 2nd or 3rd night after emergence. Preoviposition period, lifetime fecundity, mating capacity, and egg hatch rate for adults that experienced prolonged flight after the 2nd night did not differ significantly from unflown moths, suggesting these traits are irrelevant to the severity of beet webworm outbreaks after migration. However, the period of first oviposition, a novel parameter developed in this paper measuring synchrony of first egg-laying by cohorts of post-migratory females, for moths flown on d 3 and 5 of adulthood was shorter than that of unflown moths, indicating a tightened time-window for onset of oviposition after migration. The resulting synchrony of egg-laying will serve to increase egg and subsequent larval densities. A dense population offers potential selective advantages to the individual larvae comprising it, whereas the effect from the human standpoint is intensification of damage by an outbreak population. The strategy of synchronized oviposition may be common in other migratory insect pests, such as locust and armyworm species, and warrants further study. PMID:22347494

Module discovery by exhaustive search for densely connected, co-expressed regions in biomolecular interaction networks.

PubMed

Colak, Recep; Moser, Flavia; Chu, Jeffrey Shih-Chieh; Schönhuth, Alexander; Chen, Nansheng; Ester, Martin

2010-10-25

Computational prediction of functionally related groups of genes (functional modules) from large-scale data is an important issue in computational biology. Gene expression experiments and interaction networks are well studied large-scale data sources, available for many not yet exhaustively annotated organisms. It has been well established, when analyzing these two data sources jointly, modules are often reflected by highly interconnected (dense) regions in the interaction networks whose participating genes are co-expressed. However, the tractability of the problem had remained unclear and methods by which to exhaustively search for such constellations had not been presented. We provide an algorithmic framework, referred to as Densely Connected Biclustering (DECOB), by which the aforementioned search problem becomes tractable. To benchmark the predictive power inherent to the approach, we computed all co-expressed, dense regions in physical protein and genetic interaction networks from human and yeast. An automatized filtering procedure reduces our output which results in smaller collections of modules, comparable to state-of-the-art approaches. Our results performed favorably in a fair benchmarking competition which adheres to standard criteria. We demonstrate the usefulness of an exhaustive module search, by using the unreduced output to more quickly perform GO term related function prediction tasks. We point out the advantages of our exhaustive output by predicting functional relationships using two examples. We demonstrate that the computation of all densely connected and co-expressed regions in interaction networks is an approach to module discovery of considerable value. Beyond confirming the well settled hypothesis that such co-expressed, densely connected interaction network regions reflect functional modules, we open up novel computational ways to comprehensively analyze the modular organization of an organism based on prevalent and largely available large-scale datasets. Software and data sets are available at http://www.sfu.ca/~ester/software/DECOB.zip.

Pyrodiversity and the anthropocene: the role of fire in the broad spectrum revolution.

PubMed

Bird, Douglas W; Bliege Bird, Rebecca; Codding, Brian F

2016-05-06

The Anthropocene colloquially refers to a global regime of human-caused environmental modification of earth systems associated with profound changes in patterns of human mobility, as well as settlement and resource use compared with prior eras. Some have argued that the processes generating the Anthropocene are mainly associated with population growth and technological innovation, and thus began only in the late Holocene under conditions of dense sedentism and industrial agriculture.(1) However, it now seems clear that the roots of the Anthropocene lie in complex processes of intensification that significantly predate transitions to agriculture.(2,3) What intensification is remains less clear. For some it is increasing economic productivity that increases carrying capacity, the drivers of which may be too diverse and too local to generalize.(4,5) For others using Boserup's ideas about agrarian intensification, increasing density in hunter-gatherer populations can produce declines in subsistence efficiency that increase incentives for investing labor to boost yield per unit area, which then elevates Malthusian limits on carrying capacity.(6-8) As Morgan(9) demonstrates in a comprehensive review, the legacy of such Boserupian intensification is alive, well, and controversial in hunter-gatherer archeology. This is a result of its potential for illuminating processes involved in transformations of forager socio-political and economic systems, including those dominated by harvesting more immediate-return resources and high residential mobility as well as those characterized by more delayed-return material economies with reduced residential mobility, a broader spectrum of resources, degrees of storage, and greater social stratification. Here we detail hypotheses about the processes involved in such transitions and explore the way that anthropogenic disturbance of ecosystems, especially the use of landscape fire, could be fundamentally entangled with many broad-spectrum revolutions associated with intensified foraging systems. © 2016 Wiley Periodicals, Inc.

Disentangling the effects of climate and people on Sahel vegetation dynamics

NASA Astrophysics Data System (ADS)

Seaquist, J. W.; Hickler, T.; Eklundh, L.; Ardö, J.; Heumann, B. W.

2008-08-01

The Sahel belt of Africa has been the focus of intensive scientific research since the 1960s, spurred on by the chronic vulnerability of its population to recurring drought and the threat of long-term land degradation. But satellite sensors have recently shown that much of the region has experienced significant increases in photosynthetic activity since the early 1980s, thus re-energizing long-standing debates about the role that people play in shaping land surface status, and thus climate at regional scales. In this paper, we test the hypothesis that people have had a measurable impact on vegetation dynamics in the Sahel for the period 1982 2002. We compare potential natural vegetation dynamics predicted by a process-based ecosystem model with satellite-derived greenness observations, and map the agreement between the two across a geographic grid at a spatial resolution of 0.5°. As aggregated data-model agreement is very good, any local differences between the two could be due to human impact. We then relate this agreement metric to state-of-the-art data sets on demographics, pasture, and cropping. Our findings suggest that demographic and agricultural pressures in the Sahel are unable to account for differences between simulated and observed vegetation dynamics, even for the most densely populated areas. But we do identify a weak, positive correlation between data-model agreement and pasture intensity at the Sahel-wide level. This indicates that herding or grazing does not appreciably affect vegetation dynamics in the region. Either people have not had a significant impact on vegetation dynamics in the Sahel or the identification of a human "footprint" is precluded by inconsistent or subtle vegetation response to complex socio-environmental interactions, and/or limitations in the data used for this study.

Probing Prokaryotic Social Behaviors with Bacterial “Lobster Traps”

PubMed Central

Connell, Jodi L.; Wessel, Aimee K.; Parsek, Matthew R.; Ellington, Andrew D.; Whiteley, Marvin; Shear, Jason B.

2010-01-01

Bacteria are social organisms that display distinct behaviors/phenotypes when present in groups. These behaviors include the abilities to construct antibiotic-resistant sessile biofilm communities and to communicate with small signaling molecules (quorum sensing [QS]). Our understanding of biofilms and QS arises primarily from in vitro studies of bacterial communities containing large numbers of cells, often greater than 108 bacteria; however, in nature, bacteria often reside in dense clusters (aggregates) consisting of significantly fewer cells. Indeed, bacterial clusters containing 101 to 105 cells are important for transmission of many bacterial pathogens. Here, we describe a versatile strategy for conducting mechanistic studies to interrogate the molecular processes controlling antibiotic resistance and QS-mediated virulence factor production in high-density bacterial clusters. This strategy involves enclosing a single bacterium within three-dimensional picoliter-scale microcavities (referred to as bacterial “lobster traps”) defined by walls that are permeable to nutrients, waste products, and other bioactive small molecules. Within these traps, bacteria divide normally into extremely dense (1012 cells/ml) clonal populations with final population sizes similar to that observed in naturally occurring bacterial clusters. Using these traps, we provide strong evidence that within low-cell-number/high-density bacterial clusters, QS is modulated not only by bacterial density but also by population size and flow rate of the surrounding medium. We also demonstrate that antibiotic resistance develops as cell density increases, with as few as ~150 confined bacteria exhibiting an antibiotic-resistant phenotype similar to biofilm bacteria. Together, these findings provide key insights into clinically relevant phenotypes in low-cell-number/high-density bacterial populations. PMID:21060734