Does source population size affect performance in new environments?
Yates, Matthew C; Fraser, Dylan J
2014-01-01
Small populations are predicted to perform poorly relative to large populations when experiencing environmental change. To explore this prediction in nature, data from reciprocal transplant, common garden, and translocation studies were compared meta-analytically. We contrasted changes in performance resulting from transplantation to new environments among individuals originating from different sized source populations from plants and salmonids. We then evaluated the effect of source population size on performance in natural common garden environments and the relationship between population size and habitat quality. In ‘home-away’ contrasts, large populations exhibited reduced performance in new environments. In common gardens, the effect of source population size on performance was inconsistent across life-history stages (LHS) and environments. When transplanted to the same set of new environments, small populations either performed equally well or better than large populations, depending on life stage. Conversely, large populations outperformed small populations within native environments, but only at later life stages. Population size was not associated with habitat quality. Several factors might explain the negative association between source population size and performance in new environments: (i) stronger local adaptation in large populations and antagonistic pleiotropy, (ii) the maintenance of genetic variation in small populations, and (iii) potential environmental differences between large and small populations. PMID:25469166
Using temporal sampling to improve attribution of source populations for invasive species.
Goldstien, Sharyn J; Inglis, Graeme J; Schiel, David R; Gemmell, Neil J
2013-01-01
Numerous studies have applied genetic tools to the identification of source populations and transport pathways for invasive species. However, there are many gaps in the knowledge obtained from such studies because comprehensive and meaningful spatial sampling to meet these goals is difficult to achieve. Sampling populations as they arrive at the border should fill the gaps in source population identification, but such an advance has not yet been achieved with genetic data. Here we use previously acquired genetic data to assign new incursions as they invade populations within New Zealand ports and marinas. We also investigated allelelic frequency change in these recently established populations over a two-year period, and assessed the effect of temporal genetic sampling on our ability to assign new incursions to their population of source. We observed shifts in the allele frequencies among populations, as well as the complete loss of some alleles and the addition of alleles novel to New Zealand, within these recently established populations. There was no significant level of genetic differentiation observed in our samples between years, and the use of these temporal data did alter the assignment probability of new incursions. Our study further suggests that new incursions can add genetic variation to the population in a single introduction event as the founders themselves are often more genetically diverse than theory initially predicted.
The role of local populations within a landscape context: Defining and classifying sources and sinks
Runge, J.P.; Runge, M.C.; Nichols, J.D.
2006-01-01
The interaction of local populations has been the focus of an increasing number of studies in the past 30 years. The study of source-sink dynamics has especially generated much interest. Many of the criteria used to distinguish sources and sinks incorporate the process of apparent survival (i.e., the combined probability of true survival and site fidelity) but not emigration. These criteria implicitly treat emigration as mortality, thus biasing the classification of sources and sinks in a manner that could lead to flawed habitat management. Some of the same criteria require rather restrictive assumptions about population equilibrium that, when violated, can also generate misleading inference. Here, we expand on a criterion (denoted ?contribution? or Cr) that incorporates successful emigration in differentiating sources and sinks and that makes no restrictive assumptions about dispersal or equilibrium processes in populations of interest. The metric Cr is rooted in the theory of matrix population models, yet it also contains clearly specified parameters that have been estimated in previous empirical research. We suggest that estimates of emigration are important for delineating sources and sinks and, more generally, for evaluating how local populations interact to generate overall system dynamics. This suggestion has direct implications for issues such as species conservation and habitat management.
Characterization of the near-source population around five ...
Many ports are currently preparing for increased freight traffic, which may result in elevated local air pollution in areas near the port and freight transportation corridors. In this study, a geographical information system (GIS) analysis of areas surrounding five ports – Port of New York and New Jersey, Port of Virginia, Port of Savannah, Port of Miami, and Port of Houston – was conducted to characterize the population that might be affected by air emissions from the freight transportation network and to determine which sources had the potential to affect the most people. Defining “near-source” populations as living within 300 m of the freight transportation network, namely the port and associated truck routes, railroads, and intermodal facilities (e. g. rail yards and warehouses); near-source populations ranged from 37,000 to over a million within 10 km of a port. At the ports considered, the population living within 300 m of the port boundary constituted <10 % of the total near-source population. Sensitive population exposure was also indicated, such as the 81 day care centers and K-12 schools in near-source environments within 2 km of the Port of New York and New Jersey. Minority groups constituted 55 % to 85 % of the near-source populations in the five port areas. For four of the five ports, the mean and median income of the near-source population was lower and the minority percentage was higher than the population living adjacent to the near-sou
Probing the X-Ray Binary Populations of the Ring Galaxy NGC 1291
NASA Technical Reports Server (NTRS)
Luo, B.; Fabbiano, G.; Fragos, T.; Kim, D. W.; Belczynski, K.; Brassington, N. J.; Pellegrini, S.; Tzanavaris, P.; Wang, J.; Zezas, A.
2012-01-01
We present Chandra studies of the X-ray binary (XRB) populations in the bulge and ring regions of the ring galaxy NGC 1291. We detect 169 X-ray point sources in the galaxy, 75 in the bulge and 71 in the ring, utilizing the four available Chandra observations totaling an effective exposure of 179 ks. We report photometric properties of these sources in a point-source catalog. There are approx. 40% of the bulge sources and approx. 25% of the ring sources showing > 3(sigma) long-term variability in their X-ray count rate. The X-ray colors suggest that a significant fraction of the bulge (approx. 75%) and ring (approx. 65%) sources are likely low-mass X-ray binaries (LMXBs). The spectra of the nuclear source indicate that it is a low-luminosity AGN with moderate obscuration; spectral variability is observed between individual observations. We construct 0.3-8.0 keV X-ray luminosity functions (XLFs) for the bulge and ring XRB populations, taking into account the detection incompleteness and background AGN contamination. We reach 90% completeness limits of approx.1.5 x 10(exp 37) and approx. 2.2 x 10(exp 37) erg/s for the bulge and ring populations, respectively. Both XLFs can be fit with a broken power-law model, and the shapes are consistent with those expected for populations dominated by LMXBs. We perform detailed population synthesis modeling of the XRB populations in NGC 1291 , which suggests that the observed combined XLF is dominated by aD old LMXB population. We compare the bulge and ring XRB populations, and argue that the ring XRBs are associated with a younger stellar population than the bulge sources, based on the relative over-density of X-ray sources in the ring, the generally harder X-ray color of the ring sources, the overabundance of luminous sources in the combined XLF, and the flatter shape of the ring XLF.
Patterns of Genetic Variation among Populations of the Asian Longhorned Beetle in China and Korea
USDA-ARS?s Scientific Manuscript database
Central to the study of invasive species is identifying source populations in their native ranges. Source populations of invasive species can provide important information about species life cycles, host use and species-specific predators and parasites which could be deployed in a pest control prog...
Genetic consequences of trumpeter swan (Cygnus buccinator) reintroductions
Ransler, F.A.; Quinn, T.W.; Oyler-McCance, S.J.
2011-01-01
Relocation programs are often initiated to restore threatened species to previously occupied portions of their range. A primary challenge of restoration efforts is to translocate individuals in a way that prevents loss of genetic diversity and decreases differentiation relative to source populations-a challenge that becomes increasingly difficult when remnant populations of the species are already genetically depauperate. Trumpeter swans were previously extirpated in the entire eastern half of their range. Physical translocations of birds over the last 70 years have restored the species to portions of its historical range. Despite the long history of management, there has been little monitoring of the genetic outcomes of these restoration attempts. We assessed the consequences of this reintroduction program by comparing patterns of genetic variation at 17 microsatellite loci across four restoration flocks (three wild-released, one captive) and their source populations. We found that a wild-released population established from a single source displayed a trend toward reduced genetic diversity relative to and significant genetic differentiation from its source population, though small founder population effects may also explain this pattern. Wild-released flocks restored from multiple populations maintained source levels of genetic variation and lacked significant differentiation from at least one of their sources. Further, the flock originating from a single source revealed significantly lower levels of genetic variation than those established from multiple sources. The distribution of genetic variation in the captive flock was similar to its source. While the case of trumpeter swans provides evidence that restorations from multiple versus single source populations may better preserve natural levels of genetic diversity, more studies are needed to understand the general applicability of this management strategy. ?? 2010 Springer Science+Business Media B.V. (outside the USA).
ERIC Educational Resources Information Center
Gbadamosi, Belau Olatunde
2013-01-01
The paper examines demographic information sources and utilization as determinants of educational policy making in South West Nigeria. Using validated and structured questionnaire, the study population of 398 officers in the ministries of education in the affected states were enumerated. The study establishes population census, vital registration,…
Li, Wenhong; Jin, Daochao; Shi, Caihua; Li, Fengliang
2017-05-16
Gut bacteria play a significant role in host insect. This study evaluated detail difference of midgut bacteria in deltamethrin-resistant, deltamethrin-susceptible and field-caught populations of diamondback moth, and studied phenomics of the predominant midgut bacterium Enterococcus mundtii. Cultivable bacteria revealed that E. mundtii and Carnobacterium maltaromaticum dominated the bacterial populations from deltamethrin-resistant and deltamethrin-susceptible larval midguts, whereas E. mundtii was predominant in field-caught population. Illumina sequencing analysis indicated that 97% of the midgut bacteria were from the phyla Firmicutes, Proteobacteria and Cyanobacteria. Both resistant and susceptible populations had more Enterococcus and Carnobacterium. Enterococcus, Carnobacterium, Bacillus, and Pseudomonas were predominant in the field-caught population. A phenomics analysis revealed that E. mundtii was able to metabolize 25.26% of the tested carbon sources, 100% of the nitrogen sources, 100% of the phosphorus sources and 97.14% of the sulfur sources, had a wide range of osmolytes and pH conditions, and showed active deaminase activity but no decarboxylase activity. This is the first report regarding different populations of DBM midgut bacteria analyzed using both high-throughput DNA sequencing and cultivation methods, and also first report concerning the phenomics of E. mundtii. The phenomics of E. mundtii provide a basis for the future study of gut bacteria functions.
Survival of mountain quail translocated from two distinct source populations
Troy, Ronald J.; Coates, Peter S.; Connelly, John W.; Gillette, Gifford; Delehanty, David J.
2013-01-01
Translocation of mountain quail (Oreortyx pictus) to restore viable populations to their former range has become a common practice. Because differences in post-release vital rates between animals from multiple source populations has not been well studied, wildlife and land managers may arbitrarily choose the source population or base the source population on immediate availability when planning translocation projects. Similarly, an understanding of the optimal proportion of individuals from different age and sex classes for translocation would benefit translocation planning. During 2006 and 2007, we captured and translocated 125 mountain quail from 2 ecologically distinct areas: 38 from southern California and 87 from southwestern Oregon. We released mountain quail in the Bennett Hills of south-central Idaho. We radio-marked and monitored a subsample of 58 quail and used them for a 2-part survival analysis. Cumulative survival probability was 0.23 ± 0.05 (SE) at 150 days post-release. We first examined an a priori hypothesis (model) that survival varied between the 2 distinct source populations. We found that source population did not explain variation in survival. This result suggests that wildlife managers have flexibility in selecting source populations for mountain quail translocation efforts. In a post hoc examination, we pooled the quail across source populations and evaluated differences in survival probabilities between sex and age classes. The most parsimonious model indicated that adult male survival was substantially less than survival rates of other mountain quail age and sex classes (i.e., interaction between sex and age). This result suggests that translocation success could benefit by translocating yearling males rather than adult males, perhaps because adult male breeding behavior results in vulnerability to predators
Combining multiple sources of data to inform conservation of Lesser Prairie-Chicken populations
Ross, Beth; Haukos, David A.; Hagen, Christian A.; Pitman, James
2018-01-01
Conservation of small populations is often based on limited data from spatially and temporally restricted studies, resulting in management actions based on an incomplete assessment of the population drivers. If fluctuations in abundance are related to changes in weather, proper management is especially important, because extreme weather events could disproportionately affect population abundance. Conservation assessments, especially for vulnerable populations, are aided by a knowledge of how extreme events influence population status and trends. Although important for conservation efforts, data may be limited for small or vulnerable populations. Integrated population models maximize information from various sources of data to yield population estimates that fully incorporate uncertainty from multiple data sources while allowing for the explicit incorporation of environmental covariates of interest. Our goal was to assess the relative influence of population drivers for the Lesser Prairie-Chicken (Tympanuchus pallidicinctus) in the core of its range, western and southern Kansas, USA. We used data from roadside lek count surveys, nest monitoring surveys, and survival data from telemetry monitoring combined with climate (Palmer drought severity index) data in an integrated population model. Our results indicate that variability in population growth rate was most influenced by variability in juvenile survival. The Palmer drought severity index had no measurable direct effects on adult survival or mean number of offspring per female; however, there were declines in population growth rate following severe drought. Because declines in population growth rate occurred at a broad spatial scale, declines in response to drought were likely due to decreases in chick and juvenile survival rather than emigration outside of the study area. Overall, our model highlights the importance of accounting for environmental and demographic sources of variability, and provides a thorough method for simultaneously evaluating population demography in response to long-term climate effects.
Ford, Lorelei; Bharadwaj, Lalita; McLeod, Lianne; Waldner, Cheryl
2017-07-28
Safe drinking water is a global challenge for rural populations dependent on unregulated water. A scoping review of research on human health risk assessments (HHRA) applied to this vulnerable population may be used to improve assessments applied by government and researchers. This review aims to summarize and describe the characteristics of HHRA methods, publications, and current literature gaps of HHRA studies on rural populations dependent on unregulated or unspecified drinking water. Peer-reviewed literature was systematically searched (January 2000 to May 2014) and identified at least one drinking water source as unregulated (21%) or unspecified (79%) in 100 studies. Only 7% of reviewed studies identified a rural community dependent on unregulated drinking water. Source water and hazards most frequently cited included groundwater (67%) and chemical water hazards (82%). Most HHRAs (86%) applied deterministic methods with 14% reporting probabilistic and stochastic methods. Publications increased over time with 57% set in Asia, and 47% of studies identified at least one literature gap in the areas of research, risk management, and community exposure. HHRAs applied to rural populations dependent on unregulated water are poorly represented in the literature even though almost half of the global population is rural.
Ford, Lorelei; Bharadwaj, Lalita; McLeod, Lianne; Waldner, Cheryl
2017-01-01
Safe drinking water is a global challenge for rural populations dependent on unregulated water. A scoping review of research on human health risk assessments (HHRA) applied to this vulnerable population may be used to improve assessments applied by government and researchers. This review aims to summarize and describe the characteristics of HHRA methods, publications, and current literature gaps of HHRA studies on rural populations dependent on unregulated or unspecified drinking water. Peer-reviewed literature was systematically searched (January 2000 to May 2014) and identified at least one drinking water source as unregulated (21%) or unspecified (79%) in 100 studies. Only 7% of reviewed studies identified a rural community dependent on unregulated drinking water. Source water and hazards most frequently cited included groundwater (67%) and chemical water hazards (82%). Most HHRAs (86%) applied deterministic methods with 14% reporting probabilistic and stochastic methods. Publications increased over time with 57% set in Asia, and 47% of studies identified at least one literature gap in the areas of research, risk management, and community exposure. HHRAs applied to rural populations dependent on unregulated water are poorly represented in the literature even though almost half of the global population is rural. PMID:28788087
The derived population of luminous supersoft X-ray sources
NASA Technical Reports Server (NTRS)
Di Stefano, R.STEFANO; Rappaport, S.
1994-01-01
The existence of a new class of astrophysical object, luminous supersoft X-ray sources, has been established through ROSAT satellite observations and analysis during the past approximately 3 yr. Because most of the radiation emitted by supersoft sources spans a range of wavelengths readily absorbed by interstellar gas, a substantial fraction of these sources may not be detectable with present satellite instrumentation. It is therefore important to derive a reliable estimate of the underlying population, based on the approximately 30 sources that have been observed to date. The work reported here combines the observational results with a theoretical analysis, to obtain an estimate of the total number of sources likely to be present in M31, the Magellanic Clouds, and in our own Galaxy. We find that in M31, where approximately 15 supersoft sources have been identified and roughly an equal number of sources are being investigated as supersoft candidates, there are likely to be approximately 2500 active supersoft sources at the present time. In our own Galaxy, where about four supersoft sources have been detected in the Galactic plane, there are likely to be approximately 1000 active sources. Similarly, with about six and about four (nonforeground) sources observed in the Large (LMC) and Small Magellanic Clouds (SMC), respectively, there should be approximately 30 supersoft sources in the LMC, and approximately 20 in the SMC. The likely uncertainties in the numbers quoted above, and the properties of observable sources relative to those of the total underlying population, are also derived in detail. These results can be scaled to estimate the numbers of supersoft sources likely to be present in other galaxies. The results reported here on the underlying population of supersoft X-ray sources are in good agreement with the results of a prior population synthesis study of the white dwarf accretor model for luminous supersoft X-ray sources. It should be emphasized, however, that the questions asked in these two investigations are distinct, that the approaches taken to answer these questions are largely independent and that the findings of these two studies could in principle have been quite different.
2018-01-01
ABSTRACT Population at risk of crime varies due to the characteristics of a population as well as the crime generator and attractor places where crime is located. This establishes different crime opportunities for different crimes. However, there are very few efforts of modeling structures that derive spatiotemporal population models to allow accurate assessment of population exposure to crime. This study develops population models to depict the spatial distribution of people who have a heightened crime risk for burglaries and robberies. The data used in the study include: Census data as source data for the existing population, Twitter geo-located data, and locations of schools as ancillary data to redistribute the source data more accurately in the space, and finally gridded population and crime data to evaluate the derived population models. To create the models, a density-weighted areal interpolation technique was used that disaggregates the source data in smaller spatial units considering the spatial distribution of the ancillary data. The models were evaluated with validation data that assess the interpolation error and spatial statistics that examine their relationship with the crime types. Our approach derived population models of a finer resolution that can assist in more precise spatial crime analyses and also provide accurate information about crime rates to the public. PMID:29887766
NuSTAR view of the central region of M31
NASA Astrophysics Data System (ADS)
Stiele, H.; Kong, A. K. H.
2018-04-01
Our neighbouring large spiral galaxy, the Andromeda galaxy (M31 or NGC 224), is an ideal target to study the X-ray source population of a nearby galaxy. NuSTAR observed the central region of M31 in 2015 and allows studying the population of X-ray point sources at energies higher than 10 keV. Based on the source catalogue of the large XMM-Newton survey of M31, we identified counterparts to the XMM-Newton sources in the NuSTAR data. The NuSTAR data only contain sources of a brightness comparable (or even brighter) than the selected sources that have been detected in XMM-Newton data. We investigate hardness ratios, spectra, and long-term light curves of individual sources obtained from NuSTAR data. Based on our spectral studies, we suggest four sources as possible X-ray binary candidates. The long-term light curves of seven sources that have been observed more than once show low (but significant) variability.
Spatial variation in anthropogenic mortality induces a source-sink system in a hunted mesopredator.
Minnie, Liaan; Zalewski, Andrzej; Zalewska, Hanna; Kerley, Graham I H
2018-04-01
Lethal carnivore management is a prevailing strategy to reduce livestock predation. Intensity of lethal management varies according to land-use, where carnivores are more intensively hunted on farms relative to reserves. Variations in hunting intensity may result in the formation of a source-sink system where carnivores disperse from high-density to low-density areas. Few studies quantify dispersal between supposed sources and sinks-a fundamental requirement for source-sink systems. We used the black-backed jackal (Canis mesomelas) as a model to determine if heterogeneous anthropogenic mortality induces a source-sink system. We analysed 12 microsatellite loci from 554 individuals from lightly hunted and previously unhunted reserves, as well as heavily hunted livestock- and game farms. Bayesian genotype assignment showed that jackal populations displayed a hierarchical population structure. We identified two genetically distinct populations at the regional level and nine distinct subpopulations at the local level, with each cluster corresponding to distinct land-use types separated by various dispersal barriers. Migration, estimated using Bayesian multilocus genotyping, between reserves and farms was asymmetric and heterogeneous anthropogenic mortality induced source-sink dynamics via compensatory immigration. Additionally some heavily hunted populations also acted as source populations, exporting individuals to other heavily hunted populations. This indicates that heterogeneous anthropogenic mortality results in the formation of a complex series of interconnected sources and sinks. Thus, lethal management of mesopredators may not be an effective long-term strategy in reducing livestock predation, as dispersal and, more importantly, compensatory immigration may continue to affect population reduction efforts as long as dispersal from other areas persists.
Nagano, Yasuharu; Yako-Suketomo, Hiroko; Natsui, Hiroaki
2018-01-01
Raising awareness on a disorder is important for its prevention and for promoting public health. However, for sports injuries like the anterior cruciate ligament (ACL) injury no studies have investigated the awareness on risk factors for injury and possible preventative measures in the general population. The sources of information among the population are also unclear. The purpose of the present study was to identify these aspects of public awareness about the ACL injury. A questionnaire was randomly distributed among the general population registered with a web based questionnaire supplier, to recruit 900 participants who were aware about the ACL injury. The questionnaire consisted of two parts: Question 1 asked them about their sources of information regarding the ACL injury; Question 2 asked them about the risk factors for ACL injury. Multivariate logistic regression was used to determine the information sources that provide a good understanding of the risk factors. The leading source of information for ACL injury was television (57.0%). However, the results of logistic regression analysis revealed that television was not an effective medium to create awareness about the risk factors, among the general population. Instead "Lecture by a coach", "Classroom session on Health", and "Newspaper" were significantly more effective in creating a good awareness of the risk factors (p < 0.001).
Multiscale Spatial Modeling of Human Exposure from Local Sources to Global Intake.
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.
Lamendella, Regina; Li, Kent C.; Oerther, Daniel
2013-01-01
Several swine-specific microbial source tracking methods are based on PCR assays targeting Bacteroidales 16S rRNA gene sequences. The limited application of these assays can be explained by the poor understanding of their molecular diversity in fecal sources and environmental waters. In order to address this, we studied the diversity of 9,340 partial (>600 bp in length) Bacteroidales 16S rRNA gene sequences from 13 fecal sources and nine feces-contaminated watersheds. The compositions of major Bacteroidales populations were analyzed to determine which host and environmental sequences were contributing to each group. This information allowed us to identify populations which were both exclusive to swine fecal sources and detected in swine-contaminated waters. Phylogenetic and diversity analyses revealed that some markers previously believed to be highly specific to swine populations are shared by multiple hosts, potentially explaining the cross-amplification signals obtained with nontargeted hosts. These data suggest that while many Bacteroidales populations are cosmopolitan, others exhibit a preferential host distribution and may be able to survive different environmental conditions. This study further demonstrates the importance of elucidating the diversity patterns of targeted bacterial groups to develop more inclusive fecal source tracking applications. PMID:23160126
Evidence of local adaptation in westslope cutthroat trout
Drinan, Daniel P.; Zale, Alexander V.; Webb, Molly A.H.; Taper, Mark L.; Shepard, Bradley B.; Kalinowski, Steven T.
2012-01-01
An understanding of the process of local adaptation would allow managers to better protect and conserve species. Many salmonids are in need of such efforts, and because they often persist in differing, isolated environments, they are useful organisms for studying local adaptation. In addition, the temperature sensitivity of salmonids provides a likely target for natural selection. We studied thermal adaptation in four wild populations and one hatchery stock of westslope cutthroat trout Oncorhynchus clarkii lewisi . The mean summer temperatures of source streams ranged from 6.7°C to 11.2°C. Embryos were collected from the wild, and embryonic development, embryonic survival, and juvenile growth were determined. A significant relationship between median embryonic survival and source stream temperature was detected. Based on a rank test, populations from colder streams had a greater decline in median embryonic survival at warm temperatures than populations from warmer streams. Embryonic development and juvenile growth did not appear to be influenced by source. These findings suggest that populations are thermally adapted to their source streams and this should be considered by managers. However, further study is necessary to sort out the potential confounding factors, whether genetic or epigenetic.
Huff, David D.; Miller, Loren M.; Vondracek, Bruce C.
2010-01-01
Reintroductions are a common approach for preserving intraspecific biodiversity in fragmented landscapes. However, they may exacerbate the reduction in genetic diversity initially caused by population fragmentation because the effective population size of reintroduced populations is often smaller and reintroduced populations also tend to be more geographically isolated than native populations. Mixing genetically divergent sources for reintroduction purposes is a practice intended to increase genetic diversity. We documented the outcome of reintroductions from three mixed sources on the ancestral composition and genetic variation of a North American fish, the slimy sculpin (Cottus cognatus). We used microsatellite markers to evaluate allelic richness and heterozygosity in the reintroduced populations relative to computer simulated expectations. Sculpins in reintroduced populations exhibited higher levels of heterozygosity and allelic richness than any single source, but only slightly higher than the single most genetically diverse source population. Simulations intended to mimic an ideal scenario for maximizing genetic variation in the reintroduced populations also predicted increases, but they were only moderately greater than the most variable source population. We found that a single source contributed more than the other two sources at most reintroduction sites. We urge caution when choosing whether to mix source populations in reintroduction programs. Genetic characteristics of candidate source populations should be evaluated prior to reintroduction if feasible. When combined with knowledge of the degree of genetic distinction among sources, simulations may allow the genetic diversity benefits of mixing populations to be weighed against the risks of outbreeding depression in reintroduced and nearby populations.
Huff, D.D.; Miller, L.M.; Vondracek, B.
2010-01-01
Reintroductions are a common approach for preserving intraspecific biodiversity in fragmented landscapes. However, they may exacerbate the reduction in genetic diversity initially caused by population fragmentation because the effective population size of reintroduced populations is often smaller and reintroduced populations also tend to be more geographically isolated than native populations. Mixing genetically divergent sources for reintroduction purposes is a practice intended to increase genetic diversity. We documented the outcome of reintroductions from three mixed sources on the ancestral composition and genetic variation of a North American fish, the slimy sculpin (Cottus cognatus). We used microsatellite markers to evaluate allelic richness and heterozygosity in the reintroduced populations relative to computer simulated expectations. Sculpins in reintroduced populations exhibited higher levels of heterozygosity and allelic richness than any single source, but only slightly higher than the single most genetically diverse source population. Simulations intended to mimic an ideal scenario for maximizing genetic variation in the reintroduced populations also predicted increases, but they were only moderately greater than the most variable source population. We found that a single source contributed more than the other two sources at most reintroduction sites. We urge caution when choosing whether to mix source populations in reintroduction programs. Genetic characteristics of candidate source populations should be evaluated prior to reintroduction if feasible. When combined with knowledge of the degree of genetic distinction among sources, simulations may allow the genetic diversity benefits of mixing populations to be weighed against the risks of outbreeding depression in reintroduced and nearby populations. ?? 2010 US Government.
Raghavan, Ramesh; Camarata, Stephen; White, Karl; Barbaresi, William; Parish, Susan; Krahn, Gloria
2018-05-17
The aim of the study was to provide an overview of population science as applied to speech and language disorders, illustrate data sources, and advance a research agenda on the epidemiology of these conditions. Computer-aided database searches were performed to identify key national surveys and other sources of data necessary to establish the incidence, prevalence, and course and outcome of speech and language disorders. This article also summarizes a research agenda that could enhance our understanding of the epidemiology of these disorders. Although the data yielded estimates of prevalence and incidence for speech and language disorders, existing sources of data are inadequate to establish reliable rates of incidence, prevalence, and outcomes for speech and language disorders at the population level. Greater support for inclusion of speech and language disorder-relevant questions is necessary in national health surveys to build the population science in the field.
Jamie Marie Marranca,; Amy Welsh,; Roseman, Edward F.
2015-01-01
Lake sturgeon (Acipenser fulvescens) have experienced significant habitat loss, resulting in reduced population sizes. Three artificial reefs were built in the Huron-Erie corridor in the Great Lakes to replace lost spawning habitat. Genetic data were collected to determine the source and numbers of adult lake sturgeon spawning on the reefs and to determine if the founder effect resulted in reduced genetic diversity. DNA was extracted from larval tail clips and 12 microsatellite loci were amplified. Larval genotypes were then compared to 22 previously studied spawning lake sturgeon populations in the Great Lakes to determine the source of the parental population. The effective number of breeders (Nb) was calculated for each reef cohort. The larval genotypes were then compared to the source population to determine if there were any losses in genetic diversity that are indicative of the founder effect. The St. Clair and Detroit River adult populations were found to be the source parental population for the larvae collected on all three artificial reefs. There were large numbers of contributing adults relative to the number of sampled larvae. There was no significant difference between levels of genetic diversity in the source population and larval samples from the artificial reefs; however, there is some evidence for a genetic bottleneck in the reef populations likely due to the founder effect. Habitat restoration in the Huron-Erie corridor is likely resulting in increased habitat for the large lake sturgeon population in the system and in maintenance of the population's genetic diversity.
Jesenšek, Dušan; Crivelli, Alain J.
2018-01-01
We develop a general framework that combines long-term tag–recapture data and powerful statistical and modelling techniques to investigate how population, environmental and climate factors determine variation in vital rates and population dynamics in an animal species, using as a case study the population of brown trout living in Upper Volaja (Western Slovenia). This population has been monitored since 2004. Upper Volaja is a sink, receiving individuals from a source population living above a waterfall. We estimate the numerical contribution of the source population on the sink population and test the effects of temperature, population density and extreme events on variation in vital rates among 2647 individually tagged brown trout. We found that individuals dispersing downstream from the source population help maintain high population densities in the sink population despite poor recruitment. The best model of survival for individuals older than juveniles includes additive effects of birth cohort and sampling occasion. Fast growth of older cohorts and higher population densities in 2004–2005 suggest very low population densities in the late 1990s, which we hypothesize were caused by a flash flood that strongly reduced population size and created the habitat conditions for faster individual growth and transient higher population densities after the extreme event. PMID:29657746
Vincenzi, Simone; Jesenšek, Dušan; Crivelli, Alain J
2018-03-01
We develop a general framework that combines long-term tag-recapture data and powerful statistical and modelling techniques to investigate how population, environmental and climate factors determine variation in vital rates and population dynamics in an animal species, using as a case study the population of brown trout living in Upper Volaja (Western Slovenia). This population has been monitored since 2004. Upper Volaja is a sink, receiving individuals from a source population living above a waterfall. We estimate the numerical contribution of the source population on the sink population and test the effects of temperature, population density and extreme events on variation in vital rates among 2647 individually tagged brown trout. We found that individuals dispersing downstream from the source population help maintain high population densities in the sink population despite poor recruitment. The best model of survival for individuals older than juveniles includes additive effects of birth cohort and sampling occasion. Fast growth of older cohorts and higher population densities in 2004-2005 suggest very low population densities in the late 1990s, which we hypothesize were caused by a flash flood that strongly reduced population size and created the habitat conditions for faster individual growth and transient higher population densities after the extreme event.
Open-Source Data and the Study of Homicide.
Parkin, William S; Gruenewald, Jeff
2015-07-20
To date, no discussion has taken place in the social sciences as to the appropriateness of using open-source data to augment, or replace, official data sources in homicide research. The purpose of this article is to examine whether open-source data have the potential to be used as a valid and reliable data source in testing theory and studying homicide. Official and open-source homicide data were collected as a case study in a single jurisdiction over a 1-year period. The data sets were compared to determine whether open-sources could recreate the population of homicides and variable responses collected in official data. Open-source data were able to replicate the population of homicides identified in the official data. Also, for every variable measured, the open-sources captured as much, or more, of the information presented in the official data. Also, variables not available in official data, but potentially useful for testing theory, were identified in open-sources. The results of the case study show that open-source data are potentially as effective as official data in identifying individual- and situational-level characteristics, provide access to variables not found in official homicide data, and offer geographic data that can be used to link macro-level characteristics to homicide events. © The Author(s) 2015.
Cransveld, Alice; Amouroux, David; Tessier, Emmanuel; Koutrakis, Emmanuil; Ozturk, Ayaka A; Bettoso, Nicola; Mieiro, Cláudia L; Bérail, Sylvain; Barre, Julien P G; Sturaro, Nicolas; Schnitzler, Joseph; Das, Krishna
2017-11-07
Our study reports the first data on mercury (Hg) isotope composition in marine European fish, for seven distinct populations of the European seabass, Dicentrarchus labrax. The use of δ 202 Hg and Δ 199 Hg values in SIBER enabled us to estimate Hg isotopic niches, successfully discriminating several populations. Recursive-partitioning analyses demonstrated the relevance of Hg stable isotopes as discriminating tools. Hg isotopic values also provided insight on Hg contamination sources for biota in coastal environment. The overall narrow range of δ 202 Hg around Europe was suggested to be related to a global atmospheric contamination while δ 202 Hg at some sites was linked either to background contamination, or with local contamination sources. Δ 199 Hg was related to Hg levels of fish but we also suggest a relation with ecological conditions. Throughout this study, results from the Black Sea population stood out, displaying a Hg cycling similar to fresh water lakes. Our findings bring out the possibility to use Hg isotopes in order to discriminate distinct populations, to explore the Hg cycle on a large scale (Europe) and to distinguish sites contaminated by global versus local Hg source. The interest of using Hg sable isotopes to investigate the whole European Hg cycle is clearly highlighted.
Williams, Evelyn; Bilge, Arman; Kramer, Andrea T.
2018-01-01
For many species and seed sources used in restoration activities, specific seed germination requirements are often unknown. Because seed dormancy and germination traits can be constrained by phylogenetic history, related species are often assumed to have similar traits. However, significant variation in these traits is also present within species as a result of adaptation to local climatic conditions. A growing number of studies have attempted to disentangle how phylogeny and climate influence seed dormancy and germination traits, but they have focused primarily on species-level effects, ignoring potential population-level variation. We examined the relationships between phylogeny, climate, and seed dormancy and germination traits for 24 populations of eight native, restoration-relevant forb species found in a wide range of climatic conditions in the Southwest United States. The seeds were exposed to eight temperature and stratification length regimes designed to mimic regional climatic conditions. Phylogenetic relatedness, overall climatic conditions, and temperature conditions at the site were all significantly correlated with final germination response, with significant among-population variation in germination response across incubation treatments for seven of our eight study species. Notably, germination during stratification was significantly predicted by precipitation seasonality and differed significantly among populations for seven species. While previous studies have not examined germination during stratification as a potential trait influencing overall germination response, our results suggest that this trait should be included in germination studies as well as seed sourcing decisions. Results of this study deepen our understanding of the relationships between source climate, species identity, and germination, leading to improved seed sourcing decisions for restorations. PMID:29401470
The Advanced Gamma-ray Imaging System (AGIS): Galactic Astrophysics
NASA Astrophysics Data System (ADS)
Digel, Seth William; Funk, S.; Kaaret, P. E.; Tajima, H.; AGIS Collaboration
2010-03-01
The Advanced Gamma-ray Imaging System (AGIS), a concept for a next-generation atmospheric Cherenkov telescope array, would provide unprecedented sensitivity and resolution in the energy range >50 GeV, allowing great advances in the understanding of the populations and physics of sources of high-energy gamma rays in the Milky Way. Extrapolation based on the known source classes and the performance parameters for AGIS indicates that a survey of the Galactic plane with AGIS will reveal hundreds of TeV sources in exquisite detail, for population studies of a variety of source classes, and detailed studies of individual sources. AGIS will be able to study propagation effects on the cosmic rays produced by Galactic sources by detecting the diffuse glow from their interactions in dense interstellar gas. AGIS will complement and extend results now being obtained in the GeV range with the Fermi mission, by providing superior angular resolution and sensitivity to variability on short time scales, and of course by probing energies that Fermi cannot reach.
High-energy sources at low radio frequency: the Murchison Widefield Array view of Fermi blazars
Giroletti, M.; Massaro, F.; D’Abrusco, R.; ...
2016-04-01
Low-frequency radio arrays are opening a new window for the study of the sky, both to study new phenomena and to better characterize known source classes. Being flat-spectrum sources, blazars are so far poorly studied at low radio frequencies. In this paper, we characterize the spectral properties of the blazar population at low radio frequency, compare the radio and high-energy properties of the gamma-ray blazar population, and search for radio counterparts of unidentified gamma-ray sources. We cross-correlated the 6100 deg 2 Murchison Widefield Array Commissioning Survey catalogue with the Roma blazar catalogue, the third catalogue of active galactic nuclei detectedmore » by Fermi-LAT, and the unidentified members of the entire third catalogue of gamma-ray sources detected by Fermi-LAT. When available, we also added high-frequency radio data from the Australia Telescope 20 GHz catalogue. We find low-frequency counterparts for 186 out of 517 (36%) blazars, 79 out of 174 (45%) gamma-ray blazars, and 8 out of 73 (11%) gamma-ray blazar candidates. The mean low-frequency (120–180 MHz) blazar spectral index is (α low) = 0.57 ± 0.02: blazar spectra are flatter than the rest of the population of low-frequency sources, but are steeper than at ~GHz frequencies. Low-frequency radio flux density and gamma-ray energy flux display a mildly significant and broadly scattered correlation. Ten unidentified gamma-ray sources have a (probably fortuitous) positional match with low radio frequency sources. Low-frequency radio astronomy provides important information about sources with a flat radio spectrum and high energy. However, the relatively low sensitivity of the present surveys still misses a significant fraction of these objects. Finally, upcoming deeper surveys, such as the GaLactic and Extragalactic All-Sky MWA (GLEAM) survey, will provide further insight into this population.« less
High-energy sources at low radio frequency: the Murchison Widefield Array view of Fermi blazars
DOE Office of Scientific and Technical Information (OSTI.GOV)
Giroletti, M.; Massaro, F.; D’Abrusco, R.
Low-frequency radio arrays are opening a new window for the study of the sky, both to study new phenomena and to better characterize known source classes. Being flat-spectrum sources, blazars are so far poorly studied at low radio frequencies. In this paper, we characterize the spectral properties of the blazar population at low radio frequency, compare the radio and high-energy properties of the gamma-ray blazar population, and search for radio counterparts of unidentified gamma-ray sources. We cross-correlated the 6100 deg 2 Murchison Widefield Array Commissioning Survey catalogue with the Roma blazar catalogue, the third catalogue of active galactic nuclei detectedmore » by Fermi-LAT, and the unidentified members of the entire third catalogue of gamma-ray sources detected by Fermi-LAT. When available, we also added high-frequency radio data from the Australia Telescope 20 GHz catalogue. We find low-frequency counterparts for 186 out of 517 (36%) blazars, 79 out of 174 (45%) gamma-ray blazars, and 8 out of 73 (11%) gamma-ray blazar candidates. The mean low-frequency (120–180 MHz) blazar spectral index is (α low) = 0.57 ± 0.02: blazar spectra are flatter than the rest of the population of low-frequency sources, but are steeper than at ~GHz frequencies. Low-frequency radio flux density and gamma-ray energy flux display a mildly significant and broadly scattered correlation. Ten unidentified gamma-ray sources have a (probably fortuitous) positional match with low radio frequency sources. Low-frequency radio astronomy provides important information about sources with a flat radio spectrum and high energy. However, the relatively low sensitivity of the present surveys still misses a significant fraction of these objects. Finally, upcoming deeper surveys, such as the GaLactic and Extragalactic All-Sky MWA (GLEAM) survey, will provide further insight into this population.« less
Trans Fat Intake and Its Dietary Sources in General Populations Worldwide: A Systematic Review
Wanders, Anne J.; Zock, Peter L.; Brouwer, Ingeborg A.
2017-01-01
After the discovery that trans fat increases the risk of coronary heart disease, trans fat content of foods have considerably changed. The aim of this study was to systematically review available data on intakes of trans fat and its dietary sources in general populations worldwide. Data from national dietary surveys and population studies published from 1995 onward were searched via Scopus and websites of national public health institutes. Relevant data from 29 countries were identified. The most up to date estimates of total trans fat intake ranged from 0.3 to 4.2 percent of total energy intake (En%) across countries. Seven countries had trans fat intakes higher than the World Health Organization recommendation of 1 En%. In 16 out of 21 countries with data on dietary sources, intakes of trans fat from animal sources were higher than that from industrial sources. Time trend data from 20 countries showed substantial declines in industrial trans fat intake since 1995. In conclusion, nowadays, in the majority of countries for which data are available, average trans fat intake is lower than the recommended maximum intake of 1 En%, with intakes from animal sources being higher than from industrial sources. In the past 20 years, substantial reductions in industrial trans fat have been achieved in many countries. PMID:28783062
Brameld, Kate; Spilsbury, Katrina; Rosenwax, Lorna; Murray, Kevin; Semmens, James
2017-06-01
Studies aiming to identify palliative care populations have used data from death certificates and in some cases hospital records. The size and characteristics of the identified populations can show considerable variation depending on the data sources used. It is important that service planners and researchers are aware of this. To illustrate the differences in the size and characteristics of a potential palliative care population depending on the differential use of linked hospital records and death certificate data. Retrospective cohort study. The cohort consisted of 23,852 people aged 20 years and over who died in Western Australia between 1 January 2009 and 31 December 2010 after excluding deaths related to pregnancy or trauma. Within this cohort, the number, proportion and characteristics of people who died from one or more of 10 medical conditions considered amenable to palliative care were identified using linked hospital records and death certificate data. Depending on the information source(s) used, between 43% and 73% of the 23,852 people who died had a condition potentially amenable to palliative care identified. The median age at death and the sex distribution of the decedents by condition also varied with the information source. Health service planners and researchers need to be aware of the limitations when using hospital records and death certificate data to determine a potential palliative care population. The use of Emergency Department and other administrative data sources could further exacerbate this variation.
Tanaka, Naoaki; Papadelis, Christos; Tamilia, Eleonora; Madsen, Joseph R; Pearl, Phillip L; Stufflebeam, Steven M
2018-04-27
This study evaluates magnetoencephalographic (MEG) spike population as compared with intracranial electroencephalographic (IEEG) spikes using a quantitative method based on distributed source analysis. We retrospectively studied eight patients with medically intractable epilepsy who had an MEG and subsequent IEEG monitoring. Fifty MEG spikes were analyzed in each patient using minimum norm estimate. For individual spikes, each vertex in the source space was considered activated when its source amplitude at the peak latency was higher than a threshold, which was set at 50% of the maximum amplitude over all vertices. We mapped the total count of activation at each vertex. We also analyzed 50 IEEG spikes in the same manner over the intracranial electrodes and created the activation count map. The location of the electrodes was obtained in the MEG source space by coregistering postimplantation computed tomography to MRI. We estimated the MEG- and IEEG-active regions associated with the spike populations using the vertices/electrodes with a count over 25. The activation count maps of MEG spikes demonstrated the localization associated with the spike population by variable count values at each vertex. The MEG-active region overlapped with 65 to 85% of the IEEG-active region in our patient group. Mapping the MEG spike population is valid for demonstrating the trend of spikes clustering in patients with epilepsy. In addition, comparison of MEG and IEEG spikes quantitatively may be informative for understanding their relationship.
Description of small-scale fluctuations in the diffuse X-ray background.
NASA Technical Reports Server (NTRS)
Cavaliere, A.; Friedland, A.; Gursky, H.; Spada, G.
1973-01-01
An analytical study of the fluctuations on a small angular scale expected in the diffuse X-ray background in the presence of unresolved sources is presented. The source population is described by a function N(S), giving the number of sources per unit solid angle and unit apparent flux S. The distribution of observed flux, s, in each angular resolution element of a complete sky survey is represented by a function Q(s). The analytical relation between the successive, higher-order moments of N(S) and Q(s) is described. The goal of reconstructing the source population from the study of the moments of Q(s) of order higher than the second (i.e., the rms fluctuations) is discussed.
Population: A Lively Introduction.
ERIC Educational Resources Information Center
McFalls, Joseph A., Jr.
1991-01-01
The study of demography must begin with an understanding of the three sources of population changes: fertility, mortality, and migration. This paper leads prospective demographers--or anyone interested in population--through the dynamics of these three variables, introducing them to the forces that cause populations to grow or decline, and that…
AMI-LA observations of the SuperCLASS supercluster
NASA Astrophysics Data System (ADS)
Riseley, C. J.; Grainge, K. J. B.; Perrott, Y. C.; Scaife, A. M. M.; Battye, R. A.; Beswick, R. J.; Birkinshaw, M.; Brown, M. L.; Casey, C. M.; Demetroullas, C.; Hales, C. A.; Harrison, I.; Hung, C.-L.; Jackson, N. J.; Muxlow, T.; Watson, B.; Cantwell, T. M.; Carey, S. H.; Elwood, P. J.; Hickish, J.; Jin, T. Z.; Razavi-Ghods, N.; Scott, P. F.; Titterington, D. J.
2018-03-01
We present a deep survey of the Super-Cluster Assisted Shear Survey (SuperCLASS) supercluster - a region of sky known to contain five Abell clusters at redshift z ˜ 0.2 - performed using the Arcminute Microkelvin Imager (AMI) Large Array (LA) at 15.5 GHz. Our survey covers an area of approximately 0.9 deg2. We achieve a nominal sensitivity of 32.0 μJy beam-1 towards the field centre, finding 80 sources above a 5σ threshold. We derive the radio colour-colour distribution for sources common to three surveys that cover the field and identify three sources with strongly curved spectra - a high-frequency-peaked source and two GHz-peaked-spectrum sources. The differential source count (i) agrees well with previous deep radio source counts, (ii) exhibits no evidence of an emerging population of star-forming galaxies, down to a limit of 0.24 mJy, and (iii) disagrees with some models of the 15 GHz source population. However, our source count is in agreement with recent work that provides an analytical correction to the source count from the Square Kilometre Array Design Study (SKADS) Simulated Sky, supporting the suggestion that this discrepancy is caused by an abundance of flat-spectrum galaxy cores as yet not included in source population models.
Population demographics and genetic diversity in remnant and translocated populations of sea otters
Bodkin, James L.; Ballachey, Brenda E.; Cronin, M.A.; Scribner, K.T.
1999-01-01
The effects of small population size on genetic diversity and subsequent population recovery are theoretically predicted, but few empirical data are available to describe those relations. We use data from four remnant and three translocated sea otter (Enhydra lutris) populations to examine relations among magnitude and duration of minimum population size, population growth rates, and genetic variation. Metochondrial (mt)DNA haplotype diversity was correlated with the number of years at minimum population size (r = -0.741, p = 0.038) and minimum population size (r = 0.709, p = 0.054). We found no relation between population growth and haplotype diversity, altough growth was significantly greater in translocated than in remnant populations. Haplotype diversity in populations established from two sources was higher than in a population established from a single source and was higher than in the respective source populations. Haplotype frequencies in translocated populations of founding sizes of 4 and 28 differed from expected, indicating genetic drift and differential reproduction between source populations, whereas haplotype frequencies in a translocated population with a founding size of 150 did not. Relations between population demographics and genetic characteristics suggest that genetic sampling of source and translocated populations can provide valuable inferences about translocations.
NASA Technical Reports Server (NTRS)
Ghosh, Kajal K.; Swartz, Douglas A.; Tennant, Allyn F.; Saripalli, Lakshmi; Gandhi, Poshak; Foellmi, Cedric; Gutierrez, Carlos M.; Lopez-Corredoira, Martin
2006-01-01
The X-ray source population in the field of the interacting pair of galaxies NGC 5774/5775 is reported. A total of 49 discrete sources are detected, including 12 ultraluminous X-ray source candidates with lum inosities above 10(exp 39)erg/s in the 0.5 - 8.0 keV X-ray band. Several of these latter are transient X-ray sources that fall below detect ion levels in one of two X-ray observations spaced 15 months apart. X-ray source positions are mapped onto optical and radio images to sear ch for potential counterparts. Eleven sources have optically-bright c ounterparts. Optical colors are used to differentiate these sources, which are mostly located outside the optical extent of the interacting galaxies, as potential globular clusters (3 sources) and quasars (5) . Follow-up optical spectroscopy confirms two of the latter are background quasars.
Black, D; Gates, G; Sanders, S; Taylor, L
2000-05-01
This work provides an overview of standard social science data sources that now allow some systematic study of the gay and lesbian population in the United States. For each data source, we consider how sexual orientation can be defined, and we note the potential sample sizes. We give special attention to the important problem of measurement error, especially the extent to which individuals recorded as gay and lesbian are indeed recorded correctly. Our concern is that because gays and lesbians constitute a relatively small fraction of the population, modest measurement problems could lead to serious errors in inference. In examining gays and lesbians in multiple data sets we also achieve a second objective: We provide a set of statistics about this population that is relevant to several current policy debates.
Community health information sources--a survey in three disparate communities.
Dart, Jared; Gallois, Cindy; Yellowlees, Peter
2008-02-01
To determine the current utilisation, importance, trust and future preference for contemporary sources of health information in three different socioeconomic groups. A pilot study including key informant interviews and direct observation was conducted in a low socioeconomic community. From this work a survey questionnaire was designed and implemented across three different communities. Semi-structured key informant interviews and focus groups capturing 52 respondents. Paper-based surveys were left in community organisations and local health practices in a low socioeconomic (LSE) community on the outskirts of Ipswich, Queensland, a mid-high socioeconomic (MSE) community in the western suburbs of Brisbane, and at a local university. Rank of current and preferred future sources of health information, importance and trustworthiness of health information sources. Across all three communities the local doctor was the most currently used, important, trusted and preferred future source of health information. The most striking difference between the three communities related to the current use and preferred future use of the internet. The internet was a more currently used source of health information and more important source in the university population than the LSE or MSE populations. It was also a less preferred source of future health information in the LSE population than the MSE or university populations. Importantly, currently used sources of health information did not reflect community members' preferred sources of health information. People in different socioeconomic communities obtain health information from various sources. This may reflect access issues, education and awareness of the internet as a source of health information, less health information seeking as well as a reluctance by the e-health community to address the specific needs of this group.
Effects of different sources of physically effective fiber on rumen microbial populations.
Shaw, C N; Kim, M; Eastridge, M L; Yu, Z
2016-03-01
Physically effective fiber is needed by dairy cattle to prevent ruminal acidosis. This study aimed to examine the effects of different sources of physically effective fiber on the populations of fibrolytic bacteria and methanogens. Five ruminally cannulated Holstein cows were each fed five diets differing in physically effective fiber sources over 15 weeks (21 days/period) in a Latin Square design: (1) 44.1% corn silage, (2) 34.0% corn silage plus 11.5% alfalfa hay, (3) 34.0% corn silage plus 5.1% wheat straw, (4) 36.1% corn silage plus 10.1% wheat straw, and (5) 34.0% corn silage plus 5.5% corn stover. The impact of the physically effective fiber sources on total bacteria and archaea were examined using denaturing gradient gel electrophoresis. Specific real-time PCR assays were used to quantify total bacteria, total archaea, the genus Butyrivibrio, Fibrobacter succinogenes, Ruminococcus albus, Ruminococcus flavefaciens and three uncultured rumen bacteria that were identified from adhering ruminal fractions in a previous study. No significant differences were observed among the different sources of physical effective fiber with respect to the microbial populations quantified. Any of the physically effective fiber sources may be fed to dairy cattle without negative impact on the ruminal microbial community.
Duarte, Ida Alzira Gomes; Hafner, Mariana de Figueiredo Silva; Malvestiti, Andrey Augusto
2015-01-01
The frequent human exposure to various types of indoor lamps, as well as other light sources (television monitors, tablets and computers), raises a question: are there risks for the population? In the present study the emission of UVA and UVB radiation by lamps and screens of electronic devices were measured in order to determine the safe distance between the emitting source and the individual. We concluded that the lamps and electronic devices do not emit ultraviolet radiation; so they pose no health risk for the population.
Duarte, Ida Alzira Gomes; Hafner, Mariana de Figueiredo Silva; Malvestiti, Andrey Augusto
2015-01-01
The frequent human exposure to various types of indoor lamps, as well as other light sources (television monitors, tablets and computers), raises a question: are there risks for the population? In the present study the emission of UVA and UVB radiation by lamps and screens of electronic devices were measured in order to determine the safe distance between the emitting source and the individual. We concluded that the lamps and electronic devices do not emit ultraviolet radiation; so they pose no health risk for the population. PMID:26375236
There is a perception among the population of the border communities that they have increased exposure due to their proximity to pollution sources in Mexico. This study provides exposure data for the border population that will be compared with data from a probabilistic exposure...
Bounds on the dynamics of sink populations with noisy immigration.
Eager, Eric Alan; Guiver, Chris; Hodgson, Dave; Rebarber, Richard; Stott, Iain; Townley, Stuart
2014-03-01
Sink populations are doomed to decline to extinction in the absence of immigration. The dynamics of sink populations are not easily modelled using the standard framework of per capita rates of immigration, because numbers of immigrants are determined by extrinsic sources (for example, source populations, or population managers). Here we appeal to a systems and control framework to place upper and lower bounds on both the transient and future dynamics of sink populations that are subject to noisy immigration. Immigration has a number of interpretations and can fit a wide variety of models found in the literature. We apply the results to case studies derived from published models for Chinook salmon (Oncorhynchus tshawytscha) and blowout penstemon (Penstemon haydenii). Copyright © 2013 Elsevier Inc. All rights reserved.
A primary goal of our research is to validate the use of urinary biomarkers to apportion the sources of human exposure to PM2.5. Organic source tracers have been used in source apportionment studies of ambient PM2.5 to distinguish a range of combustion sources. Both gas and par...
Freezer anthropology: new uses for old blood.
Merriwether, D A
1999-01-01
Archived blood fractions (plasma, settled red cells, white cells) have proved to be a rich and valuable source of DNA for human genetic studies. Large numbers of such samples were collected between 1960 and the present for protein and blood group studies, many of which are languishing in freezers or have already been discarded. More are discarded each year because the usefulness of these samples is not widely understood. Data from DNA derived from 10-35-year-old blood samples have been used to address the peopling of the New World and of the Pacific. Mitochondrial DNA haplotypes from studies using this source DNA support a single wave of migration into the New World (or a single source population for the New World), and that Mongolia was the likely source of the founding population. Data from Melanesia have shown that Polynesians are recent immigrants into the Pacific and did not arise from Melanesia. PMID:10091252
Estimating chronic disease rates in Canada: which population-wide denominator to use?
Ellison, J; Nagamuthu, C; Vanderloo, S; McRae, B; Waters, C
2016-10-01
Chronic disease rates are produced from the Public Health Agency of Canada's Canadian Chronic Disease Surveillance System (CCDSS) using administrative health data from provincial/territorial health ministries. Denominators for these rates are based on estimates of populations derived from health insurance files. However, these data may not be accessible to all researchers. Another source for population size estimates is the Statistics Canada census. The purpose of our study was to calculate the major differences between the CCDSS and Statistics Canada's population denominators and to identify the sources or reasons for the potential differences between these data sources. We compared the 2009 denominators from the CCDSS and Statistics Canada. The CCDSS denominator was adjusted for the growth components (births, deaths, emigration and immigration) from Statistics Canada's census data. The unadjusted CCDSS denominator was 34 429 804, 3.2% higher than Statistics Canada's estimate of population in 2009. After the CCDSS denominator was adjusted for the growth components, the difference between the two estimates was reduced to 431 323 people, a difference of 1.3%. The CCDSS overestimates the population relative to Statistics Canada overall. The largest difference between the two estimates was from the migrant growth component, while the smallest was from the emigrant component. By using data descriptions by data source, researchers can make decisions about which population to use in their calculations of disease frequency.
Restoration over time and sustainability of Schinus terebinthifolius Raddi.
Álvares-Carvalho, S V; Silva-Mann, R; Gois, I B; Melo, M F V; Oliveira, A S; Ferreira, R A; Gomes, L J
2017-05-31
The success of recovery programs on degraded areas is dependent on the genetic material to be used, which should present heterozygosity and genetic diversity in native and recovered populations. This study was carried out to evaluate the model efficiency to enable the recovery of a degraded area of the Lower São Francisco, Sergipe, Brazil. The target species for this study was Schinus terebinthifolius Raddi. Three populations were analyzed, the recovered area, seed-tree source population, and native tree population border established to the recovered area. The random amplified polymorphic DNA (RAPD) markers were used for diversity analysis. Genetic structure was estimated to evaluate the level of genetic variability existent in each population. There was no correlation between the spatial distribution and the genetic distances for all trees of the recovered area. The heterozygosity present in the recovered population was higher than the native tree population. The seed-tree source population presents genetic bottlenecks. Three clusters were suggested (ΔK = 3) with non-genetic structure. High intra-population genetic variability and inter-population differentiation are present. However, gene flow may also introduce potentially adaptive alleles in the populations of the recovered area, and the native population is necessary to ensure the sustainability and maintenance of the populations by allelic exchange.
Sample size of the reference sample in a case-augmented study.
Ghosh, Palash; Dewanji, Anup
2017-05-01
The case-augmented study, in which a case sample is augmented with a reference (random) sample from the source population with only covariates information known, is becoming popular in different areas of applied science such as pharmacovigilance, ecology, and econometrics. In general, the case sample is available from some source (for example, hospital database, case registry, etc.); however, the reference sample is required to be drawn from the corresponding source population. The required minimum size of the reference sample is an important issue in this regard. In this work, we address the minimum sample size calculation and discuss related issues. Copyright © 2017 John Wiley & Sons, Ltd. Copyright © 2017 John Wiley & Sons, Ltd.
Hardstaff, Joanne L; Bulling, Mark T; Marion, Glenn; Hutchings, Michael R; White, Piran C L
2012-06-27
The persistence of bovine TB (bTB) in various countries throughout the world is enhanced by the existence of wildlife hosts for the infection. In Britain and Ireland, the principal wildlife host for bTB is the badger (Meles meles). The objective of our study was to examine the dynamics of bTB in badgers in relation to both badger-derived infection from within the population and externally-derived, trickle-type, infection, such as could occur from other species or environmental sources, using a spatial stochastic simulation model. The presence of external sources of infection can increase mean prevalence and reduce the threshold group size for disease persistence. Above the threshold equilibrium group size of 6-8 individuals predicted by the model for bTB persistence in badgers based on internal infection alone, external sources of infection have relatively little impact on the persistence or level of disease. However, within a critical range of group sizes just below this threshold level, external infection becomes much more important in determining disease dynamics. Within this critical range, external infection increases the ratio of intra- to inter-group infections due to the greater probability of external infections entering fully-susceptible groups. The effect is to enable bTB persistence and increase bTB prevalence in badger populations which would not be able to maintain bTB based on internal infection alone. External sources of bTB infection can contribute to the persistence of bTB in badger populations. In high-density badger populations, internal badger-derived infections occur at a sufficient rate that the additional effect of external sources in exacerbating disease is minimal. However, in lower-density populations, external sources of infection are much more important in enhancing bTB prevalence and persistence. In such circumstances, it is particularly important that control strategies to reduce bTB in badgers include efforts to minimise such external sources of infection.
2012-01-01
Background The persistence of bovine TB (bTB) in various countries throughout the world is enhanced by the existence of wildlife hosts for the infection. In Britain and Ireland, the principal wildlife host for bTB is the badger (Meles meles). The objective of our study was to examine the dynamics of bTB in badgers in relation to both badger-derived infection from within the population and externally-derived, trickle-type, infection, such as could occur from other species or environmental sources, using a spatial stochastic simulation model. Results The presence of external sources of infection can increase mean prevalence and reduce the threshold group size for disease persistence. Above the threshold equilibrium group size of 6–8 individuals predicted by the model for bTB persistence in badgers based on internal infection alone, external sources of infection have relatively little impact on the persistence or level of disease. However, within a critical range of group sizes just below this threshold level, external infection becomes much more important in determining disease dynamics. Within this critical range, external infection increases the ratio of intra- to inter-group infections due to the greater probability of external infections entering fully-susceptible groups. The effect is to enable bTB persistence and increase bTB prevalence in badger populations which would not be able to maintain bTB based on internal infection alone. Conclusions External sources of bTB infection can contribute to the persistence of bTB in badger populations. In high-density badger populations, internal badger-derived infections occur at a sufficient rate that the additional effect of external sources in exacerbating disease is minimal. However, in lower-density populations, external sources of infection are much more important in enhancing bTB prevalence and persistence. In such circumstances, it is particularly important that control strategies to reduce bTB in badgers include efforts to minimise such external sources of infection. PMID:22738118
Shiqin Xu; C.G. Tauer; C. Dana Nelson
2008-01-01
Shortleaf pine (n=93) and loblolly pine (n=112) trees representing 22 seed sources or 16 physiographic populations were sampled from Southwide Southern Pine Seed Source Study plantings located in Oklahoma, Arkansas and Mississippi. The sampled trees were grown from shortleaf pine and loblolly pine seeds formed in 1951 and 1952, prior to the start of intensive forest...
Taïbi, K; del Campo, A D; Aguado, A; Mulet, J M
2016-04-15
Forest restoration constitutes an important issue within adaptive environmental management for climate change at global scale. However, effective implementation of these programs can only be achieved by revising current seed transfer guidelines, as they lack inherent spatial and temporal dynamics associated with climate change. In this sense, provenance trials may provide key information on the relative performance of different populations and/or genotypes under changing ecological conditions. This study addresses a methodological approach to evaluate early plantation performance and the consequent phenotypic plasticity and the pattern of the adaptation of different seed sources in contrasting environments. To this end, six seed sources of Salzmann pine were tested at three contrasting trial sites testing a hypothetical assisted population migration. Adaptation at each site was assessed through Joint Regression and Additive Main effect and Multiplication Interaction (AMMI) models. Most of the observed variation was attributed to the environment (above 90% for all traits), even so genotype and genotype by environment interaction (GxE) were significant. Seedlings out-planted under better site conditions did not differ in survival but in height growth. However, on sites with higher constraints, survival differed among seed sources and diameter growth was high. The adaptation analyses (AMMI) indicated that the cold-continental seed source 'Soria' performed as a generalist seed source, whereas 'Cordilleras Béticas', the southernmost seed source, was more adapted to harsh environments (frost and drought) in terms of survival. The results supported partially the hypothesis that assisted migration of seed sources makes sense within limited transfer distances, and this was reinforced by the GxE results. The present study could be valuable to address adaptive transfer of seedings in ecological restoration and to determine the suitable seed sources for reforestation programs and assisted population migration under climatic changes. The reported results are based on 3 years' data and need to be considered in this context. Copyright © 2016 Elsevier Ltd. All rights reserved.
A population of isolated hard X-ray sources near the supernova remnant Kes 69
NASA Astrophysics Data System (ADS)
Bocchino, F.; Bykov, A. M.; Chen, Y.; Krassilchtchikov, A. M.; Levenfish, K. P.; Miceli, M.; Pavlov, G. G.; Uvarov, Yu. A.; Zhou, X.
2012-05-01
Recent X-ray observations of the supernova remnant (SNR) IC 443 interacting with molecular clouds detected a new population of hard X-ray sources related to the remnant itself, which has been proposed to be fast ejecta fragments propagating within the dense environment. Encouraged by these studies, we obtained a deep XMM-Newton observation of the SNR Kes 69, which also shows signs of a shock-cloud interaction. We report on the detection of 18 hard X-ray sources in the field of Kes 69, which is a number sognificantly higher than expected for the Galactic source population in the field. The sources are spatially correlated with CO emission from the cloud in the remnant environment. The spectra of 3 of the 18 sources can be described as hard power-laws with photon indices smaller than two plus line emission associated with K-shell transitions. We discuss the two most promising scenarios for the interpretation of the sources, namely fast ejecta fragments (as in IC 443) and cataclysmic variables. While most of the observational evidence is consistent with the former interpretation, we cannot rule out the latter.
Magnússon, S H; Guðmundsdóttir, S; Reynisson, E; Rúnarsson, A R; Harðardóttir, H; Gunnarson, E; Georgsson, F; Reiersen, J; Marteinsson, V Th
2011-10-01
Campylobacter jejuni isolates from various sources in Iceland were genotyped with the aim of assessing the genetic diversity, population structure, source distribution and campylobacter transmission routes to humans. A collection of 584 Campylobacter isolates were collected from clinical cases, food, animals and environment in Iceland in 1999-2002, during a period of national Campylobacter epidemic in Iceland. All isolates were characterized by pulse field gel electrophoresis (PFGE), and selected subset of 52 isolates representing the diversity of the identified PFGE types was further genotyped using multilocus sequence typing (MLST) and fla-SVR sequencing to gain better insight into the population structure. The results show a substantial diversity within the Icelandic Campylobacter population. Majority of the human Campylobacter infections originated from domestic chicken and cattle isolates. MLST showed the isolates to be distributed among previously reported and common sequence type complexes in the MLST database. The genotyping of Campylobacter from various sources has not previously been reported from Iceland, and the results of the study gave a valuable insight into the population structure of Camp. jejuni in Iceland, source distribution and transmission routes to humans. The geographical isolation of Iceland in the north Atlantic provides new information on Campylobacter population dynamics on a global scale. Journal of Applied Microbiology © 2011 The Society for Applied Microbiology No claim to Icelandic Government works.
Drinking water intake and source patterns within a US-Mexico border population.
Regnier, Adam; Gurian, Patrick; Mena, Kristina D
2015-01-01
This study was undertaken to identify water intake and source patterns among a population that resides in a hot, arid region on the US-Mexico border. A cross-sectional community-based survey was conducted among households in the neighbouring cities of El Paso, TX, USA and Ciudad Juárez, Chihuahua, Mexico to obtain data on the quantity and source of water consumed. The study was also designed to identify factors that impact water consumption patterns, including gender, demographics, socio-economic status, cultural characteristics, health status, types of occupations and residences, available water sources and outdoor temperature, among many others. Of all factors studied, outdoor air temperature was found to have the strongest impact upon water intake quantity. Specifically, among the survey participants, when the outdoor air temperature exceeded 90 °F, water consumption increased by 28 %. Additionally, it was found that participants in this region consumed approximately 50 % more water than the values reported in previous studies.
Patterns of Genetic Variation across Altitude in Three Plant Species of Semi-Dry Grasslands
Hahn, Thomas; Kettle, Chris J.; Ghazoul, Jaboury; Frei, Esther R.; Matter, Philippe; Pluess, Andrea R.
2012-01-01
Background Environmental gradients caused by altitudinal gradients may affect genetic variation within and among plant populations and inbreeding within populations. Populations in the upper range periphery of a species may be important source populations for range shifts to higher altitude in response to climate change. In this study we investigate patterns of population genetic variation at upper peripheral and lower more central altitudes in three common plant species of semi-dry grasslands in montane landscapes. Methodology/Principal Findings In Briza media, Trifolium montanum and Ranunculus bulbosus genetic diversity, inbreeding and genetic relatedness of individuals within populations and genetic differentiation among populations was characterized using AFLP markers. Populations were sampled in the Swiss Alps at 1800 (upper periphery of the study organisms) and at 1200 m a.s.l. Genetic diversity was not affected by altitude and only in B. media inbreeding was greater at higher altitudes. Genetic differentiation was slightly greater among populations at higher altitudes in B. media and individuals within populations were more related to each other compared to individuals in lower altitude populations. A similar but less strong pattern of differentiation and relatedness was observed in T. montanum, while in R. bulbosus there was no effect of altitude. Estimations of population size and isolation of populations were similar, both at higher and lower altitudes. Conclusions/Significance Our results suggest that altitude does not affect genetic diversity in the grassland species under study. Genetic differentiation of populations increased only slightly at higher elevation, probably due to extensive (historic) gene flow among altitudes. Potentially pre-adapted genes might therefore spread easily across altitudes. Our study indicates that populations at the upper periphery are not genetically depauperate or isolated and thus may be important source populations for migration under climate change. PMID:22870236
Huff, D.D.; Miller, L.M.; Chizinski, C.J.; Vondracek, B.
2011-01-01
Reintroductions are commonly employed to preserve intraspecific biodiversity in fragmented landscapes. However, reintroduced populations are frequently smaller and more geographically isolated than native populations. Mixing genetically, divergent sources are often proposed to attenuate potentially low genetic diversity in reintroduced populations that may result from small effective population sizes. However, a possible negative tradeoff for mixing sources is outbreeding depression in hybrid offspring. We examined the consequences of mixed-source reintroductions on several fitness surrogates at nine slimy sculpin (Cottus cognatus) reintroduction sites in south-east Minnesota. We inferred the relative fitness of each crosstype in the reintroduced populations by comparing their growth rate, length, weight, body condition and persistence in reintroduced populations. Pure strain descendents from a single source population persisted in a greater proportion than expected in the reintroduced populations, whereas all other crosstypes occurred in a lesser proportion. Length, weight and growth rate were lower for second-generation intra-population hybrid descendents than for pure strain and first-generation hybrids. In the predominant pure strain, young-of the-year size was significantly greater than any other crosstype. Our results suggested that differences in fitness surrogates among crosstypes were consistent with disrupted co-adapted gene complexes associated with beneficial adaptations in these reintroduced populations. Future reintroductions may be improved by evaluating the potential for local adaptation in source populations or by avoiding the use of mixed sources by default when information on local adaptations or other genetic characteristics is lacking. ?? 2011 Blackwell Publishing Ltd.
Newby, Jesse R.; Mills, L. Scott; Ruth, Toni K.; Pletscher, Daniel H.; Mitchell, Michael S.; Quigley, Howard B.; Murphy, Kerry M.; DeSimone, Rich
2013-01-01
An understanding of how stressors affect dispersal attributes and the contribution of local populations to multi-population dynamics are of immediate value to basic and applied ecology. Puma (Puma concolor) populations are expected to be influenced by inter-population movements and susceptible to human-induced source–sink dynamics. Using long-term datasets we quantified the contribution of two puma populations to operationally define them as sources or sinks. The puma population in the Northern Greater Yellowstone Ecosystem (NGYE) was largely insulated from human-induced mortality by Yellowstone National Park. Pumas in the western Montana Garnet Mountain system were exposed to greater human-induced mortality, which changed over the study due to the closure of a 915 km2 area to hunting. The NGYE’s population growth depended on inter-population movements, as did its ability to act as a source to the larger region. The heavily hunted Garnet area was a sink with a declining population until the hunting closure, after which it became a source with positive intrinsic growth and a 16× increase in emigration. We also examined the spatial and temporal characteristics of individual dispersal attributes (emigration, dispersal distance, establishment success) of subadult pumas (N = 126). Human-caused mortality was found to negatively impact all three dispersal components. Our results demonstrate the influence of human-induced mortality on not only within population vital rates, but also inter-population vital rates, affecting the magnitude and mechanisms of local population’s contribution to the larger metapopulation.
Constraining the Milky Way's Faint HMXB Population Using Archival Data
NASA Astrophysics Data System (ADS)
Tomsick, John
2017-09-01
In the first 40 months of sensitive hard X-ray observations with the Nuclear Spectroscopic Telescope Array, nearly 500 sources have been detected serendipitously. While the effort to determine the nature of these sources has been very successful at high Galactic latitudes, identifications close to the Galactic plane have been more difficult because of source crowding and optical extinction. Only six 8-24 keV sources within 5 deg of the plane have been classified, and two of them are High-Mass X-ray Binaries (HMXBs), leaving open the possibility of a large population of faint HMXBs. We propose an archival study of 13 unclassified sources, including obtaining subarcsecond positions, which, along with joint near-IR imaging, will be used to find counterparts and determine their nature.
Spectral Index Properties of millijansky Radio Sources in ATLAS
NASA Astrophysics Data System (ADS)
Randall, Kate; Hopkins, A. M.; Norris, R. P.; Zinn, P.; Middelberg, E.; Mao, M. Y.; Sharp, R. G.
2012-01-01
At the faintest radio flux densities (S1.4GHz < 10 milliJansky (mJy)), the spectral index properties of radio sources are not well constrained. The bright radio source population (S1.4GHz > 10 mJy) is well studied and is predominantly comprised of AGN. At fainter flux densities, particularly into the microJansky regime, star-forming galaxies begin to dominate the radio source population. Understanding these faint radio source populations is essential for understanding galaxy evolution, and the link between AGN and star formation. Conflicting results have recently arisen regarding whether there is a flattening of the average spectral index between a low radio frequency (325 or 610 MHz) and 1.4 GHz at these faint flux densities. To explore this issue, we have investigated the spectral index properties of a new catalogue of 843 MHz radio sources in the ELAIS-S1 (the European Large Area ISO Survey - South 1 Region) field. Our results support previous work showing a tendency towards flatter radio spectra at fainter flux densities. This catalogue is cross-matched to the Australia Telescope Large Area Survey (ATLAS), the widest deep radio survey to date at 1.4 GHz, with complementary 2.3 GHz, optical and infrared Spitzer Wide-area Infra-Red Extragalactic data. The variation of spectral index properties have been explored as a function of redshift, luminosity and flux density. [These new measurements have been used to identify a population of faint Compact Steep Spectrum sources, thought to be one of the earliest stages of the AGN life-cycle. Exploring this population will aid us in understanding the evolution of AGN as a whole.
Information Sources and Retirement Savings of Working Women
ERIC Educational Resources Information Center
Hsua, Chungwen
2016-01-01
This study examined how retirement planning information search was related to retirement savings of working women. By controlling for sociodemographic variables, the study further explored factors associated with individual information sources for retirement planning. An online survey was developed to collect data from a national population,…
Deciphering the Routes of invasion of Drosophila suzukii by Means of ABC Random Forest.
Fraimout, Antoine; Debat, Vincent; Fellous, Simon; Hufbauer, Ruth A; Foucaud, Julien; Pudlo, Pierre; Marin, Jean-Michel; Price, Donald K; Cattel, Julien; Chen, Xiao; Deprá, Marindia; François Duyck, Pierre; Guedot, Christelle; Kenis, Marc; Kimura, Masahito T; Loeb, Gregory; Loiseau, Anne; Martinez-Sañudo, Isabel; Pascual, Marta; Polihronakis Richmond, Maxi; Shearer, Peter; Singh, Nadia; Tamura, Koichiro; Xuéreb, Anne; Zhang, Jinping; Estoup, Arnaud
2017-04-01
Deciphering invasion routes from molecular data is crucial to understanding biological invasions, including identifying bottlenecks in population size and admixture among distinct populations. Here, we unravel the invasion routes of the invasive pest Drosophila suzukii using a multi-locus microsatellite dataset (25 loci on 23 worldwide sampling locations). To do this, we use approximate Bayesian computation (ABC), which has improved the reconstruction of invasion routes, but can be computationally expensive. We use our study to illustrate the use of a new, more efficient, ABC method, ABC random forest (ABC-RF) and compare it to a standard ABC method (ABC-LDA). We find that Japan emerges as the most probable source of the earliest recorded invasion into Hawaii. Southeast China and Hawaii together are the most probable sources of populations in western North America, which then in turn served as sources for those in eastern North America. European populations are genetically more homogeneous than North American populations, and their most probable source is northeast China, with evidence of limited gene flow from the eastern US as well. All introduced populations passed through bottlenecks, and analyses reveal five distinct admixture events. These findings can inform hypotheses concerning how this species evolved between different and independent source and invasive populations. Methodological comparisons indicate that ABC-RF and ABC-LDA show concordant results if ABC-LDA is based on a large number of simulated datasets but that ABC-RF out-performs ABC-LDA when using a comparable and more manageable number of simulated datasets, especially when analyzing complex introduction scenarios. © The Author 2017. Published by Oxford University Press on behalf of the Society for Molecular Biology and Evolution.
Many studies of animal responses to ocean acidification focus on uniformly conditioned age cohorts that lack complexities typically found in wild populations. These studies have become the primary data source for predicting higher level ecological effects, but the roles of intras...
Massey, Philip M
2016-01-01
With more people turning to the Internet for health information, a few questions remain: Which populations represent the remaining few who have never used the Internet, and where do they go for health information? The purpose of this study is to describe population characteristics and sources of health information among U.S. adults who do not use the Internet. Data from 3 iterations of the Health Information National Trends Survey (n = 1,722) are used to examine trends in health information sources. Weighted predicted probabilities demonstrate changes in information source over time. Older adults, minority populations, and individuals with low educational attainment represent a growing percentage of respondents who have looked for health information but have never used the Internet, highlighting trends in digital information disparities. However, 1 in 10 respondents who have never used the Internet also indicate that the Internet was their first source of health information, presumably through surrogates. Findings highlight digital disparities in information seeking and the complex nature of online information seeking. Future research should examine how individuals conceptualize information sources, measure skills related to evaluating information and sources, and investigate the social nature of information seeking. Health care organizations and public health agencies can leverage the multifaceted nature of information seeking to better develop information resources to increase information access by vulnerable populations.
Rapid Monte Carlo Simulation of Gravitational Wave Galaxies
NASA Astrophysics Data System (ADS)
Breivik, Katelyn; Larson, Shane L.
2015-01-01
With the detection of gravitational waves on the horizon, astrophysical catalogs produced by gravitational wave observatories can be used to characterize the populations of sources and validate different galactic population models. Efforts to simulate gravitational wave catalogs and source populations generally focus on population synthesis models that require extensive time and computational power to produce a single simulated galaxy. Monte Carlo simulations of gravitational wave source populations can also be used to generate observation catalogs from the gravitational wave source population. Monte Carlo simulations have the advantes of flexibility and speed, enabling rapid galactic realizations as a function of galactic binary parameters with less time and compuational resources required. We present a Monte Carlo method for rapid galactic simulations of gravitational wave binary populations.
2014-01-01
Background African Americans have been treated as a representative population for African ancestry for many purposes, including pharmacogenomic studies. However, the contribution of European ancestry is expected to result in considerable differences in the genetic architecture of African American individuals compared with an African genome. In particular, the genetic admixture influences the genomic diversity of drug metabolism-related genes, and may cause high heterogeneity of drug responses in admixed populations such as African Americans. Results The genomic ancestry information of African-American (ASW) samples was obtained from data of the 1000 Genomes Project, and local ancestral components were also extracted for 32 core genes and 252 extended genes, which are associated with drug absorption, distribution, metabolism, and excretion (ADME) genes. As expected, the global genetic diversity pattern in ASW was determined by the contributions of its putative ancestral source populations, and the whole profiles of ADME genes in ASW are much closer to those in YRI than in CEU. However, we observed much higher diversity in some functionally important ADME genes in ASW than either CEU or YRI, which could be a result of either genetic drift or natural selection, and we identified some signatures of the latter. We analyzed the clinically relevant polymorphic alleles and haplotypes, and found that 28 functional mutations (including 3 missense, 3 splice, and 22 regulator sites) exhibited significantly higher differentiation between the three populations. Conclusions Analysis of the genetic diversity of ADME genes showed differentiation between admixed population and its ancestral source populations. In particular, the different genetic diversity between ASW and YRI indicated that the ethnic differences in pharmacogenomic studies are broadly existed despite that African ancestry is dominant in Africans Americans. This study should advance our understanding of the genetic basis of the drug response heterogeneity between populations, especially in the case of population admixture, and have significant implications for evaluating potential inter-population heterogeneity in drug treatment effects. PMID:24884825
Greco, Susan L; Wilson, Andrew M; Hanna, Steven R; Levy, Jonathan I
2007-11-15
Benefit-cost and regulatory impact analyses often use atmospheric dispersion models with coarse resolution to estimate the benefits of proposed mobile source emission control regulations. This approach may bias health estimates or miss important intra-urban variability for primary air pollutants. In this study, we estimate primary fine particulate matter (PM2.5) intake fractions (iF; the fraction of a pollutant emitted from a source that is inhaled by the population) for each of 23 398 road segments in the Boston Metro Core area to evaluate the potential for intra-urban variability in the emissions-to-exposure relationship. We estimate iFs using the CAL3QHCR line source model combined with residential populations within 5000 m of each road segment. The annual average values for the road segments range from 0.8 to 53 per million, with a mean of 12 per million. On average, 46% of the total exposure is realized within 200 m of the road segment, though this varies from 0 to 93% largely due to variable population patterns. Our findings indicate the likelihood of substantial intra-urban variability in mobile source primary PM2.5 iF that accounting for population movement with time, localized meteorological conditions, and street-canyon configurations would likely increase.
McCluney, Kevin E; Sabo, John L
2010-12-31
Fluxes of carbon, nitrogen, and water between ecosystem components and organisms have great impacts across levels of biological organization. Although much progress has been made in tracing carbon and nitrogen, difficulty remains in tracing water sources from the ecosystem to animals and among animals (the "water web"). Naturally occurring, non-radioactive isotopes of hydrogen and oxygen in water provide a potential method for tracing water sources. However, using this approach for terrestrial animals is complicated by a change in water isotopes within the body due to differences in activity of heavy and light isotopes during cuticular and transpiratory water losses. Here we present a technique to use stable water isotopes to estimate the mean mix of water sources in a population by sampling a group of sympatric animals over time. Strong correlations between H and O isotopes in the body water of animals collected over time provide linear patterns of enrichment that can be used to predict a mean mix of water sources useful in standard mixing models to determine relative source contribution. Multiple temperature and humidity treatment levels do not greatly alter these relationships, thus having little effect on our ability to estimate this population-level mix of water sources. We show evidence for the validity of using multiple samples of animal body water, collected across time, to estimate the isotopic mix of water sources in a population and more accurately trace water sources. The ability to use isotopes to document patterns of animal water use should be a great asset to biologists globally, especially those studying drylands, droughts, streamside areas, irrigated landscapes, and the effects of climate change.
Baeta, Miriam; Núñez, Carolina; Cardoso, Sergio; Palencia-Madrid, Leire; Piñeiro-Hermida, Sergio; Arriba-Barredo, Miren; Villanueva-Millán, María Jesús; M de Pancorbo, Marian
2015-01-01
The Basque Diaspora in Western USA and Argentina represents two populations which have maintained strong Basque cultural and social roots in a completely different geographic context. Hence, they provide an exceptional opportunity to study the maternal genetic legacy from the ancestral Basque population and assess the degree of genetic introgression from the host populations in two of the largest Basque communities outside the Basque Country. For this purpose, we analyzed the complete mitochondrial DNA control region of Basque descendants living in Western USA (n = 175) and in Argentina (n = 194). The Diaspora populations studied here displayed a genetic diversity in their European maternal input which was similar to that of the Basque source populations, indicating that not important founder effects would have occurred. Actually, the genetic legacy of the Basque population still prevailed in their present-day maternal pools, by means of a haplogroup distribution similar to the source population characterized by the presence of autochthonous Basque lineages, such as U5b1f1a and J1c5c1. However, introgression of non-Basque lineages, mostly Native American, has been observed in the Diaspora populations, particularly in Argentina, where the quick assimilation of the newcomers would have favored a wider admixture with host populations. In contrast, a longer isolation of the Diaspora groups in USA, because of language and cultural differences, would have limited the introgression of local lineages. This study reveals important differences in the maternal evolutionary histories of these Basque Diaspora populations, which have to be taken into consideration in forensic and medical genetic studies.
Adolescent Health Literacy: The Importance of Credible Sources for Online Health Information
ERIC Educational Resources Information Center
Ghaddar, Suad F.; Valerio, Melissa A.; Garcia, Carolyn M.; Hansen, Lucy
2012-01-01
Background: Little research has examined adolescent health literacy and its relationship with online health information sources. The purpose of this study is to explore health literacy among a predominantly Hispanic adolescent population and to investigate whether exposure to a credible source of online health information, MedlinePlus[R], is…
Analysis of Vertiport Studies Funded by the Airport Improvement Program (AIP)
1994-05-01
the general population and travel behavior factors from surveys and other sources. FEASIBILITY The vertiport studies recognize the need to address the ... behavior factors obtained from surveys and other sources. All of the methods were dependent upon various secondary data and/or information sources that...economic responses and of travel behavior . The five types, in order of increasing analytical sophistication, are briefly identified as follows. I
Daya, Michelle; van der Merwe, Lize; Galal, Ushma; Möller, Marlo; Salie, Muneeb; Chimusa, Emile R.; Galanter, Joshua M.; van Helden, Paul D.; Henn, Brenna M.; Gignoux, Chris R.; Hoal, Eileen
2013-01-01
Admixture is a well known confounder in genetic association studies. If genome-wide data is not available, as would be the case for candidate gene studies, ancestry informative markers (AIMs) are required in order to adjust for admixture. The predominant population group in the Western Cape, South Africa, is the admixed group known as the South African Coloured (SAC). A small set of AIMs that is optimized to distinguish between the five source populations of this population (African San, African non-San, European, South Asian, and East Asian) will enable researchers to cost-effectively reduce false-positive findings resulting from ignoring admixture in genetic association studies of the population. Using genome-wide data to find SNPs with large allele frequency differences between the source populations of the SAC, as quantified by Rosenberg et. al's -statistic, we developed a panel of AIMs by experimenting with various selection strategies. Subsets of different sizes were evaluated by measuring the correlation between ancestry proportions estimated by each AIM subset with ancestry proportions estimated using genome-wide data. We show that a panel of 96 AIMs can be used to assess ancestry proportions and to adjust for the confounding effect of the complex five-way admixture that occurred in the South African Coloured population. PMID:24376522
Ilacqua, Vito; Hänninen, Otto; Saarela, Kristina; Katsouyanni, Klea; Künzli, Nino; Jantunen, Matti
2007-10-01
Apportionment of urban particulate matter (PM) to sources is central for air quality management and efficient reduction of the substantial public health risks associated with fine particles (PM(2.5)). Traffic is an important source combustion particles, but also a significant source of resuspended particles that chemically resemble Earth's crust and that are not affected by development of cleaner motor technologies. A substantial fraction of urban ambient PM originates from long-range transport outside the immediate urban environment including secondary particles formed from gaseous emissions of mainly sulphur, nitrogen oxides and ammonia. Most source apportionment studies are based on small number of fixed monitoring sites and capture well population exposures to regional and long-range transported particles. However, concentrations from local sources are very unevenly distributed and the results from such studies are therefore poorly representative of the actual exposures. The current study uses PM(2.5) data observed at population based random sampled residential locations in Athens, Basle and Helsinki with 17 elemental constituents, selected VOCs (xylenes, trimethylbenzenes, nonane and benzene) and light absorbance (black smoke). The major sources identified across the three cities included crustal, salt, long-range transported inorganic and traffic sources. Traffic was associated separately with source categories with crustal (especially Athens and Helsinki) and long-range transported chemical composition (all cities). Remarkably high fractions of the variability of elemental (R(2)>0.6 except for Ca in Basle 0.38) and chemical concentrations (R(2)>0.5 except benzene in Basle 0.22 and nonane in Athens 0.39) are explained by the source factors of an SEM model. The RAINS model that is currently used as the main tool in developing European air quality management policies seems to capture the local urban fraction (the city delta term) quite well, but underestimates crustal particle levels in the three cities of the current study. Utilizing structural equation modelling parallel with traditional principal component analysis (PCA) provides an objective method to determine the number of factors to be retained in a model and allows for formal hypotheses testing.
Caldas, Aline Diniz Rodrigues; Santos, Ricardo Ventura; Borges, Gabriel Mendes; Valente, Joaquim Gonçalves; Portela, Margareth Crisóstomo; Marinho, Gerson Luiz
2017-08-07
The aim of this study was to investigate infant mortality data according to color or race in Brazil with a focus on indigenous individuals, based on data from the 2010 Population Census and the Brazilian Mortality Information System (SIM) and Brazilian Information System on Live Births (SINASC). In both sources, the infant mortality rate (IMR) for indigenous individuals was the highest of all the various population segments. Although the census data indicate inequalities by color or race, the infant mortality rates for indigenous and black individuals were lower than those based on data from SIM/SINASC. Methodological specificities in the data collection in the two sources should be considered. The reduction in IMR in Brazil in recent decades is largely attributed to the priority of infant health on the policy agenda. The study's findings indicate that the impact of public policies failed to reach indigenous peoples on the same scale as in the rest of the population. New sources of nationwide data on deaths in households, as in the case of the 2010 Census, can contribute to a better understanding of inequalities by color or race in Brazil.
Perceived Sources of Occupational Stress among Primary School Teachers in Delta State of Nigeria
ERIC Educational Resources Information Center
Akpochafo, G. O.
2012-01-01
This study investigated the most prevalent sources of occupational stress and also the demographic variables of gender, age and length of service among primary school teachers in Delta State. Two research questions and three hypotheses guided the study. The study used a descriptive survey design. The population was the primary school teachers in…
Discrete X-Ray Source Populations and Star Formation History in Nearby Galaxies
NASA Technical Reports Server (NTRS)
Zezas, Andreas; Hasan, Hashima (Technical Monitor)
2005-01-01
This program aims in understanding the connection between the discrete X-ray source populations observed in nearby galaxies and the history of star-formation in these galaxies. The ultimate goal is to use this knowledge in order to constrain X-ray binary evolution channels. For this reason although the program is primarily observational it has a significant modeling component. During the second year of this study we focused on detailed studies of the Antennae galaxies and the Small Magellanic Cloud (SMC). We also performed the initial analysis of the 5 galaxies forming a starburst-age sequence.
ERIC Educational Resources Information Center
Carpenter, Dick M., II; Clayton, Grant
2014-01-01
Using confirmatory factor analysis, this study examines the validity of the Usher and Pajares Sources of Self-Efficacy in Mathematics (SSEM) for prospective or eventual first-generation college students while still in middle school, a population not studied with the SSEM heretofore. Studying this population is especially noteworthy as educators…
Pregnant & Lactating Populations Research - NCS Dietary Assessment Literature Review
Identifying and studying additional biomarkers of energy and nutrient intake will advance validation efforts and lead to a better understanding of the biases and sources of measurement error in dietary assessment instruments in pregnant or lactating populations.
Pratt, Gregory C.; Vadali, Monika L.; Kvale, Dorian L.; Ellickson, Kristie M.
2015-01-01
Higher levels of nearby traffic increase exposure to air pollution and adversely affect health outcomes. Populations with lower socio-economic status (SES) are particularly vulnerable to stressors like air pollution. We investigated cumulative exposures and risks from traffic and from MNRiskS-modeled air pollution in multiple source categories across demographic groups. Exposures and risks, especially from on-road sources, were higher than the mean for minorities and low SES populations and lower than the mean for white and high SES populations. Owning multiple vehicles and driving alone were linked to lower household exposures and risks. Those not owning a vehicle and walking or using transit had higher household exposures and risks. These results confirm for our study location that populations on the lower end of the socio-economic spectrum and minorities are disproportionately exposed to traffic and air pollution and at higher risk for adverse health outcomes. A major source of disparities appears to be the transportation infrastructure. Those outside the urban core had lower risks but drove more, while those living nearer the urban core tended to drive less but had higher exposures and risks from on-road sources. We suggest policy considerations for addressing these inequities. PMID:25996888
Source-to-exposure assessment with the Pangea multi-scale framework - case study in Australia.
Wannaz, Cedric; Fantke, Peter; Lane, Joe; Jolliet, Olivier
2018-01-24
Effective planning of airshed pollution mitigation is often constrained by a lack of integrative analysis able to relate the relevant emitters to the receptor populations at risk. Both emitter and receptor perspectives are therefore needed to consistently inform emission and exposure reduction measures. This paper aims to extend the Pangea spatial multi-scale multimedia framework to evaluate source-to-receptor relationships of industrial sources of organic pollutants in Australia. Pangea solves a large compartmental system in parallel by block to determine arrays of masses at steady-state for 100 000+ compartments and 4000+ emission scenarios, and further computes population exposure by inhalation and ingestion. From an emitter perspective, radial spatial distributions of population intakes show high spatial variation in intake fractions from 0.68 to 33 ppm for benzene, and from 0.006 to 9.5 ppm for formaldehyde, contrasting urban, rural, desert, and sea source locations. Extending analyses to the receptor perspective, population exposures from the combined emissions of 4101 Australian point sources are more extended for benzene that travels over longer distances, versus formaldehyde that has a more local impact. Decomposing exposure per industrial sector shows petroleum and steel industry as the highest contributing industrial sectors for benzene, whereas the electricity sector and petroleum refining contribute most to formaldehyde exposures. The source apportionment identifies the main sources contributing to exposure at five locations. Overall, this paper demonstrates high interest in addressing exposures from both an emitter perspective well-suited to inform product oriented approaches such as LCA, and from a receptor perspective for health risk mitigation.
Massey, Philip M; Langellier, Brent A; Sentell, Tetine; Manganello, Jennifer
2017-12-01
To examine differences in health information seeking between U.S.-born and foreign-born populations in the U.S. Data from 2008 to 2014 from the Health Information National Trends Survey were used in this study (n = 15,249). Bivariate analyses, logistic regression, and predicted probabilities were used to examine health information seeking and sources of health information. Findings demonstrate that 59.3% of the Hispanic foreign-born population reported looking for health information, fewer than other racial/ethnic groups in the sample. Compared with non-Hispanic White, non-Hispanic Black (OR = 0.62) and Hispanic foreign-born individuals (OR = 0.31) were the least likely to use the internet as a first source for health information. Adjustment for language preference explains much of the disparity in health information seeking between the Hispanic foreign-born population and Whites; controlling for nativity, respondents who prefer Spanish have 0.25 the odds of using the internet as a first source of health information compared to those who prefer English. Foreign-born nativity and language preference are significant determinants of health information seeking. Further research is needed to better understand how information seeking patterns can influence health care use, and ultimately health outcomes. To best serve diverse racial and ethnic minority populations, health care systems, health care providers, and public health professionals must provide culturally competent health information resources to strengthen access and use by vulnerable populations, and to ensure that all populations are able to benefit from evolving health information sources in the digital age.
Baliatsas, Christos; van Kamp, Irene; van Poll, Ric; Yzermans, Joris
2016-07-01
A systematic review of observational studies was conducted to assess the association between everyday life low-frequency noise (LFN) components, including infrasound and health effects in the general population. Literature databases Pubmed, Embase and PsycInfo and additional bibliographic sources such as reference sections of key publications and journal databases were searched for peer-reviewed studies published from 2000 to 2015. Seven studies met the inclusion criteria. Most of them examined subjective annoyance as primary outcome. The adequacy of provided information in the included papers and methodological quality of studies was also addressed. Moreover, studies were screened for meta-analysis eligibility. Some associations were observed between exposure to LFN and annoyance, sleep-related problems, concentration difficulties and headache in the adult population living in the vicinity of a range of LFN sources. However, evidence, especially in relation to chronic medical conditions, was very limited. The estimated pooled prevalence of high subjective annoyance attributed to LFN was about 10%. Epidemiological research on LFN and health effects is scarce and suffers from methodological shortcomings. Low frequency noise in the everyday environment constitutes an issue that requires more research attention, particularly for people living in the vicinity of relevant sources. Copyright © 2016 Elsevier B.V. All rights reserved.
Mepham, Nick; Bouman, Walter P; Arcelus, Jon; Hayter, Mark; Wylie, Kevan R
2014-12-01
There is a scarcity of research into the use of non-physician-sourced cross-sex hormones in the transgender population. However, when medication is not prescribed by health professionals, users' knowledge of such medication may be adversely affected. This study aims to define the prevalence of Internet-sourced sex hormone use in a population attending for initial assessment at a gender identity clinic, to compare the prevalence between gender-dysphoric men and women, and to compare knowledge of cross-sex hormone side effects between users who source cross-sex hormones from medical doctors and those who source them elsewhere. In the first part of the study, a cross-sectional design is used to measure the overall prevalence of sex hormone use among individuals referred to a gender clinic. The second part is a questionnaire survey aiming at measuring sex hormone knowledge among individuals referred to this clinic. Main outcome measures were (i) categorical data on the prevalence and source of cross-sex hormone use and (ii) knowledge of sex hormone side effects in a population referred to a gender clinic. Cross-sex hormone use was present in 23% of gender clinic referrals, of whom 70% sourced the hormones via the Internet. Trans men using testosterone had a sex hormone usage prevalence of 6%; one-third of users sourced it from the Internet. Trans women had a sex hormone usage prevalence of 32%; approximately 70% of users sourced hormones from the Internet. Cross-sex hormone users who sourced their hormones from physicians were more aware of side effects than those who used other sources to access hormones. One in four trans women self-prescribe cross-sex hormones before attending gender clinics, most commonly via the Internet. This practice is currently rare among trans men. Self-prescribing without medical advice leaves individuals without the knowledge required to minimize health risks. © 2014 International Society for Sexual Medicine.
Chemical and biological tracers to determine groundwater flow in karstic aquifer, Yucatan Peninsula
NASA Astrophysics Data System (ADS)
Lenczewski, M.; Leal-Bautista, R. M.; McLain, J. E.
2013-05-01
Little is known about the extent of pollution in groundwater in the Yucatan Peninsula; however current population growth, both from international tourism and Mexican nationals increases the potential for wastewater release of a vast array of contaminants including personal care products, pharmaceuticals (Rx), and pathogenic microorganisms. Pathogens and Rx in groundwater can persist and can be particularly acute in this region where high permeability of the karst bedrock and the lack of top soil permit the rapid transport of contaminants into groundwater aquifers. The objective of this research is to develop and utilize novel biological and chemical source tracking methods to distinguish between different sources of anthropogenic pollution in degraded groundwater. Although several methods have been used successfully to track fecal contamination sources in small scale studies, little is known about their spatial limitations, as source tracking studies rarely include sample collection over a wide geographical area and with different sources of water. In addition, although source tracking methods to distinguish human from animal fecal contamination are widely available, this work has developed source tracking distinguish between separate human populations is highly unique. To achieve this objective, we collected water samples from a series of drinking wells, cenotes (sinkholes), wastewater treatment plants, and injection wells across the Yucatan Peninsula and examine potential source tracers within the collected water samples. The result suggests that groundwater sources impacted by tourist vs. local populations contain different chemical stressors. This work has developed a more detailed understanding of the presence and persistence of personal care products, pharmaceuticals, and fecal indicators in a karstic system; such understanding will be a vital component for the protection Mexican groundwater and human health. Quantification of different pollution sources within groundwater samples identified point sources of pollution, identify potential remediation strategies, and contribute to an improved understanding of the environmental impact of tourism and tourism-generated waste products on this groundwater-dependent ecosystem.
Sexual Orientation and School Discipline: New Evidence from a Population-Based Sample
ERIC Educational Resources Information Center
Mittleman, Joel
2018-01-01
Sexual minorities' risk for exclusionary discipline is a commonly cited indicator of the challenges that these students face. The current study addresses this issue by introducing a new data source for research on sexual minority students: the Fragile Families and Childhood Wellbeing Study. In this geographically diverse, population-based sample,…
ERIC Educational Resources Information Center
Glisky, Elizabeth L.; Kong, Lauren L.
2008-01-01
Source memory has consistently been associated with prefrontal function in both normal and clinical populations. Nevertheless, the exact contribution of this brain region to source memory remains uncertain, and evidence suggests that processes used by young and older adults may differ. The authors explored the extent to which scores on composite…
Jenkins, Paul A; Song, Yun S; Brem, Rachel B
2012-01-01
Genetic exchange between isolated populations, or introgression between species, serves as a key source of novel genetic material on which natural selection can act. While detecting historical gene flow from DNA sequence data is of much interest, many existing methods can be limited by requirements for deep population genomic sampling. In this paper, we develop a scalable genealogy-based method to detect candidate signatures of gene flow into a given population when the source of the alleles is unknown. Our method does not require sequenced samples from the source population, provided that the alleles have not reached fixation in the sampled recipient population. The method utilizes recent advances in algorithms for the efficient reconstruction of ancestral recombination graphs, which encode genealogical histories of DNA sequence data at each site, and is capable of detecting the signatures of gene flow whose footprints are of length up to single genes. Further, we employ a theoretical framework based on coalescent theory to test for statistical significance of certain recombination patterns consistent with gene flow from divergent sources. Implementing these methods for application to whole-genome sequences of environmental yeast isolates, we illustrate the power of our approach to highlight loci with unusual recombination histories. By developing innovative theory and methods to analyze signatures of gene flow from population sequence data, our work establishes a foundation for the continued study of introgression and its evolutionary relevance.
Jenkins, Paul A.; Song, Yun S.; Brem, Rachel B.
2012-01-01
Genetic exchange between isolated populations, or introgression between species, serves as a key source of novel genetic material on which natural selection can act. While detecting historical gene flow from DNA sequence data is of much interest, many existing methods can be limited by requirements for deep population genomic sampling. In this paper, we develop a scalable genealogy-based method to detect candidate signatures of gene flow into a given population when the source of the alleles is unknown. Our method does not require sequenced samples from the source population, provided that the alleles have not reached fixation in the sampled recipient population. The method utilizes recent advances in algorithms for the efficient reconstruction of ancestral recombination graphs, which encode genealogical histories of DNA sequence data at each site, and is capable of detecting the signatures of gene flow whose footprints are of length up to single genes. Further, we employ a theoretical framework based on coalescent theory to test for statistical significance of certain recombination patterns consistent with gene flow from divergent sources. Implementing these methods for application to whole-genome sequences of environmental yeast isolates, we illustrate the power of our approach to highlight loci with unusual recombination histories. By developing innovative theory and methods to analyze signatures of gene flow from population sequence data, our work establishes a foundation for the continued study of introgression and its evolutionary relevance. PMID:23226196
High population variability and source-sink dynamics in a solitary bee species.
Franzén, Markus; Nilsson, Sven G
2013-06-01
Although solitary bees are considered to play key roles in ecosystem functions, surprisingly few studies have explored their population dynamics. We investigated the population dynamics of a rare, declining, solitary bee (Andrena humilis) in a landscape of 80 km2 in southern Sweden from 2003 to 2011. Only one population was persistent throughout all years studied; most likely this population supplied the surrounding landscape with 11 smaller, temporary local populations. Despite stable pollen availability, the size of the persistent population fluctuated dramatically in a two-year cycle over the nine years, with 490-1230 nests in odd-numbered years and 21-48 nests in even-numbered years. These fluctuations were not significantly related to climatic variables or pollen availability. Nineteen colonization and 14 extinction events were recorded. Occupancy decreased with distance from the persistent population and increased with increasing resource (pollen) availability. There were significant positive correlations between the size of the persistent population and patch occupancy and colonization. Colonizations were generally more common in patches closer to the persistent population, whereas extinctions were independent of distance from the persistent population. Our results highlight the complex population dynamics that exist for this solitary bee species, which could be due to source-sink dynamics, a prolonged diapause, or can represent a bet-hedging strategy to avoid natural enemies and survive in small habitat patches. If large fluctuations in solitary bee populations prove to be widespread, it will have important implications for interpreting ecological relationships, bee conservation, and pollination.
Identifying PM2.5 and PM0.1 sources for epidemiological studies in California.
Hu, Jianlin; Zhang, Hongliang; Chen, Shuhua; Ying, Qi; Wiedinmyer, Christine; Vandenberghe, Francois; Kleeman, Michael J
2014-05-06
The University of California-Davis_Primary (UCD_P) model was applied to simultaneously track ∼ 900 source contributions to primary particulate matter (PM) in California for seven continuous years (January 1st, 2000 to December 31st, 2006). Predicted source contributions to primary PM2.5 mass, PM1.8 elemental carbon (EC), PM1.8 organic carbon (OC), PM0.1 EC, and PM0.1 OC were in general agreement with the results from previous source apportionment studies using receptor-based techniques. All sources were further subjected to a constraint check based on model performance for PM trace elemental composition. A total of 151 PM2.5 sources and 71 PM0.1 sources contained PM elements that were predicted at concentrations in general agreement with measured values at nearby monitoring sites. Significant spatial heterogeneity was predicted among the 151 PM2.5 and 71 PM0.1 source concentrations, and significantly different seasonal profiles were predicted for PM2.5 and PM0.1 in central California vs southern California. Population-weighted concentrations of PM emitted from various sources calculated using the UCD_P model spatial information differed from the central monitor estimates by up to 77% for primary PM2.5 mass and 148% for PM2.5 EC because the central monitor concentration is not representative of exposure for nearby population. The results from the UCD_P model provide enhanced source apportionment information for epidemiological studies to examine the relationship between health effects and concentrations of primary PM from individual sources.
ERIC Educational Resources Information Center
Abouserie, Hossam M. R.
2008-01-01
The purpose of this study was to explore and investigate the ways faculty at The School of Information Studies at Syracuse University use Networked Information Sources and Services to support their service tasks. Library and Information Sciences faculty were chosen as the population for this study. The study aimed to answer the following…
Population demographics of two local South Carolina mourning dove populations
McGowan, D.P.; Otis, D.L.
1998-01-01
The mourning dove (Zenaida macroura) call-count index had a significant (P 2,300 doves and examined >6,000 individuals during harvest bag checks. An age-specific band recovery model with time- and area-specific recovery rates, and constant survival rates, was chosen for estimation via Akaike's Information Criterion (AIC), likelihood ratio, and goodness-of-fit criteria. After-hatching-year (AHY) annual survival rate was 0.359 (SE = 0.056), and hatching-year (HY) annual survival rate was 0.118 (SE = 0.042). Average estimated recruitment per adult female into the prehunting season population was 3.40 (SE = 1.25) and 2.32 (SE = 0.46) for the 2 study areas. Our movement data support earlier hypotheses of nonmigratory breeding and harvested populations in South Carolina. Low survival rates and estimated population growth rate in the study areas may be representative only of small-scale areas that are heavily managed for dove hunting. Source-sink theory was used to develop a model of region-wide populations that is composed of source areas with positive growth rates and sink areas of declining growth. We suggest management of mourning doves in the Southeast might benefit from improved understanding of local population dynamics, as opposed to regional-scale population demographics.
2013-01-01
Numerous quantitative PCR assays for microbial fecal source tracking (MST) have been developed and evaluated in recent years. Widespread application has been hindered by a lack of knowledge regarding the geographical stability and hence applicability of such methods beyond the regional level. This study assessed the performance of five previously reported quantitative PCR assays targeting human-, cattle-, or ruminant-associated Bacteroidetes populations on 280 human and animal fecal samples from 16 countries across six continents. The tested cattle-associated markers were shown to be ruminant-associated. The quantitative distributions of marker concentrations in target and nontarget samples proved to be essential for the assessment of assay performance and were used to establish a new metric for quantitative source-specificity. In general, this study demonstrates that stable target populations required for marker-based MST occur around the globe. Ruminant-associated marker concentrations were strongly correlated with total intestinal Bacteroidetes populations and with each other, indicating that the detected ruminant-associated populations seem to be part of the intestinal core microbiome of ruminants worldwide. Consequently tested ruminant-targeted assays appear to be suitable quantitative MST tools beyond the regional level while the targeted human-associated populations seem to be less prevalent and stable, suggesting potential for improvements in human-targeted methods. PMID:23755882
Phylogenetic Diversity and Membership Patterns of Fecal and Environmental Bacteroidales Populations
Members of the Bacteroidales order have recently been targets of microbial source tracking assays. While several studies have documented that some populations exhibit preferential host-distribution, given the vast diversity of this bacterial group, it is still necessary to resolv...
Major sources of benzene exposure.
Wallace, L A
1989-01-01
Data from EPA's TEAM Study allow us to identify the major sources of exposure to benzene for much of the U.S. population. These sources turn out to be quite different from what had previously been considered the important sources. The most important source of exposure for 50 million smokers is the mainstream smoke from their cigarettes, which accounts for about half of the total population burden of exposure to benzene. Another 20% of nationwide exposure is contributed by various personal activities, such as driving and using attached garages. (Emissions from consumer products, building materials, paints, and adhesives may also be important, although data are largely lacking.) The traditional sources of atmospheric emissions (auto exhaust and industrial emissions) account for only about 20% of total exposure. Environmental tobacco smoke is an important source, accounting for about 5% of total nationwide exposure. A number of sources sometimes considered important, such as petroleum refining operations, petrochemical manufacturing, oil storage tanks, urban-industrial areas, service stations, certain foods, groundwater contamination, and underground gasoline leaks, appear to be unimportant on a nationwide basis. PMID:2477239
Density estimation in tiger populations: combining information for strong inference
Gopalaswamy, Arjun M.; Royle, J. Andrew; Delampady, Mohan; Nichols, James D.; Karanth, K. Ullas; Macdonald, David W.
2012-01-01
A productive way forward in studies of animal populations is to efficiently make use of all the information available, either as raw data or as published sources, on critical parameters of interest. In this study, we demonstrate two approaches to the use of multiple sources of information on a parameter of fundamental interest to ecologists: animal density. The first approach produces estimates simultaneously from two different sources of data. The second approach was developed for situations in which initial data collection and analysis are followed up by subsequent data collection and prior knowledge is updated with new data using a stepwise process. Both approaches are used to estimate density of a rare and elusive predator, the tiger, by combining photographic and fecal DNA spatial capture–recapture data. The model, which combined information, provided the most precise estimate of density (8.5 ± 1.95 tigers/100 km2 [posterior mean ± SD]) relative to a model that utilized only one data source (photographic, 12.02 ± 3.02 tigers/100 km2 and fecal DNA, 6.65 ± 2.37 tigers/100 km2). Our study demonstrates that, by accounting for multiple sources of available information, estimates of animal density can be significantly improved.
Density estimation in tiger populations: combining information for strong inference.
Gopalaswamy, Arjun M; Royle, J Andrew; Delampady, Mohan; Nichols, James D; Karanth, K Ullas; Macdonald, David W
2012-07-01
A productive way forward in studies of animal populations is to efficiently make use of all the information available, either as raw data or as published sources, on critical parameters of interest. In this study, we demonstrate two approaches to the use of multiple sources of information on a parameter of fundamental interest to ecologists: animal density. The first approach produces estimates simultaneously from two different sources of data. The second approach was developed for situations in which initial data collection and analysis are followed up by subsequent data collection and prior knowledge is updated with new data using a stepwise process. Both approaches are used to estimate density of a rare and elusive predator, the tiger, by combining photographic and fecal DNA spatial capture-recapture data. The model, which combined information, provided the most precise estimate of density (8.5 +/- 1.95 tigers/100 km2 [posterior mean +/- SD]) relative to a model that utilized only one data source (photographic, 12.02 +/- 3.02 tigers/100 km2 and fecal DNA, 6.65 +/- 2.37 tigers/100 km2). Our study demonstrates that, by accounting for multiple sources of available information, estimates of animal density can be significantly improved.
Drinking Water Quality Status and Contamination in Pakistan
Nafees, Muhammad; Rizwan, Muhammad; Bajwa, Raees Ahmad; Shakoor, Muhammad Bilal; Arshad, Muhammad Umair; Chatha, Shahzad Ali Shahid; Deeba, Farah; Murad, Waheed; Malook, Ijaz
2017-01-01
Due to alarming increase in population and rapid industrialization, drinking water quality is being deteriorated day by day in Pakistan. This review sums up the outcomes of various research studies conducted for drinking water quality status of different areas of Pakistan by taking into account the physicochemical properties of drinking water as well as the presence of various pathogenic microorganisms. About 20% of the whole population of Pakistan has access to safe drinking water. The remaining 80% of population is forced to use unsafe drinking water due to the scarcity of safe and healthy drinking water sources. The primary source of contamination is sewerage (fecal) which is extensively discharged into drinking water system supplies. Secondary source of pollution is the disposal of toxic chemicals from industrial effluents, pesticides, and fertilizers from agriculture sources into the water bodies. Anthropogenic activities cause waterborne diseases that constitute about 80% of all diseases and are responsible for 33% of deaths. This review highlights the drinking water quality, contamination sources, sanitation situation, and effects of unsafe drinking water on humans. There is immediate need to take protective measures and treatment technologies to overcome unhygienic condition of drinking water supplies in different areas of Pakistan. PMID:28884130
Drinking Water Quality Status and Contamination in Pakistan.
Daud, M K; Nafees, Muhammad; Ali, Shafaqat; Rizwan, Muhammad; Bajwa, Raees Ahmad; Shakoor, Muhammad Bilal; Arshad, Muhammad Umair; Chatha, Shahzad Ali Shahid; Deeba, Farah; Murad, Waheed; Malook, Ijaz; Zhu, Shui Jin
2017-01-01
Due to alarming increase in population and rapid industrialization, drinking water quality is being deteriorated day by day in Pakistan. This review sums up the outcomes of various research studies conducted for drinking water quality status of different areas of Pakistan by taking into account the physicochemical properties of drinking water as well as the presence of various pathogenic microorganisms. About 20% of the whole population of Pakistan has access to safe drinking water. The remaining 80% of population is forced to use unsafe drinking water due to the scarcity of safe and healthy drinking water sources. The primary source of contamination is sewerage (fecal) which is extensively discharged into drinking water system supplies. Secondary source of pollution is the disposal of toxic chemicals from industrial effluents, pesticides, and fertilizers from agriculture sources into the water bodies. Anthropogenic activities cause waterborne diseases that constitute about 80% of all diseases and are responsible for 33% of deaths. This review highlights the drinking water quality, contamination sources, sanitation situation, and effects of unsafe drinking water on humans. There is immediate need to take protective measures and treatment technologies to overcome unhygienic condition of drinking water supplies in different areas of Pakistan.
Saville, Amanda; Charles, Melodi; Chavan, Suchitra; Muñoz, Miguel; Gómez-Alpizar, Luis; Ristaino, Jean Beagle
2017-12-01
Pseudocercospora fijiensis is the causal pathogen of black Sigatoka, a devastating disease of banana that can cause 20 to 80% yield loss in the absence of fungicides in banana crops. The genetic structure of populations of P. fijiensis in Costa Rica was examined and compared with Honduran and global populations to better understand migration patterns and inform management strategies. In total, 118 isolates of P. fijiensis collected from Costa Rica and Honduras from 2010 to 2014 were analyzed using multilocus genotyping of six loci and compared with a previously published global dataset of populations of P. fijiensis. The Costa Rican and Honduran populations shared haplotype diversity with haplotypes from Southeast Asia, Oceania, and the Americas but not Africa for all but one of the six loci studied. Gene flow and shared haplotype diversity was found in Honduran and Costa Rican populations of the pathogen. The data indicate that the haplotypic diversity observed in Costa Rican populations of P. fijiensis is derived from dispersal from initial outbreak sources in Honduras and admixtures between genetically differentiated sources from Southeast Asia, Oceania, and the Americas.
The role of ancestry in TB susceptibility of an admixed South African population.
Daya, Michelle; van der Merwe, Lize; van Helden, Paul D; Möller, Marlo; Hoal, Eileen G
2014-07-01
Genetic susceptibility to tuberculosis (TB) has been well established and this, taken together with variation in susceptibility observed between different geographic and ethnic populations, implies that susceptibility to TB may in part be affected by ethnicity. In a previous genome-wide TB case-control study (642 cases and 91 controls) of the admixed South African Coloured (SAC) population, we found a positive correlation between African San ancestry and TB susceptibility, and negative correlations with European and Asian ancestries. Since genome-wide data was available for only a small number of controls in the previous study, we endeavored to validate this finding by genotyping a panel of ancestry informative markers (AIMs) in additional individuals, yielding a data set of 918 cases and 507 controls. Ancestry proportions were estimated using the AIMs for each of the source populations of the SAC (African San, African non-San, European, South Asian and East Asian). Using logistic regression models to test for association between TB and ancestry, we confirmed the substantial effect of ancestry on TB susceptibility. We also investigated the effect of adjusting for ancestry in candidate gene TB association studies of the SAC. We report a polymorphism that is no longer significantly associated with TB after adjustment for ancestry, a polymorphism that is significantly associated with TB only after adjustment for ancestry, and a polymorphism where the association significance remains unchanged. By comparing the allele frequencies of these polymorphisms in the source populations of the SAC, we demonstrate that association results are likely to be affected by adjustment for ancestry if allele frequencies differ markedly in the source populations of the SAC. Copyright © 2014 Elsevier Ltd. All rights reserved.
Himsworth, Chelsea G; Jardine, Claire M; Parsons, Kirbee L; Feng, Alice Y T; Patrick, David M
2014-01-01
Norway and black rats (Rattus norvegicus and Rattus rattus) are among the most ubiquitous urban wildlife species and are the source of a number of zoonotic diseases responsible for significant human morbidity and mortality in cities around the world. Rodent ecology is a primary determinant of the dynamics of zoonotic pathogens in rodent populations and the risk of pathogen transmission to people, yet many studies of rat-associated zoonoses do not account for the ecological characteristics of urban rat populations. This hinders the development of an in-depth understanding of the ecology of rat-associated zoonoses, limits comparability among studies, and can lead to erroneous conclusions. We conducted a year-long trapping-removal study to describe the ecological characteristics of urban rat populations in an inner-city neighborhood of Vancouver, Canada. The study focused on factors that might influence the ecology of zoonotic pathogens in these populations and/or our understanding of that ecology. We found that rat population density varied remarkably over short geographical distances, which could explain observed spatial distributions of rat-associated zoonoses and have implications for sampling and data analysis during research and surveillance. Season appeared to influence rat population composition even within the urban environment, which could cause temporal variation in pathogen prevalence. Body mass and bite wounds, which are often used in epidemiologic analyses as simple proxies for age and aggression, were shown to be more complex than previously thought. Finally, we found that factors associated with trapping can determine the size and composition of sampled rat population, and thus influence inferences made about the source population. These findings may help guide future studies of rats and rat-associated zoonoses.
Himsworth, Chelsea G.; Jardine, Claire M.; Parsons, Kirbee L.; Feng, Alice Y. T.; Patrick, David M.
2014-01-01
Norway and black rats (Rattus norvegicus and Rattus rattus) are among the most ubiquitous urban wildlife species and are the source of a number of zoonotic diseases responsible for significant human morbidity and mortality in cities around the world. Rodent ecology is a primary determinant of the dynamics of zoonotic pathogens in rodent populations and the risk of pathogen transmission to people, yet many studies of rat-associated zoonoses do not account for the ecological characteristics of urban rat populations. This hinders the development of an in-depth understanding of the ecology of rat-associated zoonoses, limits comparability among studies, and can lead to erroneous conclusions. We conducted a year-long trapping-removal study to describe the ecological characteristics of urban rat populations in an inner-city neighborhood of Vancouver, Canada. The study focused on factors that might influence the ecology of zoonotic pathogens in these populations and/or our understanding of that ecology. We found that rat population density varied remarkably over short geographical distances, which could explain observed spatial distributions of rat-associated zoonoses and have implications for sampling and data analysis during research and surveillance. Season appeared to influence rat population composition even within the urban environment, which could cause temporal variation in pathogen prevalence. Body mass and bite wounds, which are often used in epidemiologic analyses as simple proxies for age and aggression, were shown to be more complex than previously thought. Finally, we found that factors associated with trapping can determine the size and composition of sampled rat population, and thus influence inferences made about the source population. These findings may help guide future studies of rats and rat-associated zoonoses. PMID:24646877
NASA Astrophysics Data System (ADS)
Sharp, Martin; Parkes, John; Cragg, Barry; Fairchild, Ian J.; Lamb, Helen; Tranter, Martyn
1999-02-01
Bacterial populations found in subglacial meltwaters and basal ice are comparable to those in the active layer of permafrost and orders of magnitude larger than those found in ice cores from large ice sheets. Populations increase with sediment concentration, and 5% 24% of the bacteria are dividing or have just divided, suggesting that the populations are active. These findings (1) support inferences from recent studies of basal ice and meltwater chemistry that microbially mediated redox reactions may be important at glacier beds, (2) challenge the view that chemical weathering in glacial environments arises from purely inorganic reactions, and (3) raise the possibilities that redox reactions are a major source of protons consumed in subglacial weathering and that these reactions may be the dominant proton source beneath ice sheets where meltwaters are isolated from an atmospheric source of CO2. Microbial mediation may increase the rate of sulfide oxidation under subglacial conditions, a suggestion supported by the results of simple weathering experiments. If subglacial bacterial populations can oxidize and ferment organic carbon, it is important to reconsider the fate of soil organic carbon accumulated under interglacial conditions in areas subsequently overridden by Pleistocene ice sheets.
USDA-ARS?s Scientific Manuscript database
Insects are increasingly being recognized not only as a source of food to feed the ever growing world population but also as potential sources of new products and therapeutic agents, among which are sterols. In this study, we sought to profile sterols and their derivatives present in the desert locu...
Analysis on a diffusive SIS epidemic model with logistic source
NASA Astrophysics Data System (ADS)
Li, Bo; Li, Huicong; Tong, Yachun
2017-08-01
In this paper, we are concerned with an SIS epidemic reaction-diffusion model with logistic source in spatially heterogeneous environment. We first discuss some basic properties of the parabolic system, including the uniform upper bound of solutions and global stability of the endemic equilibrium when spatial environment is homogeneous. Our primary focus is to determine the asymptotic profile of endemic equilibria (when exist) if the diffusion (migration) rate of the susceptible or infected population is small or large. Combined with the results of Li et al. (J Differ Equ 262:885-913, 2017) where the case of linear source is studied, our analysis suggests that varying total population enhances persistence of infectious disease.
Vicky J. Erickson; Nancy L. Mandel; Frank C. Sorensen
2004-01-01
Source-related phenotypic variance was investigated in a common garden study of populations of Elymus glaucus Buckley (blue wildrye) from the Blue Mountain Ecological Province of northeastern Oregon and adjoining Washington. The primary objective of this study was to assess geographic patterns of potentially adaptive differentiation in this self-...
A review of population data utilization in beef cattle research.
Jones, R; Langemeier, M
2010-04-01
Controlled experimentation has been the most common source of research data in most biological sciences. However, many research questions lend themselves to the use of population data, or combinations of population data and data resulting from controlled experimentation. Studies of important economic outcomes, such as efficiency, profits, and costs, lend themselves particularly well to this type of analysis. Analytical methods that have been most commonly applied to population data in studies related to livestock production and management include statistical regression and mathematical programming. In social sciences, such as applied economics, it has become common to utilize more than one method in the same study to provide answers to the various questions at hand. Of course, care must be taken to ensure that the methods of analysis are appropriately applied; however, a wide variety of beef industry research questions are being addressed using population data. Issues related to data sources, aggregation levels, and consistency of collection often surface when using population data. These issues are addressed by careful consideration of the questions being addressed and the costs of data collection. Previous research across a variety of cattle production and marketing issues provides a broad foundation upon which to build future research. There is tremendous opportunity for increased use of population data and increased collaboration across disciplines to address issues of importance to the cattle industry.
Stochastic recruitment leads to symmetry breaking in foraging populations
NASA Astrophysics Data System (ADS)
Biancalani, Tommaso; Dyson, Louise; McKane, Alan
2014-03-01
When an ant colony is faced with two identical equidistant food sources, the foraging ants are found to concentrate more on one source than the other. Analogous symmetry-breaking behaviours have been reported in various population systems, (such as queueing or stock market trading) suggesting the existence of a simple universal mechanism. Past studies have neglected the effect of demographic noise and required rather complicated models to qualitatively reproduce this behaviour. I will show how including the effects of demographic noise leads to a radically different conclusion. The symmetry-breaking arises solely due to the process of recruitment and ceases to occur for large population sizes. The latter fact provides a testable prediction for a real system.
[Use of blood lead data to evaluate and prevent childhood lead poisoning in Latin America].
Romieu, Isabelle
2003-01-01
Exposure to lead is a widespread and serious threat to the health of children in Latin America. Health officials should monitor sources of exposure and health outcomes to design, implement, and evaluate prevention and control activities. To evaluate the magnitude of lead as a public health problem, three key elements must be defined: I) the potential sources of exposure, 2) the indicators to evaluate health effects and environmental exposure, and 3) the sampling methods for the population at risk. Several strategies can be used to select the study population depending on the study objectives, the time limitations, and the available resources. If the objective is to evaluate the magnitude and sources of the problem, the following sampling methods can be used: I) population-based random sampling; 2) facility-based random sampling within hospitals, daycare centers, or schools; 3) target sampling of high risk groups; 4) convenience sampling of volunteers; and 5) case reporting (which can lead to the identification of populations at risk and sources of exposures). For all sampling methods, information gathering should include the use of a questionnaire to collect general information on the participants and on potential local sources of exposure, as well as the collection of biological samples. In interpreting data, one should consider the type of sampling used and the non-response rates, as well as factors that might influence blood lead measurements, such as age and seasonal variability. Blood lead measurements should be integrated in an overall strategy to prevent lead toxicity in children. The English version of this paper is available at: http://www.insp.mx/salud/index.html.
Predicting local adaptation in fragmented plant populations: implications for restoration genetics
Pickup, Melinda; Field, David L; Rowell, David M; Young, Andrew G
2012-01-01
Understanding patterns and correlates of local adaptation in heterogeneous landscapes can provide important information in the selection of appropriate seed sources for restoration. We assessed the extent of local adaptation of fitness components in 12 population pairs of the perennial herb Rutidosis leptorrhynchoides (Asteraceae) and examined whether spatial scale (0.7–600 km), environmental distance, quantitative (QST) and neutral (FST) genetic differentiation, and size of the local and foreign populations could predict patterns of adaptive differentiation. Local adaptation varied among populations and fitness components. Including all population pairs, local adaptation was observed for seedling survival, but not for biomass, while foreign genotype advantage was observed for reproduction (number of inflorescences). Among population pairs, local adaptation increased with QST and local population size for biomass. QST was associated with environmental distance, suggesting ecological selection for phenotypic divergence. However, low FST and variation in population structure in small populations demonstrates the interaction of gene flow and drift in constraining local adaptation in R. leptorrhynchoides. Our study indicates that for species in heterogeneous landscapes, collecting seed from large populations from similar environments to candidate sites is likely to provide the most appropriate seed sources for restoration. PMID:23346235
Spitzer observations of NGC 2264: the nature of the disk population
NASA Astrophysics Data System (ADS)
Teixeira, P. S.; Lada, C. J.; Marengo, M.; Lada, E. A.
2012-04-01
Aims: NGC 2264 is a young cluster with a rich circumstellar disk population which makes it an ideal target for studying the evolution of stellar clusters. Our goal is to study the star formation history of NGC 2264 and to analyse the primordial disk evolution of its members. Methods: The study presented is based on data obtained with the Infrared Array Camera (IRAC) and the Multiband Imaging Photometer for Spitzer (MIPS) on board the Spitzer Space Telescope, combined with deep near-infrared (NIR) ground-based FLAMINGOS imaging and previously published optical data. Results: We build NIR dust extinction maps of the molecular cloud associated with the cluster, and determine it to have a mass of 2.1 × 103 M⊙ above an AV of 7 mag. Using a differential Ks-band luminosity function (KLF) of the cluster, we estimate the size of the population of NGC 2264, within the area observed by FLAMINGOS, to be 1436 ± 242 members. The star formation efficiency is ≥ ~25%. We identify the disk population and divide it into 3 groups based on their spectral energy distribution slopes from 3.6 μm to 8 μm and on the 24 μm excess emission: (i) optically thick inner disks, (ii) anaemic inner disks, and (iii) disks with inner holes, or transition disks. We analyse the spatial distribution of these sources and find that sources with thick disks segregate into sub-clusterings, whereas sources with anaemic disks do not. Furthermore, sources with anaemic disks are found to be unembedded (i.e., with AV < 3 mag), whereas the clustered sources with thick disks are still embedded within the parental cloud. Conclusions: NGC 2264 has undergone more than one star-forming event, where the anaemic and extincted thick disk population appear to have formed in separate episodes: the sources with anaemic disks are more evolved and have had time to disperse and populate a halo of the cluster. We also find tentative evidence of triggered star-formation in the Fox Fur Nebula. In terms of disk evolution, our findings support the emerging disk evolution paradigm of two distinct evolutionary paths for primordial optically thick disks: a homologous one where the disk emission decreases uniformly at NIR and mid-infrared (MIR) wavelengths, and a radially differential one where the emission from the inner region of the disk decreases more rapidly than from the outer region (forming transition disks).
Wang, Jianan; Fernández-Pavía, Sylvia P; Larsen, Meredith M; Garay-Serrano, Edith; Gregorio-Cipriano, Rosario; Rodríguez-Alvarado, Gerardo; Grünwald, Niklaus J; Goss, Erica M
2017-02-01
Globally destructive crop pathogens often emerge by migrating out of their native ranges. These pathogens are often diverse at their centre of origin and may exhibit adaptive variation in the invaded range via multiple introductions from different source populations. However, source populations are generally unidentified or poorly studied compared to invasive populations. Phytophthora infestans, the causal agent of late blight, is one of the most costly pathogens of potato and tomato worldwide. Mexico is the centre of origin and diversity of P. infestans and migration events out of Mexico have enormously impacted disease dynamics in North America and Europe. The debate over the origin of the pathogen, and population studies of P. infestans in Mexico, has focused on the Toluca Valley, whereas neighbouring regions have been little studied. We examined the population structure of P. infestans across central Mexico, including samples from Michoacán, Tlaxcala and Toluca. We found high levels of diversity consistent with sexual reproduction in Michoacán and Tlaxcala and population subdivision that was strongly associated with geographic region. We determined that population structure in central Mexico has contributed to diversity in introduced populations based on relatedness of U.S. clonal lineages to Mexican isolates from different regions. Our results suggest that P. infestans exists as a metapopulation in central Mexico, and this population structure could be contributing to the repeated re-emergence of P. infestans in the United States and elsewhere. © 2016 John Wiley & Sons Ltd.
The Modeling Environment for Total Risks studies (MENTOR) system, combined with an extension of the SHEDS (Stochastic Human Exposure and Dose Simulation) methodology, provide a mechanistically consistent framework for conducting source-to-dose exposure assessments of multiple pol...
A series of case studies is presented focusing on multimedia/multipathway population exposures to arsenic, employing the Population Based Modeling approach of the MENTOR (Modeling Environment for Total Risks) framework. This framework considers currently five exposure routes: i...
ASSESSING EXPOSURES TO MOBILE SOURCE AIR TOXIC EMISSIONS FOR POPULATIONS LIVING NEAR ROADWAYS
A growing number of epidemiological studies have identified an increase in occurrence of adverse health effects for populations living near major roads. However, the biological mechanism(s) leading to the adverse effects have not been identified. Limitations in exposure assessm...
Extending the Lincoln-Petersen estimator for multiple identifications in one source.
Köse, T; Orman, M; Ikiz, F; Baksh, M F; Gallagher, J; Böhning, D
2014-10-30
The Lincoln-Petersen estimator is one of the most popular estimators used in capture-recapture studies. It was developed for a sampling situation in which two sources independently identify members of a target population. For each of the two sources, it is determined if a unit of the target population is identified or not. This leads to a 2 × 2 table with frequencies f11 ,f10 ,f01 ,f00 indicating the number of units identified by both sources, by the first but not the second source, by the second but not the first source and not identified by any of the two sources, respectively. However, f00 is unobserved so that the 2 × 2 table is incomplete and the Lincoln-Petersen estimator provides an estimate for f00 . In this paper, we consider a generalization of this situation for which one source provides not only a binary identification outcome but also a count outcome of how many times a unit has been identified. Using a truncated Poisson count model, truncating multiple identifications larger than two, we propose a maximum likelihood estimator of the Poisson parameter and, ultimately, of the population size. This estimator shows benefits, in comparison with Lincoln-Petersen's, in terms of bias and efficiency. It is possible to test the homogeneity assumption that is not testable in the Lincoln-Petersen framework. The approach is applied to surveillance data on syphilis from Izmir, Turkey. Copyright © 2014 John Wiley & Sons, Ltd.
Global biodiversity monitoring: from data sources to essential biodiversity variables
Proenca, Vania; Martin, Laura J.; Pereira, Henrique M.; Fernandez, Miguel; McRae, Louise; Belnap, Jayne; Böhm, Monika; Brummitt, Neil; Garcia-Moreno, Jaime; Gregory, Richard D.; Honrado, Joao P; Jürgens, Norbert; Opige, Michael; Schmeller, Dirk S.; Tiago, Patricia; van Sway, Chris A
2016-01-01
Essential Biodiversity Variables (EBVs) consolidate information from varied biodiversity observation sources. Here we demonstrate the links between data sources, EBVs and indicators and discuss how different sources of biodiversity observations can be harnessed to inform EBVs. We classify sources of primary observations into four types: extensive and intensive monitoring schemes, ecological field studies and satellite remote sensing. We characterize their geographic, taxonomic and temporal coverage. Ecological field studies and intensive monitoring schemes inform a wide range of EBVs, but the former tend to deliver short-term data, while the geographic coverage of the latter is limited. In contrast, extensive monitoring schemes mostly inform the population abundance EBV, but deliver long-term data across an extensive network of sites. Satellite remote sensing is particularly suited to providing information on ecosystem function and structure EBVs. Biases behind data sources may affect the representativeness of global biodiversity datasets. To improve them, researchers must assess data sources and then develop strategies to compensate for identified gaps. We draw on the population abundance dataset informing the Living Planet Index (LPI) to illustrate the effects of data sources on EBV representativeness. We find that long-term monitoring schemes informing the LPI are still scarce outside of Europe and North America and that ecological field studies play a key role in covering that gap. Achieving representative EBV datasets will depend both on the ability to integrate available data, through data harmonization and modeling efforts, and on the establishment of new monitoring programs to address critical data gaps.
ERIC Educational Resources Information Center
Yazici, Hakki; Bulut, Ramazan; Yazici, Sibel
2016-01-01
In this study, it was aimed to determine the trust status of prospective social studies teachers regarding various knowledge sources related to nuclear energy and power stations regarded as a controversial socio-scientific issue and their perceptions on the possible risks and benefits of nuclear energy and power stations. Target population of the…
Ostro, Bart; Tobias, Aurelio; Querol, Xavier; Alastuey, Andrés; Amato, Fulvio; Pey, Jorge; Pérez, Noemí; Sunyer, Jordi
2011-12-01
Dozens of studies link acute exposure to particulate matter (PM) air pollution with premature mortality and morbidity, but questions remain about which species and sources in the vast PM mixture are responsible for the observed health effects. Although a few studies exist on the effects of species and sources in U.S. cities, European cities-which have a higher proportion of diesel engines and denser urban populations-have not been well characterized. Information on the effects of specific sources could aid in targeting pollution control and in articulating the biological mechanisms of PM. Our study examined the effects of various PM sources on daily mortality for 2003 through 2007 in Barcelona, a densely populated city in the northeast corner of Spain. Source apportionment for PM ≤ 2.5 μm and ≤ 10 µm in aerodynamic diameter (PM2.5 and PM10) using positive matrix factorization identified eight different factors. Case-crossover regression analysis was used to estimate the effects of each factor. Several sources of PM2.5, including vehicle exhaust, fuel oil combustion, secondary nitrate/organics, minerals, secondary sulfate/organics, and road dust, had statistically significant associations (p < 0.05) with all-cause and cardiovascular mortality. Also, in some cases relative risks for a respective interquartile range increase in concentration were higher for specific sources than for total PM2.5 mass. These results along with those from our multisource models suggest that traffic, sulfate from shipping and long-range transport, and construction dust are important contributors to the adverse health effects linked to PM.
Arraes, Maria Luisa Bezerra de Macedo; Holanda, Maísa Viana de; Lima, Luana Nepomuceno Gondim Costa; Sabadia, José Antônio Beltrão; Duarte, Cynthia Romariz; Almeida, Rosa Livia Freitas; Kendall, Carl; Kerr, Ligia Regina Sansigolo; Frota, Cristiane Cunha
2017-12-01
The detection of live Mycobacterium leprae in soil and animals other than humans suggests that the environment plays a role in the transmission of leprosy. The objective of this study was to investigate the presence of viable M. leprae in natural water sources used by the local population in five municipalities in the state of Ceará, northeastern Brazil. Samples were collected from 30 different sources. Viable bacilli were identified by reverse transcriptase polymerase chain reaction (PCR) of the M. leprae gyrA gene and sequencing of the PCR products. Physicochemical properties of each water source were also assessed. M. leprae gyrA mRNA was found in 23 (76.7%) of the water sources. No association was found between depth of the water and sample positivity, nor was there any association between the type of water used by the population and sample positivity. An association between viable M. leprae and temperature and pH was found. Georeferencing showed a relation between the residences of leprosy cases and water source containing the bacterium. The finding of viable M. leprae in natural water sources associated with human contact suggests that the environment plays an important role in maintaining endemic leprosy in the study region.
Estimating changes in urban land and urban population using refined areal interpolation techniques
NASA Astrophysics Data System (ADS)
Zoraghein, Hamidreza; Leyk, Stefan
2018-05-01
The analysis of changes in urban land and population is important because the majority of future population growth will take place in urban areas. U.S. Census historically classifies urban land using population density and various land-use criteria. This study analyzes the reliability of census-defined urban lands for delineating the spatial distribution of urban population and estimating its changes over time. To overcome the problem of incompatible enumeration units between censuses, regular areal interpolation methods including Areal Weighting (AW) and Target Density Weighting (TDW), with and without spatial refinement, are implemented. The goal in this study is to estimate urban population in Massachusetts in 1990 and 2000 (source zones), within tract boundaries of the 2010 census (target zones), respectively, to create a consistent time series of comparable urban population estimates from 1990 to 2010. Spatial refinement is done using ancillary variables such as census-defined urban areas, the National Land Cover Database (NLCD) and the Global Human Settlement Layer (GHSL) as well as different combinations of them. The study results suggest that census-defined urban areas alone are not necessarily the most meaningful delineation of urban land. Instead, it appears that alternative combinations of the above-mentioned ancillary variables can better depict the spatial distribution of urban land, and thus make it possible to reduce the estimation error in transferring the urban population from source zones to target zones when running spatially-refined temporal areal interpolation.
NASA Astrophysics Data System (ADS)
Zoraghein, H.; Leyk, S.; Balk, D.
2017-12-01
The analysis of changes in urban land and population is important because the majority of future population growth will take place in urban areas. The U.S. Census historically classifies urban land using population density and various land-use criteria. This study analyzes the reliability of census-defined urban lands for delineating the spatial distribution of urban population and estimating its changes over time. To overcome the problem of incompatible enumeration units between censuses, regular areal interpolation methods including Areal Weighting (AW) and Target Density Weighting (TDW), with and without spatial refinement, are implemented. The goal in this study is to estimate urban population in Massachusetts in 1990 and 2000 (source zones), within tract boundaries of the 2010 census (target zones), respectively, to create a consistent time series of comparable urban population estimates from 1990 to 2010. Spatial refinement is done using ancillary variables such as census-defined urban areas, the National Land Cover Database (NLCD) and the Global Human Settlement Layer (GHSL) as well as different combinations of them. The study results suggest that census-defined urban areas alone are not necessarily the most meaningful delineation of urban land. Instead it appears that alternative combinations of the above-mentioned ancillary variables can better depict the spatial distribution of urban land, and thus make it possible to reduce the estimation error in transferring the urban population from source zones to target zones when running spatially-refined temporal areal interpolation.
Ruiz-Herrera, Alfonso
2018-05-01
In this study, I explored the impact of constructing a new dispersal route between two different patches in a metapopulation. My results indicated that its success/failure on the population abundance greatly depends on the patches directly involved and negligibly on the network topology. Specifically, constructing a dispersal route is highly recommended if it connects a source to a source that is close to becoming a sink or a sink that is close to becoming a source. This biological property is the basis for understanding the influence of the network topology on the population abundance. According to some thresholds discussed in this manuscript, I identified when a given route has a positive or negative effect on the population size. Consequently, as a simple rule of thumb, managers should look for metapopulations that have the maximum (resp. minimum) number paths with a positive (resp. negative) effect on the population abundance. As emphasized, the biological results of this paper do not depend on the model formulation. Copyright © 2018 Elsevier Inc. All rights reserved.
Approximate Bayesian estimation of extinction rate in the Finnish Daphnia magna metapopulation.
Robinson, John D; Hall, David W; Wares, John P
2013-05-01
Approximate Bayesian computation (ABC) is useful for parameterizing complex models in population genetics. In this study, ABC was applied to simultaneously estimate parameter values for a model of metapopulation coalescence and test two alternatives to a strict metapopulation model in the well-studied network of Daphnia magna populations in Finland. The models shared four free parameters: the subpopulation genetic diversity (θS), the rate of gene flow among patches (4Nm), the founding population size (N0) and the metapopulation extinction rate (e) but differed in the distribution of extinction rates across habitat patches in the system. The three models had either a constant extinction rate in all populations (strict metapopulation), one population that was protected from local extinction (i.e. a persistent source), or habitat-specific extinction rates drawn from a distribution with specified mean and variance. Our model selection analysis favoured the model including a persistent source population over the two alternative models. Of the closest 750,000 data sets in Euclidean space, 78% were simulated under the persistent source model (estimated posterior probability = 0.769). This fraction increased to more than 85% when only the closest 150,000 data sets were considered (estimated posterior probability = 0.774). Approximate Bayesian computation was then used to estimate parameter values that might produce the observed set of summary statistics. Our analysis provided posterior distributions for e that included the point estimate obtained from previous data from the Finnish D. magna metapopulation. Our results support the use of ABC and population genetic data for testing the strict metapopulation model and parameterizing complex models of demography. © 2013 Blackwell Publishing Ltd.
Laboratory Colonisation and Genetic Bottlenecks in the Tsetse Fly Glossina pallidipes
Ciosi, Marc
2014-01-01
Background The IAEA colony is the only one available for mass rearing of Glossina pallidipes, a vector of human and animal African trypanosomiasis in eastern Africa. This colony is the source for Sterile Insect Technique (SIT) programs in East Africa. The source population of this colony is unclear and its genetic diversity has not previously been evaluated and compared to field populations. Methodology/Principal Findings We examined the genetic variation within and between the IAEA colony and its potential source populations in north Zimbabwe and the Kenya/Uganda border at 9 microsatellites loci to retrace the demographic history of the IAEA colony. We performed classical population genetics analyses and also combined historical and genetic data in a quantitative analysis using Approximate Bayesian Computation (ABC). There is no evidence of introgression from the north Zimbabwean population into the IAEA colony. Moreover, the ABC analyses revealed that the foundation and establishment of the colony was associated with a genetic bottleneck that has resulted in a loss of 35.7% of alleles and 54% of expected heterozygosity compared to its source population. Also, we show that tsetse control carried out in the 1990's is likely reduced the effective population size of the Kenya/Uganda border population. Conclusions/Significance All the analyses indicate that the area of origin of the IAEA colony is the Kenya/Uganda border and that a genetic bottleneck was associated with the foundation and establishment of the colony. Genetic diversity associated with traits that are important for SIT may potentially have been lost during this genetic bottleneck which could lead to a suboptimal competitiveness of the colony males in the field. The genetic diversity of the colony is lower than that of field populations and so, studies using colony flies should be interpreted with caution when drawing general conclusions about G. pallidipes biology. PMID:24551260
Wilson, R; Abbott, J H
2018-04-01
To describe the construction and preliminary validation of a new population-based microsimulation model developed to analyse the health and economic burden and cost-effectiveness of treatments for knee osteoarthritis (OA) in New Zealand (NZ). We developed the New Zealand Management of Osteoarthritis (NZ-MOA) model, a discrete-time state-transition microsimulation model of the natural history of radiographic knee OA. In this article, we report on the model structure, derivation of input data, validation of baseline model parameters against external data sources, and validation of model outputs by comparison of the predicted population health loss with previous estimates. The NZ-MOA model simulates both the structural progression of radiographic knee OA and the stochastic development of multiple disease symptoms. Input parameters were sourced from NZ population-based data where possible, and from international sources where NZ-specific data were not available. The predicted distributions of structural OA severity and health utility detriments associated with OA were externally validated against other sources of evidence, and uncertainty resulting from key input parameters was quantified. The resulting lifetime and current population health-loss burden was consistent with estimates of previous studies. The new NZ-MOA model provides reliable estimates of the health loss associated with knee OA in the NZ population. The model structure is suitable for analysis of the effects of a range of potential treatments, and will be used in future work to evaluate the cost-effectiveness of recommended interventions within the NZ healthcare system. Copyright © 2018 Osteoarthritis Research Society International. Published by Elsevier Ltd. All rights reserved.
Koistinen, Kimmo J; Edwards, Rufus D; Mathys, Patrick; Ruuskanen, Juhani; Künzli, Nino; Jantunen, Matti J
2004-01-01
This study assessed the source contributions to the mass concentrations of fine particles (PM2.5) in personal exposures and in residential indoor, residential outdoor, and workplace indoor microenvironments of the nonsmoking adult population unexposed to environmental tobacco smoke in Helsinki, Finland. The elemental composition of 48-hour personal exposure and residential indoor, residential outdoor, and workplace indoor PM2.5 was analyzed by energy-dispersive X-ray fluorescence spectrometry for 76 participants not exposed to environmental tobacco smoke and 102 participating residences with no smoking in Helsinki as a part of the EXPOLIS study. Subsequently, a principal component analysis was used to identify the emission sources of PM2.5-bound elements and black smoke in each microenvironment, and this information was used to identify the corresponding sources in personal exposures. Finally, source reconstruction was done to determine the relative contributions of each source type to the total PM2.5 mass concentrations. Inorganic secondary particles, primary combustion, and soil were the dominant source types for the PM2.5 mass concentration in all the microenvironments and personal exposures. The ratio of the residential indoor-to-outdoor PM2.5 concentration was close to unity, but the corresponding elemental ratios and source contributions varied. Resuspension of soil dust tracked indoors was a much larger contributor to residential and workplace indoor PM2.5 than soil dust to residential outdoor PM2.5. Source contributions to personal PM2.5 exposures were best approximated by data from residential and workplace indoor microenvironments. Population exposure assessment of PM2.5, based on outdoor fixed-site monitoring, overestimates exposures to outdoor sources like traffic and long-range transport and does not account for the contribution of significant indoor sources.
BARKER, BRITTANY S.; ANDONIAN, KRIKOR; SWOPE, SARAH M.; LUSTER, DOUGLAS G.; DLUGOSCH, KATRINA M.
2017-01-01
Identifying sources of genetic variation and reconstructing invasion routes for non-native introduced species is central to understanding the circumstances under which they may evolve increased invasiveness. In this study, we used genome-wide single nucleotide polymorphisms to study the colonization history of Centaurea solstitialis in its native range in Eurasia and invasions into the Americas. We leveraged this information to pinpoint key evolutionary shifts in plant size, a focal trait associated with invasiveness in this species. Our analyses revealed clear population genomic structure of potential source populations in Eurasia, including deep differentiation of a lineage found in the southern Apennine and Balkan Peninsulas and divergence among populations in Asia, eastern Europe, and western Europe. We found strongest support for an evolutionary scenario in which western European populations were derived from an ancient admixture event between populations from eastern Europe and Asia, and subsequently served as the main genetic ‘bridgehead’ for introductions to the Americas. Introductions to California appear to be from a single source region, and multiple, independent introductions of divergent genotypes likely occurred into the Pacific Northwest. Plant size has evolved significantly at three points during range expansion, including a large size increase in the lineage responsible for the aggressive invasion of California’s interior. These results reveal a long history of colonization, admixture, and trait evolution in C. solstitialis, and suggest routes for improving evidence-based management decisions for one of the most ecologically and economically damaging invasive species in the western United States. PMID:28029713
Olza, Josune; Aranceta-Bartrina, Javier; González-Gross, Marcela; Ortega, Rosa M; Serra-Majem, Lluis; Varela-Moreiras, Gregorio; Gil, Ángel
2017-02-21
Calcium, phosphorus, magnesium and vitamin D have important biological roles in the body, especially in bone metabolism. We aimed to study the reported intake, the disparity between the reported consumption and the level needed for adequacy and food sources of these four nutrients in the Spanish population. We assessed the reported intake for both, general population and plausible reporters. Results were extracted from the ANIBES survey, n = 2009. Three-day dietary reported intake data were obtained and misreporting was assessed according to the European Food Safety Authority (EFSA). Mean ± SEM (range) total reported consumption of calcium, phosphorus, magnesium, and vitamin D for the whole population were 698 ± 7 mg/day (71-2551 mg/day), 1176 ± 8 mg/day, (331-4429 mg/day), 222 ± 2 mg/day (73-782 mg/day), and 4.4 ± 0.1 µg/day (0.0-74.2 µg/day), respectively. In the whole group, 76% and 66%; 79% and 72%; and 94% and 93% of the population had reported intakes below 80% of the national and European recommended daily intakes for calcium, magnesium and vitamin D, respectively; these percentages were over 40% when the plausible reporters were analysed separately. The main food sources were milk and dairy products for calcium and phosphorus, cereals and grains for magnesium and fish for vitamin D. In conclusion, there is an important percentage of the Spanish ANIBES population not meeting the recommended intakes for calcium, magnesium and vitamin D.
Simulating deep surveys of the Galactic Plane with the Advanced Gamma-ray Imaging System (AGIS)
NASA Astrophysics Data System (ADS)
Funk, Stefan; Digel, Seth
2009-05-01
The pioneering survey of the Galactic plane by H.E.S.S., together with the northern complement now underway with VERITAS, has shown the inner Milky Way to be rich in TeV-emitting sources; new source classes have been found among the H.E.S.S. detections and unidentified sources remain. In order to explore optimizations of the design of an Advanced Gamma-ray Imaging System (AGIS)-like instrument for survey science, we constructed a model of the flux and size distributions of Galactic TeV sources, normalized to the H.E.S.S. sources but extrapolated to lower flux levels. We investigated potential outcomes from a survey with the order of magnitude improvement in sensitivity and attendant improvement in angular resolution planned for AGIS. Studies of individual sources and populations found with such a sensitivity survey will advance understanding of astrophysical particle acceleration, source populations, and even high-energy cosmic rays via detection of the low-level TeV diffuse emission in regions of high cosmic-ray densitiy.
Media Consumption and Population Characteristics of Political Opinion Leaders.
ERIC Educational Resources Information Center
Garrison, John P.; Andersen, Peter A.
This study examines the information sources and population characteristics that differentiate political opinion-leaders from nonleaders. A telephone poll of 339 subjects provided data indicating that political opinion leaders receive more information about candidates from all media, as well as through interpersonal communication, than do…
Jamin, C; Lachowsky, M
2015-10-01
In order to improve the understanding of hormonal contraceptive failures, this study evaluates the persistence of oral contraception and the use of emergency contraception (EC) during persistence incidents. We made the hypothesis of the existence of a strong link between the risk of unplanned pregnancies and these two parameters. In this study, we also evaluated women's perception of EC in order to elucidate the reasons of EC insufficient use. One survey was carried out on Internet on a representative sample of women, aged 16-45. In this survey, 3775 French women were interviewed (source-population). We defined a target population of 2415 fertile women who had heterosexual intercourse during the last 12 months, and a population of 760 women at risk of unintended pregnancy who had unprotected sexual intercourse during the last 12 months(risk-population). A little more than 30% of the target population, meaning 20% of the source-population (n=745) stopped their contraceptive method temporarily for an average time of two months. Almost 60% of women had a risk of unwanted pregnancy during this period without contraception, which is 59% of the risk-population. Only 20% of women among the population at risk used EC. The main reasons given for EC insufficient use were the misperception of the risk of pregnancy, the lack of knowledge about EC and its way of use. For the first time, this survey shows that 13% of women (of the source population) decide to stop temporarily their contraceptive method for an average time of two months per year. Fifty-nine percent of unplanned pregnancy situations are due to this poor contraception persistence. Although there is a need to reduce the risk of women being at risk, it seems also highly desirable to overcome the consequences of this poor persistence. Giving information about EC and a systematic prescription during contraception consultations would lead to an increased use of EC. Copyright © 2014 Elsevier Masson SAS. All rights reserved.
Cost and Usage Study of the Educational Resources Information Center (ERIC) System. Final Report.
ERIC Educational Resources Information Center
McDonald, Dennis D; And Others
A detailed descriptive analysis of both the direct and indirect costs incurred by the Federal government in operating the ERIC system, and the user population and user demand for ERIC products and services, this study is based on data gathered from a number of complementary sources. These sources included a survey of ERIC's U.S. intermediate…
ERIC Educational Resources Information Center
Heinmiller, Joseph L.
Based on data gathered from a number of complementary sources, this study provides a detailed descriptive analysis of both the direct and indirect costs incurred by the Federal government in operating the ERIC system, and the user population and user demand for ERIC products and services. Data sources included a survey of ERIC's U.S. intermediate…
ERIC Educational Resources Information Center
Lynn, Jerry R.; Gagnard, Alice
A study was conducted to examine message evaluations of selected public service advertisements (PSAs) by a young adult population and to test whether local and nonlocal source attribution would influence those evaluations. In addition, the study investigated the extent to which audience characteristics such as fatalism (the degree to which a…
Population Isolation in the Philippine War: A Case Study
2015-05-21
concentration camps appear as unnecessary and extremely harsh punishment. In one example of many, extreme charges of hostage taking, rape, and... torture from the Filipinos in Candelaria warranted an Army investigation.13 Secondary sources address environmental effects of population isolation...themselves targeted and potentially killed by the native forces.32 Public displays of these murders and assassinations meant to convince the population to
Ryou, Hyoung Gon; Heo, Jongbae; Kim, Sun-Young
2018-09-01
Studies of source apportionment (SA) for particulate matter (PM) air pollution have enhanced understanding of dominant pollution sources and quantification of their contribution. Although there have been many SA studies in South Korea over the last two decades, few studies provided an integrated understanding of PM sources nationwide. The aim of this study was to summarize findings of PM SA studies of South Korea and to explore study characteristics. We selected studies that estimated sources of PM 10 and PM 2.5 performed for 2000-2017 in South Korea using Positive Matrix Factorization and Chemical Mass Balance. We reclassified the original PM sources identified in each study into seven categories: motor vehicle, secondary aerosol, soil dust, biomass/field burning, combustion/industry, natural source, and others. These seven source categories were summarized by using frequency and contribution across four regions, defined by northwest, west, southeast, and southwest regions, by PM 10 and PM 2.5 . We also computed the population-weighted mean contribution of each source category. In addition, we compared study features including sampling design, sampling and lab analysis methods, chemical components, and the inclusion of Asian dust days. In the 21 selected studies, all six PM 10 studies identified motor vehicle, soil dust, and combustion/industry, while all 15 PM 2.5 studies identified motor vehicle and soil dust. Different from the frequency, secondary aerosol produced a large contribution to both PM 10 and PM 2.5 . Motor vehicle contributed highly to both, whereas the contribution of combustion/industry was high for PM 10 . The population-weighted mean contribution was the highest for the motor vehicle and secondary aerosol sources for both PM10 and PM2.5. However, these results were based on different subsets of chemical speciation data collected at a single sampling site, commonly in metropolitan areas, with short overlap and measured by different lab analysis methods. We found that motor vehicle and secondary aerosol were the most common and influential sources for PM in South Korea. Our study, however, suggested a caution to understand SA findings from heterogeneous study features for study designs and input data. Copyright © 2018. Published by Elsevier Ltd.
X-ray Binaries in the Central Region of M31
NASA Astrophysics Data System (ADS)
Trudolyubov, Sergey P.; Priedhorsky, W. C.; Cordova, F. A.
2006-09-01
We present the results of the systematic survey of X-ray sources in the central region of M31 using the data of XMM-Newton observations. The spectral properties and variability of 124 bright X-ray sources were studied in detail. We found that more than 80% of sources observed in two or more observations show significant variability on the time scales of days to years. At least 50% of the sources in our sample are spectrally variable. The fraction of variable sources in our survey is much higher than previously reported from Chandra survey of M31, and is remarkably close to the fraction of variable sources found in M31 globular cluster X-ray source population. We present spectral distribution of M31 X-ray sources, based on the spectral fitting with a power law model. The distribution of spectral photon index has two main peaks at 1.8 and 2.3, and shows clear evolution with source luminosity. Based on the similarity of the properties of M31 X-ray sources and their Galactic counterparts, we expect most of X-ray sources in our sample to be accreting binary systems with neutron star and black hole primaries. Combining the results of X-ray analysis (X-ray spectra, hardness-luminosity diagrams and variability) with available data at other wavelengths, we explore the possibility of distinguishing between bright neutron star and black hole binary systems, and identify 7% and 25% of sources in our sample as a probable black hole and neutron star candidates. Finally, we compare the M31 X-ray source population to the source populations of normal galaxies of different morphological type. Support for this work was provided through NASA Grant NAG5-12390. Part of this work was done during a summer workshop ``Revealing Black Holes'' at the Aspen Center for Physics, S. T. is grateful to the Center for their hospitality.
Assessment of port-related air quality impacts: geographic analysis of population
Increased global trade has led to greater transportation by rail, road and ships to move cargo. Based upon multiple near-road and near-source monitoring studies, the busy roadways and large emission sources at ports may impact local air quality within several hundred metres of th...
ERIC Educational Resources Information Center
Beck, David
This annotated bibliography identifies and describes documentary evidence of Chicago's American Indian population since the 1893 World's Columbian Exposition. Sources include studies and reports generated by Indian community organizations and agencies, community newsletters, newspapers, oral histories, grant applications, personal papers, and…
What's so special about chicken immunology?
USDA-ARS?s Scientific Manuscript database
What’s so special about chickens? Firstly, chickens are not only an invaluable model for studying immunology, they also provide the world’s main source of meat and will be a key protein source needed to feed the growing human population into the future. Poultry meat production is highly efficient ...
Anthropogenic emissions from a variety of sectors including mobile sources have decreased substantially over the past decades despite continued growth in population and economic activity. In this study, we analyze 1990-2010 trends in emission inventories, ambient observations and...
Carlson, Jane E.; Adams, Christopher A.; Holsinger, Kent E.
2016-01-01
Background and Aims Trait–environment relationships are commonly interpreted as evidence for local adaptation in plants. However, even when selection analyses support this interpretation, the mechanisms underlying differential benefits are often unknown. This study addresses this gap in knowledge using the broadly distributed South African shrub Protea repens. Specifically, the study examines whether broad-scale patterns of trait variation are consistent with spatial differences in selection and ecophysiology in the wild. Methods In a common garden study of plants sourced from 19 populations, associations were measured between five morphological traits and three axes describing source climates. Trait–trait and trait–environment associations were analysed in a multi-response model. Within two focal populations in the wild, selection and path analyses were used to test associations between traits, fecundity and physiological performance. Key Results Across 19 populations in a common garden, stomatal density increased with the source population’s mean annual temperature and decreased with its average amount of rainfall in midsummer. Concordantly, selection analysis in two natural populations revealed positive selection on stomatal density at the hotter, drier site, while failing to detect selection at the cooler, moister site. Dry-site plants with high stomatal density also had higher stomatal conductances, cooler leaf temperatures and higher light-saturated photosynthetic rates than those with low stomatal density, but no such relationships were present among wet-site plants. Leaf area, stomatal pore index and specific leaf area in the garden also co-varied with climate, but within-population differences were not associated with fitness in either wild population. Conclusions The parallel patterns of broad-scale variation, differences in selection and differences in trait–ecophysiology relationships suggest a mechanism for adaptive differentiation in stomatal density. Densely packed stomata may improve performance by increasing transpiration and cooling, but predominately in drier, hotter climates. This study uniquely shows context-dependent benefits of stomatal density – a trait rarely linked to local adaptation in plants. PMID:26424782
The Genetic Structure and History of Africans and African Americans
Tishkoff, Sarah A.; Reed, Floyd A.; Friedlaender, Françoise R.; Ehret, Christopher; Ranciaro, Alessia; Froment, Alain; Hirbo, Jibril B.; Awomoyi, Agnes A.; Bodo, Jean-Marie; Doumbo, Ogobara; Ibrahim, Muntaser; Juma, Abdalla T.; Kotze, Maritha J.; Lema, Godfrey; Moore, Jason H.; Mortensen, Holly; Nyambo, Thomas B.; Omar, Sabah A.; Powell, Kweli; Pretorius, Gideon S.; Smith, Michael W.; Thera, Mahamadou A.; Wambebe, Charles; Weber, James L.; Williams, Scott M.
2010-01-01
Africa is the source of all modern humans, but characterization of genetic variation and of relationships among populations across the continent has been enigmatic. We studied 121 African populations, four African American populations, and 60 non-African populations for patterns of variation at 1327 nuclear microsatellite and insertion/deletion markers. We identified 14 ancestral population clusters in Africa that correlate with self-described ethnicity and shared cultural and/or linguistic properties. We observed high levels of mixed ancestry in most populations, reflecting historical migration events across the continent. Our data also provide evidence for shared ancestry among geographically diverse hunter-gatherer populations (Khoesan speakers and Pygmies). The ancestry of African Americans is predominantly from Niger-Kordofanian (~71%), European (~13%), and other African (~8%) populations, although admixture levels varied considerably among individuals. This study helps tease apart the complex evolutionary history of Africans and African Americans, aiding both anthropological and genetic epidemiologic studies. PMID:19407144
Long Term Temporal and Spectral Evolution of Point Sources in Nearby Elliptical Galaxies
NASA Astrophysics Data System (ADS)
Durmus, D.; Guver, T.; Hudaverdi, M.; Sert, H.; Balman, Solen
2016-06-01
We present the results of an archival study of all the point sources detected in the lines of sight of the elliptical galaxies NGC 4472, NGC 4552, NGC 4649, M32, Maffei 1, NGC 3379, IC 1101, M87, NGC 4477, NGC 4621, and NGC 5128, with both the Chandra and XMM-Newton observatories. Specifically, we studied the temporal and spectral evolution of these point sources over the course of the observations of the galaxies, mostly covering the 2000 - 2015 period. In this poster we present the first results of this study, which allows us to further constrain the X-ray source population in nearby elliptical galaxies and also better understand the nature of individual point sources.
Light as an Energy Source in Continuous Cultures of Bacteriorhodopsin-Containing Halobacteria
Rodriguez-Valera, F.; Nieto, J. J.; Ruiz-Berraquero, F.
1983-01-01
The role of light as an energy source for slightly aereated cultures of halobacteria was studied, using continuous cultures with low nutrient concentrations and a low oxygen supply. A series of experiments were carried out with non-illuminated and differently illuminated cultures and with different oxygen transfer rates. Under low oxygen availability, light proved to be a decisively important energy source that allowed the populations to reach higher growth rates and much higher population densities. Oxygen influenced the growth over only a minimal level, below which neither the illuminated nor the dark cultures were affected by the oxygen transfer rate. From these results, it appears that the bacteriorhodopsin-mediated energy supply could have a very important role for the ecology of halobacteria in their microaerophilic habitats. In the illuminated cultures, cells that originated purple colonies on plates appeared. These cells, which could be bacteriorhodopsin-constitutive mutants, are now being studied. PMID:16346250
The invention of new approaches to DNA sequencing commonly referred to as next generation sequencing technologies is revolutionizing the study of microbial diversity. In this chapter, we discuss the characterization of microbial population structures in recreational waters and p...
Discrete X-Ray Source Populations and Star-Formation History in Nearby Galaxies
NASA Technical Reports Server (NTRS)
Zezas, Andreas
2004-01-01
This program aims in understanding the connection between the discrete X-ray source populations observed in nearby galaxies and the history of star-formation in these galaxies. The ultimate goal is to use this knowledge in order to constrain X-ray binary evolution channels. For this reason although the program is primarily observational it has a significant modeling component. During the first year of this study we focused on the definition of a pilot sample of galaxies with well know star-formation histories. A small part of this sample has already been observed and we performed initial analysis of the data. However, the majority of the objects in our sample either have not been observed at all, or the detection limit of the existing observations is not low enough to probe the bulk of their young X-ray binary populations. For this reason we successfully proposed for additional Chandra observations of three targets in Cycle-5. These observations are currently being performed. The analysis of the (limited) archival data for this sample indicated that the X-ray luminosity functions (XLF) of the discrete sources in these galaxies may not have the same shape as is widely suggested. However, any solid conclusions are hampered by the small number of detected sources. For this reason during the second year of this study, we will try to extend the sample in order to include more objects in each evolutionary stage. In addition we are completing the analysis of the Chandra monitoring observations of the Antennae galaxies. The results from this work, apart from important clues on the nature of the most luminous sources (Ultra-luminous X-ray sources; ULXs) provide evidence that source spectral and/or temporal variability does not significantly affect the shape of their X-ray luminosity functions. This is particularly important for comparisons between the XLFs of different galaxies and comparisons with predictions from theoretical models. Results from this work have been presented in several conferences. Refereed journal papers presenting these conclusions are currently in preparation. An important part of this study is the Chandra survey of the Small Magellanic Cloud, our second nearest star- forming galaxy. So far we have been awarded 5 Chandra observations of the central youngest part of the galaxy. These observations will help to study the very faint end of the young X-ray binary populations which is not possible to probe in more distant objects. Results from this study have been presented in several conferences and two papers are in preparation. In addition during year-2 we are planning of undertaking the task of identifying optical counterparts to the X-ray sources, which will help us to isolate interlopers (sources not associated with the SMC) and classify the X-ray binaries which are found to be associated with the SMC. In the theoretical front, the Star-Track X-ray binary population synthesis code which will be used for the modeling of the X-ray binary populations (led by co-I V. Kalogera and C. Belczynski), is complete. A first test using the XLF of the star-forming galaxy NGC-1569 showed remarkable agreement between the observed and the modeled XLF. These results are presented in an ApJ. Letters paper (Belczynski et al, 2004, 601, 147). During year-2 of this study we are planning of performing a parameter study in order to investigate which parameters are most important for the shape of the XLF. In addition we will perform comparisons with observations of other galaxies from our sample as they become available.
ERIC Educational Resources Information Center
Bridges, Benjamin, Jr.; Johnston, Mary P.
The impact of the tax-transfer system on the distribution of income among economic units is the subject of a number of studies by the Office of Research and Statistics of the Social Security Administration. One of the most important data sources for the work is the Census Bureau's March Current Population Survey (CPS). To conduct such studies, the…
Chronic disease surveillance systems within the US Associated Pacific Island jurisdictions.
Hosey, Gwen; Ichiho, Henry; Satterfield, Dawn; Dankwa-Mullan, Irene; Kuartei, Stevenson; Rhee, Kyu; Belyeu-Camacho, Tayna; deBrum, Ione; Demei, Yorah; Lippwe, Kipier; Luces, Patrick Solidum; Roby, Faiese
2011-07-01
In recent years, illness and death due to chronic disease in the US Associated Pacific Islands (USAPI) jurisdictions have dramatically increased. Effective chronic disease surveillance can help monitor disease trends, evaluate public policy, prioritize resource allocation, and guide program planning, evaluation, and research. Although chronic disease surveillance is being conducted in the USAPI, no recently published capacity assessments for chronic disease surveillance are available. The objective of this study was to assess the quality of existing USAPI chronic disease data sources and identify jurisdictional capacity for chronic disease surveillance. The assessment included a chronic disease data source inventory, literature review, and review of surveillance documentation available from the web or through individual jurisdictions. We used the World Health Organization's Health Metric Network Framework to assess data source quality and to identify jurisdictional capacity. Results showed that USAPI data sources are generally aligned with widely accepted chronic disease surveillance indicators and use standardized data collection methodology to measure chronic disease behavioral risks, preventive practices, illness, and death. However, all jurisdictions need to strengthen chronic disease surveillance through continued assessment and expanded support for valid and reliable data collection, analysis and reporting, dissemination, and integration among population-based and institution-based data sources. For sustained improvement, we recommend investment and technical assistance in support of a chronic disease surveillance system that integrates population-based and institution-based data sources. An integrated strategy that bridges and links USAPI data sources can support evidence-based policy and population health interventions.
Genetic and phylogenetic consequences of island biogeography.
Johnson, K P; Adler, F R; Cherry, J L
2000-04-01
Island biogeography theory predicts that the number of species on an island should increase with island size and decrease with island distance to the mainland. These predictions are generally well supported in comparative and experimental studies. These ecological, equilibrium predictions arise as a result of colonization and extinction processes. Because colonization and extinction are also important processes in evolution, we develop methods to test evolutionary predictions of island biogeography. We derive a population genetic model of island biogeography that incorporates island colonization, migration of individuals from the mainland, and extinction of island populations. The model provides a means of estimating the rates of migration and extinction from population genetic data. This model predicts that within an island population the distribution of genetic divergences with respect to the mainland source population should be bimodal, with much of the divergence dating to the colonization event. Across islands, this model predicts that populations on large islands should be on average more genetically divergent from mainland source populations than those on small islands. Likewise, populations on distant islands should be more divergent than those on close islands. Published observations of a larger proportion of endemic species on large and distant islands support these predictions.
Vandepitte, K; Gristina, A S; De Hert, K; Meekers, T; Roldán-Ruiz, I; Honnay, O
2012-09-01
Colonization is crucial to habitat restoration projects that rely on the spontaneous regeneration of the original vegetation. However, as a previously declining plant species spreads again, the likelihood of founder effects increases through recurrent population founding and associated serial bottlenecks. We related Amplified Fragment Length Polymorphism markers genetic variation and fitness to colonization history for all extant populations of the outcrossing terrestrial orchid Dactylorhiza incarnata in an isolated coastal dune complex. Around 1970, D. incarnata suffered a severe bottleneck yet ultimately persisted and gradually spread throughout the spatially segregated dune slacks, aided by the restoration of an open vegetation. Genetic assignment demonstrated dispersal to vacant sites from few nearby extant populations and very limited inflow from outside the spatially isolated reserve. Results further indicated that recurrent founding from few local sources resulted in the loss of genetic diversity and promoted genetic divergence (F(ST) = 0.35) among populations, but did not influence population fitness. The few source populations initially available and the limited inflow of genes from outside the study reserve, as a consequence of habitat degradation and spatial isolation, may have magnified the genetic effects of recurrent population founding. © 2012 Blackwell Publishing Ltd.
Kamath, Pauline L.; Sepulveda, Adam; Layhee, Megan J.
2016-01-01
Reconstructing historical colonization pathways of an invasive species is critical for uncovering factors that determine invasion success and for designing management strategies. The American bullfrog (Lithobates catesbeianus) is endemic to eastern North America, but now has a global distribution and is considered to be one of the worst invaders in the world. In Montana, several introduced populations have been reported, but little is known of their sources and vectors of introduction and secondary spread. We evaluated the genetic composition of introduced populations at local (Yellowstone River floodplain) and regional (Montana and Wyoming) scales in contrast to native range populations. Our objectives were to (1) estimate the number of introductions, (2) identify probable native sources, (3) evaluate genetic variation relative to sources, and (4) characterize properties of local- and regional-scale spread. We sequenced 937 bp of the mitochondrial cytochrome b locus in 395 tadpoles collected along 100 km of the Yellowstone River, from three additional sites in MT and a proximate site in WY. Pairwise ΦST revealed high divergence among nonnative populations, suggesting at least four independent introductions into MT from diverse sources. Three cyt b haplotypes were identical to native haplotypes distributed across the Midwest and Great Lakes regions, and AMOVA confirmed the western native region as a likely source. While haplotype (Hd = 0.69) and nucleotide diversity (π = 0.005) were low in introduced bullfrogs, the levels of diversity did not differ significantly from source populations. In the Yellowstone, two identified haplotypes implied few introduction vectors and a significant relationship between genetic and river distance was found. Evidence for multiple invasions and lack of subsequent regional spread emphasizes the importance of enforcing legislation prohibiting bullfrog importation and the need for continuing public education to prevent transport of bullfrogs in MT. More broadly, this study demonstrates how genetic approaches can reveal key properties of a biological invasion to inform management strategies.
Li, Xiaowei; Liu, Qing; Liu, Liping; Wu, Yongning
2012-05-01
To assess the distribution of dietary lead exposure in different age-gender groups of Chinese residents by using the data from China Total Diet Study, and combining the new risk assessment and the PTWI withdrawn by JECFA. Methods Combining the lead concentrations of dietary samples with the food consumption data from China Total Diet Study in 2007 to obtain the distribution of dietary intake and dietary source of lead in different age-gender population groups. Dietary lead exposure of different age-gender population groups in China was in the range of 48.7 -116.7 microg/d. The status of higher lead exposure in younger age groups was not optimistic, as the mean and median margins of exposure (MOE) have been less than 1.0 (0.1 - 0.3). The main sources of dietary lead were cereals and vegetables, which covering 57% of total lead exposure. Lowering the dietary lead exposure of Chinese residents is necessary, especially of infants and children.
Buitrago, Rosio; Bosseno, Marie-France; Depickère, Stéphanie; Waleckx, Etienne; Salas, Renata; Aliaga, Claudia; Barnabé, Christian; Brenière, Simone Frédérique
2016-04-18
Chagas disease is a major public health problem in Latin America. Its etiologic agent, Trypanosoma cruzi, is mainly transmitted through the contaminated faeces of blood-sucking insects called triatomines. Triatoma infestans is the main vector in various countries in South America and recently, several foci of wild populations of this species have been described in Bolivia and other countries. These wild populations are suspected of affecting the success of insecticide control campaigns being carried out in South America. To assess the risk that these T. infestans populations pose to human health, it is helpful to determine blood meal sources. In the present work, blood meals were identified in various Bolivian wild T. infestans populations and in three specific areas, in both wild and intra-peridomestic populations to assess the links between wild and domestic cycles of T. cruzi transmission. PCR-HDA and sequencing of Cytb gene were used to identify these blood meal sources. Fourteen vertebrate species were identified as wild blood meal sources. Of those, the most prevalent species were two Andean endemic rodents, Octodontomys gliroides (36%) and Galea musteloides (30%), while humans were the third most prevalent source (18.7%). Of 163 blood meals from peridomestic areas, more than half were chickens, and the others were generally domestic animals or humans. Interestingly, blood from wild animals was identified in triatomines captured in the peridomestic and domestic environment, and blood from domestic animals was found in triatomines captured in the wild, revealing links between wild and domestic cycles of T. cruzi transmission. The current study suggests that wild T. infestans attack humans in the wild, but is also able to bite humans in domestic settings before going back to its natural environment. These results support the risk to human health posed by wild populations of T. infestans.
A Deep NuSTAR Survey of M31: Compact object types in our Nearest Neighbor Galaxy
NASA Astrophysics Data System (ADS)
Hornschemeier, Ann E.; Wik, Daniel R.; Yukita, Mihoko; Ptak, Andrew; Venters, Tonia M.; Lehmer, Bret; Maccarone, Thomas J.; Zezas, Andreas; Harrison, Fiona; Stern, Daniel; Williams, Benjamin F.; Vulic, Neven
2017-08-01
X-ray binaries (XRBs) trace young and old stellar populations in galaxies, and thus star formation rate and star formation history/stellar mass. X-ray emission from XRBs may be responsible for significant amounts of heating of the early Intergalactic Medium at Cosmic Dawn and may also play a significant role in reionization. Until recently, the E>10 keV (hard X-ray) emission from these populations could only be studied for XRBs in our own galaxy, where it is often difficult to measure accurate distances and thus luminosities. We have observed M31 in 4 NuSTAR fields for a total exposure of 1.4 Ms, covering the young stellar population in a swath of the disk (within the footprint of the Panchromatic Hubble Andromeda Treasury (PHAT) Survey) and older populations in the bulge. We detected more than 100 sources in the 4-25 keV band, where hard band (12-25 keV) emission has allowed us to discriminate between black holes and neutron stars in different accretion states. The luminosity function of the hard band detected sources are compared to Swift/BAT and INTEGRAL-derived luminosity functions of the Milky Way population, which reveals an excess of luminous sources in M31 when correcting for star formation rate and stellar mass.
Zoonotic diseases associated with free-roaming cats.
Gerhold, R W; Jessup, D A
2013-05-01
Free-roaming cat populations have been identified as a significant public health threat and are a source for several zoonotic diseases including rabies, toxoplasmosis, cutaneous larval migrans because of various nematode parasites, plague, tularemia and murine typhus. Several of these diseases are reported to cause mortality in humans and can cause other important health issues including abortion, blindness, pruritic skin rashes and other various symptoms. A recent case of rabies in a young girl from California that likely was transmitted by a free-roaming cat underscores that free-roaming cats can be a source of zoonotic diseases. Increased attention has been placed on trap-neuter-release (TNR) programmes as a viable tool to manage cat populations. However, some studies have shown that TNR leads to increased immigration of unneutered cats into neutered populations as well as increased kitten survival in neutered groups. These compensatory mechanisms in neutered groups leading to increased kitten survival and immigration would confound rabies vaccination campaigns and produce naïve populations of cats that can serve as source of zoonotic disease agents owing to lack of immunity. This manuscript is a review of the various diseases of free-roaming cats and the public health implications associated with the cat populations. © 2012 Blackwell Verlag GmbH.
Overall mortality among patients surviving an episode of peptic ulcer bleeding
Ruigomez, A.; Rodriguez, L. A.; Hasselgren, G.; Johansson, S.; Wallander, M.
2000-01-01
STUDY OBJECTIVE—The authors investigated whether patients who have survived an acute episode of peptic ulcer bleeding (PUB) have an excess long term all cause mortality compared with the general population free of PUB. DESIGN—Follow up study of previously identified cohort of patients with a PUB episode and a general population cohort. SETTING—The source population included all people aged 30 to 89 years, registered with general practitioners in the United Kingdom. PATIENTS—All patients alive one month after the PUB episode constituted the cohort of PUB patients (n=978). A control group of 5000 people was randomly sampled from the source population. The same eligibility criteria as for patients with PUB were applied to the control series. Also, controls had to be free of PUB before start date. MAIN RESULTS—Relative risk of mortality among PUB patients was 2.1, 95%CI: 1.7, 2.6) compared with the general population. This increased mortality risk occurred mainly in the patients less than 60 years old. No difference was observed between men and women. The excess mortality was not only circumscribed to deaths attributable to recurrent gastrointestinal bleed, but also cardiovascular, cancer and other causes. CONCLUSIONS—People who have survived an acute episode of PUB have a reduced long term survival compared with the general population.This reduction was stronger among middle age patients than in the elderly. Keywords: cohort study; mortality; peptic ulcer; bleeding; population-based study PMID:10715746
Ruiz, Emma; Rodriguez, Paula; Valero, Teresa; Ávila, José M.; Aranceta-Bartrina, Javier; Gil, Ángel; González-Gross, Marcela; Ortega, Rosa M.; Serra-Majem, Lluis; Varela-Moreiras, Gregorio
2017-01-01
The consumption of total and individual sugars is controversial and little is known about consumption and dietary sources in Spain. The purpose was to examine free and intrinsic sugar intake and food and beverage sources. The ANIBES Study (Anthropometry, Intake and Energy Balance in Spain), a cross-sectional study of a representative sample of the Spanish population (9–75 years old; n = 2009) carried out in 2013, was used. Food and beverage records were obtained by a three-day dietary record by using a tablet device. The median total sugar intake was 71.5 g/day (17% Total Energy, TE), the intrinsic sugar intake was 38.3 g/day (9.6% TE), and the free sugar was 28.8 g/day (7.3% TE). Total sugar intake (free and intrinsic) was higher in men than in women for all age groups, although in terms of the contribution to total energy intake, the opposite was observed. Differences were observed for free sugar consumption dependent on age and marked differences (up to two-fold) were observed when considering the percent TE, which was much higher in children and adolescents. For the intrinsic sugar, however, a higher contribution to TE was observed in the elderly. The major sources of intrinsic sugars were fruits (31.8%), milks (19.6%), juices and nectars (11.1%), vegetables (9.89%), yogurt and fermented milk (7.18%), low-alcohol-content beverages (4,94%), bread (2.91%), and sugar soft drinks (2.24%), greater than 90% from diet contribution. As for free sugars, sources were sugar soft drinks (25.5%), sugar (17.8%), bakery and pastry items (15.2%), chocolates (11.4%), yogurt and fermented milk (6.44%), other dairy products (5.99%), jams (3.58%), juices and nectars (2.91%), and breakfast cereals and cereal bars (2.78%), summing up to 90% of the contribution. The present study demonstrates that only a moderate percentage of the Spanish population adhered to the present recommendations for total sugar intake, and urgent efforts are needed to improve diet quality in the youngest populations. PMID:28335441
Ruiz, Emma; Rodriguez, Paula; Valero, Teresa; Ávila, José M; Aranceta-Bartrina, Javier; Gil, Ángel; González-Gross, Marcela; Ortega, Rosa M; Serra-Majem, Lluis; Varela-Moreiras, Gregorio
2017-03-14
The consumption of total and individual sugars is controversial and little is known about consumption and dietary sources in Spain. The purpose was to examine free and intrinsic sugar intake and food and beverage sources. The ANIBES Study (Anthropometry, Intake and Energy Balance in Spain), a cross-sectional study of a representative sample of the Spanish population (9-75 years old; n = 2009) carried out in 2013, was used. Food and beverage records were obtained by a three-day dietary record by using a tablet device. The median total sugar intake was 71.5 g/day (17% Total Energy, TE), the intrinsic sugar intake was 38.3 g/day (9.6% TE), and the free sugar was 28.8 g/day (7.3% TE). Total sugar intake (free and intrinsic) was higher in men than in women for all age groups, although in terms of the contribution to total energy intake, the opposite was observed. Differences were observed for free sugar consumption dependent on age and marked differences (up to two-fold) were observed when considering the percent TE, which was much higher in children and adolescents. For the intrinsic sugar, however, a higher contribution to TE was observed in the elderly. The major sources of intrinsic sugars were fruits (31.8%), milks (19.6%), juices and nectars (11.1%), vegetables (9.89%), yogurt and fermented milk (7.18%), low-alcohol-content beverages (4,94%), bread (2.91%), and sugar soft drinks (2.24%), greater than 90% from diet contribution. As for free sugars, sources were sugar soft drinks (25.5%), sugar (17.8%), bakery and pastry items (15.2%), chocolates (11.4%), yogurt and fermented milk (6.44%), other dairy products (5.99%), jams (3.58%), juices and nectars (2.91%), and breakfast cereals and cereal bars (2.78%), summing up to 90% of the contribution. The present study demonstrates that only a moderate percentage of the Spanish population adhered to the present recommendations for total sugar intake, and urgent efforts are needed to improve diet quality in the youngest populations.
Managed Metapopulations: Do Salmon Hatchery ‘Sources’ Lead to In-River ‘Sinks’ in Conservation?
Johnson, Rachel C.; Weber, Peter K.; Wikert, John D.; Workman, Michelle L.; MacFarlane, R. Bruce; Grove, Marty J.; Schmitt, Axel K.
2012-01-01
Maintaining viable populations of salmon in the wild is a primary goal for many conservation and recovery programs. The frequency and extent of connectivity among natal sources defines the demographic and genetic boundaries of a population. Yet, the role that immigration of hatchery-produced adults may play in altering population dynamics and fitness of natural populations remains largely unquantified. Quantifying, whether natural populations are self-sustaining, functions as sources (population growth rate in the absence of dispersal, λ>1), or as sinks (λ<1) can be obscured by an inability to identify immigrants. In this study we use a new isotopic approach to demonstrate that a natural spawning population of Chinook salmon, (Oncorhynchus tshawytscha) considered relatively healthy, represents a sink population when the contribution of hatchery immigrants is taken into consideration. We retrieved sulfur isotopes (34S/32S, referred to as δ34S) in adult Chinook salmon otoliths (ear bones) that were deposited during their early life history as juveniles to determine whether individuals were produced in hatcheries or naturally in rivers. Our results show that only 10.3% (CI = 5.5 to 18.1%) of adults spawning in the river had otolith δ34S values less than 8.5‰, which is characteristic of naturally produced salmon. When considering the total return to the watershed (total fish in river and hatchery), we estimate that 90.7 to 99.3% (CI) of returning adults were produced in a hatchery (best estimate = 95.9%). When population growth rate of the natural population was modeled to account for the contribution of previously unidentified hatchery immigrants, we found that hatchery-produced fish caused the false appearance of positive population growth. These findings highlight the potential dangers in ignoring source-sink dynamics in recovering natural populations, and question the extent to which declines in natural salmon populations are undetected by monitoring programs. PMID:22347362
Managed Metapopulations: Do Salmon Hatchery ‘Sources’ Lead to In-River ‘Sinks’ in Conservation?
Johnson, Rachel C.; Weber, Peter K.; Wikert, John D.; ...
2012-02-08
Maintaining viable populations of salmon in the wild is a primary goal for many conservation and recovery programs. The frequency and extent of connectivity among natal sources defines the demographic and genetic boundaries of a population. Yet, the role that immigration of hatchery-produced adults may play in altering population dynamics and fitness of natural populations remains largely unquantified. Quantifying, whether natural populations are self-sustaining, functions as sources (population growth rate in the absence of dispersal, λ>1), or as sinks (λ<1) can be obscured by an inability to identify immigrants. In this study we use a new isotopic approach to demonstratemore » that a natural spawning population of Chinook salmon, (Oncorhynchus tshawytscha) considered relatively healthy, represents a sink population when the contribution of hatchery immigrants is taken into consideration. We retrieved sulfur isotopes ( 34S/ 32S, referred to as δ 34S) in adult Chinook salmon otoliths (ear bones) that were deposited during their early life history as juveniles to determine whether individuals were produced in hatcheries or naturally in rivers. Our results show that only 10.3% (CI=5.5 to 18.1%) of adults spawning in the river had otolith δ 34S values less than 8.5‰, which is characteristic of naturally produced salmon. When considering the total return to the watershed (total fish in river and hatchery), we estimate that 90.7 to 99.3% (CI) of returning adults were produced in a hatchery (best estimate=95.9%). When population growth rate of the natural population was modeled to account for the contribution of previously unidentified hatchery immigrants, we found that hatchery-produced fish caused the false appearance of positive population growth. In conclusion, these findings highlight the potential dangers in ignoring source-sink dynamics in recovering natural populations, and question the extent to which declines in natural salmon populations are undetected by monitoring programs.« less
Chakraborty, Debojyoti; Wang, Tongli; Andre, Konrad; Konnert, Monika; Lexer, Manfred J; Matulla, Christoph; Schueler, Silvio
2015-01-01
Identifying populations within tree species potentially adapted to future climatic conditions is an important requirement for reforestation and assisted migration programmes. Such populations can be identified either by empirical response functions based on correlations of quantitative traits with climate variables or by climate envelope models that compare the climate of seed sources and potential growing areas. In the present study, we analyzed the intraspecific variation in climate growth response of Douglas-fir planted within the non-analogous climate conditions of Central and continental Europe. With data from 50 common garden trials, we developed Universal Response Functions (URF) for tree height and mean basal area and compared the growth performance of the selected best performing populations with that of populations identified through a climate envelope approach. Climate variables of the trial location were found to be stronger predictors of growth performance than climate variables of the population origin. Although the precipitation regime of the population sources varied strongly none of the precipitation related climate variables of population origin was found to be significant within the models. Overall, the URFs explained more than 88% of variation in growth performance. Populations identified by the URF models originate from western Cascades and coastal areas of Washington and Oregon and show significantly higher growth performance than populations identified by the climate envelope approach under both current and climate change scenarios. The URFs predict decreasing growth performance at low and middle elevations of the case study area, but increasing growth performance on high elevation sites. Our analysis suggests that population recommendations based on empirical approaches should be preferred and population selections by climate envelope models without considering climatic constrains of growth performance should be carefully appraised before transferring populations to planting locations with novel or dissimilar climate.
Origins of extrinsic variability in eukaryotic gene expression
NASA Astrophysics Data System (ADS)
Volfson, Dmitri; Marciniak, Jennifer; Blake, William J.; Ostroff, Natalie; Tsimring, Lev S.; Hasty, Jeff
2006-02-01
Variable gene expression within a clonal population of cells has been implicated in a number of important processes including mutation and evolution, determination of cell fates and the development of genetic disease. Recent studies have demonstrated that a significant component of expression variability arises from extrinsic factors thought to influence multiple genes simultaneously, yet the biological origins of this extrinsic variability have received little attention. Here we combine computational modelling with fluorescence data generated from multiple promoter-gene inserts in Saccharomyces cerevisiae to identify two major sources of extrinsic variability. One unavoidable source arising from the coupling of gene expression with population dynamics leads to a ubiquitous lower limit for expression variability. A second source, which is modelled as originating from a common upstream transcription factor, exemplifies how regulatory networks can convert noise in upstream regulator expression into extrinsic noise at the output of a target gene. Our results highlight the importance of the interplay of gene regulatory networks with population heterogeneity for understanding the origins of cellular diversity.
Origins of extrinsic variability in eukaryotic gene expression
NASA Astrophysics Data System (ADS)
Volfson, Dmitri; Marciniak, Jennifer; Blake, William J.; Ostroff, Natalie; Tsimring, Lev S.; Hasty, Jeff
2006-03-01
Variable gene expression within a clonal population of cells has been implicated in a number of important processes including mutation and evolution, determination of cell fates and the development of genetic disease. Recent studies have demonstrated that a significant component of expression variability arises from extrinsic factors thought to influence multiple genes in concert, yet the biological origins of this extrinsic variability have received little attention. Here we combine computational modeling with fluorescence data generated from multiple promoter-gene inserts in Saccharomyces cerevisiae to identify two major sources of extrinsic variability. One unavoidable source arising from the coupling of gene expression with population dynamics leads to a ubiquitous noise floor in expression variability. A second source which is modeled as originating from a common upstream transcription factor exemplifies how regulatory networks can convert noise in upstream regulator expression into extrinsic noise at the output of a target gene. Our results highlight the importance of the interplay of gene regulatory networks with population heterogeneity for understanding the origins of cellular diversity.
Hooley-Underwood, Zachary; Mandeville, Elizabeth G.; Gerrity, Paul C.; Deromedi, J. W.; Johnson, Kevin; Walters, Annika W.
2018-01-01
Dams and water diversions fragment habitat, entrain fish, and alter fish movement. Many Burbot Lota lota populations are declining, with dams and water diversions thought to be a major threat. We used multiple methods to identify Burbot movement patterns and assess entrainment into an irrigation system in the Wind River, Wyoming. We assessed seasonal movement of Burbot with a mark–recapture (PIT tagging) study, natal origins of entrained fish with otolith microchemistry, and historic movement with genotyping by sequencing. We found limited evidence of entrainment in irrigation waters across all approaches. The mark–recapture study indicated that out‐migration from potential source populations could be influenced by flow regime but was generally low. Otolith and genomic results suggested the presence of a self‐sustaining population within the irrigation network. We conclude that emigration from natural tributary populations is not the current source of the majority of Burbot found in irrigation waters. Instead, reservoir and irrigation canal construction has created novel habitat in which Burbot have established a population. Using a multi‐scale approach increased our inferential abilities and mechanistic understanding of movement patterns between natural and managed systems.
2010-01-01
Background Feral sheep are considered to be a source of genetic variation that has been lost from their domestic counterparts through selection. Methods This study investigates variation in the genes KRTAP1-1, KRT33, ADRB3 and DQA2 in Merino-like feral sheep populations from New Zealand and its offshore islands. These genes have previously been shown to influence wool, lamb survival and animal health. Results All the genes were polymorphic, but no new allele was identified in the feral populations. In some of these populations, allele frequencies differed from those observed in commercial Merino sheep and other breeds found in New Zealand. Heterozygosity levels were comparable to those observed in other studies on feral sheep. Our results suggest that some of the feral populations may have been either inbred or outbred over the duration of their apparent isolation. Conclusion The variation described here allows us to draw some conclusions about the likely genetic origin of the populations and selective pressures that may have acted upon them, but they do not appear to be a source of new genetic material, at least for these four genes. PMID:21176141
DOE Office of Scientific and Technical Information (OSTI.GOV)
Laycock, Silas; Cappallo, Rigel; Williams, Benjamin F.
We have monitored the Cassiopeia dwarf galaxy (IC 10) in a series of 10 Chandra ACIS-S observations to capture its variable and transient X-ray source population, which is expected to be dominated by High Mass X-ray Binaries (HMXBs). We present a sample of 21 X-ray sources that are variable between observations at the 3 σ level, from a catalog of 110 unique point sources. We find four transients (flux variability ratio greater than 10) and a further eight objects with ratios >5. The observations span the years 2003–2010 and reach a limiting luminosity of >10{sup 35} erg s{sup −1}, providingmore » sensitivity to X-ray binaries in IC 10 as well as flare stars in the foreground Milky Way. The nature of the variable sources is investigated from light curves, X-ray spectra, energy quantiles, and optical counterparts. The purpose of this study is to discover the composition of the X-ray binary population in a young starburst environment. IC 10 provides a sharp contrast in stellar population age (<10 My) when compared to the Magellanic Clouds (40–200 My) where most of the known HMXBs reside. We find 10 strong HMXB candidates, 2 probable background Active Galactic Nuclei, 4 foreground flare-stars or active binaries, and 5 not yet classifiable sources. Complete classification of the sample requires optical spectroscopy for radial velocity analysis and deeper X-ray observations to obtain higher S/N spectra and search for pulsations. A catalog and supporting data set are provided.« less
Invasion pathway of the Ctenophore Mnemiopsis leidyi in the Mediterranean Sea.
Ghabooli, Sara; Shiganova, Tamara A; Briski, Elizabeta; Piraino, Stefano; Fuentes, Veronica; Thibault-Botha, Delphine; Angel, Dror L; Cristescu, Melania E; Macisaac, Hugh J
2013-01-01
Gelatinous zooplankton outbreaks have increased globally owing to a number of human-mediated factors, including food web alterations and species introductions. The invasive ctenophore Mnemiopsis leidyi entered the Black Sea in the early 1980s. The invasion was followed by the Azov, Caspian, Baltic and North Seas, and, most recently, the Mediterranean Sea. Previous studies identified two distinct invasion pathways of M. leidyi from its native range in the western Atlantic Ocean to Eurasia. However, the source of newly established populations in the Mediterranean Sea remains unclear. Here we build upon our previous study and investigate sequence variation in both mitochondrial (Cytochrome c Oxidase subunit I) and nuclear (Internal Transcribed Spacer) markers in M. leidyi, encompassing five native and 11 introduced populations, including four from the Mediterranean Sea. Extant genetic diversity in Mediterranean populations (n = 8, N a = 10) preclude the occurrence of a severe genetic bottleneck or founder effects in the initial colonizing population. Our mitochondrial and nuclear marker surveys revealed two possible pathways of introduction into Mediterranean Sea. In total, 17 haplotypes and 18 alleles were recovered from all surveyed populations. Haplotype and allelic diversity of Mediterranean populations were comparable to populations from which they were likely drawn. The distribution of genetic diversity and pattern of genetic differentiation suggest initial colonization of the Mediterranean from the Black-Azov Seas (pairwise F ST = 0.001-0.028). However, some haplotypes and alleles from the Mediterranean Sea were not detected from the well-sampled Black Sea, although they were found in Gulf of Mexico populations that were also genetically similar to those in the Mediterranean Sea (pairwise F ST = 0.010-0.032), raising the possibility of multiple invasion sources. Multiple introductions from a combination of Black Sea and native region sources could be facilitated by intense local and transcontinental shipping activity, respectively.
Invasion Pathway of the Ctenophore Mnemiopsis leidyi in the Mediterranean Sea
Ghabooli, Sara; Shiganova, Tamara A.; Briski, Elizabeta; Piraino, Stefano; Fuentes, Veronica; Thibault-Botha, Delphine; Angel, Dror L.; Cristescu, Melania E.; MacIsaac, Hugh J.
2013-01-01
Gelatinous zooplankton outbreaks have increased globally owing to a number of human-mediated factors, including food web alterations and species introductions. The invasive ctenophore Mnemiopsis leidyi entered the Black Sea in the early 1980s. The invasion was followed by the Azov, Caspian, Baltic and North Seas, and, most recently, the Mediterranean Sea. Previous studies identified two distinct invasion pathways of M. leidyi from its native range in the western Atlantic Ocean to Eurasia. However, the source of newly established populations in the Mediterranean Sea remains unclear. Here we build upon our previous study and investigate sequence variation in both mitochondrial (Cytochrome c Oxidase subunit I) and nuclear (Internal Transcribed Spacer) markers in M. leidyi, encompassing five native and 11 introduced populations, including four from the Mediterranean Sea. Extant genetic diversity in Mediterranean populations (n = 8, N a = 10) preclude the occurrence of a severe genetic bottleneck or founder effects in the initial colonizing population. Our mitochondrial and nuclear marker surveys revealed two possible pathways of introduction into Mediterranean Sea. In total, 17 haplotypes and 18 alleles were recovered from all surveyed populations. Haplotype and allelic diversity of Mediterranean populations were comparable to populations from which they were likely drawn. The distribution of genetic diversity and pattern of genetic differentiation suggest initial colonization of the Mediterranean from the Black-Azov Seas (pairwise F ST = 0.001–0.028). However, some haplotypes and alleles from the Mediterranean Sea were not detected from the well-sampled Black Sea, although they were found in Gulf of Mexico populations that were also genetically similar to those in the Mediterranean Sea (pairwise F ST = 0.010–0.032), raising the possibility of multiple invasion sources. Multiple introductions from a combination of Black Sea and native region sources could be facilitated by intense local and transcontinental shipping activity, respectively. PMID:24303030
Monitoring trends in bird populations: addressing background levels of annual variability in counts
Jared Verner; Kathryn L. Purcell; Jennifer G. Turner
1996-01-01
Point counting has been widely accepted as a method for monitoring trends in bird populations. Using a rigorously standardized protocol at 210 counting stations at the San Joaquin Experimental Range, Madera Co., California, we have been studying sources of variability in point counts of birds. Vegetation types in the study area have not changed during the 11 years of...
Ort, Brian S; Cohen, C Sarah; Boyer, Katharyn E; Reynolds, Laura K; Tam, Sheh May; Wyllie-Echeverria, Sandy
2014-01-01
Eelgrass (Zostera marina) forms the foundation of an important shallow coastal community in protected estuaries and bays. Widespread population declines have stimulated restoration efforts, but these have often overlooked the importance of maintaining the evolutionary potential of restored populations by minimizing the reduction in genetic diversity that typically accompanies restoration. In an experiment simulating a small-scale restoration, we tested the effectiveness of a buoy-deployed seeding technique to maintain genetic diversity comparable to the seed source populations. Seeds from three extant source populations in San Francisco Bay were introduced into eighteen flow-through baywater mesocosms. Following seedling establishment, we used seven polymorphic microsatellite loci to compare genetic diversity indices from 128 shoots to those found in the source populations. Importantly, allelic richness and expected heterozygosity were not significantly reduced in the mesocosms, which also preserved the strong population differentiation present among source populations. However, the inbreeding coefficient F IS was elevated in two of the three sets of mesocosms when they were grouped according to their source population. This is probably a Wahlund effect from confining all half-siblings within each spathe to a single mesocosm, elevating F IS when the mesocosms were considered together. The conservation of most alleles and preservation of expected heterozygosity suggests that this seeding technique is an improvement over whole-shoot transplantation in the conservation of genetic diversity in eelgrass restoration efforts.
Ort, Brian S.; Cohen, C. Sarah; Boyer, Katharyn E.; Reynolds, Laura K.; Tam, Sheh May; Wyllie-Echeverria, Sandy
2014-01-01
Eelgrass (Zostera marina) forms the foundation of an important shallow coastal community in protected estuaries and bays. Widespread population declines have stimulated restoration efforts, but these have often overlooked the importance of maintaining the evolutionary potential of restored populations by minimizing the reduction in genetic diversity that typically accompanies restoration. In an experiment simulating a small-scale restoration, we tested the effectiveness of a buoy-deployed seeding technique to maintain genetic diversity comparable to the seed source populations. Seeds from three extant source populations in San Francisco Bay were introduced into eighteen flow-through baywater mesocosms. Following seedling establishment, we used seven polymorphic microsatellite loci to compare genetic diversity indices from 128 shoots to those found in the source populations. Importantly, allelic richness and expected heterozygosity were not significantly reduced in the mesocosms, which also preserved the strong population differentiation present among source populations. However, the inbreeding coefficient F IS was elevated in two of the three sets of mesocosms when they were grouped according to their source population. This is probably a Wahlund effect from confining all half-siblings within each spathe to a single mesocosm, elevating F IS when the mesocosms were considered together. The conservation of most alleles and preservation of expected heterozygosity suggests that this seeding technique is an improvement over whole-shoot transplantation in the conservation of genetic diversity in eelgrass restoration efforts. PMID:24586683
The modifying effect of the building envelope on population exposure to PM2.5 from outdoor sources
Taylor, J; Shrubsole, C; Davies, M; Biddulph, P; Das, P; Hamilton, I; Vardoulakis, S; Mavrogianni, A; Jones, B; Oikonomou, E
2014-01-01
A number of studies have estimated population exposure to PM2.5 by examining modeled or measured outdoor PM2.5 levels. However, few have taken into account the mediating effects of building characteristics on the ingress of PM2.5 from outdoor sources and its impact on population exposure in the indoor domestic environment. This study describes how building simulation can be used to determine the indoor concentration of outdoor-sourced pollution for different housing typologies and how the results can be mapped using building stock models and Geographical Information Systems software to demonstrate the modifying effect of dwellings on occupant exposure to PM2.5 across London. Building archetypes broadly representative of those in the Greater London Authority were simulated for pollution infiltration using EnergyPlus. In addition, the influence of occupant behavior on indoor levels of PM2.5 from outdoor sources was examined using a temperature-dependent window-opening scenario. Results demonstrate a range of I/O ratios of PM2.5, with detached and semi-detached dwellings most vulnerable to high levels of infiltration. When the results are mapped, central London shows lower I/O ratios of PM2.5 compared with outer London, an apparent inversion of exposure most likely caused by the prevalence of flats rather than detached or semi-detached properties. PMID:24713025
NASA Astrophysics Data System (ADS)
Frissell, N. A.; Baker, J. B. H.; Ruohoniemi, J. M.; Gerrard, A. J.; Miller, E. S.; West, M. L.; Bristow, W.
2014-12-01
Medium Scale Traveling Ionospheric Disturbances (MSTIDs) are wave-like perturbations of the F-region ionosphere with horizontal wavelengths on the order of 100-250 km and periods between ~15 - 60 min. In SuperDARN data, MSTID signatures are manifested as quasi-periodic enhancements of ground scatter power moving through the radar FOV. High latitude SuperDARN MSTIDs have been studied for many years and are generally attributed to atmospheric gravity waves (AGWs) launched by auroral sources. Recent extension of the SuperDARN network to midlatitudes has revealed that MSTIDs are routinely observed at midlatitudes as well. Our previous research using the single radar in Blackstone, Virginia found a primary MSTID propagation direction which suggests that high latitude activity is also the primary source of midlatitude MSTIDs. However, there is also a population of MSTIDs that could be generated by tropospheric sources. This study extends this research by surveying multiple midlatitude radars in Oregon (CVW and CVE), Kansas (FHW and FHW) and Virginia (BKS and WAL) from 1 November 2012 through 1 January 2013 for MSTID signatures in order understand the longitudinal distribution of midlatitude MSTID characteristics and understand possible influences of varied terrain on MSTID observations. MSTIDs observed by all radars had typical wavelengths between 250 to 500 km and horizontal velocities between 100 and 250 m/s. In all radars, the dominant population of MSTIDs propagated in a southward direction, ranging from 135˚ to 250˚ geographic azimuth. The dominant southward propagation direction suggests auroral sources are the dominant source of MSTIDs observed by SuperDARN radars at midlatitudes, which reinforces findings regarding the primary population in previous work.
Open source electronic health records and chronic disease management.
Goldwater, Jason C; Kwon, Nancy J; Nathanson, Ashley; Muckle, Alison E; Brown, Alexa; Cornejo, Kerri
2014-02-01
To study and report on the use of open source electronic health records (EHR) to assist with chronic care management within safety net medical settings, such as community health centers (CHC). The study was conducted by NORC at the University of Chicago from April to September 2010. The NORC team undertook a comprehensive environmental scan, including a literature review, a dozen key informant interviews using a semistructured protocol, and a series of site visits to CHC that currently use an open source EHR. Two of the sites chosen by NORC were actively using an open source EHR to assist in the redesign of their care delivery system to support more effective chronic disease management. This included incorporating the chronic care model into an CHC and using the EHR to help facilitate its elements, such as care teams for patients, in addition to maintaining health records on indigent populations, such as tuberculosis status on homeless patients. The ability to modify the open-source EHR to adapt to the CHC environment and leverage the ecosystem of providers and users to assist in this process provided significant advantages in chronic care management. Improvements in diabetes management, controlled hypertension and increases in tuberculosis vaccinations were assisted through the use of these open source systems. The flexibility and adaptability of open source EHR demonstrated its utility and viability in the provision of necessary and needed chronic disease care among populations served by CHC.
Carlson, Jane E; Adams, Christopher A; Holsinger, Kent E
2016-01-01
Trait-environment relationships are commonly interpreted as evidence for local adaptation in plants. However, even when selection analyses support this interpretation, the mechanisms underlying differential benefits are often unknown. This study addresses this gap in knowledge using the broadly distributed South African shrub Protea repens. Specifically, the study examines whether broad-scale patterns of trait variation are consistent with spatial differences in selection and ecophysiology in the wild. In a common garden study of plants sourced from 19 populations, associations were measured between five morphological traits and three axes describing source climates. Trait-trait and trait-environment associations were analysed in a multi-response model. Within two focal populations in the wild, selection and path analyses were used to test associations between traits, fecundity and physiological performance. Across 19 populations in a common garden, stomatal density increased with the source population's mean annual temperature and decreased with its average amount of rainfall in midsummer. Concordantly, selection analysis in two natural populations revealed positive selection on stomatal density at the hotter, drier site, while failing to detect selection at the cooler, moister site. Dry-site plants with high stomatal density also had higher stomatal conductances, cooler leaf temperatures and higher light-saturated photosynthetic rates than those with low stomatal density, but no such relationships were present among wet-site plants. Leaf area, stomatal pore index and specific leaf area in the garden also co-varied with climate, but within-population differences were not associated with fitness in either wild population. The parallel patterns of broad-scale variation, differences in selection and differences in trait-ecophysiology relationships suggest a mechanism for adaptive differentiation in stomatal density. Densely packed stomata may improve performance by increasing transpiration and cooling, but predominately in drier, hotter climates. This study uniquely shows context-dependent benefits of stomatal density--a trait rarely linked to local adaptation in plants. © The Author 2015. Published by Oxford University Press on behalf of the Annals of Botany Company. All rights reserved. For Permissions, please email: journals.permissions@oup.com.
Two Populations of SiO Masers in the Galactic Bulge
NASA Astrophysics Data System (ADS)
Trapp, Adam; Rich, Robert Michael; Morris, Mark; Pihlstrom, Ylva; Sjouwerman, Lorant; Claussen, Mark J.; Stroh, Michael
2017-01-01
We present a summary of the kinematics of stellar SiO masers observed in the direction of the galactic bulge with ALMA (885 sources), and the JVLA (2,479 sources). These objects are selected by color from the MSX point source catalog, which has given an SiO detection rate of ~70%. The presented sample, along with the ~24,000 sources still being observed and reduced, enable radial velocity measurements even in regions with extreme optical extinction. These maser stars are compared to the known bulge surveys: APOGEE (~25,000 sources), BRAVA (~8000 sources), and GIBS (~6,400 sources). We have found that BAaDE stars in the direction of the bulge exist in two subpopulations: (1) A kinematically hot population exhibiting cylindrical rotation consistent with the other bulge surveys, and (2) a kinematically cold population more consistent with a disk population. In the ALMA data, we find evidence for a -200 km/s feature at (l,b) = (-9,0), possibly the symmetric complement to a previously proposed +200 km/s feature (Nidever 2012), that we do not confirm with our data.
Grefenstette, John J; Brown, Shawn T; Rosenfeld, Roni; DePasse, Jay; Stone, Nathan T B; Cooley, Phillip C; Wheaton, William D; Fyshe, Alona; Galloway, David D; Sriram, Anuroop; Guclu, Hasan; Abraham, Thomas; Burke, Donald S
2013-10-08
Mathematical and computational models provide valuable tools that help public health planners to evaluate competing health interventions, especially for novel circumstances that cannot be examined through observational or controlled studies, such as pandemic influenza. The spread of diseases like influenza depends on the mixing patterns within the population, and these mixing patterns depend in part on local factors including the spatial distribution and age structure of the population, the distribution of size and composition of households, employment status and commuting patterns of adults, and the size and age structure of schools. Finally, public health planners must take into account the health behavior patterns of the population, patterns that often vary according to socioeconomic factors such as race, household income, and education levels. FRED (a Framework for Reconstructing Epidemic Dynamics) is a freely available open-source agent-based modeling system based closely on models used in previously published studies of pandemic influenza. This version of FRED uses open-access census-based synthetic populations that capture the demographic and geographic heterogeneities of the population, including realistic household, school, and workplace social networks. FRED epidemic models are currently available for every state and county in the United States, and for selected international locations. State and county public health planners can use FRED to explore the effects of possible influenza epidemics in specific geographic regions of interest and to help evaluate the effect of interventions such as vaccination programs and school closure policies. FRED is available under a free open source license in order to contribute to the development of better modeling tools and to encourage open discussion of modeling tools being used to evaluate public health policies. We also welcome participation by other researchers in the further development of FRED.
Novy, Ari; Jones, Kenneth C
2011-10-01
Microsatellite markers were developed for the medicinal plant Tripterygium (Celastraceae) to assess its population structure and to facilitate source tracking of plant materials used for medicinal extracts. Ten microsatellite markers were isolated and characterized in T. wilfordii using an enriched genomic library. The number of alleles per locus ranged from five to 12. Observed and expected heterozygosity ranged from 0.166 to 0.630 and 0.392 to 0.562, respectively. These markers will be useful for a variety of applications including source tracking of plant materials, resolution of taxonomic issues, and population genetics studies.
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.
Recruiting Vulnerable Populations into Research: A Systematic Review of Recruitment Interventions
UyBico, Stacy J.; Pavel, Shani
2007-01-01
Background Members of vulnerable populations are underrepresented in research studies. Objective To evaluate and synthesize the evidence regarding interventions to enhance enrollment of vulnerable populations into health research studies. Data sources Studies were identified by searching MEDLINE, the Web of Science database, personal sources, hand searching of related journals, and article references. Studies that contained data on recruitment interventions for vulnerable populations (minority, underserved, poor, rural, urban, or inner city) and for which the parent study (study for which recruitment was taking place) was an intervention study were included. A total of 2,648 study titles were screened and 48 articles met inclusion criteria, representing 56 parent studies. Two investigators extracted data from each study. Results African Americans were the most frequently targeted population (82% of the studies), while 46% targeted Hispanics/Latinos. Many studies assessed 2 or more interventions, including social marketing (82% of studies), community outreach (80%), health system recruitment (52%), and referrals (28%). The methodologic rigor varied substantially. Only 40 studies (71%) incorporated a control group and 21% used statistical analysis to compare interventions. Social marketing, health system, and referral recruitment were each found to be the most successful intervention about 35–45% of the studies in which they were attempted, while community outreach was the most successful intervention in only 2 of 16 studies (13%) in which it was employed. People contacted as a result of social marketing were no less likely to enroll than people contacted through other mechanisms. Conclusions Further work with greater methodologic rigor is needed to identify evidence-based strategies for increasing minority enrollment in research studies; community outreach, as an isolated strategy, may be less successful than other strategies. PMID:17375358
Galactic gamma-ray sources, SNOBs, and giant H2 regions
NASA Technical Reports Server (NTRS)
Montmerle, T.
1985-01-01
Progress towards understanding the nature of the COS-B galactic gamma-ray sources was made by two recent developments. The developments are: (1) the existence of extensive wide-latitude CO surveys, from the Northern Hemisphere, and from the Southern Hemisphere which give more precise information on molecular cloud population of the Perseus, Sagittarius, and Carina spiral arms; (2) the study of the time variability of gamma-ray sources in gamma-rays but also at other wavelengths, leading to the discovery of four new variable sources in addition to the already known Crab and Vela pulsars. Three classes of gamma-ray sources are found; invariable sources, active sources, and passive sources.
Love, Heather M.; Maggs, Christine A.; Murray, Tomás E.; Provan, Jim
2013-01-01
Background and Aims Riparian systems are prone to invasion by alien plant species. The spread of invasive riparian plants may be facilitated by hydrochory, the transport of seeds by water, but while ecological studies have highlighted the possible role of upstream source populations in the establishment and persistence of stands of invasive riparian plant species, population genetic studies have as yet not fully addressed the potential role of hydrochoric dispersal in such systems. Methods A population genetics approach based on a replicated bifurcate sampling design is used to test hypotheses consistent with patterns of unidirectional, linear gene flow expected under hydrochoric dispersal of the invasive riparian plant Impatiens glandulifera in two contrasting river systems. Key results A significant increase in levels of genetic diversity downstream was observed, consistent with the accumulation of propagules from upstream source populations, and strong evidence was found for organization of this diversity between different tributaries, reflecting the dendritic organization of the river systems studied. Conclusions These findings indicate that hydrochory, rather than anthropogenic dispersal, is primarily responsible for the spread of I. glandulifera in these river systems, and this is relevant to potential approaches to the control of invasive riparian plant species. PMID:24169594
NASA Astrophysics Data System (ADS)
Bespalov, Yurii G.; Nosov, Konstantin V.; Vysotska, Olena V.; Porvan, Andrii P.; Omiotek, Zbigniew; Burlibay, Aron; Assembay, Azat; Szatkowska, Małgorzata
2017-08-01
This study aims at mathematical modeling of systemic factors threatening the sanitary and hygienic state of sources of water supply. It is well-known, that this state affects health of population consuming water from different water sources (lakes, reservoirs, rivers). In particular, water quality problem may cause allergic reactions that are the important problem of health care. In the paper, the authors present the mathematical model, that enables on the basis of observations of a natural system to predict the system's behavior and determine the risks related to deterioration of drinking water resources. As a case study, we uses supply of drinking water from Lake Sevan, but the approach developed in the study can be applied to wide area of adjacent problems.
USDA-ARS?s Scientific Manuscript database
Increasing food production is essential to meet the demands of a growing human population, with its rising income levels and nutritional expectations. New sources of genetic variation are key to enhancing the productivity, sustainability and resilience of crop varieties and agricultural systems that...
Monitoring bird populations: the role of bird observatories and nongovernmental organizations
Geoffrey R. Geupel; Nadav Nur
1993-01-01
Nongovernmental organizations (NGOs) currently participating in Partners in Flight have been monitoring bird populations in North America for decades. These regional organization have strong grass roots and private sector support and are able to conduct truly long term studies by using nontraditional funding sources and staffing with dedicated volunteers and personnel...
ERIC Educational Resources Information Center
Fitzpatrick, Kate R.; Henninger, Jacqueline C.; Taylor, Don M.
2014-01-01
The purpose of this collective instrumental case study was to examine the experiences of six undergraduate students from traditionally marginalized populations with regard to their preparation for, admission to, and retention within a music education degree program. Analyzed and reported through the lens of critical theory, data sources included…
The ultimate goal of risk assessment is to estimate the adverse effects of exposures to environmental contaminants in the population. However, populations of humans and other species vary widely in many key factors such as age, genetic makeup, gender, and health status. Any or a...
Eric R. Waits; Mark J. Bagley; Michael J. Blum; Frank H. McCormick; James M. Lazorchak
2008-01-01
Relating local demographic processes to spatial structure (e.g. habitat heterogeneity) is essential for understanding population and species persistence (Hanski & Gilpin, 1997; Fagan, 2002). Yet few studies have tested general hypotheses about the importance of spatial patterns in determining population dynamics within riverÂstream networks (Lowe, Likens &...
NASA Astrophysics Data System (ADS)
Tu, W.; Cunningham, G.; Reeves, G. D.; Chen, Y.; Henderson, M. G.; Blake, J. B.; Baker, D. N.; Spence, H.
2013-12-01
During the October 8-9 2012 storm, the MeV electron fluxes in the heart of the outer radiation belt are first wiped out then exhibit a three-orders-of-magnitude increase on the timescale of hours, as observed by the MagEIS and REPT instruments aboard the Van Allen Probes. There is strong observational evidence that the remarkable enhancement is due to local acceleration by chorus waves, as shown in the recent Science paper by Reeves et al.1. However, the importance of the dynamic electron source population transported in from the plasma sheet, to the observed remarkable enhancement, has not been studied. We illustrate the importance of the source population with our simulation of the event using the DREAM 3D diffusion model. Three new modifications have been implemented in the model: 1) incorporating a realistic and time-dependent low-energy boundary condition at 100 keV obtained from the MagEIS data; 2) utilizing event-specific chorus wave distributions derived from the low-energy electron precipitation observed by POES and validated against the in situ wave data from EMFISIS; 3) using an ';open' boundary condition at L*=11 and implementing electron lifetimes on the order of the drift period outside the solar-wind driven last closed drift shell. The model quantitatively reproduces the MeV electron dynamics during this event, including the fast dropout at the start of Oct. 8th, low electron flux during the first Dst dip, and the remarkable enhancement peaked at L*=4.2 during the second Dst dip. By comparing the model results with realistic source population against those with constant low-energy boundary (see figure), we find that the realistic electron source population is critical to reproduce the observed fast and significant increase of MeV electrons. 1Reeves, G. D., et al. (2013), Electron Acceleration in the Heart of the Van Allen Radiation Belts, Science, DOI:10.1126/science.1237743. Comparison between data and model results during the October 2012 storm for electrons at μ=3168 MeV/G and K=0.1 G1/2Re. Top plot is the electron phase space density data measured by the two Van Allen Probes; middle plot shows the results from the DREAM 3D diffusion model with a realistic electron source population derived from MagEIS data; and the bottom plot is the model results with a constant source population.
Exploring abortion attitudes of US adolescents and young adults using social media.
Altshuler, Anna L; Gerns Storey, Helen L; Prager, Sarah W
2015-03-01
To explore the use of social media for recruitment of adolescents and young adults in the United States and to describe how they learn and feel about abortion. Americans 13-29years of age were recruited through web-based social media to complete an online survey about sex and pregnancy-related decision making, including abortion. Descriptive statistics were used to compare the study population's demographics and prevalence of sexual experience to national databases [US Census and National Survey of Family Growth (NSFG)] and to describe abortion attitudes and related topics. Survey completion rate was 78% and 996 participants' responses were analyzed. The study population appeared diverse with respect to gender, ethnicity, race and geographic distribution with some similarities to the US Census and was sexually active at an earlier age compared to the NSFG. While the majority of participants supported abortion (74%), acceptance of abortion for themselves or their partners varied based on circumstances. The media were the most popular sources of information for learning about sex and abortion (73% and 68%, respectively). Parents had the most influence on individuals' abortion stances compared to other sources. Social media recruitment, compared to traditional methods, has the potential to reach a geographically, ethnically and racially diverse group of young people to study sensitive topics in an economical and expedient fashion. Similar to the general population, the study population's abortion views fell on a spectrum with overall supportive attitudes toward abortion. The media served as common sources of information for learning about both sex and abortion. Web-based social media offer a novel recruiting strategy to study sensitive topics such as abortion attitudes among difficult-to-reach populations such as adolescents and young adults. The presented findings begin characterizing young people's abortion attitudes, offering a foundation for more in-depth research. Copyright © 2015 Elsevier Inc. All rights reserved.
NASA Astrophysics Data System (ADS)
Duncan, Kenneth J.; Jarvis, Matt J.; Brown, Michael J. I.; Röttgering, Huub J. A.
2018-07-01
Building on the first paper in this series (Duncan et al. 2018), we present a study investigating the performance of Gaussian process photometric redshift (photo-z) estimates for galaxies and active galactic nuclei (AGNs) detected in deep radio continuum surveys. A Gaussian process redshift code is used to produce photo-z estimates targeting specific subsets of both the AGN population - infrared (IR), X-ray, and optically selected AGNs - and the general galaxy population. The new estimates for the AGN population are found to perform significantly better at z > 1 than the template-based photo-z estimates presented in our previous study. Our new photo-z estimates are then combined with template estimates through hierarchical Bayesian combination to produce a hybrid consensus estimate that outperforms both of the individual methods across all source types. Photo-z estimates for radio sources that are X-ray sources or optical/IR AGNs are significantly improved in comparison to previous template-only estimates - with outlier fractions and robust scatter reduced by up to a factor of ˜4. The ability of our method to combine the strengths of the two input photo-z techniques and the large improvements we observe illustrate its potential for enabling future exploitation of deep radio continuum surveys for both the study of galaxy and black hole coevolution and for cosmological studies.
Senn, Helen; Ogden, Rob; Frosch, Christiane; Syrůčková, Alena; Campbell-Palmer, Roisin; Munclinger, Pavel; Durka, Walter; Kraus, Robert H S; Saveljev, Alexander P; Nowak, Carsten; Stubbe, Annegret; Stubbe, Michael; Michaux, Johan; Lavrov, Vladimir; Samiya, Ravchig; Ulevicius, Alius; Rosell, Frank
2014-01-01
Many reintroduction projects for conservation fail, and there are a large number of factors that may contribute to failure. Genetic analysis can be used to help stack the odds of a reintroduction in favour of success, by conducting assessment of source populations to evaluate the possibility of inbreeding and outbreeding depression and by conducting postrelease monitoring. In this study, we use a panel of 306 SNP (single nucleotide polymorphism) markers and 487–489 base pairs of mitochondrial DNA control region sequence data to examine 321 individuals from possible source populations of the Eurasian beaver for a reintroduction to Scotland. We use this information to reassess the phylogenetic history of the Eurasian beavers, to examine the genetic legacy of past reintroductions on the Eurasian landmass and to assess the future power of the genetic markers to conduct ongoing monitoring via parentage analysis and individual identification. We demonstrate the capacity of medium density genetic data (hundreds of SNPs) to provide information suitable for applied conservation and discuss the difficulty of balancing the need for high genetic diversity against phylogenetic best fit when choosing source population(s) for reintroduction. PMID:25067948
Budy, Phaedra; Bowerman, Tracy; Al-Chokhachy, Robert K.; Conner, Mary; Schaller, Howard
2017-01-01
Temporal symmetry models (TSM) represent advances in the analytical application of mark–recapture data to population status assessments. For a population of char, we employed 10 years of active and passive mark–recapture data to quantify population growth rates using different data sources and analytical approaches. Estimates of adult population growth rate were 1.01 (95% confidence interval = 0.84–1.20) using a temporal symmetry model (λTSM), 0.96 (0.68–1.34) based on logistic regressions of annual snorkel data (λA), and 0.92 (0.77–1.11) from redd counts (λR). Top-performing TSMs included an increasing time trend in recruitment (f) and changes in capture probability (p). There was only a 1% chance the population decreased ≥50%, and a 10% chance it decreased ≥30% (λMCMC; based on Bayesian Markov chain Monte Carlo procedure). Size structure was stable; however, the adult population was dominated by small adults, and over the study period there was a decline in the contribution of large adults to total biomass. Juvenile condition decreased with increasing adult densities. Utilization of these different information sources provided a robust weight-of-evidence approach to identifying population status and potential mechanisms driving changes in population growth rates.
Observations of galactic X-ray sources by OSO-7
NASA Technical Reports Server (NTRS)
Markert, T. H.; Canizares, C. R.; Clark, G. W.; Hearn, D. R.; Li, F. K.; Sprott, G. F.; Winkler, P. F.
1977-01-01
We present the MIT data from the OSO-7 satellite for observations of the galactic plane between 1971 and 1974. A number of sources discovered in the MIT all-sky survey are described in detail: MX 0049 + 59, MX 0836 - 42, MX 1353 - 64, MX 1406 - 61, MX 1418 - 61, MX 1709 - 40, and MX 1608 - 52 (the persistent source suggested to be associated with the X-ray burst source XB 1608 - 52). Upper limits to the X-ray emission from a number of interesting objects are also derived. General results describing all of our observations of galactic sources are presented. Specifically, we display the number-intensity diagrams, luminosity functions, and color-color diagrams for all of the sources we detected. The data are divided between disk and bulge populations, and the characteristics of the two groups are contrasted. Finally, the concept of X-ray source populations and the relationship of globular cluster sources and burst sources to the disk and bulge populations are discussed.
NASA Astrophysics Data System (ADS)
Chhetri, R.; Ekers, R. D.; Morgan, J.; Macquart, J.-P.; Franzen, T. M. O.
2018-06-01
We use Murchison Widefield Array observations of interplanetary scintillation (IPS) to determine the source counts of point (<0.3 arcsecond extent) sources and of all sources with some subarcsecond structure, at 162 MHz. We have developed the methodology to derive these counts directly from the IPS observables, while taking into account changes in sensitivity across the survey area. The counts of sources with compact structure follow the behaviour of the dominant source population above ˜3 Jy but below this they show Euclidean behaviour. We compare our counts to those predicted by simulations and find a good agreement for our counts of sources with compact structure, but significant disagreement for point source counts. Using low radio frequency SEDs from the GLEAM survey, we classify point sources as Compact Steep-Spectrum (CSS), flat spectrum, or peaked. If we consider the CSS sources to be the more evolved counterparts of the peaked sources, the two categories combined comprise approximately 80% of the point source population. We calculate densities of potential calibrators brighter than 0.4 Jy at low frequencies and find 0.2 sources per square degrees for point sources, rising to 0.7 sources per square degree if sources with more complex arcsecond structure are included. We extrapolate to estimate 4.6 sources per square degrees at 0.04 Jy. We find that a peaked spectrum is an excellent predictor for compactness at low frequencies, increasing the number of good calibrators by a factor of three compared to the usual flat spectrum criterion.
sourceR: Classification and source attribution of infectious agents among heterogeneous populations
French, Nigel
2017-01-01
Zoonotic diseases are a major cause of morbidity, and productivity losses in both human and animal populations. Identifying the source of food-borne zoonoses (e.g. an animal reservoir or food product) is crucial for the identification and prioritisation of food safety interventions. For many zoonotic diseases it is difficult to attribute human cases to sources of infection because there is little epidemiological information on the cases. However, microbial strain typing allows zoonotic pathogens to be categorised, and the relative frequencies of the strain types among the sources and in human cases allows inference on the likely source of each infection. We introduce sourceR, an R package for quantitative source attribution, aimed at food-borne diseases. It implements a Bayesian model using strain-typed surveillance data from both human cases and source samples, capable of identifying important sources of infection. The model measures the force of infection from each source, allowing for varying survivability, pathogenicity and virulence of pathogen strains, and varying abilities of the sources to act as vehicles of infection. A Bayesian non-parametric (Dirichlet process) approach is used to cluster pathogen strain types by epidemiological behaviour, avoiding model overfitting and allowing detection of strain types associated with potentially high “virulence”. sourceR is demonstrated using Campylobacter jejuni isolate data collected in New Zealand between 2005 and 2008. Chicken from a particular poultry supplier was identified as the major source of campylobacteriosis, which is qualitatively similar to results of previous studies using the same dataset. Additionally, the software identifies a cluster of 9 multilocus sequence types with abnormally high ‘virulence’ in humans. sourceR enables straightforward attribution of cases of zoonotic infection to putative sources of infection. As sourceR develops, we intend it to become an important and flexible resource for food-borne disease attribution studies. PMID:28558033
Morphology and distribution of seamounts surrounding Easter Island
Rappaport, Y.; Naar, D.F.; Barton, C.C.; Liu, Z.-J.; Hey, R.N.
1997-01-01
We investigate the morphology and distribution of a seamount population on a section of seafloor influenced by both superfast seafloor spreading and hotspot volcanism. The population under investigation is part of a broad chain of seamounts extending eastward from the East Pacific Rise, near Easter Island. In order to define the morphological variability of the seamounts, basal shape, cross-sectional area, volume, flatness, and flank slope are plotted against height for 383 seamounts with heights greater than 200 m, based on bathymetry data collected by GLORI-B and SeaBeam 2000, during three cruises onboard the R/V Melville in the spring of 1993. Nearly complete swath mapping coverage of the seamounts is available for the analysis of size and shape distribution. We quantitatively describe the seamount population of this active region, in which seamounts cover ???27% of the seafloor, and account for ???4.2% of the total crustal volume. Over 50% of the total volume (61,000 km3) of seamounts used in this study is made up by the 14 largest seamounts, and the remaining volume is made up by the 369 smaller seamounts (>200 m in height). Our analysis indicates there are at least two seamount populations in the Easter Island-Salas y Gomez Island (25??-29??S, 113??-104??W) study area. One population of seamounts is composed of short seamounts (1200 m), shield-like, pointy cones (flatness ???1200 m) originate exclusively from a hotspot source, but only a portion of the smaller volcanoes (??1200 m) are formed from a hotspot source. The remainder would be presumably formed by a normal mantle or mixed source.
Self-perception of the antecedents of loneliness among new mothers and pregnant women.
Rokach, Ami
2007-02-01
This study examined the perceived causes of loneliness of pregnant women and mothers during the first year after childbirth experience. These were compared with the causes of loneliness of women in the general population. 91 pregnant women, 97 women during the first year following childbirth, and 208 women from the general population (M age = 30.4, SD = 10.4) answered a 29-item Loneliness Antecedents Questionnaire. In the questionnaire were 5 dimensions of sources of loneliness, namely, Personal Inadequacies, Developmental Deficits, Unfulfilling Intimate Relationships, Relocation/Significant Separation, and Social Marginality. Sources of loneliness were significantly different amongst the three groups. The differences were confined to the Personal Inadequacies, and the Relocation/Significant Separation subscales. In both, women from the general population had the highest mean subscale scores.
Remotely measuring populations during a crisis by overlaying two data sources
Bharti, Nita; Lu, Xin; Bengtsson, Linus; Wetter, Erik; Tatem, Andrew J.
2015-01-01
Background Societal instability and crises can cause rapid, large-scale movements. These movements are poorly understood and difficult to measure but strongly impact health. Data on these movements are important for planning response efforts. We retrospectively analyzed movement patterns surrounding a 2010 humanitarian crisis caused by internal political conflict in Côte d'Ivoire using two different methods. Methods We used two remote measures, nighttime lights satellite imagery and anonymized mobile phone call detail records, to assess average population sizes as well as dynamic population changes. These data sources detect movements across different spatial and temporal scales. Results The two data sources showed strong agreement in average measures of population sizes. Because the spatiotemporal resolution of the data sources differed, we were able to obtain measurements on long- and short-term dynamic elements of populations at different points throughout the crisis. Conclusions Using complementary, remote data sources to measure movement shows promise for future use in humanitarian crises. We conclude with challenges of remotely measuring movement and provide suggestions for future research and methodological developments. PMID:25733558
Hutchinson, Rebecca Newlin; Shin, Sonya
2014-01-01
Background American Indians and Alaska Native (AI/AN) populations experience significant health disparities compared to non-Hispanic white populations. Cardiovascular disease and related risk factors are increasingly recognized as growing indicators of global health disparities. However, comparative reports on disparities among this constellation of diseases for AI/AN populations have not been systematically reviewed. Objectives We performed a literature review on the prevalence of diabetes, metabolic syndrome, dyslipidemia, obesity, hypertension, and cardiovascular disease; and associated morbidity and mortality among AI/AN. Data sources A total of 203 articles were reviewed, of which 31 met study criteria for inclusion. Searches were performed on PUBMED, MEDLINE, the CDC MMWR, and the Indian Health Services. Study eligibility criteria Published literature that were published within the last fifteen years and provided direct comparisons between AI/AN to non-AI/AN populations were included. Study appraisal and synthesis methods We abstracted data on study design, data source, AI/AN population, comparison group, and. outcome measures. A descriptive synthesis of primary findings is included. Results Rates of obesity, diabetes, cardiovascular disease, and metabolic syndrome are clearly higher for AI/AN populations. Hypertension and hyperlipidemia differences are more equivocal. Our analysis also revealed that there are likely regional and gender differences in the degree of disparities observed. Limitations Studies using BRFSS telephone surveys administered in English may underestimate disparities. Many AI/AN do not have telephones and/or speak English. Regional variability makes national surveys difficult to interpret. Finally, studies using self-reported data may not be accurate. Conclusions and implications of key findings Profound health disparities in cardiovascular diseases and associated risk factors for AI/AN populations persist, perhaps due to low socioeconomic status and access to quality healthcare. Successful programs will address social determinants and increase healthcare access. Community-based outreach to bring health services to the most vulnerable may also be very helpful in this effort. Systematic review registration number N/A PMID:24454685
DOE Office of Scientific and Technical Information (OSTI.GOV)
Peterson, E.
1979-01-01
The socioeconomic studies of the present plant site community and fuelwood harvest region include the following: population, housing, income and employment, education, community services, health and social services, crime, and economic base. The potential plant impacts on the following are discussed: employment, income, state revenues, population, housing, education, community services, health services, and the wood products industry. (MHR)
ERIC Educational Resources Information Center
Pardthaisong, Tieng
The study assesses the impact of family planning programs on the fertility of women in the Chiang Mai province of Thailand, where family planning programs were introduced early in 1963. The study documents and estimates the fertility trend of Chiang Mai's population from existing sources of data. A demographic survey, in which a random sample of…
NASA Astrophysics Data System (ADS)
Heard, Victoria; Warwick, Robert
2012-09-01
We report a study of the extended X-ray emission observed in the Galactic Centre (GC) region based on archival XMM-Newton data. The GC diffuse emission can be decomposed into three distinct components: the emission from low-luminosity point sources; the fluorescence of (and reflection from) dense molecular material; and soft (kT ~1 keV), diffuse thermal plasma emission most likely energised by supernova explosions. Here, we examine the emission due to unresolved point sources. We show that this source component accounts for the bulk of the 6.7-keV and 6.9-keV line emission. We fit the surface brightness distribution evident in these lines with an empirical 2-d model, which we then compare with a prediction derived from a 3-d mass model for the old stellar population in the GC region. We find that the X-ray surface brightness declines more rapidly with angular offset from Sgr A* than the mass-model prediction. One interpretation is that the X-ray luminosity per solar mass characterising the GC source population is increasing towards the GC. Alternatively, some refinement of the mass-distribution within the nuclear stellar disc may be required. The unresolved X-ray source population is most likely dominated by magnetic CVs. We use the X-ray observations to set constraints on the number density of such sources in the GC region. Our analysis does not support the premise that the GC is pervaded by very hot (~ 7.5 keV) thermal plasma, which is truly diffuse in nature.
Yu, Weiyu; Wardrop, Nicola A; Bain, Robert; Wright, Jim A
2017-07-01
Sustainable Development Goal (SDG) 6 has expanded the Millennium Development Goals' focus from improved drinking-water to safely managed water services. This expanded focus to include issues such as water quality requires richer monitoring data and potentially integration of datasets from different sources. Relevant data sets include water point mapping (WPM), the survey of boreholes, wells and other water points, census and household survey data. This study examined inconsistencies between population census and WPM datasets for Cambodia, Liberia and Tanzania, and identified potential barriers to integrating the two datasets to meet monitoring needs. Literatures on numbers of people served per water point were used to convert WPM data to population served by water source type per area and compared with census reports. For Cambodia and Tanzania, discrepancies with census data suggested incomplete WPM coverage. In Liberia, where the data sets were consistent, WPM-derived data on functionality, quantity and quality of drinking water were further combined with census area statistics to generate an enhanced drinking-water access measure for protected wells and springs. The process revealed barriers to integrating census and WPM data, including exclusion of water points not used for drinking by households, matching of census and WPM source types; temporal mismatches between data sources; data quality issues such as missing or implausible data values, and underlying assumptions about population served by different water point technologies. However, integration of these two data sets could be used to identify and rectify gaps in WPM coverage. If WPM databases become more complete and the above barriers are addressed, it could also be used to develop more realistic measures of household drinking-water access for monitoring. Copyright © 2017 Elsevier GmbH. All rights reserved.
Mishra, Sudhanshu; Singh, Sujeet Kumar; Munjal, Ashok Kumar; Aspi, Jouni; Goyal, Surendra Prakash
2014-01-03
In India, six landscapes and source populations that are important for long-term conservation of Bengal tigers (Panthera tigris tigris) have been identified. Except for a few studies, nothing is known regarding the genetic structure and extent of gene flow among most of the tiger populations across India as the majority of them are small, fragmented and isolated. Thus, individual-based relationships are required to understand the species ecology and biology for planning effective conservation and genetics-based individual identification has been widely used. But this needs screening and describing characteristics of microsatellite loci from DNA from good-quality sources so that the required number of loci can be selected and the genotyping error rate minimized. In the studies so far conducted on the Bengal tiger, a very small number of loci (n = 35) have been tested with high-quality source of DNA, and information on locus-specific characteristics is lacking. The use of such characteristics has been strongly recommended in the literature to minimize the error rate and by the International Society for Forensic Genetics (ISFG) for forensic purposes. Therefore, we describe for the first time locus-specific genetic and genotyping profile characteristics, crucial for population genetic studies, using high-quality source of DNA of the Bengal tiger. We screened 39 heterologous microsatellite loci (Sumatran tiger, domestic cat, Asiatic lion and snow leopard) in captive individuals (n = 8), of which 21 loci are being reported for the first time in the Bengal tiger, providing an additional choice for selection. The mean relatedness coefficient (R = -0.143) indicates that the selected tigers were unrelated. Thirty-four loci were polymorphic, with the number of alleles ranging from 2 to 7 per locus, and the remaining five loci were monomorphic. Based on the PIC values (> 0.500), and other characteristics, we suggest that 16 loci (3 to 7 alleles) be used for genetic and forensic study purposes. The probabilities of matching genotypes of unrelated individuals (3.692 × 10(-19)) and siblings (4.003 × 10(-6)) are within the values needed for undertaking studies in population genetics, relatedness, sociobiology and forensics.
Bain, Rob E S; Gundry, Stephen W; Wright, Jim A; Yang, Hong; Pedley, Steve; Bartram, Jamie K
2012-03-01
To determine how data on water source quality affect assessments of progress towards the 2015 Millennium Development Goal (MDG) target on access to safe drinking-water. Data from five countries on whether drinking-water sources complied with World Health Organization water quality guidelines on contamination with thermotolerant coliform bacteria, arsenic, fluoride and nitrates in 2004 and 2005 were obtained from the Rapid Assessment of Drinking-Water Quality project. These data were used to adjust estimates of the proportion of the population with access to safe drinking-water at the MDG baseline in 1990 and in 2008 made by the Joint Monitoring Programme for Water Supply and Sanitation, which classified all improved sources as safe. Taking account of data on water source quality resulted in substantially lower estimates of the percentage of the population with access to safe drinking-water in 2008 in four of the five study countries: the absolute reduction was 11% in Ethiopia, 16% in Nicaragua, 15% in Nigeria and 7% in Tajikistan. There was only a slight reduction in Jordan. Microbial contamination was more common than chemical contamination. The criterion used by the MDG indicator to determine whether a water source is safe can lead to substantial overestimates of the population with access to safe drinking-water and, consequently, also overestimates the progress made towards the 2015 MDG target. Monitoring drinking-water supplies by recording both access to water sources and their safety would be a substantial improvement.
Walters, Linda J.; Fernandes, Flavio C.; Ferreira, Carlos E. L.
2017-01-01
In 2004, Mytella charruana (d'Orbigny, 1842) (Mollusca: Bivalvia: Mytilidae) became established along the coast of the southeastern United States (SE-US). Using mitochondrial DNA sequencing (cytochrome c oxidase subunit I), we compared genetic variation throughout its native range in South America to its invasive range in the SE-US. Samples from the SE-US were collected in 2006 and 2010 enabling a temporal comparison to evaluate possible genetic changes of the invasive population. We addressed two questions. First, what are the potential source populations (or geographic regions) for the SE-US invasion? Second, how has genetic diversity changed between the two sampling periods within the SE-US? We identified a total of 72 haplotypes, 64 of which were isolated to geographic sites and only 8 were shared among sites. The highly structured native range provides insight into the origin of invasive populations where our results suggest that the introduced SE-US population originated from multiple source populations with the Panama region as the primary source. Additionally, our results indicate that genetic composition of the non-native populations was unchanged between the two sampling periods. Mytella charruana exhibit a significant pattern of genetic structure among natural populations, owing to biogeographic barriers that limit natural dispersal, and an ability to persist in novel habitats, owing to a suite of life-history characters that favor survival under variable conditions. Overall, this study explains why M. charruana may become an increasing threat to locations founded by anthropogenic transportation. PMID:28686694
NASA Astrophysics Data System (ADS)
Masri, Shahir; Li, Lianfa; Dang, Andy; Chung, Judith H.; Chen, Jiu-Chiuan; Fan, Zhi-Hua (Tina); Wu, Jun
2018-03-01
Airborne exposures to polycyclic aromatic hydrocarbons (PAHs) are associated with adverse health outcomes. Because personal air measurements of PAHs are labor intensive and costly, spatial PAH exposure models are useful for epidemiological studies. However, few studies provide adequate spatial coverage to reflect intra-urban variability of ambient PAHs. In this study, we collected 39-40 weekly gas-phase PAH samples in southern California twice in summer and twice in winter, 2009, in order to characterize PAH source contributions and develop spatial models that can estimate gas-phase PAH concentrations at a high resolution. A spatial mixed regression model was constructed, including such variables as roadway, traffic, land-use, vegetation index, commercial cooking facilities, meteorology, and population density. Cross validation of the model resulted in an R2 of 0.66 for summer and 0.77 for winter. Results showed higher total PAH concentrations in winter. Pyrogenic sources, such as fossil fuels and diesel exhaust, were the most dominant contributors to total PAHs. PAH sources varied by season, with a higher fossil fuel and wood burning contribution in winter. Spatial autocorrelation accounted for a substantial amount of the variance in total PAH concentrations for both winter (56%) and summer (19%). In summer, other key variables explaining the variance included meteorological factors (9%), population density (15%), and roadway length (21%). In winter, the variance was also explained by traffic density (16%). In this study, source characterization confirmed the dominance of traffic and other fossil fuel sources to total measured gas-phase PAH concentrations while a spatial exposure model identified key predictors of PAH concentrations. Gas-phase PAH source characterization and exposure estimation is of high utility to epidemiologist and policy makers interested in understanding the health impacts of gas-phase PAHs and strategies to reduce emissions.
Masri, Shahir; Li, Lianfa; Dang, Andy; Chung, Judith H; Chen, Jiu-Chiuan; Fan, Zhi-Hua Tina; Wu, Jun
2018-03-01
Airborne exposures to polycyclic aromatic hydrocarbons (PAHs) are associated with adverse health outcomes. Because personal air measurements of PAHs are labor intensive and costly, spatial PAH exposure models are useful for epidemiological studies. However, few studies provide adequate spatial coverage to reflect intra-urban variability of ambient PAHs. In this study, we collected 39-40 weekly gas-phase PAH samples in southern California twice in summer and twice in winter, 2009, in order to characterize PAH source contributions and develop spatial models that can estimate gas-phase PAH concentrations at a high resolution. A spatial mixed regression model was constructed, including such variables as roadway, traffic, land-use, vegetation index, commercial cooking facilities, meteorology, and population density. Cross validation of the model resulted in an R 2 of 0.66 for summer and 0.77 for winter. Results showed higher total PAH concentrations in winter. Pyrogenic sources, such as fossil fuels and diesel exhaust, were the most dominant contributors to total PAHs. PAH sources varied by season, with a higher fossil fuel and wood burning contribution in winter. Spatial autocorrelation accounted for a substantial amount of the variance in total PAH concentrations for both winter (56%) and summer (19%). In summer, other key variables explaining the variance included meteorological factors (9%), population density (15%), and roadway length (21%). In winter, the variance was also explained by traffic density (16%). In this study, source characterization confirmed the dominance of traffic and other fossil fuel sources to total measured gas-phase PAH concentrations while a spatial exposure model identified key predictors of PAH concentrations. Gas-phase PAH source characterization and exposure estimation is of high utility to epidemiologist and policy makers interested in understanding the health impacts of gas-phase PAHs and strategies to reduce emissions.
NASA Astrophysics Data System (ADS)
Zhang, Tianhe C.; Grill, Warren M.
2010-12-01
Deep brain stimulation (DBS) has emerged as an effective treatment for movement disorders; however, the fundamental mechanisms by which DBS works are not well understood. Computational models of DBS can provide insights into these fundamental mechanisms and typically require two steps: calculation of the electrical potentials generated by DBS and, subsequently, determination of the effects of the extracellular potentials on neurons. The objective of this study was to assess the validity of using a point source electrode to approximate the DBS electrode when calculating the thresholds and spatial distribution of activation of a surrounding population of model neurons in response to monopolar DBS. Extracellular potentials in a homogenous isotropic volume conductor were calculated using either a point current source or a geometrically accurate finite element model of the Medtronic DBS 3389 lead. These extracellular potentials were coupled to populations of model axons, and thresholds and spatial distributions were determined for different electrode geometries and axon orientations. Median threshold differences between DBS and point source electrodes for individual axons varied between -20.5% and 9.5% across all orientations, monopolar polarities and electrode geometries utilizing the DBS 3389 electrode. Differences in the percentage of axons activated at a given amplitude by the point source electrode and the DBS electrode were between -9.0% and 12.6% across all monopolar configurations tested. The differences in activation between the DBS and point source electrodes occurred primarily in regions close to conductor-insulator interfaces and around the insulating tip of the DBS electrode. The robustness of the point source approximation in modeling several special cases—tissue anisotropy, a long active electrode and bipolar stimulation—was also examined. Under the conditions considered, the point source was shown to be a valid approximation for predicting excitation of populations of neurons in response to DBS.
Radiation exposure from consumer products and miscellaneous sources
DOE Office of Scientific and Technical Information (OSTI.GOV)
Not Available
1977-01-01
This review of the literature indicates that there is a variety of consumer products and miscellaneous sources of radiation that result in exposure to the U.S. population. A summary of the number of people exposed to each such source, an estimate of the resulting dose equivalents to the exposed population, and an estimate of the average annual population dose equivalent are tabulated. A review of the data in this table shows that the total average annual contribution to the whole-body dose equivalent of the U.S. population from consumer products is less than 5 mrem; about 70 percent of this arisesmore » from the presence of naturally-occurring radionuclides in building materials. Some of the consumer product sources contribute exposure mainly to localized tissues or organs. Such localized estimates include: 0.5 to 1 mrem to the average annual population lung dose equivalent (generalized); 2 rem to the average annual population bronchial epithelial dose equivalent (localized); and 10 to 15 rem to the average annual population basal mucosal dose equivalent (basal mucosa of the gum). Based on these estimates, these sources may be grouped or classified as those that involve many people and the dose equivalent is relative large or those that involve many people but the dose equivalent is relatively small, or the dose equivalent is relatively large but the number of people involved is small.« less
Kim, Sujin; Kim, Sunmi; Won, Sungho; Choi, Kyungho
2017-10-01
Epidemiological studies have shown that thyroid hormone balances can be disrupted by chemical exposure. However, many association studies have often failed to consider multiple chemicals with possible common sources of exposure, rendering their conclusions less reliable. In the 2007-2008 National Health and Nutrition Examination Survey (NHANES) from the U.S.A., urinary levels of environmental phenols, parabens, and phthalate metabolites as well as serum thyroid hormones were measured in a general U.S. population (≥12years old, n=1829). Employing these data, first, the chemicals or their metabolites associated with thyroid hormone measures were identified. Then, the chemicals/metabolites with possible common exposure sources were included in the analytical model to test the sensitivities of their association with thyroid hormone levels. Benzophenone-3 (BP-3), bisphenol A (BPA), and a metabolite of di(2-ethylhexyl) phthalate (DEHP) were identified as significant determinants of decreased serum thyroid hormones. However, significant positive correlations were detected (p-value<0.05, r=0.23 to 0.45) between these chemicals/metabolites, which suggests that they might share similar exposure sources. In the subsequent sensitivity analysis, which included the chemicals/metabolite with potentially similar exposure sources in the model, we found that urinary BP-3 and DEHP exposure were associated with decreased thyroid hormones among the general population but BPA exposure was not. In association studies, the presence of possible common exposure sources should be considered to circumvent possible false-positive conclusions. Copyright © 2017 Elsevier Ltd. All rights reserved.
Food sources of energy and nutrients in Finnish girls and boys 6-8 years of age - the PANIC study.
Eloranta, Aino-Maija; Venäläinen, Taisa; Soininen, Sonja; Jalkanen, Henna; Kiiskinen, Sanna; Schwab, Ursula; Lakka, Timo A; Lindi, Virpi
2016-01-01
Data on food sources of nutrients are needed to improve strategies to enhance nutrient intake among girls and boys in Western countries. To identify major food sources of energy, energy nutrients, dietary fibre, and micronutrients, and to study gender differences in these food sources among children. We assessed food consumption and nutrient intake using 4-day food records in a population sample of Finnish girls ( n =213) and boys ( n =217) aged 6-8 years from the Physical Activity and Nutrition in Children Study. We calculated the percentual contribution of 55 food groups for energy and nutrient intake using the population proportion method. Low-fibre grain products, skimmed milk, and high-fibre bread provided almost 23% of total energy intake. Skimmed milk was the top source of protein (18% of total intake), vitamin D (32%), potassium (20%), calcium (39%), magnesium (17%), and zinc (16%). Vegetable oils (15%) and high-fat vegetable oil-based spreads (14%) were the top sources of polyunsaturated fat. High-fibre bread was the top source of fibre (27%) and iron (12%). Non-root vegetables were the top source of folate (14%) and vitamin C (22%). Sugar-sweetened beverages provided 21% of sucrose intake. Pork was a more important source of protein and sausage was a more important source of total fat and monounsaturated fat in boys than in girls. Vegetable oils provided a higher proportion of unsaturated fat and vitamin E among boys, whereas high-fat vegetable oil-based spreads provided a higher proportion of these nutrients among girls. Commonly recommended foods, such as skimmed milk, high-fibre grain products, vegetables, vegetable oil, and vegetable oil-based spreads, were important sources of several nutrients, whereas sugar-sweetened beverages provided the majority of sucrose intake among children. This knowledge can be used in improving health among children by dietary interventions, nutrition education, and health policy decision making.
Food sources of energy and nutrients in Finnish girls and boys 6–8 years of age – the PANIC study
Eloranta, Aino-Maija; Venäläinen, Taisa; Soininen, Sonja; Jalkanen, Henna; Kiiskinen, Sanna; Schwab, Ursula; Lakka, Timo A.; Lindi, Virpi
2016-01-01
Background Data on food sources of nutrients are needed to improve strategies to enhance nutrient intake among girls and boys in Western countries. Objective To identify major food sources of energy, energy nutrients, dietary fibre, and micronutrients, and to study gender differences in these food sources among children. Design We assessed food consumption and nutrient intake using 4-day food records in a population sample of Finnish girls (n=213) and boys (n=217) aged 6–8 years from the Physical Activity and Nutrition in Children Study. We calculated the percentual contribution of 55 food groups for energy and nutrient intake using the population proportion method. Results Low-fibre grain products, skimmed milk, and high-fibre bread provided almost 23% of total energy intake. Skimmed milk was the top source of protein (18% of total intake), vitamin D (32%), potassium (20%), calcium (39%), magnesium (17%), and zinc (16%). Vegetable oils (15%) and high-fat vegetable oil–based spreads (14%) were the top sources of polyunsaturated fat. High-fibre bread was the top source of fibre (27%) and iron (12%). Non-root vegetables were the top source of folate (14%) and vitamin C (22%). Sugar-sweetened beverages provided 21% of sucrose intake. Pork was a more important source of protein and sausage was a more important source of total fat and monounsaturated fat in boys than in girls. Vegetable oils provided a higher proportion of unsaturated fat and vitamin E among boys, whereas high-fat vegetable oil–based spreads provided a higher proportion of these nutrients among girls. Conclusion Commonly recommended foods, such as skimmed milk, high-fibre grain products, vegetables, vegetable oil, and vegetable oil–based spreads, were important sources of several nutrients, whereas sugar-sweetened beverages provided the majority of sucrose intake among children. This knowledge can be used in improving health among children by dietary interventions, nutrition education, and health policy decision making. PMID:27702428
Identification of Cu’s sources in Jiaozhou Bay
NASA Astrophysics Data System (ADS)
Yang, Dongfang; Li, Haixia; Ding, Jun; Zhang, Longlei; Li, Jiangmin
2017-12-01
Many marine bays have been polluted by Cu along with the rapid development of industry, economy and population size, and identification the sources of Cu is essential to environmental protection. This paper identified the sources of Cu in according to the horizontal distribution in Jiaozhou Bay during 1982-1986. Results showed that there were five Cu sources during study years including marine current, stream flow, island top, overland runoff and marine traffic, respectively. These findings were helpful information in decision-making of pollution control and environmental remediation practice.
Enrico A. Ruíz; Jane L. Hayes; John E. Rinehart; G. Zúñiga
2007-01-01
Population genetic structure studies made in genus Dendroctonus have been conducted from the perspectives of allopatric and sympatric models. In the first case, host effect and historical contingency were not recognized as a source of variation, while the later considered the host itself as a source of reproductive isolation. Nevertheless, both...
USDA-ARS?s Scientific Manuscript database
New sources of genetic diversity must to be incorporated into plant breeding programs if they are to continue increasing grain yield and quality, and tolerance to abiotic and biotic stresses. Germplasm collections provide a source of genetic and phenotypic diversity, but characterization of these re...
Source-Sink Colonization as a Possible Strategy of Insects Living in Temporary Habitats.
Frouz, Jan; Kindlmann, Pavel
2015-01-01
Continuous colonization and re-colonization is critical for survival of insect species living in temporary habitats. When insect populations in temporary habitats are depleted, some species may escape extinction by surviving in permanent, but less suitable habitats, in which long-term population survival can be maintained only by immigration from other populations. Such situation has been repeatedly described in nature, but conditions when and how this occurs and how important this phenomenon is for insect metapopulation survival are still poorly known, mainly because it is difficult to study experimentally. Therefore, we used a simulation model to investigate, how environmental stochasticity, growth rate and the incidence of dispersal affect the positive effect of permanent but poor ("sink") habitats on the likelihood of metapopulation persistence in a network of high quality but temporary ("source") habitats. This model revealed that permanent habitats substantially increase the probability of metapopulation persistence of insect species with poor dispersal ability if the availability of temporary habitats is spatio-temporally synchronized. Addition of permanent habitats to a system sometimes enabled metapopulation persistence even in cases in which the metapopulation would otherwise go extinct, especially for species with high growth rates. For insect species with low growth rates the probability of a metapopulation persistence strongly depended on the proportions of "source" to "source" and "sink" to "source" dispersal rates.
Higuchi, P; Silva, A C; Louzada, J N C; Machado, E L M
2010-05-01
The objectives of this study were to evaluate the influence of propagules source and the implication of tree size class on the spatial pattern of Xylopia brasiliensis Spreng. individuals growing under the canopy of an experimental plantation of eucalyptus. To this end, all individuals of Xylopia brasiliensis with diameter at soil height (dsh) > 1 cm were mapped in the understory of a 3.16 ha Eucalyptus spp. and Corymbia spp. plantation, located in the municipality of Lavras, SE Brazil. The largest nearby mature tree of X. brasiliensis was considered as the propagules source. Linear regressions were used to assess the influence of the distance of propagules source on the population parameters (density, basal area and height). The spatial pattern of trees was assessed through the Ripley K function. The overall pattern showed that the propagules source distance had strong influence over spatial distribution of trees, mainly the small ones, indicating that the closer the distance from the propagules source, the higher the tree density and the lower the mean tree height. The population showed different spatial distribution patterns according to the spatial scale and diameter class considered. While small trees tended to be aggregated up to around 80 m, the largest individuals were randomly distributed in the area. A plausible explanation for observed patterns might be limited seed rain and intra-population competition.
NASA Astrophysics Data System (ADS)
Alam, Md Jahangir; Goodall, Jonathan L.
2012-04-01
The goal of this research was to quantify the relative impact of hydrologic and nitrogen source changes on incremental nitrogen yield in the contiguous United States. Using nitrogen source estimates from various federal data bases, remotely sensed land use data from the National Land Cover Data program, and observed instream loadings from the United States Geological Survey National Stream Quality Accounting Network program, we calibrated and applied the spatially referenced regression model SPARROW to estimate incremental nitrogen yield for the contiguous United States. We ran different model scenarios to separate the effects of changes in source contributions from hydrologic changes for the years 1992 and 2001, assuming that only state conditions changed and that model coefficients describing the stream water-quality response to changes in state conditions remained constant between 1992 and 2001. Model results show a decrease of 8.2% in the median incremental nitrogen yield over the period of analysis with the vast majority of this decrease due to changes in hydrologic conditions rather than decreases in nitrogen sources. For example, when we changed the 1992 version of the model to have nitrogen source data from 2001, the model results showed only a small increase in median incremental nitrogen yield (0.12%). However, when we changed the 1992 version of the model to have hydrologic conditions from 2001, model results showed a decrease of approximately 8.7% in median incremental nitrogen yield. We did, however, find notable differences in incremental yield estimates for different sources of nitrogen after controlling for hydrologic changes, particularly for population related sources. For example, the median incremental yield for population related sources increased by 8.4% after controlling for hydrologic changes. This is in contrast to a 2.8% decrease in population related sources when hydrologic changes are included in the analysis. Likewise we found that median incremental yield from urban watersheds increased by 6.8% after controlling for hydrologic changes—in contrast to the median incremental nitrogen yield from cropland watersheds, which decreased by 2.1% over the same time period. These results suggest that, after accounting for hydrologic changes, population related sources became a more significant contributor of nitrogen yield to streams in the contiguous United States over the period of analysis. However, this study was not able to account for the influence of human management practices such as improvements in wastewater treatment plants or Best Management Practices that likely improved water quality, due to a lack of data for quantifying the impact of these practices for the study area.
ERIC Educational Resources Information Center
Psacharopoulos, George, Ed.; Patrinos, Harry Anthony, Ed.
The indigenous peoples of Latin America live in conditions of extreme poverty. This book uses empirical data from national survey sources to determine the extent of poverty among Latin American indigenous populations; to compare indigenous and nonindigenous populations with regard to socioeconomic status, living conditions, educational attainment,…
USDA-ARS?s Scientific Manuscript database
The correct identification of the source population of an invasive species is a prerequisite for defining and testing different hypotheses concerning the environmental and evolutionary factors responsible for biological invasions. The native area of invasive species may be large, barely known and/or...
Observational studies of patients in the emergency department: a comparison of 4 sampling methods.
Valley, Morgan A; Heard, Kennon J; Ginde, Adit A; Lezotte, Dennis C; Lowenstein, Steven R
2012-08-01
We evaluate the ability of 4 sampling methods to generate representative samples of the emergency department (ED) population. We analyzed the electronic records of 21,662 consecutive patient visits at an urban, academic ED. From this population, we simulated different models of study recruitment in the ED by using 2 sample sizes (n=200 and n=400) and 4 sampling methods: true random, random 4-hour time blocks by exact sample size, random 4-hour time blocks by a predetermined number of blocks, and convenience or "business hours." For each method and sample size, we obtained 1,000 samples from the population. Using χ(2) tests, we measured the number of statistically significant differences between the sample and the population for 8 variables (age, sex, race/ethnicity, language, triage acuity, arrival mode, disposition, and payer source). Then, for each variable, method, and sample size, we compared the proportion of the 1,000 samples that differed from the overall ED population to the expected proportion (5%). Only the true random samples represented the population with respect to sex, race/ethnicity, triage acuity, mode of arrival, language, and payer source in at least 95% of the samples. Patient samples obtained using random 4-hour time blocks and business hours sampling systematically differed from the overall ED patient population for several important demographic and clinical variables. However, the magnitude of these differences was not large. Common sampling strategies selected for ED-based studies may affect parameter estimates for several representative population variables. However, the potential for bias for these variables appears small. Copyright © 2012. Published by Mosby, Inc.
Barrès, B; Carlier, J; Seguin, M; Fenouillet, C; Cilas, C; Ravigné, V
2012-01-01
Understanding the processes by which new diseases are introduced in previously healthy areas is of major interest in elaborating prevention and management policies, as well as in understanding the dynamics of pathogen diversity at large spatial scale. In this study, we aimed to decipher the dispersal processes that have led to the emergence of the plant pathogenic fungus Microcyclus ulei, which is responsible for the South American Leaf Blight (SALB). This fungus has devastated rubber tree plantations across Latin America since the beginning of the twentieth century. As only imprecise historical information is available, the study of population evolutionary history based on population genetics appeared most appropriate. The distribution of genetic diversity in a continental sampling of four countries (Brazil, Ecuador, Guatemala and French Guiana) was studied using a set of 16 microsatellite markers developed specifically for this purpose. A very strong genetic structure was found (Fst=0.70), demonstrating that there has been no regular gene flow between Latin American M. ulei populations. Strong bottlenecks probably occurred at the foundation of each population. The most likely scenario of colonization identified by the Approximate Bayesian Computation (ABC) method implemented in 𝒟ℐ𝒴𝒜ℬ𝒞 suggested two independent sources from the Amazonian endemic area. The Brazilian, Ecuadorian and Guatemalan populations might stem from serial introductions through human-mediated movement of infected plant material from an unsampled source population, whereas the French Guiana population seems to have arisen from an independent colonization event through spore dispersal. PMID:22828899
Characterizing source-sink dynamics with genetic parentage assignments
M. Zachariah Peery; Steven R. Beissinger; Roger F. House; Martine Berube; Laurie A. Hall; Anna Sellas; Per J. Palsboll
2008-01-01
Source-sink dynamics have been suggested to characterize the population structure of many species, but the prevalence of source-sink systems in nature is uncertain because of inherent challenges in estimating migration rates among populations. Migration rates are often difficult to estimate directly with demographic methods, and indirect genetic methods are subject to...
A Deep Chandra ACIS Survey of M51
NASA Astrophysics Data System (ADS)
Kuntz, K. D.; Long, Knox S.; Kilgard, Roy E.
2016-08-01
We have obtained a deep X-ray image of the nearby galaxy M51 using Chandra. Here we present the catalog of X-ray sources detected in these observations and provide an overview of the properties of the point-source population. We find 298 sources within the D 25 radii of NGC 5194/5, of which 20% are variable, a dozen are classical transients, and another half dozen are transient-like sources. The typical number of active ultraluminous X-ray sources in any given observation is ˜5, and only two of those sources persist in an ultraluminous state over the 12 yr of observations. Given reasonable assumptions about the supernova remnant population, the luminosity function is well described by a power law with an index between 1.55 and 1.7, only slightly shallower than that found for populations dominated by high-mass X-ray binaries (HMXBs), which suggests that the binary population in NGC 5194 is also dominated by HMXBs. The luminosity function of NGC 5195 is more consistent with a low-mass X-ray binary dominated population. Based on observations made with NASA's Chandra X-ray Observatory, which is operated by the Smithsonian Astrophysical Observatory under contract #NAS83060, and the data were obtained through program GO1-12115.
Parker, Kathleen C; Trapnell, Dorset W; Hamrick, J L; Hodgson, Wendy C
2014-05-01
At least seven species of Agave, including A. parryi, were cultivated prehistorically in Arizona, serving as important sources of food and fibre. Many relict populations from ancient cultivation remain in the modern landscape, offering a unique opportunity to study pre-Columbian plant manipulation practices. This study examined genetic and morphological variation in six A. p. var. huachucensis populations of unknown origin to compare them with previous work on A. parryi populations of known origin, to infer their cultivation history and to determine whether artificial selection is evident in populations potentially managed by early agriculturalists. Six A. p. var. huachucensis and 17 A. parryi populations were sampled, and morphometric, allozyme and microsatellite data were used to compare morphology and genetic structure in purportedly anthropogenic and wild populations, as well as in the two taxa. Analysis of molecular variance and Bayesian clustering were performed to partition variation associated with taxonomic identity and hypothesized evolutionary history, to highlight patterns of similarity among populations and to identify potential wild sources for the planting stock. A p. var. huachucensis and A. parryi populations differed significantly both morphologically and genetically. Like A. parryi, wild A. p. var. huachucensis populations were more genetically diverse than the inferred anthropogenic populations, with greater expected heterozygosity, percentage of polymorphic loci and number of alleles. Inferred anthropogenic populations exhibited many traits indicative of past active cultivation: greater morphological uniformity, fixed heterozygosity for several loci (non-existent in wild populations), fewer multilocus genotypes and strong differentiation among populations. Where archaeological information is lacking, the genetic signature of many Agave populations in Arizona can be used to infer their evolutionary history and to identify potentially fruitful sites for archaeological investigation of ancient settlements and cultivation practices. The same approach can clearly be adopted for other species in similar situations.
Parker, Kathleen C.; Trapnell, Dorset W.; Hamrick, J. L.; Hodgson, Wendy C.
2014-01-01
Background and Aims At least seven species of Agave, including A. parryi, were cultivated prehistorically in Arizona, serving as important sources of food and fibre. Many relict populations from ancient cultivation remain in the modern landscape, offering a unique opportunity to study pre-Columbian plant manipulation practices. This study examined genetic and morphological variation in six A. p. var. huachucensis populations of unknown origin to compare them with previous work on A. parryi populations of known origin, to infer their cultivation history and to determine whether artificial selection is evident in populations potentially managed by early agriculturalists. Methods Six A. p. var. huachucensis and 17 A. parryi populations were sampled, and morphometric, allozyme and microsatellite data were used to compare morphology and genetic structure in purportedly anthropogenic and wild populations, as well as in the two taxa. Analysis of molecular variance and Bayesian clustering were performed to partition variation associated with taxonomic identity and hypothesized evolutionary history, to highlight patterns of similarity among populations and to identify potential wild sources for the planting stock. Key Results A p. var. huachucensis and A. parryi populations differed significantly both morphologically and genetically. Like A. parryi, wild A. p. var. huachucensis populations were more genetically diverse than the inferred anthropogenic populations, with greater expected heterozygosity, percentage of polymorphic loci and number of alleles. Inferred anthropogenic populations exhibited many traits indicative of past active cultivation: greater morphological uniformity, fixed heterozygosity for several loci (non-existent in wild populations), fewer multilocus genotypes and strong differentiation among populations. Conclusions Where archaeological information is lacking, the genetic signature of many Agave populations in Arizona can be used to infer their evolutionary history and to identify potentially fruitful sites for archaeological investigation of ancient settlements and cultivation practices. The same approach can clearly be adopted for other species in similar situations. PMID:24638822
Can the source–sink hypothesis explain macrofaunal abundance patterns in the abyss? A modelling test
Hardy, Sarah M.; Smith, Craig R.; Thurnherr, Andreas M.
2015-01-01
Low food availability is a major structuring force in deep-sea benthic communities, sustaining only very low densities of organisms in parts of the abyss. These low population densities may result in an Allee effect, whereby local reproductive success is inhibited, and populations are maintained by larval dispersal from bathyal slopes. This slope–abyss source–sink (SASS) hypothesis suggests that the abyssal seafloor constitutes a vast sink habitat with macrofaunal populations sustained only by an influx of larval ‘refugees' from source areas on continental slopes, where higher productivity sustains greater population densities. Abyssal macrofaunal population densities would thus be directly related to larval inputs from bathyal source populations. We evaluate three predictions derived from the SASS hypothesis: (i) slope-derived larvae can be passively transported to central abyssal regions within a single larval period, (ii) projected larval export from slopes to the abyss reproduces global patterns of macrofaunal abundance and (iii) macrofaunal abundance decreases with distance from the continental slope. We find that abyssal macrofaunal populations are unlikely to be sustained solely through influx of larvae from slope sources. Rather, local reproduction probably sustains macrofaunal populations in relatively high-productivity abyssal areas, which must also be considered as potential larval source areas for more food-poor abyssal regions. PMID:25948686
Sources, sinks, and spatial ecology of cotton mice in longleaf pine stands undergoing restoration
Sharp, N.W.; Mitchell, M.S.; Grand, J.B.
2009-01-01
The Fire and Fire Surrogate studya replicated, manipulative experimentsought the most economically and ecologically efficient way to restore the nation's fire-maintained ecosystems. As part of this study, we conducted a 3-year markrecapture study, comprising 105,000 trap-nights, to assess demographic responses of cotton mice (Peromyscus gossypinus) to Fire and Fire Surrogate treatments at the Gulf Coastal Plain site, where longleaf pine was the ecosystem to be restored. We compared competing models to evaluate restoration effects on variation in apparent survival and recruitment over time, space, and treatment, and incorporated measures of available source habitat for cotton mice with reverse-time modeling to infer immigration from outside the study area. The top-ranked survival model contained only variation over time, but the closely ranked 2nd and 3rd models included variation over space and treatment, respectively. The top 4 recruitment models all included effects for availability of source habitat and treatments. Burning appeared to degrade habitat quality for cotton mice, showing demographic characteristics of a sink, but treatments combining fire with thinning of trees or application of herbicide to the understory appeared to improve habitat quality, possibly creating sources. Bottomland hardwoods outside the study also acted as sources by providing immigrants to experimental units. Models suggested that population dynamics operated over multiple spatial scales. Treatments applied to 15-ha stands probably only caused local variation in vital rates within the larger population. ?? 2009 American Society of Mammalogists.
Open source electronic health records and chronic disease management
Goldwater, Jason C; Kwon, Nancy J; Nathanson, Ashley; Muckle, Alison E; Brown, Alexa; Cornejo, Kerri
2014-01-01
Objective To study and report on the use of open source electronic health records (EHR) to assist with chronic care management within safety net medical settings, such as community health centers (CHC). Methods and Materials The study was conducted by NORC at the University of Chicago from April to September 2010. The NORC team undertook a comprehensive environmental scan, including a literature review, a dozen key informant interviews using a semistructured protocol, and a series of site visits to CHC that currently use an open source EHR. Results Two of the sites chosen by NORC were actively using an open source EHR to assist in the redesign of their care delivery system to support more effective chronic disease management. This included incorporating the chronic care model into an CHC and using the EHR to help facilitate its elements, such as care teams for patients, in addition to maintaining health records on indigent populations, such as tuberculosis status on homeless patients. Discussion The ability to modify the open-source EHR to adapt to the CHC environment and leverage the ecosystem of providers and users to assist in this process provided significant advantages in chronic care management. Improvements in diabetes management, controlled hypertension and increases in tuberculosis vaccinations were assisted through the use of these open source systems. Conclusions The flexibility and adaptability of open source EHR demonstrated its utility and viability in the provision of necessary and needed chronic disease care among populations served by CHC. PMID:23813566
Vyncke, Bart; Perko, Tanja; Van Gorp, Baldwin
2017-03-01
The media play an important role in risk communication, providing information about accidents, both nearby and far away. Each media source has its own presentation style, which could influence how the audience perceives the presented risk. This study investigates the explanatory power of 12 information sources (traditional media, new media, social media, and interpersonal communication) for the perceived risk posed by radiation released from the damaged Fukushima nuclear power plant on respondents' own health and that of the population in general. The analysis controlled for attitude toward nuclear energy, gender, education, satisfaction with the media coverage, and duration of attention paid to the coverage. The study uses a large empirical data set from a public opinion survey, which is representative for the Belgian population with respect to six sociodemographic variables. Results show that three information sources are significant regressors of perceived health-related risk of the nuclear accident: television, interpersonal communication, and the category of miscellaneous online sources. More favorable attitudes toward nuclear power, longer attention to the coverage, and higher satisfaction with the provided information lead to lower risk perception. Taken together, the results suggest that the media can indeed have a modest influence on how the audience perceives a risk. © 2016 Society for Risk Analysis.
SOURCES OF HUMAN EXPOSURE TO AIRBORNE PAH
Personal exposures to airborne particulate polycyclic aromatic hydrocarbons (PAHs) were studied in several populations in the US, Japan, and Czech Republic. Personal exposure monitors, developed for human exposure biomonitoring studies were used to collect fine particles (<_ 1....
Polycyclic aromatic hydrocarbons in Cambodian smoked fish.
Slámová, Tereza; Fraňková, Adéla; Hubáčková, Anna; Banout, Jan
2017-12-01
More than 85% of the population in Cambodia is strongly dependent on agriculture, of which freshwater aquaculture is one of the most important sources of food production. The smoked fish represents an important source of nutrients for Cambodian population; however, it can also lead to excessive intake of polycyclic aromatic hydrocarbons (PAHs). A field survey was conducted among selected smoked fish producers near to Tonle Sap river in Kampong Chhnang province, Cambodia. The study revealed that maximal limits for benzo[a]pyrene and the sum of four PAHs given by EC 1881/2006 were exceeded 2-50 times. Such burden can lead to increased risk of development of carcinogenic diseases.
Too much of a good thing? Nitrate from nitrogen fertilizers and cancer.
Ward, Mary H
2009-01-01
Nitrate levels in water supplies have been increasing in many areas of the world; therefore, additional studies of populations with well-characterized exposures are urgently needed to further our understanding of cancer risk associated with nitrate ingestion. Future studies should assess exposure for individuals (e.g., case-control, cohort studies) in a time frame relevant to disease development, and evaluate factors affecting nitrosation. Estimating N-nitroso compounds formation via nitrate ingestion requires information on dietary and drinking water sources of nitrate, inhibitors of nitrosation (e.g., vitamin C), nitrosation precursors (e.g., red meat, nitrosatable drugs), and medical conditions that may increase nitrosation (e.g., inflammatory bowel disease). Studies should account for the potentially different effects of dietary and water sources of nitrate and should include the population using private wells for whom exposure levels are often higher than public supplies.
The “Black Box” of Prescription Drug Diversion
Inciardi, James A.; Surratt, Hilary L.; Cicero, Theodore J.; Kurtz, Steven P.; Martin, Steven S.; Parrino, Mark W.
2009-01-01
A variety of surveys and studies are examined in an effort to better understand the scope of prescription drug diversion and to determine if there are consistent patterns of diversion among various populations of prescription drug abusers. Data are drawn from the RADARS® System, the National Survey of Drug Use and Health (NSDUH), the Delaware School Survey, and a series of quantitative and qualitative studies conducted in Miami, Florida. The data suggest that the major sources of diversion include drug dealers, friends and relatives, smugglers, pain patients, and the elderly, but these vary by the population being targeted. In all of the studies examined, the use of the Internet as a source for prescription drugs is insignificant. Little is known about where drug dealers are obtaining their supplies, and as such, prescription drug diversion is a “black box” requiring concentrated systematic study. PMID:20155603
Stervander, Martin; Illera, Juan Carlos; Kvist, Laura; Barbosa, Pedro; Keehnen, Naomi P; Pruisscher, Peter; Bensch, Staffan; Hansson, Bengt
2015-05-01
Isolated islands and their often unique biota continue to play key roles for understanding the importance of drift, genetic variation and adaptation in the process of population differentiation and speciation. One island system that has inspired and intrigued evolutionary biologists is the blue tit complex (Cyanistes spp.) in Europe and Africa, in particular the complex evolutionary history of the multiple genetically distinct taxa of the Canary Islands. Understanding Afrocanarian colonization events is of particular importance because of recent unconventional suggestions that these island populations acted as source of the widespread population in mainland Africa. We investigated the relationship between mainland and island blue tits using a combination of Sanger sequencing at a population level (20 loci; 12 500 nucleotides) and next-generation sequencing of single population representatives (>3 200 000 nucleotides), analysed in coalescence and phylogenetic frameworks. We found (i) that Afrocanarian blue tits are monophyletic and represent four major clades, (ii) that the blue tit complex has a continental origin and that the Canary Islands were colonized three times, (iii) that all island populations have low genetic variation, indicating low long-term effective population sizes and (iv) that populations on La Palma and in Libya represent relicts of an ancestral North African population. Further, demographic reconstructions revealed (v) that the Canary Islands, conforming to traditional views, hold sink populations, which have not served as source for back colonization of the African mainland. Our study demonstrates the importance of complete taxon sampling and an extensive multimarker study design to obtain robust phylogeographical inferences. © 2015 John Wiley & Sons Ltd.
A visual study of chemotaxis of human lymphocytes using a collagen-gel assay.
Wilkinson, P C
1985-01-21
Time-lapse cinematography was used to study the chemotactic responsiveness of human blood lymphocytes as defined by morphological orientation and directional locomotion in gradients. At present, evidence for lymphocyte chemotaxis is indirect since neither of these essential features can be demonstrated with Boyden filter assays. Few lymphocytes direct from blood were motile, but culture in vitro for 1-3 days increased the proportion of locomotor forms to 30-40%. These cells were placed on 3-D collagen gels, and a chemotactic source was presented nearby on a small filter placed on the surface of, or within, the gel. The minority of lymphocytes that were capable of locomotion showed chemotactic responses to filters soaked in lipopolysaccharide if fresh human serum (20%), but not heat-inactivated serum, was present. Lymphocytes responded by protrusion of a lamella in the direction of the gradient source: 76% of locomotor lymphocytes showed their first orientation into the 180 degrees sector facing the source. They then moved directionally towards the source. The response to purified C5 peptides was equivocal. The locomotor lymphocytes showed a chemotactic response to supernatant fluids derived from cultures of the adherent mononuclear cell fraction from human blood (greater than 80% monocytes), judged by the same criteria. No particular lymphocyte type constituted the locomotor population. After exposure to LPS-activated serum, both T and B lymphocytes showed locomotor forms. There were slightly more T4+ cells among the locomotor population than among the population as a whole.
Hart Welsh; Karen L. Pope; Clara A. Wheeler
2008-01-01
Investigations to determine stable or source-sink animal population dynamics are challenging and often infeasible for most species due to the time and expense of mark-recapture studies and the challenge of life histories attributes that result in low detectability and low recapture probabilities. Often, managers rely solely on occupancy or relative abundance patterns...
Reichert, Brian E.; Martin, J.; Kendall, William L.; Cattau, Christopher E.; Kitchens, Wiley M.
2010-01-01
Individuals in wild populations face risks associated with both intrinsic (i.e. aging) and external (i.e. environmental) sources of mortality. Condition-dependent mortality occurs when there is an interaction between such factors; however, few studies have clearly demonstrated condition-dependent mortality and some have even argued that condition-dependent mortality does not occur in wild avian populations. Using large sample sizes (2084 individuals, 3746 re-sights) of individual-based longitudinal data collected over a 33 year period (1976-2008) on multiple cohorts, we used a capture-mark-recapture framework to model age-dependent survival in the snail kite Rostrhamus sociabilis plumbeus population in Florida. Adding to the growing amount of evidence for actuarial senescence in wild populations, we found evidence of senescent declines in survival probabilities in adult kites. We also tested the hypothesis that older kites experienced condition-dependent mortality during a range-wide drought event (2000-2002). The results provide convincing evidence that the annual survival probability of senescent kites was disproportionately affected by the drought relative to the survival probability of prime-aged adults. To our knowledge, this is the first evidence of condition-dependent mortality to be demonstrated in a wild avian population, a finding which challenges recent conclusions drawn in the literature. Our study suggests that senescence and condition-dependent mortality can affect the demography of wild avian populations. Accounting for these sources of variation may be particularly important to appropriately compute estimates of population growth rate, and probabilities of quasi-extinctions.
Exploring the Variability of the Fermi LAT Blazar Population
NASA Astrophysics Data System (ADS)
Macomb, Daryl J.; Shrader, C. R.
2014-01-01
The flux variability of the approximately 2000 point sources cataloged by the Fermi Gamma-Ray Space Telescope provide important clues to population characteristics. This is particularly true of the more than 1100 source that are likely AGN. By characterizing the intrinsic flux variability and distinguishing this variability from flaring behavior, we can better address questions of flare amplitudes, durations, recurrence times, and temporal profiles. A better understanding of the responsible physical environments, such as the scale and location of jet structures responsible for the high-energy emission, may emerge from such studies. Assessing these characteristics as a function of blazar sub-class is a further goal in order to address questions about the fundamentals of blazar AGN physics. Here we report on progress made in categorizing blazar flare behavior, and correlate these behaviors with blazar sub-type and other source parameters.
Zhang, Yimei; Li, Shuai; Wang, Fei; Chen, Zhuang; Chen, Jie; Wang, Liqun
2018-09-01
Toxicity of heavy metals from industrialization poses critical concern, and analysis of sources associated with potential human health risks is of unique significance. Assessing human health risk of pollution sources (factored health risk) concurrently in the whole and the sub region can provide more instructive information to protect specific potential victims. In this research, we establish a new expression model of human health risk based on quantitative analysis of sources contribution in different spatial scales. The larger scale grids and their spatial codes are used to initially identify the level of pollution risk, the type of pollution source and the sensitive population at high risk. The smaller scale grids and their spatial codes are used to identify the contribution of various sources of pollution to each sub region (larger grid) and to assess the health risks posed by each source for each sub region. The results of case study show that, for children (sensitive populations, taking school and residential area as major region of activity), the major pollution source is from the abandoned lead-acid battery plant (ALP), traffic emission and agricultural activity. The new models and results of this research present effective spatial information and useful model for quantifying the hazards of source categories and human health a t complex industrial system in the future. Copyright © 2018 Elsevier Ltd. All rights reserved.
X-ray Obscured AGN in the GOODS-N
NASA Astrophysics Data System (ADS)
Georgantopoulos, I.; Akylas, A.; Rovilos, E.; Xilouris, E.
2010-07-01
We explore the X-ray properties of the Dust Obscured Galaxies (DOGs) i.e. sources with f24μ / fR > 1000. This population has been proposed to contain a significant fraction of Compton-thick sources at high redshift. In particular we study the X-ray spectra of the 14 DOGS detected in the CDFN 2Ms exposure. Their stacked spectrum is flat with Γ=1±0.1 very similar to the stacked spectrum of the undetected DOGs (Γ=0.8±0.2). However, most of our X-ray detected DOGs present only moderate absorption with column densities 1022 < NH < 1024 cm-2. Only three sources (20%) present very flat spectra and are probably associated with reflection dominated Compton-thick sources. Our finding is rather at odds with papers which claim that the vast majority of DOGs are associated with Compton-thick sources. In any case, such sources at high redshift (z > 2) present limited interest for the X-ray background: the population synthesis models predict a contribution, for the z > 2 Compton-thick AGN, to the X-ray background flux at 30 keV, of less than 1 percent.
NASA Astrophysics Data System (ADS)
Link, Paul Karl; Fanning, C. Mark; Beranek, Luke P.
2005-12-01
Detrital-zircon age-spectra effectively define provenance in Holocene and Neogene fluvial sands from the Snake River system of the northern Rockies, U.S.A. SHRIMP U-Pb dates have been measured for forty-six samples (about 2700 zircon grains) of fluvial and aeolian sediment. The detrital-zircon age distributions are repeatable and demonstrate predictable longitudinal variation. By lumping multiple samples to attain populations of several hundred grains, we recognize distinctive, provenance-defining zircon-age distributions or "barcodes," for fluvial sedimentary systems of several scales, within the upper and middle Snake River system. Our detrital-zircon studies effectively define the geochronology of the northern Rocky Mountains. The composite detrital-zircon grain distribution of the middle Snake River consists of major populations of Neogene, Eocene, and Cretaceous magmatic grains plus intermediate and small grain populations of multiply recycled Grenville (˜950 to 1300 Ma) grains and Yavapai-Mazatzal province grains (˜1600 to 1800 Ma) recycled through the upper Belt Supergroup and Cretaceous sandstones. A wide range of older Paleoproterozoic and Archean grains are also present. The best-case scenario for using detrital-zircon populations to isolate provenance is when there is a point-source pluton with known age, that is only found in one location or drainage. We find three such zircon age-populations in fluvial sediments downstream from the point-source plutons: Ordovician in the southern Beaverhead Mountains, Jurassic in northern Nevada, and Oligocene in the Albion Mountains core complex of southern Idaho. Large detrital-zircon age-populations derived from regionally well-defined, magmatic or recycled sedimentary, sources also serve to delimit the provenance of Neogene fluvial systems. In the Snake River system, defining populations include those derived from Cretaceous Atlanta lobe of the Idaho batholith (80 to 100 Ma), Eocene Challis Volcanic Group and associated plutons (˜45 to 52 Ma), and Neogene rhyolitic Yellowstone-Snake River Plain volcanics (˜0 to 17 Ma). For first-order drainage basins containing these zircon-rich source terranes, or containing a point-source pluton, a 60-grain random sample is sufficient to define the dominant provenance. The most difficult age-distributions to analyze are those that contain multiple small zircon age-populations and no defining large populations. Examples of these include streams draining the Proterozoic and Paleozoic Cordilleran miogeocline in eastern Idaho and Pleistocene loess on the Snake River Plain. For such systems, large sample bases of hundreds of grains, plus the use of statistical methods, may be necessary to distinguish detrital-zircon age-spectra.
Multiple independent introductions of Plasmodium falciparum in South America
Yalcindag, Erhan; Elguero, Eric; Arnathau, Céline; Durand, Patrick; Akiana, Jean; Anderson, Timothy J.; Aubouy, Agnes; Balloux, François; Besnard, Patrick; Bogreau, Hervé; Carnevale, Pierre; D'Alessandro, Umberto; Fontenille, Didier; Gamboa, Dionicia; Jombart, Thibaut; Le Mire, Jacques; Leroy, Eric; Maestre, Amanda; Mayxay, Mayfong; Ménard, Didier; Musset, Lise; Newton, Paul N.; Nkoghé, Dieudonné; Noya, Oscar; Ollomo, Benjamin; Rogier, Christophe; Veron, Vincent; Wide, Albina; Zakeri, Sedigheh; Carme, Bernard; Legrand, Eric; Chevillon, Christine; Ayala, Francisco J.; Renaud, François; Prugnolle, Franck
2012-01-01
The origin of Plasmodium falciparum in South America is controversial. Some studies suggest a recent introduction during the European colonizations and the transatlantic slave trade. Other evidence—archeological and genetic—suggests a much older origin. We collected and analyzed P. falciparum isolates from different regions of the world, encompassing the distribution range of the parasite, including populations from sub-Saharan Africa, the Middle East, Southeast Asia, and South America. Analyses of microsatellite and SNP polymorphisms show that the populations of P. falciparum in South America are subdivided in two main genetic clusters (northern and southern). Phylogenetic analyses, as well as Approximate Bayesian Computation methods suggest independent introductions of the two clusters from African sources. Our estimates of divergence time between the South American populations and their likely sources favor a likely introduction from Africa during the transatlantic slave trade. PMID:22203975
Parasuram, Harilal; Nair, Bipin; D'Angelo, Egidio; Hines, Michael; Naldi, Giovanni; Diwakar, Shyam
2016-01-01
Local Field Potentials (LFPs) are population signals generated by complex spatiotemporal interaction of current sources and dipoles. Mathematical computations of LFPs allow the study of circuit functions and dysfunctions via simulations. This paper introduces LFPsim, a NEURON-based tool for computing population LFP activity and single neuron extracellular potentials. LFPsim was developed to be used on existing cable compartmental neuron and network models. Point source, line source, and RC based filter approximations can be used to compute extracellular activity. As a demonstration of efficient implementation, we showcase LFPs from mathematical models of electrotonically compact cerebellum granule neurons and morphologically complex neurons of the neocortical column. LFPsim reproduced neocortical LFP at 8, 32, and 56 Hz via current injection, in vitro post-synaptic N2a, N2b waves and in vivo T-C waves in cerebellum granular layer. LFPsim also includes a simulation of multi-electrode array of LFPs in network populations to aid computational inference between biophysical activity in neural networks and corresponding multi-unit activity resulting in extracellular and evoked LFP signals.
NASA Astrophysics Data System (ADS)
Frissell, N. A.; Baker, J. B. H.; Ruohoniemi, J. M.; Gerrard, A. J.; Miller, E. S.; Marini, J. P.; West, M. L.; Bristow, W. A.
2014-09-01
A climatology of daytime midlatitude medium-scale traveling ionospheric disturbances (MSTIDs) observed by the Blackstone Super Dual Auroral Radar Network (SuperDARN) radar is presented. MSTIDs were observed primarily from fall through spring. Two populations were observed: a dominant population heading southeast (centered at 147° geographic azimuth, ranging from 100° to 210°) and a secondary population heading northwest (centered at -50° azimuth, ranging from -75° to -25°). Horizontal velocities ranged from 50 to 250 m s-1 with a distribution maximum between 100 and 150 m s-1. Horizontal wavelengths ranged from 100 to 500 km with a distribution peak at 250 km, and periods between 23 and 60 min, suggesting that the MSTIDs may be consistent with thermospheric gravity waves. A local time (LT) dependence was observed such that the dominant (southeastward) population decreased in number as the day progressed until a late afternoon increase. The secondary (northwestward) population appeared only in the afternoon, possibly indicative of neutral wind effects or variability of sources. LT dependence was not observed in other parameters. Possible solar-geomagnetic and tropospheric MSTID sources were considered. The auroral electrojet (AE) index showed a correlation with MSTID statistics. Reverse ray tracing with the HINDGRATS model indicates that the dominant population has source regions over the Great Lakes and near the geomagnetic cusp, while the secondary population source region is 100 km above the Atlantic Ocean east of the Carolinas. This suggests that the dominant population may come from a region favorable to either tropospheric or geomagnetic sources, while the secondary population originates from a region favorable to secondary waves generated via lower atmospheric convection.
Correa-Velez, Ignacio; Ansari, Zahid; Sundararajan, Vijaya; Brown, Kaye; Gifford, Sandra M
2007-10-03
Hospitalisation for ambulatory care sensitive conditions (ACSHs) has become a recognised tool to measure access to primary care. Timely and effective outpatient care is highly relevant to refugee populations given the past exposure to torture and trauma, and poor access to adequate health care in their countries of origin and during flight. Little is known about ACSHs among resettled refugee populations. With the aim of examining the hypothesis that people from refugee backgrounds have higher ACSHs than people born in the country of hospitalisation, this study analysed a six-year state-wide hospital discharge dataset to estimate ACSH rates for residents born in refugee-source countries and compared them with the Australia-born population. Hospital discharge data between 1 July 1998 and 30 June 2004 from the Victorian Admitted Episodes Dataset were used to assess ACSH rates among residents born in eight refugee-source countries, and compare them with the Australia-born average. Rate ratios and 95% confidence levels were used to illustrate these comparisons. Four categories of ambulatory care sensitive conditions were measured: total, acute, chronic and vaccine-preventable. Country of birth was used as a proxy indicator of refugee status. When compared with the Australia-born population, hospitalisations for total and acute ambulatory care sensitive conditions were lower among refugee-born persons over the six-year period. Chronic and vaccine-preventable ACSHs were largely similar between the two population groups. Contrary to our hypothesis, preventable hospitalisation rates among people born in refugee-source countries were no higher than Australia-born population averages. More research is needed to elucidate whether low rates of preventable hospitalisation indicate better health status, appropriate health habits, timely and effective care-seeking behaviour and outpatient care, or overall low levels of health care-seeking due to other more pressing needs during the initial period of resettlement. It is important to unpack dimensions of health status and health care access in refugee populations through ad-hoc surveys as the refugee population is not a homogenous group despite sharing a common experience of forced displacement and violence-related trauma.
Grinberg, Alex; Midwinter, Anne C.; Marshall, Jonathan C.; Collins-Emerson, Julie M.; French, Nigel P.
2016-01-01
ABSTRACT Campylobacteriosis is one of the most important foodborne diseases worldwide and a significant health burden in New Zealand. Campylobacter jejuni is the predominant species worldwide, accounting for approximately 90% of human cases, followed by Campylobacter coli. Most studies in New Zealand have focused on C. jejuni; hence, the impact of C. coli strains on human health is not well understood. The aim of this study was to genotype C. coli isolates collected in the Manawatu region of New Zealand from clinical cases, fresh poultry meat, ruminant feces, and environmental water sources, between 2005 and 2014, to study their population structure and estimate the contribution of each source to the burden of human disease. Campylobacter isolates were identified by PCR and typed by multilocus sequence typing. C. coli accounted for 2.9% (n = 47/1,601) of Campylobacter isolates from human clinical cases, 9.6% (n = 108/1,123) from poultry, 13.4% (n = 49/364) from ruminants, and 6.4% (n = 11/171) from water. Molecular subtyping revealed 27 different sequence types (STs), of which 18 belonged to clonal complex ST-828. ST-1581 was the most prevalent C. coli sequence type isolated from both human cases (n = 12/47) and poultry (n = 44/110). When classified using cladistics, all sequence types belonged to clade 1 except ST-7774, which belonged to clade 2. ST-854, ST-1590, and ST-4009 were isolated only from human cases and fresh poultry, while ST-3232 was isolated only from human cases and ruminant sources. Modeling indicated ruminants and poultry as the main sources of C. coli human infection. IMPORTANCE We performed a molecular epidemiological study of Campylobacter coli infection in New Zealand, one of few such studies globally. This study analyzed the population genetic structure of the bacterium and included a probabilistic source attribution model covering different animal and water sources. The results are discussed in a global context. PMID:27208097
Remotely measuring populations during a crisis by overlaying two data sources.
Bharti, Nita; Lu, Xin; Bengtsson, Linus; Wetter, Erik; Tatem, Andrew J
2015-03-01
Societal instability and crises can cause rapid, large-scale movements. These movements are poorly understood and difficult to measure but strongly impact health. Data on these movements are important for planning response efforts. We retrospectively analyzed movement patterns surrounding a 2010 humanitarian crisis caused by internal political conflict in Côte d'Ivoire using two different methods. We used two remote measures, nighttime lights satellite imagery and anonymized mobile phone call detail records, to assess average population sizes as well as dynamic population changes. These data sources detect movements across different spatial and temporal scales. The two data sources showed strong agreement in average measures of population sizes. Because the spatiotemporal resolution of the data sources differed, we were able to obtain measurements on long- and short-term dynamic elements of populations at different points throughout the crisis. Using complementary, remote data sources to measure movement shows promise for future use in humanitarian crises. We conclude with challenges of remotely measuring movement and provide suggestions for future research and methodological developments. © The Author 2015. Published by Oxford University Press on behalf of Royal Society of Tropical Medicine and Hygiene.
Genetic diversity and patterns of population structure in Creole goats from the Americas.
Ginja, C; Gama, L T; Martínez, A; Sevane, N; Martin-Burriel, I; Lanari, M R; Revidatti, M A; Aranguren-Méndez, J A; Bedotti, D O; Ribeiro, M N; Sponenberg, P; Aguirre, E L; Alvarez-Franco, L A; Menezes, M P C; Chacón, E; Galarza, A; Gómez-Urviola, N; Martínez-López, O R; Pimenta-Filho, E C; da Rocha, L L; Stemmer, A; Landi, V; Delgado-Bermejo, J V
2017-06-01
Biodiversity studies are more efficient when large numbers of breeds belonging to several countries are involved, as they allow for an in-depth analysis of the within- and between-breed components of genetic diversity. A set of 21 microsatellites was used to investigate the genetic composition of 24 Creole goat breeds (910 animals) from 10 countries to estimate levels of genetic variability, infer population structure and understand genetic relationships among populations across the American continent. Three commercial transboundary breeds were included in the analyses to investigate admixture with Creole goats. Overall, the genetic diversity of Creole populations (mean number of alleles = 5.82 ± 1.14, observed heterozygosity = 0.585 ± 0.074) was moderate and slightly lower than what was detected in other studies with breeds from other regions. The Bayesian clustering analysis without prior information on source populations identified 22 breed clusters. Three groups comprised more than one population, namely from Brazil (Azul and Graúna; Moxotó and Repartida) and Argentina (Long and shorthair Chilluda, Pampeana Colorada and Angora-type goat). Substructure was found in Criolla Paraguaya. When prior information on sample origin was considered, 92% of the individuals were assigned to the source population (threshold q ≥ 0.700). Creole breeds are well-differentiated entities (mean coefficient of genetic differentiation = 0.111 ± 0.048, with the exception of isolated island populations). Dilution from admixture with commercial transboundary breeds appears to be negligible. Significant levels of inbreeding were detected (inbreeding coefficient > 0 in most Creole goat populations, P < 0.05). Our results provide a broad perspective on the extant genetic diversity of Creole goats, however further studies are needed to understand whether the observed geographical patterns of population structure may reflect the mode of goat colonization in the Americas. © 2017 Stichting International Foundation for Animal Genetics.
Murphy, Sean M.; Cox, John J.; Clark, Joseph D.; Augustine, Benjamin J.; Hast, John T.; Gibbs, Dan; Strunk, Michael; Dobey, Steven
2015-01-01
Animal reintroductions are important tools of wildlife management to restore species to their historical range, and they can also create unique opportunities to study population dynamics and genetics from founder events. We used non-invasive hair sampling in a systematic, closed-population capture-mark-recapture (CMR) study design at the Big South Fork (BSF) area in Kentucky during 2010 and Tennessee during 2012 to estimate the demographic and genetic characteristics of the black bear (Ursus americanus) population that resulted from a reintroduced founding population of 18 bears in 1998. We estimated 38 (95% CI: 31–66) and 190 (95% CI: 170–219) bears on the Kentucky and Tennessee study areas, respectively. Based on the Tennessee abundance estimate alone, the mean annual growth rate was 18.3% (95% CI: 17.4–19.5%) from 1998 to 2012. We also compared the genetic characteristics of bears sampled during 2010–2012 to bears in the population during 2000–2002, 2–4 years following reintroduction, and to the source population. We found that the level of genetic diversity since reintroduction as indicated by expected heterozygosity (HE) remained relatively constant (HE(source, 2004) = 0.763, HE(BSF, 2000–2002) = 0.729, HE(BSF, 2010–2012) = 0.712) and the effective number of breeders (NB) remained low but had increased since reintroduction in the absence of sufficient immigration (NB(BSF, 2000–2002) = 12, NB(BSF, 2010–2012) = 35). This bear population appears to be genetically isolated, but contrary to our expectations, we did not find evidence of genetic diversity loss or other deleterious genetic effects typically observed from small founder groups. We attribute that to high initial genetic diversity in the founder group combined with overlapping generations and rapid population growth. Although the population remains relatively small, the reintroduction using a small founder group appears to be demographically and genetically sustainable.
Zhang, Q.Z.; Nguyen, A.L.; Yu, W.H.; Le, A.D.
2012-01-01
Mesenchymal stem cells (MSCs) represent a heterogeneous population of progenitor cells with self-renewal and multipotent differentiation potential. Aside from their regenerative role, extensive in vitro and in vivo studies have demonstrated that MSCs are capable of potent immunomodulatory effects on a variety of innate and adaptive immune cells. In this article, we will review recent experimental studies on the characterization of a unique population of MSCs derived from human oral mucosa and gingiva, especially their immunomodulatory and anti-inflammatory functions and their application in the treatment of several in vivo models of inflammatory diseases. The ease of isolation, accessible tissue source, and rapid ex vivo expansion, with maintenance of stable stem-cell-like phenotypes, render oral mucosa- and gingiva-derived MSCs a promising alternative cell source for MSC-based therapies. PMID:22988012
ERIC Educational Resources Information Center
Gilliam, Melissa; Jagoda, Patrick; Fabiyi, Camille; Lyman, Phoebe; Wilson, Claire; Hill, Brandon; Bouris, Alida
2017-01-01
This project developed and studied "The Source," an alternate reality game (ARG) designed to foster interest and knowledge related to science, technology, engineering, and math (STEM) among youth from populations underrepresented in STEM fields. ARGs are multiplayer games that engage participants across several media such as shared…
ERIC Educational Resources Information Center
Wong, Sabrina T.; Yoo, Grace J.; Stewart, Anita L.
2005-01-01
This study explored social support domains and actual sources of support for older Chinese and Korean immigrants and compared them to the traditional domains based on mainly White, middle class populations. Fifty-two older Cantonese and Korean speaking immigrants participated in one of eight focus groups. We identified four similar domains:…
Desert Dust and Health: A Central Asian Review and Steppe Case Study.
Sternberg, Troy; Edwards, Mona
2017-11-03
In Asian deserts environmental and anthropomorphic dust is a significant health risk to rural populations. Natural sources in dry landscapes are exacerbated by human activities that increase the vulnerability to dust and dust-borne disease vectors. Today in Central and Inner Asian drylands, agriculture, mining, and rapid development contribute to dust generation and community exposure. Thorough review of limited dust investigation in the region implies but does not quantify health risks. Anthropogenic sources, such as the drying of the Aral Sea, highlight the shifting dust dynamics across the Central EurAsian steppe. In the Gobi Desert, our case study in Khanbogd, Mongolia addressed large-scale mining's potential dust risk to the health of the local population. Dust traps showed variable exposure to particulates among herder households and town residents; dust density distribution indicated that sources beyond the mine need to be considered when identifying particulate sources. Research suggests that atmospheric dust from multiple causes may enhance human particulate exposure. Greater awareness of dust in greater Central Asia reflects community concern about related health implications. Future human well-being in the region will require more thorough information on dust emissions in the changing environment.
Deaf Adolescents’ Learning of Cardiovascular Health Information: Sources and Access Challenges
Smith, Scott R.; Kushalnagar, Poorna; Hauser, Peter C.
2015-01-01
Deaf individuals have more cardiovascular risks than the general population that are believed to be related to their cardiovascular health knowledge disparities. This phenomenological study describes where 20 deaf sign language-using adolescents from Rochester, New York, many who possess many positive characteristics to support their health literacy, learn cardiovascular health information and their lived experiences accessing health information. The goal is to ultimately use this information to improve the delivery of cardiovascular health education to this population and other deaf adolescents at a higher risk for weak health literacy. Deaf bilingual researchers interviewed deaf adolescents, transcribed and coded the data, and described the findings. Five major sources of cardiovascular health information were identified including family, health education teachers, healthcare providers, printed materials, and informal sources. Despite possessing advantageous characteristics contributing to stronger health literacy, study participants described significant challenges with accessing health information from each source. They also demonstrated inconsistencies in their cardiovascular health knowledge, especially regarding heart attack, stroke, and cholesterol. These findings suggest a great need for additional public funding to research deaf adolescents’ informal health-related learning, develop accessible and culturally appropriate health surveys and health education programming, improve interpreter education, and disseminate information through social media. PMID:26048900
Desert Dust and Health: A Central Asian Review and Steppe Case Study
Sternberg, Troy; Edwards, Mona
2017-01-01
In Asian deserts environmental and anthropomorphic dust is a significant health risk to rural populations. Natural sources in dry landscapes are exacerbated by human activities that increase the vulnerability to dust and dust-borne disease vectors. Today in Central and Inner Asian drylands, agriculture, mining, and rapid development contribute to dust generation and community exposure. Thorough review of limited dust investigation in the region implies but does not quantify health risks. Anthropogenic sources, such as the drying of the Aral Sea, highlight the shifting dust dynamics across the Central EurAsian steppe. In the Gobi Desert, our case study in Khanbogd, Mongolia addressed large-scale mining’s potential dust risk to the health of the local population. Dust traps showed variable exposure to particulates among herder households and town residents; dust density distribution indicated that sources beyond the mine need to be considered when identifying particulate sources. Research suggests that atmospheric dust from multiple causes may enhance human particulate exposure. Greater awareness of dust in greater Central Asia reflects community concern about related health implications. Future human well-being in the region will require more thorough information on dust emissions in the changing environment. PMID:29099792
NASA Astrophysics Data System (ADS)
Zhang, Qianqian; Sun, Jichao; Liu, Jingtao; Huang, Guanxing; Lu, Chuan; Zhang, Yuxi
2015-11-01
Nitrate contamination of groundwater has become an environmental problem of widespread concern in China. We collected 899 groundwater samples from a rapidly urbanized area, in order to identify the main sources and driving mechanisms of groundwater nitrate contamination. The results showed that the land use has a significant effect on groundwater nitrate concentration (P < 0.001). Landfill leakage was an important source of nitrate in groundwater in the PRD (Pearl River Delta) region, since landfill yielded the highest nitrate concentration (38.14 mg/L) and the highest ratio of exceeded standard (42.50%). In this study, the driving mechanism of groundwater nitrate contamination was determined to be urban construction and the secondary and tertiary industrial development, and population growth. This study revealed that domestic wastewater and industrial wastewater were the main sources of groundwater nitrate pollution. Therefore, the priority method for relieving groundwater nitrate contamination is to control the random discharge of domestic and industrial wastewater in regions undergoing rapid urbanization. Capsule abstract. The main driving mechanism of groundwater nitrate contamination was determined to be urban construction and the secondary and tertiary industrial development, and population growth.
Zhang, Qianqian; Sun, Jichao; Liu, Jingtao; Huang, Guanxing; Lu, Chuan; Zhang, Yuxi
2015-11-01
Nitrate contamination of groundwater has become an environmental problem of widespread concern in China. We collected 899 groundwater samples from a rapidly urbanized area, in order to identify the main sources and driving mechanisms of groundwater nitrate contamination. The results showed that the land use has a significant effect on groundwater nitrate concentration (P<0.001). Landfill leakage was an important source of nitrate in groundwater in the PRD (Pearl River Delta) region, since landfill yielded the highest nitrate concentration (38.14 mg/L) and the highest ratio of exceeded standard (42.50%). In this study, the driving mechanism of groundwater nitrate contamination was determined to be urban construction and the secondary and tertiary industrial development, and population growth. This study revealed that domestic wastewater and industrial wastewater were the main sources of groundwater nitrate pollution. Therefore, the priority method for relieving groundwater nitrate contamination is to control the random discharge of domestic and industrial wastewater in regions undergoing rapid urbanization. Capsule abstract. The main driving mechanism of groundwater nitrate contamination was determined to be urban construction and the secondary and tertiary industrial development, and population growth. Copyright © 2015 Elsevier B.V. All rights reserved.
Nematode and grape rootstock interactions including an improved understanding of tolerance.
McKenry, M V; Anwar, Safdar A
2006-09-01
Sixteen cultivars of grape were screened over a two-year period in the presence or absence of 10 different nematode populations. Populations of Meloidogyne spp., Xiphinema index, and Mesocriconema xenoplax developed more rapidly and caused greater damage than populations of X. americanum and Tylenchulus semipenetrans. Populations of mixed Meloidogyne spp. having a history of feeding on grape were among the fastest developing populations. Tolerance to nematode parasitism appeared to be based on different mechanisms. Slow developing, less pathogenic nematode populations often stimulated vine growth, thus vines appeared to possess tolerance. Likewise, cultivars selected for nematode resistance often stimulated vine growth when fed upon by the nematode. However, tolerance sources that resulted from nematode resistance are vulnerable due to the occurrence of populations that break resistance mechanisms. Growth of cultivars with phylloxera (Daktalospharia vitifoliae) resistance was unchanged by the presence of nematodes, indicating that phylloxera resistance may provide a useful source of nematode relief. These and several additional sources of specific tolerance are discussed.
Nematode and Grape Rootstock Interactions Including an Improved Understanding of Tolerance
McKenry, M.V.; Anwar, Safdar A.
2006-01-01
Sixteen cultivars of grape were screened over a two-year period in the presence or absence of 10 different nematode populations. Populations of Meloidogyne spp., Xiphinema index, and Mesocriconema xenoplax developed more rapidly and caused greater damage than populations of X. americanum and Tylenchulus semipenetrans. Populations of mixed Meloidogyne spp. having a history of feeding on grape were among the fastest developing populations. Tolerance to nematode parasitism appeared to be based on different mechanisms. Slow developing, less pathogenic nematode populations often stimulated vine growth, thus vines appeared to possess tolerance. Likewise, cultivars selected for nematode resistance often stimulated vine growth when fed upon by the nematode. However, tolerance sources that resulted from nematode resistance are vulnerable due to the occurrence of populations that break resistance mechanisms. Growth of cultivars with phylloxera (Daktalospharia vitifoliae) resistance was unchanged by the presence of nematodes, indicating that phylloxera resistance may provide a useful source of nematode relief. These and several additional sources of specific tolerance are discussed. PMID:19259534
Morakinyo, Oyewale Mayowa; Adebowale, Stephen Ayo; Oloruntoba, Elizabeth Omoladun
2015-01-01
Source of potable water has implication on the population health. Availability of Improved Drinking Water Sources (IDWS) is a problem in developing countries, but variation exists across segments of the population. This study therefore examined the relationship between wealth status, sex of household head and source of potable water. The 2013 Nigeria Demographic and Health Survey data was used. A representative sample of 40,680 households was selected for the survey, with a minimum target of 943 completed interviews per state covering the entire population residing in non-institutional dwelling units in the country. Households where information on drinking water sources was not reported were excluded, thus reducing the sample to 38021. The dependent and key independent variables were IDWS and Wealth Index respectively. Data were analysed using Chi-square and binary logistic regression (α = .05). Households that used IDWS were headed by females (66.7 %) than males (58.7 %). Highest proportion of households who used IDWS was found in the rich wealth index group (76.7 %). The likelihood of using IDWS was higher in household headed by females (OR = 1.41; C.I = 1.33-1.49, p <0.001). Households that belong to rich wealth index and middle class were 5.06(C.I = 4.81-5.32, p <0.001) and 2.62(C.I = 2.46-2.78, p <0.001) respectively times more likely to IDWS than the poor. This pattern was sustained when other confounding variables were introduced into the regression equation as control. Households headed by women used improved drinking water sources than those headed by men. However, wealth index has strong influence on the strength of relationship between sex of household head and improved drinking water sources.
Dietary intake of antioxidant vitamins in healthy adults in relation to current recommended intake.
Jabłonowska-Lietz, Beata; Jarosz, Agnieszka; Nowicka, Graiyna
2013-01-01
The health benefits arising from antioxidant vitamins A, C and E are well recognised and their recommended dietary intake for the general population have been established. However, there is still a need for assessing antioxidant vitamin intake in different population groups. To assess intake of antioxidant vitamins: A, C, E and beta-carotene, and to identify their major sources in the diets of healthy subjects. The study group consisted of 182 adults; both men and women from polish population. Antioxidant vitamin dietary intake was assessed by individual 3-day records. Data were analysed using updated "Polish Food Composition Tables" and 'Dieta 5' Software. The average daily intake of antioxidant vitamins was: 1076 mg for vitamin A (including 46% of retinol and 55% of beta-carotene), 107 mg for vitamin C and 9 mg for vitamin E. Higher dietary intake of these vitamins was observed in men compared to women. The average intake ofantioxidant vitamins was found to be in recommended range, however, significant differences were observed between the lowest and the highest intake. They were related to differences in the consumption of food products recognized as major sources of vitamins A, C, E and beta-carotene in study population.
Gu, Qian; Koenig, Lane; Faerberg, Jennifer; Steinberg, Caroline Rossi; Vaz, Christopher; Wheatley, Mary P
2014-01-01
Objective To explore the impact of the Hospital Readmissions Reduction Program (HRRP) on hospitals serving vulnerable populations. Data Sources/Study Setting Medicare inpatient claims to calculate condition-specific readmission rates. Medicare cost reports and other sources to determine a hospital's share of duals, profit margin, and characteristics. Study Design Regression analyses and projections were used to estimate risk-adjusted readmission rates and financial penalties under the HRRP. Findings were compared across groups of hospitals, determined based on their share of duals, to assess differential impacts of the HRRP. Principal Findings Both patient dual-eligible status and a hospital's dual-eligible share of Medicare discharges have a positive impact on risk-adjusted hospital readmission rates. Under current Centers for Medicare and Medicaid Service methodology, which does not adjust for socioeconomic status, high-dual hospitals are more likely to have excess readmissions than low-dual hospitals. As a result, HRRP penalties will disproportionately fall on high-dual hospitals, which are more likely to have negative all-payer margins, raising concerns of unintended consequences of the program for vulnerable populations. Conclusions Policies to reduce hospital readmissions must balance the need to ensure continued access to quality care for vulnerable populations. PMID:24417309
Ali, Sajid; Gladieux, Pierre; Leconte, Marc; Gautier, Angélique; Justesen, Annemarie F.; Hovmøller, Mogens S.; Enjalbert, Jérôme; de Vallavieille-Pope, Claude
2014-01-01
Analyses of large-scale population structure of pathogens enable the identification of migration patterns, diversity reservoirs or longevity of populations, the understanding of current evolutionary trajectories and the anticipation of future ones. This is particularly important for long-distance migrating fungal pathogens such as Puccinia striiformis f.sp. tritici (PST), capable of rapid spread to new regions and crop varieties. Although a range of recent PST invasions at continental scales are well documented, the worldwide population structure and the center of origin of the pathogen were still unknown. In this study, we used multilocus microsatellite genotyping to infer worldwide population structure of PST and the origin of new invasions based on 409 isolates representative of distribution of the fungus on six continents. Bayesian and multivariate clustering methods partitioned the set of multilocus genotypes into six distinct genetic groups associated with their geographical origin. Analyses of linkage disequilibrium and genotypic diversity indicated a strong regional heterogeneity in levels of recombination, with clear signatures of recombination in the Himalayan (Nepal and Pakistan) and near-Himalayan regions (China) and a predominant clonal population structure in other regions. The higher genotypic diversity, recombinant population structure and high sexual reproduction ability in the Himalayan and neighboring regions suggests this area as the putative center of origin of PST. We used clustering methods and approximate Bayesian computation (ABC) to compare different competing scenarios describing ancestral relationship among ancestral populations and more recently founded populations. Our analyses confirmed the Middle East-East Africa as the most likely source of newly spreading, high-temperature-adapted strains; Europe as the source of South American, North American and Australian populations; and Mediterranean-Central Asian populations as the origin of South African populations. Although most geographic populations are not markedly affected by recent dispersal events, this study emphasizes the influence of human activities on recent long-distance spread of the pathogen. PMID:24465211
Chakraborty, Debojyoti; Wang, Tongli; Andre, Konrad; Konnert, Monika; Lexer, Manfred J.; Matulla, Christoph; Schueler, Silvio
2015-01-01
Identifying populations within tree species potentially adapted to future climatic conditions is an important requirement for reforestation and assisted migration programmes. Such populations can be identified either by empirical response functions based on correlations of quantitative traits with climate variables or by climate envelope models that compare the climate of seed sources and potential growing areas. In the present study, we analyzed the intraspecific variation in climate growth response of Douglas-fir planted within the non-analogous climate conditions of Central and continental Europe. With data from 50 common garden trials, we developed Universal Response Functions (URF) for tree height and mean basal area and compared the growth performance of the selected best performing populations with that of populations identified through a climate envelope approach. Climate variables of the trial location were found to be stronger predictors of growth performance than climate variables of the population origin. Although the precipitation regime of the population sources varied strongly none of the precipitation related climate variables of population origin was found to be significant within the models. Overall, the URFs explained more than 88% of variation in growth performance. Populations identified by the URF models originate from western Cascades and coastal areas of Washington and Oregon and show significantly higher growth performance than populations identified by the climate envelope approach under both current and climate change scenarios. The URFs predict decreasing growth performance at low and middle elevations of the case study area, but increasing growth performance on high elevation sites. Our analysis suggests that population recommendations based on empirical approaches should be preferred and population selections by climate envelope models without considering climatic constrains of growth performance should be carefully appraised before transferring populations to planting locations with novel or dissimilar climate. PMID:26288363
Azim, Tasnim; Khan, Sharful Islam; Haseen, Fariha; Huq, Nafisa Lira; Henning, Lars; Pervez, Md. Moshtaq; Chowdhury, Mahbub Elahi; Sarafian, Isabelle
2008-01-01
Bangladesh initiated an early response to the HIV epidemic starting in the mid-1980s. Since then, the res-ponse has been enhanced considerably, and many HIV-prevention interventions among the most at-risk populations and the general youth are being undertaken. Alongside prevention activities, gathering of data has been a key activity fostered by both the Government and individual development partners. This paper reviews available sources of data, including routine surveillance (HIV and behavioural among most at-risk populations), general population surveys, and various research studies with the aim to understand the dynamics of the HIV epidemic in Bangladesh. Available data show that the HIV epidemic is still at relatively low levels and is concentrated mainly among injecting drug users (IDUs) in Dhaka city. In addition, when the passively-reported cases were analyzed, another population group that appears to be especially vulnerable is migrant workers who leave their families and travel abroad for work. However, all sources of data confirm that risk behaviours that make individuals vulnerable to HIV are high—this is apparent within most at-risk populations and the general population (adult males and youth males and females). Based on the current activities and the sources of data, modelling exercises of the future of the HIV epidemic in Dhaka suggest that, if interventions are not enhanced further, Bangladesh is likely to start with an IDU-driven epidemic, similar to other neighbouring countries, which will then move to other population groups, including sex workers, males who have sex with males, clients of sex workers, and ultimately their families. This review reiterates the often repeated message that if Bangladesh wants to be an example of how to avert an HIV epidemic, it needs to act now using evidence-based programming. PMID:18831227
Bain, Rob ES; Wright, Jim A; Yang, Hong; Pedley, Steve; Bartram, Jamie K
2012-01-01
Abstract Objective To determine how data on water source quality affect assessments of progress towards the 2015 Millennium Development Goal (MDG) target on access to safe drinking-water. Methods Data from five countries on whether drinking-water sources complied with World Health Organization water quality guidelines on contamination with thermotolerant coliform bacteria, arsenic, fluoride and nitrates in 2004 and 2005 were obtained from the Rapid Assessment of Drinking-Water Quality project. These data were used to adjust estimates of the proportion of the population with access to safe drinking-water at the MDG baseline in 1990 and in 2008 made by the Joint Monitoring Programme for Water Supply and Sanitation, which classified all improved sources as safe. Findings Taking account of data on water source quality resulted in substantially lower estimates of the percentage of the population with access to safe drinking-water in 2008 in four of the five study countries: the absolute reduction was 11% in Ethiopia, 16% in Nicaragua, 15% in Nigeria and 7% in Tajikistan. There was only a slight reduction in Jordan. Microbial contamination was more common than chemical contamination. Conclusion The criterion used by the MDG indicator to determine whether a water source is safe can lead to substantial overestimates of the population with access to safe drinking-water and, consequently, also overestimates the progress made towards the 2015 MDG target. Monitoring drinking-water supplies by recording both access to water sources and their safety would be a substantial improvement. PMID:22461718
MSX Colors of Radio-Selected HII Regions in the Milky Way
NASA Astrophysics Data System (ADS)
Giveon, U.; Becker, R. H.; Helfand, D. J.; White, R. L.
2004-12-01
Investigation of the color properties of sources in the MSX catalog reveals two populations - a blue population composed of mainly evolved stars, masers and molecular clouds, and a red population composed mainly HII regions, planetary nebulae, and unclassified radio sources. We compare the MSX catalog to 5 GHz VLA maps of the first quadrant of the Galactic plane (350o
Herrmann, Wolfram J; Weikert, Cornelia; Bergmann, Manuela; Boeing, Heiner; Katzke, Verena A; Kaaks, Rudolf; Tiller, Daniel; Greiser, Karin Halina; Heier, Margit; Meisinger, Christa; Schmidt, Carsten Oliver; Neuhauser, Hannelore; Heidemann, Christin; Jünger, Claus; Wild, Philipp S; Schramm, Sara Helena; Jöckel, Karl-Heinz; Dörr, Marcus; Pischon, Tobias
2018-04-01
Cardiovascular and metabolic diseases are a major cause of mortality and loss of quality of life in Germany. Research into risk factors of these diseases requires large population-based cohort studies. Complete and accurate assessment of the incidence of cardiovascular and metabolic diseases is a key element for valid interpretation of the results from such studies. Our aim was to identify population-based cohort studies with incidence of cardiovascular and metabolic diseases in Germany and to summarize their methods for assessment and classification of disease endpoints, including myocardial infarction, type 2 diabetes, stroke, heart failure, and arterial hypertension. Within the framework of a workshop, representatives of the ascertained population-based cohort studies in Germany with incidence of cardiovascular or metabolic diseases were invited to present and to systematically provide information on their methods of endpoint identification. We identified eight studies from different regions in Germany with a total of 100,571 participants, aged 18-83 years at baseline. Self-reporting by study participants is the major source for further inquiries to assess disease endpoints in these studies. Most studies use additional data sources to verify the incidence of diseases, such as documents provided by the treating physician or hospital. Our results highlight the central role of self-reporting and the efforts associated with identification and verification of disease endpoints in cohort studies. They also provide a basis for future population-based studies that aim for standardized assessment of the incidence of cardiovascular and metabolic diseases.
Gaudeul, Myriam; Giraud, Tatiana; Kiss, Levente; Shykoff, Jacqui A.
2011-01-01
Background Ambrosia artemisiifolia is a North American native that has become one of the most problematic invasive plants in Europe and Asia. We studied its worldwide population genetic structure, using both nuclear and chloroplast microsatellite markers and an unprecedented large population sampling. Our goals were (i) to identify the sources of the invasive populations; (ii) to assess whether all invasive populations were founded by multiple introductions, as previously found in France; (iii) to examine how the introductions have affected the amount and structure of genetic variation in Europe; (iv) to document how the colonization of Europe proceeded; (v) to check whether populations exhibit significant heterozygote deficiencies, as previously observed. Principal Findings We found evidence for multiple introductions of A. artemisiifolia, within regions but also within populations in most parts of its invasive range, leading to high levels of diversity. In Europe, introductions probably stem from two different regions of the native area: populations established in Central Europe appear to have originated from eastern North America, and Eastern European populations from more western North America. This may result from differential commercial exchanges between these geographic regions. Our results indicate that the expansion in Europe mostly occurred through long-distance dispersal, explaining the absence of isolation by distance and the weak influence of geography on the genetic structure in this area in contrast to the native range. Last, we detected significant heterozygote deficiencies in most populations. This may be explained by partial selfing, biparental inbreeding and/or a Wahlund effect and further investigation is warranted. Conclusions This insight into the sources and pathways of common ragweed expansion may help to better understand its invasion success and provides baseline data for future studies on the evolutionary processes involved during range expansion in novel environments. PMID:21423697
Foster, Gary; Navarro-Ruan, Tamara; McEneny-King, Alanna; Edginton, Andrea N; Thabane, Lehana
2016-01-01
Background Individual pharmacokinetic assessment is a critical component of tailored prophylaxis for hemophilia patients. Population pharmacokinetics allows using individual sparse data, thus simplifying individual pharmacokinetic studies. Implementing population pharmacokinetics capacity for the hemophilia community is beyond individual reach and requires a system effort. Objective The Web-Accessible Population Pharmacokinetic Service—Hemophilia (WAPPS-Hemo) project aims to assemble a database of patient pharmacokinetic data for all existing factor concentrates, develop and validate population pharmacokinetics models, and integrate these models within a Web-based calculator for individualized pharmacokinetic estimation in patients at participating treatment centers. Methods Individual pharmacokinetic studies on factor VIII and IX concentrates will be sourced from pharmaceutical companies and independent investigators. All factor concentrate manufacturers, hemophilia treatment centers (HTCs), and independent investigators (identified via a systematic review of the literature) having on file pharmacokinetic data and willing to contribute full or sparse pharmacokinetic data will be eligible for participation. Multicompartmental modeling will be performed using a mixed-model approach for derivation and Bayesian forecasting for estimation of individual sparse data. NONMEM (ICON Development Solutions) will be used as modeling software. Results The WAPPS-Hemo research network has been launched and is currently joined by 30 HTCs from across the world. We have gathered dense individual pharmacokinetic data on 878 subjects, including several replicates, on 21 different molecules from 17 different sources. We have collected sparse individual pharmacokinetic data on 289 subjects from the participating centers through the testing phase of the WAPPS-Hemo Web interface. We have developed prototypal population pharmacokinetics models for 11 molecules. The WAPPS-Hemo website (available at www.wapps-hemo.org, version 2.4), with core functionalities allowing hemophilia treaters to obtain individual pharmacokinetic estimates on sparse data points after 1 or more infusions of a factor concentrate, was launched for use within the research network in July 2015. Conclusions The WAPPS-Hemo project and research network aims to make it easier to perform individual pharmacokinetic assessments on a reduced number of plasma samples by adoption of a population pharmacokinetics approach. The project will also gather data to substantially enhance the current knowledge about factor concentrate pharmacokinetics and sources of its variability in target populations. Trial Registration ClinicalTrials.gov NCT02061072; https://clinicaltrials.gov/ct2/show/NCT02061072 (Archived by WebCite at http://www.webcitation.org/6mRK9bKP6) PMID:27977390
Dust and human health: Chapter 15
Morman, Suzette A.; Plumlee, Geoffrey S.; Knippertz, Peter; Stuut, Jan-Berend W.
2013-01-01
It is generally accepted that exposure to fine particulate matter may increase risk for human morbidity and mortality. Until recently, population health related studies examining the effects of particulate matter on human health generally examined anthropogenic (industry and combustion by-products) sources with few studies considering contributions from natural sources. This chapter provides an overview of naturally occurring inorganic mineral dust research and associated human health ailments and some of the challenges in elucidating the etiological mechanisms responsible.
Exposure to High Fluoride Drinking Water and Risk of Dental Fluorosis in Estonia
Indermitte, Ene; Saava, Astrid; Karro, Enn
2009-01-01
The purpose of this study was to assess exposure to drinking water fluoride and evaluate the risk of dental fluorosis among the Estonian population. The study covered all 15 counties in Estonia and 93.7% of population that has access to public water supplies. In Estonia groundwater is the main source for public water supply systems in most towns and rural settlements. The content of natural fluoride in water ranges from 0.01 to 7.20 mg/L. The exposure to different fluoride levels was assessed by linking data from previous studies on drinking water quality with databases of the Health Protection Inspectorate on water suppliers and the number of water consumers in water supply systems. Exposure assessment showed that 4% of the study population had excessive exposure to fluoride, mainly in small public water supplies in western and central Estonia, where the Silurian-Ordovician aquifer system is the only source of drinking water. There is a strong correlation between natural fluoride levels and the prevalence of dental fluorosis. Risk of dental fluorosis was calculated to different fluoride exposure levels over 1.5 mg/L. PMID:19440411
Arfin-Khan, M A S; Vetter, V M S; Reshi, Z A; Dar, P A; Jentsch, A
2018-05-01
Successful germination and seedling emergence in new environments are crucial first steps in the life history of global plant invaders and thus play a key role in processes of range expansion. We examined the germination and seedling emergence success of three global plant invaders - Lupinus polyphyllus, Senecio inaequidens and Verbascum thapsus - in greenhouses and climate chambers under climate regimes corresponding to seven eco-regions. Seed materials were collected from one non-native population for L. polyphyllus and S. inaequidens, and from 12 populations for V. thapsus (six natives and six non-natives). Experimental climates had significant effects on species responses. No species germinated in the dry (humidity ≤ 50%) and cool (≤ 5 °C) experimental climates. But all species germinated and emerged in two moderately cool (12-19 °C) and in three warm (24-27 °C) experimental climates. In general, V. thapsus showed higher fitness than S. inaequidens and L. polyphyllus. The climate of the seed source region influenced responses of native and non-native populations of V. thapsus. Non-native populations of V. thapsus, originating from the warmer seed source, showed higher performance in warm experimental climates and lower performance in moderately cool experimental climates compared to native populations. Responses of V. thapsus populations were also related to precipitation of the seed source region in moderately dry experimental climates. The warm, semi-arid and humid experimental climates are suitable for the crucial first steps of invasion success for L. polyphyllus, S. inaequidens and V. thapsus. The species adaptation to its source region modified the responses of our studied plants under different experimental climates representing major eco-regions of the world. © 2018 German Society for Plant Sciences and The Royal Botanical Society of the Netherlands.
Bartels, Richard
2018-04-24
Here, themore » $$\\textit{Fermi}$$-LAT Collaboration recently presented a new catalog of gamma-ray sources located within the $$40^{\\circ} \\times 40^{\\circ}$$ region around the Galactic Center~(Ajello et al. 2017) -- the Second Fermi Inner Galaxy (2FIG) catalog. Utilizing this catalog, they analyzed models for the spatial distribution and luminosity function of sources with a pulsar-like gamma-ray spectrum. Ajello et al. 2017 v1 also claimed to detect, in addition to a disk-like population of pulsar-like sources, an approximately 7$$\\sigma$$ preference for an additional centrally concentrated population of pulsar-like sources, which they referred to as a "Galactic Bulge" population. Such a population would be of great interest, as it would support a pulsar interpretation of the gamma-ray excess that has long been observed in this region. In an effort to further explore the implications of this new source catalog, we attempted to reproduce the results presented by the $$\\textit{Fermi}$$-LAT Collaboration, but failed to do so. Mimicking as closely as possible the analysis techniques undertaken in Ajello et al. 2017, we instead find that our likelihood analysis favors a very different spatial distribution and luminosity function for these sources. Most notably, our results do not exhibit a strong preference for a "Galactic Bulge" population of pulsars. Furthermore, we find that masking the regions immediately surrounding each of the 2FIG pulsar candidates does $$\\textit{not}$$ significantly impact the spectrum or intensity of the Galactic Center gamma-ray excess. Although these results refute the claim of strong evidence for a centrally concentrated pulsar population presented in Ajello et al. 2017, they neither rule out nor provide support for the possibility that the Galactic Center excess is generated by a population of low-luminosity and currently largely unobserved pulsars.« less
DOE Office of Scientific and Technical Information (OSTI.GOV)
Bartels, Richard
Here, themore » $$\\textit{Fermi}$$-LAT Collaboration recently presented a new catalog of gamma-ray sources located within the $$40^{\\circ} \\times 40^{\\circ}$$ region around the Galactic Center~(Ajello et al. 2017) -- the Second Fermi Inner Galaxy (2FIG) catalog. Utilizing this catalog, they analyzed models for the spatial distribution and luminosity function of sources with a pulsar-like gamma-ray spectrum. Ajello et al. 2017 v1 also claimed to detect, in addition to a disk-like population of pulsar-like sources, an approximately 7$$\\sigma$$ preference for an additional centrally concentrated population of pulsar-like sources, which they referred to as a "Galactic Bulge" population. Such a population would be of great interest, as it would support a pulsar interpretation of the gamma-ray excess that has long been observed in this region. In an effort to further explore the implications of this new source catalog, we attempted to reproduce the results presented by the $$\\textit{Fermi}$$-LAT Collaboration, but failed to do so. Mimicking as closely as possible the analysis techniques undertaken in Ajello et al. 2017, we instead find that our likelihood analysis favors a very different spatial distribution and luminosity function for these sources. Most notably, our results do not exhibit a strong preference for a "Galactic Bulge" population of pulsars. Furthermore, we find that masking the regions immediately surrounding each of the 2FIG pulsar candidates does $$\\textit{not}$$ significantly impact the spectrum or intensity of the Galactic Center gamma-ray excess. Although these results refute the claim of strong evidence for a centrally concentrated pulsar population presented in Ajello et al. 2017, they neither rule out nor provide support for the possibility that the Galactic Center excess is generated by a population of low-luminosity and currently largely unobserved pulsars.« less
NASA Astrophysics Data System (ADS)
Bartels, Richard; Hooper, Dan; Linden, Tim; Mishra-Sharma, Siddharth; Rodd, Nicholas L.; Safdi, Benjamin R.; Slatyer, Tracy R.
2018-06-01
The Fermi-LAT Collaboration recently presented a new catalog of gamma-ray sources located within the 40 ° × 40 ° region around the Galactic Center Ajello et al. (2017) - the Second Fermi Inner Galaxy (2FIG) catalog. Utilizing this catalog, they analyzed models for the spatial distribution and luminosity function of sources with a pulsar-like gamma-ray spectrum. Ajello et al. (2017) v1 also claimed to detect, in addition to a disk-like population of pulsar-like sources, an approximately 7 σ preference for an additional centrally concentrated population of pulsar-like sources, which they referred to as a "Galactic Bulge" population. Such a population would be of great interest, as it would support a pulsar interpretation of the gamma-ray excess that has long been observed in this region. In an effort to further explore the implications of this new source catalog, we attempted to reproduce the results presented by the Fermi-LAT Collaboration, but failed to do so. Mimicking as closely as possible the analysis techniques undertaken in Ajello et al. (2017), we instead find that our likelihood analysis favors a very different spatial distribution and luminosity function for these sources. Most notably, our results do not exhibit a strong preference for a "Galactic Bulge" population of pulsars. Furthermore, we find that masking the regions immediately surrounding each of the 2FIG pulsar candidates does not significantly impact the spectrum or intensity of the Galactic Center gamma-ray excess. Although these results refute the claim of strong evidence for a centrally concentrated pulsar population presented in Ajello et al. (2017), they neither rule out nor provide support for the possibility that the Galactic Center excess is generated by a population of low-luminosity and currently largely unobserved pulsars. In a spirit of maximal openness and transparency, we have made our analysis code available at https://github.com/bsafdi/GCE-2FIG.
Pilote, Alex J; Donovan, Lisa A
2016-12-01
Patterns of plant stem traits are expected to align with a "fast-slow" plant economic spectrum across taxa. Although broad patterns support such tradeoffs in field studies, tests of hypothesized correlated trait evolution and adaptive differentiation are more robust when taxa relatedness and environment are taken into consideration. Here we test for correlated evolution of stem and leaf traits and their adaptive differentiation across environments in the herbaceous genus, Helianthus. Stem and leaf traits of 14 species of Helianthus (28 populations) were assessed in a common garden greenhouse study. Phylogenetically independent contrasts were used to test for evidence of correlated evolution of stem hydraulic and biomechanical properties, correlated evolution of stem and leaf traits, and adaptive differentiation associated with source habitat environments. Among stem traits, there was evidence for correlated evolution of some hydraulic and biomechanical properties, supporting an expected tradeoff between stem theoretical hydraulic efficiency and resistance to bending stress. Population differentiation for suites of stem and leaf traits was found to be consistent with a "fast-slow" resource-use axis for traits related to water transport and use. Associations of population traits with source habitat characteristics supported repeated evolution of a resource-acquisitive "drought-escape" strategy in arid environments. This study provides evidence of correlated evolution of stem and leaf traits consistent with the fast-slow spectrum of trait combinations related to water transport and use along the stem-to-leaf pathway. Correlations of traits with source habitat characteristics further indicate that the correlated evolution is associated, at least in part, with adaptive differentiation of Helianthus populations among native habitats differing in climate. © 2016 Botanical Society of America.
Launey, Sophie; Brunet, Geraldine; Guyomard, René; Davaine, Patrick
2010-01-01
Human-mediated biological invasions constitute interesting case studies to understand evolutionary processes, including the role of founder effects. Population expansion of newly introduced species can be highly dependant on barriers caused by landscape features, but identifying these barriers and their impact on genetic structure is a relatively recent concern in population genetics and ecology. Salmonid populations of the Kerguelen Islands archipelago are a favorable model system to address these questions as these populations are characterized by a simple history of introduction, little or no anthropogenic influence, and demographic monitoring since the first introductions. We analyzed genetic variation at 10 microsatellite loci in 19 populations of brown trout (Salmo trutta L.) in the Courbet Peninsula (Kerguelen Islands), where the species, introduced in 3 rivers only, has colonized the whole water system in 40 years. Despite a limited numbers of introductions, trout populations have maintained a genetic diversity comparable with what is found in hatchery or wild populations in Europe, but they are genetically structured. The main factor explaining the observed patterns of genetic diversity is the history of introductions, with each introduced population acting as a source for colonization of nearby rivers. Correlations between environmental and genetic parameters show that within each "source population" group, landscape characteristics (type of coast, accessibility of river mouth, distances between rivers, river length ...) play a role in shaping directions and rates of migration, and thus the genetic structure of the colonizing populations.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Vieira, J. D.; Crawford, T. M.; Switzer, E. R.
2010-08-10
We report the results of an 87 deg{sup 2} point-source survey centered at R.A. 5{sup h}30{sup m}, decl. -55{sup 0} taken with the South Pole Telescope at 1.4 and 2.0 mm wavelengths with arcminute resolution and milli-Jansky depth. Based on the ratio of flux in the two bands, we separate the detected sources into two populations, one consistent with synchrotron emission from active galactic nuclei and the other consistent with thermal emission from dust. We present source counts for each population from 11 to 640 mJy at 1.4 mm and from 4.4 to 800 mJy at 2.0 mm. The 2.0more » mm counts are dominated by synchrotron-dominated sources across our reported flux range; the 1.4 mm counts are dominated by synchrotron-dominated sources above {approx}15 mJy and by dust-dominated sources below that flux level. We detect 141 synchrotron-dominated sources and 47 dust-dominated sources at signal-to-noise ratio S/N >4.5 in at least one band. All of the most significantly detected members of the synchrotron-dominated population are associated with sources in previously published radio catalogs. Some of the dust-dominated sources are associated with nearby (z << 1) galaxies whose dust emission is also detected by the Infrared Astronomy Satellite. However, most of the bright, dust-dominated sources have no counterparts in any existing catalogs. We argue that these sources represent the rarest and brightest members of the population commonly referred to as submillimeter galaxies (SMGs). Because these sources are selected at longer wavelengths than in typical SMG surveys, they are expected to have a higher mean redshift distribution and may provide a new window on galaxy formation in the early universe.« less
Gasca-Pineda, Jaime; Cassaigne, Ivonne; Alonso, Rogelio A.; Eguiarte, Luis E.
2013-01-01
The amount of genetic diversity in a finite biological population mostly depends on the interactions among evolutionary forces and the effective population size (N e) as well as the time since population establishment. Because the N e estimation helps to explore population demographic history, and allows one to predict the behavior of genetic diversity through time, N e is a key parameter for the genetic management of small and isolated populations. Here, we explored an N e-based approach using a bighorn sheep population on Tiburon Island, Mexico (TI) as a model. We estimated the current (N crnt) and ancestral stable (N stbl) inbreeding effective population sizes as well as summary statistics to assess genetic diversity and the demographic scenarios that could explain such diversity. Then, we evaluated the feasibility of using TI as a source population for reintroduction programs. We also included data from other bighorn sheep and artiodactyl populations in the analysis to compare their inbreeding effective size estimates. The TI population showed high levels of genetic diversity with respect to other managed populations. However, our analysis suggested that TI has been under a genetic bottleneck, indicating that using individuals from this population as the only source for reintroduction could lead to a severe genetic diversity reduction. Analyses of the published data did not show a strict correlation between H E and N crnt estimates. Moreover, we detected that ancient anthropogenic and climatic pressures affected all studied populations. We conclude that the estimation of N crnt and N stbl are informative genetic diversity estimators and should be used in addition to summary statistics for conservation and population management planning. PMID:24147115
Frequency of Atrial Septal Aneurysms in Patients with Cerebral Ischemic Events
NASA Technical Reports Server (NTRS)
Agmon, Yoram; Khandheria, Bijoy K.; Meissner, Irene; Gentile, Federico; Whisnant, Jack P.; Sicks, JoRean D.; O'Fallon, W. Michael; Covalt, Jody L.; Wiebers, David O.; Seward, James B.
1999-01-01
Background-Atrial septal aneurysm (ASA) is a putative risk factor for cardioembolism. However, the frequency of ASA in the general population has not been adequately determined. Therefore, the frequency in patients with cerebral ischemic events, compared with the frequency in the general population, is poorly defined. We sought to determine the frequency of ASA in the general population and to compare the frequency of ASA in patients with cerebral ischemic events with the frequency in the general population. Methods and Results-The frequency of ASA in the population was determined in 363 subjects, a sample of the participants in the Stroke Prevention: Assessment of Risk in a Community study (control subjects), and was compared with the frequency in 355 age- and sex-matched patients undergoing transesophageal echocardiography in search of a cardiac source of embolism after a focal cerebral ischemic event. The proportion with ASA was 7.9% in patients versus 2.2% in control subjects (P=0.002; odds ratio of ASA, 3.65; 95% CI, 1.64 to 8.13, in patients versus control subjects). Patent foramen ovale (PFO) was detected with contrast injections in 56% of subjects with ASA. The presence of ASA predicted the presence of PFO (odds ratio of PFO, 4.57; 95% CI, 2.18 to 9.57, in subjects with versus those without ASA). In 86% of subjects with ASA and cerebral ischemia, transesophageal echocardiography did not detect an alternative source of cardioembolism other than an associated PFO. Conclusions-The prevalence of ASA based on this population-based study is 2.2%. The frequency of ASA is relatively higher in patients evaluated with transesophageal echocardiography after a cerebral ischemic event. ASA is frequently associated with PFO, suggesting paradoxical embolism as a mechanism of cardioembolism. In patients with cerebral ischemia and ASA, ASA (with or without PFO) commonly is the only potential cardioembolic source detected with transesophageal echocardiography.
Population Structure of Barley Landrace Populations and Gene-Flow with Modern Varieties
Bellucci, Elisa; Bitocchi, Elena; Rau, Domenico; Nanni, Laura; Ferradini, Nicoletta; Giardini, Alessandro; Rodriguez, Monica; Attene, Giovanna; Papa, Roberto
2013-01-01
Landraces are heterogeneous plant varieties that are reproduced by farmers as populations that are subject to both artificial and natural selection. Landraces are distinguished by farmers due to their specific traits, and different farmers often grow different populations of the same landrace. We used simple sequence repeats (SSRs) to analyse 12 barley landrace populations from Sardinia from two collections spanning 10 years. We analysed the population structure, and compared the population diversity of the landraces that were collected at field level (population). We used a representative pool of barley varieties for diversity comparisons and to analyse the effects of gene flow from modern varieties. We found that the Sardinian landraces are a distinct gene pool from those of both two-row and six-row barley varieties. There is also a low, but significant, mean level and population-dependent level of introgression from the modern varieties into the Sardinian landraces. Moreover, we show that the Sardinian landraces have the same level of gene diversity as the representative sample of modern commercial varieties grown in Italy in the last decades, even within population level. Thus, these populations represent crucial sources of germplasm that will be useful for crop improvement and for population genomics studies and association mapping, to identify genes, loci and genome regions responsible for adaptive variations. Our data also suggest that landraces are a source of valuable germplasm for sustainable agriculture in the context of future climate change, and that in-situ conservation strategies based on farmer use can preserve the genetic identity of landraces while allowing adaptation to local environments. PMID:24386303
Pang, Hauchie; Cataldi, Mariel; Allseits, Emmanuelle; Ward-Peterson, Melissa; de la Vega, Pura Rodríguez; Castro, Grettel; Acuña, Juan Manuel
2017-01-01
Abstract Immigrant minorities regularly experience higher incidence and mortality rates of cancer. Frequently, a variety of social determinants create obstacles for those individuals to get the screenings they need. This is especially true for Haitian immigrants, a particularly vulnerable immigrant population in South Florida, who have been identified as having low cancer screening rates. While Haitian immigrants have some of the lowest cancer screening rates in the country, there is little existing literature that addresses barriers to cancer screenings among the population of Little Haiti in Miami-Dade County, Florida. The objective of this study was to evaluate the association between having a regular source of healthcare and adherence to recommended cancer screenings in the Little Haiti population of Miami. This secondary analysis utilized data collected from a random-sample, population-based household survey conducted from November 2011 to December 2012 among a geographic area approximating Little Haiti in Miami-Dade County, Florida. A total of 421 households identified as Haitian. The main exposure of interest was whether households possessed a regular source of care. Three separate outcomes were considered: adherence with colorectal cancer screening, mammogram adherence, and Pap smear adherence. Analysis was limited to households who met the age criteria for each outcome of interest. Bivariate associations were examined using the chi square test and Fisher exact test. Binary logistic regression was used to estimate unadjusted and adjusted odds ratios (ORs) with 95% confidence intervals (CIs). After adjusting for the head of household's education and household insurance status, households without a regular source of care were significantly less likely to adhere with colorectal cancer screening (OR = 0.33; 95% CI: 0.14–0.80) or mammograms (OR = 0.28; 95% CI: 0.11–0.75). Households with insurance coverage gaps were significantly less likely to adhere with mammograms (OR = 0.40; 95% CI: 0.17–0.97) or Pap smears (OR = 0.28; 95% CI: 0.13–0.58). Our study explored adherence with multiple cancer screenings. We found a strong association between possessing a regular source of care and adherence with colorectal cancer screening and mammogram adherence. Targeted approaches to improving access to regular care may improve adherence to cancer screening adherence among this unique immigrant population. PMID:28796056
Lirman, Diego; Fong, Peggy
2007-06-01
Localized declines in coral condition are commonly linked to land-based sources of stressors that influence gradients of water quality, and the distance to sources of stressors is commonly used as a proxy for predicting the vulnerability and future status of reef resources. In this study, we evaluated explicitly whether proximity to shore and connections to coastal bays, two measures of potential land-based sources of disturbance, influence coral community and population structure, and the abundance, distribution, and condition of corals within patch reefs of the Florida Reef Tract. In the Florida Keys, long-term monitoring has documented significant differences in water quality along a cross-shelf gradient. Inshore habitats exhibit higher levels of nutrients (DIN and TP), TOC, turbidity, and light attenuation, and these levels decrease with increasing distance from shore and connections to tidal bays. In clear contrast to these patterns of water quality, corals on inshore patch reefs exhibited significantly higher coral cover, higher growth rates, and lower partial mortality rates than those documented in similar offshore habitats. Coral recruitment rates did not differ between inshore and offshore habitats. Corals on patch reefs closest to shore had well-spread population structures numerically dominated by intermediate to large colonies, while offshore populations showed narrower size-distributions that become increasingly positively skewed. Differences in size-structure of coral populations were attributed to faster growth and lower rates of partial mortality at inshore habitats. While the underlying causes for the favorable condition of inshore coral communities are not yet known, we hypothesize that the ability of corals to shift their trophic mode under adverse environmental conditions may be partly responsible for the observed patterns, as shown in other reef systems. This study, based on data collected from a uniform reef habitat type and coral species with diverse life-history and stress-response patterns from a heavily exploited reef system, showed that proximity to potential sources of stressors may not always prove an adequate proxy for assigning potential risks to reef health, and that hypothesized patterns of coral cover, population size-structure, growth, and mortality are not always directly related to water quality gradients.
Richmond, Jonathan Q.; Wood, Dustin A.; Stanford, James W.; Fisher, Robert N.
2014-01-01
The brown treesnake (Boiga irregularis) population on the Pacific island of Guam has reached iconic status as one of the most destructive invasive species of modern times, yet no published works have used genetic data to identify a source population. We used DNA sequence data from multiple genetic markers and coalescent-based phylogenetic methods to place the Guam population within the broader phylogeographic context of B. irregularis across its native range and tested whether patterns of genetic variation on the island are consistent with one or multiple introductions from different source populations. We also modeled a series of demographic scenarios that differed in the effective size and duration of a population bottleneck immediately following the invasion on Guam, and measured the fit of these simulations to the observed data using approximate Bayesian computation. Our results exclude the possibility of serial introductions from different source populations, and instead verify a single origin from the Admiralty Archipelago off the north coast of Papua New Guinea. This finding is consistent with the hypothesis thatB. irregularis was accidentally transported to Guam during military relocation efforts at the end of World War II. Demographic model comparisons suggest that multiple snakes were transported to Guam from the source locality, but that fewer than 10 individuals could be responsible for establishing the population. Our results also provide evidence that low genetic diversity stemming from the founder event has not been a hindrance to the ecological success of B. irregularis on Guam, and at the same time offers a unique ‘genetic opening’ to manage snake density using classical biological approaches.
Use and value of information sources by parents of child psychiatric patients.
Turner, Adrienne; Kabashi, Arta; Guthrie, Hannah; Burket, Roger; Turner, Philip
2011-06-01
With Web 2.0, the variety of information sources for parents of paediatric psychiatric patients has increased dramatically. Information use theory suggests newer sources supplement rather than supplant traditional sources of health information. This study sought to determine the use and value of traditional and emerging sources of information and whether the subjects had access to highly valued sources of information. One hundred parents indicated the use and value of six sources of information on the child's symptoms, diagnoses and treatment. The data were analyzed to determine if significant relationships existed between type of source and the use and value of the information sources. Ninety-four percent of the subjects had access to the Internet and almost half of those reported using the Social Web. Eighty-five percent had at least one high-value information source. The psychiatrist in the clinic, the Internet and the primary care physician were the most highly used and valued sources. Use of digital information sources was greater than found in other studies of similar populations. This use appears to complement rather than supplant more traditional sources. Further studies are needed to see if the negative impact of lack of Internet access is replicated. © 2011 The authors. Health Information and Libraries Journal © 2011 Health Libraries Group.
The distant red galaxy neighbour population of 1
NASA Astrophysics Data System (ADS)
Bornancini, C.; García Lambas, D.
We study the Distant Red Galaxy (DRG, J-Ks > 2.3) neighbour population of Quasi Stellar Objects (QSOs) selected from the Sloan Digital Sky Survey (SDSS) in the redshift range 1 < z < 2. We perform a similar analysis for optically obscured AGNs (i.e. with a limiting magnitude I > 24) detected in the mid-infrared (24 microns) with the Spitzer Space Telescope and a mean redshift z~2.2 in the Flamingos Extragalactic Survey (FLAMEX). We present results on the cross-correlation function of DRGs around QSOs and optically faint mid-infrared sources. The corresponding correlation length obtained for the QSO sample targets is r_0=5.4+/-1.6 Mpc. For the optically obscured galaxy sample we find r_0=8.9+/-1.4 Mpc. These results indicate that optically faint obscured sources are located in denser environment of evolved red galaxies compare to QSOs.
The Red MSX Source Survey: The Massive Young Stellar Population of Our Galaxy
NASA Astrophysics Data System (ADS)
Lumsden, S. L.; Hoare, M. G.; Urquhart, J. S.; Oudmaijer, R. D.; Davies, B.; Mottram, J. C.; Cooper, H. D. B.; Moore, T. J. T.
2013-09-01
We present the Red MSX Source survey, the largest statistically selected catalog of young massive protostars and H II regions to date. We outline the construction of the catalog using mid- and near-infrared color selection. We also discuss the detailed follow up work at other wavelengths, including higher spatial resolution data in the infrared. We show that within the adopted selection bounds we are more than 90% complete for the massive protostellar population, with a positional accuracy of the exciting source of better than 2 arcsec. We briefly summarize some of the results that can be obtained from studying the properties of the objects in the catalog as a whole; we find evidence that the most massive stars form: (1) preferentially nearer the Galactic center than the anti-center; (2) in the most heavily reddened environments, suggestive of high accretion rates; and (3) from the most massive cloud cores.
Wang, Mei-Zhen; Lai, Bai-Min; Dandekar, Ajai A; Yang, Yu-Sheng; Li, Na; Yin, Jun; Shen, Dong-Sheng
2017-08-15
Pseudomonas aeruginosa SD-1 is efficient at degrading aromatic compounds and can therefore contribute to the bioremediation of wastewater. P. aeruginosa uses quorum sensing (QS) to regulate the production of numerous secreted "public goods." In wastewater bioaugmentation applications, there are myriad nitrogen sources, and we queried whether various nitrogen sources impact the stabilities of both QS and the bacterial populations. In a laboratory strain of P. aeruginosa , PAO1, the absence of a nitrogen source has been shown to destabilize these populations through the emergence of QS mutant "cheaters." We tested the ability of SD-1 to grow in casein broth, a condition that requires QS for growth, when the nitrogen source with either NH 4 Cl, NaNO 3 , or NaNO 2 or with no added nitrogen source. There was great variability in susceptibility to invasion by QS mutant cheaters and, by extension, the stability of the SD-1 population. When grown with NH 4 Cl as an extra nitrogen source, no population collapse was observed; by contrast, two-thirds of cultures grown in the presence of NaNO 2 collapsed. In the populations that collapsed, the frequency of social cheaters exceeded 40%. NaNO 3 and NaNO 2 directly favor QS mutants of P. aeruginosa SD-1. Although the mechanism by which these nitrogen sources act is not clear, these data indicate that the metabolism of nitrogen can affect the stability of bacterial populations, an important observation for continuing industrial applications with this species. IMPORTANCE Bioaugmentation as a method to help remediate wastewater pollutant streams holds significant potential to enhance traditional methods of treatment. Addition of microbes that can catabolize organic pollutants can be an effective method to remove several toxic compounds. Such bioaugmented strains of bacteria have been shown to be susceptible to competition from the microbiota that are present in wastewater streams, limiting their potential effectiveness. Here, we show that bioaugmentation strains of bacteria might also be susceptible to invasion by social cheaters and that the nitrogen sources available in the wastewater might influence the ability of cheaters to overtake the bioaugmentation strains. Our results imply that control over the nitrogen sources in a wastewater stream or selective addition of certain nitrogen sources could help stabilize bioaugmentation strains of bacteria. Copyright © 2017 American Society for Microbiology.
Godos, Justyna; Marventano, Stefano; Mistretta, Antonio; Galvano, Fabio; Grosso, Giuseppe
2017-09-01
The aim of this study was to estimate the dietary intake and major food sources of polyphenols in the Mediterranean healthy Eating, Aging and Lifestyles (MEAL) study cohort. A total of 1937 individuals (18 + y) of urban population of Catania, Italy, completed a validated 110-item food frequency questionnaire; Phenol-Explorer database was used to estimate polyphenol intake. Mean intake of polyphenols was 663.7 mg/d; the most abundant classes were phenolic acids (362.7 mg/d) and flavonoids (258.7 mg/d). The main dietary sources of total polyphenols were nuts, followed by tea and coffee as source of flavanols and hydroxycinnamic acids, respectively, fruits (i.e. cherries were sources of anthocyanins and citrus fruits of flavanones) and vegetables (i.e. artichokes and olives were sources of flavones and spinach and beans of flavonols); chocolate, red wine and pasta contributed to flavanols and tyrosols, respectively. These findings will be useful to assess the potential benefits of foods with high polyphenol content.
McDonald, Robert I.; Weber, Katherine F.; Padowski, Julie; Boucher, Tim; Shemie, Daniel
2016-01-01
Urban water systems are impacted by land use within their source watersheds, as it affects raw water quality and thus the costs of water treatment. However, global estimates of the effect of land cover change on urban water-treatment costs have been hampered by a lack of global information on urban source watersheds. Here, we use a unique map of the urban source watersheds for 309 large cities (population > 750,000), combined with long-term data on anthropogenic land-use change in their source watersheds and data on water-treatment costs. We show that anthropogenic activity is highly correlated with sediment and nutrient pollution levels, which is in turn highly correlated with treatment costs. Over our study period (1900–2005), median population density has increased by a factor of 5.4 in urban source watersheds, whereas ranching and cropland use have increased by a factor of 3.4 and 2.0, respectively. Nearly all (90%) of urban source watersheds have had some level of watershed degradation, with the average pollutant yield of urban source watersheds increasing by 40% for sediment, 47% for phosphorus, and 119% for nitrogen. We estimate the degradation of watersheds over our study period has impacted treatment costs for 29% of cities globally, with operation and maintenance costs for impacted cities increasing on average by 53 ± 5% and replacement capital costs increasing by 44 ± 14%. We discuss why this widespread degradation might be occurring, and strategies cities have used to slow natural land cover loss. PMID:27457941
McDonald, Robert I; Weber, Katherine F; Padowski, Julie; Boucher, Tim; Shemie, Daniel
2016-08-09
Urban water systems are impacted by land use within their source watersheds, as it affects raw water quality and thus the costs of water treatment. However, global estimates of the effect of land cover change on urban water-treatment costs have been hampered by a lack of global information on urban source watersheds. Here, we use a unique map of the urban source watersheds for 309 large cities (population > 750,000), combined with long-term data on anthropogenic land-use change in their source watersheds and data on water-treatment costs. We show that anthropogenic activity is highly correlated with sediment and nutrient pollution levels, which is in turn highly correlated with treatment costs. Over our study period (1900-2005), median population density has increased by a factor of 5.4 in urban source watersheds, whereas ranching and cropland use have increased by a factor of 3.4 and 2.0, respectively. Nearly all (90%) of urban source watersheds have had some level of watershed degradation, with the average pollutant yield of urban source watersheds increasing by 40% for sediment, 47% for phosphorus, and 119% for nitrogen. We estimate the degradation of watersheds over our study period has impacted treatment costs for 29% of cities globally, with operation and maintenance costs for impacted cities increasing on average by 53 ± 5% and replacement capital costs increasing by 44 ± 14%. We discuss why this widespread degradation might be occurring, and strategies cities have used to slow natural land cover loss.
ERIC Educational Resources Information Center
Tomaskovic-Devey, Donald
This book proposes that job-level segregation by sex and race is a fundamentally important source of black-white and male-female inequalities in employment. Drawing on the North Carolina Employment and Health Survey, the first general population survey that measures the gender and racial compositions of jobs, the book explores this thesis in the…
ERIC Educational Resources Information Center
Jennings, Jerry T.
This report presents a statistical portrait of the demographic, social, and economic characteristics of American children and youth. The source of the data in U.S. government sources includes surveys, censuses, and vital statistics. In general, children are defined as persons under 14 years old, and youth as persons 14 to 24 years old. Exceptions…
USDA-ARS?s Scientific Manuscript database
In wheat (Triticum aestivum L), exotic genotypes express a broad range of spike-related traits and could be used as a source of new genes to enrich the germplasm for wheat breeding programs. In the present study, a population of 163 recombinant inbred lines derived from a cross between an elite line...
Chaturvedi, Ashutosh; Foutz, Thomas J.; McIntyre, Cameron C.
2012-01-01
Deep brain stimulation (DBS) has steadily evolved into an established surgical therapy for numerous neurological disorders, most notably Parkinson’s disease (PD). Traditional DBS technology relies on voltage-controlled stimulation with a single source; however, recent engineering advances are providing current-controlled devices with multiple independent sources. These new stimulators deliver constant current to the brain tissue, irrespective of impedance changes that occur around the electrode, and enable more specific steering of current towards targeted regions of interest. In this study, we examined the impact of current steering between multiple electrode contacts to directly activate three distinct neural populations in the subthalamic region commonly stimulated for the treatment of PD: projection neurons of the subthalamic nucleus (STN), globus pallidus internus (GPi) fibers of the lenticular fasiculus, and internal capsule (IC) fibers of passage. We used three-dimensional finite element electric field models, along with detailed multi-compartment cable models of the three neural populations to determine their activations using a wide range of stimulation parameter settings. Our results indicate that selective activation of neural populations largely depends on the location of the active electrode(s). Greater activation of the GPi and STN populations (without activating any side-effect related IC fibers) was achieved by current steering with multiple independent sources, compared to a single current source. Despite this potential advantage, it remains to be seen if these theoretical predictions result in a measurable clinical effect that outweighs the added complexity of the expanded stimulation parameter search space generated by the more flexible technology. PMID:22277548
LUMINOSITY FUNCTIONS OF LMXBs IN CENTAURUS A: GLOBULAR CLUSTERS VERSUS THE FIELD
DOE Office of Scientific and Technical Information (OSTI.GOV)
Voss, Rasmus; Gilfanov, Marat; Sivakoff, Gregory R.
2009-08-10
We study the X-ray luminosity function (XLF) of low-mass X-ray binaries (LMXB) in the nearby early-type galaxy Centaurus A, concentrating primarily on two aspects of binary populations: the XLF behavior at the low-luminosity limit and the comparison between globular cluster and field sources. The 800 ksec exposure of the deep Chandra VLP program allows us to reach a limiting luminosity of {approx}8 x 10{sup 35} erg s{sup -1}, about {approx}2-3 times deeper than previous investigations. We confirm the presence of the low-luminosity break of the overall LMXB XLF at log(L{sub X} ) {approx} 37.2-37.6, below which the luminosity distribution followsmore » a dN/d(ln L) {approx} const law. Separating globular cluster and field sources, we find a statistically significant difference between the two luminosity distributions with a relative underabundance of faint sources in the globular cluster population. This demonstrates that the samples are drawn from distinct parent populations and may disprove the hypothesis that the entire LMXB population in early-type galaxies is created dynamically in globular clusters. As a plausible explanation for this difference in the XLFs, we suggest an enhanced fraction of helium-accreting systems in globular clusters, which are created in collisions between red giants and neutron stars. Due to the four times higher ionization temperature of He, such systems are subject to accretion disk instabilities at {approx}20 times higher mass accretion rate and, therefore, are not observed as persistent sources at low luminosities.« less
Sociological research on the population awareness regarding ophthalmological care in ukraine.
Ieremeieva, Tetiana V
nowadays, there are about 45 million blind individuals and, according to the prognosis, their quantity will reach over 76 million in 2020. In such a way, nowadays ophthalmological problems become more widespread, and the market of the ophthalmological services is not studied enough to understand all the tendencies and processes. was to study the patients' awareness on eye diseases and choice peculiarities of the information sources and medical institutions among various population age groups of Lutsk, Rivne and Ternopil cities. the research was conducted as an anonymous questionnaire survey of respondents according to a specially designed integrated protocol by means of interviewing people at the streets of Lutsk (n=2000), Rivne (n=1500) and Ternopil (n=1500) cities. there was conducted a research on the population awareness concerning vision problems, analysis of social factors and peculiarities of the choice of information sources about eye diseases and factors influencing the choice of a medical institution and an ophthalmologist. It was determined that younger population prefers private medical institutions in almost half of the cases (95% confidence interval (CI) of the private institution choice probability: 0,48-0,52), while older population prefers mainly state ones (95% CI of the choice probability: 0,71-0,74). it was determined depending on the age, the range of people having vision problems varied from 22% in the "under 30 years" population group up to 76% in the "over 60 years" group, although at least 21,5% of the whole population realizing their problems do not address an ophthalmologist.
Sociological research on the population awareness regarding ophthalmological care in ukraine.
Ieremeieva, Tetiana V
2016-01-01
nowadays, there are about 45 million blind individuals and, according to the prognosis, their quantity will reach over 76 million in 2020. In such a way, nowadays ophthalmological problems become more widespread, and the market of the ophthalmological services is not studied enough to understand all the tendencies and processes. was to study the patients' awareness on eye diseases and choice peculiarities of the information sources and medical institutions among various population age groups of Lutsk, Rivne and Ternopil cities. the research was conducted as an anonymous questionnaire survey of respondents according to a specially designed integrated protocol by means of interviewing people at the streets of Lutsk (n=2000), Rivne (n=1500) and Ternopil (n=1500) cities. there was conducted a research on the population awareness concerning vision problems, analysis of social factors and peculiarities of the choice of information sources about eye diseases and factors influencing the choice of a medical institution and an ophthalmologist. It was determined that younger population prefers private medical institutions in almost half of the cases (95% confidence interval (CI) of the private institution choice probability: 0,48-0,52), while older population prefers mainly state ones (95% CI of the choice probability: 0,71-0,74). it was determined depending on the age, the range of people having vision problems varied from 22% in the "under 30 years" population group up to 76% in the "over 60 years" group, although at least 21,5% of the whole population realizing their problems do not address an ophthalmologist.
[Lead intakes by different age-sex population groups from Chinese total diet study in 2000].
Zhang, Lei; Gao, Junquan; Li, Xiaowei
2007-07-01
To estimate the dietary lead intakes by different age-sex population groups in China. The lead concentrations of food sample from 3rd Chinese total diet study were determined, and then were combined with the food consumption by population of ten age-sex groups, The lead intakes, and its distribution and dietary sources were obtained. It was found that the mean and median concentrations of lead in all food samples were 0.118 and 0.052mg/kg, respectively. The highest concentration of individual sample and mean concentrations of lead in preserved egg were 8.964mg/kg and 2.577mg/kg, respectively. The vegetable samples in Hubei Province were heavily contaminated. The lead intakes by different age-sex groups were estimated to be 54.9-112.7microg/day. The average dietary lead intakes by 2-7 years old group could reach 86.1% of PTWI, and individual lead intakes by about 30% children in this group exceed PTWI. But the average dietary lead intakes of other age-sex population groups ranged from 42.8% to 86.1% of PTWI. The main sources of dietary lead were cereals and vegetables in ten age-sex population groups, and could reach 72%-80% of total lead intakes. Although the dietary lead intakes by different age-sex population groups are all lower than PTWI, it should be decreased to a lower level. Moreover, the dietary exposures to lead are higher enough for 2-7 years old children and population in some provinces to be considered seriously.
Disparities in Oral Cancer Awareness: a Population Survey in Tehran, Iran.
Azimi, Somayyeh; Ghorbani, Zahra; Ghasemi, Erfan; Tennant, Marc; Kruger, Estie
2018-03-10
Oral cancer is a life-threatening disease with low survival rates, especially when diagnosed in an advanced stage. Lack of awareness about this cancer among the population is proposed as a possible reason for this diagnostic delay. The aim of this study was to evaluate oral cancer awareness, as well as the association of this with sociodemographic status in Tehran. In this cross-sectional population-based survey, 1800 self-administered questionnaires (collecting sociodemographic data, questions regarding oral cancer awareness and the source of information) were distributed through multistage stratified random sampling. Scores for questions ranged from 0 to 4, and totals were summed. The outcome of question responses was also analyzed separately. In total, 1312 questionnaires were available for analysis, from 788 females and 489 males (37.8 ± 9.02 years). Only 30% of the respondents were aware of oral cancer. The average score for awareness was 1.09 ± 1.6 with no significant differences between age groups and genders. Almost 6.5% of participants had complete awareness about oral cancer. A significant difference was found between mean scores in different levels of education and occupation (p = 0.0001). From 585 responses to the "source of information" question, "public media" was the most important source (almost 50%). Only 2% mentioned "dentists" as a source of information. This study indicated an alarming lack of oral cancer awareness and literacy in Tehran, Iran. Dentists should be obliged to practice their pivotal role in informing the public about oral cancer.
15-year followup of a population based prostate cancer screening study.
Kjellman, Anders; Akre, Olof; Norming, Ulf; Törnblom, Magnus; Gustafsson, Ove
2009-04-01
We evaluated long-term survival in attendees and nonattendees of a 1-time screening for prostate cancer. A total of 2,400 men 55 to 70 years old in 1988 were randomly selected and invited to a screening for prostate cancer. Of the invited men 1,782 (74%) attended. Screening attendees were examined with digital rectal examination, transrectal ultrasound and prostate specific antigen analysis. When cancer was suspected, prostate biopsies were taken. A total of 65 men with prostate cancer were detected by this procedure. The entire source population comprising 27,204 men, including 618 nonattendees (26%), was followed for prostate cancer diagnosis and survival for 15 years. Incidence rate ratios were calculated using Poisson regression models. We found no effect of this screening procedure on the risk of death from prostate cancer and other causes of death (incidence rate ratio 1.10, 95% CI 0.83-1.46 and 0.98, 95% CI 0.92-1.05, respectively) when comparing all invited men with the source population. However, attending the screening program was associated with a significantly decreased risk of death from causes other than prostate cancer (vs source population incidence rate ratio 0.82, 95% CI 0.76-0.90). In contrast, the corresponding incidence rate ratio in nonattendees was 1.53 (95% CI 1.37-1.71). We found no evidence of a beneficial effect of this specific screening procedure but strong evidence of a difference in overall survival in screening attendees and nonattendees. These findings should be considered when interpreting previous and upcoming studies of the effect of screening programs.
Voeten, Helene A C M; de Zwart, Onno; Veldhuijzen, Irene K; Yuen, Cicely; Jiang, Xinyi; Elam, Gillian; Abraham, Thomas; Brug, Johannes
2009-01-01
Ethnic minorities in Europe such as the Chinese may need a special strategy with regard to risk communication about emerging infectious diseases. To engage them in precautionary actions, it is important to know their information sources, knowledge, and health beliefs. This study's purpose is to study the use of information sources, knowledge, and health beliefs related to SARS and avian flu of Chinese people in the UK and The Netherlands, and to make comparisons with the general population in these countries. Results of a self-administered questionnaire among 300 British/Dutch Chinese were compared to data obtained from a computer-assisted phone survey among the general population (n = 800). British/Dutch Chinese got most information about emerging diseases from family and friends, followed by Chinese media and British/Dutch TV. They had less confidence than general groups in their doctor, government agencies, and consumer/patient interest groups. Their knowledge of SARS was high. They had a lower perceived threat than general populations with regard to SARS and avian flu due to a lower perceived severity. They had higher self-efficacy beliefs regarding SARS and avian flu. In case of new outbreaks of SARS/avian flu in China, local authorities in the UK and The Netherlands can best reach Chinese people through informal networks and British/Dutch TV, while trying to improve confidence in information from the government. In communications, the severity of the disease rather than the susceptibility appears to need most attention.
Warshaw, Erin M; Aschenbeck, Kelly A; Zug, Kathryn A; Belsito, Donald V; Zirwas, Matthew J; Fowler, Joseph F; Taylor, James S; Sasseville, Denis; Fransway, Anthony F; DeLeo, Vincent A; Marks, James G; Pratt, Melanie D; Maibach, Howard I; Mathias, C G Toby; DeKoven, Joel G
Although there are several case reports of wet wipe-associated contact dermatitis, the prevalence of wipes as a source of allergic contact dermatitis in larger populations and the responsible allergens are largely unknown. The aim of the study was to determine the prevalence of wet wipes as a source of contact allergy and the most commonly associated allergens in a North American tertiary referral patch test population. Data collected from 2011 to 2014 by the North American Contact Dermatitis Group was used to conduct a retrospective cross-sectional analysis of patient demographics and patch test results associated with the triple-digit source code for "wet wipe." Of the 9037 patients patch tested during the study period, 79 (0.9%) had a positive patch test reaction to an allergen identified with a wet wipe source. The most commonly associated allergens were preservatives, including the following: methylisothiazolinone (MI) (59.0%), methylchloroisothiazolinone (MCI)/MI (35.6%), bronopol (2-bromo-2-nitropropane-1,3-diol) (27.4%), and iodopropynyl butylcarbamate (12.3%). Fragrance (combined) represented 12.3%. Anal/genital dermatitis was 15 times more likely (P < 0.0001) in those with wet wipe allergy. More than 92% of patients with wipe-associated contact allergy had their contact allergens detected by the North American Contact Dermatitis Group screening series. Wet wipes are an important source of contact allergy. Preservatives are the main allergens, especially isothiazolinones.
Henry, W Brien
2013-01-15
Maize breeders continue to seek new sources of aflatoxin resistance, but most lines identified as resistance sources are late maturing. The vast difference in flowering time makes it hard to cross these lines with proprietary commercial lines that mature much earlier and often subjects the reproductive phase of these resistant lines to the hottest and driest portion of the summer, making silking, pollination and grain fill challenging. Two hundred crosses from the GEM Project were screened for aflatoxin accumulation at Mississippi State in 2008, and a subset of these lines were screened again in 2009. The breeding cross UR13085:S99g99u was identified as a potential source of aflatoxin resistance, and maturity-based selections were made from an S2 breeding population from this same germplasm source: UR13085:S99g99u-B-B. The earliest maturing selections performed poorly for aflatoxin accumulation, but later maturing selections were identified with favorable levels of aflatoxin accumulation. These selections, while designated as "late" within this study, matured earlier than most aflatoxin resistant lines presently available to breeders. Two selections from this study, designated S5_L7 and S5_L8, are potential sources of aflatoxin resistance and will be advanced for line development and additional aflatoxin screening over more site years and environments.
Giant impactors - Plausible sizes and populations
NASA Technical Reports Server (NTRS)
Hartmann, William K.; Vail, S. M.
1986-01-01
The largest sizes of planetesimals required to explain spin properties of planets are investigated in the context of the impact-trigger hypothesis of lunar origin. Solar system models with different large impactor sources are constructed and stochastic variations in obliquities and rotation periods resulting from each source are studied. The present study finds it highly plausible that earth was struck by a body of about 0.03-0.12 earth masses with enough energy and angular momentum to dislodge mantle material and form the present earth-moon system.
Pizzi, Costanza; De Stavola, Bianca L; Pearce, Neil; Lazzarato, Fulvio; Ghiotti, Paola; Merletti, Franco; Richiardi, Lorenzo
2012-11-01
Several studies have examined the effects of sample selection on the exposure-outcome association estimates in cohort studies, but the reasons why this selection may induce bias have not been fully explored. To investigate how sample selection of the web-based NINFEA birth cohort may change the confounding patterns present in the source population. The characteristics of the NINFEA participants (n=1105) were compared with those of the wider source population-the Piedmont Birth Registry (PBR)-(n=36 092), and the association of two exposures (parity and educational level) with two outcomes (low birth weight and birth by caesarean section), while controlling for other risk factors, was studied. Specifically the associations among measured risk factors within each dataset were examined and the exposure-outcome estimates compared in terms of relative ORs. The associations of educational level with the other risk factors (alcohol consumption, folic acid intake, maternal age, pregnancy weight gain, previous miscarriages) partly differed between PBR and NINFEA. This was not observed for parity. Overall, the exposure-outcome estimates derived from NINFEA only differed moderately from those obtained in PBR, with relative ORs ranging between 0.74 and 1.03. Sample selection in cohort studies may alter the confounding patterns originally present in the general population. However, this does not necessarily introduce selection bias in the exposure-outcome estimates, as sample selection may reduce some of the residual confounding present in the general population.
Mortality risks in alcoholism and effects of abstinence and addiction treatment.
Miller, N S
1999-06-01
The mortality rate from alcoholism and related comorbidities is high. Studies show multiple causes of premature death from alcoholism. Several studies showed that abstinence had a positive effective on the overall survival of alcoholics. Alcoholics who abstained from alcohol, particularly continuously, showed reduced mortality rates and increased years of longevity than alcoholics who relapsed to alcohol consumption. The sources of the findings tend to be derived from treatment populations, in which abstinence is expected to occur in higher rates than in the general population.
Jani, Andrea J.; Briggs, Cheryl J.
2018-01-01
Symbiotic microbial communities play key roles in the health and development of their multicellular hosts. Understanding why microbial communities vary among different host species or individuals is an important step toward understanding the diversity and function of the microbiome. The amphibian skin microbiome may affect resistance to the fungal pathogen Batrachochytrium dendrobatidis (Bd). Still, the factors that determine the diversity and composition of the amphibian skin microbiome, and therefore may ultimately contribute to disease resistance, are not well understood. We conducted a two-phase experiment to first test how host and environment shape the amphibian skin microbiome, and then test if the microbiome affects or is affected by Bd infection. Most lab experiments testing assembly of the amphibian skin microbiome so far have compared sterile to non-sterile environments or heavily augmented to non-augmented frogs. A goal of this study was to evaluate, in an experimental setting, realistic potential drivers of microbiome assembly that would be relevant to patterns observed in nature. We tested effects of frog genetic background (2 source populations) and 6 natural lake water sources in shaping the microbiome of the frog Rana sierrae. Water in which frogs were housed affected the microbiome in a manner that partially mimicked patterns observed in natural populations. In particular, frogs housed in water from disease-resistant populations had greater bacterial richness than frogs housed in water from populations that died out due to Bd. However, in the experiment this difference in microbiomes did not lead to differences in host mortality or rates of pathogen load increase. Frog source population also affected the microbiome and, although none of the frogs in this study showed true resistance to infection, host source population had a small effect on the rate of pathogen load increase. This difference in infection trajectories could be due to the observed differences in the microbiome, but could also be due to other traits that differ between frogs from the two populations. In addition to examining effects of the microbiome on Bd, we tested the effect of Bd infection severity on the microbiome. Specifically, we studied a time series of the microbiome over the course of infection to test if the effects of Bd on the microbiome are dependent on Bd infection severity. Although limited to a small subset of frogs, time series analysis suggested that relative abundances of several bacterial phylotypes changed as Bd loads increased through time, indicating that Bd-induced disturbance of the R. sierrae microbiome is not a binary effect but instead is dependent on infection severity. We conclude that both host and aquatic environment help shape the R. sierrae skin microbiome, with links to small changes in disease resistance in some cases, but in this study the effect of Bd on the microbiome was greater than the effect of the microbiome on Bd. Assessment of the microbiome differences between more distantly related populations than those studied here is needed to fully understand the role of the microbiome in resistance to Bd. PMID:29619014
Asymmetric impacts of two herbivore ecotypes on similar host plants
USDA-ARS?s Scientific Manuscript database
Ecotypes may arise following allopatric separation from source populations. The simultaneous transfer of an exotic plant to a novel environment, along with its stenophagous herbivore, may complicate more traditional patterns of divergence from the plant and insect source populations. We evaluated ...
Epidemiological data on shaken baby syndrome in France using judicial sources.
Tursz, Anne; Cook, Jon Mark
2014-12-01
The frequency of and risk factors for shaken baby syndrome remain poorly documented for several reasons: the real number of "benign" cases of shaken baby syndrome are not known; information sources used are diverse, there have been changes over time in the definition of this pathology and few population-based epidemiological studies are available. Estimate the frequency of fatal shaken baby syndrome and determine its risk factors through research carried out on fatal cases in three regions of France while comparing them to data from international publications. A retrospective epidemiological study of all cases of fatal shaken baby syndrome affecting infants younger than 1 year of age who were examined by the courts during a 5-year period in a defined geographical area. Shaken baby syndrome cases were compared with infanticide cases for risk factors and a comparison was made of family characteristics with those of the general population. Thirty-seven cases of shaken baby syndrome were recorded (a rate of 2.9 for 100,000 live births). As in other studies, we found a strong predominance of male victims (78%), young age (median age: 4 months) and a high rate of prematurity (22%). Conversely, results on family educational and socioeconomical levels differ from those reported in numerous studies. Parent perpetrators of shaken baby syndrome belong to higher social classes than those of other types of homicide and socially reflect the population they come from. Our study suggests 1) that epidemiological studies on shaken baby syndrome should include both medical and judicial information sources and 2) that primary prevention strategies (especially in maternity wards) should target all social classes.
Monson, Daniel H.; Doak, Daniel F.; Ballachey, Brenda E.; Bodkin, James L.
2011-01-01
Over 20 years ago, the Exxon Valdez oil tanker spilled 42 million L of crude oil into the waters of Prince William Sound, Alaska, USA. At the time of the spill, the sea otter (Enhydra lutris) population inhabiting the spill area suffered substantial acute injuries and loss. Subsequent research has resulted in one of the best-studied species responses to an oil spill in history. However, the question remains: Is the spill still influencing the Prince William Sound sea otter population? Here we fit time-varying population models to data for the sea otter population of western Prince William Sound to quantify the duration and extent of mortality effects from the spill. We hypothesize that the patchy nature of residual oil left in the environment has created a source-sink population dynamic. We fit models using the age distributions of both living and dying animals and estimates of sea otter population size to predict the number of sea otters in the hypothesized sink population and the number lost to this sink due to chronic exposure to residual oil. Our results suggest that the sink population has remained at just over 900 individuals (95% CI: 606-960) between 1990 and 2009, during which time prime-age survival remained 2-6% below pre-spill levels. This reduced survival led to chronic losses of ???900 animals over the past two decades, which is similar in magnitude to the number of sea otter deaths documented in western Prince William Sound during the acute phase of the spill. However, the unaffected source population appears to be counterbalancing these losses, with the model indicating that the sea otter population increased from ???2150 individuals in 1990 to nearly 3000 in 2009. The most optimistic interpretation of our results suggests that mortality effects dissipated between 2005 and 2007. Our results suggest that residual oil can affect wildlife populations on time scales much longer than previously believed and that cumulative chronic effects can be as significant as acute effects. Further, source-sink population dynamics can explain the slow recovery observed in the spill-affected western Prince William Sound sea otter population and are consistent with available data. ??2011 by the Ecological Society of America.
Phenotypic plasticity despite source-sink population dynamics in a long-lived perennial plant.
Anderson, Jill T; Sparks, Jed P; Geber, Monica A
2010-11-01
• Species that exhibit adaptive plasticity alter their phenotypes in response to environmental conditions, thereby maximizing fitness in heterogeneous landscapes. However, under demographic source-sink dynamics, selection should favor traits that enhance fitness in the source habitat at the expense of fitness in the marginal habitat. Consistent with source-sink dynamics, the perennial blueberry, Vaccinium elliottii (Ericaceae), shows substantially higher fitness and population sizes in dry upland forests than in flood-prone bottomland forests, and asymmetrical gene flow occurs from upland populations into bottomland populations. Here, we examined whether this species expresses plasticity to these distinct environments despite source-sink dynamics. • We assessed phenotypic responses to a complex environmental gradient in the field and to water stress in the glasshouse. • Contrary to expectations, V. elliottii exhibited a high degree of plasticity in foliar and root traits (specific leaf area, carbon isotope ratios, foliar nitrogen content, root : shoot ratio, root porosity and root architecture). • We propose that plasticity can be maintained in source-sink systems if it is favored within the source habitat and/or a phylogenetic artifact that is not costly. Additionally, plasticity could be advantageous if habitat-based differences in fitness result from incipient niche expansion. Our results illuminate the importance of evaluating phenotypic traits and fitness components across heterogeneous landscapes. © The Authors (2010). Journal compilation © New Phytologist Trust (2010).
Ship noise extends to frequencies used for echolocation by endangered killer whales.
Veirs, Scott; Veirs, Val; Wood, Jason D
2016-01-01
Combining calibrated hydrophone measurements with vessel location data from the Automatic Identification System, we estimate underwater sound pressure levels for 1,582 unique ships that transited the core critical habitat of the endangered Southern Resident killer whales during 28 months between March, 2011, and October, 2013. Median received spectrum levels of noise from 2,809 isolated transits are elevated relative to median background levels not only at low frequencies (20-30 dB re 1 µPa(2)/Hz from 100 to 1,000 Hz), but also at high frequencies (5-13 dB from 10,000 to 96,000 Hz). Thus, noise received from ships at ranges less than 3 km extends to frequencies used by odontocetes. Broadband received levels (11.5-40,000 Hz) near the shoreline in Haro Strait (WA, USA) for the entire ship population were 110 ± 7 dB re 1 µPa on average. Assuming near-spherical spreading based on a transmission loss experiment we compute mean broadband source levels for the ship population of 173 ± 7 dB re 1 µPa 1 m without accounting for frequency-dependent absorption. Mean ship speed was 7.3 ± 2.0 m/s (14.1 ± 3.9 knots). Most ship classes show a linear relationship between source level and speed with a slope near +2 dB per m/s (+1 dB/knot). Spectrum, 1/12-octave, and 1/3-octave source levels for the whole population have median values that are comparable to previous measurements and models at most frequencies, but for select studies may be relatively low below 200 Hz and high above 20,000 Hz. Median source spectrum levels peak near 50 Hz for all 12 ship classes, have a maximum of 159 dB re 1 µPa(2)/Hz @ 1 m for container ships, and vary between classes. Below 200 Hz, the class-specific median spectrum levels bifurcate with large commercial ships grouping as higher power noise sources. Within all ship classes spectrum levels vary more at low frequencies than at high frequencies, and the degree of variability is almost halved for classes that have smaller speed standard deviations. This is the first study to present source spectra for populations of different ship classes operating in coastal habitats, including at higher frequencies used by killer whales for both communication and echolocation.
Population structure in the Island of Ugljan--demographic processes and marital migration.
Malnar, Ana
2008-12-01
This research on the basic demographic processes and marital migrations of the population on Ugljan Island in the period from 1857 to 2001 was conducted within the context of the long-term anthropological research of the population structure of Croatia's islands. The analysis was based on the study of the origin of 5 244 married couples from Preko, Kali, Kukljica, Lukoran and Ugljan and carried out using data preserved in the old Registers of Marriages. The results show a high level of endogamy and reproductive isolation of the population in all the villages and they also confirm the importance of using historical and demographic sources for researching the shaping of population structures.
Evidence for a Population of High-Redshift Submillimeter Galaxies from Interferometric Imaging
NASA Astrophysics Data System (ADS)
Younger, Joshua D.; Fazio, Giovanni G.; Huang, Jia-Sheng; Yun, Min S.; Wilson, Grant W.; Ashby, Matthew L. N.; Gurwell, Mark A.; Lai, Kamson; Peck, Alison B.; Petitpas, Glen R.; Wilner, David J.; Iono, Daisuke; Kohno, Kotaro; Kawabe, Ryohei; Hughes, David H.; Aretxaga, Itziar; Webb, Tracy; Martínez-Sansigre, Alejo; Kim, Sungeun; Scott, Kimberly S.; Austermann, Jason; Perera, Thushara; Lowenthal, James D.; Schinnerer, Eva; Smolčić, Vernesa
2007-12-01
We have used the Submillimeter Array to image a flux-limited sample of seven submillimeter galaxies, selected by the AzTEC camera on the JCMT at 1.1 mm, in the COSMOS field at 890 μm with ~2" resolution. All of the sources-two radio-bright and five radio-dim-are detected as single point sources at high significance (>6 σ), with positions accurate to ~0.2" that enable counterpart identification at other wavelengths observed with similarly high angular resolution. All seven have IRAC counterparts, but only two have secure counterparts in deep HST ACS imaging. As compared to the two radio-bright sources in the sample, and those in previous studies, the five radio-dim sources in the sample (1) have systematically higher submillimeter-to-radio flux ratios, (2) have lower IRAC 3.6-8.0 μm fluxes, and (3) are not detected at 24 μm. These properties, combined with size constraints at 890 μm (θ<~1.2''), suggest that the radio-dim submillimeter galaxies represent a population of very dusty starbursts, with physical scales similar to local ultraluminous infrared galaxies, with an average redshift higher than radio-bright sources.
Effects of watershed land use on nitrogen concentrations and δ15 nitrogen in groundwater
Cole, Marci L.; Kroeger, Kevin D.; McClelland, J.W.; Valiela, I.
2006-01-01
Eutrophication is a major agent of change affecting freshwater, estuarine, and marine systems. It is largely driven by transportation of nitrogen from natural and anthropogenic sources. Research is needed to quantify this nitrogen delivery and to link the delivery to specific land-derived sources. In this study we measured nitrogen concentrations and δ 15N values in seepage water entering three freshwater ponds and six estuaries on Cape Cod, Massachusetts and assessed how they varied with different types of land use. Nitrate concentrations and δ 15N values in groundwater reflected land use in developed and pristine watersheds. In particular, watersheds with larger populations delivered larger nitrate loads with higher δ 15N values to receiving waters. The enriched δ 15N values confirmed nitrogen loading model results identifying wastewater contributions from septic tanks as the major N source. Furthermore, it was apparent that N coastal sources had a relatively larger impact on the N loads and isotopic signatures than did inland N sources further upstream in the watersheds. This finding suggests that management priorities could focus on coastal sources as a first course of action. This would require management constraints on a much smaller population.
Role of genomics and transcriptomics in selection of reintroduction source populations.
He, Xiaoping; Johansson, Mattias L; Heath, Daniel D
2016-10-01
The use and importance of reintroduction as a conservation tool to return a species to its historical range from which it has been extirpated will increase as climate change and human development accelerate habitat loss and population extinctions. Although the number of reintroduction attempts has increased rapidly over the past 2 decades, the success rate is generally low. As a result of population differences in fitness-related traits and divergent responses to environmental stresses, population performance upon reintroduction is highly variable, and it is generally agreed that selecting an appropriate source population is a critical component of a successful reintroduction. Conservation genomics is an emerging field that addresses long-standing challenges in conservation, and the potential for using novel molecular genetic approaches to inform and improve conservation efforts is high. Because the successful establishment and persistence of reintroduced populations is highly dependent on the functional genetic variation and environmental stress tolerance of the source population, we propose the application of conservation genomics and transcriptomics to guide reintroduction practices. Specifically, we propose using genome-wide functional loci to estimate genetic variation of source populations. This estimate can then be used to predict the potential for adaptation. We also propose using transcriptional profiling to measure the expression response of fitness-related genes to environmental stresses as a proxy for acclimation (tolerance) capacity. Appropriate application of conservation genomics and transcriptomics has the potential to dramatically enhance reintroduction success in a time of rapidly declining biodiversity and accelerating environmental change. © 2016 Society for Conservation Biology.
NASA Astrophysics Data System (ADS)
Djupvik, A. A.; André, Ph.; Bontemps, S.; Motte, F.; Olofsson, G.; Gålfalk, M.; Florén, H.-G.
2006-11-01
Aims.The aim of this paper is to characterise the star formation activity in the poorly studied embedded cluster Serpens/G3-G6, located ~45 arcmin (3 pc) to the south of the Serpens Cloud Core, and to determine the luminosity and mass functions of its population of Young Stellar Objects (YSOs). Methods: .Multi-wavelength broadband photometry was obtained to sample the near and mid-IR spectral energy distributions to separate YSOs from field stars and classify the YSO evolutionary stage. ISOCAM mapping in the two filters LW2 (5-8.5 μm) and LW3 (12-18 μm) of a 19 arcmin × 16 arcmin field was combined with JHKS data from 2MASS, KS data from Arnica/NOT, and L arcmin data from SIRCA/NOT. Continuum emission at 1.3 mm (IRAM) and 3.6 cm (VLA) was mapped to study the cloud structure and the coldest/youngest sources. Deep narrow band imaging at the 2.12 μm S(1) line of H2 from NOTCam/NOT was obtained to search for signs of bipolar outflows. Results: .We have strong evidence for a stellar population of 31 Class II sources, 5 flat-spectrum sources, 5 Class I sources, and two Class 0 sources. Our method does not sample the Class III sources. The cloud is composed of two main dense clumps aligned along a ridge over ~0.5 pc plus a starless core coinciding with absorption features seen in the ISOCAM maps. We find two S-shaped bipolar collimated flows embedded in the NE clump, and propose the two driving sources to be a Class 0 candidate (MMS3) and a double Class I (MMS2). For the Class II population we find a best age of ~2 Myr and compatibility with recent Initial Mass Functions (IMFs) by comparing the observed Class II luminosity function (LF), which is complete to 0.08 L⊙, to various model LFs with different star formation scenarios and input IMFs.
SOURCE APPORTIONMENT STUDIES OF PM-2.5 IN TWO CZECH CITIES: POSSIBLE USES IN HEALTH STUDIES
Aerosol and gas phase air pollutant measurements were made in two cities during an ongoing air pollution-health outcome study in the Czech Republic. Teplice, located in northwestern Bohemia, was selected because the local population was exposed to high air pollution levels. Prac...
Włodarek, Dariusz; Głąbska, Dominika; Kołota, Aleksandra; Adamczyk, Piotr; Czekajło, Aleksandra; Grzeszczak, Władysław; Drozdzowska, Bogna; Pluskiewicz, Wojciech
2014-02-01
The incidence of osteoporosis increases with age and is most frequently observed in postmenopausal women. The objective of the present population-based cohort study was to assess the influence of Ca intake from dairy sources on hip bone mineral density and hip fracture incidence in a group of Polish women over 55 years of age. The main outcome measures included: bone mineral density, the number of previous fractures and the reported Ca intake from dairy sources, assessed by a diet questionnaire. The RAC-OST-POL Study was conducted in the District of Raciborz in the south of Poland. The study was carried out in a group of 625 women, randomly recruited from the general population of women aged >55 years. Median Ca intake from dairy products was lower in the group of women with femoral neck T-score ≤-2·5 than in the group with T-score >-2·5 (275 v. 383 mg/d; P = 0·0019). For total hip score, the difference was close to borderline significance (P = 0·0698). Median Ca intake from dairy products was lower in the group of women with previous fractures than in those without fracture history (336 v. 395 mg/d; P = 0·0254). The main dairy source of Ca in the analysed group included milk drinks, rennet cheese and milk. Higher dairy Ca intake is recommended, since a number of the women analysed were unable to satisfy their Ca requirement exclusively from their diet.
An overview of confounding. Part 2: how to identify it and special situations.
Howards, Penelope P
2018-04-01
Confounding biases study results when the effect of the exposure on the outcome mixes with the effects of other risk and protective factors for the outcome that are present differentially by exposure status. However, not all differences between the exposed and unexposed group cause confounding. Thus, sources of confounding must be identified before they can be addressed. Confounding is absent in an ideal study where all of the population of interest is exposed in one universe and is unexposed in a parallel universe. In an actual study, an observed unexposed population represents the unobserved parallel universe. Thinking about differences between this substitute population and the unexposed parallel universe helps identify sources of confounding. These differences can then be represented in a diagram that shows how risk and protective factors for the outcome are related to the exposure. Sources of confounding identified in the diagram should be addressed analytically and through study design. However, treating all factors that differ by exposure status as confounders without considering the structure of their relation to the exposure can introduce bias. For example, conditions affected by the exposure are not confounders. There are also special types of confounding, such as time-varying confounding and unfixable confounding. It is important to evaluate carefully whether factors of interest contribute to confounding because bias can be introduced both by ignoring potential confounders and by adjusting for factors that are not confounders. The resulting bias can result in misleading conclusions about the effect of the exposure of interest on the outcome. © 2018 Nordic Federation of Societies of Obstetrics and Gynecology.
[Epidemiological methods used in studies in the prevalence of Tourette syndrome].
Stefanoff, Paweł; Mazurek, Jacek
2003-01-01
Tourette syndrome (TS) prevalence was studied since the early 80-ies. Its clinical course is characterised by co-occurrence of motor and vocal tics. Results of previous epidemiological studies were surprisingly divergent: the prevalence varied from 0.5 to 115 cases per 10,000 population. The disease previously recognised as extremely rare and severe is now considered as quite common, with often moderate course. Selected methods used in studies of TS prevalence and analysis of their possible impact on study results are presented. The studies were divided into 3 groups: studies of the hospitalised population, large-scale screenings and studies involving school population, basing on characteristic and size of population, methods of selection of subjects, diagnostic and screening methods used. Studies of the hospitalised population involved patients with most severe symptoms, in different age groups, different methods of final diagnosis confirmation were used. TS prevalence varied from 0.5 up to 15 cases per 10,000 population. Procedures used in large-scale screening studies made possible the elimination of potential selection bias. Large populations were studied using transparent and repetitive confirmation of diagnoses. Their validity was additionally checked in parallel validity studies. TS prevalence was in the range 4.3 to 10 cases per 10,000 population. The highest TS prevalence was obtained in studies involving schoolchildren. Data were gathered from multiple sources: from parents, teachers and children, as well as from classroom observation. Diagnoses were made by experienced clinicians. TS prevalence obtained in school population studies was between 36.2 up to 115 per 10,000 population.
Fontaine, Julie; Dewailly, Éric; Benedetti, Jean-Louis; Pereg, Daria; Ayotte, Pierre; Déry, Serge
2008-01-01
Background Arctic populations are exposed to mercury, lead and cadmium through their traditional diet. Studies have however shown that cadmium exposure is most often attributable to tobacco smoking. The aim of this study is to examine the trends in mercury, lead and cadmium exposure between 1992 and 2004 in the Inuit population of Nunavik (Northern Québec, Canada) using the data obtained from two broad scale health surveys, and to identify sources of exposure in 2004. Methods In 2004, 917 adults aged between 18 and 74 were recruited in the 14 communities of Nunavik to participate to a broad scale health survey. Blood samples were collected and analysed for metals by inductively coupled plasma mass spectrometry, and dietary and life-style characteristics were documented by questionnaires. Results were compared with data obtained in 1992, where 492 people were recruited for a similar survey in the same population. Results Mean blood concentration of mercury was 51.2 nmol/L, which represent a 32% decrease (p < 0.001) between 1992 and 2004. Mercury blood concentrations were mainly explained by age (partial r2 = 0.20; p < 0.0001), and the most important source of exposure to mercury was marine mammal meat consumption (partial r2 = 0.04; p < 0.0001). In 2004, mean blood concentration of lead was 0.19 μmol/L and showed a 55% decrease since 1992. No strong associations were observed with any dietary source, and lead concentrations were mainly explained by age (partial r2 = 0.20.; p < 0.001). Blood cadmium concentrations showed a 22% decrease (p < 0.001) between 1992 and 2004. Once stratified according to tobacco use, means varied between 5.3 nmol/L in never-smokers and 40.4 nmol/L in smokers. Blood cadmium concentrations were mainly associated with tobacco smoking (partial r2 = 0.56; p < 0.0001), while consumption of caribou liver and kidney remain a minor source of cadmium exposure among never-smokers. Conclusion Important decreases in mercury, lead and cadmium exposure were observed. Mercury decrease could be explained by dietary changes and the ban of lead cartridges use likely contributed to the decrease in lead exposure. Blood cadmium concentrations remain high and, underscoring the need for intensive tobacco smoking prevention campaigns in the Nunavik population. PMID:18518986
The modifying effect of the building envelope on population exposure to PM2.5 from outdoor sources.
Taylor, J; Shrubsole, C; Davies, M; Biddulph, P; Das, P; Hamilton, I; Vardoulakis, S; Mavrogianni, A; Jones, B; Oikonomou, E
2014-12-01
A number of studies have estimated population exposure to PM2.5 by examining modeled or measured outdoor PM2.5 levels. However, few have taken into account the mediating effects of building characteristics on the ingress of PM2.5 from outdoor sources and its impact on population exposure in the indoor domestic environment. This study describes how building simulation can be used to determine the indoor concentration of outdoor-sourced pollution for different housing typologies and how the results can be mapped using building stock models and Geographical Information Systems software to demonstrate the modifying effect of dwellings on occupant exposure to PM2.5 across London. Building archetypes broadly representative of those in the Greater London Authority were simulated for pollution infiltration using EnergyPlus. In addition, the influence of occupant behavior on indoor levels of PM2.5 from outdoor sources was examined using a temperature-dependent window-opening scenario. Results demonstrate a range of I/O ratios of PM2.5 , with detached and semi-detached dwellings most vulnerable to high levels of infiltration. When the results are mapped, central London shows lower I/O ratios of PM2.5 compared with outer London, an apparent inversion of exposure most likely caused by the prevalence of flats rather than detached or semi-detached properties. Population exposure to air pollution is typically evaluated using the outdoor concentration of pollutants and does not account for the fact that people in London spend over 80% of their time indoors. In this article, building simulation is used to model the infiltration of outdoor PM2.5 into the domestic indoor environment for dwellings in a London building stock model, and the results mapped. The results show the variation in relative vulnerability of dwellings to pollution infiltration, as well as an estimated absolute indoor concentration across the Greater London Authority (GLA) scaled by local outdoor levels. The practical application of this work is a better understanding of the modifying effect of the building geometry and envelope design on pollution exposure, and how the London building stock may alter exposure. The results will be used to inform population exposure to PM2.5 in future environmental epidemiological studies. © 2014 The Authors. Indoor Air Published by John Wiley & Sons Ltd.
Whitman, Richard L.; Nevers, Meredith B.; Przybyla-Kelly, Katarzyna; Byappanahalli, Muruleedhara N.; Sadowsky, Michael J.; Whitman, Richard L.
2011-01-01
This paper describes the environmental populations of faecal indicator bacteria, and the processes by which these populations become nonpoint sources and influence nearshore water quality. The different possible sources of these indicator bacteria are presented. These include groundwater, springs and seeps, aquatic sediments, beach sand, birds, Cladophora and plant wrack. Also discussed are the environmental factors (moisture, sunlight, temperature and salinity) influencing their survival.
Traits and types of health data repositories.
Wade, Ted D
2014-01-01
We review traits of reusable clinical data and offer a typology of clinical repositories with a range of known examples. Sources of clinical data suitable for research can be classified into types reflecting the data's institutional origin, original purpose, level of integration and governance. Primary data nearly always come from research studies and electronic medical records. Registries collect data on focused populations primarily to track outcomes, often using observational research methods. Warehouses are institutional information utilities repackaging clinical care data. Collections organize data from more organizations than a data warehouse, and more original data sources than a registry. Therefore even if they are heavily curated, their level of internal integration, and thus ease of use, can be less than other types. Federations are like collections except that physical control over data is distributed among donor organizations. Federations sometimes federate, giving a second level of organization. While the size, in number of patients, varies widely within each type of data source, populations over 10 K are relatively numerous, and much larger populations can be seen in warehouses and federations. One imagined ideal structure for research progress has been called an "Information Commons". It would have longitudinal, multi-leveled (environmental through molecular) data on a large population of identified, consenting individuals. These are qualities whose achievement would require long term commitment on the part of many data donors, including a willingness to make their data public.
Coexistence in streams: Do source-sink dynamics allow salamanders to persist with fish predators?
Sepulveda, A.J.; Lowe, W.H.
2011-01-01
Theory suggests that source-sink dynamics can allow coexistence of intraguild predators and prey, but empirical evidence for this coexistence mechanism is limited. We used capture-mark-recapture, genetic methods, and stable isotopes to test whether source-sink dynamics promote coexistence between stream fishes, the intraguild predator, and stream salamanders (Dicamptodon aterrimus), the intraguild prey. Salamander populations from upstream reaches without fish were predicted to maintain or supplement sink populations in downstream reaches with fish. We found instead that downstream reaches with fish were not sinks even though fish consumed salamander larvae-apparent survival, recruitment, and population growth rate did not differ between upstream and downstream reaches. There was also no difference between upstream and downstream reaches in net emigration. We did find that D. aterrimus moved frequently along streams, but believe that this is a response to seasonal habitat changes rather than intraguild predation. Our study provides empirical evidence that local-scale mechanisms are more important than dispersal dynamics to coexistence of streams salamanders and fish. More broadly, it shows the value of empirical data on dispersal and gene flow for distinguishing between local and spatial mechanisms of coexistence. ?? 2011 Springer-Verlag.
Fast radio burst event rate counts - I. Interpreting the observations
NASA Astrophysics Data System (ADS)
Macquart, J.-P.; Ekers, R. D.
2018-02-01
The fluence distribution of the fast radio burst (FRB) population (the `source count' distribution, N (>F) ∝Fα), is a crucial diagnostic of its distance distribution, and hence the progenitor evolutionary history. We critically reanalyse current estimates of the FRB source count distribution. We demonstrate that the Lorimer burst (FRB 010724) is subject to discovery bias, and should be excluded from all statistical studies of the population. We re-examine the evidence for flat, α > -1, source count estimates based on the ratio of single-beam to multiple-beam detections with the Parkes multibeam receiver, and show that current data imply only a very weak constraint of α ≲ -1.3. A maximum-likelihood analysis applied to the portion of the Parkes FRB population detected above the observational completeness fluence of 2 Jy ms yields α = -2.6_{-1.3}^{+0.7 }. Uncertainties in the location of each FRB within the Parkes beam render estimates of the Parkes event rate uncertain in both normalizing survey area and the estimated post-beam-corrected completeness fluence; this uncertainty needs to be accounted for when comparing the event rate against event rates measured at other telescopes.
JAAKKOLA, M S; LAITINEN, S; PIIPARI, R; UITTI, J; NORDMAN, H; HAAPALA, A-M; JAAKKOLA, J J K
2002-01-01
Immunoglobulin G (IgG) antibodies against microbes related to indoor dampness problems have been used as potential biomarkers of fungal exposure in clinical investigations. There is limited information on their relation to asthma. We conducted a population-based incident case–control study to assess the risk of asthma in relation to specific IgG antibodies to eight dampness-related microbes: Aspergillus fumigatus, A. versicolor, Cladosporium cladosporioides, Fusarium oxysporum, Sporobolomyces salmonicolor, Stachybotrys chartarum, Streptomyces albus and Trichoderma citrinoviride. We recruited systematically all new cases of asthma during a 2·5-year study period and randomly selected controls from a source population of adults 21–63 years of age living in the Pirkanmaa Hospital District, South Finland. The clinically diagnosed case series consisted of 521 adults with newly diagnosed asthma and the control series of 932 controls selected randomly from the source population. IgG antibodies were analysed with ELISA. An increased risk of developing asthma in adulthood was significantly related to IgG antibodies to T. citrinoviride, but not to the other moulds. There was no evidence of a dose–response relation between the IgG antibody level and the risk of asthma. T. citrinoviride may play a role in the aetiology of adult-onset asthma or serve as an indicator of other causal factors. PMID:12100029
Ling, Fangqiong; Hwang, Chiachi; LeChevallier, Mark W; Andersen, Gary L; Liu, Wen-Tso
2016-01-01
Drinking water distribution systems (DWDSs) harbor the microorganisms in biofilms and suspended communities, yet the diversity and spatiotemporal distribution have been studied mainly in the suspended communities. This study examined the diversity of biofilms in an urban DWDS, its relationship with suspended communities and its dynamics. The studied DWDS in Urbana, Illinois received conventionally treated and disinfected water sourced from the groundwater. Over a 2-year span, biomass were sampled from household water meters (n=213) and tap water (n=20) to represent biofilm and suspended communities, respectively. A positive correlation between operational taxonomic unit (OTU) abundance and occupancy was observed. Examined under a ‘core-satellite' model, the biofilm community comprised 31 core populations that encompassed 76.7% of total 16 S rRNA gene pyrosequences. The biofilm communities shared with the suspended community highly abundant and prevalent OTUs, which related to methano-/methylotrophs (i.e., Methylophilaceae and Methylococcaceae) and aerobic heterotrophs (Sphingomonadaceae and Comamonadaceae), yet differed by specific core populations and lower diversity and evenness. Multivariate tests indicated seasonality as the main contributor to community structure variation. This pattern was resilient to annual change and correlated to the cyclic fluctuations of core populations. The findings of a distinctive biofilm community assemblage and methano-/methyltrophic primary production provide critical insights for developing more targeted water quality monitoring programs and treatment strategies for groundwater-sourced drinking water systems. PMID:26251872
Ling, Fangqiong; Hwang, Chiachi; LeChevallier, Mark W; Andersen, Gary L; Liu, Wen-Tso
2016-03-01
Drinking water distribution systems (DWDSs) harbor the microorganisms in biofilms and suspended communities, yet the diversity and spatiotemporal distribution have been studied mainly in the suspended communities. This study examined the diversity of biofilms in an urban DWDS, its relationship with suspended communities and its dynamics. The studied DWDS in Urbana, Illinois received conventionally treated and disinfected water sourced from the groundwater. Over a 2-year span, biomass were sampled from household water meters (n=213) and tap water (n=20) to represent biofilm and suspended communities, respectively. A positive correlation between operational taxonomic unit (OTU) abundance and occupancy was observed. Examined under a 'core-satellite' model, the biofilm community comprised 31 core populations that encompassed 76.7% of total 16 S rRNA gene pyrosequences. The biofilm communities shared with the suspended community highly abundant and prevalent OTUs, which related to methano-/methylotrophs (i.e., Methylophilaceae and Methylococcaceae) and aerobic heterotrophs (Sphingomonadaceae and Comamonadaceae), yet differed by specific core populations and lower diversity and evenness. Multivariate tests indicated seasonality as the main contributor to community structure variation. This pattern was resilient to annual change and correlated to the cyclic fluctuations of core populations. The findings of a distinctive biofilm community assemblage and methano-/methyltrophic primary production provide critical insights for developing more targeted water quality monitoring programs and treatment strategies for groundwater-sourced drinking water systems.
ADVANCEMENTS IN SOURCE-TO-DOSE ANALYSIS OF POPULATION EXPOSURES TO OZONE
The current study takes advantage of the observations from regional air quality monitoring networks, the data from the NE-OPS (North East Oxidant and Particulate Study) Project in the Philadelphia region, and regional photochemical air quality model predictions to obtain and co...
Lee, Kathy E.; Blazer, Vicki; Denslow, Nancy D.; Goldstein, Robert M.; Talmage, Philip J.
2000-01-01
The presence of HAAs in selected Minnesota streams was indicated by biological characteristics in common carp. Biological characteristics used in this study identified WWTP effluent as a potential source of HAAs. Additionally, fish located at sites upstream of WWTP effluent primarily draining agricultural land show indications of HAAs, which may be the result of agricultural runoff or other sources of HAAs. There was variability among all sites and among sites within each site group. Differences among sites may be due to differences in water chemistry or fish exposure time. Natural variation in the biological characteristics may account for some of the differences observed in this study. This study and others indicate the presence of HAAs in surface water and the potential signs of endocrine disruption in resident fish populations. Detailed controlled studies could confirm the effects of particular chemicals such as pesticides or components of WWTPs on fish reproduction and population structure.
Recruitment for an efficacy study in chemoprevention--the Concerned Smoker Study.
Arnold, A; Johnstone, B; Stoskopf, B; Skingley, P; Browman, G; Levine, M; Hryniuk, W
1989-09-01
Efficacy studies are important for the development of long-term cancer prevention strategies. Recruitment aims for a highly motivated group of participants. The Concerned Smoker Study is aimed at smokers with at least a 15 pack-year history and bronchial atypia on sputum sampling Recruitment has been primarily through use of the media. During the first year of randomization 905 potential participants expressed interest. Of these, 80 were eventually randomized. With over 60 participants having completed the study only one has defaulted and compliance with the study protocol has been high. Participants became aware of the study through the following sources: daily newspaper 36.6%, weekly newspaper 16.2%, television 14.9%, radio 13.8%, community television 1.3%, other sources 13.3%. Over 90% of potential participants who initially express interest in such a chemoprevention project may not ultimately be suitable. The population chosen for such studies may not be very representative of the more general population; however, a high degree of compliance can be obtained which will provide valuable information on treatment efficacy.
Liu, Xiaobo
2015-07-01
The U.S. Environmental Protection Agency's (EPA) Motor Vehicle Emission Simulator (MOVES) is required by the EPA to replace Mobile 6 as an official on-road emission model. Incorporated with annual vehicle mile traveled (VMT) by Highways Performance Monitoring System (HPMS) vehicle class, MOVES allocates VMT from HPMS to MOVES source (vehicle) types and calculates emission burden by MOVES source type. However, the calculated running emission burden by MOVES source type may be deviated from the actual emission burden because of MOVES source population, specifically the population fraction by MOVES source type in HPMS vehicle class. The deviation is also the result of the use of the universal set of parameters, i.e., relative mileage accumulation rate (relativeMAR), packaged in MOVES default database. This paper presents a novel approach by adjusting the relativeMAR to eliminate the impact of MOVES source population on running exhaust emission and to keep start and evaporative emissions unchanged for both MOVES2010b and MOVES2014. Results from MOVES runs using this approach indicated significant improvements on VMT distribution and emission burden estimation for each MOVES source type. The deviation of VMT by MOVES source type is minimized by using this approach from 12% to less than 0.05% for MOVES2010b and from 50% to less than 0.2% for MOVES2014 except for MOVES source type 53. Source type 53 still remains about 30% variation. The improvement of VMT distribution results in the elimination of emission burden deviation for each MOVES source type. For MOVES2010b, the deviation of emission burdens decreases from -12% for particulate matter less than 2.5 μm (PM2.5) and -9% for carbon monoxide (CO) to less than 0.002%. For MOVES2014, it drops from 80% for CO and 97% for PM2.5 to 0.006%. This approach is developed to more accurately estimate the total emission burdens using EPA's MOVES, both MOVES2010b and MOVES2014, by redistributing vehicle mile traveled (VMT) by Highways Performance Monitoring System (HPMS) class to MOVES source type on the basis of comprehensive traffic study, local link-by-link VMT broken down into MOVES source type.
NPTFit: A Code Package for Non-Poissonian Template Fitting
NASA Astrophysics Data System (ADS)
Mishra-Sharma, Siddharth; Rodd, Nicholas L.; Safdi, Benjamin R.
2017-06-01
We present NPTFit, an open-source code package, written in Python and Cython, for performing non-Poissonian template fits (NPTFs). The NPTF is a recently developed statistical procedure for characterizing the contribution of unresolved point sources (PSs) to astrophysical data sets. The NPTF was first applied to Fermi gamma-ray data to provide evidence that the excess of ˜GeV gamma-rays observed in the inner regions of the Milky Way likely arises from a population of sub-threshold point sources, and the NPTF has since found additional applications studying sub-threshold extragalactic sources at high Galactic latitudes. The NPTF generalizes traditional astrophysical template fits to allow for the ability to search for populations of unresolved PSs that may follow a given spatial distribution. NPTFit builds upon the framework of the fluctuation analyses developed in X-ray astronomy, thus it likely has applications beyond those demonstrated with gamma-ray data. The NPTFit package utilizes novel computational methods to perform the NPTF efficiently. The code is available at http://github.com/bsafdi/NPTFit and up-to-date and extensive documentation may be found at http://nptfit.readthedocs.io.
ERIC Educational Resources Information Center
Delaware Univ., Newark. Coll. of Education.
The question of future sources of food is posed with increasing frequency as the amount of arable land per person decreases with population growth. The role of the ocean as a food supplier is currently being explored. This learning experience is designed for secondary school students. It is divided into four major areas: (1) an overview, (2)…
Hixson, Mark; Mahmud, Abdullah; Hu, Jianlin; Kleeman, Michael J
2012-05-01
The effectiveness of emissions control programs designed to reduce concentrations of airborne particulate matter with an aerodynamic diameter < 2.5 microm (PM2.5) in California's San Joaquin Valley was studied in the year 2030 under three growth scenarios: low, medium, and high population density. Base-case inventories for each choice of population density were created using a coupled emissions modeling system that simultaneously considered interactions between land use and transportation, area source, and point source emissions. The ambient PM2.5 response to each combination of population density and emissions control was evaluated using a regional chemical transport model over a 3-week winter stagnation episode. Comparisons between scenarios were based on regional average and population-weighted PM2.5 concentrations. In the absence of any emissions control program, population-weighted concentrations of PM2.5 in the future San Joaquin Valley are lowest undergrowth scenarios that emphasize low population density. A complete ban on wood burning and a 90% reduction in emissions from food cooking operations and diesel engines must occur before medium- to high-density growth scenarios result in lower population-weighted concentrations of PM2.5. These trends partly reflect the fact that existing downtown urban cores that naturally act as anchor points for new high-density growth in the San Joaquin Valley are located close to major transportation corridors for goods movement. Adding growth buffers around transportation corridors had little impact in the current analysis, since the 8-km resolution of the chemical transport model already provided an artificial buffer around major emissions sources. Assuming that future emissions controls will greatly reduce or eliminate emissions from residential wood burning, food cooking, and diesel engines, the 2030 growth scenario using "as-planned" (medium) population density achieves the lowest population-weighted average PM2.5 concentration in the future San Joaquin Valley during a severe winter stagnation event. The San Joaquin Valley is one of the most heavily polluted air basins in the United States that are projected to experience strong population growth in the coming decades. The best plan to improve air quality in the region combines medium- or high-density population growth with rigorous emissions controls. In the absences of controls, high-density growth leads to increased population exposure to PM2.5 compared with low-density growth scenarios (urban sprawl).
Feeding ducks, bacterial chemotaxis, and the Gini index
NASA Astrophysics Data System (ADS)
Peaudecerf, François J.; Goldstein, Raymond E.
2015-08-01
Classic experiments on the distribution of ducks around separated food sources found consistency with the "ideal free" distribution in which the local population is proportional to the local supply rate. Motivated by this experiment and others, we examine the analogous problem in the microbial world: the distribution of chemotactic bacteria around multiple nearby food sources. In contrast to the optimization of uptake rate that may hold at the level of a single cell in a spatially varying nutrient field, nutrient consumption by a population of chemotactic cells will modify the nutrient field, and the uptake rate will generally vary throughout the population. Through a simple model we study the distribution of resource uptake in the presence of chemotaxis, consumption, and diffusion of both bacteria and nutrients. Borrowing from the field of theoretical economics, we explore how the Gini index can be used as a means to quantify the inequalities of uptake. The redistributive effect of chemotaxis can lead to a phenomenon we term "chemotactic levelling," and the influence of these results on population fitness are briefly considered.
Detecting black bear source-sink dynamics using individual-based genetic graphs.
Draheim, Hope M; Moore, Jennifer A; Etter, Dwayne; Winterstein, Scott R; Scribner, Kim T
2016-07-27
Source-sink dynamics affects population connectivity, spatial genetic structure and population viability for many species. We introduce a novel approach that uses individual-based genetic graphs to identify source-sink areas within a continuously distributed population of black bears (Ursus americanus) in the northern lower peninsula (NLP) of Michigan, USA. Black bear harvest samples (n = 569, from 2002, 2006 and 2010) were genotyped at 12 microsatellite loci and locations were compared across years to identify areas of consistent occupancy over time. We compared graph metrics estimated for a genetic model with metrics from 10 ecological models to identify ecological factors that were associated with sources and sinks. We identified 62 source nodes, 16 of which represent important source areas (net flux > 0.7) and 79 sink nodes. Source strength was significantly correlated with bear local harvest density (a proxy for bear density) and habitat suitability. Additionally, resampling simulations showed our approach is robust to potential sampling bias from uneven sample dispersion. Findings demonstrate black bears in the NLP exhibit asymmetric gene flow, and individual-based genetic graphs can characterize source-sink dynamics in continuously distributed species in the absence of discrete habitat patches. Our findings warrant consideration of undetected source-sink dynamics and their implications on harvest management of game species. © 2016 The Author(s).
Hufford, Kristina M; Krauss, Siegfried L; Veneklaas, Erik J
2012-01-01
The benefits of composite rather than local seed provenances for ecological restoration have recently been argued, largely on the basis of maximizing evolutionary potential. However, these arguments have downplayed the potentially negative consequences of outbreeding depression once mixed provenances interbreed. In this study, we compared intraspecific F1 hybrid performance and molecular marker differentiation among four populations of Stylidium hispidum, a species endemic to Southwestern Australia. Multivariate ordination of 134 AFLP markers analyzed genetic structure and detected two clusters of paired sites that diverged significantly for marker variation along a latitudinal boundary. To test for outbreeding depression and to determine the consequences of molecular population divergence for hybrid fitness, we conducted controlled pollinations and studied germination and survival for three cross categories (within-population crosses, short- and long-distance F1 hybrids) for paired sites distributed within and between the two genetically differentiated regions. We found evidence of outbreeding depression in long-distance hybrids (111–124 km), and inbreeding depression among progeny of within-population crosses, relative to short-distance (3–10 km) hybrids, suggesting an intermediate optimal outcrossing distance in this species. These results are discussed in light of the evolutionary consequences of mixing seed sources for biodiversity restoration. PMID:23139884
Labarrière, Nathalie; Gervois, Nadine; Bonnin, Annabelle; Bouquié, Régis; Jotereau, Francine; Lang, François
2008-02-01
Choosing a reliable source of tumor-specific T lymphocytes and an efficient method to isolate these cells still remains a critical issue in adoptive cellular therapy (ACT). In this study, we assessed the capacity of MHC/peptide based immunomagnetic sorting followed by polyclonal T cell expansion to derive pure polyclonal and tumor-reactive Melan-A specific T cell populations from melanoma patient's PBMC and TIL. We first demonstrated that this approach was extremely efficient and reproducible. We then used this procedure to compare PBMC and TIL-derived cells from three melanoma patients in terms of avidity for Melan-A A27L analog, Melan-A(26-35)and Melan-A(27-35), tumor reactivity (lysis and cytokine production) and repertoire. Regardless of their origin, i.e., fresh PBMC, peptide stimulated PBMC or TIL, all sorted populations (from the three patients) were cytotoxic against HLA-A2+ melanoma cell lines expressing Melan-A. Although some variability in peptide avidity, lytic activity and cytokine production was observed between populations of different origins in a given patient, it differed from one patient to another and thus no correlation could be drawn between T cell source and reactivity. Analysis of Vbeta usage within the sorted populations showed the recurrence of Vbeta3 and Vbeta14 subfamilies in the three patients but differences in the rest of the Melan-A repertoire. In addition, in two patients, we observed major repertoire differences between populations sorted from the three sources. We especially documented that in vitro peptide stimulation of PBMC, used to facilitate the sort by enriching in specific T lymphocytes, could significantly alter their repertoire and reactivity towards tumor cells. We conclude that PBMC which are easily obtained from all melanoma patients, can be as good a source as TIL to derive high amounts of tumor-reactive Melan-A specific T cells, with this selection/amplification procedure. However, the conditions of peptide stimulation should be improved to prevent a possible loss of reactive clonotypes.
The cost of vision loss in Canada. 1. Methodology.
Gordon, Keith D; Cruess, Alan F; Bellan, Lorne; Mitchell, Scott; Pezzullo, M Lynne
2011-08-01
This paper outlines the methodology used to estimate the cost of vision loss in Canada. The results of this study will be presented in a second paper. The cost of vision loss (VL) in Canada was estimated using a prevalence-based approach. This was done by estimating the number of people with VL in a base period (2007) and the costs associated with treating them. The cost estimates included direct health system expenditures on eye conditions that cause VL, as well as other indirect financial costs such as productivity losses. Estimates were also made of the value of the loss of healthy life, measured in Disability Adjusted Life Years or DALY's. To estimate the number of cases of VL in the population, epidemiological data on prevalence rates were applied to population data. The number of cases of VL was stratified by gender, age, ethnicity, severity and cause. The following sources were used for estimating prevalence: Population-based eye studies; Canadian Surveys; Canadian journal articles and research studies; and International Population Based Eye Studies. Direct health costs were obtained primarily from Health Canada and Canadian Institute for Health Information (CIHI) sources, while costs associated with productivity losses were based on employment information compiled by Statistics Canada and on economic theory of productivity loss. Costs related to vision rehabilitation (VR) were obtained from Canadian VR organizations. This study shows that it is possible to estimate the costs for VL for a country in the absence of ongoing local epidemiological studies. Copyright © 2011 Canadian Ophthalmological Society. Published by Elsevier Inc. All rights reserved.
Jennison, Amy V.; Masson, Jesse J.; Fang, Ning-Xia; Graham, Rikki M.; Bradbury, Mark I.; Fegan, Narelle; Gobius, Kari S.; Graham, Trudy M.; Guglielmino, Christine J.; Brown, Janelle L.; Fox, Edward M.
2017-01-01
Listeriosis remains among the most important bacterial illnesses, with a high associated mortality rate. Efforts to control listeriosis require detailed knowledge of the epidemiology of the disease itself, and its etiological bacterium, Listeria monocytogenes. In this study we provide an in-depth analysis of the epidemiology of 224 L. monocytogenes isolates from Australian clinical and non-clinical sources. Non-human sources included meat, dairy, seafood, fruit, and vegetables, along with animal and environmental isolates. Serotyping, Multi-Locus Sequence Typing, and analysis of inlA gene sequence were performed. Serogroups IIA, IIB, and IVB comprised 94% of all isolates, with IVB over-represented among clinical isolates. Serogroup IIA was the most common among dairy and meat isolates. Lineage I isolates were most common among clinical isolates, and 52% of clinical isolates belonged to ST1. Overall 39 STs were identified in this study, with ST1 and ST3 containing the largest numbers of L. monocytogenes isolates. These STs comprised 40% of the total isolates (n = 90), and both harbored isolates from clinical and non-clinical sources. ST204 was the third most common ST. The high prevalence of this group among L. monocytogenes populations has not been reported outside Australia. Twenty-seven percent of the STs in this study contained exclusively clinical isolates. Analysis of the virulence protein InlA among isolates in this study identified a truncated form of the protein among isolates from ST121 and ST325. The ST325 group contained a previously unreported novel mutation leading to production of a 93 amino acid protein. This study provides insights in the population structure of L. monocytogenes isolated in Australia, which will contribute to public health knowledge relating to this important human pathogen. PMID:28428781
MSX Colors of Radio-Selected HII Regions in the Milky Way
NASA Astrophysics Data System (ADS)
Giveon, U.; Becker, R. H.; Helfand, D. J.; White, R. L.
2003-12-01
Investigation of the color-space properties of mid-infrared sources in the MSX Galactic plane catalog reveals two distinct populations - a blue population composed mainly of evolved stars, masers and molecular clouds, and a red population comprising sources of a nebular nature - HII regions, planetary nebulae, and unclassified radio sources. We compare the MSX catalog to 5 GHz VLA maps of the first quadrant of the Galactic plane. A catalog extracted from these maps was published first by Becker et al., but we have re-reduced the data with significantly improved calibration and mosaicing procedures, resulting in an increase of ˜ 60% in the number of detected sources. Comparison of the radio and infrared catalogs resulted in a sample of 491 matches, out of which we estimate 38 to be false counterparts, all of them from the MSX red population. The radio sources with infrared counterparts are found to have extremely small scale height (FWHM of 14' or ˜ 35 pc), and have thermal radio spectrum. These properties suggest that the sample is dominated by HII regions, most of them are previously uncataloged. This research is supported be the National Science Foundation.
Microlensing of an extended source by a power-law mass distribution
NASA Astrophysics Data System (ADS)
Congdon, Arthur B.; Keeton, Charles R.; Osmer, S. J.
2007-03-01
Microlensing promises to be a powerful tool for studying distant galaxies and quasars. As the data and models improve, there are systematic effects that need to be explored. Quasar continuum and broad-line regions may respond differently to microlensing due to their different sizes; to understand this effect, we study microlensing of finite sources by a mass function of stars. We find that microlensing is insensitive to the slope of the mass function but does depend on the mass range. For negative-parity images, diluting the stellar population with dark matter increases the magnification dispersion for small sources and decreases it for large sources. This implies that the quasar continuum and broad-line regions may experience very different microlensing in negative-parity lensed images. We confirm earlier conclusions that the surface brightness profile and geometry of the source have little effect on microlensing. Finally, we consider non-circular sources. We show that elliptical sources that are aligned with the direction of shear have larger magnification dispersions than sources with perpendicular alignment, an effect that becomes more prominent as the ellipticity increases. Elongated sources can lead to more rapid variability than circular sources, which raises the prospect of using microlensing to probe source shape.
Alu polymorphic insertions reveal genetic structure of north Indian populations.
Tripathi, Manorama; Tripathi, Piyush; Chauhan, Ugam Kumari; Herrera, Rene J; Agrawal, Suraksha
2008-10-01
The Indian subcontinent is characterized by the ancestral and cultural diversity of its people. Genetic input from several unique source populations and from the unique social architecture provided by the caste system has shaped the current genetic landscape of India. In the present study 200 individuals each from three upper-caste and four middle-caste Hindu groups and from two Muslim populations in North India were examined for 10 polymorphic Alu insertions (PAIs). The investigated PAIs exhibit high levels of polymorphism and average heterozygosity. Limited interpopulation variance and genetic flow in the present study suggest admixture. The results of this study demonstrate that, contrary to common belief, the caste system has not provided an impermeable barrier to genetic exchange among Indian groups.
Costa, M C; Helweg-Larsen, J; Lundgren, Bettina; Antunes, F; Matos, O
2003-11-01
The aim of this study was to evaluate the frequency of mutations of the P. jiroveci dihydropteroate synthase (DHPS) gene in an immunocompromised Portuguese population and to investigate the possible association between DHPS mutations and sulpha exposure. In the studied population, DHPS gene mutations were not significantly more frequent in patients exposed to sulpha drugs compared with patients not exposed (P=0.390). The results of this study suggest that DHPS gene mutations are frequent in the Portuguese immunocompromised population but do not seem associated with previous sulpha exposure. These results are consistent with the possibility of an incidental acquisition and transmission of P. jiroveci mutant types, either by person to person transmission or from an environmental source.
Chandra Detection of an Evolved Population of Young Stars in Serpens South
NASA Astrophysics Data System (ADS)
Winston, E.; Wolk, S. J.; Gutermuth, R.; Bourke, T. L.
2018-06-01
We present a Chandra study of the deeply embedded Serpens South star-forming region, examining cluster structure and disk properties at the earliest stages. In total, 152 X-ray sources are detected. Combined with Spitzer and 2MASS photometry, 66 X-ray sources are reliably matched to an IR counterpart. We identify 21 class I, 6 flat spectrum, 16 class II, and 18 class III young stars; 5 were unclassified. Eighteen sources were variable in X-rays, 8 exhibiting flare-like emission and one source being periodic. The cluster’s X-ray luminosity distance was estimated: the best match was to the nearer distance of 260 pc for the front of the Aquila Rift complex. The ratio of N H to A K is found to be ∼0.68 × 1022, similar to that measured in other young low-mass regions, but lower than that measured in the interstellar medium and high-mass clusters (∼(1.6–2) × 1022). We find that the spatial distribution closely follows that of the dense filament from which the stars have formed, with the class II population still strongly associated with the filament. There are four subclusters in the field, with three forming knots in the filament, and a fourth to the west, which may not be associated but may be contributing to the distributed class III population. A high percentage of diskless class IIIs (upper limit 30% of classified X-ray sources) in such a young cluster could indicate that processing of disks is influenced by the cluster environment and is not solely dependent on timescale.
Capello, Katia; Bortolotti, Laura; Lanari, Manuela; Baioni, Elisa; Mutinelli, Franco; Vascellari, Marta
2015-01-01
The knowledge of the size and demographic structure of animal populations is a necessary prerequisite for any population-based epidemiological study, especially to ascertain and interpret prevalence data, to implement surveillance plans in controlling zoonotic diseases and, moreover, to provide accurate estimates of tumours incidence data obtained by population-based registries. The main purpose of this study was to provide an accurate estimate of the size and structure of the canine population in Veneto region (north-eastern Italy), using the Lincoln-Petersen version of the capture-recapture methodology. The Regional Canine Demographic Registry (BAC) and a sample survey of households of Veneto Region were the capture and recapture sources, respectively. The secondary purpose was to estimate the size and structure of the feline population in the same region, using the same survey applied for dog population. A sample of 2465 randomly selected households was drawn and submitted to a questionnaire using the CATI technique, in order to obtain information about the ownership of dogs and cats. If the dog was declared to be identified, owner's information was used to recapture the dog in the BAC. The study was conducted in Veneto Region during 2011, when the dog population recorded in the BAC was 605,537. Overall, 616 households declared to possess at least one dog (25%), with a total of 805 dogs and an average per household of 1.3. The capture-recapture analysis showed that 574 dogs (71.3%, 95% CI: 68.04-74.40%) had been recaptured in both sources, providing a dog population estimate of 849,229 (95% CI: 814,747-889,394), 40% higher than that registered in the BAC. Concerning cats, 455 of 2465 (18%, 95% CI: 17-20%) households declared to possess at least one cat at the time of the telephone interview, with a total of 816 cats. The mean number of cats per household was equal to 1.8, providing an estimate of the cat population in Veneto region equal to 663,433 (95% CI: 626,585-737,159). The estimate of the size and structure of owned canine and feline populations in Veneto region provide useful data to perform epidemiological studies and monitoring plans in this area. Copyright © 2014 Elsevier B.V. All rights reserved.
Tarrés, Josep; Albertí, Constança; Martínez-Artés, Xavier; Abós-Herràndiz, Rafael; Rosell-Murphy, Magdalena; García-Allas, Isabel; Krier, Ilona; Cantarell, Gloria; Gallego, Miguel; Canela-Soler, Jaume; Orriols, Ramon
2013-08-01
Few studies have focused on pleural mesothelioma and environmental exposure in individuals residing around an industrial source of asbestos. The aim of this study is to determine whether residential distance and wind conditions are related to the risk of developing pleural mesothelioma. In this retrospective cohort study carried out in an area of Barcelona province (Catalonia, Spain), 24 environmental pleural mesothelioma cases were diagnosed between 2000 and 2009. We calculated the age-standardised incidence rate ratios of developing this disease in the population studied, taking into account the residential distance from the plant. For cases living within a 500-m radius of the plant, the geographical location in relation to the factory was also assessed. The incidence rate of environmental pleural mesothelioma was higher in the population living within 500 m of the plant than in those living in a radius of 500-2000 m and much higher than those living at 2000-10 000 m. The highest incidence rate ratio for pleural mesothelioma (161.9) was found in the southeast quadrant of the 500-m area, coinciding with the predominant wind direction. Residential distance from an industrial source of asbestos and local wind conditions have a considerable impact on the risk of developing environmental pleural mesothelioma.
Fontanilla, Ian Kendrich C; Sta Maria, Inna Mikaella P; Garcia, James Rainier M; Ghate, Hemant; Naggs, Fred; Wade, Christopher M
2014-01-01
The Giant African Land Snail, Achatina ( = Lissachatina) fulica Bowdich, 1822, is a tropical crop pest species with a widespread distribution across East Africa, the Indian subcontinent, Southeast Asia, the Pacific, the Caribbean, and North and South America. Its current distribution is attributed primarily to the introduction of the snail to new areas by Man within the last 200 years. This study determined the extent of genetic diversity in global A. fulica populations using the mitochondrial 16S ribosomal RNA gene. A total of 560 individuals were evaluated from 39 global populations obtained from 26 territories. Results reveal 18 distinct A. fulica haplotypes; 14 are found in East Africa and the Indian Ocean islands, but only two haplotypes from the Indian Ocean islands emerged from this region, the C haplotype, now distributed across the tropics, and the D haplotype in Ecuador and Bolivia. Haplotype E from the Philippines, F from New Caledonia and Barbados, O from India and Q from Ecuador are variants of the emergent C haplotype. For the non-native populations, the lack of genetic variation points to founder effects due to the lack of multiple introductions from the native range. Our current data could only point with certainty to the Indian Ocean islands as the earliest known common source of A. fulica across the globe, which necessitates further sampling in East Africa to determine the source populations of the emergent haplotypes.
Fontanilla, Ian Kendrich C.; Sta. Maria, Inna Mikaella P.; Garcia, James Rainier M.; Ghate, Hemant; Naggs, Fred; Wade, Christopher M.
2014-01-01
The Giant African Land Snail, Achatina ( = Lissachatina) fulica Bowdich, 1822, is a tropical crop pest species with a widespread distribution across East Africa, the Indian subcontinent, Southeast Asia, the Pacific, the Caribbean, and North and South America. Its current distribution is attributed primarily to the introduction of the snail to new areas by Man within the last 200 years. This study determined the extent of genetic diversity in global A. fulica populations using the mitochondrial 16S ribosomal RNA gene. A total of 560 individuals were evaluated from 39 global populations obtained from 26 territories. Results reveal 18 distinct A. fulica haplotypes; 14 are found in East Africa and the Indian Ocean islands, but only two haplotypes from the Indian Ocean islands emerged from this region, the C haplotype, now distributed across the tropics, and the D haplotype in Ecuador and Bolivia. Haplotype E from the Philippines, F from New Caledonia and Barbados, O from India and Q from Ecuador are variants of the emergent C haplotype. For the non-native populations, the lack of genetic variation points to founder effects due to the lack of multiple introductions from the native range. Our current data could only point with certainty to the Indian Ocean islands as the earliest known common source of A. fulica across the globe, which necessitates further sampling in East Africa to determine the source populations of the emergent haplotypes. PMID:25203830
On the Spatially Resolved Star Formation History in M51. II. X-Ray Binary Population Evolution
NASA Astrophysics Data System (ADS)
Lehmer, B. D.; Eufrasio, R. T.; Markwardt, L.; Zezas, A.; Basu-Zych, A.; Fragos, T.; Hornschemeier, A. E.; Ptak, A.; Tzanavaris, P.; Yukita, M.
2017-12-01
We present a new technique for empirically calibrating how the X-ray luminosity function (XLF) of X-ray binary (XRB) populations evolves following a star formation event. We first utilize detailed stellar population synthesis modeling of far-UV-to-far-IR photometry of the nearby face-on spiral galaxy M51 to construct maps of the star formation histories (SFHs) on subgalactic (≈400 pc) scales. Next, we use the ≈850 ks cumulative Chandra exposure of M51 to identify and isolate 2-7 keV detected point sources within the galaxy, and we use our SFH maps to recover the local properties of the stellar populations in which each X-ray source is located. We then divide the galaxy into various subregions based on their SFH properties (e.g., star formation rate (SFR) per stellar mass ({M}\\star ) and mass-weighted stellar age) and group the X-ray point sources according to the characteristics of the regions in which they are found. Finally, we construct and fit a parameterized XLF model that quantifies how the XLF shape and normalization evolves as a function of the XRB population age Our best-fit model indicates that the XRB XLF per unit stellar mass declines in normalization, by ˜3-3.5 dex, and steepens in slope from ≈10 Myr to ≈10 Gyr. We find that our technique recovers results from past studies of how XRB XLFs and XRB luminosity scaling relations vary with age and provides a self-consistent picture for how XRB XLFs evolve with age.
Kim, Eunji; Shin, Seung Gu; Jannat, Md Abu Hanifa; Tongco, Jovale Vincent; Hwang, Seokhwan
2017-12-01
Using organic wastes as an alternative to commercial carbon sources could be beneficial by reducing costs and environmental impacts. In this study, food waste-recycling wastewater (FRW) was evaluated as an alternative carbon source for biological denitrification over a period of seven months in a full-scale sewage wastewater treatment plant. The denitrification performance was stable with a mean nitrate removal efficiency of 97.2%. Propionate was initially the most persistent volatile fatty acid, but was completely utilized after 19days. Eubacteriacea, Saprospiraceae, Rhodocyclaceae and Comamonadaceae were the major bacterial families during FRW treatment and were regarded as responsible for hydrolysis (former two) and nitrate removal (latter two) of FRW. These results demonstrate that FRW can be an effective external carbon source; process stabilization was linked to the acclimation and function of bacterial populations to the change of carbon source. Copyright © 2017 Elsevier Ltd. All rights reserved.
Biomonitoring studies provide valuable information on exposures to chemical contaminants, including pesticides. They can help to identify highly exposed populations and may be used to develop hypotheses about sources and pathways for exposure. A biomonitoring study was conducte...
Herschel Key Program Heritage: a Far-Infrared Source Catalog for the Magellanic Clouds
NASA Astrophysics Data System (ADS)
Seale, Jonathan P.; Meixner, Margaret; Sewiło, Marta; Babler, Brian; Engelbracht, Charles W.; Gordon, Karl; Hony, Sacha; Misselt, Karl; Montiel, Edward; Okumura, Koryo; Panuzzo, Pasquale; Roman-Duval, Julia; Sauvage, Marc; Boyer, Martha L.; Chen, C.-H. Rosie; Indebetouw, Remy; Matsuura, Mikako; Oliveira, Joana M.; Srinivasan, Sundar; van Loon, Jacco Th.; Whitney, Barbara; Woods, Paul M.
2014-12-01
Observations from the HERschel Inventory of the Agents of Galaxy Evolution (HERITAGE) have been used to identify dusty populations of sources in the Large and Small Magellanic Clouds (LMC and SMC). We conducted the study using the HERITAGE catalogs of point sources available from the Herschel Science Center from both the Photodetector Array Camera and Spectrometer (PACS; 100 and 160 μm) and Spectral and Photometric Imaging Receiver (SPIRE; 250, 350, and 500 μm) cameras. These catalogs are matched to each other to create a Herschel band-merged catalog and then further matched to archival Spitzer IRAC and MIPS catalogs from the Spitzer Surveying the Agents of Galaxy Evolution (SAGE) and SAGE-SMC surveys to create single mid- to far-infrared (far-IR) point source catalogs that span the wavelength range from 3.6 to 500 μm. There are 35,322 unique sources in the LMC and 7503 in the SMC. To be bright in the FIR, a source must be very dusty, and so the sources in the HERITAGE catalogs represent the dustiest populations of sources. The brightest HERITAGE sources are dominated by young stellar objects (YSOs), and the dimmest by background galaxies. We identify the sources most likely to be background galaxies by first considering their morphology (distant galaxies are point-like at the resolution of Herschel) and then comparing the flux distribution to that of the Herschel Astrophysical Terahertz Large Area Survey (ATLAS) survey of galaxies. We find a total of 9745 background galaxy candidates in the LMC HERITAGE images and 5111 in the SMC images, in agreement with the number predicted by extrapolating from the ATLAS flux distribution. The majority of the Magellanic Cloud-residing sources are either very young, embedded forming stars or dusty clumps of the interstellar medium. Using the presence of 24 μm emission as a tracer of star formation, we identify 3518 YSO candidates in the LMC and 663 in the SMC. There are far fewer far-IR bright YSOs in the SMC than the LMC due to both the SMC's smaller size and its lower dust content. The YSO candidate lists may be contaminated at low flux levels by background galaxies, and so we differentiate between sources with a high (“probable”) and moderate (“possible”) likelihood of being a YSO. There are 2493/425 probable YSO candidates in the LMC/SMC. Approximately 73% of the Herschel YSO candidates are newly identified in the LMC, and 35% in the SMC. We further identify a small population of dusty objects in the late stages of stellar evolution including extreme and post-asymptotic giant branch, planetary nebulae, and supernova remnants. These populations are identified by matching the HERITAGE catalogs to lists of previously identified objects in the literature. Approximately half of the LMC sources and one quarter of the SMC sources are too faint to obtain accurate ample FIR photometry and are unclassified.
NASA Astrophysics Data System (ADS)
Gilliam, Melissa; Jagoda, Patrick; Fabiyi, Camille; Lyman, Phoebe; Wilson, Claire; Hill, Brandon; Bouris, Alida
2017-06-01
This project developed and studied The Source, an alternate reality game (ARG) designed to foster interest and knowledge related to science, technology, engineering, and math (STEM) among youth from populations underrepresented in STEM fields. ARGs are multiplayer games that engage participants across several media such as shared websites, social media, personal communications, and real-world settings to complete activities and collaborate with team members. The Source was a five-week summer program with 144 participants from Chicago aged 13 to 18 years. The Source incorporated six socio-contextual factors derived from three frameworks: Chang's (ERIC Digest, 2002) recommendations for engaging underrepresented populations in STEM careers, Lave and Wenger's (Cambridge University Press, 1991) situated learning model, and Barron's (Human Development, 49(4); 193-224, 2006) learning ecology perspective. These factors aligned with the program's aims of promoting (1) social community and peer support, (2) collaboration and teamwork, (3) real-world relevance and investigative learning, (4) mentoring and exposure to STEM professionals, (5) hands-on activities to foster transferable skill building, and (6) interface with technology. This paper presents results from 10 focus groups and 10 individual interviews conducted with a subset of the 144 youth participants who completed the game. It describes how these six factors were realized through The Source and uses them as a lens for considering how The Source functioned pedagogically. Qualitative findings describe youth's perception of The Source's potential influence on STEM interest, engagement, and identity formation. Despite limitations, study results indicate that underrepresented youth can engage in an immersive, narrative, and game-based experience as a potential mechanism for piquing and developing STEM interest and skills, particularly among underrepresented youth.
Rudolph, Abby E.; Crawford, Natalie D.; Ompad, Danielle C.; Benjamin, Ebele O.; Stern, Rachel J.; Fuller, Crystal M.
2011-01-01
Objective In New York, syringe exchange programs (SEPs) and pharmacies provide syringe access for IDUs but may be unable to meet the needs of all IDUs. This analysis aims to describe IDUs who access syringes through different outlets to help inform the prevention needs of IDUs who under-utilize safe syringe sources in a city where syringe availability is high relative to other U.S. cities. Design Cross-sectional study Setting New York City (2005–2007) Participants 285 IDUs recruited using street-intercept sampling Intervention(s) Not Applicable Main outcome measure(s) IDUs using SEPs, pharmacies, or other outlets as a primary syringe source were compared by sociodemographic characteristics, injection practices and medical service utilization. Results Chi-square tests and polytomous logistic regression were used to compare IDUs with different self-reported primary syringe sources used 6 months prior to study entry. Compared with IDUs using other syringe sources, those using primarily SEPs were less likely to be Black (AOR:0.26 95%CI:0.11–0.57), more likely to inject daily (AOR:3.32; 95%CI:1.58–6.98), and more likely to inject with a new syringe (AOR:2.68; 95%CI:1.30–5.54). Compared with IDUs using other syringe sources, those using primarily pharmacies were less likely to be Black (AOR:0.39; 95%CI0.17–0.90). Conclusion These data suggest that pharmacies and SEPs may be reaching different populations of IDUs and highlight a sub-population of highly marginalized IDUs (Black and infrequent injectors) who are under-utilizing safe syringe sources in New York City. Targeted interventions are needed to reduce racial disparities and increase utilization of safe syringe outlets. PMID:20199954
Assessing genome-wide copy number variation in the Han Chinese population.
Lu, Jianqi; Lou, Haiyi; Fu, Ruiqing; Lu, Dongsheng; Zhang, Feng; Wu, Zhendong; Zhang, Xi; Li, Changhua; Fang, Baijun; Pu, Fangfang; Wei, Jingning; Wei, Qian; Zhang, Chao; Wang, Xiaoji; Lu, Yan; Yan, Shi; Yang, Yajun; Jin, Li; Xu, Shuhua
2017-10-01
Copy number variation (CNV) is a valuable source of genetic diversity in the human genome and a well-recognised cause of various genetic diseases. However, CNVs have been considerably under-represented in population-based studies, particularly the Han Chinese which is the largest ethnic group in the world. To build a representative CNV map for the Han Chinese population. We conducted a genome-wide CNV study involving 451 male Han Chinese samples from 11 geographical regions encompassing 28 dialect groups, representing a less-biased panel compared with the currently available data. We detected CNVs by using 4.2M NimbleGen comparative genomic hybridisation array and whole-genome deep sequencing of 51 samples to optimise the filtering conditions in CNV discovery. A comprehensive Han Chinese CNV map was built based on a set of high-quality variants (positive predictive value >0.8, with sizes ranging from 369 bp to 4.16 Mb and a median of 5907 bp). The map consists of 4012 CNV regions (CNVRs), and more than half are novel to the 30 East Asian CNV Project and the 1000 Genomes Project Phase 3. We further identified 81 CNVRs specific to regional groups, which was indicative of the subpopulation structure within the Han Chinese population. Our data are complementary to public data sources, and the CNV map may facilitate in the identification of pathogenic CNVs and further biomedical research studies involving the Han Chinese population. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2017. All rights reserved. No commercial use is permitted unless otherwise expressly granted.
Benítez-Malvido, Julieta; González-Di Pierro, Ana Ma; Lombera, Rafael; Guillén, Susana; Estrada, Alejandro
2014-06-01
• Premise of the study: Frugivore selection of fruits and treatment of seeds together with seed deposition site are crucial for the population dynamics of vertebrate-dispersed plants. However, frugivore species may influence dispersal quality differently even when feeding on the same fruit species and, while animals disperse some seeds, others simply fall beneath the parent plant.• Methods: In southern Mexico, we investigated to see if within-species seed traits (i.e., length, width, weight, and volume) and germination success differed according to seed source. For five tropical tree species we obtained ingested seeds from two sources, howler monkey (Alouatta pigra) and spider monkey (Ateles geoffroyi) feces; and noningested seeds from two sources, the ground and tree crowns (with predispersed seeds used as control).• Key results: A principal components' analysis showed that traits of seeds ingested by howler monkeys differed from other sources while seeds ingested by spider monkeys were similar to noningested seeds. Howlers consumed on average the larger seeds in Ampelocera hottlei, Brosimum lactescens, and Dialium guianense. Both primate species consumed the smaller seeds in Spondias mombin, while no seed trait differences among seed sources were found in Spondias radlkoferi. For all five tree species, germination rate was greatest for seeds ingested by howler monkeys.• Conclusions: For the studied plant species, seed ingestion by howler monkeys confers higher dispersal quality than ingestion by spider monkeys or nondispersal. Dispersal services of both primate species, however, are not redundant and may contribute to germination heterogeneity within plant populations in tropical forests. © 2014 Botanical Society of America, Inc.
Consolidating Data of Global Urban Populations: a Comparative Approach
NASA Astrophysics Data System (ADS)
Blankespoor, B.; Khan, A.; Selod, H.
2017-12-01
Global data on city populations are essential for the study of urbanization, city growth and the spatial distribution of human settlements. Such data are either gathered by combining official estimates of urban populations from across countries or extracted from gridded population models that combine these estimates with geospatial data. These data sources provide varying estimates of urban populations and each approach has its advantages and limitations. In particular, official figures suffer from a lack of consistency in defining urban units (across both space and time) and often provide data for jurisdictions rather than the functionally meaningful urban area. On the other hand, gridded population models require a user-imposed definition to identify urban areas and are constrained by the modelling techniques and input data employed. To address these drawbacks, we combine these approaches by consolidating information from three established sources: (i) the Citypopulation.de (Brinkhoff, 2016); (ii) the World Urban Prospects data (United Nations, 2014); and (iii) the Global Human Settlements population grid (GHS-POP) (EC - JRC, 2015). We create urban footprints with GHS-POP and spatially merge georeferenced city points from both UN WUP and Citypopulation.de with these urban footprints to identify city points that belong to a single agglomeration. We create a consolidated dataset by combining population data from the UN WUP and Citypopulation.de. The flexible framework outlined can incorporate information from alternative inputs to identify urban clusters e.g. by using night-time lights, built-up area or alternative gridded population models (e.g WorldPop or Landscan) and the parameters employed (e.g. density thresholds for urban footprints) may also be adjusted, e.g., as a function of city-specific characteristics. Our consolidated dataset provides a wider and more accurate coverage of city populations to support studies of urbanization. We apply the data to re-examine Zipf's Law. Brinkhoff, Thomas. 2016. City Population.EC - JRC; Columbia University, CIESIN. 2015. GHS population grid, derived from GPW4, multi-temporal (1975, 1990, 2000, 2015).United Nations, Department of Economic and Social Affairs, Population Division. 2014. World Urbanization Prospects: 2014 Revision.
The use of Facebook for virtual asynchronous focus groups in qualitative research.
Biedermann, Narelle
2018-02-01
The Internet and the development of more user-engaging applications have opened a whole new world for researchers as a means of recruitment and data collection source. This paper describes the methodological approach of a research study that explored the experiences of Australian military spouses who packed up their family and home to accompany their spouse on an overseas posting. The study used Facebook as a recruitment tool and then as a data source through the conduct of an asynchronous virtual focus group. This paper outlines the advantages and disadvantages of this unique data source as a means of capturing the voices of a hard-to-reach population.
Iorio, Alfonso; Keepanasseril, Arun; Foster, Gary; Navarro-Ruan, Tamara; McEneny-King, Alanna; Edginton, Andrea N; Thabane, Lehana
2016-12-15
Individual pharmacokinetic assessment is a critical component of tailored prophylaxis for hemophilia patients. Population pharmacokinetics allows using individual sparse data, thus simplifying individual pharmacokinetic studies. Implementing population pharmacokinetics capacity for the hemophilia community is beyond individual reach and requires a system effort. The Web-Accessible Population Pharmacokinetic Service-Hemophilia (WAPPS-Hemo) project aims to assemble a database of patient pharmacokinetic data for all existing factor concentrates, develop and validate population pharmacokinetics models, and integrate these models within a Web-based calculator for individualized pharmacokinetic estimation in patients at participating treatment centers. Individual pharmacokinetic studies on factor VIII and IX concentrates will be sourced from pharmaceutical companies and independent investigators. All factor concentrate manufacturers, hemophilia treatment centers (HTCs), and independent investigators (identified via a systematic review of the literature) having on file pharmacokinetic data and willing to contribute full or sparse pharmacokinetic data will be eligible for participation. Multicompartmental modeling will be performed using a mixed-model approach for derivation and Bayesian forecasting for estimation of individual sparse data. NONMEM (ICON Development Solutions) will be used as modeling software. The WAPPS-Hemo research network has been launched and is currently joined by 30 HTCs from across the world. We have gathered dense individual pharmacokinetic data on 878 subjects, including several replicates, on 21 different molecules from 17 different sources. We have collected sparse individual pharmacokinetic data on 289 subjects from the participating centers through the testing phase of the WAPPS-Hemo Web interface. We have developed prototypal population pharmacokinetics models for 11 molecules. The WAPPS-Hemo website (available at www.wapps-hemo.org, version 2.4), with core functionalities allowing hemophilia treaters to obtain individual pharmacokinetic estimates on sparse data points after 1 or more infusions of a factor concentrate, was launched for use within the research network in July 2015. The WAPPS-Hemo project and research network aims to make it easier to perform individual pharmacokinetic assessments on a reduced number of plasma samples by adoption of a population pharmacokinetics approach. The project will also gather data to substantially enhance the current knowledge about factor concentrate pharmacokinetics and sources of its variability in target populations. ClinicalTrials.gov NCT02061072; https://clinicaltrials.gov/ct2/show/NCT02061072 (Archived by WebCite at http://www.webcitation.org/6mRK9bKP6). ©Alfonso Iorio, Arun Keepanasseril, Gary Foster, Tamara Navarro-Ruan, Alanna McEneny-King, Andrea N Edginton, Lehana Thabane. Originally published in JMIR Research Protocols (http://www.researchprotocols.org), 15.12.2016.
Farré, Nuria; Vela, Emili; Clèries, Montse; Bustins, Montse; Cainzos-Achirica, Miguel; Enjuanes, Cristina; Moliner, Pedro; Ruiz, Sonia; Verdú-Rotellar, Jose Maria; Comín-Colet, Josep
2016-09-01
Heart failure (HF) is one of the diseases with greater healthcare expenditure. However, little is known about the cost of HF at a population level. Hence, our aim was to study the population-level distribution and predictors of healthcare expenditure in patients with HF. This was a population-based longitudinal study including all prevalent HF cases in Catalonia (Spain) on 31 December 2012 (n = 88 195). We evaluated 1-year healthcare resource use and expenditure using the Health Department (CatSalut) surveillance system that collects detailed information on healthcare usage for the entire population. Mean age was 77.4 (12) years; 55% were women. One-year mortality rate was 14%. All-cause emergency department visits and unplanned hospitalizations were required at least once in 53.4% and 30.8% of patients, respectively. During 2013, a total of €536.2 million were spent in the care of HF patients (7.1% of the total healthcare budget). The main source of expenditure was hospitalization (39% of the total) whereas outpatient care represented 20% of the total expenditure. In the general population, outpatient care and hospitalization were the main expenses. In multivariate analysis, younger age, higher presence of co-morbidities, and a recent HF or all-cause hospitalization were independently associated with higher healthcare expenditure. In Catalonia, a large portion of the annual healthcare budget is devoted to HF patients. Unplanned hospitalization represents the main source of healthcare-related expenditure. The knowledge of how expenditure is distributed in a non-selected HF population might allow health providers to plan the distribution of resources in patients with HF. © 2016 The Authors. European Journal of Heart Failure © 2016 European Society of Cardiology.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Harris, G.
1994-09-01
This is the third volume in a series of three volumes characterizing the population of sealed sources that may become greater-than-Class C low-level radioactive waste (GTCC LLW). In this volume, those sources possessed by general licensees are discussed. General-licensed devices may contain sealed sources with significant amounts of radioactive material. However, the devices are designed to be safe to use without special knowledge of radiological safety practices. Devices containing Am-241 or Cm-244 sources are most likely to become GTCC LLW after concentration averaging. This study estimates that there are about 16,000 GTCC devices held by general licensees; 15,000 of thesemore » contain Am-241 sources and 1,000 contain Cm-244 sources. Additionally, this study estimates that there are 1,600 GTCC devices sold to general licensees each year. However, due to a lack of available information on general licensees in Agreement States, these estimates are uncertain. This uncertainty is quantified in the low and high case estimates given in this report, which span approximately an order of magnitude.« less
Human Occupancy as a Source of Indoor Airborne Bacteria
Hospodsky, Denina; Qian, Jing; Nazaroff, William W.; Yamamoto, Naomichi; Bibby, Kyle; Rismani-Yazdi, Hamid; Peccia, Jordan
2012-01-01
Exposure to specific airborne bacteria indoors is linked to infectious and noninfectious adverse health outcomes. However, the sources and origins of bacteria suspended in indoor air are not well understood. This study presents evidence for elevated concentrations of indoor airborne bacteria due to human occupancy, and investigates the sources of these bacteria. Samples were collected in a university classroom while occupied and when vacant. The total particle mass concentration, bacterial genome concentration, and bacterial phylogenetic populations were characterized in indoor, outdoor, and ventilation duct supply air, as well as in the dust of ventilation system filters and in floor dust. Occupancy increased the total aerosol mass and bacterial genome concentration in indoor air PM10 and PM2.5 size fractions, with an increase of nearly two orders of magnitude in airborne bacterial genome concentration in PM10. On a per mass basis, floor dust was enriched in bacterial genomes compared to airborne particles. Quantitative comparisons between bacterial populations in indoor air and potential sources suggest that resuspended floor dust is an important contributor to bacterial aerosol populations during occupancy. Experiments that controlled for resuspension from the floor implies that direct human shedding may also significantly impact the concentration of indoor airborne particles. The high content of bacteria specific to the skin, nostrils, and hair of humans found in indoor air and in floor dust indicates that floors are an important reservoir of human-associated bacteria, and that the direct particle shedding of desquamated skin cells and their subsequent resuspension strongly influenced the airborne bacteria population structure in this human-occupied environment. Inhalation exposure to microbes shed by other current or previous human occupants may occur in communal indoor environments. PMID:22529946
Jackson, Michael L.; Jackson, Lisa A.; Kieke, Burney; McClure, David; Gaglani, Manjusha; Murthy, Kempapura; Malosh, Ryan; Monto, Arnold; Zimmerman, Richard K.; Foppa, Ivo M.; Flannery, Brendan; Thompson, Mark G.
2018-01-01
Background We estimated the burden of outpatient influenza and cases prevented by vaccination during the 2011/12 and 2012/13 influenza seasons using data from the United States Influenza Vaccine Effectiveness (US Flu VE) Network. Methods We defined source populations of persons who could seek care for acute respiratory illness (ARI) at each of the five US Flu VE Network sites. We identified all members of the source population who were tested for influenza during US Flu VE influenza surveillance. Each influenza-positive subject received a sampling weight based on the proportion of source population members who were tested for influenza, stratified by site, age, and other factors. We used the sampling weights to estimate the cumulative incidence of medically attended influenza in the source populations. We estimated cases averted by vaccination using estimates of cumulative incidence, vaccine coverage, and vaccine effectiveness. Results Cumulative incidence of medically attended influenza ranged from 0.8% to 2.8% across sites during 2011/12 and from 2.6% to 6.5% during the 2012/13 season. Stratified by age, incidence ranged from 1.2% among adults 50 years of age and older in 2011/12 to 10.9% among children 6 months to 8 years of age in 2012/13. Cases averted by vaccination ranged from 4 to 41 per 1,000 vaccinees, depending on the study site and year. Conclusions The incidence of medically attended influenza varies greatly by year and even by geographic region within the same year. The number of cases averted by vaccination varies greatly based on overall incidence and on vaccine coverage. PMID:26271827
Far-ultraviolet observation of the globular cluster NGC 6397
NASA Astrophysics Data System (ADS)
Dieball, A.; Rasekh, A.; Knigge, C.; Shara, M.; Zurek, D.
2017-07-01
We present an observational far-ultraviolet (FUV) and near-ultraviolet (NUV) study of the core region of the globular cluster (GC) NGC 6397. The observations were obtained with the Space Telescope Imaging Spectrograph (STIS, FUV) and the Wide Field Camera 3 (NUV) on board the Hubble Space Telescope. Here, we focus on the UV-bright stellar populations such as blue stragglers (BSs), white dwarfs (WDs) and cataclysmic variables (CVs). We present the first FUV - NUV colour-magnitude diagram (CMD) for this cluster. To support our classification of the stellar populations, we compare our FUV - NUV CMD with optical data from the ACS Survey of Galactic Globular Clusters. The FUV - NUV CMD indicates 16 sources located in the WD area, and 10 BSs within the 25 × 25 arcsec2 of the STIS FUV data. 18 Chandra X-ray sources are located within the FUV field of view. 13 of those have an NUV counterpart, of which 9 sources also have an FUV counterpart. Out of those, five sources are previously suggested CVs, and indeed, all five are located in the WD/CV region in our FUV - NUV CMD. Another CV has only an FUV but no NUV counterpart. We also detect an NUV (but no FUV) counterpart to the millisecond pulsar (MSP) located in the core of this cluster. The NUV light curves of the CVs and MSP show flickering behaviour typical of CVs. We found that the BSs and CVs are the most centrally concentrated populations. This might be an effect of mass segregation or it might indicate the preferred birth place of BSs and CVs via dynamical interactions in the dense core region of GCs. Horizontal branch stars are the least centrally concentrated population and absent in the innermost area of the core.
USDA-ARS?s Scientific Manuscript database
The intake of carbohydrates has been evaluated cross-sectionally, but not longitudinally in an ageing American adult population. The aim of the present study was to examine trends in the intake of dietary carbohydrates and their major food sources among the Framingham Heart Study Offspring (FOS) coh...
Drinking cholera: salinity levels and palatability of drinking water in coastal Bangladesh.
Grant, Stephen Lawrence; Tamason, Charlotte Crim; Hoque, Bilqis Amin; Jensen, Peter Kjaer Mackie
2015-04-01
To measure the salinity levels of common water sources in coastal Bangladesh and explore perceptions of water palatability among the local population to investigate the plausibility of linking cholera outbreaks in Bangladesh with ingestion of saline-rich cholera-infected river water. Hundred participants took part in a taste-testing experiment of water with varying levels of salinity. Salinity measurements were taken of both drinking and non-drinking water sources. Informal group discussions were conducted to gain an in-depth understanding of water sources and water uses. Salinity levels of non-drinking water sources suggest that the conditions for Vibrio cholerae survival exist 7-8 days within the local aquatic environment. However, 96% of participants in the taste-testing experiment reported that they would never drink water with salinity levels that would be conducive to V. cholerae survival. Furthermore, salinity levels of participant's drinking water sources were all well below the levels required for optimal survival of V. cholerae. Respondents explained that they preferred less salty and more aesthetically pleasing drinking water. Theoretically, V. cholerae can survive in the river systems in Bangladesh; however, water sources which have been contaminated with river water are avoided as potential drinking water sources. Furthermore, there are no physical connecting points between the river system and drinking water sources among the study population, indicating that the primary driver for cholera cases in Bangladesh is likely not through the contamination of saline-rich river water into drinking water sources. © 2015 John Wiley & Sons Ltd.
Marsh, Alan J.; O’Sullivan, Orla; Hill, Colin; Ross, R. Paul; Cotter, Paul D.
2013-01-01
Kefir is a fermented milk-based beverage to which a number of health-promoting properties have been attributed. The microbes responsible for the fermentation of milk to produce kefir consist of a complex association of bacteria and yeasts, bound within a polysaccharide matrix, known as the kefir grain. The consistency of this microbial population, and that present in the resultant beverage, has been the subject of a number of previous, almost exclusively culture-based, studies which have indicated differences depending on geographical location and culture conditions. However, culture-based identification studies are limited by virtue of only detecting species with the ability to grow on the specific medium used and thus culture-independent, molecular-based techniques offer the potential for a more comprehensive analysis of such communities. Here we describe a detailed investigation of the microbial population, both bacterial and fungal, of kefir, using high-throughput sequencing to analyse 25 kefir milks and associated grains sourced from 8 geographically distinct regions. This is the first occasion that this technology has been employed to investigate the fungal component of these populations or to reveal the microbial composition of such an extensive number of kefir grains or milks. As a result several genera and species not previously identified in kefir were revealed. Our analysis shows that the bacterial populations in kefir are dominated by 2 phyla, the Firmicutes and the Proteobacteria. It was also established that the fungal populations of kefir were dominated by the genera Kazachstania, Kluyveromyces and Naumovozyma, but that a variable sub-dominant population also exists. PMID:23894461
Marsh, Alan J; O'Sullivan, Orla; Hill, Colin; Ross, R Paul; Cotter, Paul D
2013-01-01
Kefir is a fermented milk-based beverage to which a number of health-promoting properties have been attributed. The microbes responsible for the fermentation of milk to produce kefir consist of a complex association of bacteria and yeasts, bound within a polysaccharide matrix, known as the kefir grain. The consistency of this microbial population, and that present in the resultant beverage, has been the subject of a number of previous, almost exclusively culture-based, studies which have indicated differences depending on geographical location and culture conditions. However, culture-based identification studies are limited by virtue of only detecting species with the ability to grow on the specific medium used and thus culture-independent, molecular-based techniques offer the potential for a more comprehensive analysis of such communities. Here we describe a detailed investigation of the microbial population, both bacterial and fungal, of kefir, using high-throughput sequencing to analyse 25 kefir milks and associated grains sourced from 8 geographically distinct regions. This is the first occasion that this technology has been employed to investigate the fungal component of these populations or to reveal the microbial composition of such an extensive number of kefir grains or milks. As a result several genera and species not previously identified in kefir were revealed. Our analysis shows that the bacterial populations in kefir are dominated by 2 phyla, the Firmicutes and the Proteobacteria. It was also established that the fungal populations of kefir were dominated by the genera Kazachstania, Kluyveromyces and Naumovozyma, but that a variable sub-dominant population also exists.
Hyshka, Elaine; Karekezi, Kamagaju; Tan, Benjamin; Slater, Linda G; Jahrig, Jesse; Wild, T Cameron
2017-03-20
A growing body of research assesses population need for substance use services. However, the extent to which survey research incorporates expert versus consumer perspectives on service need is unknown. We conducted a large, international review to (1) describe extant research on population need for substance use services, and the extent to which it incorporates expert and consumer perspectives on service need, (2) critically assess methodological and measurement approaches used to study consumer-defined need, and (3) examine the potential for existing research that prioritizes consumer perspectives to inform substance use service system planning. Systematic searches of seven databases identified 1930 peer-reviewed articles addressing population need for substance use services between January 1980 and May 2015. Empirical studies (n = 1887) were categorized according to source(s) of data used to derive population estimates of service need (administrative records, biological samples, qualitative data, and/or quantitative surveys). Quantitative survey studies (n = 1594) were categorized as to whether service need was assessed from an expert and/or consumer perspective; studies employing consumer-defined need measures (n = 217) received further in-depth quantitative coding to describe study designs and measurement strategies. Almost all survey studies (96%; n = 1534) used diagnostically-oriented measures derived from an expert perspective to assess service need. Of the small number (14%, n = 217) of survey studies that assessed consumer's perspectives, most (77%) measured perceived need for generic services (i.e. 'treatment'), with fewer (42%) examining self-assessed barriers to service use, or informal help-seeking from family and friends (10%). Unstandardized measures were commonly used, and very little research was longitudinal or tested hypotheses. Only one study used a consumer-defined need measure to estimate required service system capacity. Rhetorical calls for including consumer perspectives in substance use service system planning are belied by the empirical literature, which is dominated by expert-driven approaches to measuring population need. Studies addressing consumer-defined need for substance use services are conceptually underdeveloped, and exhibit methodological and measurement weaknesses. Further scholarship is needed to integrate multidisciplinary perspectives in this literature, and fully realize the promise of incorporating consumer perspectives into substance use service system planning.
Lavieri, Nicolas A; Sebranek, Joseph G; Cordray, Joseph C; Dickson, James S; Horsch, Ashley M; Jung, Stephanie; Manu, David K; Brehm-Stecher, Byron F; Mendonça, Aubrey F
2014-05-01
Sodium nitrite exerts an inhibitory effect on the growth of Listeria monocytogenes. The objective of this study was to investigate the effects of various nitrite concentrations from a vegetable source with and without high hydrostatic pressure (HHP) on the recovery and growth of L. monocytogenes on ready-to-eat restructured ham. A preconverted celery powder was used as the vegetable source of nitrite. Targeted concentrations of natural nitrite investigated were 0, 50, and 100 mg/kg. HHP treatments evaluated were 400 MPa for 4 min and 600 MPa for 1 or 4 min at 12 ± 2 °C (initial temperature of the pressurization fluid). Viable L. monocytogenes populations were monitored on modified Oxford medium and thin agar layer medium through 98 days of storage at 4 ± 1 °C. Populations on both media did not differ. The HHP treatment at 600 MPa for 4 min resulted in L. monocytogenes populations below the detection limit of our sampling protocols throughout the storage period regardless of the natural nitrite concentration. The combination of HHP at 400 MPa for 4 min or 600 MPa for 1 min with natural nitrite resulted in initial inhibition of viable L. monocytogenes. Ham formulations that did not contain natural nitrite allowed faster growth of L. monocytogenes than did those with nitrite, regardless of whether they were treated with HHP. The results indicate that nitrite from a vegetable source at the concentrations used in this study resulted in slower growth of this microorganism. HHP treatments enhanced the inhibitory effects of natural nitrite on L. monocytogenes growth. Thus, the combination of natural nitrite plus HHP appears to have a synergistic inhibitory effect on L. monocytogenes growth.
Islam, Salwa; Fitzgerald, Lisa
2016-01-01
High rates of obesity are a significant issue amongst Indigenous populations in many countries around the world. Media framing of issues can play a critical role in shaping public opinion and government policy. A broad range of media analyses have been conducted on various aspects of obesity, however media representation of Indigenous obesity remains unexplored. In this study we investigate how obesity in Australia's Indigenous population is represented in newsprint media coverage. Media articles published between 2007 and 2014 were analysed for the distribution and extent of coverage over time and across Indigenous and mainstream media sources using quantitative content analysis. Representation of the causes and solutions of Indigenous obesity and framing in text and image content was examined using qualitative framing analysis. Media coverage of Indigenous obesity was very limited with no clear trends in reporting over time or across sources. The single Indigenous media source was the second largest contributor to the media discourse of this issue. Structural causes/origins were most often cited and individual solutions were comparatively overrepresented. A range of frames were employed across the media sources. All images reinforced textual framing except for one article where the image depicted individual factors whereas the text referred to structural determinants. This study provides a starting point for an important area of research that needs further investigation. The findings highlight the importance of alternative news media outlets, such as The Koori Mail, and that these should be developed to enhance the quality and diversity of media coverage. Media organisations can actively contribute to improving Indigenous health through raising awareness, evidence-based balanced reporting, and development of closer ties with Indigenous health workers.
Dietary intake and food sources of fatty acids in Australian adolescents.
O'Sullivan, Therese A; Ambrosini, Gina; Beilin, Lawrie J; Mori, Trevor A; Oddy, Wendy H
2011-02-01
Dietary fat consumed during childhood and adolescence may be related to the development of cardiovascular and other chronic diseases in adulthood; however, there is a lack of information on specific fatty acid intakes and food sources in these populations. Our study aimed to assess fatty acid intakes in Australian adolescents, compare intakes with national guidelines, and identify major food sources of fatty acids. Dietary intake was assessed using measured 3-d records in 822 adolescents aged 13-15 y participating in The Western Australian Pregnancy Cohort (Raine) Study, Australia. Mean daily total fat intakes were 90 ± 25 g for boys and 73 ± 20 g for girls, with saturated fat contributing 14% of total energy intake. Mean contribution to daily energy intake for linoleic, alpha-linolenic, eicosapentaenoic, docosapentaenoic, and docosahexaenoic acids were 3.0%, 0.40%, 0.02%, 0.01%, and 0.04%, respectively, for boys, and 3.3%, 0.42%, 0.02%, 0.01%, and 0.05% for girls. To meet guidelines for chronic disease prevention, consumption of long-chain omega-3 fatty acids in this population may need to increase up to three-fold and the proportion of saturated fat decrease by one-third. Girls were more likely to achieve the guidelines. Major food sources were dairy products for total fat, saturated fat and alpha-linolenic acid, margarines for linoleic acid, and fish for long-chain omega-3 fatty acids. Results suggest that for this population, a higher dietary intake of long-chain omega-3 fatty acids, particularly for boys, and lower proportion of saturated fat is required to meet recommendations for prevention of chronic disease. Copyright © 2011 Elsevier Inc. All rights reserved.
Holá, Eva; Košnar, Jiří; Kučera, Jan
2015-01-01
Patterns of genetic variation and spatial genetic structure (SGS) were investigated in Crossocalyx hellerianus, a strictly epixylic dioicous liverwort (Scapaniaceae s.l., Marchantiophyta). Studied populations were located in Fennoscandia and Central Europe, with localities differing in availability of substrate and the population connectivity, and their populations consequently different in size, density, and prevailing reproductive mode. A set of nine polymorphic microsatellites was successfully developed and used. Identical individuals were only found within populations. Especially in large populations, the majority of the individuals were genetically unique. Resampled number of genotypes, mean number of observed alleles per locus after rarefaction, and Nei's gene diversity in large populations reached high values and ranged between 4.41-4.97, 3.13-4.45, and 0.94-0.99, respectively. On the contrary, the values in small populations were lower and ranged between 1.00-4.42, 1.00-2.73, and 0.00-0.95, respectively. As expected, large populations were found to be more genetically diverse than small populations but relatively big diversity of genotypes was also found in small populations. This indicated that even small populations are important sources of genetic variation in bryophytes and processes causing loss of genetic variation might be compensated by other sources of variability, of which somatic mutations might play an important role. The presence of SGS was discovered in all populations. Large populations possessed less SGS, with individuals showing a pronounced decrease in kinship over 50 cm of distance. Apparent SGS of small populations even at distances up to 16 meters suggests the aggregation of similar genotypes, caused predominantly by the deposition of asexually formed gemmae. Although no strong kinship was detectable at the distances over 16 meters in both small and large populations, identical genotypes were occasionally detected at longer distances (20-80 m), suggesting effective dispersal of asexual propagules.
Holá, Eva; Košnar, Jiří; Kučera, Jan
2015-01-01
Patterns of genetic variation and spatial genetic structure (SGS) were investigated in Crossocalyx hellerianus, a strictly epixylic dioicous liverwort (Scapaniaceae s.l., Marchantiophyta). Studied populations were located in Fennoscandia and Central Europe, with localities differing in availability of substrate and the population connectivity, and their populations consequently different in size, density, and prevailing reproductive mode. A set of nine polymorphic microsatellites was successfully developed and used. Identical individuals were only found within populations. Especially in large populations, the majority of the individuals were genetically unique. Resampled number of genotypes, mean number of observed alleles per locus after rarefaction, and Nei’s gene diversity in large populations reached high values and ranged between 4.41–4.97, 3.13–4.45, and 0.94–0.99, respectively. On the contrary, the values in small populations were lower and ranged between 1.00–4.42, 1.00–2.73, and 0.00–0.95, respectively. As expected, large populations were found to be more genetically diverse than small populations but relatively big diversity of genotypes was also found in small populations. This indicated that even small populations are important sources of genetic variation in bryophytes and processes causing loss of genetic variation might be compensated by other sources of variability, of which somatic mutations might play an important role. The presence of SGS was discovered in all populations. Large populations possessed less SGS, with individuals showing a pronounced decrease in kinship over 50 cm of distance. Apparent SGS of small populations even at distances up to 16 meters suggests the aggregation of similar genotypes, caused predominantly by the deposition of asexually formed gemmae. Although no strong kinship was detectable at the distances over 16 meters in both small and large populations, identical genotypes were occasionally detected at longer distances (20–80 m), suggesting effective dispersal of asexual propagules. PMID:26186214
eHealth Trends in Europe 2005-2007: A Population-Based Survey
Chronaki, Catherine E; Lausen, Berthold; Prokosch, Hans-Ulrich; Rasmussen, Janne; Santana, Silvina; Staniszewski, Andrzej; Wangberg, Silje Camilla
2008-01-01
Background In the last decade, the number of Internet users worldwide has dramatically increased. People are using the Internet for various health-related purposes. It is important to monitor such use as it may have an impact on the individual’s health and behavior, patient-practitioner roles, and on general health care provision. Objectives This study investigates trends and patterns of European health-related Internet use over a period of 18 months. The main study objective was to estimate the change in the proportion of the population using the Internet for health purposes, and the importance of the Internet as a source of health information compared to more traditional sources. Methods The survey data were collected through computer-assisted telephone interviews. A representative sample (N = 14,956) from seven European countries has been used: Denmark, Germany, Greece, Latvia, Norway, Poland, and Portugal. The European eHealth Consumer Trends Survey was first conducted in October-November 2005 and repeated in April-May 2007. In addition to providing background information, respondents were asked to rate the importance of various sources of health information. They were also queried as to the frequency of different online activities related to health and illness and the effects of such use on their disposition. Results The percentage of the population that has used the Internet for health purposes increased from an estimated 42.3% (95% CI [Confidence Interval] 41.3 - 43.3) in 2005 to an estimated 52.2% (95% CI 51.3 - 53.2) in 2007. Significant growth in the use of the Internet for health purposes was found in all the seven countries. Young women are the most active Internet health users. The importance of the Internet as a source of health information has increased. In 2007, the Internet was perceived as an important source of health information by an estimated 46.8% (95% CI 45.7 - 47.9) of the population, a significant increase of 6.5 % (95% CI 4.9 - 8.1) from 2005. The importance of all the traditional health information channels has either decreased or remained the same. An estimated 22.7% (95% CI 21.7 - 23.6) are using it for more interactive services than just reading health information. Conclusion The Internet is increasingly being used as a source of health information by the European population, and its perceived importance is rising. Use of the Internet for health purposes is growing in all age groups and for both men and women, with especially strong growth among young women. We see that experienced Internet health users are also using the Internet as an active communication channel, both for reaching health professionals and for communicating with peers. PMID:19017584
Olza, Josune; Aranceta-Bartrina, Javier; González-Gross, Marcela; Ortega, Rosa M; Serra-Majem, Lluis; Varela-Moreiras, Gregorio; Gil, Ángel
2017-07-06
Zinc, selenium, and the vitamins A, E and C, all have specific biological functions that are involved mainly in the antioxidant defence system, which has important implications for the development of chronic diseases. We aimed to assess the reported intake of those six nutrients, as well as the food that contributes to their sources of intakes. Data were obtained from the Spanish ANIBES ("Anthropometry, Intake and Energy Balance in Spain") study, n = 2009 (9-75 years old). The analyses were performed in the whole population and in the plausible energy reporters after a misreporting analysis according to the European Food and Safety Authority (EFSA) protocol. A validated, photo-based three-day food record was used to collect the data. Mean (max-min) reported intake for the whole population of zinc was 8.1 ± 0.1 mg/day, (2.3-27.3 mg/day), selenium 75 ± 1 µg/day, (14-265 µg/day), vitamin A 668 µg RE/day (2-11,017 µg RE/day), retinol 364 ± 18 µg/day (0-10,881 µg/day), carotenes 1735 ± 35 µg/day (13-13,962 µg/day), vitamin E 7.0 ± 0.1 mg α-TE/day (0.7-55.2 mg α-TE/day) and vitamin C 84.4 ± 1.4 mg/day (5.0-802.7 mg/day). The main source intakes for zinc were meat and meat products, for selenium cereals and grains, for vitamin E oils and fat, and for vitamin A and C vegetables. There is an elevated percentage of the Spanish ANIBES population not meeting the EFSA recommended intakes for all analysed micronutrients: zinc (83%), vitamin A (60%), vitamin E (80%), vitamin C (36%) and selenium (25%).
Mineralogies and source regions of near-Earth asteroids
NASA Astrophysics Data System (ADS)
Dunn, Tasha L.; Burbine, Thomas H.; Bottke, William F.; Clark, John P.
2013-01-01
Near-Earth Asteroids (NEAs) offer insight into a size range of objects that are not easily observed in the main asteroid belt. Previous studies on the diversity of the NEA population have relied primarily on modeling and statistical analysis to determine asteroid compositions. Olivine and pyroxene, the dominant minerals in most asteroids, have characteristic absorption features in the visible and near-infrared (VISNIR) wavelengths that can be used to determine their compositions and abundances. However, formulas previously used for deriving compositions do not work very well for ordinary chondrite assemblages. Because two-thirds of NEAs have ordinary chondrite-like spectral parameters, it is essential to determine accurate mineralogies. Here we determine the band area ratios and Band I centers of 72 NEAs with visible and near-infrared spectra and use new calibrations to derive the mineralogies 47 of these NEAs with ordinary chondrite-like spectral parameters. Our results indicate that the majority of NEAs have LL-chondrite mineralogies. This is consistent with results from previous studies but continues to be in conflict with the population of recovered ordinary chondrites, of which H chondrites are the most abundant. To look for potential correlations between asteroid size, composition, and source region, we use a dynamical model to determine the most probable source region of each NEA. Model results indicate that NEAs with LL chondrite mineralogies appear to be preferentially derived from the ν6 secular resonance. This supports the hypothesis that the Flora family, which lies near the ν6 resonance, is the source of the LL chondrites. With the exception of basaltic achondrites, NEAs with non-chondrite spectral parameters are slightly less likely to be derived from the ν6 resonance than NEAs with chondrite-like mineralogies. The population of NEAs with H, L, and LL chondrite mineralogies does not appear to be influenced by size, which would suggest that ordinary chondrites are not preferentially sourced from meter-sized objects due to Yarkovsky effect.
Hanamoto, Seiya; Nakada, Norihide; Yamashita, Naoyuki; Tanaka, Hiroaki
2018-02-15
Fifty-five pharmaceuticals were monitored at four rivers and inlets and/or outlets of three sewage treatment plants (STPs) in Yodo River watershed, Japan over 17 sampling events. Twenty-six quantified pharmaceuticals were classified by source and fate. The load per person (LPP) of nine pharmaceuticals, including six with observed mass balance in studied river stretch of <80%, was appreciably lower in river water (RW) than in the effluent (EF) of STPs (RW/EF <0.5), indicating that they were susceptible to in-stream attenuation in the study area, while the others were relatively conservative. The LPP of 12 pharmaceuticals in RW were within ±50% of that in EF. Because their mass loadings in rivers were correlated with human population in the catchment and most people use the sewer system, the major source of the 12 pharmaceuticals was considered to be STPs. The LPP of the three most labile pharmaceuticals in STPs (caffeine, theophylline, and acetaminophen) was >1.5 in RW/EF and <1.0 in RW/influent (IF) of STPs. Poorly treated sewage discharged from households without using the sewer system was considered to be influential source of the three pharmaceuticals. The LPP (RW/EF) of caffeine, a pharmaceutical contained in food and beverage, was considerably higher than that of the other two, and this is attributable to untreated gray water discharged at households using the night-soil treatment system. The LPP of two veterinary drugs (sulfamonomethoxine and lincomycin) were >1.5 (RW/EF) and >1.0 (RW/IF). Their mass loadings in rivers showed a positive correlation with swine population in the catchment, although sulfamonomethoxine is equally used in both cattle and swine farming. This was attributable to application of cattle excrement as manure, and lability of sulfamonomethoxine during composting processes. The major source of the two veterinary drugs was considered to be on-site treatment facilities of swine urine. Copyright © 2017 Elsevier B.V. All rights reserved.
Robins, Stephanie; Barr, Helena J; Idelson, Rachel; Lambert, Sylvie; Zelkowitz, Phyllis
2016-10-21
Many men lack knowledge about male infertility, and this may have consequences for their reproductive and general health. Men may prefer to seek health information online, but these sources of information vary in quality. The objective of this study is to determine if online sources of information regarding male infertility are readable, suitable, and of appropriate quality for Internet users in the general population. This study used a cross-sectional design to evaluate online sources resulting from search engine queries. The following categories of websites were considered: (1) Canadian fertility clinics, (2) North American organizations related to fertility, and (3) the first 20 results of Google searches using the terms "male infertility" and "male fertility preservation" set to the search locations worldwide, English Canada, and French Canada. Websites that met inclusion criteria (N=85) were assessed using readability indices, the Suitability Assessment of Materials (SAM), and the DISCERN tool. The associations between website affiliation (government, university/medical, non-profit organization, commercial/corporate, private practice) and Google placement to readability, suitability, and quality were also examined. None of the sampled websites met recommended levels of readability. Across all websites, the mean SAM score for suitability was 45.37% (SD 11.21), or "adequate", while the DISCERN mean score for quality was 43.19 (SD 10.46) or "fair". Websites that placed higher in Google obtained a higher overall score for quality with an r (58) value of -.328 and a P value of .012, but this position was not related to readability or suitability. In addition, 20% of fertility clinic websites did not include fertility information for men. There is a lack of high quality online sources of information on male fertility. Many websites target their information to women, or fail to meet established readability criteria for the general population. Since men may prefer to seek health information online, it is important that health care professionals develop high quality sources of information on male fertility for the general population.
Wilk, Jemma B; Lash, Timothy L
2007-01-01
An association between exposure to a risk factor and age-at-onset of disease may reflect an effect on the rate of disease occurrence or an acceleration of the disease process. The difference in age-at-onset arising from case-only studies, however, may also reflect secular trends in the prevalence of exposure to the risk factor. Comparisons of age-at-onset associated with risk factors are commonly performed in case series enrolled for genetic linkage analysis of late onset diseases. We describe how the results of age-at-onset studies of environmental risk factors reflect the underlying structure of the source population, rather than an association with age-at-onset, by contrasting the effects of coffee drinking and cigarette smoking on Parkinson disease age-at-onset with the effects on age-at-enrollment in a population based study sample. Despite earlier evidence to suggest a protective association of coffee drinking and cigarette smoking with Parkinson disease risk, the age-at-onset results are comparable to the patterns observed in the population sample, and thus a causal inference from the age-at-onset effect may not be justified. Protective effects of multivitamin use on PD age-at-onset are also shown to be subject to a bias from the relationship between age and multivitamin initiation. Case-only studies of age-at-onset must be performed with an appreciation for the association between risk factors and age and ageing in the source population. PMID:17408493
Physician-industry conflict of interest: public opinion regarding industry-sponsored research.
Fisher, Charles G; DiPaola, Christian P; Noonan, Vanessa K; Bailey, Christopher; Dvorak, Marcel F S
2012-07-01
The nature of physician-industry conflict of interest (COI) has become a source of considerable concern, but is often not discussed in the research setting. With reduced funding available from government and nonprofit sources, industry support has enthusiastically grown, but along with this comes the potential for COI that must be regulated. In this era of shared decision making in health care, society must have input into this regulation. The purpose of this study was to assess the opinions of a North American population sample on COI regarding industry-funded research and to analyze population subgroups for trends. A survey was developed for face and content validity, underwent focus group evaluation for clarity and bias reduction, and was administered via the World Wide Web. Demographic and general survey results were summarized as a percentage for each answer, and subgroup analysis was done using logistic regression. Generalizability of the sample to the US population was also assessed. Of 541 surveys, 40 were excluded due to missing information, leaving 501 surveys for analysis. The sample population was composed of more females, was older, and was more educated than a representative cross-section of the American population. Respondents support multidisciplinary surgeon-industry COI regulation and trust doctors and their professional societies the most to head this effort. Respondents trust government officials and company representatives the least with respect to regulation of COI. Most respondents feel that industry-sponsored research can involve physicians and be both objective and beneficial to patients. Most respondents in this study felt that surgeons should be involved in industry-sponsored research and that more research, regardless of funding source, will ultimately benefit patients. The majority of respondents distrust government or industry to regulate COI. The development of evidence-based treatment recommendations requires the inclusion of patient preference. The authors encourage regulatory bodies to follow suit and include society's perspective on regulation of COI in research.
Referred knee pain in a young athlete: a case study.
Tippett, S R
1994-02-01
Parapatellar pain is a common complaint in the active adolescent patient population. Patello-femoral pain syndrome, Osgood-Schlatter disease, Sinding-Larsen-Johansson syndrome, patellar tendinitis, and other stress failure conditions are the primary causes of these parapatellar symptoms. Not all cases of knee discomfort are related to knee pathology. This case study discusses hip pathology as a source of referred knee pain in an 8-year-old male athlete. Care must be taken to evaluate all possible sources of both primary and referred pain in all cases.
Listman, Jennifer B; Hasin, Deborah; Kranzler, Henry R; Malison, Robert T; Mutirangura, Apiwat; Sughondhabirom, Atapol; Aharonovich, Efrat; Spivak, Baruch; Gelernter, Joel
2010-06-14
Detecting population substructure is a critical issue for association studies of health behaviors and other traits. Whether inherent in the population or an artifact of marker choice, determining aspects of a population's genetic history as potential sources of substructure can aid in design of future genetic studies. Jewish populations, among which association studies are often conducted, have a known history of migrations. As a necessary step in understanding population structure to conduct valid association studies of health behaviors among Israeli Jews, we investigated genetic signatures of this history and quantified substructure to facilitate future investigations of these phenotypes in this population. Using 32 autosomal STR markers and the program STRUCTURE, we differentiated between Ashkenazi (AJ, N = 135) and non-Ashkenazi (NAJ, N = 226) Jewish populations in the form of Northern and Southern geographic genetic components (AJ north 73%, south 23%, NAJ north 33%, south 60%). The ability to detect substructure within these closely related populations using a small STR panel was contingent on including additional samples representing major continental populations in the analyses. Although clustering programs such as STRUCTURE are designed to assign proportions of ancestry to individuals without reference population information, when Jewish samples were analyzed in the absence of proxy parental populations, substructure within Jews was not detected. Generally, for samples with a given grandparental country of birth, STRUCTURE assignment values to Northern, Southern, African and Asian clusters agreed with mitochondrial DNA and Y-chromosomal data from previous studies as well as historical records of migration and intermarriage.
2010-01-01
Background Detecting population substructure is a critical issue for association studies of health behaviors and other traits. Whether inherent in the population or an artifact of marker choice, determining aspects of a population's genetic history as potential sources of substructure can aid in design of future genetic studies. Jewish populations, among which association studies are often conducted, have a known history of migrations. As a necessary step in understanding population structure to conduct valid association studies of health behaviors among Israeli Jews, we investigated genetic signatures of this history and quantified substructure to facilitate future investigations of these phenotypes in this population. Results Using 32 autosomal STR markers and the program STRUCTURE, we differentiated between Ashkenazi (AJ, N = 135) and non-Ashkenazi (NAJ, N = 226) Jewish populations in the form of Northern and Southern geographic genetic components (AJ north 73%, south 23%, NAJ north 33%, south 60%). The ability to detect substructure within these closely related populations using a small STR panel was contingent on including additional samples representing major continental populations in the analyses. Conclusions Although clustering programs such as STRUCTURE are designed to assign proportions of ancestry to individuals without reference population information, when Jewish samples were analyzed in the absence of proxy parental populations, substructure within Jews was not detected. Generally, for samples with a given grandparental country of birth, STRUCTURE assignment values to Northern, Southern, African and Asian clusters agreed with mitochondrial DNA and Y-chromosomal data from previous studies as well as historical records of migration and intermarriage. PMID:20546593
Hu, G; Lu, M-H; Tuan, H A; Liu, W-C; Xie, M-C; McInerney, C E; Zhai, B-P
2017-06-01
Rice planthopper (RPH) populations of Nilaparvata lugens and Sogatella furcifera periodically have erupted across Asia. Predicting RPH population dynamics and identifying their source areas are crucial for the management of these migratory pests in China, but the origins of the migrants to temperate and subtropical regions in China remains unclear. In particular, their early migration to China in March and April have not yet been explored due to a lack of research data available from potential source areas, Central Vietnam and Laos. In this study, we examined the population dynamics and migratory paths of N. lugens and S. furcifera in Vietnam and South China in 2012 and 2013. Trajectory modeling showed that in March and April in 2012 and 2013, RPH emigrated from source areas in Central Vietnam where rice was maturing to the Red River Delta and South China. Early migrants originated from Southern Central Vietnam (14-16°N), but later most were from Northern Central Vietnam (16-19°N). Analysis of meteorological and light-trap data from Hepu in April (1977-2013) using generalized linear models showed that immigration increased with precipitation in Southern Central Vietnam in January, but declined with precipitation in Northern Central Vietnam in January. These results determined that the RPH originate from overwintering areas in Central Vietnam, but not from southernmost areas of Vietnam. Winter precipitation, rather than temperature was the most important factor determining the number of RPH migrants. Based on their similar population dynamics and low population densities in Central Vietnam, we further speculated that RPH migrate to track ephemeral food resources whilst simultaneously avoiding predators. Migrations do not seem to be initiated by interspecific competition, overcrowding or host deterioration. Nevertheless, S. furcifera establishes populations earlier than N. lugens South China, perhaps to compensate for interspecific competition. We provide new information that could assist with forecasting outbreaks and implementing control measures against these migratory pests.
Berger, Ruti; Wasserberg, Gideon; Warburg, Alon; Orshan, Laor; Kotler, Burt P
2014-08-01
Populations at the edge of their geographic distributions are referred to as peripheral populations. Very little attention has been given to this topic in the context of persistence of infectious disease in natural populations. In this study, we examined this question using zoonotic cutaneous leishmaniasis (ZCL) caused by Leishmania major in the Negev Desert of Israel as a model system. Here, we suggest that the regional persistence of Phlebotomus papatasi populations and L. major transmission in the Sede Boqer region could be explained through processes akin to sink-source and/or mainland-island metapopulation dynamics. Given its potentially enzootically superior ecological conditions, we hypothesize that the Zin Valley ecotope constitutes the "mainland" or the "source" patch for the Sede Boqer area where L. major transmission is persistent and resistant to local extinctions (die-outs) whereas the local sand fly populations on the Zin Plateau ("island patch" or "sink patch") are more prone to local extinctions. Between 2007 and 2008, we trapped sand flies and sand rats in the two areas and compared sand fly abundance and L. major infection prevalence in both. In both 2007 and 2008, sand fly abundance was high and continuous in the Zin Wadi but low and discontinuous in the Zin Plateau. Infection prevalence of sand rats was significantly higher in the Wadi (13%) compared with the Zin Plateau (3%). Minimum infection rate in sand flies did not differ significantly between the two areas. Overall, our results are consistent with the premise that the Zin Valley population is relatively robust in terms of L. major transmission, whereas transmission is potentially more tenuous in the plateau. Understanding the biotic and abiotic processes enabling the persistence of L. major and other vector-borne diseases in peripheral disease foci is important for predicting the effect of anthropogenic land use and climate change.
Reynolds, Michelle H.; Pearce, John M.; Lavretsky, Philip; Peters Jeffrey L,; Courtot, Karen; Seixas, Pedro P.
2015-01-01
Genetic diversity is assumed to reflect the evolutionary potential and adaptability of populations, and thus quantifying the genetic diversity of endangered species is useful for recovery programs. In particular, if conservation strategies include reintroductions, periodic genetic assessments are useful to evaluate whether management efforts have resulted in the maximization or loss of genetic variation within populations over generations. In this study, we collected blood, feather, and tissue samples during 1999–2009 and quantified genetic diversity for a critically endangered waterfowl species endemic to the Hawaiian archipelago, the Laysan teal or duck (Anas laysanensis; n = 239 individual birds sampled). The last extant population of this species at Laysan Island was sourced in 2004–2005 for a ‘wild to wild’ translocation of 42 individuals for an experimental reintroduction to Midway Atoll. To inform future management strategies, we compared genetic diversity sampled from the source population (n = 133 Laysan birds) including 23 of Midway’s founders and offspring of the translocated population 2–5 years post release (n = 96 Midway birds). We attempted to identify polymorphic markers by screening nuclear microsatellite (N = 83) and intronic loci (N = 19), as well as the mitochondrial control region (mtDNA) for a subset of samples. Among 83 microsatellite loci screened, six were variable. We found low nuclear variation consistent with the species’ historical population bottlenecks and sequence variation was observed at a single intron locus. We detected no variation within the mtDNA. We found limited but similar estimates of allelic richness (2.58 alleles per locus) and heterozygosity within islands. Two rare alleles found in the Laysan Island source population were not present in the Midway translocated group, and a rare allele was discovered in an individual on Midway in 2008. We found similar genetic diversity and low, but statistically significant, levels of differentiation (0.6%) between island populations suggesting that genetic drift (as a result of translocation-induced population bottlenecking) has had a limited effect within five years post-release. Our results have utility for informing translocation and genetic management decisions.
Carley, Alexandra; Stratman, Erik
2015-01-01
Farmers have substantial sun exposure and increased skin cancer risk but poor sun protection practices. There are few studies regarding the underlying factors that contribute to inadequate skin cancer prevention practices in the farming population, and minimal data to guide skin cancer awareness and educational interventions for this population. The purpose of this study was to assess skin cancer knowledge, sun protection behaviors and barriers, health care information sources, and the impact of skin cancer screening among midwestern farmers and nonfarmers. Individuals attending a free skin cancer screening during 2011 Wisconsin Farm Technology Days were surveyed for self-reported sun protection use, extent of sun exposure, and skin cancer and sun protection beliefs and knowledge. A total of 476 individuals participated in the study, including 194 farmers. Although farmers identified sun protection benefits, few reported optimal practices, with only 23% of farmers reporting sunscreen use always or frequently when out in the sun for 15 minutes or more. Common barriers to sun protection included discomfort with wearing long pants and long shirts, forgetfulness with sunscreen use, and inconvenience with wearing wide-brimmed hats. Higher knowledge scores in farmers were associated with better sun protection. Farmers utilized different sources of health care information compared with nonfarmers, including farm magazines and newspapers, radio, and farm organizations. Providers should consider the unique characteristics of the farming population to provide skin cancer prevention education that is tailored to the needs of this population, such as reminders for sunscreen use and resources for sun-protective hats that do not interfere with work. Among individuals without prior history of skin cancer, 34% of farmers and 22% of nonfarmers (P = .0127) were referred for additional evaluation due to identification of a concerning lesion at the screening event. Thus, farmers may preferentially benefit from skin cancer screening events, and this population should be targeted for additional screening events in the future. This study identifies unique characteristics of the farming population that can assist providers in caring for this population and guide the future development of skin cancer awareness, prevention, and screening initiatives to benefit farmers.
Most studies of animal responses to CO2-induced ocean acidification focus on isolated individuals or uniformly aged and conditioned cohorts that lack the complexities typical of wild populations. These studies have become the primary data source for meta-analytic predictions abo...
Internally Generated Revenue (IGR) and Effectiveness of University Administration in Nigeria
ERIC Educational Resources Information Center
Ofoegbu, Felicia I.; Alonge, Hezekiah O.
2016-01-01
The purpose of the study was mainly to identify the major sources and utilization of internally generated financial revenue by Nigerian University administrators. The population of the study consisted of all the 102 university administrators from the seventeen Federal Universities in Southern Nigeria. Descriptive statistics and Pearson Product…
Civil-Military Operations in the Post Conflict Environment: Northern Uganda Case Study
2011-12-01
used to provide direct assistance in stabilizing a situation and building self -sufficient capacity in the crisis area. According to the U.S. SSTR...are a source of soft power to influence the population and avoid using kinetic military power. By deterring the population away from an insurgency...militaries train their personnel to coordinate, while humanitarian employees emphasize self -reliance in their areas of expertise.100 This disparity
An application of a zero-inflated lifetime distribution with multiple and incomplete data sources
Hamada, M. S.; Margevicius, K. J.
2016-02-11
In this study, we analyze data sampled from a population of parts in which an associated anomaly can occur at assembly or after assembly. Using a zero-inflated lifetime distribution to fit left-censored and right-censored data as well data from a supplementary sample, we make predictions about the proportion of the population with anomalies today and in the future. Goodness-of-fit is also addressed.
Popova, L Iu; Lutskaia, N I; Bogucharov, A A; Bril'kov, A V; Pechurkin, N S
1992-01-01
The populational structure of the Escherichia coli strain Z905 containing the recombinant plasmid with the phenotype AprLux+ was studied in chemostat. It was shown that the stability of the ratio of plasmid containing cells and cells without plasmids depends in the first place on the presence of the selective factor (ampicillin) in the medium and on the sources of carbon and energy limiting growth.
Operational Design Cognitive Methodology: An Analysis of COMISAF 30 August 2009 Initial Assessment
2010-04-01
the set of characteristics, capabilities, and sources of power from which a system derives its moral or physical strength, freedom of action, and...objective must be the population.” 53 The population focused objective extends beyond just the basics of physical security. The whole of government...In Warfare Studies AY10 Coursebook , edited by Sharon McBride, 196-212. Maxwell AFB, AL: Air University Press, October 2009. Kem, Jack D
Cheng, Kun; Rong, Xiaoying; Pinto-Tomás, Adrián A.; Fernández-Villalobos, Marcela; Murillo-Cruz, Catalina
2014-01-01
Examining the population structure and the influence of recombination and ecology on microbial populations makes great sense for understanding microbial evolution and speciation. Streptomycetes are a diverse group of bacteria that are widely distributed in nature and a rich source of useful bioactive compounds; however, they are rarely subjected to population genetic investigations. In this study, we applied a five-gene-based multilocus sequence analysis (MLSA) scheme to 41 strains of Streptomyces albidoflavus derived from diverse sources, mainly insects, sea, and soil. Frequent recombination was detected in S. albidoflavus, supported by multiple lines of evidence from the pairwise homoplasy index (Φw) test, phylogenetic discordance, the Shimodaira-Hasegawa (SH) test, and network analysis, underpinning the predominance of homologous recombination within Streptomyces species. A strong habitat signal was also observed in both phylogenetic and Structure 2.3.3 analyses, indicating the importance of ecological difference in shaping the population structure. Moreover, all three habitat-associated groups, particularly the entomic group, demonstrated significantly reduced levels of gene flow with one another, generally revealing habitat barriers to recombination. Therefore, a combined effect of homologous recombination and ecology is inferred for S. albidoflavus, where dynamic evolution is at least partly balanced by the extent that differential distributions of strains among habitats limit genetic exchange. Our study stresses the significance of ecology in microbial speciation and reveals the coexistence of homologous recombination and ecological divergence in the evolution of streptomycetes. PMID:25416769
NASA Technical Reports Server (NTRS)
Maoz, Eyal; Grindlay, Jonathan E.
1995-01-01
The incompatibility of the properties of the X-ray background (XRB) with active galactic nuclei (AGNs) contributing approximately greater than 60% at energies of a few keV has often been interpreted as being due to a substantial contribution of a new population of yet unrecognized X-ray sources. The existence of such population has been recently suggested also by an analysis of very deep ROSAT observations which revealed a considerable excess of faint X-ray sources over that expected from QSO evolution models, and that the average spectrum of the resolved sources becomes harder with decreasing flux limit. These sources could be extragalactic in origin, but if they make a substantial contribution to the XRB then they must exhibit much weaker clustering than galaxies or QSOs in order to be consistent with the stringent constraints on source clustering imposed by autocorrelation analyses of the unresolved XRB. We investigate the possibility that the indicated new population of X-ray sources is Galactic in origin. Examining spherical halo and thick disk distributions, we derive the allowed properties of such populations which would resolve the discrepancy found in the number counts of faint sources and be consistent with observational constraints on the total background intensity, the XRB anisotropy, the number of unidentified bright sources, the Galaxy's total X-ray luminosity, and with the results of fluctuation analyses of the unresolved XRB. We find that a flattened Galactic halo (or a thick disk) distribution with a scale height of a few kpc is consistent with all the above requirements. The typical X-ray luminosity of the sources is approximately equal to 10(exp 30-31)ergs/s in the 0.5-2 keV band, the number density of sources in the solar vicinity is approximately 10(exp -4.5)pc(exp -3), their total number in the Galaxy is approximately 10(exp 8.5), and their total contribution to the Galaxy's X-ray luminosity is approximately 10(exp 39) ergs/s. We discuss the possible nature of these soures, including their being subdwarfs, low mass x-ray binaries (LMXBs), massive black holes, and old neutron stars. We argue that the inferred X-ray and optical luminosities of these sources, the slope of their energy spectrum, and the derived local number density and spatial distribution are all consistent with their being intrinsically faint cataclysmic variables with low accretion rates. We suggest a few possibilities for the origin of such population, including an origin from disrupted globular clusters or dark clusters. We make predictions and suggest tests that could either confirm or rule out our proposal in the near future.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Seale, Jonathan P.; Meixner, Margaret; Sewiło, Marta
Observations from the HERschel Inventory of the Agents of Galaxy Evolution (HERITAGE) have been used to identify dusty populations of sources in the Large and Small Magellanic Clouds (LMC and SMC). We conducted the study using the HERITAGE catalogs of point sources available from the Herschel Science Center from both the Photodetector Array Camera and Spectrometer (PACS; 100 and 160 μm) and Spectral and Photometric Imaging Receiver (SPIRE; 250, 350, and 500 μm) cameras. These catalogs are matched to each other to create a Herschel band-merged catalog and then further matched to archival Spitzer IRAC and MIPS catalogs from themore » Spitzer Surveying the Agents of Galaxy Evolution (SAGE) and SAGE-SMC surveys to create single mid- to far-infrared (far-IR) point source catalogs that span the wavelength range from 3.6 to 500 μm. There are 35,322 unique sources in the LMC and 7503 in the SMC. To be bright in the FIR, a source must be very dusty, and so the sources in the HERITAGE catalogs represent the dustiest populations of sources. The brightest HERITAGE sources are dominated by young stellar objects (YSOs), and the dimmest by background galaxies. We identify the sources most likely to be background galaxies by first considering their morphology (distant galaxies are point-like at the resolution of Herschel) and then comparing the flux distribution to that of the Herschel Astrophysical Terahertz Large Area Survey (ATLAS) survey of galaxies. We find a total of 9745 background galaxy candidates in the LMC HERITAGE images and 5111 in the SMC images, in agreement with the number predicted by extrapolating from the ATLAS flux distribution. The majority of the Magellanic Cloud-residing sources are either very young, embedded forming stars or dusty clumps of the interstellar medium. Using the presence of 24 μm emission as a tracer of star formation, we identify 3518 YSO candidates in the LMC and 663 in the SMC. There are far fewer far-IR bright YSOs in the SMC than the LMC due to both the SMC's smaller size and its lower dust content. The YSO candidate lists may be contaminated at low flux levels by background galaxies, and so we differentiate between sources with a high (“probable”) and moderate (“possible”) likelihood of being a YSO. There are 2493/425 probable YSO candidates in the LMC/SMC. Approximately 73% of the Herschel YSO candidates are newly identified in the LMC, and 35% in the SMC. We further identify a small population of dusty objects in the late stages of stellar evolution including extreme and post-asymptotic giant branch, planetary nebulae, and supernova remnants. These populations are identified by matching the HERITAGE catalogs to lists of previously identified objects in the literature. Approximately half of the LMC sources and one quarter of the SMC sources are too faint to obtain accurate ample FIR photometry and are unclassified.« less
NASA Astrophysics Data System (ADS)
de Oliveira Alves, Nilmara; Brito, Joel; Caumo, Sofia; Arana, Andrea; de Souza Hacon, Sandra; Artaxo, Paulo; Hillamo, Risto; Teinilä, Kimmo; Batistuzzo de Medeiros, Silvia Regina; de Castro Vasconcellos, Pérola
2015-11-01
The Brazilian Amazon represents about 40% of the world's remaining tropical rainforest. However, human activities have become important drivers of disturbance in that region. The majority of forest fire hotspots in the Amazon arc due to deforestation are impacting the health of the local population of over 10 million inhabitants. In this study we characterize western Amazonia biomass burning emissions through the quantification of 14 Polycyclic Aromatic Hydrocarbons (PAHs), Organic Carbon, Elemental Carbon and unique tracers of biomass burning such as levoglucosan. From the PAHs dataset a toxic equivalence factor is calculated estimating the carcinogenic and mutagenic potential of biomass burning emissions during the studied period. Peak concentration of PM10 during the dry seasons was observed to reach 60 μg m-3 on the 24 h average. Conversely, PM10 was relatively constant throughout the wet season indicating an overall stable balance between aerosol sources and sinks within the filter sampling resolution. Similar behavior is identified for OC and EC components. Levoglucosan was found in significant concentrations (up to 4 μg m-3) during the dry season. Correspondingly, the estimated lung cancer risk calculated during the dry seasons largely exceeded the WHO health-based guideline. A source apportionment study was carried out through the use of Absolute Principal Factor Analysis (APFA), identifying a three-factor solution. The biomass burning factor is found to be the dominating aerosol source, having 75.4% of PM10 loading. The second factor depicts an important contribution of several PAHs without a single source class and therefore was considered as mixed sources factor, contributing to 6.3% of PM10. The third factor was mainly associated with fossil fuel combustion emissions, contributing to 18.4% of PM10. This work enhances the knowledge of aerosol sources and its impact on climate variability and local population, on a site representative of the deforestation which occupies a significant fraction of the Amazon basin.
Rich, David Q
2017-03-01
To address limitations of observational epidemiology studies of air pollution and health effects, including residual confounding by temporal and spatial factors, several studies have taken advantage of 'natural experiments', where an environmental policy or air quality intervention has resulted in reductions in ambient air pollution concentrations. Researchers have examined whether the population impacted by these air quality improvements, also experienced improvements in various health indices (e.g. reduced morbidity/mortality). In this paper, I review key accountability studies done previously and new studies done over the past several years in Beijing, Atlanta, London, Ireland, and other locations, describing study design and analysis strengths and limitations of each. As new 'natural experiment' opportunities arise, several lessons learned from these studies should be applied when planning a new accountability study. Comparison of health outcomes during the intervention to both before and after the intervention in the population of interest, as well as use of a control population to assess whether any temporal changes in the population of interest were also seen in populations not impacted by air quality improvements, should aid in minimizing residual confounding by these long term time trends. Use of either detailed health records for a population, or prospectively collected data on relevant mechanistic biomarkers coupled with such morbidity/mortality data may provide a more thorough assessment of if the intervention beneficially impacted the health of the community, and if so by what mechanism(s). Further, prospective measurement of a large suite of air pollutants may allow a more thorough understanding of what pollutant source(s) is/are responsible for any health benefit observed. The importance of using multiple statistical analysis methods in each paper and the difference in how the timing of the air pollution/outcome association may impact which of these design features is most important is also discussed. Based on these and other lessons learned, researchers may provide a more epidemiologically rigorous evaluation of cause-specific health impacts of an air quality intervention or action. Copyright © 2016 Elsevier Ltd. All rights reserved.
Rich, David Q.
2017-01-01
To address limitations of observational epidemiology studies of air pollution and health effects, including residual confounding by temporal and spatial factors, several studies have taken advantage of ‘natural experiments’, where an environmental policy or air quality intervention has resulted in reductions in ambient air pollution concentrations. Researchers have examined whether the population impacted by these air quality improvements, also experienced improvements in various health indices (e.g. reduced morbidity/mortality). In this paper, I review key accountability studies done previously and new studies done over the past several years in Beijing, Atlanta, London, Ireland, and other locations, describing study design and analysis strengths and limitations of each. As new ‘natural experiment’ opportunities arise, several lessons learned from these studies should be applied when planning a new accountability study. Comparison of health outcomes during the intervention to both before and after the intervention in the population of interest, as well as use of a control population to assess whether any temporal changes in the population of interest were also seen in populations not impacted by air quality improvements, should aid in minimizing residual confounding by these long term time trends. Use of either detailed health records for a population, or prospectively collected data on relevant mechanistic biomarkers coupled with such morbidity/mortality data may provide a more thorough assessment of if the intervention beneficially impacted the health of the community, and if so by what mechanism(s). Further, prospective measurement of a large suite of air pollutants may allow a more thorough understanding of what pollutant source(s) is/are responsible for any health benefit observed. The importance of using multiple statistical analysis methods in each paper and the difference in how the timing of the air pollution/outcome association may impact which of these design features is most important is also discussed. Based on these and other lessons learned, researchers may provide a more epidemiologically rigorous evaluation of cause-specific health impacts of an air quality intervention or action. PMID:28089581
MODELING POPULATION EXPOSURES TO OUTDOOR SOURCES OF HAZARDOUS AIR POLLUTANTS
Accurate assessment of human exposures is an important part of environmental health effects research. However, most air pollution epidemiology studies rely upon imperfect surrogates of personal exposures, such as information based on available central-site outdoor concentration ...
Dogan, Serkan; Primorac, Dragan; Marjanović, Damir
2014-10-01
To explore the distribution and polymorphisms of 23 short tandem repeat (STR) loci on the Y chromosome in the Turkish population recently settled in Sarajevo, Bosnia and Herzegovina and to investigate its genetic relationships with the homeland Turkish population and neighboring populations. This study included 100 healthy unrelated male individuals from the Turkish population living in Sarajevo. Buccal swab samples were collected as a DNA source. Genomic DNA was extracted using the salting out method and amplification was performed using PowerPlex Y 23 amplification kit. The studied population was compared to other populations using pairwise genetic distances, which were represented with a multi-dimensional scaling plot. Haplotype and allele frequencies of the sample population were calculated and the results showed that all 100 samples had unique haplotypes. The most polymorphic locus was DYS458, and the least polymorphic DYS391. The observed haplotype diversity was 1.0000 ± 0.0014, with a discrimination capacity of 1.00 and the match probability of 0.01. Rst values showed that our sample population was closely related in both dimensions to the Lebanese and Iraqi populations, while it was more distant from Bosnian, Croatian, and Macedonian populations. Turkish population residing in Sarajevo could be observed as a representative Turkish population, since our results were consistent with those previously published for the homeland Turkish population. Also, this study once again proved that geographically close populations were genetically more related to each other.
Size and spatial distribution of stray dog population in the University of São Paulo campus, Brazil.
Dias, Ricardo Augusto; Guilloux, Aline Gil Alves; Borba, Mauro Riegert; Guarnieri, Maria Cristina de Lourdes; Prist, Ricardo; Ferreira, Fernando; Amaku, Marcos; Neto, José Soares Ferreira; Stevenson, Mark
2013-06-01
A longitudinal study was carried out to describe the size and spatial distribution of the stray dog population in the University of São Paulo campus, Brazil from November 2010 to November 2011. The campus is located within the urban area of São Paulo, the largest city of Brazil, with a population over 11 million. The 4.2 km(2) that comprise the university grounds are walled, with 10 access gates, allowing stray dogs to move in and out freely. Over 100,000 people and 50,000 vehicles circulate in the campus daily. Five observations were made during the study period, using a mark-resight method. The same route was performed in all observations, being traveled twice on each observation day. Observed animals were photographed and the sight coordinates were obtained using a GPS device. The estimated size of the stray dog population varied from 32 (CI 95% 23-56) to 56 (CI 95% 45-77) individuals. Differences between in- and outward dog movements influenced dog population estimates. Overlapping home ranges of docile dogs were observed in areas where most people circulate. An elusive group was observed close to a protected rain forest area and the estimated home range for this group did not overlap with the home ranges for other dogs within the campus. A kernel density map showed that higher densities of stray dog sighting is associated with large organic matter generators, such as university restaurants. We conclude that the preferred source of food of the stray dogs on the University of São Paulo campus was leftover food deliberately offered by restaurant users. The population was stable during the study period and the constant source of food was the main reason to retain this population within the campus. Copyright © 2012 Elsevier B.V. All rights reserved.
21-cm signature of the first sources in the Universe: prospects of detection with SKA
NASA Astrophysics Data System (ADS)
Ghara, Raghunath; Choudhury, T. Roy; Datta, Kanan K.
2016-07-01
Currently several low-frequency experiments are being planned to study the nature of the first stars using the redshifted 21-cm signal from the cosmic dawn and Epoch of Reionization. Using a one-dimensional radiative transfer code, we model the 21-cm signal pattern around the early sources for different source models, I.e. the metal-free Population III (PopIII) stars, primordial galaxies consisting of Population II (PopII) stars, mini-QSOs and high-mass X-ray binaries (HMXBs). We investigate the detectability of these sources by comparing the 21-cm visibility signal with the system noise appropriate for a telescope like the SKA1-low. Upon integrating the visibility around a typical source over all baselines and over a frequency interval of 16 MHz, we find that it will be possible to make a ˜9σ detection of the isolated sources like PopII galaxies, mini-QSOs and HMXBs at z ˜ 15 with the SKA1-low in 1000 h. The exact value of the signal-to-noise ratio (SNR) will depend on the source properties, in particular on the mass and age of the source and the escape fraction of ionizing photons. The predicted SNR decreases with increasing redshift. We provide simple scaling laws to estimate the SNR for different values of the parameters which characterize the source and the surrounding medium. We also argue that it will be possible to achieve an SNR ˜9 even in the presence of the astrophysical foregrounds by subtracting out the frequency-independent component of the observed signal. These calculations will be useful in planning 21-cm observations to detect the first sources.
Schäfer, Mike S; Füchslin, Tobias; Metag, Julia; Kristiansen, Silje; Rauchfleisch, Adrian
2018-01-01
Few studies have assessed whether populations can be divided into segments with different perceptions of science. We provide such an analysis and assess whether these segments exhibit specific patterns of media and information use. Based on representative survey data from Switzerland, we use latent class analysis to reconstruct four segments: the "Sciencephiles," with strong interest for science, extensive knowledge, and a pronounced belief in its potential, who use a variety of sources intensively; the "Critically Interested," also with strong interest and support for science but with less trust in it, who use similar sources but are more cautious toward them; the "Passive Supporters" with moderate levels of interest, trust, and knowledge and tempered perceptions of science, who use fewer sources; and the "Disengaged," who are not interested in science, do not know much about it, harbor critical views toward it, and encounter it-if at all-mostly through television.
Ectopic Pregnancy and Emergency Contraceptive Pills: A Systematic Review
Cleland, Kelly; Raymond, Elizabeth; Trussell, James; Cheng, Linan; Zhu, Haoping
2014-01-01
Objective To evaluate the existing data to estimate the rate of ectopic pregnancy among emergency contraceptive pill treatment failures. Data Sources Our initial reference list was generated from a 2008 Cochrane review of emergency contraception. In August 2009, we searched Biosys Previews, the Cochrane Database of Systematic Reviews, Medline, Global Health Database, Health Source: Popline, and Wanfang Data (a Chinese database). Methods of Study Selection This study included data from 136 studies which followed a defined population of women treated one time with emergency contraceptive pills (either mifepristone or levonorgestrel), and in which the number and location of pregnancies were ascertained. Results Data from each article were abstracted independently by two reviewers. In the studies of mifepristone, 3 out of 494 (0.6%) pregnancies were ectopic; in the levonorgestrel studies, 3 out of 307 (1%) were ectopic. Conclusion The rate of ectopic pregnancy when treatment with emergency contraceptive pills fails does not exceed the rate observed in the general population. Since emergency contraceptive pills are effective in lowering the risk of pregnancy, their use should reduce the chance that an act of intercourse will result in ectopic pregnancy. PMID:20502299
Fletcher, A E
2010-01-01
Cataract and age-related macular degeneration (AMD) are the major causes of vision impairment and blindness worldwide. Both conditions are strongly age related with earlier signs (usually asymptomatic) occurring in middle age and becoming severer and more prevalent with increasing age. The aetiology of these conditions is thought to fit with the 'free radical theory' of ageing which postulates that ageing and age-related diseases result from the accumulation of cellular damage from reactive oxygen species (ROS). Mitochondrial energy production is a major source of endogenous ROS. External sources of ROS include environmental sources especially solar radiation, biomass fuels and tobacco smoking. There is strong evidence from epidemiological studies that smoking is a risk factor for both cataract and AMD. There is moderate evidence for an association with sunlight and cataract but weak evidence for sunlight and AMD. The few studies that have investigated this suggest an adverse effect of biomass fuels on cataract risk. The antioxidant defence system of the lens and retina include antioxidant vitamins C and E and the carotenoids lutein and zinc, and there is mixed evidence on their associations with cataract and AMD from epidemiological studies. Most epidemiological studies have been conducted in well-nourished western populations but evidence is now emerging from other populations with different dietary patterns and antioxidant levels. Copyright 2010 S. Karger AG, Basel.
Shatri, Jeton; Bexheti, Dorentina; Bexheti, Sadi; Kabashi, Serbeze; Krasniqi, Shaip; Ahmetgjekaj, Ilir; Zhjeqi, Valbona
2017-10-15
Circulus arteriosus cerebri is the main source of blood supply to the brain; it connects the left and right hemispheres with anterior and posterior parts. Located at the interpenducular fossa at the base of the brain the circle of Willis is the most important source of collateral circulation in the presence of the disease in the carotid or vertebral artery. The purpose of the research is to study the diameter and length of arteries and provide an important source of reference on Kosovo's population. This is an observative descriptive study performed at the University Clinical Center of Kosovo. A randomised sample of 133 angiographic examinations in adult patients of both sexes who were instructed to exploration is included. The diameters and lengths measured in our study were comparable with other brain-cadaver studies especially those performed by MRA. All dimensions of the arteries are larger in male than female, except the diameter of PCoA that is larger in female (p < 0.05) and length of the ACoA (p < 0.05). Significant differences were found in diameters of arteries between the younger and the older age groups. Knowing the dimensions of the arteries of the circle of Willis has a great importance in interventional radiology as well as during anatomy lessons.
Shatri, Jeton; Bexheti, Dorentina; Bexheti, Sadi; Kabashi, Serbeze; Krasniqi, Shaip; Ahmetgjekaj, Ilir; Zhjeqi, Valbona
2017-01-01
BACKGROUND: Circulus arteriosus cerebri is the main source of blood supply to the brain; it connects the left and right hemispheres with anterior and posterior parts. Located at the interpenducular fossa at the base of the brain the circle of Willis is the most important source of collateral circulation in the presence of the disease in the carotid or vertebral artery. AIM: The purpose of the research is to study the diameter and length of arteries and provide an important source of reference on Kosovo’s population. METHODS: This is an observative descriptive study performed at the University Clinical Center of Kosovo. A randomised sample of 133 angiographic examinations in adult patients of both sexes who were instructed to exploration is included. RESULTS: The diameters and lengths measured in our study were comparable with other brain-cadaver studies especially those performed by MRA. All dimensions of the arteries are larger in male than female, except the diameter of PCoA that is larger in female (p < 0.05) and length of the ACoA (p < 0.05). Significant differences were found in diameters of arteries between the younger and the older age groups. CONCLUSION: Knowing the dimensions of the arteries of the circle of Willis has a great importance in interventional radiology as well as during anatomy lessons. PMID:29104678
Sources of health information among Chinese immigrants to the Pacific Northwest.
Woodall, Erica D; Taylor, Victoria M; Teh, Chong; Li, Lin; Acorda, Elizabeth; Tu, Shin-Ping; Yasui, Yutaka; Hislop, T Gregory
2009-01-01
Chinese immigrants to North America experience cancer-related health disparities and underutilize preventive care. Little is known about Chinese immigrants' sources of health information. A population-based survey of Chinese immigrants was conducted in Vancouver, British Columbia, Canada and Seattle, Washington. The study group included 899 individuals. Less than three fourths of the respondents reported receiving health information from health care providers, and only a minority used the Internet as a source of health information. We found significant differences between the sources of health information in Seattle and Vancouver. Health educators should consider available media outlets as well as the characteristics of a target community when planning intervention programs for Chinese immigrants.
Folate intake in a Swedish adult population: Food sources and predictive factors.
Monteagudo, Celia; Scander, Henrik; Nilsen, Bente; Yngve, Agneta
2017-01-01
Introduction : Folate plays an important role in cell metabolism, but international studies show that intake is currently below recommendations, especially among women. The study objective was to identify folate food sources by food group, gender, and age group, and to identify factors influencing folate intake, based on food consumption data for Swedish adults in the 2010-11 Riksmaten study. M ethods : The sample included a representative Swedish population aged 18-80 years ( n = 1657; 56.3% female). Food and nutrient intakes were estimated from self-reported food records during 4 consecutive days. Food consumption was categorized into 26 food groups. Stepwise regression was used to analyze food groups as folate sources for participants. Factors predicting the highest folate intake (third tertile) were determined by logistic regression analysis. Results : Vegetables and pulses represented the most important folate source for all age groups and both genders, especially in women aged 45-64 years (49.7% of total folate intake). The next folate source in importance was dairy products for the youngest group (18-30 years), bread for men, and fruit and berries for women. The likelihood of being in the highest tertile of folate intake (odds ratio = 1.69, 95% confidence interval 1.354-2.104) was higher for men. Influencing factors for folate intake in the highest tertile were low body mass index and high educational level in the men, and high educational level, vegetarian diet, organic product consumption, non-smoking, and alcohol consumption within recommendations in the women. Conclusion : This study describes the folate intake per food group of Swedish adults according to the 2010-11 Riksmaten survey, identifying vegetables and pulses as the most important source. Data obtained on factors related to folate consumption may be useful for the development of specific nutrition education programs to increase the intake of this vitamin in high-risk groups.
Folate intake in a Swedish adult population: Food sources and predictive factors
Monteagudo, Celia; Scander, Henrik; Nilsen, Bente; Yngve, Agneta
2017-01-01
ABSTRACT Introduction: Folate plays an important role in cell metabolism, but international studies show that intake is currently below recommendations, especially among women. The study objective was to identify folate food sources by food group, gender, and age group, and to identify factors influencing folate intake, based on food consumption data for Swedish adults in the 2010–11 Riksmaten study. Methods: The sample included a representative Swedish population aged 18–80 years (n = 1657; 56.3% female). Food and nutrient intakes were estimated from self-reported food records during 4 consecutive days. Food consumption was categorized into 26 food groups. Stepwise regression was used to analyze food groups as folate sources for participants. Factors predicting the highest folate intake (third tertile) were determined by logistic regression analysis. Results: Vegetables and pulses represented the most important folate source for all age groups and both genders, especially in women aged 45–64 years (49.7% of total folate intake). The next folate source in importance was dairy products for the youngest group (18–30 years), bread for men, and fruit and berries for women. The likelihood of being in the highest tertile of folate intake (odds ratio = 1.69, 95% confidence interval 1.354–2.104) was higher for men. Influencing factors for folate intake in the highest tertile were low body mass index and high educational level in the men, and high educational level, vegetarian diet, organic product consumption, non-smoking, and alcohol consumption within recommendations in the women. Conclusion: This study describes the folate intake per food group of Swedish adults according to the 2010–11 Riksmaten survey, identifying vegetables and pulses as the most important source. Data obtained on factors related to folate consumption may be useful for the development of specific nutrition education programs to increase the intake of this vitamin in high-risk groups. PMID:28659736
Reduced Variance using ADVANTG in Monte Carlo Calculations of Dose Coefficients to Stylized Phantoms
NASA Astrophysics Data System (ADS)
Hiller, Mauritius; Bellamy, Michael; Eckerman, Keith; Hertel, Nolan
2017-09-01
The estimation of dose coefficients of external radiation sources to the organs in phantoms becomes increasingly difficult for lower photon source energies. This study focus on the estimation of photon emitters around the phantom. The computer time needed to calculate a result within a certain precision can be lowered by several orders of magnitude using ADVANTG compared to a standard run. Using ADVANTG which employs the DENOVO adjoint calculation package enables the user to create a fully populated set of weight windows and source biasing instructions for an MCNP calculation.
Sources and Sinks: A Stochastic Model of Evolution in Heterogeneous Environments
NASA Astrophysics Data System (ADS)
Hermsen, Rutger; Hwa, Terence
2010-12-01
We study evolution driven by spatial heterogeneity in a stochastic model of source-sink ecologies. A sink is a habitat where mortality exceeds reproduction so that a local population persists only due to immigration from a source. Immigrants can, however, adapt to conditions in the sink by mutation. To characterize the adaptation rate, we derive expressions for the first arrival time of adapted mutants. The joint effects of migration, mutation, birth, and death result in two distinct parameter regimes. These results may pertain to the rapid evolution of drug-resistant pathogens and insects.
Varshavsky, Julia R; Morello-Frosch, Rachel; Woodruff, Tracey J; Zota, Ami R
2018-06-01
Anti-androgenic phthalates are reproductive toxicants that may have additive effects on male development. Diet is the primary exposure source for most phthalates, which contaminate the food supply through food contact materials and industrialized production. To compare dietary sources of cumulative phthalates exposure between "food at home" (e.g. food consumed from a grocery store) and "food away from home" (e.g. food consumed from fast food/restaurants and cafeterias) in the U.S. general population. We estimated cumulative phthalates exposure by calculating daily intake from metabolite concentrations in urinary spot samples for 10,253 participants (≥6 years old) using National Health and Nutrition Examination Survey (NHANES, 2005-2014) data. We constructed a biologically relevant metric of phthalates daily intake (∑androgen-disruptor, μg/kg/day) by converting phthalates into anti-androgen equivalent terms prior to their summation. Particular foods and the percent of total energy intake (TEI) consumed from multiple dining out sources were ascertained from 24-h recall surveys. Associations with ∑androgen-disruptor levels were estimated for children, adolescents, and adults using multivariable linear regression. We observed a consistent positive association between dining out and Σandrogen-disruptor levels across the study population (p-trend <0.0001). Among adolescents, high consumers of foods outside the home had 55% (95% CI: 35%, 78%) higher Σandrogen-disruptor levels compared to those who only consumed food at home. The contribution of specific dining out sources to Σandrogen-disruptor levels varied by age group. For example, cafeteria food was associated with 15% (95% CI: 4.0%, 28%) and 64% (95% CI: 40%, 92%) higher Σandrogen-disruptor levels in children and adults, respectively. Particular foods, especially sandwiches (i.e. cheeseburgers), were associated with increased Σandrogen-disruptor levels only if they were purchased away from home (p < 0.01). Dining out may be an important source of biologically relevant cumulative phthalates exposure among the U.S. Future studies should evaluate modifiable production practices that remove phthalates from the food supply in addition to the efficacy of interventions that promote eating fresh foods prepared at home. Copyright © 2018 Elsevier Ltd. All rights reserved.
Renal disease disparities in Asian and Pacific-based populations in Hawai'i.
Mau, Marjorie K.; West, Margaret; Sugihara, Jared; Kamaka, Martina; Mikami, Judy; Cheng, Shiuh-Feng
2003-01-01
The prevalence of end-stage renal disease (ESRD) in the United States is expected to double over the next 10 years. The identification of ethnic differences in the prevalence, treatment, morbidity, and mortality related to chronic kidney disease (CKD) is of great concern. Asian Americans comprise a rapidly expanding sector of the U.S. population and are reported to have ESRD growth rates that are approximately 50% higher than caucasians. Hawai'i has a large, well-established Asian and Pacific-based population that facilitates the examination of disparities in renal disease among the state's diverse ethnic groups. The prevalence of ESRD in Hawai'i has continued to rise due, in part, to high rates of diabetes, glomerulonephritis, and hypertension reported in Asian Americans and Pacific-based populations. ESRD patients in Hawai'i have a two-fold higher prevalence of glomerulonephritis, compared with the general ESRD population in the United States. Other potential sources of renal disparities-such as cultural factors, language barriers, and health access factors-among Hawaii's major ethnic groups are assessed. However, few studies have examined the relative contribution of these potential factors. Consequently, efforts to reduce and eventually eliminate renal disease disparities will require a better understanding of the major sources of health disparities, such as timely medical care, a diverse health workforce, and cultural/social barriers, that affect optimal health care practices in Asian and Pacific-based populations. PMID:14620708
Growth phenology of coast Douglas-fir seed sources planted in diverse environments.
Gould, Peter J; Harrington, Constance A; St Clair, J Bradley
2012-12-01
The timing of periodic life cycle events in plants (phenology) is an important factor determining how species and populations will react to climate change. We evaluated annual patterns of basal-area and height growth of coast Douglas-fir (Pseudotusga menziesii var. menziesii (Mirb.) Franco) seedlings from four seed sources that were planted in four diverse environments as part of the Douglas-fir Seed-Source Movement Trial. Stem diameters and heights were measured periodically during the 2010 growing season on 16 open-pollinated families at each study installation. Stem diameters were measured on a subset of trees with electronic dendrometers during the 2010 and 2011 growing seasons. Trees from the four seed sources differed in phenology metrics that described the timing of basal-area and height-growth initiation, growth cessation and growth rates. Differences in the height-growth metrics were generally larger than differences in the basal-area growth metrics and differences among installations were larger than differences among seed sources, highlighting the importance of environmental signals on growth phenology. Variations in the height- and basal-area growth metrics were correlated with different aspects of the seed-source environments: precipitation in the case of height growth and minimum temperature in the case of basal-area growth. The detailed dendrometer measurements revealed differences in growth patterns between seed sources during distinct periods in the growing season. Our results indicate that multiple aspects of growth phenology should be considered along with other traits when evaluating adaptation of populations to future climates.
2013-01-01
Background Studies suggest that immigrants have higher rates of anxiety-depression than compatriots in low-middle income countries and lower rates than populations in host high income countries. Elucidating the factors that underlie these stepwise variations in prevalence may throw new light on the pathogenesis of anxiety-depressive disorders globally. This study aimed to examine whether quantitative differences in exposure to, or the interaction between, risk factors account for these anxiety-depression prevalence differences amongst immigrant relative to source and host country populations. Methods Multistage population mental health surveys were conducted in three groups: 1) a Vietnamese-immigrant sample settled in Australia (n = 1161); 2) a Vietnamese source country sample residing in the Mekong Delta region (n = 3039); 3) an Australian-born host country sample (n = 7964). Multivariable logistic regression analyses compared risk factors between the Vietnamese-immigrant group and: 1) the Mekong Delta Vietnamese; and 2) the Australian-born group. Twelve month anxiety-depression diagnoses were the main outcome measures, derived from the Composite International Diagnostic Interview (CIDI), supplemented by an indigenously derived measure - the Phan Vietnamese Psychiatric Scale (PVPS) in both Vietnamese groups. Results The 12-month prevalence of anxiety-depression showed a stepwise increase across groups: Mekong Delta Vietnamese 4.8%; Vietnamese-immigrants 7.0%; Australian-born 10.2%. The two Vietnamese populations showed a similar risk profile with older age, exposure to potentially traumatic events (PTEs), multiple physical illnesses and substance use disorder (SUD) being associated with anxiety-depression, with the older Vietnamese-immigrants reporting greater exposure to these factors. The interaction between key risk factors differed fundamentally when comparing Vietnamese-immigrant and Australian-born samples. Age emerged as the major discriminator, with young Vietnamese-immigrants exhibiting particularly low rates of anxiety-depression. Conclusions The findings reported here suggest that core risk factors for anxiety-depression may be universal, but their patterning and interaction may differ according to country-of-origin. The study also highlights the importance of including both standard international and culturally-specific measures to index cross-cultural manifestations of common mental disorders. PMID:24294940
Spontaneous pregnancy loss in humans and exposure to arsenic in drinking water.
Bloom, Michael S; Fitzgerald, Edward F; Kim, Keewan; Neamtiu, Iulia; Gurzau, Eugen S
2010-11-01
Maternal exposure to high concentrations of inorganic arsenic (iAs) in naturally contaminated drinking groundwater sources has been associated with an increased risk for the spontaneous loss of clinically recognized pregnancies in several epidemiologic studies. Whereas a large worldwide population depends on drinking groundwater sources with high levels of iAs contamination, in quantities exceeding 10 parts per billion (ppb), an even larger population is likely to be exposed to mild-moderate drinking groundwater iAs contamination, in quantities <10ppb. Only a single epidemiologic study to date has considered spontaneous pregnancy loss in association with consumption of drinking water with mild-moderate iAs contamination; the vast majority of published studies of spontaneous loss addressed populations with substantial exposure. The aim of this review is to evaluate the published literature to assess the plausibility for a causal association between exposure to iAs-contaminated drinking water and the spontaneous loss of clinically recognized pregnancy. In spite of numerous methodologic limitations resulting from circumstance or design, a consistent pattern of increased risk for loss is suggested by the epidemiologic literature. Moreover, these study results are corroborated by a large number of experimental studies, albeit usually conducted at concentrations exceeding that to which humans are exposed via contaminated drinking water. In this review, we discuss sources of human iAs exposure, highlight several experimental studies pertinent to a possible causal link between iAs and spontaneous pregnancy loss in humans, and provide a critical review of published epidemiologic studies of pregnancy loss and drinking water iAs exposures, and their limitations. Based on a review of the published literature, we recommend the future conduct of a two-stage comprehensive prospective study of low-moderate iAs drinking water exposure and spontaneous pregnancy loss. Copyright © 2010 Elsevier GmbH. All rights reserved.
Knowledge, attitude and practices of people towards voluntary blood donation in Uttarakhand.
Agrawal, Amit; Tiwari, Aseem K; Ahuja, Alok; Kalra, Rakesh
2013-01-01
Blood transfusions form a crucial and irreplaceable part in the medical management of many diseases. The collection of blood from voluntary, non-remunerated blood donors from low risk populations is an important measure for ensuring the availability and safety of blood transfusion. In a state like Uttarakhand which is visited by lakhs of visitors during pilgrimage season and where natural calamities and accidents are very common, the availability of blood is of utmost importance. To find out knowledge, attitude and practices of people towards voluntary blood donation to comprehend the situation and find ways to enhance voluntary blood donation in the state of Uttarakhand. Multi stage methodology was designed to target population including general population, influencers (doctors) and supporting organizations (camp organizers, State AIDS Control Society Officials) who were subjected to in-depth interview using pre-structured questionnaires to assess knowledge/awareness about voluntary blood donation, factors preventing and source of knowledge about voluntary blood donation. The sample population consisted of mostly men (67%) in the age-group of 26-35 years. Requirement of blood and the measures to promote voluntary blood donation have a direct relationship with the total population and literacy level of the population. Awareness about blood donation, source of knowledge about blood donation, reasons for not donating blood are particularly stressed. With increase in educational level, the awareness level was also found to increase. While among illiterates 81 percent of the respondents knew about blood donation, among the post graduates the same ratio was found to be almost cent-percent. Among various reasons cited for not donating blood, lack of awareness being the most common reason. People gathered information about blood donation from several different sources with electronic media being the most prominent. This study illustrates how increasing awareness and marketing 'Voluntary blood donation' can enhance adequacy of blood needs of a state or for that matter the entire country. This study also underlines how different media, especially electronic media, can be used to propagate altruistic blood donation.
Knowledge, attitude and practices of people towards voluntary blood donation in Uttarakhand
Agrawal, Amit; Tiwari, Aseem K.; Ahuja, Alok; Kalra, Rakesh
2013-01-01
Introduction: Blood transfusions form a crucial and irreplaceable part in the medical management of many diseases. The collection of blood from voluntary, non-remunerated blood donors from low risk populations is an important measure for ensuring the availability and safety of blood transfusion. In a state like Uttarakhand which is visited by lakhs of visitors during pilgrimage season and where natural calamities and accidents are very common, the availability of blood is of utmost importance. Aim: To find out knowledge, attitude and practices of people towards voluntary blood donation to comprehend the situation and find ways to enhance voluntary blood donation in the state of Uttarakhand. Materials and Methods: Multi stage methodology was designed to target population including general population, influencers (doctors) and supporting organizations (camp organizers, State AIDS Control Society Officials) who were subjected to in-depth interview using pre-structured questionnaires to assess knowledge/awareness about voluntary blood donation, factors preventing and source of knowledge about voluntary blood donation. Result: The sample population consisted of mostly men (67%) in the age-group of 26-35 years. Requirement of blood and the measures to promote voluntary blood donation have a direct relationship with the total population and literacy level of the population. Awareness about blood donation, source of knowledge about blood donation, reasons for not donating blood are particularly stressed. With increase in educational level, the awareness level was also found to increase. While among illiterates 81 percent of the respondents knew about blood donation, among the post graduates the same ratio was found to be almost cent-percent. Among various reasons cited for not donating blood, lack of awareness being the most common reason. People gathered information about blood donation from several different sources with electronic media being the most prominent. Conclusion: This study illustrates how increasing awareness and marketing ‘Voluntary blood donation’ can enhance adequacy of blood needs of a state or for that matter the entire country. This study also underlines how different media, especially electronic media, can be used to propagate altruistic blood donation. PMID:23559768
Mortality sensitivity in life-stage simulation analysis: A case study of southern sea otters
Gerber, L.R.; Tinker, M.T.; Doak, D.F.; Estes, J.A.; Jessup, David A.
2004-01-01
Currently, there are no generally recognized approaches for linking detailed mortality and pathology data to population-level analyses of extinction risk. We used a combination of analytical and simulation-based analyses to examine 20 years of age- and sex-specific mortality data for southern sea otters (Enhydra lutris), and we applied results to project the efficacy of alternative conservation strategies. Population recovery of the southern sea otter has been slow (rate of population increase ?? = 1.05) compared to other recovering populations (?? = 1.17-1.20), and the population declined (?? = 0.975) between 1995 and 1999. Age-based Leslie matrices were developed to explore explanations for the slow recovery and recent decline in the southern sea other population. An elasticity analysis was performed to predict effects of proportional changes in stage-specific reproductive or survival rates on the rate of population increase. A life-stage simulation analysis (LSA) was developed to evaluate the impact of changing age- and cause-specific mortality rates on ??. The information used to develop these models was derived from death assemblage, pathology, and live population census data to examine the sensitivity of sea otter population growth to different sources of mortality (e.g., disease and starvation, direct human take [fisheries, gun shot, boat strike, oil pollution], mating trauma and intraspecific aggression, shark bites, and unknown). We used resampling simulations to generate random combinations of vital rates for a large number of matrix replicates and drew on these to estimate potential effects of mortality sources on population growth (??). Our analyses suggest management actions that are likely and unlikely to promote recovery of the southern sea otter and more broadly indicate a methodology to better utilize cause-of-death data in conservation decision-making.
Serwaa-Bonsu, Adwoa; Herbst, Abraham J; Reniers, Georges; Ijaa, Wilfred; Clark, Benjamin; Kabudula, Chodziwadziwa; Sankoh, Osman
2010-02-24
In developing countries, Health and Demographic Surveillance Systems (HDSSs) provide a framework for tracking demographic and health dynamics over time in a defined geographical area. Many HDSSs co-exist with facility-based data sources in the form of Health Management Information Systems (HMIS). Integrating both data sources through reliable record linkage could provide both numerator and denominator populations to estimate disease prevalence and incidence rates in the population and enable determination of accurate health service coverage. To measure the acceptability and performance of fingerprint biometrics to identify individuals in demographic surveillance populations and those attending health care facilities serving the surveillance populations. Two HDSS sites used fingerprint biometrics for patient and/or surveillance population participant identification. The proportion of individuals for whom a fingerprint could be successfully enrolled were characterised in terms of age and sex. Adult (18-65 years) fingerprint enrolment rates varied between 94.1% (95% CI 93.6-94.5) for facility-based fingerprint data collection at the Africa Centre site to 96.7% (95% CI 95.9-97.6) for population-based fingerprint data collection at the Agincourt site. Fingerprint enrolment rates in children under 1 year old (Africa Centre site) were only 55.1% (95% CI 52.7-57.4). By age 5, child fingerprint enrolment rates were comparable to those of adults. This work demonstrates the feasibility of fingerprint-based individual identification for population-based research in developing countries. Record linkage between demographic surveillance population databases and health care facility data based on biometric identification systems would allow for a more comprehensive evaluation of population health, including the ability to study health service utilisation from a population perspective, rather than the more restrictive health service perspective.
Sources of hydrocarbons in urban road dust: Identification, quantification and prediction.
Mummullage, Sandya; Egodawatta, Prasanna; Ayoko, Godwin A; Goonetilleke, Ashantha
2016-09-01
Among urban stormwater pollutants, hydrocarbons are a significant environmental concern due to their toxicity and relatively stable chemical structure. This study focused on the identification of hydrocarbon contributing sources to urban road dust and approaches for the quantification of pollutant loads to enhance the design of source control measures. The study confirmed the validity of the use of mathematical techniques of principal component analysis (PCA) and hierarchical cluster analysis (HCA) for source identification and principal component analysis/absolute principal component scores (PCA/APCS) receptor model for pollutant load quantification. Study outcomes identified non-combusted lubrication oils, non-combusted diesel fuels and tyre and asphalt wear as the three most critical urban hydrocarbon sources. The site specific variabilities of contributions from sources were replicated using three mathematical models. The models employed predictor variables of daily traffic volume (DTV), road surface texture depth (TD), slope of the road section (SLP), effective population (EPOP) and effective impervious fraction (EIF), which can be considered as the five governing parameters of pollutant generation, deposition and redistribution. Models were developed such that they can be applicable in determining hydrocarbon contributions from urban sites enabling effective design of source control measures. Copyright © 2016 Elsevier Ltd. All rights reserved.
Tabacchi, Garden; Costantino, Claudio; Cracchiolo, Manuela; Ferro, Antonio; Marchese, Valentina; Napoli, Giuseppe; Palmeri, Sara; Raia, Daniele; Restivo, Vincenzo; Siddu, Andrea; Vitale, Francesco; Casuccio, Alessandra
2017-02-01
Vaccine knowledge of the general population is shaped by different information sources and strongly influences vaccination attitudes and uptake. The CCM-Italian Ministry of Health ESCULAPIO project attempted to identify the role of such information sources, in order to address adequate strategies to improve information on vaccines and vaccine preventable diseases. In the present study, data on 632 adults from Southern Italy regarding information sources were collected, and their perceived and actual knowledge on vaccinations were compared and analyzed in relation to socio-demographic characteristics and information sources. The main reported reference sources were general practitioners (GPs) (42.5%) and pediatricians (33.1%), followed by mass media (24.1%) and the Internet (17.6%). A total of 45.4% reported they believed to be informed (45.4%), while those estimated to be truly informed were 43.8%. However, as showed in the multivariate logistic regression, people having the perception to be correctly informed ascribed their good knowledge to their profession in the health sector (Adj OR 2.28, CI 1.09-4.77, p < 0.05) and to friends/relatives/colleagues (AdjOR 6.25, CI 2.38-16.44, p < 0.001), while the non-informed population thought the responsibility had to be attributed to mass media (AdjOR 0.45, CI 0.22-0.92, p < 0.05). Those showing the real correct information, instead, were younger (AdjOR 1.64, CI 1.04-2.59, p < 0.05), and their main reference sources were pediatricians (AdjOR 1.63, CI 1.11-2.39, p < 0.05) and scientific magazines (Adj OR 3.39, CI 1.51-7.59, p < 0.01). Only 6% knew the "VaccinarSì" portal, developed to counter the widespred antivaccine websites in Italy. The post-survey significant increase of connections to "VaccinarSi" could be ascribed to the counselling performed during questionnaire administration. Strategies to improve information about vaccination should be addressed to fortifying healthcare workers knowledge in order to make them public health opinion leaders. General population should be provided with correct indications on trustworthy websites on vaccines to contrast false information supplied by anti-vaccinists on their own websites or social networks pages and on the mass media.
Costantino, Claudio; Cracchiolo, Manuela; Ferro, Antonio; Marchese, Valentina; Napoli, Giuseppe; Palmeri, Sara; Raia, Daniele; Restivo, Vincenzo; Siddu, Andrea; Vitale, Francesco; Casuccio, Alessandra
2017-01-01
ABSTRACT Vaccine knowledge of the general population is shaped by different information sources and strongly influences vaccination attitudes and uptake. The CCM-Italian Ministry of Health ESCULAPIO project attempted to identify the role of such information sources, in order to address adequate strategies to improve information on vaccines and vaccine preventable diseases. In the present study, data on 632 adults from Southern Italy regarding information sources were collected, and their perceived and actual knowledge on vaccinations were compared and analyzed in relation to socio-demographic characteristics and information sources. The main reported reference sources were general practitioners (GPs) (42.5%) and pediatricians (33.1%), followed by mass media (24.1%) and the Internet (17.6%). A total of 45.4% reported they believed to be informed (45.4%), while those estimated to be truly informed were 43.8%. However, as showed in the multivariate logistic regression, people having the perception to be correctly informed ascribed their good knowledge to their profession in the health sector (Adj OR 2.28, CI 1.09–4.77, p < 0.05) and to friends/relatives/colleagues (AdjOR 6.25, CI 2.38–16.44, p < 0.001), while the non-informed population thought the responsibility had to be attributed to mass media (AdjOR 0.45, CI 0.22–0.92, p < 0.05). Those showing the real correct information, instead, were younger (AdjOR 1.64, CI 1.04–2.59, p < 0.05), and their main reference sources were pediatricians (AdjOR 1.63, CI 1.11–2.39, p < 0.05) and scientific magazines (Adj OR 3.39, CI 1.51–7.59, p < 0.01). Only 6% knew the “VaccinarSì” portal, developed to counter the widespred antivaccine websites in Italy. The post-survey significant increase of connections to “VaccinarSi” could be ascribed to the counselling performed during questionnaire administration. Strategies to improve information about vaccination should be addressed to fortifying healthcare workers knowledge in order to make them public health opinion leaders. General population should be provided with correct indications on trustworthy websites on vaccines to contrast false information supplied by anti-vaccinists on their own websites or social networks pages and on the mass media. PMID:28032814
NASA Astrophysics Data System (ADS)
Mubareka, Sarah Betoul
Remote sensing and security, terms which are not usually associated, have found a common platform this decade with the conjuring of the GMOSS network (Global Monitoring for Security and Stability), whose mandate is to discover new applications for satellite-derived imagery to security issues. This study focuses on human security, concentrating on the characterisation of vulnerable areas to conflict. A time-series of satellite imagery taken from Landsat sensors from 1987 to 2001 and the SRTM mission imagery are used for this purpose over a site in northern Iraq. Human security issues include the exposure to any type of hazard. The region of study is first characterised in order to understand which hazards are and were present in the past for the region of study. The principal hazard for the region of study is armed conflict and the relative field data was analysed to determine the links between geographical indicators and vulnerable areas. This is done through historical research and the study of open-sourced information about disease outbreaks; the movements of refugees and the internally displaced; and humanitarian aid and security issues. These open sources offer information which are not always consistent, objective, or normalized and are therefore difficult to quantify. A method for the rapid mapping and graphing and subsequent analysis of the situation in a region where limited information is available is developed. This information is coupled with population numbers to create a "risk map": A disaggregated matrix of areas most at risk during conflict situations. The results show that describing the risk factor for a population to the hazard conflict depends on three complex indicators: Population density, remoteness and economic diversity. Each of these complex indicators is then derived from Landsat and SRTM imagery and a satellite-driven model is formulated. This model based on satellite imagery is applied to the study site for a temporal study. The output are three 90 m x 90 m resolution grids which describe, at a pixel level, the risk level within the region for each of the dates studies, and the changes which occur in northern Iraq as the result of the Anfal Campaigns. Results show that satellite imagery, with a minimum of processing, can yield indicators for characterising risk in a region. Although by no means a replacement for field data, this technological source, in the absence of local knowledge, can provide users with a starting point in understanding which areas are most at risk within a region. If this data is coupled with open sourced information such as political and cultural discrimination, economy and agricultural practices, a fairly accurate risk map can be generated in the absence of field data. Keywords. SRTM, Landsat, risk indicators, Iraq, conflict, population vulnerability, segmentation, land-use, fuzzy-classification, atmospheric corrections.
Marr, Melissa M; Brace, Selina; Schreve, Danielle C; Barnes, Ian
2018-02-09
Establishing true phylogenetic relationships between populations is a critical consideration when sourcing individuals for translocation. This presents huge difficulties with threatened and endangered species that have become extirpated from large areas of their former range. We utilise ancient DNA (aDNA) to reconstruct the phylogenetic relationships of a keystone species which has become extinct in Britain, the Eurasian beaver Castor fiber. We sequenced seventeen 492 bp partial tRNAPro and control region sequences from Late Pleistocene and Holocene age beavers and included these in network, demographic and genealogy analyses. The mode of postglacial population expansion from refugia was investigated by employing tests of neutrality and a pairwise mismatch distribution analysis. We found evidence of a pre-Late Glacial Maximum ancestor for the Western C. fiber clade which experienced a rapid demographic expansion during the terminal Pleistocene to early Holocene period. Ancient British beavers were found to originate from the Western phylogroup but showed no phylogenetic affinity to any one modern relict population over another. Instead, we find that they formed part of a large, continuous, pan-Western European clade that harbored little internal substructure. Our study highlights the utility of aDNA in reconstructing population histories of extirpated species which has real-world implications for conservation planning.
Efficient Moment-Based Inference of Admixture Parameters and Sources of Gene Flow
Levin, Alex; Reich, David; Patterson, Nick; Berger, Bonnie
2013-01-01
The recent explosion in available genetic data has led to significant advances in understanding the demographic histories of and relationships among human populations. It is still a challenge, however, to infer reliable parameter values for complicated models involving many populations. Here, we present MixMapper, an efficient, interactive method for constructing phylogenetic trees including admixture events using single nucleotide polymorphism (SNP) genotype data. MixMapper implements a novel two-phase approach to admixture inference using moment statistics, first building an unadmixed scaffold tree and then adding admixed populations by solving systems of equations that express allele frequency divergences in terms of mixture parameters. Importantly, all features of the model, including topology, sources of gene flow, branch lengths, and mixture proportions, are optimized automatically from the data and include estimates of statistical uncertainty. MixMapper also uses a new method to express branch lengths in easily interpretable drift units. We apply MixMapper to recently published data for Human Genome Diversity Cell Line Panel individuals genotyped on a SNP array designed especially for use in population genetics studies, obtaining confident results for 30 populations, 20 of them admixed. Notably, we confirm a signal of ancient admixture in European populations—including previously undetected admixture in Sardinians and Basques—involving a proportion of 20–40% ancient northern Eurasian ancestry. PMID:23709261
NASA Astrophysics Data System (ADS)
Li, Xiang-Yong; Chu, Dong; Yin, Yan-Qiong; Zhao, Xue-Qing; Chen, Ai-Dong; Khay, Sathya; Douangboupha, Bounneuang; Kyaw, Mu Mu; Kongchuensin, Manita; Ngo, Vien Vinh; Nguyen, Chung Huy
2016-12-01
The white-backed planthopper, Sogatella furcifera (Horváth) (Hemiptera: Delphacidae), is a serious pest of rice in Asia. However, little is known regarding the migration of this pest insect from the Greater Mekong Subregion (GMS) including Cambodia, Laos, Myanmar (Burma), Thailand, and Vietnam, into China’s Yunnan Province. To determine the migration patterns of S. furcifera in the GMS and putative secondary immigration inside China’s Yunnan Province, we investigated the population genetic diversity, genetic structure, and gene flow of 42 S. furcifera populations across the six countries in the GMS by intensive sampling using mitochondrial genes. Our study revealed the potential emigration of S. furcifera from the GMS consists primarily of three major sources: 1) the S. furcifera from Laos and Vietnam migrate into south and southeast Yunnan, where they proceed to further migrate into northeast and central Yunnan; 2) the S. furcifera from Myanmar migrate into west Yunnan, and/or central Yunnan, and/or northeast Yunnan; 3) the S. furcifera from Cambodia migrate into southwest Yunnan, where the populations can migrate further into central Yunnan. The new data will not only be helpful in predicting population dynamics of the planthopper, but will also aid in regional control programs for this economically important pest insect.
Residential Mobility and Lung Cancer Risk: Data-Driven Exploration Using Internet Sources
DOE Office of Scientific and Technical Information (OSTI.GOV)
Yoon, Hong-Jun; Tourassi, Georgia; Xu, Songhua
2015-01-01
Frequent relocation has been linked to health decline, particularly with respect to emotional and psychological wellbeing. In this paper we investigate whether there is an association between frequent relocation and lung cancer risk. For the initial investigation we leverage two online data sources to collect cancer and control subjects using web crawling and tailored text mining. The two data sources share different strengths and weaknesses in terms of the amount of detail, population representation, and sample size. One data source includes online obituaries. The second data source includes augmented LinkedIn profiles. For each data source, the subjects spatiotemporal history ismore » reconstructed from the available information provided in the obituaries and from the education and work experience provided in the LinkedIn profiles. The study shows that lung cancer subjects have higher mobility frequency than the control group. This trend is consistent for both data sources.« less
Polycyclic Aromatic Hydrocarbons and Esophageal Squamous Cell Carcinoma-A Review
Roshandel, Gholamreza; Semnani, Shahryar; Malekzadeh, Reza; Dawsey, Sanford M.
2018-01-01
Esophageal cancer (EC) is the 8th most common cancer and the 6th most frequent cause of cancer mortality worldwide. Esophageal squamous cell carcinoma (ESCC) is the most common type of EC. Exposure to polycyclic aromatic hydrocarbons (PAHs) has been suggested as a risk factor for developing ESCC. In this paper we will review different aspects of the relationship between PAH exposure and ESCC. PAHs are a group of compounds that are formed by incomplete combustion of organic matter. Studies in humans have shown an association between PAH exposure and development of ESCC in many populations. The results of a recent case-control study in a high risk population in northeastern Iran showed a dramatic dose-response relationship between PAH content in non-tumor esophageal tissue (the target tissue for esophageal carcinogenesis) and ESCC case status, consistent with a causal role for PAH exposure in the pathogenesis of ESCC. Identifying the main sources of exposure to PAHs may be the first and most important step in designing appropriate PAH-reduction interventions for controlling ESCC, especially in high risk areas. Coal smoke and drinking mate have been suggested as important modifiable sources of PAH exposure in China and Brazil, respectively. But the primary source of exposure to PAHs in other high risk areas for ESCC, such as northeastern Iran, has not yet been identified. Thus, environmental studies to determining important sources of PAH exposure should be considered as a high priority in future research projects in these areas. PMID:23102250
Red nuggets grow inside-out: evidence from gravitational lensing
DOE Office of Scientific and Technical Information (OSTI.GOV)
Oldham, Lindsay; Auger, Matthew W.; Fassnacht, Christopher D.
Here, we present a new sample of strong gravitational lens systems where both the foreground lenses and background sources are early-type galaxies. Using imaging from Hubble Space Telescope (HST)/Advanced Camera for Studies (ACS) and Keck/NIRC2, we model the surface brightness distributions and show that the sources form a distinct population of massive, compact galaxies at redshifts 0.4 ≲ z ≲ 0.7, lying systematically below the size–mass relation of the global elliptical galaxy population at those redshifts. These may therefore represent relics of high-redshift red nuggets or their partly evolved descendants. We exploit the magnifying effect of lensing to investigate themore » structural properties, stellar masses and stellar populations of these objects with a view to understanding their evolution. We model these objects parametrically and find that they generally require two Sérsic components to properly describe their light profiles, with one more spheroidal component alongside a more envelope-like component, which is slightly more extended though still compact. This is consistent with the hypothesis of the inside-out growth of these objects via minor mergers. Lastly, we also find that the sources can be characterized by red-to-blue colour gradients as a function of radius which are stronger at low redshift – indicative of ongoing accretion – but that their environments generally appear consistent with that of the general elliptical galaxy population, contrary to recent suggestions that these objects are pre-dominantly associated with clusters.« less
Fonseca, Dina M; Unlu, Isik; Crepeau, Taryn; Farajollahi, Ary; Healy, Sean P; Bartlett-Healy, Kristen; Strickman, Daniel; Gaugler, Randy; Hamilton, George; Kline, Daniel; Clark, Gary G
2013-12-01
Aedes (Stegomyia) albopictus (Skuse) is an important disease vector and biting nuisance. During the 2009 active season, six ∼1000-parcel sites were studied, three in urban and three in suburban areas of New Jersey, United States, to examine the efficacy of standard integrated urban mosquito control strategies applied area wide. Active source reduction, larviciding, adulticiding and public education (source reduction through education) were implemented in one site in each county, an education-only approach was developed in a second site and a third site was used as an untreated experimental control. Populations were surveyed weekly with BG-Sentinel traps and ovitraps. A substantial reduction in Ae. albopictus populations was achieved in urban sites, but only modest reductions in suburban sites. Education alone achieved significant reductions in urban adult Ae. albopictus. Egg catches echoed adult catches only in suburban sites. There are significant socioeconomic and climatic differences between urban and suburban sites that impact upon Ae. albopictus populations and the efficacy of the control methods tested. An integrated pest management approach can affect abundances, but labor-intensive, costly source reduction was not enough to maintain Ae. albopictus counts below a nuisance threshold. Nighttime adult population suppression using truck-mounted adulticides can be effective. Area-wide cost-effective strategies are necessary. Published 2013. This article is a U.S. Government work and is in the public domain in the USA.
Red nuggets grow inside-out: evidence from gravitational lensing
Oldham, Lindsay; Auger, Matthew W.; Fassnacht, Christopher D.; ...
2016-11-03
Here, we present a new sample of strong gravitational lens systems where both the foreground lenses and background sources are early-type galaxies. Using imaging from Hubble Space Telescope (HST)/Advanced Camera for Studies (ACS) and Keck/NIRC2, we model the surface brightness distributions and show that the sources form a distinct population of massive, compact galaxies at redshifts 0.4 ≲ z ≲ 0.7, lying systematically below the size–mass relation of the global elliptical galaxy population at those redshifts. These may therefore represent relics of high-redshift red nuggets or their partly evolved descendants. We exploit the magnifying effect of lensing to investigate themore » structural properties, stellar masses and stellar populations of these objects with a view to understanding their evolution. We model these objects parametrically and find that they generally require two Sérsic components to properly describe their light profiles, with one more spheroidal component alongside a more envelope-like component, which is slightly more extended though still compact. This is consistent with the hypothesis of the inside-out growth of these objects via minor mergers. Lastly, we also find that the sources can be characterized by red-to-blue colour gradients as a function of radius which are stronger at low redshift – indicative of ongoing accretion – but that their environments generally appear consistent with that of the general elliptical galaxy population, contrary to recent suggestions that these objects are pre-dominantly associated with clusters.« less
Simon, Andrea; Britton, Robert; Gozlan, Rodolphe; van Oosterhout, Cock; Volckaert, Filip A. M.; Hänfling, Bernd
2011-01-01
The Asian cyprinid fish, the topmouth gudgeon (Pseudorasbora parva), was introduced into Europe in the 1960s. A highly invasive freshwater fish, it is currently found in at least 32 countries outside its native range. Here we analyse a 700 base pair fragment of the mitochondrial cytochrome b gene to examine different models of colonisation and spread within the invasive range, and to investigate the factors that may have contributed to their invasion success. Haplotype and nucleotide diversity of the introduced populations from continental Europe was higher than that of the native populations, although two recently introduced populations from the British Isles showed low levels of variability. Based on coalescent theory, all introduced and some native populations showed a relative excess of nucleotide diversity compared to haplotype diversity. This suggests that these populations are not in mutation-drift equilibrium, but rather that the relative inflated level of nucleotide diversity is consistent with recent admixture. This study elucidates the colonisation patterns of P. parva in Europe and provides an evolutionary framework of their invasion. It supports the hypothesis that their European colonisation was initiated by their introduction to a single location or small geographic area with subsequent complex pattern of spread including both long distance and stepping-stone dispersal. Furthermore, it was preceded by, or associated with, the admixture of genetically diverse source populations that may have augmented its invasive-potential. PMID:21674031
Exploring the Hard and Soft X-ray Emission of Magnetic Cataclysmic Variables
NASA Astrophysics Data System (ADS)
de Martino, D.; Anzolin, G.; Bonnet-Bidaud, J.-M.; Falanga, M.; Matt, G.; Mouchet, M.; Mukai, K.; Masetti, N.
2009-05-01
A non-negligible fraction of galactic hard (>20 keV) X-ray sources were identified as CVs of the magnetic Intermediate Polar type in INTEGRAL, SWIFT and RXTE surveys, that suggests a still hidden but potentially important population of faint hard X-ray sources. Simbol-X has the unique potential to simultaneously characterize their variable and complex soft and hard X-ray emission thus allowing to understand their putative role in galactic populations of X-ray sources.
Zhao, Yang; Monahan, Frank J; McNulty, Breige A; Gibney, Mike J; Gibney, Eileen R
2014-11-14
Vitamin E is believed to play a preventive role in diseases associated with oxidative stress. The aims of the present study were to quantify vitamin E intake levels and plasma concentrations and to assess dietary vitamin E adequacy in Irish adults. Intake data from the National Adult Nutrition Survey were used; plasma samples were obtained from a representative cohort of survey participants. Plasma α- and γ-tocopherol concentrations were measured by HPLC. The main sources of vitamin E in the diet were 'butter, spreadable fats and oils' and 'vegetables and vegetable dishes'. When vitamin E intake from supplements was taken into account, supplements were found to be the main contributor, making a contribution of 29·2 % to vitamin E intake in the total population. Supplement consumers had significantly higher plasma α-tocopherol concentrations and lower plasma γ-tocopherol concentrations when compared with non-consumers. Consumers of 'vitamin E' supplements had significantly higher vitamin E intake levels and plasma α-tocopherol concentrations compared with consumers of other types of supplements, such as multivitamin and fish oil. Comparison with the Institute of Medicine Estimated Average Requirement of 12 mg/d indicated that when vitamin E intake from food and supplement sources was taken into account, 100 % of the study participants achieved the recommended intake levels. When vitamin E intake from food sources was taken into account, only 68·4 % of the females were found to achieve the recommended intake levels compared with 99·2 % of the males. The results of the present study show that dietary vitamin E intake has a significant effect on plasma α- and γ-tocopherol concentrations. Furthermore, they show that the consumption of supplements is a major contributor to overall intake and has a significant effect on plasma vitamin E concentrations in the Irish population.
Ruiz, Enma; Varela-Moreiras, Gregorio
2017-10-15
The WHO published in 2015 its recommendations for added sugars intake: < 10% of the total energy (TE) intake in both adults and children. No updated information is available in Spain. To examine total sugar intake, mainly focused on added, and food and beverage sources. To analize fulfillment with WHO recommendations. The ANIBES Study of a representative sample of the Spanish population (9-75 yr) was used. Food and beverage records were obtained by a three-day dietary record by using a tablet device. The median total sugar intake was 17% Total TE: 7.3% for added, and 9.6% for the intrinsic sugar intake. Differences were observed for added sugar which was much higher in children and adolescents. For the intrinsic sugar, however, a higher contribution to TE was observed in the elderly. A 58.2% of children fullfill WHO recommndations (< 10% TE), lower for the adolescents (52.6%),and higher for adults (76.7%) and the elderly (89,8%). The mayor sources of total sugar were milk and dairy products (23.2%), non-alcoholic beverages (18.6%), fruits (16.8%) and sugars and sweets (15.1%) and grains (12.0%). The major sources of intrinsic sugars were fruits (31.8%), milks (19.6%), juices and nectars (11.1%), vegetables (9.89%), yogurt and fermented milk (7.18%), low-alcohol-content beverages (4.94%), bread (2.91%), and sugar soft drinks (2.24%). As for free sugars, sources were sugars and sweets (34.1%), non-alcoholic beverages (30.8%, mainly as sugar soft drinks, 25.5%) and grains (19.1%, principally as bakery and pastry, 15.2%). The present study demonstrates that only a moderate percentage of the Spanish population adhered to the present recommendations for total and added sugar intake, and urgent efforts are needed to improve diet quality in the youngest populations.
Moderate pressure plasma source of nonthermal electrons
NASA Astrophysics Data System (ADS)
Gershman, S.; Raitses, Y.
2018-06-01
Plasma sources of electrons offer control of gas and surface chemistry without the need for complex vacuum systems. The plasma electron source presented here is based on a cold cathode glow discharge (GD) operating in a dc steady state mode in a moderate pressure range of 2–10 torr. Ion-induced secondary electron emission is the source of electrons accelerated to high energies in the cathode sheath potential. The source geometry is a key to the availability and the extraction of the nonthermal portion of the electron population. The source consists of a flat and a cylindrical electrode, 1 mm apart. Our estimates show that the length of the cathode sheath in the plasma source is commensurate (~0.5–1 mm) with the inter-electrode distance so the GD operates in an obstructed regime without a positive column. Estimations of the electron energy relaxation confirm the non-local nature of this GD, hence the nonthermal portion of the electron population is available for extraction outside of the source. The use of a cylindrical anode presents a simple and promising method of extracting the high energy portion of the electron population. Langmuir probe measurements and optical emission spectroscopy confirm the presence of electrons with energies ~15 eV outside of the source. These electrons become available for surface modification and radical production outside of the source. The extraction of the electrons of specific energies by varying the anode geometry opens exciting opportunities for future exploration.
Propagating Neural Source Revealed by Doppler Shift of Population Spiking Frequency
Zhang, Mingming; Shivacharan, Rajat S.; Chiang, Chia-Chu; Gonzalez-Reyes, Luis E.
2016-01-01
Electrical activity in the brain during normal and abnormal function is associated with propagating waves of various speeds and directions. It is unclear how both fast and slow traveling waves with sometime opposite directions can coexist in the same neural tissue. By recording population spikes simultaneously throughout the unfolded rodent hippocampus with a penetrating microelectrode array, we have shown that fast and slow waves are causally related, so a slowly moving neural source generates fast-propagating waves at ∼0.12 m/s. The source of the fast population spikes is limited in space and moving at ∼0.016 m/s based on both direct and Doppler measurements among 36 different spiking trains among eight different hippocampi. The fact that the source is itself moving can account for the surprising direction reversal of the wave. Therefore, these results indicate that a small neural focus can move and that this phenomenon could explain the apparent wave reflection at tissue edges or multiple foci observed at different locations in neural tissue. SIGNIFICANCE STATEMENT The use of novel techniques with an unfolded hippocampus and penetrating microelectrode array to record and analyze neural activity has revealed the existence of a source of neural signals that propagates throughout the hippocampus. The source itself is electrically silent, but its location can be inferred by building isochrone maps of population spikes that the source generates. The movement of the source can also be tracked by observing the Doppler frequency shift of these spikes. These results have general implications for how neural signals are generated and propagated in the hippocampus; moreover, they have important implications for the understanding of seizure generation and foci localization. PMID:27013678
Possible ancestral structure in human populations.
Plagnol, Vincent; Wall, Jeffrey D
2006-07-01
Determining the evolutionary relationships between fossil hominid groups such as Neanderthals and modern humans has been a question of enduring interest in human evolutionary genetics. Here we present a new method for addressing whether archaic human groups contributed to the modern gene pool (called ancient admixture), using the patterns of variation in contemporary human populations. Our method improves on previous work by explicitly accounting for recent population history before performing the analyses. Using sequence data from the Environmental Genome Project, we find strong evidence for ancient admixture in both a European and a West African population (p approximately 10(-7)), with contributions to the modern gene pool of at least 5%. While Neanderthals form an obvious archaic source population candidate in Europe, there is not yet a clear source population candidate in West Africa.
Anthropometric measurements in Iranian men.
Gharehdaghi, Jaber; Baazm, Maryam; Ghadipasha, Masoud; Solhi, Sadra; Toutounchian, Farhoud
2018-01-01
There is inevitable need for data regarding anthropometric measurements of each community's population. These anthropometric data have various applications, including health assessment, industrial designing, plastic & orthopedic surgery, nutritional studies, anatomical studies and forensic medicine investigations. Anthropometric parameters vary from race to race throughout the world, hence providing an anthropometric profile model of residents of different geographic regions seems to be necessary. To our knowledge, there is no report of bone parameters of the Iranian population. The present study was carried out to provide data on anthropomorphic bone parameters of the Iranian population, as a basis for future relevant studies. We calculated most of the known anthropometric parameters including skull, mandible, clavicle, scapula, humerus, radius, ulna, sacrum, hip, femur, tibia and fibula of 225 male corpses during a period of 2 years (2014-2016). Data expression was done as mean ± standard deviation. The results consist the first documented report on anthropometric bone measurement profile of Iranian male population, that can be considered a valuable source of data for future research on Iranian population in this regard. Copyright © 2017 Elsevier Ltd and Faculty of Forensic and Legal Medicine. All rights reserved.
George-Nascimento, Mario; Oliva, Marcelo
2015-01-01
Research using parasites in fish population studies in the South Eastern Pacific (SEP) is summarized. There are 27 such studies (snapshots mainly) in single host species sampled at different geographic localities and at somewhat similar times. They have been devoted mainly to economically important species, though others on coastal and intertidal fish or on less- or non-commercial species provide insights on scales of temporal and spatial variation of parasite infracommunities. Later, we assess whether the probability of harbouring parasites depends on the host species body size. Our results indicate that a stronger tool for fish population studies may be developed under regular (long term) scrutiny of parasite communities, especially of small fish host species, due to their larger variability in richness, abundance and total biomass, than in large fish species. Finally, it might also be necessary to consider the effects of fishing on parasite communities as well as the natural oscillations (coupled or not) of host and parasite populations.
Voltas, Jordi; Lucabaugh, Devon; Chambel, Maria Regina; Ferrio, Juan Pedro
2015-12-01
The relevance of interspecific variation in the use of plant water sources has been recognized in drought-prone environments. By contrast, the characterization of intraspecific differences in water uptake patterns remains elusive, although preferential access to particular soil layers may be an important adaptive response for species along aridity gradients. Stable water isotopes were analysed in soil and xylem samples of 56 populations of the drought-avoidant conifer Pinus halepensis grown in a common garden test. We found that most populations reverted to deep soil layers as the main plant water source during seasonal summer droughts. More specifically, we detected a clear geographical differentiation among populations in water uptake patterns even under relatively mild drought conditions (early autumn), with populations originating from more arid regions taking up more water from deep soil layers. However, the preferential access to deep soil water was largely independent of aboveground growth. Our findings highlight the high plasticity and adaptive relevance of the differential access to soil water pools among Aleppo pine populations. The observed ecotypic patterns point to the adaptive relevance of resource investment in deep roots as a strategy towards securing a source of water in dry environments for P. halepensis. © 2015 The Authors. New Phytologist © 2015 New Phytologist Trust.
NASA Astrophysics Data System (ADS)
Baco-Taylor, A.
2006-12-01
Deep-sea precious corals (Gerardia sp., Corallium lauuense, and Corallium secundum) on the Islands and seamounts of the Hawaiian Archipelago have supported an extremely profitable fishery, yet little is known about the life history and dispersal of the exploited species. Recent studies indicate significant genetic structure between shallow-water coral populations, including several species capable of long distance dispersal. If significant genetic structure exists in seamount and Island populations of precious corals, this could suggest that the elimination (through overharvesting) of a bed of precious corals would result in loss of overall genetic diversity in the species. Here I discuss results based on microsatellite studies of the precious coral, Corallium secundum, from 11 sites in the Hawaiian Archipelago collected between 1998 and 2004, and compare the population genetic structure and dispersal capabilities of Corallium secundum to the results for Corallium lauuense. Microsatellite studies of Corallium lauuense indicated significant heterozygote deficiency in most populations, suggesting recruitment in most populations is from local sources with only occasional long-distance dispersal events. Also, two populations appear to be significantly isolated from other populations of Corallium lauuense and may be separate stocks. In contrast, Corallium secundum populations have little heterozygote deficiency and separate into 3 distinct regions. In addition to having fisheries management implications for these corals, the results of these studies also have implications for the management and protection of seamount fauna.
Sonsthagen, Sarah A.; McClaren, Erica L.; Doyle, Frank I.; Titus, K.; Sage, George K.; Wilson, Robert E.; Gust, Judy R.; Talbot, Sandra L.
2012-01-01
Northern Goshawks occupying the Alexander Archipelago, Alaska, and coastal British Columbia nest primarily in old-growth and mature forest, which results in spatial heterogeneity in the distribution of individuals across the landscape. We used microsatellite and mitochondrial data to infer genetic structure, gene flow, and fluctuations in population demography through evolutionary time. Patterns in the genetic signatures were used to assess predictions associated with the three population models: panmixia, metapopulation, and isolated populations. Population genetic structure was observed along with asymmetry in gene flow estimates that changed directionality at different temporal scales, consistent with metapopulation model predictions. Therefore, Northern Goshawk assemblages located in the Alexander Archipelago and coastal British Columbia interact through a metapopulation framework, though they may not fit the classic model of a metapopulation. Long-term population sources (coastal mainland British Columbia) and sinks (Revillagigedo and Vancouver islands) were identified. However, there was no trend through evolutionary time in the directionality of dispersal among the remaining assemblages, suggestive of a rescue-effect dynamic. Admiralty, Douglas, and Chichagof island complex appears to be an evolutionarily recent source population in the Alexander Archipelago. In addition, Kupreanof island complex and Kispiox Forest District populations have high dispersal rates to populations in close geographic proximity and potentially serve as local source populations. Metapopulation dynamics occurring in the Alexander Archipelago and coastal British Columbia by Northern Goshawks highlight the importance of both occupied and unoccupied habitats to long-term population persistence of goshawks in this region.
Age Dependent Variability in Gene Expression in Fischer 344 ...
Recent evidence suggests older adults may be a sensitive population with regard to environmental exposure to toxic compounds. One source of this sensitivity could be an enhanced variability in response. Studies on phenotypic differences have suggested that variation in response does increase with age. However, few reports address the question of variation in gene expression as an underlying cause for increased variability of phenotypic response in the aged. In this study, we utilized global analysis to compare variation in constitutive gene expression in the retinae of young (4 mos), middle-aged (11 mos) and aged (23 mos) Fischer 344 rats. Three hundred and forty transcripts were identified in which variance in expression increased from 4 to 23 mos of age, while only twelve transcripts were found for which it decreased. Functional roles for identified genes were clustered in basic biological categories including cell communication, function, metabolism and response to stimuli. Our data suggest that population stochastically-induced variability should be considered in assessing sensitivity due to old age. Recent evidence suggests older adults may be a sensitive population with regard to environmental exposure to toxic compounds. One source of this sensitivity could be an enhanced variability in response. Studies on phenotypic differences have suggested that variation in response does increase with age. However, few reports address the question of variation in
Chinese Students' Motivations for Studying in the United States
ERIC Educational Resources Information Center
Chao, Chiang-nan; Hegarty, Niall; Angelidis, John; Lu, Victor F.
2017-01-01
This study examines the presence of Chinese students in U.S., and attempts to explore the reasons why so many Chinese students choose to study abroad and why the United States is their preferred destination. This population is a vital component of university life at many colleges and a much needed source of financial revenue. The results indicate…
Tamil merchant in ancient Mesopotamia.
Palanichamy, Malliya Gounder; Mitra, Bikash; Debnath, Monojit; Agrawal, Suraksha; Chaudhuri, Tapas Kumar; Zhang, Ya-Ping
2014-01-01
Recent analyses of ancient Mesopotamian mitochondrial genomes have suggested a genetic link between the Indian subcontinent and Mesopotamian civilization. There is no consensus on the origin of the ancient Mesopotamians. They may be descendants of migrants, who founded regional Mesopotamian groups like that of Terqa or they may be merchants who were involved in trans Mesopotamia trade. To identify the Indian source population showing linkage to the ancient Mesopotamians, we screened a total of 15,751 mitochondrial DNAs (11,432 from the literature and 4,319 from this study) representing all major populations of India. Our results although suggest that south India (Tamil Nadu) and northeast India served as the source of the ancient Mesopotamian mtDNA gene pool, mtDNA of these ancient Mesopotamians probably contributed by Tamil merchants who were involved in the Indo-Roman trade.
NASA Astrophysics Data System (ADS)
Hafezalkotob, Ashkan; Mahmoudi, Reza
2017-09-01
Currently, many socially responsible governments adopt economic incentives and deterrents to manage environmental impacts of electricity suppliers. Considering the Stackelberg leadership of the government, the government's role in the competition of power plants in an electricity market is investigated. A one-population evolutionary game model of power plants is developed to study how their production strategy depends on tariffs levied by the government. We establish that a unique evolutionary stable strategy (ESS) for the population exists. Numerical examples demonstrate that revenue maximization and environment protection policies of the government significantly affect the production ESS of competitive power plants. The results reveal that the government can introduce a green energy source as an ESS of the competitive power plants by imposing appropriate tariffs.
SHEEP: The Search for the High Energy Extragalactic Population
NASA Technical Reports Server (NTRS)
Nandra, K.; Georgantopoulos, I.; Ptak, A.; Turner, T. J.; White, Nicholas E. (Technical Monitor)
2002-01-01
We present the SHEEP survey for serendipitously-detected hard X-ray sources in ASCA GIS images. In a survey area of approx. 40 sq deg, 69 sources were detected in the 5-10 keV band to a limiting flux of approx. 10(exp -13) erg/sq cm/s. The number counts agree with those obtained by the similar BeppoSAX HELLAS survey, and both are in close agreement with ASCA and BeppoSAX 2-10 keV surveys. Spectral analysis of the SHEEP sample reveals that the 2-10 and 5-10 keV surveys do not sample the same populations, however, as we find considerably harder spectra, with an average Gamma approx. 1.0 assuming no absorption. The implication is that the agreement in the number counts is coincidental, with the 5-10 keV surveys gaining approximately as many hard sources as they lose soft ones, when compared to the 2-10 keV surveys. This is hard to reconcile with standard AGN "population synthesis" models for the X-ray background, which posit the existence of a large population of absorbed sources. We find no evidence of the population hardening at faint fluxes, with the exception that the few very brightest objects are anomalously soft. 53 of the SHEEP sources have been covered by ROSAT in the pointed phase. Of these 32 were detected. An additional 3 were detected in the RASS. As expected the sources detected with ROSAT are systematically softer than those detected with ASCA alone, and of the sample as a whole. Although they represent a biased subsample, the ROSAT positions allow relatively secure catalog identifications to be made. We find associations with a wide variety of AGN and a few clusters and groups. At least two X-ray sources identified with high-z QSOs present very hard X-ray spectra indicative of absorption, despite the presence of broad optical lines. A possible explanation for this is that we are seeing relatively dust-free "warm absorbers" in high luminosity/redshift objects. Our analysis defines a new, hard X-ray selected sample of objects - mostly active galactic nuclei - which is less prone to bias due to obscuration than previous optical or soft X-ray samples. They are therefore more representative of the population of AGN in the universe in general, and the SHEEP survey should produce bright examples of the sources that make up the hard X-ray background, the majority of which has recently been resolved by Chandra. This should help elucidate the nature of the new populations.
Atmospheric transport of ozone between Southern and Eastern Asia.
Chakraborty, T; Beig, G; Dentener, F J; Wild, O
2015-08-01
This study describes the effect of pollution transport between East Asia and South Asia on tropospheric ozone (O3) using model results from the Task Force on Hemispheric Transport of Air Pollution (TF HTAP). Ensemble mean O3 concentrations are evaluated against satellite-data and ground observations of surface O3 at four stations in India. Although modeled surface O3 concentrations are 1020ppb higher than those observed, the relative magnitude of the seasonal cycle of O3 is reproduced well. Using 20% reductions in regional anthropogenic emissions, we quantify the seasonal variations in pollution transport between East Asia and South Asia. While there is only a difference of 0.05 to 0.1ppb in the magnitudes of the regional contributions from one region to the other, O3 from East Asian sources affects the most densely populated parts of South Asia while Southern Asian sources only partly affect the populated parts of East Asia. We show that emission changes over East Asia between 2000 and 2010 had a larger impact on populated parts of South Asia than vice versa. This study will help inform future decisions on emission control policy over these regions. Copyright © 2015 Elsevier B.V. All rights reserved.
A study of the cold cores population in the Perseus star-forming regions.
NASA Astrophysics Data System (ADS)
Pezzuto, S.; Fiorellino, E.; Benedettini, M.; Schisano, E.; Elia, D.; André, P.; Könyves, V.; Ladjelate, B.; Di Francesco, J.; Piccotti, L.; Herschel Gould Belt Survey Consortium
As part of the Herschel Gould Belt survey, the Perseus star-forming cloud was observed with the Herschel PACS and SPIRE instruments. Source catalogs are preliminary, as well as the here presented core mass function.
Variation in worldwide incidence of amyotrophic lateral sclerosis: a meta-analysis.
Marin, Benoît; Boumédiene, Farid; Logroscino, Giancarlo; Couratier, Philippe; Babron, Marie-Claude; Leutenegger, Anne Louise; Copetti, Massimilano; Preux, Pierre-Marie; Beghi, Ettore
2017-02-01
To assess the worldwide variation of amyotrophic lateral sclerosis (ALS) incidence, we performed a systematic review and meta-analysis of population-based data published to date. We reviewed Medline and Embase up to June 2015 and included all population-based studies of newly diagnosed ALS cases, using multiple sources for case ascertainment. ALS crude and standardized incidence (on age and sex using the US 2010 population) were calculated. Random effect meta-analysis and meta-regression were performed using the subcontinent as the main study level covariate. Sources of heterogeneity related to the characteristics of the study population and the study methodology were investigated. Among 3216 records, 44 studies were selected, covering 45 geographical areas in 11 sub-continents. A total of 13 146 ALS cases and 825 million person-years of follow-up (PYFU) were co-nsidered. The overall pooled worldwide crude ALS incidence was at 1.75 (1.55-1.96)/100 000 PYFU; 1.68 (1.50-1.85)/100 000 PYFU after standardization. Heterogeneity was identified in ALS standardized incidence between North Europe [1.89 (1.46-2.32)/100 000 PYFU] and East Asia [0.83 (0.42-1.24)/100 000 PYFU, China and Japan P = 0.001] or South Asia [0.73 (0.58-0.89)/100 000/PYFU Iran, P = 0.02]. Conversely, homogeneous rates have been reported in populations from Europe, North America and New Zealand [pooled ALS standardized incidence of 1.81 (1.66-1.97)/100 000 PYFU for those areas]. This review confirms a heterogeneous distribution worldwide of ALS, and sets the scene to sustain a collaborative study involving a wide international consortium to investigate the link between ancestry, environment and ALS incidence. © The Author 2016. Published by Oxford University Press on behalf of the International Epidemiological Association
Ship noise extends to frequencies used for echolocation by endangered killer whales
Veirs, Val; Wood, Jason D.
2016-01-01
Combining calibrated hydrophone measurements with vessel location data from the Automatic Identification System, we estimate underwater sound pressure levels for 1,582 unique ships that transited the core critical habitat of the endangered Southern Resident killer whales during 28 months between March, 2011, and October, 2013. Median received spectrum levels of noise from 2,809 isolated transits are elevated relative to median background levels not only at low frequencies (20–30 dB re 1 µPa2/Hz from 100 to 1,000 Hz), but also at high frequencies (5–13 dB from 10,000 to 96,000 Hz). Thus, noise received from ships at ranges less than 3 km extends to frequencies used by odontocetes. Broadband received levels (11.5–40,000 Hz) near the shoreline in Haro Strait (WA, USA) for the entire ship population were 110 ± 7 dB re 1 µPa on average. Assuming near-spherical spreading based on a transmission loss experiment we compute mean broadband source levels for the ship population of 173 ± 7 dB re 1 µPa 1 m without accounting for frequency-dependent absorption. Mean ship speed was 7.3 ± 2.0 m/s (14.1 ± 3.9 knots). Most ship classes show a linear relationship between source level and speed with a slope near +2 dB per m/s (+1 dB/knot). Spectrum, 1/12-octave, and 1/3-octave source levels for the whole population have median values that are comparable to previous measurements and models at most frequencies, but for select studies may be relatively low below 200 Hz and high above 20,000 Hz. Median source spectrum levels peak near 50 Hz for all 12 ship classes, have a maximum of 159 dB re 1 µPa2/Hz @ 1 m for container ships, and vary between classes. Below 200 Hz, the class-specific median spectrum levels bifurcate with large commercial ships grouping as higher power noise sources. Within all ship classes spectrum levels vary more at low frequencies than at high frequencies, and the degree of variability is almost halved for classes that have smaller speed standard deviations. This is the first study to present source spectra for populations of different ship classes operating in coastal habitats, including at higher frequencies used by killer whales for both communication and echolocation. PMID:27004149
Isolation mediates persistent founder effects on zooplankton colonisation in new temporary ponds
Badosa, Anna; Frisch, Dagmar; Green, Andy J.; Rico, Ciro; Gómez, Africa
2017-01-01
Understanding the colonisation process in zooplankton is crucial for successful restoration of aquatic ecosystems. Here, we analyzed the clonal and genetic structure of the cyclical parthenogenetic rotifer Brachionus plicatilis by following populations established in new temporary ponds during the first three hydroperiods. Rotifer populations established rapidly after first flooding, although colonisation was ongoing throughout the study. Multilocus genotypes from 7 microsatellite loci suggested that most populations (10 of 14) were founded by few clones. The exception was one of the four populations that persisted throughout the studied hydroperiods, where high genetic diversity in the first hydroperiod suggested colonisation from a historical egg bank, and no increase in allelic diversity was detected with time. In contrast, in another of these four populations, we observed a progressive increase of allelic diversity. This population became less differentiated from the other populations suggesting effective gene flow soon after its foundation. Allelic diversity and richness remained low in the remaining two, more isolated, populations, suggesting little gene flow. Our results highlight the complexity of colonisation dynamics, with evidence for persistent founder effects in some ponds, but not in others, and with early immigration both from external source populations, and from residual, historical diapausing egg banks. PMID:28276459
Isolation mediates persistent founder effects on zooplankton colonisation in new temporary ponds
NASA Astrophysics Data System (ADS)
Badosa, Anna; Frisch, Dagmar; Green, Andy J.; Rico, Ciro; Gómez, Africa
2017-03-01
Understanding the colonisation process in zooplankton is crucial for successful restoration of aquatic ecosystems. Here, we analyzed the clonal and genetic structure of the cyclical parthenogenetic rotifer Brachionus plicatilis by following populations established in new temporary ponds during the first three hydroperiods. Rotifer populations established rapidly after first flooding, although colonisation was ongoing throughout the study. Multilocus genotypes from 7 microsatellite loci suggested that most populations (10 of 14) were founded by few clones. The exception was one of the four populations that persisted throughout the studied hydroperiods, where high genetic diversity in the first hydroperiod suggested colonisation from a historical egg bank, and no increase in allelic diversity was detected with time. In contrast, in another of these four populations, we observed a progressive increase of allelic diversity. This population became less differentiated from the other populations suggesting effective gene flow soon after its foundation. Allelic diversity and richness remained low in the remaining two, more isolated, populations, suggesting little gene flow. Our results highlight the complexity of colonisation dynamics, with evidence for persistent founder effects in some ponds, but not in others, and with early immigration both from external source populations, and from residual, historical diapausing egg banks.
Ando, Wataru; Kutcher, Josh J; Krawetz, Roman; Sen, Arindom; Nakamura, Norimasa; Frank, Cyril B; Hart, David A
2014-06-01
Previous studies have demonstrated that porcine synovial membrane stem cells can adhere to a cartilage defect in vivo through the use of a tissue-engineered construct approach. To optimize this model, we wanted to compare effectiveness of tissue sources to determine whether porcine synovial fluid, synovial membrane, bone marrow and skin sources replicate our understanding of synovial fluid mesenchymal stromal cells or mesenchymal progenitor cells from humans both at the population level and the single-cell level. Synovial fluid clones were subsequently isolated and characterized to identify cells with a highly characterized optimal phenotype. The chondrogenic, osteogenic and adipogenic potentials were assessed in vitro for skin, bone marrow, adipose, synovial fluid and synovial membrane-derived stem cells. Synovial fluid cells then underwent limiting dilution analysis to isolate single clonal populations. These clonal populations were assessed for proliferative and differentiation potential by use of standardized protocols. Porcine-derived cells demonstrated the same relationship between cell sources as that demonstrated previously for humans, suggesting that the pig may be an ideal preclinical animal model. Synovial fluid cells demonstrated the highest chondrogenic potential that was further characterized, demonstrating the existence of a unique clonal phenotype with enhanced chondrogenic potential. Porcine stem cells demonstrate characteristics similar to those in human-derived mesenchymal stromal cells from the same sources. Synovial fluid-derived stem cells contain an inherent phenotype that may be optimal for cartilage repair. This must be more fully investigated for future use in the in vivo tissue-engineered construct approach in this physiologically relevant preclinical porcine model. Copyright © 2014 International Society for Cellular Therapy. Published by Elsevier Inc. All rights reserved.
Zenni, Rafael D; Hoban, Sean M
2015-07-01
Identifying the genes underlying rapid evolutionary changes, describing their function and ascertaining the environmental pressures that determine fitness are the central elements needed for understanding of evolutionary processes and phenotypic changes that improve the fitness of populations. It has been hypothesized that rapid adaptive changes in new environments may contribute to the rapid spread and success of invasive plants and animals. As yet, studies of adaptation during invasion are scarce, as is knowledge of the genes underlying adaptation, especially in multiple replicated invasions. Here, we quantified how genotype frequencies change during invasions, resulting in rapid evolution of naturalized populations. We used six fully replicated common garden experiments in Brazil where Pinus taeda (loblolly pine) was introduced at the same time, in the same numbers, from the same seed sources, and has formed naturalized populations expanding outward from the plantations. We used a combination of nonparametric, population genetics and multivariate statistics to detect changes in genotype frequencies along each of the six naturalization gradients and their association with climate as well as shifts in allele frequencies compared to the source populations. Results show 25 genes with significant shifts in genotype frequencies. Six genes had shifts in more than one population. Climate explained 25% of the variation in the groups of genes under selection across all locations, but specific genes under strong selection during invasions did not show climate-related convergence. In conclusion, we detected rapid evolutionary changes during invasive range expansions, but the particular gene-level patterns of evolution may be population specific. © 2015 John Wiley & Sons Ltd.
Factors affecting winter survival of female mallards in the lower Mississippi alluvial valley
Davis, B.E.; Afton, A.D.; Cox, R.R.
2011-01-01
The lower Mississippi Alluvial Valley (hereafter LMAV) provides winter habitat for approximately 40% of the Mississippi Flyway's Mallard (Anas platyrhynhcos) population; information on winter survival rates of female Mallards in the LMAV is restricted to data collected prior to implementation of the North American Waterfowl Management Plan. To estimate recent survival and cause-specific mortality rates in the LMAV, 174 radio-marked female Mallards were tracked for a total of 11,912 exposure days. Survival varied by time periods defined by hunting seasons, and females with lower body condition (size adjusted body mass) at time of capture had reduced probability of survival. Female survival was less and the duration of our tracking period was greater than those in previous studies of similarly marked females in the LMAV; the product-limit survival estimate (??????SE) through the entire tracking period (136 days) was 0.54 ??0.10. Cause-specific mortality rates were 0.18 ??0.04 and 0.34 ??0.12 for hunting and other sources of mortality, respectively; the estimated mortality rate from other sources (including those from avian, mammalian, or unknown sources) was higher than mortality from non-hunting sources reported in previous studies of Mallards in the LMAV. Models that incorporate winter survival estimates as a factor in Mallard population growth rates should be adjusted for these reduced winter survival estimates.
Deaf Adolescents' Learning of Cardiovascular Health Information: Sources and Access Challenges.
Smith, Scott R; Kushalnagar, Poorna; Hauser, Peter C
2015-10-01
Deaf individuals have more cardiovascular risks than the general population that are believed to be related to their cardiovascular health knowledge disparities. This phenomenological study describes where 20 deaf sign language-using adolescents from Rochester, New York, many who possess many positive characteristics to support their health literacy, learn cardiovascular health information and their lived experiences accessing health information. The goal is to ultimately use this information to improve the delivery of cardiovascular health education to this population and other deaf adolescents at a higher risk for weak health literacy. Deaf bilingual researchers interviewed deaf adolescents, transcribed and coded the data, and described the findings. Five major sources of cardiovascular health information were identified including family, health education teachers, healthcare providers, printed materials, and informal sources. Despite possessing advantageous characteristics contributing to stronger health literacy, study participants described significant challenges with accessing health information from each source. They also demonstrated inconsistencies in their cardiovascular health knowledge, especially regarding heart attack, stroke, and cholesterol. These findings suggest a great need for additional public funding to research deaf adolescents' informal health-related learning, develop accessible and culturally appropriate health surveys and health education programming, improve interpreter education, and disseminate information through social media. © The Author 2015. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.
Elevated carboxyhemoglobin: sources of carbon monoxide exposure.
Buchelli Ramirez, Herminia; Fernández Alvarez, Ramón; Rubinos Cuadrado, Gemma; Martinez Gonzalez, Cristina; Rodriguez Jerez, Francisco; Casan Clara, Pere
2014-11-01
Inhalation of carbon monoxide (CO) can result in poisoning, with symptoms ranging from mild and nonspecific to severe, or even death. CO poisoning is often underdiagnosed because exposure to low concentrations goes unnoticed, and threshold values for normal carboxyhemoglobin vary according to different authors. The aim of our study was to analyze carboxyhemoglobin (COHb) levels in an unselected population and detect sources of CO exposure In a cross-sectional descriptive study, we analyzed consecutive arterial blood gas levels processed in our laboratory. We selected those with COHb≥2.5% in nonsmokers and ≥5% in smokers. In these cases a structured telephone interview was conducted. Elevated levels of COHb were found in 64 (20%) of 306 initial determinations. Of these, data from 51 subjects aged 65±12 years, 31 (60%) of which were men, were obtained. Mean COHb was 4.0%. Forty patients (78%) were non-smokers with mean COHb of 3.2%, and 11 were smokers with COHb of 6.7%. In 45 patients (88.2%) we detected exposure to at least one source of ambient CO other than cigarette smoke. A significant proportion of individuals from an unselected sample had elevated levels of COHb. The main sources of CO exposure were probably the home, so this possibility should be explored. The population should be warned about the risks and encouraged to take preventive measures. Copyright © 2013 SEPAR. Published by Elsevier Espana. All rights reserved.
Robinson, G.R.; Kapo, K.E.
2004-01-01
Aggregate is used in road and building construction to provide bulk, strength, support, and wear resistance. Reclaimed asphalt pavement (RAP) and reclaimed Portland cement concrete (RPCC) are abundant and available sources of recycled aggregate. In this paper, current aggregate production operations in Virginia, Maryland, and the District of Columbia are used to develop spatial association models for the recycled aggregate industry with regional transportation network and population density features. The cost of construction aggregate to the end user is strongly influenced by the cost of transporting processed aggregate from the production site to the construction site. More than 60% of operations recycling aggregate in the mid-Atlantic study area are located within 4.8 km (3 miles) of an interstate highway. Transportation corridors provide both sites of likely road construction where aggregate is used and an efficient means to move both materials and on-site processing equipment back and forth from various work sites to the recycling operations. Urban and developing areas provide a high market demand for aggregate and a ready source of construction debris that may be processed into recycled aggregate. Most aggregate recycling operators in the study area are sited in counties with population densities exceeding 77 people/km2 (200 people/mile 2). No aggregate recycling operations are sited in counties with less than 19 people/km2 (50 people/mile2), reflecting the lack of sufficient long-term sources of construction debris to be used as an aggregate source, as well as the lack of a sufficient market demand for aggregate in most rural areas to locate a recycling operation there or justify the required investment in the equipment to process and produce recycled aggregate. Weights of evidence analyses (WofE), measuring correlation on an area-normalized basis, and weighted logistic regression (WLR), are used to model the distribution of RAP and RPCC operations relative to transportation network and population distribution data. The models can be used on a regional scale to quickly map the relative site suitability for a RAP or RPCC aggregate recycling operation in a particular area based on transportation network and population parameters. The results can be used to identify general areas to be further evaluated on a site-specific basis using more detailed marketplace information. As transportation or population features change due to planning or actual development, the models can be easily revised to reflect these changes. ?? 2004 Elsevier B.V. All rights reserved.
Reliance on deep soil water in the tree species Argania spinosa.
Zunzunegui, M; Boutaleb, S; Díaz Barradas, M C; Esquivias, M P; Valera, J; Jáuregui, J; Tagma, T; Ain-Lhout, F
2017-12-07
In South-western Morocco, water scarcity and high temperature are the main factors determining species survival. Argania spinosa (L.) Skeels is a tree species, endemic to Morocco, which is suffering from ongoing habitat shrinkage. Argan trees play essential local ecological and economic roles: protecting soils from erosion, shading different types of crops, helping maintain soil fertility and, even more importantly, its seeds are used by the local population for oil production, with valuable nutritional, medicinal and cosmetic purposes. The main objective of this study was to identify the sources of water used by this species and to assess the effect of water availability on the photosynthetic rate and stem water potential in two populations: one growing on the coast and a second one 10 km inland. Stem water potential, photosynthetic rate and xylem water isotopic composition (δ18O) were seasonally monitored during 2 years. Trees from both populations showed a similar strategy in the use of the available water sources, which was strongly dependent on deep soil water throughout the year. Nevertheless, during the wet season or under low precipitation a more complex water uptake pattern was found with a mixture of water sources, including precipitation and soil at different depths. No evidence was found of the use of either groundwater or atmospheric water in this species. Despite the similar water-use strategy, the results indicate that Argania trees from the inland population explored deeper layers than coastal ones as suggested by more depleted δ18O values recorded in the inland trees and better photosynthetic performance, hence suggesting that the coastal population of A. spinosa could be subjected to higher stress. © The Author 2017. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.
NASA Astrophysics Data System (ADS)
Ustaömer, Timur; Ayda Ustaömer, Petek; Robertson, Alastair H. F.; Gerdes, Axel; Zulauf, Gernold
2014-05-01
We present new U-Pb zircon source age data for Upper Triassic sandstones of the Istanbul Terrane (S Eurasian margin) and also for Triassic sandstones of the Taurides (N Gondwana margin). The main aim is to detect and quantify the contribution of Triassic magmatism as detritus to either of these crustal blocks. This follows the recent discovery of a Triassic magmatic arc source for the Triassic sandstones of the Palaeotethyan Karakaya subduction-accretion complex (Ustaömer et al. 2013; this meeting). Carboniferous (Variscan) zircon grains also form a significant detrital population, plus several more minor populations. Six sandstone samples were studied, two from the İstanbul Terrane (Bakırlıkıran Formation of the Kocaeli Triassic Basin) and four from the Tauride Autochthon (latest Triassic Üzümdere Formation and Mid-Triassic Kasımlar Formations; Beyşehir region). Detrital zircon grains were dated by the laser ablation-inductively coupled plasma-mass spectrometer (LA-ICP-MS) U-Pb method at Goethe University, Frankfurt. Our results do not reveal Triassic detritus in the Üzümdere Formation. The U-Pb age of the analysed zircon grains ranges from 267 Ma to 3.2 Ga. A small fraction of Palaeozoic zircons are Permian (267 to 296 Ma), whereas the remainder are Early Palaeozoic. Ordovician grains (4%) form two age clusters, one at ca. 450 Ma and the other at ca. 474 Ma. Cambrian-aged grains dominate the zircon population, while the second largest population is Ediacaran (576 to 642 Ma). Smaller populations occur at 909-997 Ma, 827-839 Ma, 1.8-2.0 Ga and 2.4-2.6 Ga. The sandstones of the Kasımlar Formation have similar zircon age cluster to those of the somewhat younger Üzümdere Formation, ranging from 239 Ma to 2.9 Ga. A few grains gave Anisian ages. Cambrian zircon grains are less pronounced than in the Kasımlar Formation compared to the Üzümdere Formation. The detrital zircon record of Tauride sandstones, therefore, not indicates significant contribution of Triassic or Carboniferous (Variscan) arc sources, in marked contrast to those of the Triassic Karakaya subduction complex. In comparison, the ages of the analysed zircons in the Upper Triassic sandstones of the Istanbul Terrane range from 294 Ma to 3.1 Ga. Triassic zircons are again absent, while Variscan-aged zircons (294 to 339 Ma) dominate the zircon population. Additional zircon populations are dated at 554 to 655 Ma, 0.9 to 1.2 Ga, 1.5 Ga, 1.65 Ga, 2.0 to 2.15 and 2.5 to 2.8 Ga. The Precambrian zircon age spectra are compatible with derivation from an Avalonian/Amazonian/Baltic crustal provenance. In summary, there is no evidence in either the Triassic sandstones of the İstanbul Terrane or of the Taurides of the Triassic magmatic arc source that dominates the Triassic Karakaya subduction-accretion complex. Where then was the source of the Karakaya arc detritus? A likely option is that the Karakaya subduction-accretion complex is an exotic terrane that was detached from a source magmatic arc and displaced to its present location, probably prior the initial deposition of the Early Jurassic cover sediments. This study was supported by TUBITAK, Project No: 111R015
Identifying exposure disparities in air pollution epidemiology specific to adverse birth outcomes
NASA Astrophysics Data System (ADS)
Geer, Laura A.
2014-10-01
More than 147 million people in the US live in areas where pollutant levels are above regulatory limits and pose a risk to health. Most of the vast network of air pollutant monitors in the US are located in places with higher pollution levels and a higher density of pollutant sources (e.g., point sources from industrial pollution). Vulnerable populations are more likely to live closer to pollutant sources, and thus closer to pollutant monitors. These differential exposures have an impact on maternal and child health; maternal air pollutant exposures have been linked to adverse outcomes such as preterm birth and infant low birth weight. Several studies are highlighted that address methodological approaches in the study of air pollution and health disparities.
NPTFit: A Code Package for Non-Poissonian Template Fitting
DOE Office of Scientific and Technical Information (OSTI.GOV)
Mishra-Sharma, Siddharth; Rodd, Nicholas L.; Safdi, Benjamin R., E-mail: smsharma@princeton.edu, E-mail: nrodd@mit.edu, E-mail: bsafdi@mit.edu
We present NPTFit, an open-source code package, written in Python and Cython, for performing non-Poissonian template fits (NPTFs). The NPTF is a recently developed statistical procedure for characterizing the contribution of unresolved point sources (PSs) to astrophysical data sets. The NPTF was first applied to Fermi gamma-ray data to provide evidence that the excess of ∼GeV gamma-rays observed in the inner regions of the Milky Way likely arises from a population of sub-threshold point sources, and the NPTF has since found additional applications studying sub-threshold extragalactic sources at high Galactic latitudes. The NPTF generalizes traditional astrophysical template fits to allowmore » for the ability to search for populations of unresolved PSs that may follow a given spatial distribution. NPTFit builds upon the framework of the fluctuation analyses developed in X-ray astronomy, thus it likely has applications beyond those demonstrated with gamma-ray data. The NPTFit package utilizes novel computational methods to perform the NPTF efficiently. The code is available at http://github.com/bsafdi/NPTFit and up-to-date and extensive documentation may be found at http://nptfit.readthedocs.io.« less
Wong, Sabrina T; Yoo, Grace J; Stewart, Anita L
2005-01-01
This study explored social support domains and actual sources of support for older Chinese and Korean immigrants and compared them to the traditional domains based on mainly White, middle class populations. Fifty-two older Cantonese and Korean speaking immigrants participated in one of eight focus groups. We identified four similar domains: tangible, information/advice, emotional support, and companionship. We also identified needing language support which is relevant for non-English speaking minority populations. Participants discussed not needing emotional support. These Chinese and Korean immigrants had a small number of actual sources of support, relying mainly on adult children for help with personal situations (e.g., carrying heavy groceries, communicating with physicians) and friends for general information/advice (e.g., learning how to speak English, applying for citizenship) and companionship. Immigrant Asians are caught between two different traditions; one that is strongly kinship oriented where needs and desires are subordinated to the interests of the family and one that values independence and celebrates individuality. Despite their reticence in asking for help outside the family, elders are seeking help from other sources, such as ethnic churches and the government.
Stellar Clusters in the NGC 6334 Star-Forming Complex
NASA Astrophysics Data System (ADS)
Feigelson, Eric D.; Martin, Amanda L.; McNeill, Collin J.; Broos, Patrick S.; Garmire, Gordon P.
2009-07-01
The full stellar population of NGC 6334, one of the most spectacular regions of massive star formation in the nearby Galaxy, has not been well sampled in past studies. We analyze here a mosaic of two Chandra X-ray Observatory images of the region using sensitive data analysis methods, giving a list of 1607 faint X-ray sources with arcsecond positions and approximate line-of-sight absorption. About 95% of these are expected to be cluster members, most lower mass pre-main-sequence stars. Extrapolating to low X-ray levels, the total stellar population is estimated to be 20,000-30,000 pre-main-sequence stars. The X-ray sources show a complicated spatial pattern with ~10 distinct star clusters. The heavily obscured clusters are mostly associated with previously known far-infrared sources and radio H II regions. The lightly obscured clusters are mostly newly identified in the X-ray images. Dozens of likely OB stars are found, both in clusters and dispersed throughout the region, suggesting that star formation in the complex has proceeded over millions of years. A number of extraordinarily heavily absorbed X-ray sources are associated with the active regions of star formation.
Clennon, J A; King, C H; Muchiri, E M; Kitron, U
2007-05-01
Urinary schistosomiasis is an important source of human morbidity in Msambweni, Kenya, where the intermediate host snail, Bulinus nasutus is found in ponds and water pools. In the past, aquatic habitats in the area have been studied separately; however, recent collections of B. nasutus snails and shells indicated that many of these ponds are in fact connected during and following sufficient rains. Satellite imagery and a geographical information system (GIS) were used to survey the main water courses and potential drainage routes, to locate potential source populations of snails and to determine probable snail dispersal routes. The 2 water bodies implicated as being the most important Schistosoma haematobium transmission foci in the area were found to differ in their degree of connectivity to other B. nasutus source habitats. One pond becomes connected even after normal rains, while the other pond requires prolonged rains or flooding to become connected with source habitats. Consequently, the transmission foci differ in their susceptibility to snail population control measures. Spatially explicit dispersal models that consider the spatial and temporal patterns of connectivity between aquatic habitats will contribute to improved snail surveillance and more focused control for urinary schistosomiasis at a local level.
X-ray Source Populations in Old Open Clusters - Collinder 261
NASA Astrophysics Data System (ADS)
Vats, Smriti
2014-11-01
We are carrying out an X-ray survey of old open clusters (OCs) with the Chandra X-ray Observatory. Single old stars emit very faint X-rays, making X-rays produced by mass transfer in CVs, or by rapid rotation of the stars in tidally-locked, detached binaries detectable, without contamination from single stars. By comparing properties of interacting binaries in different environments, we aim to study binary evolution, and how dynamical encounters with other cluster members affect it. Collinder (Cr) 261 is an old OC(~7Gyr), with one of the richest populations inferred, of close binary populations and blue stragglers of all OCs. We will present the first results, detailing the X-ray population of Cr 261, in conjugation with other OCs, and in comparison with populations in globular clusters.
NASA Technical Reports Server (NTRS)
Marsden, Danica; Gralla, Megan; Marriage, Tobias A.; Switzer, Eric R.; Partridge, Bruce; Massardi, Marcella; Morales, Gustavo; Addison, Graeme; Bond, J. Richard; Crichton, Devin;
2013-01-01
We present a catalog of 191 extragalactic sources detected by the Atacama Cosmology Telescope (ACT) at 148 GHz and/or 218GHz in the 2008 Southern survey. Flux densities span 14-1700mJy, and we use source spectral indices derived using ACT-only data to divide our sources into two sub-populations: 167 radio galaxies powered by central active galactic nuclei (AGN), and 24 dusty star-forming galaxies (DSFGs). We cross-identify 97% of our sources (166 of the AGN and 19 of the DSFGs) with those in currently available catalogs. When combined with flux densities from the Australian Telescope 20 GHz survey and follow-up observations with the Australia Telescope Compact Array, the synchrotron-dominated population is seen to exhibit a steepening of the slope of the spectral energy distribution from 20 to 148GHz, with the trend continuing to 218GHz. The ACT dust-dominated source population has a median spectral index, alpha(sub 148-218), of 3.7+0.62 or -0.86, and includes both local galaxies and sources with redshifts as great as 5.6. Dusty sources with no counterpart in existing catalogs likely belong to a recently discovered subpopulation of DSFGs lensed by foreground galaxies or galaxy groups.
A longitudinal particulate matter (PM) exposure study was conducted in the Research Triangle Park, NC area between June 2000 and June 2001. Participants were selected from two groups of potentially susceptible sub-populations: a group of African-Americans living in an environme...
Meaningful Commitment: Finding Meaning in Volunteer Work
ERIC Educational Resources Information Center
Schnell, Tatjana; Hoof, Matthias
2012-01-01
This study tests the hypothesis that volunteer work is associated with various aspects of meaning making by employing a multi-dimensional model of meaning operationalized by the "Sources of Meaning and Meaning in Life Questionnaire" ("SoMe"). An empirical study comparing 168 volunteers with a representative sample of the general population (N =…
Probing dim point sources in the inner Milky Way using PCAT
NASA Astrophysics Data System (ADS)
Daylan, Tansu; Portillo, Stephen K. N.; Finkbeiner, Douglas P.
2017-01-01
Poisson regression of the Fermi-LAT data in the inner Milky Way reveals an extended gamma-ray excess. An important question is whether the signal is coming from a collection of unresolved point sources, possibly old recycled pulsars, or constitutes a truly diffuse emission component. Previous analyses have relied on non-Poissonian template fits or wavelet decomposition of the Fermi-LAT data, which find evidence for a population of dim point sources just below the 3FGL flux limit. In order to be able to draw conclusions about the flux distribution of point sources at the dim end, we employ a Bayesian trans-dimensional MCMC framework by taking samples from the space of catalogs consistent with the observed gamma-ray emission in the inner Milky Way. The software implementation, PCAT (Probabilistic Cataloger), is designed to efficiently explore that catalog space in the crowded field limit such as in the galactic plane, where the model PSF, point source positions and fluxes are highly degenerate. We thus generate fair realizations of the underlying MSP population in the inner galaxy and constrain the population characteristics such as the radial and flux distribution of such sources.
The internet as a source of health information in three disparate communities.
Dart, Jared
2008-08-01
A survey questionnaire was designed and implemented across three different communities to determine the current utilisation, importance, trust and future preference for the internet as a source of health information in three different socioeconomic groups. The following were the key results. Fewer respondents in the low socioeconomic group accessed online health information than the mid-high socioeconomic or university samples. The internet was a much more important source of health information for the university sample. The use of online health information and the importance ascribed to the internet as a source of health information was related to home internet access and the frequency of internet use in all three populations. Most respondents do not bring online health information to their doctor (>70% of those who access online health information). Age alone did not relate to the current use of the internet as a source of health information. Most respondents in all populations did not trust the internet. In all populations the internet was a more preferred source of health information than its current use would suggest, especially among those with home internet access and frequent users of the internet.
The Jerusalem Perinatal Study cohort, 1964–2005: methods and a review of the main results
Harlap, Susan; Davies, A. Michael; Deutsch, Lisa; Calderon-Margalit, Ronit; Manor, Orly; Paltiel, Ora; Tiram, Efrat; Yanetz, Rivka; Perrin, Mary C.; Terry, Mary B.; Malaspina, Dolores; Friedlander, Yechiel
2010-01-01
Summary The Jerusalem Perinatal Study recorded information on population-based cohorts of 92 408 live- and stillbirths in 1964–76, and their parents, with active surveillance of infant deaths and birth defects. Data on maternal conditions, obstetric complications and interventions during labour and delivery were recorded for 92% of the births. Subsets were surveyed with antenatal interviews in 1965–68 (n = 11 467), paediatric admissions to hospital (n = 17 782) and postpartum interviews in 1975–76 (n = 16 912). Data from some offspring were linked to records of a health examination at age 17. The offspring, mothers and fathers have been traced recently, their vital status assessed, and the data linked to Israel’s Cancer Registry and Psychiatric Registry. This paper describes the different types of data available, their sources, and some potential biases. Characteristics of this unique population are shown. Findings from the study are reviewed and a list of references is provided. The cohorts provide a unique source of data for a wide variety of studies. PMID:17439536
Andrews, Tessa M.; Shepard, Bradley B.; Litt, Andrea R.; Kruse, Carter G.; Zale, Alexander V.; Kalinowski, Steven T.
2013-01-01
Translocations are frequently used to increase the abundance and range of endangered fishes. One factor likely to affect the outcome of translocations is fish movement. We introduced embryos from five Westslope Cutthroat Trout Oncorhynchus clarkii lewisi populations (both hatchery and wild) at five different locations within a fishless watershed. We then examined the movement of age-1 and age-2 fish and looked for differences in movement distance among source populations and among introduction sites; we also examined the interactions among age, population, and introduction site. At age 1, most individuals (90.9%) remained within 1,000 m their introduction sites. By age 2, the majority of individuals (58.3%) still remained within 1,000 m of their introduction site, but considerably more individuals had moved downstream, some more than 6,000 m from their introduction site. We observed a significant interaction between age and source population (F 4, 1077 = 15.45, P 4, 1077 = 11.39, P < 0.0008), so we presented results in the context of these interactions. Within age-groups, we observed differences in movement behavior among source populations and among donor populations of Westslope Cutthroat Trout. We discuss these findings in light of previous research on juvenile salmonid movement.
Baller, Julia B; McGinty, Emma E; Azrin, Susan T; Juliano-Bult, Denise; Daumit, Gail L
2015-03-21
Adults with serious mental illness have a mortality rate two to three times higher than the overall US population, much of which is due to somatic conditions, especially cardiovascular disease. Given the disproportionately high prevalence of cardiovascular risk factors in the population with SMI, screening for these conditions is an important first step for timely diagnosis and appropriate treatment. This comprehensive literature review summarizes screening rates for cardiovascular risk factors in the population with serious mental illness. Relevant articles published between 2000 and 2013 were identified using the EMBASE, PsychInfo, PubMed, SCOPUS and Web of Science databases. We reviewed 10 studies measuring screening rates for obesity, diabetes, dyslipidemia, and hypertension in the population with serious mental illness. Two reviewers independently extracted information on screening rates, study population, and study setting. Rates of screening varied considerably by time period, study population, and data source for all medical conditions. For example, rates of lipid testing for antipsychotic users ranged from 6% to 85%. For some conditions, rates of screening were consistently high. For example, screening rates for hypertension ranged from 79% - 88%. There is considerable variation in screening of cardiovascular risk factors in the population with serious mental illness, with significant need for improvement in some study populations and settings. Implementation of standard screening protocols triggered by diagnosis of serious mental illness or antipsychotic use may be promising avenues for ensuring timely diagnosis and treatment of cardiovascular risk factors in this population.
Aunins, Aaron W.; Petty, J. Todd; King, Timothy L.; Schilz, Mariya; Mazik, Patricia M.
2015-01-01
Brook trout (Salvelinus fontinalis) often exist as highly differentiated populations, even at small spatial scales, due either to natural or anthropogenic sources of isolation and low rates of dispersal. In this study, we used molecular approaches to describe the unique population structure of brook trout inhabiting the Shavers Fork watershed, located in eastern West Virginia, and contrast it to nearby populations in tributaries of the upper Greenbrier River and North Fork South Branch Potomac Rivers. Bayesian and maximum likelihood clustering methods identified minimal population structuring among 14 collections of brook trout from throughout the mainstem and tributaries of Shavers Fork, highlighting the role of the cold-water mainstem for connectivity and high rates of effective migration among tributaries. In contrast, the Potomac and Greenbrier River collections displayed distinct levels of population differentiation among tributaries, presumably resulting from tributary isolation by warm-water mainstems. Our results highlight the importance of protecting and restoring cold-water mainstem habitats as part of region-wide brook trout conservation efforts. In addition, our results from Shavers Fork provide a contrast to previous genetic studies that characterize Appalachian brook trout as fragmented isolates rather than well-mixed populations. Additional study is needed to determine whether the existence of brook trout as genetically similar populations among tributaries is truly unique and whether connectivity among brook trout populations can potentially be restored within other central Appalachian watersheds.
Defining Primary Care Shortage Areas: Do GIS-based Measures Yield Different Results?
Daly, Michael R; Mellor, Jennifer M; Millones, Marco
2018-02-12
To examine whether geographic information systems (GIS)-based physician-to-population ratios (PPRs) yield determinations of geographic primary care shortage areas that differ from those based on bounded-area PPRs like those used in the Health Professional Shortage Area (HPSA) designation process. We used geocoded data on primary care physician (PCP) locations and census block population counts from 1 US state to construct 2 shortage area indicators. The first is a bounded-area shortage indicator defined without GIS methods; the second is a GIS-based measure that measures the populations' spatial proximity to PCP locations. We examined agreement and disagreement between bounded shortage areas and GIS-based shortage areas. Bounded shortage area indicators and GIS-based shortage area indicators agree for the census blocks where the vast majority of our study populations reside. Specifically, 95% and 98% of the populations in our full and urban samples, respectively, reside in census blocks where the 2 indicators agree. Although agreement is generally high in rural areas (ie, 87% of the rural population reside in census blocks where the 2 indicators agree), agreement is significantly lower compared to urban areas. One source of disagreement suggests that bounded-area measures may "overlook" some shortages in rural areas; however, other aspects of the HPSA designation process likely mitigate this concern. Another source of disagreement arises from the border-crossing problem, and it is more prevalent. The GIS-based PPRs we employed would yield shortage area determinations that are similar to those based on bounded-area PPRs defined for Primary Care Service Areas. Disagreement rates were lower than previous studies have found. © 2018 National Rural Health Association.
Dutch population specific sex estimation formulae using the proximal femur.
Colman, K L; Janssen, M C L; Stull, K E; van Rijn, R R; Oostra, R J; de Boer, H H; van der Merwe, A E
2018-05-01
Sex estimation techniques are frequently applied in forensic anthropological analyses of unidentified human skeletal remains. While morphological sex estimation methods are able to endure population differences, the classification accuracy of metric sex estimation methods are population-specific. No metric sex estimation method currently exists for the Dutch population. The purpose of this study is to create Dutch population specific sex estimation formulae by means of osteometric analyses of the proximal femur. Since the Netherlands lacks a representative contemporary skeletal reference population, 2D plane reconstructions, derived from clinical computed tomography (CT) data, were used as an alternative source for a representative reference sample. The first part of this study assesses the intra- and inter-observer error, or reliability, of twelve measurements of the proximal femur. The technical error of measurement (TEM) and relative TEM (%TEM) were calculated using 26 dry adult femora. In addition, the agreement, or accuracy, between the dry bone and CT-based measurements was determined by percent agreement. Only reliable and accurate measurements were retained for the logistic regression sex estimation formulae; a training set (n=86) was used to create the models while an independent testing set (n=28) was used to validate the models. Due to high levels of multicollinearity, only single variable models were created. Cross-validated classification accuracies ranged from 86% to 92%. The high cross-validated classification accuracies indicate that the developed formulae can contribute to the biological profile and specifically in sex estimation of unidentified human skeletal remains in the Netherlands. Furthermore, the results indicate that clinical CT data can be a valuable alternative source of data when representative skeletal collections are unavailable. Copyright © 2017 Elsevier B.V. All rights reserved.