Dancing to her own beat: honey bee foragers communicate via individually calibrated waggle dances.

PubMed

Schürch, Roger; Ratnieks, Francis L W; Samuelson, Elizabeth E W; Couvillon, Margaret J

2016-05-01

Communication signals often vary between individuals, even when one expects selection to favour accuracy and precision, such as the honey bee waggle dance, where foragers communicate to nestmates the direction and distance to a resource. Although many studies have examined intra-dance variation, or the variation within a dance, less is known about inter-dance variation, or the variation between dances. This is particularly true for distance communication. Here, we trained individually marked bees from three colonies to forage at feeders of known distances and monitored their dances to determine individual communication variation. We found that each honey bee possesses her own calibration: individual duration-distance calibrations varied significantly in both slopes and intercepts. The variation may incur a cost for communication, such that a dancer and recruit may misunderstand the communicated distance by as much as 50%. Future work is needed to understand better the mechanisms and consequences of individual variation in communication. © 2016. Published by The Company of Biologists Ltd.

Zebra Finch Song Phonology and Syntactical Structure across Populations and Continents-A Computational Comparison.

PubMed

Lachlan, Robert F; van Heijningen, Caroline A A; Ter Haar, Sita M; Ten Cate, Carel

2016-01-01

Learned bird songs are often characterized by a high degree of variation between individuals and sometimes between populations, while at the same time maintaining species specificity. The evolution of such songs depends on the balance between plasticity and constraints. Captive populations provide an opportunity to examine signal variation and differentiation in detail, so we analyzed adult male zebra finch (Taeniopygia guttata) songs recorded from 13 populations across the world, including one sample of songs from wild-caught males in their native Australia. Cluster analysis suggested some, albeit limited, evidence that zebra finch song units belonged to universal, species-wide categories, linked to restrictions in vocal production and non-song parts of the vocal repertoire. Across populations, songs also showed some syntactical structure, although any song unit could be placed anywhere within the song. On the other hand, there was a statistically significant differentiation between populations, but the effect size was very small, and its communicative significance dubious. Our results suggest that variation in zebra finch songs within a population is largely determined by species-wide constraints rather than population-specific features. Although captive zebra finch populations have been sufficiently isolated to allow them to genetically diverge, there does not appear to have been any divergence in the genetically determined constraints that underlie song learning. Perhaps more surprising is the lack of locally diverged cultural traditions. Zebra finches serve as an example of a system where frequent learning errors may rapidly create within-population diversity, within broad phonological and syntactical constraints, and prevent the formation of long-term cultural traditions that allow populations to diverge.

Population-level preferences for primary care physicians' characteristics in Japan: a structural equation modeling.

PubMed

Takahashi, Osamu; Ohde, Sachiko; Jacobs, Joshua L; Tokuda, Yasuharu; Yanai, Haruo; Okubo, Tomoya; Shimbo, Takuro; Fukuhara, Shunichi; Hinohara, Shigeaki; Fukui, Tsuguya

2010-01-01

Primary care has potential to play a role for improving the patient care in Japanese health care system; however, little information is available about how patients perceive the roles of primary care physicians (PCPs) within the Japanese health care system. We aimed to assess population-level preferences for PCPs and investigated the extent to which preferences vary in relation to different population groups in Japan. Data were extracted from a cross-sectional questionnaire survey in October 2003. An 18-item questionnaire was used to measure the preferences for PCPs. Exploratory factor analysis was performed to identify latent factors, while confirmatory factor analysis was used to evaluate the fit of the structure using structural equation modeling (SEM). Nationally representative sample of the adult Japanese general population was chosen by controlling for age, sex, and the size of cities. A total of 2,453 adults>or=18-years-old were analyzed. SEM provided a 4-factor structural model of the population-level preference for PCPs, such as clinical competence (path coefficient (pc)=0.72), gate-keeping (pc=0.64), communication with patients or specialists (pc=0.49) and high education (pc=0.25) and demonstrated the best goodness-of-fit. Those who were middle aged, have a high family income, and a high level of education, placed more importance on gate-keeping characteristics, and the rural residents emphasized communication rather than clinical competence. Our results indicate that the preferences for PCPs are divided into four main factors and underscore the variation among preferences according to different population groups, such as age, socioeconomic and educational status, and places of living. These variations should be considered to improve the primary care system in Japan.

Dissolved organic carbon and unimodal variation in sexual signal coloration in mosquitofish: a role for light limitation?

PubMed Central

Layman, Craig A.

2017-01-01

Natural selection plays an important role in the evolution of sexual communication systems. Here, we assess the effect of two well-known selection agents, transmission environment and predation, on interpopulation variation in sexual signals. Our model system is a series of 21 populations of Bahamian mosquitofish subjected to independent variation in optical conditions and predation risk. We show that optically diverse environments, caused by locally variable dissolved organic carbon concentrations, rather than spatial variation in predation, drove divergence in fin coloration (fin redness). We found a unimodal pattern of phenotypic variation along the optical gradient indicating a threshold-type response of visual signals to broad variation in optical conditions. We discuss evolutionary and ecological mechanisms that may drive such a pattern as well as the implications of non-monotonic clines for evolutionary differentiation. PMID:28381625

Dissolved organic carbon and unimodal variation in sexual signal coloration in mosquitofish: a role for light limitation?

PubMed

Giery, Sean T; Layman, Craig A

2017-04-12

Natural selection plays an important role in the evolution of sexual communication systems. Here, we assess the effect of two well-known selection agents, transmission environment and predation, on interpopulation variation in sexual signals. Our model system is a series of 21 populations of Bahamian mosquitofish subjected to independent variation in optical conditions and predation risk. We show that optically diverse environments, caused by locally variable dissolved organic carbon concentrations, rather than spatial variation in predation, drove divergence in fin coloration (fin redness). We found a unimodal pattern of phenotypic variation along the optical gradient indicating a threshold-type response of visual signals to broad variation in optical conditions. We discuss evolutionary and ecological mechanisms that may drive such a pattern as well as the implications of non-monotonic clines for evolutionary differentiation. © 2017 The Author(s).

Guyana dolphins (Sotalia guianensis) from Costa Rica emit whistles that vary with surface behaviors.

PubMed

May-Collado, Laura J

2013-10-01

Guyana dolphins show remarkable intraspecific whistle variation. This variation has been largely explained in terms of distance among populations; however, other factors such as behavior may also be important. A broadband recording system recorded the whistles of Guyana dolphins under three behavioral states. A discriminant analysis found that during social and travel events, dolphins emit whistles with high delta and minimum frequency, respectively. Whistle duration was also important in discriminating behaviors. This study indicates that behavior is an important factor contributing to whistle variation of Guyana dolphins. Understanding how dolphin whistles vary with behavioral context will advance our understanding of dolphin communication and enable appropriate comparative studies.

The Nature of Covariation between Autistic Traits and Clumsiness: A Twin Study in a General Population Sample

ERIC Educational Resources Information Center

Moruzzi, Sara; Ogliari, Anna; Ronald, Angelica; Happe, Francesca; Battaglia, Marco

2011-01-01

While social impairment, difficulties with communication, and restricted repetitive behaviors are central features of Autism Spectrum Disorders, physical clumsiness is a commonly co-occurring feature. In a sample of 398 twin pairs (aged 8-17 years) from the Italian Twin Registry we investigated the nature of the co-variation between a psychometric…

Can treefrog phylogeographical clades and species' phylogenetic topologies be recovered by bioacoustical analyses?

PubMed

Forti, Lucas Rodriguez; Lingnau, Rodrigo; Encarnação, Lais Carvalho; Bertoluci, Jaime; Toledo, Luís Felipe

2017-01-01

Phenotypic traits, such as the frog advertisement call, are generally correlated with interspecific genetic variation, and, as a consequence of strong sexual selection, these behaviors may carry a phylogenetic signal. However, variation in acoustic traits is not always correlated with genetic differences between populations (intraspecific variation); phenotypic plasticity and environmental variables may explain part of such variation. For example, local processes can affect acoustic properties in different lineages due to differences in physical structure, climatic conditions, and biotic interactions, particularly when populations are isolated. However, acoustic traits can be used to test phylogenetic hypotheses. We analyzed the advertisement calls of Dendropsophus elegans males from 18 sites and compared them with those of four closely related congeneric species, in order to test for differences between inter and intraspecific variation. We analyzed 451 calls of 45 males of these five species. Because males from distant sites were grouped together without population congruence, differences found in advertisement calls among individuals were not correlated with phylogeographical clades. Phylogenetic and cluster analyses of the D. elegans clades and those of closely related species grouped all five species into the same topology, as reported by previous molecular and morphological phylogenies. However, the topology of the D. elegans phylogeographical clades did not match the topology previously reported. Acoustic communication in D. elegans seems to be conserved among populations, and the phylogeographical history of the species does not explain the variation among lineages in call properties, despite some congruent phylogenetic signals evident at the species level. Based on molecular clocks retrieved from the literature, it seems that more than 6.5 million years of divergence (late Miocene) are necessary to allow significant changes to occur in the acoustic properties of these treefrog calls, making it possible to recover their phylogenetic history only based on acoustic evidence.

Wing morphometrics of Aedes (Ochlerotatus) albifasciatus (Macquart, 1838) (Diptera: Culicidae) from different climatic regions of Argentina.

PubMed

Garzón, Maximiliano J; Schweigmann, Nicolás

2018-05-16

Gene flow restrictions between populations of Aedes albifasciatus, the vector of Western equine encephalitis and Dirophilaria immitis, have been described in the central region of Argentina. Genetic and eco-physiological variations usually result in local forms reflecting the climatic regions. Mosquito wings and their different parts have ecological functions in flight and communication. Therefore, wing shape could be considered an aspect of sexual dimorphism, and its eco-physiological responses can be expressed as morphological changes induced by the environment. To compare the geographical and sexual variations with respect to wing shape and size in two Ae. albifasciatus populations from contrasting climates of Argentina (temperate: Buenos Aires, and the arid steppe of Patagonia: Sarmiento), the wings of adults reared in thermal trays at different constant temperatures (10-29 °C) were analyzed. The wing size of Ae. albifasciatus showed inverse linear relationships with the rearing thermal condition and higher slope for Buenos Aires. In the cool range (10-17 °C), geographical size variations responded to the converse Bergmann's rule, where Buenos Aires individuals were larger than those from Sarmiento. Sexual shape dimorphism occurred in both populations while geographical variation in shape was observed in both sexes. Buenos Aires individuals showed greater response sensitivity with respect to the size-temperature relation than those from Sarmiento. The converse Bergmann's rule in size variation could be due to a higher development rate in Sarmiento to produce more cohorts in the limited favorable season. The shape could be more relevant with respect to the size in the study of population structures due to the size being more liable to vary due to changes in the environment. The geographical variations with respect to morphology could be favored by the isolation between populations and adaptations to the environmental conditions. Our results demonstrate that the shape and size of wing provide useful phenotypic information for studies related to sexual and environmental adaptations.

Unmet needs of children with special health care needs in a specialized day school setting.

PubMed

Aruda, Mary M; Kelly, Mary; Newinsky, Karina

2011-06-01

Children with Special Health Care Needs (CSHCN) represent a significant component of the pediatric population. They often present to schools with multiple and increasingly complex health issues, including medical technology dependency. Their daily variation in health status requires close monitoring and communication among caregivers. Limited research exists regarding parental concerns and communication between health providers, schools, and families. This study identifies the concerns of parents with CSHCN families, including satisfaction with communication between medical providers and schools. Parents completed a survey adapted from the American Academy of Pediatrics (AAP). Analysis of data indicated a high utilization of primary care services but highlighted persistent difficulty accessing services. This study demonstrates families have basic unmet needs in attaining services, including respite and palliative care; indicated an interest in improved communication and coordination of health information between schools and their primary health care providers; and expressed interest in augmenting school health services.

Spatial heterogeneity of climate change as an experiential basis for skepticism

PubMed Central

Kaufmann, Robert K.; Mann, Michael L.; Gopal, Sucharita; Liederman, Jackie A.; Howe, Peter D.; Pretis, Felix; Gilmore, Michelle

2017-01-01

We postulate that skepticism about climate change is partially caused by the spatial heterogeneity of climate change, which exposes experiential learners to climate heuristics that differ from the global average. This hypothesis is tested by formalizing an index that measures local changes in climate using station data and comparing this index with survey-based model estimates of county-level opinion about whether global warming is happening. Results indicate that more stations exhibit cooling and warming than predicted by random chance and that spatial variations in these changes can account for spatial variations in the percentage of the population that believes that “global warming is happening.” This effect is diminished in areas that have experienced more record low temperatures than record highs since 2005. Together, these results suggest that skepticism about climate change is driven partially by personal experiences; an accurate heuristic for local changes in climate identifies obstacles to communicating ongoing changes in climate to the public and how these communications might be improved. PMID:27994143

Spatial heterogeneity of climate change as an experiential basis for skepticism.

PubMed

Kaufmann, Robert K; Mann, Michael L; Gopal, Sucharita; Liederman, Jackie A; Howe, Peter D; Pretis, Felix; Tang, Xiaojing; Gilmore, Michelle

2017-01-03

We postulate that skepticism about climate change is partially caused by the spatial heterogeneity of climate change, which exposes experiential learners to climate heuristics that differ from the global average. This hypothesis is tested by formalizing an index that measures local changes in climate using station data and comparing this index with survey-based model estimates of county-level opinion about whether global warming is happening. Results indicate that more stations exhibit cooling and warming than predicted by random chance and that spatial variations in these changes can account for spatial variations in the percentage of the population that believes that "global warming is happening." This effect is diminished in areas that have experienced more record low temperatures than record highs since 2005. Together, these results suggest that skepticism about climate change is driven partially by personal experiences; an accurate heuristic for local changes in climate identifies obstacles to communicating ongoing changes in climate to the public and how these communications might be improved.

The response to selection for broad male response to female sex pheromone and its implications for divergence in close-range mating behavior in the European corn borer moth, Ostrinia nubilalis.

PubMed

Droney, David C; Musto, Callie J; Mancuso, Katie; Roelofs, Wendell L; Linn, Charles E

2012-12-01

Coordinated sexual communication systems, seen in many species of moths, are hypothesized to be under strong stabilizing natural selection. Stabilized communication systems should be resistant to change, but there are examples of species/populations that show great diversification. A possible solution is that it is directional sexual selection on variation in male response that drives evolution. We tested a component of this model by asking whether 'rare' males (ca. 5 % of all males in a population) of the European corn borer moth (ECB), Ostrinia nubilalis, that respond to the sex pheromones of both ECB and a different Ostrinia species (O. furnacalis, the Asian corn borer, ACB), might play an important role in diversification. We specifically tested, via artificial selection, whether this broad male response has an evolvable genetic component. We increased the frequency of broad male response from 5 to 70 % in 19 generations, showing that broad-responding males could be important for the evolution of novel communication systems in ECB. We did not find a broader range of mating acceptance of broad males by females of the base population, however, suggesting that broad response would be unlikely to increase in frequency without the involvement of other factors. However, we found that ECB selection-line females accepted a broader range of courting males, including those of ACB, than did females of the base population. Thus, a genetic correlation exists between broad, long-range response to female sex pheromone and the breadth of female acceptance of males at close range. These results are discussed in the context of evolution of novel communication systems in Ostrinia.

Can treefrog phylogeographical clades and species’ phylogenetic topologies be recovered by bioacoustical analyses?

PubMed Central

Forti, Lucas Rodriguez; Lingnau, Rodrigo; Encarnação, Lais Carvalho; Bertoluci, Jaime; Toledo, Luís Felipe

2017-01-01

Phenotypic traits, such as the frog advertisement call, are generally correlated with interspecific genetic variation, and, as a consequence of strong sexual selection, these behaviors may carry a phylogenetic signal. However, variation in acoustic traits is not always correlated with genetic differences between populations (intraspecific variation); phenotypic plasticity and environmental variables may explain part of such variation. For example, local processes can affect acoustic properties in different lineages due to differences in physical structure, climatic conditions, and biotic interactions, particularly when populations are isolated. However, acoustic traits can be used to test phylogenetic hypotheses. We analyzed the advertisement calls of Dendropsophus elegans males from 18 sites and compared them with those of four closely related congeneric species, in order to test for differences between inter and intraspecific variation. We analyzed 451 calls of 45 males of these five species. Because males from distant sites were grouped together without population congruence, differences found in advertisement calls among individuals were not correlated with phylogeographical clades. Phylogenetic and cluster analyses of the D. elegans clades and those of closely related species grouped all five species into the same topology, as reported by previous molecular and morphological phylogenies. However, the topology of the D. elegans phylogeographical clades did not match the topology previously reported. Acoustic communication in D. elegans seems to be conserved among populations, and the phylogeographical history of the species does not explain the variation among lineages in call properties, despite some congruent phylogenetic signals evident at the species level. Based on molecular clocks retrieved from the literature, it seems that more than 6.5 million years of divergence (late Miocene) are necessary to allow significant changes to occur in the acoustic properties of these treefrog calls, making it possible to recover their phylogenetic history only based on acoustic evidence. PMID:28235089

A study of worldwide communications markets: The relationship between federally sponsored research and development and competitiveness of US industry in this market

NASA Technical Reports Server (NTRS)

1977-01-01

Many factors have been reviewed in an attempt to seek criteria for the establishment of regions or nations as potential customers for space communication systems. These include economic measures, demographic distributions, topographic variations, physical size, national dispersion, telephones available, investment credit viability, and the general level of technology within the population. A major consideration is the fact that essentially all nations are subject to significant financial constraints. Consequently, some form of national investment priorities becomes necessary, and these priorities are generally perceived differently according to the factors mentioned above and also according to the personalities and interests of each nation's decision makers.

Lack of phonotactic preferences of female frogs and its consequences for signal evolution.

PubMed

Velásquez, Nelson A; Valdés, Jose Luis; Vásquez, Rodrigo A; Penna, Mario

2015-09-01

Sexual selection is one of the main evolutionary forces that drive signal evolution. In previous studies, we have found out that males of Pleurodema thaul, a frog with an extensive latitudinal distribution in Chile, emits advertisement calls that show remarkable variation among populations. In addition, this variation is related to intense inter-male acoustic competition (intra-sexual selection) occurring within each population. However, the extent to which female preferences contribute to the signal divergence observed is unclear. To study the responsiveness of females in each population, we stimulated females with synthetic calls designed with the acoustic structure of their own population and subsequently responsive females were subjected to a two-choice experiment, where they were stimulated with synthetic calls of their own population versus a call of a foreign population. Females do not show phonotactic preferences for calls of their own or foreign populations as measured with both linear and circular variables. The lack of phonotactic preferences suggests an absence of participation of inter-sexual selection processes in the divergence of the acoustic signals of P. thaul, highlighting the importance of intra-sexual selection for the evolution of these signals. These results concur with studies in other vertebrates emphasizing the relevance of interactions among males for the evolution of acoustic communication systems. Copyright © 2015. Published by Elsevier B.V.

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

PubMed

Ramsay, Michèle

2012-08-31

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

Language Variation and Limits to Communication. Technical Report No. 3.

ERIC Educational Resources Information Center

Simons, Gary Francis

Strategies are developed for understanding how language variation limits communication. Methods of measuring communication are discussed, including an intelligibility measure used in the Solomon Islands. The analysis of data gathered using communication measurement is discussed. The result of the analysis is a determination of the number of…

Structure and content of chronic kidney disease information on the World Wide Web: barriers to public understanding of a pandemic.

PubMed

Calderón, José Luis; Zadshir, Ashraf; Norris, Keith

2004-10-01

Chronic kidney disease (CKD) is a pandemic and the need to inform those at risk has never been more important. The World Wide Web (WWW) is no w considered a key source of health information, but the quality and utility of this information has been challenged. In this article, we assess structural, content, and linguistic barriers to accessed CKD information and discuss the implications of limited Internet access to communicating health. Technical (number of hyperlinks), content (number of six core CKD and risk factor information domains included), and linguistic (readability and variation in readability) barriers were assessed for websites offered by 12 kidney disease associations. The Flesch Reading Ease Index method was used to estimate readability scores, and variation in the readability of information was assessed. Eleven websites met inclusion criteria. Six of 11 websites provided information in all 6 domains of CKD information. A mean of 4 hyperlinks (range 3-5) was clicked before CKD information was available and a mean of 6 hyperlinks (range 4-12) was clicked to access all available CKD information. Mean readability scores for all six domains of CKD information exceeded national average literacy skills and far exceeded the 5th grade level readability desired for informing vulnerable populations. Information about CKD and diabetes consistently had higher readability scores. The WWW currently has little utility for informing populations at greatest risk for CKD. Barriers to accessing CKD information on the WWW are socioeconomic, technical, and linguistic. Having lower socioeconomic status, less access to computers and the WWW, multiple website hyperlinks, incomplete information, difficult readability, and significant variation in readability of CKD information on the WWW are social, structural, and content barriers to communicating CKD information. This may contribute to the growing epidemics of diminished public understanding about CKD, and disparities in CKD health status experienced by racial/ethnic minority populations globally.

Cognitive-behavioral phenotypes of Williams syndrome are associated with genetic variation in the GTF2I gene, in a healthy population.

PubMed

Crespi, Bernard J; Hurd, Peter L

2014-11-28

Individuals with Williams syndrome, a neurogenetic condition caused by deletion of a set of genes at chromosomal location 7q11.23, exhibit a remarkable suite of traits including hypersociality with high, nonselective friendliness and low social anxiety, expressive language relatively well-developed but under-developed social-communication skills overall, and reduced visual-spatial abilities. Deletions and duplications of the Williams-syndrome region have also been associated with autism, and with schizophrenia, two disorders centrally involving social cognition. Several lines of evidence have linked the gene GTF2I (General Transcription Factor IIi) with the social phenotypes of Williams syndrome, but a role for this gene in sociality within healthy populations has yet to be investigated. We genotyped a large set of healthy individuals for two single-nucleotide polymorphisms in the GTF2I gene that have recently been significantly associated with autism, and thus apparently exhibit functional effects on autism-related social phenotypes. GTF2I genotypes for these SNPs showed highly significant association with low social anxiety combined with reduced social-communication abilities, which represents a metric of the Williams-syndrome cognitive profile as described from previous studies. These findings implicate the GTF2I gene in the neurogenetic basis of social communication and social anxiety, both in Williams syndrome and among individuals in healthy populations.

FOXP2 variation in great ape populations offers insight into the evolution of communication skills.

PubMed

Staes, Nicky; Sherwood, Chet C; Wright, Katharine; de Manuel, Marc; Guevara, Elaine E; Marques-Bonet, Tomas; Krützen, Michael; Massiah, Michael; Hopkins, William D; Ely, John J; Bradley, Brenda J

2017-12-04

The gene coding for the forkhead box protein P2 (FOXP2) is associated with human language disorders. Evolutionary changes in this gene are hypothesized to have contributed to the emergence of speech and language in the human lineage. Although FOXP2 is highly conserved across most mammals, humans differ at two functional amino acid substitutions from chimpanzees, bonobos and gorillas, with an additional fixed substitution found in orangutans. However, FOXP2 has been characterized in only a small number of apes and no publication to date has examined the degree of natural variation in large samples of unrelated great apes. Here, we analyzed the genetic variation in the FOXP2 coding sequence in 63 chimpanzees, 11 bonobos, 48 gorillas, 37 orangutans and 2 gibbons and observed undescribed variation in great apes. We identified two variable polyglutamine microsatellites in chimpanzees and orangutans and found three nonsynonymous single nucleotide polymorphisms, one in chimpanzees, one in gorillas and one in orangutans with derived allele frequencies of 0.01, 0.26 and 0.29, respectively. Structural and functional protein modeling indicate a biochemical effect of the substitution in orangutans, and because of its presence solely in the Sumatran orangutan species, the mutation may be associated with reported population differences in vocalizations.

Geographical variation in sound production in the anemonefish Amphiprion akallopisos.

PubMed

Parmentier, E; Lagardère, J P; Vandewalle, P; Fine, M L

2005-08-22

Because of pelagic-larval dispersal, coral-reef fishes are distributed widely with minimal genetic differentiation between populations. Amphiprion akallopisos, a clownfish that uses sound production to defend its anemone territory, has a wide but disjunct distribution in the Indian Ocean. We compared sounds produced by these fishes from populations in Madagascar and Indonesia, a distance of 6500 km. Differentiation of agonistic calls into distinct types indicates a complexity not previously recorded in fishes' acoustic communication. Moreover, various acoustic parameters, including peak frequency, pulse duration, number of peaks per pulse, differed between the two populations. The geographic comparison is the first to demonstrate 'dialects' in a marine fish species, and these differences in sound parameters suggest genetic divergence between these two populations. These results highlight the possible approach for investigating the role of sounds in fish behaviour in reproductive divergence and speciation.

Intervention strategies to reduce the burden of non-communicable diseases in Mexico: cost effectiveness analysis

PubMed Central

Carvalho, Natalie; Gutiérrez-Delgado, Cristina; Orozco, Ricardo; Mancuso, Anna; Hogan, Daniel R; Lee, Diana; Murakami, Yuki; Sridharan, Lakshmi; Medina-Mora, María Elena; González-Pier, Eduardo

2012-01-01

Objective To inform decision making regarding intervention strategies against non-communicable diseases in Mexico, in the context of health reform. Design Cost effectiveness analysis based on epidemiological modelling. Interventions 101 intervention strategies relating to nine major clusters of non-communicable disease: depression, heavy alcohol use, tobacco use, cataracts, breast cancer, cervical cancer, chronic obstructive pulmonary disease, cardiovascular disease, and diabetes. Data sources Mexican data sources were used for most key input parameters, including administrative registries; disease burden and population estimates; household surveys; and drug price databases. These sources were supplemented as needed with estimates for Mexico from the WHO-CHOICE unit cost database or with estimates extrapolated from the published literature. Main outcome measures Population health outcomes, measured in disability adjusted life years (DALYs); costs in 2005 international dollars ($Int); and costs per DALY. Results Across 101 intervention strategies examined in this study, average yearly costs at the population level would range from around ≤$Int1m (such as for cataract surgeries) to >$Int1bn for certain strategies for primary prevention in cardiovascular disease. Wide variation also appeared in total population health benefits, from <1000 DALYs averted a year (for some components of cancer treatments or aspirin for acute ischaemic stroke) to >300 000 averted DALYs (for aggressive combinations of interventions to deal with alcohol use or cardiovascular risks). Interventions in this study spanned a wide range of average cost effectiveness ratios, differing by more than three orders of magnitude between the lowest and highest ratios. Overall, community and public health interventions such as non-personal interventions for alcohol use, tobacco use, and cardiovascular risks tended to have lower cost effectiveness ratios than many clinical interventions (of varying complexity). Even within the community and public health interventions, however, there was a 200-fold difference between the most and least cost effective strategies examined. Likewise, several clinical interventions appeared among the strategies with the lowest average cost effectiveness ratios—for example, cataract surgeries. Conclusions Wide variations in costs and effects exist within and across intervention categories. For every major disease area examined, at least some strategies provided excellent value for money, including both population based and personal interventions. PMID:22389335

Variation in hearing within a wild population of beluga whales (Delphinapterus leucas).

PubMed

Mooney, T Aran; Castellote, Manuel; Quakenbush, Lori; Hobbs, Roderick; Gaglione, Eric; Goertz, Caroline

2018-05-08

Documenting hearing abilities is vital to understanding a species' acoustic ecology and for predicting the impacts of increasing anthropogenic noise. Cetaceans use sound for essential biological functions such as foraging, navigation and communication; hearing is considered to be their primary sensory modality. Yet, we know little regarding the hearing of most, if not all, cetacean populations, which limits our understanding of their sensory ecology, population level variability and the potential impacts of increasing anthropogenic noise. We obtained audiograms (5.6-150 kHz) of 26 wild beluga whales to measure hearing thresholds during capture-release events in Bristol Bay, AK, USA, using auditory evoked potential methods. The goal was to establish the baseline population audiogram, incidences of hearing loss and general variability in wild beluga whales. In general, belugas showed sensitive hearing with low thresholds (<80 dB) from 16 to 100 kHz, and most individuals (76%) responded to at least 120 kHz. Despite belugas often showing sensitive hearing, thresholds were usually above or approached the low ambient noise levels measured in the area, suggesting that a quiet environment may be associated with hearing sensitivity and that hearing thresholds in the most sensitive animals may have been masked. Although this is just one wild population, the success of the method suggests that it should be applied to other populations and species to better assess potential differences. Bristol Bay beluga audiograms showed substantial (30-70 dB) variation among individuals; this variation increased at higher frequencies. Differences among individual belugas reflect that testing multiple individuals of a population is necessary to best describe maximum sensitivity and population variance. The results of this study quadruple the number of individual beluga whales for which audiograms have been conducted and provide the first auditory data for a population of healthy wild odontocetes. © 2018. Published by The Company of Biologists Ltd.

Single cell RNA Seq reveals dynamic paracrine control of cellular variation

PubMed Central

Shalek, Alex K.; Satija, Rahul; Shuga, Joe; Trombetta, John J.; Gennert, Dave; Lu, Diana; Chen, Peilin; Gertner, Rona S.; Gaublomme, Jellert T.; Yosef, Nir; Schwartz, Schraga; Fowler, Brian; Weaver, Suzanne; Wang, Jing; Wang, Xiaohui; Ding, Ruihua; Raychowdhury, Raktima; Friedman, Nir; Hacohen, Nir; Park, Hongkun; May, Andrew P.; Regev, Aviv

2014-01-01

High-throughput single-cell transcriptomics offers an unbiased approach for understanding the extent, basis, and function of gene expression variation between seemingly identical cells. Here, we sequence single-cell RNA-Seq libraries prepared from over 1,700 primary mouse bone marrow derived dendritic cells (DCs) spanning several experimental conditions. We find substantial variation between identically stimulated DCs, in both the fraction of cells detectably expressing a given mRNA and the transcript’s level within expressing cells. Distinct gene modules are characterized by different temporal heterogeneity profiles. In particular, a “core” module of antiviral genes is expressed very early by a few “precocious” cells, but is later activated in all cells. By stimulating cells individually in sealed microfluidic chambers, analyzing DCs from knockout mice, and modulating secretion and extracellular signaling, we show that this response is coordinated via interferon-mediated paracrine signaling. Surprisingly, preventing cell-to-cell communication also substantially reduces variability in the expression of an early-induced “peaked” inflammatory module, suggesting that paracrine signaling additionally represses part of the inflammatory program. Our study highlights the importance of cell-to-cell communication in controlling cellular heterogeneity and reveals general strategies that multicellular populations use to establish complex dynamic responses. PMID:24919153

Climate-related environmental variation in a visual signalling device: the male and female dewlap in Anolis sagrei lizards.

PubMed

Driessens, T; Baeckens, S; Balzarolo, M; Vanhooydonck, B; Huyghe, K; Van Damme, R

2017-10-01

Animals communicate using a variety of signals that differ dramatically among and within species. The astonishing dewlap diversity in anoles has attracted considerable attention in this respect. Yet, the evolutionary processes behind it remain elusive and have mostly been explored for males only. Here, we considered Anolis sagrei males and females to study signal divergence among populations. First, we assessed the degree of variation in dewlap design (size, pattern and colour) and displays by comparing 17 populations distributed across the Caribbean. Second, we assessed whether the observed dewlap diversity is associated with variation in climate-related environmental conditions. Results showed that populations differed in all dewlap characteristics, with the exception of display rate in females. We further found that males and females occurring in 'xeric' environments had a higher proportion of solid dewlaps with higher UV reflectance. In addition, lizards inhabiting 'mesic' environments had primarily marginal dewlaps showing high reflectance in red. For dewlap display, a correlation with environment was only observed in males. Our study provides evidence for a strong relationship between signal design and prevailing environmental conditions, which may result from differential selection on signal efficacy. Moreover, our study highlights the importance of including females when studying dewlaps in an evolutionary context. © 2017 European Society For Evolutionary Biology. Journal of Evolutionary Biology © 2017 European Society For Evolutionary Biology.

Bipolar disorders in the Arab world: a critical review.

PubMed

Kronfol, Ziad; Zakaria Khalil, Mostafa; Kumar, Pankaj; Suhre, Karsten; Karam, Elie; McInnis, Melvin

2015-05-01

Bipolar disorders are common psychiatric disorders that affect 1-5% of the population worldwide. Major advances in the epidemiology, pathophysiology, and treatment of the disorders have recently occurred. The majority of published reports, however, originate from the Western hemisphere, mostly Europe and the United States. There is a shortage of data from the Arab world on bipolar disorders. In an era of globalization and rapid communication, it is not clear to what extent research findings pertaining to one part of the world are by necessity applicable to other parts. Psychiatric disorders are known to be affected by the culture in which they occur, and knowledge of variations in illness presentation in different ethnic groups is also increasing. However, knowledge of variations affecting Arab populations remains quite limited. This paper provides a critical review of the literature on bipolar affective disorders in the Arab world, pointing to major gaps in knowledge and future opportunities to fill these gaps. © 2015 New York Academy of Sciences.

Environmental variability and acoustic signals: a multi-level approach in songbirds.

PubMed

Medina, Iliana; Francis, Clinton D

2012-12-23

Among songbirds, growing evidence suggests that acoustic adaptation of song traits occurs in response to habitat features. Despite extensive study, most research supporting acoustic adaptation has only considered acoustic traits averaged for species or populations, overlooking intraindividual variation of song traits, which may facilitate effective communication in heterogeneous and variable environments. Fewer studies have explicitly incorporated sexual selection, which, if strong, may favour variation across environments. Here, we evaluate the prevalence of acoustic adaptation among 44 species of songbirds by determining how environmental variability and sexual selection intensity are associated with song variability (intraindividual and intraspecific) and short-term song complexity. We show that variability in precipitation can explain short-term song complexity among taxonomically diverse songbirds, and that precipitation seasonality and the intensity of sexual selection are related to intraindividual song variation. Our results link song complexity to environmental variability, something previously found for mockingbirds (Family Mimidae). Perhaps more importantly, our results illustrate that individual variation in song traits may be shaped by both environmental variability and strength of sexual selection.

Effectiveness of the Picture Exchange Communication System as a Functional Communication Intervention for Individuals with Autism Spectrum Disorders: A Practice-Based Research Synthesis

ERIC Educational Resources Information Center

Tien, Kai-Chien

2008-01-01

This research synthesis verifies the effectiveness of the Picture Exchange Communication System (PECS) for improving the functional communication skills of individuals with autism spectrum disorders (ASD). The research synthesis was focused on the degree to which variations in PECS training are associated with variations in functional…

Geographical variation in sound production in the anemonefish Amphiprion akallopisos

PubMed Central

Parmentier, E; Lagardère, J.P; Vandewalle, P; Fine, M.L

2005-01-01

Because of pelagic-larval dispersal, coral-reef fishes are distributed widely with minimal genetic differentiation between populations. Amphiprion akallopisos, a clownfish that uses sound production to defend its anemone territory, has a wide but disjunct distribution in the Indian Ocean. We compared sounds produced by these fishes from populations in Madagascar and Indonesia, a distance of 6500 km. Differentiation of agonistic calls into distinct types indicates a complexity not previously recorded in fishes' acoustic communication. Moreover, various acoustic parameters, including peak frequency, pulse duration, number of peaks per pulse, differed between the two populations. The geographic comparison is the first to demonstrate ‘dialects’ in a marine fish species, and these differences in sound parameters suggest genetic divergence between these two populations. These results highlight the possible approach for investigating the role of sounds in fish behaviour in reproductive divergence and speciation. PMID:16087425

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

PubMed

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

2015-03-01

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

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

PubMed Central

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

2015-01-01

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

A review of population-based prevalence studies of physical activity in adults in the Asia-Pacific region

PubMed Central

2012-01-01

Background Physical activity (PA) surveillance is an important component of non-communicable disease risk factor monitoring, and occurs through national and international surveillance systems. This review identifies population PA estimates for adults in the Asia-Pacific region, and examines variation in trends and prevalence rates obtained using different PA measures. Methods Data were obtained from a MEDLINE search; World Health Organization's Global Health Infobase; Government websites and reference lists of relevant papers. Inclusion criteria included: national studies or those reporting large scale population-level data; data published from 2000 to 2010 and trend data prior; sample sizes over n = 1000, or fewer subjects in small nations. Results In total, 56 population surveys from 29 Asia-Pacific countries were identified. Data on 'sufficient physical activity' amongst adults were available from 45 studies (80%), with estimates ranging from 7% to 93% (median 62%, inter-quartile range 40%-85%). For 14 countries, estimates of 'sufficient activity' were documented in multiple surveys using different methods, with the largest variation from 18% to 92% in Nepal. Median or mean MET-minutes/day, reported in 20 studies, ranged from 6 to 1356. Serial trend data were available for 11 countries (22%), for periods spanning 2-10 years. Of these, five countries demonstrated increases in physical activity over time, four demonstrated decreases and three showed no changes. Conclusions Many countries in the Asia-Pacific region collect population-level PA data. This review highlights differences in estimates within and between countries. Some differences may be real, others due to variation in the PA questions asked and survey methods used. Use of standardized protocols and measures, and combined reporting of data are essential goals of improved international PA surveillance. PMID:22251660

Analysis of Copy Number Variation in the Abp Gene Regions of Two House Mouse Subspecies Suggests Divergence during the Gene Family Expansions

PubMed Central

Pezer, Željka; Chung, Amanda G.; Karn, Robert C.

2017-01-01

Abstract The Androgen-binding protein (Abp) gene region of the mouse genome contains 64 genes, some encoding pheromones that influence assortative mating between mice from different subspecies. Using CNVnator and quantitative PCR, we explored copy number variation in this gene family in natural populations of Mus musculus domesticus (Mmd) and Mus musculus musculus (Mmm), two subspecies of house mice that form a narrow hybrid zone in Central Europe. We found that copy number variation in the center of the Abp gene region is very common in wild Mmd, primarily representing the presence/absence of the final duplications described for the mouse genome. Clustering of Mmd individuals based on this variation did not reflect their geographical origin, suggesting no population divergence in the Abp gene cluster. However, copy number variation patterns differ substantially between Mmd and other mouse taxa. Large blocks of Abp genes are absent in Mmm, Mus musculus castaneus and an outgroup, Mus spretus, although with differences in variation and breakpoint locations. Our analysis calls into question the reliance on a reference genome for interpreting the detailed organization of genes in taxa more distant from the Mmd reference genome. The polymorphic nature of the gene family expansion in all four taxa suggests that the number of Abp genes, especially in the central gene region, is not critical to the survival and reproduction of the mouse. However, Abp haplotypes of variable length may serve as a source of raw genetic material for new signals influencing reproductive communication and thus speciation of mice. PMID:28575204

Conservation implications of anthropogenic impacts on visual communication and camouflage.

PubMed

Delhey, Kaspar; Peters, Anne

2017-02-01

Anthropogenic environmental impacts can disrupt the sensory environment of animals and affect important processes from mate choice to predator avoidance. Currently, these effects are best understood for auditory and chemosensory modalities, and recent reviews highlight their importance for conservation. We examined how anthropogenic changes to the visual environment (ambient light, transmission, and backgrounds) affect visual communication and camouflage and considered the implications of these effects for conservation. Human changes to the visual environment can increase predation risk by affecting camouflage effectiveness, lead to maladaptive patterns of mate choice, and disrupt mutualistic interactions between pollinators and plants. Implications for conservation are particularly evident for disrupted camouflage due to its tight links with survival. The conservation importance of impaired visual communication is less documented. The effects of anthropogenic changes on visual communication and camouflage may be severe when they affect critical processes such as pollination or species recognition. However, when impaired mate choice does not lead to hybridization, the conservation consequences are less clear. We suggest that the demographic effects of human impacts on visual communication and camouflage will be particularly strong when human-induced modifications to the visual environment are evolutionarily novel (i.e., very different from natural variation); affected species and populations have low levels of intraspecific (genotypic and phenotypic) variation and behavioral, sensory, or physiological plasticity; and the processes affected are directly related to survival (camouflage), species recognition, or number of offspring produced, rather than offspring quality or attractiveness. Our findings suggest that anthropogenic effects on the visual environment may be of similar importance relative to conservation as anthropogenic effects on other sensory modalities. © 2016 Society for Conservation Biology.

Variations on a theme: diversification of cuticular hydrocarbons in a clade of cactophilic Drosophila

PubMed Central

2011-01-01

Background We characterized variation and chemical composition of epicuticular hydrocarbons (CHCs) in the seven species of the Drosophila buzzatii cluster with gas chromatography/mass spectrometry. Despite the critical role of CHCs in providing resistance to desiccation and involvement in communication, such as courtship behavior, mating, and aggregation, few studies have investigated how CHC profiles evolve within and between species in a phylogenetic context. We analyzed quantitative differences in CHC profiles in populations of the D. buzzatii species cluster in order to assess the concordance of CHC differentiation with species divergence. Results Thirty-six CHC components were scored in single fly extracts with carbon chain lengths ranging from C29 to C39, including methyl-branched alkanes, n-alkenes, and alkadienes. Multivariate analysis of variance revealed that CHC amounts were significantly different among all species and canonical discriminant function (CDF) analysis resolved all species into distinct, non-overlapping groups. Significant intraspecific variation was found in different populations of D. serido suggesting that this taxon is comprised of at least two species. We summarized CHC variation using CDF analysis and mapped the first five CHC canonical variates (CVs) onto an independently derived period (per) gene + chromosome inversion + mtDNA COI gene for each sex. We found that the COI sequences were not phylogenetically informative due to introgression between some species, so only per + inversion data were used. Positive phylogenetic signal was observed mainly for CV1 when parsimony methods and the test for serial independence (TFSI) were used. These results changed when no outgroup species were included in the analysis and phylogenetic signal was then observed for female CV3 and/or CV4 and male CV4 and CV5. Finally, removal of divergent populations of D. serido significantly increased the amount of phylogenetic signal as up to four out of five CVs then displayed positive phylogenetic signal. Conclusions CHCs were conserved among species while quantitative differences in CHC profiles between populations and species were statistically significant. Most CHCs were species-, population-, and sex-specific. Mapping CHCs onto an independently derived phylogeny revealed that a significant portion of CHC variation was explained by species' systematic affinities indicating phylogenetic conservatism in the evolution of these hydrocarbon arrays, presumptive waterproofing compounds and courtship signals as in many other drosophilid species. PMID:21699713

Using geographical information systems and cartograms as a health service quality improvement tool.

PubMed

Lovett, Derryn A; Poots, Alan J; Clements, Jake T C; Green, Stuart A; Samarasundera, Edgar; Bell, Derek

2014-07-01

Disease prevalence can be spatially analysed to provide support for service implementation and health care planning, these analyses often display geographic variation. A key challenge is to communicate these results to decision makers, with variable levels of Geographic Information Systems (GIS) knowledge, in a way that represents the data and allows for comprehension. The present research describes the combination of established GIS methods and software tools to produce a novel technique of visualising disease admissions and to help prevent misinterpretation of data and less optimal decision making. The aim of this paper is to provide a tool that supports the ability of decision makers and service teams within health care settings to develop services more efficiently and better cater to the population; this tool has the advantage of information on the position of populations, the size of populations and the severity of disease. A standard choropleth of the study region, London, is used to visualise total emergency admission values for Chronic Obstructive Pulmonary Disease and bronchiectasis using ESRI's ArcGIS software. Population estimates of the Lower Super Output Areas (LSOAs) are then used with the ScapeToad cartogram software tool, with the aim of visualising geography at uniform population density. An interpolation surface, in this case ArcGIS' spline tool, allows the creation of a smooth surface over the LSOA centroids for admission values on both standard and cartogram geographies. The final product of this research is the novel Cartogram Interpolation Surface (CartIS). The method provides a series of outputs culminating in the CartIS, applying an interpolation surface to a uniform population density. The cartogram effectively equalises the population density to remove visual bias from areas with a smaller population, while maintaining contiguous borders. CartIS decreases the number of extreme positive values not present in the underlying data as can be found in interpolation surfaces. This methodology provides a technique for combining simple GIS tools to create a novel output, CartIS, in a health service context with the key aim of improving visualisation communication techniques which highlight variation in small scale geographies across large regions. CartIS more faithfully represents the data than interpolation, and visually highlights areas of extreme value more than cartograms, when either is used in isolation. Copyright © 2014 The Authors. Published by Elsevier Ltd.. All rights reserved.

NASA/DOD Aerospace Knowledge Diffusion Research Project. Paper 56: Technical Communications in Engineering and Science: The Practices Within a Government Defense Laboratory

NASA Technical Reports Server (NTRS)

VonSeggern, Marilyn; Jourdain, Janet M.; Pinelli, Thomas E.

1996-01-01

Research in recent decades has identified the varied information needs of engineers versus scientists. While most of that research looked at the differences among organizations, we surveyed engineers and scientists within a single Air Force research and development laboratory about their information gathering, usage, and production practices. The results of the Phillips Laboratory survey confirm prior assumptions about distinctions between engineering and science. Because military employees responded at a much higher rate than civilian staff, the survey also became an opportunity to profile a little-known segment of the engineer/scientist population. In addition to the effect Phillips Laboratory's stated mission may have on member engineers and scientists, other factors causing variations in technical communication and information-related activities are identified.

Variations in the quality of inpatient rehabilitation care to facilitate school re-entry and cognitive and communication function for children with TBI.

PubMed

Ennis, Stephanie K; Rivara, Frederick P; Mangione-Smith, Rita; Konodi, Mark A; Mackenzie, Ellen J; Jaffe, Kenneth M

2013-01-01

To examine variations in processes of paediatric inpatient rehabilitation care related to school re-entry and management of cognitive and communication impairments after traumatic brain injury. Retrospective cohort study. Adherence to care processes recommended for children (aged 0-17) with moderate-to-severe traumatic brain injury and admitted for inpatient rehabilitation was assessed. Quality-of-care indicators for processes supporting school re-entry and cognitive and communication rehabilitation were applied to measure variations in care delivered to 174 children across nine facilities using medical record review. Adherence rates (the number of times recommended care was delivered or attempted divided by the number of times care was indicated) were calculated, revealing substantial variations in care within and between facilities. Overall, children received 51.3% (95% CI = 31.9-70.7) and 72.3% (95% CI = 61.1-83.5), of the care recommended for school re-entry and cognitive and communication rehabilitation, respectively. Substantial variations exist in the delivery of paediatric inpatient rehabilitation care processes for managing school re-entry and cognitive and communication impairments after traumatic brain injury. Measures of association of these care processes with patient outcomes are necessary. Reduction in this variation is essential to improving quality of care.

Ethnic variation in cancer patients’ ratings of information provision, communication and overall care

PubMed Central

Trenchard, Lorna; Mc Grath-Lone, Louise; Ward, Helen

2016-01-01

ABSTRACT Objective. Ethnic inequalities in cancer patient experience exist but variation within broad ethnic categories is under-explored. This study aimed to describe variation by ethnic sub-category in experiences of information provision and communication (key domains of patient experience) using National Cancer Patient Experience Survey (NCPES) data. Design. The NCPES 2012–2013 contained responses from 68,737 cancer patients treated at 155 NHS Trusts in England. Multivariate logistic regression was used to investigate associations between ethnicity and patients’ ratings of overall care, information provision and communication. Results. Variation by and within broad ethnic categories was evident. Non-White patients (particularly Asian patients (ORadj:0.78; 95%CI:0.67-0.90, p=0.001)) were less likely than White patients to receive an understandable explanation of treatment side effects. Among Asian patients, those of Bangladeshi ethnicity were least likely to receive an understandable explanation. Conclusions. Effective communication and information provision are important to ensure patients are well informed, receive the best possible care and have a positive patient experience. However, ethnic inequalities exist in cancer patients’ experiences of information provision and communication with variation evident both between and within broad ethnic categories. Further work to understand the causes of this variation is required to address ethnic inequalities at practice and policy level. PMID:26853061

Ethnic variation in cancer patients' ratings of information provision, communication and overall care.

PubMed

Trenchard, Lorna; Mc Grath-Lone, Louise; Ward, Helen

2016-10-01

Ethnic inequalities in cancer patient experience exist but variation within broad ethnic categories is under-explored. This study aimed to describe variation by ethnic sub-category in experiences of information provision and communication (key domains of patient experience) using National Cancer Patient Experience Survey (NCPES) data. The NCPES 2012-2013 contained responses from 68,737 cancer patients treated at 155 NHS Trusts in England. Multivariate logistic regression was used to investigate associations between ethnicity and patients' ratings of overall care, information provision and communication. Variation by and within broad ethnic categories was evident. Non-White patients (particularly Asian patients (ORadj:0.78; 95%CI:0.67-0.90, p=0.001)) were less likely than White patients to receive an understandable explanation of treatment side effects. Among Asian patients, those of Bangladeshi ethnicity were least likely to receive an understandable explanation. Effective communication and information provision are important to ensure patients are well informed, receive the best possible care and have a positive patient experience. However, ethnic inequalities exist in cancer patients' experiences of information provision and communication with variation evident both between and within broad ethnic categories. Further work to understand the causes of this variation is required to address ethnic inequalities at practice and policy level.

[Disability due to mental illness: social security benefits in Brazil 2008-2011].

PubMed

Silva Junior, João Silvestre da; Fischer, Frida Marina

2014-02-01

This communication aimed to analyze the profile variation of disability benefits due to mental disorders. Secondary data published by Brazilian Social Security between 2008 and 2011 were evaluated. Mean annual variation rates over the period were calculated for the economically active population, as were the number insured, paid out overall sickness benefits and for mental and behavioral disorders. Mental disorders are the third most common reason for disability benefits. There was an average annual increase of 0.3% in new benefit claims, with a 2.5% fall in mean annual incidence. Work-related disease was identified in 6.2% of cases, most of it due to mood disorders. The government should use the data from the Social Security Institute to support a debate of public policies regarding mental health.

Analysis of Copy Number Variation in the Abp Gene Regions of Two House Mouse Subspecies Suggests Divergence during the Gene Family Expansions.

PubMed

Pezer, Željka; Chung, Amanda G; Karn, Robert C; Laukaitis, Christina M

2017-06-01

The Androgen-binding protein ( Abp ) gene region of the mouse genome contains 64 genes, some encoding pheromones that influence assortative mating between mice from different subspecies. Using CNVnator and quantitative PCR, we explored copy number variation in this gene family in natural populations of Mus musculus domesticus ( Mmd ) and Mus musculus musculus ( Mmm ), two subspecies of house mice that form a narrow hybrid zone in Central Europe. We found that copy number variation in the center of the Abp gene region is very common in wild Mmd , primarily representing the presence/absence of the final duplications described for the mouse genome. Clustering of Mmd individuals based on this variation did not reflect their geographical origin, suggesting no population divergence in the Abp gene cluster. However, copy number variation patterns differ substantially between Mmd and other mouse taxa. Large blocks of Abp genes are absent in Mmm , Mus musculus castaneus and an outgroup, Mus spretus , although with differences in variation and breakpoint locations. Our analysis calls into question the reliance on a reference genome for interpreting the detailed organization of genes in taxa more distant from the Mmd reference genome. The polymorphic nature of the gene family expansion in all four taxa suggests that the number of Abp genes, especially in the central gene region, is not critical to the survival and reproduction of the mouse. However, Abp haplotypes of variable length may serve as a source of raw genetic material for new signals influencing reproductive communication and thus speciation of mice. © The Author 2017. Published by Oxford University Press on behalf of the Society for Molecular Biology and Evolution.

Links between Natural Variation in the Microbiome and Host Fitness in Wild Mammals.

PubMed

Suzuki, Taichi A

2017-10-01

Recent studies in model organisms have shown that compositional variation in the microbiome can affect a variety of host phenotypes including those related to digestion, development, immunity, and behavior. Natural variation in the microbiome within and between natural populations and species may also affect host phenotypes and thus fitness in the wild. Here, I review recent evidence that compositional variation in the microbiome may affect host phenotypes and fitness in wild mammals. Studies over the last decade indicate that natural variation in the mammalian microbiome may be important in the assistance of energy uptake from different diet types, detoxification of plant secondary compounds, protection from pathogens, chemical communication, and behavior. I discuss the importance of combining both field observations and manipulative experiments in a single system to fully characterize the functions and fitness effects of the microbiome. Finally, I discuss the evolutionary consequences of mammal-microbiome associations by proposing a framework to test how natural selection on hosts is mediated by the microbiome. © The Author 2017. Published by Oxford University Press on behalf of the Society for Integrative and Comparative Biology. All rights reserved. For permissions please email: journals.permissions@oup.com.

Strategic use of communication to market cancer prevention and control to vulnerable populations.

PubMed

Kreps, Gary L

2008-01-01

There are significant challenges to communicating relevant cancer prevention and control information to health care consumers due both to the complexities of the health information to be communicated and the complexities of health communication, especially with vulnerable populations. The need for effective communication about cancer risks, early detection, prevention, care, and survivorship is particularly acute, yet also tremendously complex, for reaching vulnerable populations, those groups of people who are most likely to suffer significantly higher levels of morbidity and mortality from cancers than other segments of the population. These vulnerable populations, typically the poorest, lowest educated, and most disenfranchised members of modern society, are heir to serious cancer-related health disparities. Vulnerable populations often have health literacy difficulties, cultural barriers, and economic challenges to accessing and making sense of relevant health information. This paper examines these challenges to communicating relevant information to vulnerable populations and suggests strategies for effectively using different communication media for marketing cancer prevention and control to reduce health disparities and promote public health.

Propagation issues for emerging mobile and portable communications: A systems perspective

NASA Technical Reports Server (NTRS)

Golshan, Nasser

1993-01-01

The viewpoint of a system engineer regarding the format of propagation information and models suitable for the design of mobile and portable satellite communications systems for the following services: audio broadcast, two way voice, and packet data is presented. Topics covered include: propagation impairments for portable indoor reception in satellite communications systems; propagation impairments and mitigation techniques for mobile satellite communications systems; characterization of mobile satellite communications channels in the presence of roadside blockage when interleaving and FEC coding are implemented; characterization of short-term mobile satellite signal variations; and characterization of long-term signal variations.

Controlled English for Effective Communication during Coalition Operations

DTIC Science & Technology

2013-06-01

Linguistic variations and cultural differences often create unexpected challenges for effective communication and thus for Command and Control (C2...CE), and CE-based tools to improve cross- linguistic /cross-cultural communication. We will discuss various types of linguistic variations and cultural...human-computer interaction, reasoning, and explanation CE and CE-based tools can play an important role in facilitating cross- linguistic and cross

The Value of Information for Populations in Varying Environments

NASA Astrophysics Data System (ADS)

Rivoire, Olivier; Leibler, Stanislas

2011-04-01

The notion of information pervades informal descriptions of biological systems, but formal treatments face the problem of defining a quantitative measure of information rooted in a concept of fitness, which is itself an elusive notion. Here, we present a model of population dynamics where this problem is amenable to a mathematical analysis. In the limit where any information about future environmental variations is common to the members of the population, our model is equivalent to known models of financial investment. In this case, the population can be interpreted as a portfolio of financial assets and previous analyses have shown that a key quantity of Shannon's communication theory, the mutual information, sets a fundamental limit on the value of information. We show that this bound can be violated when accounting for features that are irrelevant in finance but inherent to biological systems, such as the stochasticity present at the individual level. This leads us to generalize the measures of uncertainty and information usually encountered in information theory.

Scent marking in Sunda clouded leopards (Neofelis diardi): novel observations close a key gap in understanding felid communication behaviours.

PubMed

Allen, Maximilian L; Wittmer, Heiko U; Setiawan, Endro; Jaffe, Sarah; Marshall, Andrew J

2016-10-14

Intraspecific communication is integral to the behavioural ecology of solitary carnivores, but observing and quantifying their communication behaviours in natural environments is difficult. Our systematic literature review found that basic information on scent marking is completely lacking for 23% of all felid species, and information on 21% of other felid species comes solely from one study of captive animals. Here we present results of the first systematic investigation of the scent marking behaviours of Sunda clouded leopards in the wild. Our observations using motion-triggered video cameras in Indonesian Borneo are novel for clouded leopards, and contrary to previous descriptions of their behaviour. We found that clouded leopards displayed 10 distinct communication behaviours, with olfaction, scraping, and cheek rubbing the most frequently recorded. We also showed that males make repeated visits to areas they previously used for marking and that multiple males advertise and receive information at the same sites, potentially enhancing our ability to document and monitor clouded leopard populations. The behaviours we recorded are remarkably similar to those described in other solitary felids, despite tremendous variation in the environments they inhabit, and close a key gap in understanding and interpreting communication behaviours of clouded leopards and other solitary felids.

Scent marking in Sunda clouded leopards (Neofelis diardi): novel observations close a key gap in understanding felid communication behaviours

PubMed Central

Allen, Maximilian L.; Wittmer, Heiko U.; Setiawan, Endro; Jaffe, Sarah; Marshall, Andrew J.

2016-01-01

Intraspecific communication is integral to the behavioural ecology of solitary carnivores, but observing and quantifying their communication behaviours in natural environments is difficult. Our systematic literature review found that basic information on scent marking is completely lacking for 23% of all felid species, and information on 21% of other felid species comes solely from one study of captive animals. Here we present results of the first systematic investigation of the scent marking behaviours of Sunda clouded leopards in the wild. Our observations using motion-triggered video cameras in Indonesian Borneo are novel for clouded leopards, and contrary to previous descriptions of their behaviour. We found that clouded leopards displayed 10 distinct communication behaviours, with olfaction, scraping, and cheek rubbing the most frequently recorded. We also showed that males make repeated visits to areas they previously used for marking and that multiple males advertise and receive information at the same sites, potentially enhancing our ability to document and monitor clouded leopard populations. The behaviours we recorded are remarkably similar to those described in other solitary felids, despite tremendous variation in the environments they inhabit, and close a key gap in understanding and interpreting communication behaviours of clouded leopards and other solitary felids. PMID:27739507

The mechanism of sound production in túngara frogs and its role in sexual selection and speciation.

PubMed

Ryan, Michael J; Guerra, Mónica A

2014-10-01

Sexual communication can evolve in response to sexual selection, and it can also cause behavioral reproductive isolation between populations and thus drive speciation. Anurans are an excellent system to investigate these links between behavior and evolution because we have detailed knowledge of how neural mechanisms generate behavioral preferences for calls and how these preferences then generate selection on call variation. But we know far less about the physical mechanisms of call production, especially how different laryngeal morphologies generate call variation. Here we review studies of a group of species that differ in the presence of a secondary call component that evolved under sexual selection. We discuss how the larynx produces this call component, and how laryngeal morphology generates sexual selection and can contribute to speciation. Copyright © 2014. Published by Elsevier Ltd.

Introduction of a guide to enhance risk communication among low-income and minority populations: a grassroots community engagement approach.

PubMed

Rowel, Randy; Sheikhattari, Payam; Barber, Tanyka M; Evans-Holland, Myrtle

2012-01-01

Low-income populations, especially those belonging to minority groups, are among the most vulnerable groups before, during, and after a natural disaster. One of the factors that can be attributed to their vulnerability is the ineffectiveness of traditional risk communication systems in reaching this population. Many low-income populations are distrustful of government agencies and those who typically communicate risk messages. Consequently, traditional systems are not as effective in reaching these communities. Furthermore, traditional systems have been based on the social media that the general population uses and not based on social networks of disadvantaged populations which are more important than formal channels in these communities for dissemination of information. To bridge the gap, an approach is needed that relies on trusted agencies and leaders to educate and warn low-income communities about possible public health threats. A grassroots approach can enhance the capacity of the risk communication systems to more effectively reach vulnerable populations by engaging grassroots organizations in risk communication activities. The Guide to Enhance Grassroots Risk Communication Among Low-Income Populations provides strategies and guidance that can assist agencies in upgrading their systems for risk communication by building partnerships with local community stakeholders.

Working against gravity: horizontal honeybee waggle runs have greater angular scatter than vertical waggle runs

PubMed Central

Couvillon, Margaret J.; Phillipps, Hunter L. F.; Schürch, Roger; Ratnieks, Francis L. W.

2012-01-01

The presence of noise in a communication system may be adaptive or may reflect unavoidable constraints. One communication system where these alternatives are debated is the honeybee (Apis mellifera) waggle dance. Successful foragers communicate resource locations to nest-mates by a dance comprising repeated units (waggle runs), which repetitively transmit the same distance and direction vector from the nest. Intra-dance waggle run variation occurs and has been hypothesized as a colony-level adaptation to direct recruits over an area rather than a single location. Alternatively, variation may simply be due to constraints on bees' abilities to orient waggle runs. Here, we ask whether the angle at which the bee dances on vertical comb influences waggle run variation. In particular, we determine whether horizontal dances, where gravity is not aligned with the waggle run orientation, are more variable in their directional component. We analysed 198 dances from foragers visiting natural resources and found support for our prediction. More horizontal dances have greater angular variation than dances performed close to vertical. However, there is no effect of waggle run angle on variation in the duration of waggle runs, which communicates distance. Our results weaken the hypothesis that variation is adaptive and provide novel support for the constraint hypothesis. PMID:22513277

Working against gravity: horizontal honeybee waggle runs have greater angular scatter than vertical waggle runs.

PubMed

Couvillon, Margaret J; Phillipps, Hunter L F; Schürch, Roger; Ratnieks, Francis L W

2012-08-23

The presence of noise in a communication system may be adaptive or may reflect unavoidable constraints. One communication system where these alternatives are debated is the honeybee (Apis mellifera) waggle dance. Successful foragers communicate resource locations to nest-mates by a dance comprising repeated units (waggle runs), which repetitively transmit the same distance and direction vector from the nest. Intra-dance waggle run variation occurs and has been hypothesized as a colony-level adaptation to direct recruits over an area rather than a single location. Alternatively, variation may simply be due to constraints on bees' abilities to orient waggle runs. Here, we ask whether the angle at which the bee dances on vertical comb influences waggle run variation. In particular, we determine whether horizontal dances, where gravity is not aligned with the waggle run orientation, are more variable in their directional component. We analysed 198 dances from foragers visiting natural resources and found support for our prediction. More horizontal dances have greater angular variation than dances performed close to vertical. However, there is no effect of waggle run angle on variation in the duration of waggle runs, which communicates distance. Our results weaken the hypothesis that variation is adaptive and provide novel support for the constraint hypothesis.

A meta-analysis of the social communication questionnaire: Screening for autism spectrum disorder.

PubMed

Chesnut, Steven R; Wei, Tianlan; Barnard-Brak, Lucy; Richman, David M

2017-11-01

The current meta-analysis examines the previous research on the utility of the Social Communication Questionnaire as a screening instrument for autism spectrum disorder. Previously published reports have highlighted the inconsistencies between Social Communication Questionnaire-screening results and formal autism spectrum disorder diagnoses. The variations in accuracy resulted in some researchers questioning the validity of the Social Communication Questionnaire. This study systematically examined the accuracy of the Social Communication Questionnaire as a function of the methodological decisions made by researchers screening for autism spectrum disorder over the last 15 years. Findings from this study suggest that the Social Communication Questionnaire is an acceptable screening instrument for autism spectrum disorder (area under the curve = 0.885). Variations in methodological decisions, however, greatly influenced the accuracy of the Social Communication Questionnaire in screening for autism spectrum disorder. Of these methodological variations, using the Current instead of the Lifetime version of the Social Communication Questionnaire resulted in the largest detrimental effect ( d = -3.898), followed by using the Social Communication Questionnaire with individuals younger than 4 years of age ( d = -2.924) and relying upon convenience samples ( d = -4.828 for clinical samples, -2.734 for convenience samples, and -1.422 for community samples). Directions for future research and implications for using the Social Communication Questionnaire to screen for autism spectrum disorder are discussed.

Relationship between communication skills and gross motor function in preschool-aged children with cerebral palsy.

PubMed

Coleman, Andrea; Weir, Kelly A; Ware, Robert S; Boyd, Roslyn N

2013-11-01

To explore the communication skills of children with cerebral palsy (CP) at 24 months' corrected age with reference to typically developing children, and to determine the relationship between communication ability, gross motor function, and other comorbidities associated with CP. Prospective, cross-sectional, population-based cohort study. General community. Children with CP (N=124; mean age, 24mo; functional severity on Gross Motor Function Classification System [GMFCS]: I=47, II=14, III=22, IV=19, V=22). Not applicable. Parents reported communication skills on the Communication and Symbolic Behavior Scales Developmental Profile (CSBS-DP) Infant-Toddler Checklist. Two independent physiotherapists classified motor type, distribution, and GMFCS. Data on comorbidities were obtained from parent interviews and medical records. Children with mild CP (GMFCS I/II) had mean CSBS-DP scores that were 0.5 to 0.6 SD below the mean for typically developing peers, while those with moderate-severe impairment (GMFCS III-V) were 1.4 to 2.6 SD below the mean. GMFCS was significantly associated with performance on the CSBS-DP (F=18.55, P<.001), with gross motor ability accounting for 38% of the variation in communication. Poorer communication was strongly associated with gross motor function and full-term birth. Preschool-aged children with CP, with more severe gross motor impairment, showed delayed communication, while children with mild motor impairment were less vulnerable. Term-born children had significantly poorer communication than those born prematurely. Because a portion of each gross motor functional severity level is at risk, this study reinforces the need for early monitoring of communication development for all children with CP. Copyright © 2013 American Congress of Rehabilitation Medicine. Published by Elsevier Inc. All rights reserved.

Primary goals, information-giving and men’s understanding: a qualitative study of Australian and UK doctors’ varied communication about PSA screening

PubMed Central

Pickles, Kristen; Rychetnik, Lucie; McCaffery, Kirsten; Entwistle, Vikki A

2018-01-01

Objectives (1) To characterise variation in general practitioners’ (GPs’) accounts of communicating with men about prostate cancer screening using the prostate-specific antigen (PSA) test, (2) to characterise GPs’ reasons for communicating as they do and (3) to explain why and under what conditions GP communication approaches vary. Study design and setting A grounded theory study. We interviewed 69 GPs consulting in primary care practices in Australia (n=40) and the UK (n=29). Results GPs explained their communication practices in relation to their primary goals. In Australia, three different communication goals were reported: to encourage asymptomatic men to either have a PSA test, or not test, or alternatively, to support men to make their own decision. As well as having different primary goals, GPs aimed to provide different information (from comprehensive to strongly filtered) and to support men to develop different kinds of understanding, from population-level to ‘gist’ understanding. Taking into account these three dimensions (goals, information, understanding) and building on Entwistle et al’s Consider an Offer framework, we derived four overarching approaches to communication: Be screened, Do not be screened, Analyse and choose, and As you wish. We also describe ways in which situational and relational factors influenced GPs’ preferred communication approach. Conclusion GPs’ reported approach to communicating about prostate cancer screening varies according to three dimensions—their primary goal, information provision preference and understanding sought—and in response to specific practice situations. If GP communication about PSA screening is to become more standardised in Australia, it is likely that each of these dimensions will require attention in policy and practice support interventions. PMID:29362252

Primary goals, information-giving and men's understanding: a qualitative study of Australian and UK doctors' varied communication about PSA screening.

PubMed

Pickles, Kristen; Carter, Stacy M; Rychetnik, Lucie; McCaffery, Kirsten; Entwistle, Vikki A

2018-01-23

(1) To characterise variation in general practitioners' (GPs') accounts of communicating with men about prostate cancer screening using the prostate-specific antigen (PSA) test, (2) to characterise GPs' reasons for communicating as they do and (3) to explain why and under what conditions GP communication approaches vary. A grounded theory study. We interviewed 69 GPs consulting in primary care practices in Australia (n=40) and the UK (n=29). GPs explained their communication practices in relation to their primary goals. In Australia, three different communication goals were reported: to encourage asymptomatic men to either have a PSA test, or not test, or alternatively, to support men to make their own decision. As well as having different primary goals, GPs aimed to provide different information (from comprehensive to strongly filtered) and to support men to develop different kinds of understanding, from population-level to 'gist' understanding. Taking into account these three dimensions (goals, information, understanding) and building on Entwistle et al' s Consider an Offer framework, we derived four overarching approaches to communication: Be screened , Do not be screened , Analyse and choose , and As you wish . We also describe ways in which situational and relational factors influenced GPs' preferred communication approach. GPs' reported approach to communicating about prostate cancer screening varies according to three dimensions-their primary goal, information provision preference and understanding sought-and in response to specific practice situations. If GP communication about PSA screening is to become more standardised in Australia, it is likely that each of these dimensions will require attention in policy and practice support interventions. © 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.

Brain communication in the locked-in state.

PubMed

De Massari, Daniele; Ruf, Carolin A; Furdea, Adrian; Matuz, Tamara; van der Heiden, Linda; Halder, Sebastian; Silvoni, Stefano; Birbaumer, Niels

2013-06-01

Patients in the completely locked-in state have no means of communication and they represent the target population for brain-computer interface research in the last 15 years. Although different paradigms have been tested and different physiological signals used, to date no sufficiently documented completely locked-in state patient was able to control a brain-computer interface over an extended time period. We introduce Pavlovian semantic conditioning to enable basic communication in completely locked-in state. This novel paradigm is based on semantic conditioning for online classification of neuroelectric or any other physiological signals to discriminate between covert (cognitive) 'yes' and 'no' responses. The paradigm comprised the presentation of affirmative and negative statements used as conditioned stimuli, while the unconditioned stimulus consisted of electrical stimulation of the skin paired with affirmative statements. Three patients with advanced amyotrophic lateral sclerosis participated over an extended time period, one of which was in a completely locked-in state, the other two in the locked-in state. The patients' level of vigilance was assessed through auditory oddball procedures to study the correlation between vigilance level and the classifier's performance. The average online classification accuracies of slow cortical components of electroencephalographic signals were around chance level for all the patients. The use of a non-linear classifier in the offline classification procedure resulted in a substantial improvement of the accuracy in one locked-in state patient achieving 70% correct classification. A reliable level of performance in the completely locked-in state patient was not achieved uniformly throughout the 37 sessions despite intact cognitive processing capacity, but in some sessions communication accuracies up to 70% were achieved. Paradigm modifications are proposed. Rapid drop of vigilance was detected suggesting attentional variations or variations of circadian period as important factors in brain-computer interface communication with locked-in state and completely locked-in state.

An Analysis of Communication as a Key Component in Leadership with Diverse School Populations

ERIC Educational Resources Information Center

Cagle, Jo E.; Wiley, Sandy T.

2012-01-01

"Effective Communication as an Essential Element of Leaders with Diverse School Populations" describes a problem based learning project focused on issues related to practices used by principals to address diverse school populations. The team found that communication between principals and diverse populations in schools was a challenge.…

Exploring the variation in implementation of a COPD disease management programme and its impact on health outcomes: a post hoc analysis of the RECODE cluster randomised trial.

PubMed

Boland, Melinde R S; Kruis, Annemarije L; Huygens, Simone A; Tsiachristas, Apostolos; Assendelft, Willem J J; Gussekloo, Jacobijn; Blom, Coert M G; Chavannes, Niels H; Rutten-van Mölken, Maureen P M H

2015-12-17

This study aims to (1) examine the variation in implementation of a 2-year chronic obstructive pulmonary disease (COPD) management programme called RECODE, (2) analyse the facilitators and barriers to implementation and (3) investigate the influence of this variation on health outcomes. Implementation variation among the 20 primary-care teams was measured directly using a self-developed scale and indirectly through the level of care integration as measured with the Patient Assessment of Chronic Illness Care (PACIC) and the Assessment of Chronic Illness Care (ACIC). Interviews were held to obtain detailed information regarding the facilitators and barriers to implementation. Multilevel models were used to investigate the association between variation in implementation and change in outcomes. The teams implemented, on average, eight of the 19 interventions, and the specific package of interventions varied widely. Important barriers and facilitators of implementation were (in)sufficient motivation of healthcare provider and patient, the high starting level of COPD care, the small size of the COPD population per team, the mild COPD population, practicalities of the information and communication technology (ICT) system, and hurdles in reimbursement. Level of implementation as measured with our own scale and the ACIC was not associated with health outcomes. A higher level of implementation measured with the PACIC was positively associated with improved self-management capabilities, but this association was not found for other outcomes. There was a wide variety in the implementation of RECODE, associated with barriers at individual, social, organisational and societal level. There was little association between extent of implementation and health outcomes.

Exploring the variation in implementation of a COPD disease management programme and its impact on health outcomes: a post hoc analysis of the RECODE cluster randomised trial

PubMed Central

Boland, Melinde R S; Kruis, Annemarije L; Huygens, Simone A; Tsiachristas, Apostolos; Assendelft, Willem J J; Gussekloo, Jacobijn; Blom, Coert M G; Chavannes, Niels H; Rutten-van Mölken, Maureen P M H

2015-01-01

This study aims to (1) examine the variation in implementation of a 2-year chronic obstructive pulmonary disease (COPD) management programme called RECODE, (2) analyse the facilitators and barriers to implementation and (3) investigate the influence of this variation on health outcomes. Implementation variation among the 20 primary-care teams was measured directly using a self-developed scale and indirectly through the level of care integration as measured with the Patient Assessment of Chronic Illness Care (PACIC) and the Assessment of Chronic Illness Care (ACIC). Interviews were held to obtain detailed information regarding the facilitators and barriers to implementation. Multilevel models were used to investigate the association between variation in implementation and change in outcomes. The teams implemented, on average, eight of the 19 interventions, and the specific package of interventions varied widely. Important barriers and facilitators of implementation were (in)sufficient motivation of healthcare provider and patient, the high starting level of COPD care, the small size of the COPD population per team, the mild COPD population, practicalities of the information and communication technology (ICT) system, and hurdles in reimbursement. Level of implementation as measured with our own scale and the ACIC was not associated with health outcomes. A higher level of implementation measured with the PACIC was positively associated with improved self-management capabilities, but this association was not found for other outcomes. There was a wide variety in the implementation of RECODE, associated with barriers at individual, social, organisational and societal level. There was little association between extent of implementation and health outcomes. PMID:26677770

Print information to inform decisions about mammography screening participation in 16 countries with population-based programs.

PubMed

Zapka, Jane G; Geller, Berta M; Bulliard, Jean-Luc; Fracheboud, Jacques; Sancho-Garnier, Helene; Ballard-Barbash, Rachel

2006-10-01

To profile and compare the content and presentation of written communications related to informed decision-making about mammography. Materials from 16 screening programs organized at the national or regional level were analyzed according to five major information domains suggested by the international literature. A majority of countries provided information on the program (interval, cost and quality). There was considerable variability in comprehensiveness of elements in the domains, e.g., test characteristics (false positive/negative) and pros and cons of screening. The majority noted the likelihood of recall for further tests, few commented on the risks of additional tests or finding unimportant tumors. The audit also found variation in presentation (words and pictures). Presentation of comprehensive, but balanced information on screening benefits and risks is complex and daunting. Issues such as framing effects, coupled with debate about screening efficacy are challenging to the design of effective information tools. The objective of increasing screening prevalence at the population level must be balanced with objectively presenting complete and clear information. Additional research is needed on how information (and mode of presentation) impact screening decisions. Public health officials need to articulate their objectives and review written communication according to important decision-making domains.

'Compromise' in Echolocation Calls between Different Colonies of the Intermediate Leaf-Nosed Bat (Hipposideros larvatus).

PubMed

Chen, Yi; Liu, Qi; Su, Qianqian; Sun, Yunxiao; Peng, Xingwen; He, Xiangyang; Zhang, Libiao

2016-01-01

Each animal population has its own acoustic signature which facilitates identification, communication and reproduction. The sonar signals of bats can convey social information, such as species identity and contextual information. The goal of this study was to determine whether bats adjust their echolocation call structures to mutually recognize and communicate when they encounter the bats from different colonies. We used the intermediate leaf-nosed bats (Hipposideros larvatus) as a case study to investigate the variations of echolocation calls when bats from one colony were introduced singly into the home cage of a new colony or two bats from different colonies were cohabitated together for one month. Our experiments showed that the single bat individual altered its peak frequency of echolocation calls to approach the call of new colony members and two bats from different colonies adjusted their call frequencies toward each other to a similar frequency after being chronically cohabitated. These results indicate that the 'compromise' in echolocation calls might be used to ensure effective mutual communication among bats.

‘Compromise’ in Echolocation Calls between Different Colonies of the Intermediate Leaf-Nosed Bat (Hipposideros larvatus)

PubMed Central

Chen, Yi; Liu, Qi; Su, Qianqian; Sun, Yunxiao; Peng, Xingwen; He, Xiangyang; Zhang, Libiao

2016-01-01

Each animal population has its own acoustic signature which facilitates identification, communication and reproduction. The sonar signals of bats can convey social information, such as species identity and contextual information. The goal of this study was to determine whether bats adjust their echolocation call structures to mutually recognize and communicate when they encounter the bats from different colonies. We used the intermediate leaf-nosed bats (Hipposideros larvatus) as a case study to investigate the variations of echolocation calls when bats from one colony were introduced singly into the home cage of a new colony or two bats from different colonies were cohabitated together for one month. Our experiments showed that the single bat individual altered its peak frequency of echolocation calls to approach the call of new colony members and two bats from different colonies adjusted their call frequencies toward each other to a similar frequency after being chronically cohabitated. These results indicate that the ‘compromise’ in echolocation calls might be used to ensure effective mutual communication among bats. PMID:27029005

Looking behind the bars: emerging health issues for people in prison.

PubMed

Stürup-Toft, S; O'Moore, E J; Plugge, E H

2018-03-01

There are more than 10 million people imprisoned worldwide. These individuals experience a higher burden of communicable and non-communicable disease, mental health and substance misuse problems than the general population and often come from marginalized and underserved groups in the community. Prisons offer an important opportunity for tackling health problems in a way that can deliver benefits to the individual and to the community. This paper focuses specifically on emerging health issues for prisons across the world. This paper uses sources of international data from published systematic reviews and research studies, the Ministry of Justice for England and Wales, the Prisons and Probations Ombudsmen Review and other United Kingdom government briefing papers. Deaths in custody are a key concern for the justice system as well as the health system. Suicide is the leading cause of mortality in prisons worldwide but non-communicable diseases, such as cardiovascular disease, are increasing in importance in high-income countries and are now the leading cause of mortality in prisons in England and Wales. The prison population is ageing in most high-income countries. Older people in prison typically have multiple and complex medical and social care needs including reduced mobility and personal care needs as well as poor health. Further research is needed to understand the complex relationship between sentencing patterns, the ageing prison population and deaths in custody; to model its impact on prisons and healthcare provision in the future and to determine effective and cost-effective models of care. Research into the health of prisoners is important in improving the health of prisoners but there is considerable variation in quantity and quality between countries. Recent innovations seek to address this disparity and facilitate the sharing of good practice.

Obesity, An Emerging Epidemic In Pakistan-A Review Of Evidence.

PubMed

Tanzil, Sana; Jamali, Tanzil

2016-01-01

In Pakistan, the disease pattern is facing a huge changeover from acute and communicable diseases to the non-communicable diseases. Moreover, an emerging epidemic of obesity is still under recognized in Pakistan. A detailed review and dissemination of the existing knowledge to determine the extent of burden of obesity can help understand this important public health issue. A detailed literature review was conducted through PubMed search engines, regarding obesity burden in Pakistan. The original peer reviewed research articles, reports of WHO in English language, non-government organizations reports were included in the review. "Obesity AND Pakistan" were used as a search terms. Pakistan is suffering from epidemic of obesity, affecting all age groups. Urban population, particularly women shows considerable higher burden of obesity as compared to men and women from rural population. However, among children and adolescents there is variation in prevalence of obesity. Girls from all age groups are predominantly more obese as compared to boys. Most of the studies have estimated child obesity among school going children of different age groups and need careful interpretation. Pakistan is currently suffering from an emerging epidemic of obesity. The rising burden of obesity is widespread among adults (man and women) and children. The burden of obesity is higher among females in all age groups as compare to males. Effective interventions are required at population level to prevent and control this emerging public health issue.

Genetic variation facilitates seedling establishment but not population growth rate of a perennial invader

PubMed Central

Li, Shou-Li; Vasemägi, Anti; Ramula, Satu

2016-01-01

Background and Aims Assessing the demographic consequences of genetic variation is fundamental to invasion biology. However, genetic and demographic approaches are rarely combined to explore the effects of genetic variation on invasive populations in natural environments. This study combined population genetics, demographic data and a greenhouse experiment to investigate the consequences of genetic variation for the population fitness of the perennial, invasive herb Lupinus polyphyllus. Methods Genetic and demographic data were collected from 37 L. polyphyllus populations representing different latitudes in Finland, and genetic variation was characterized based on 13 microsatellite loci. Associations between genetic variation and population size, population density, latitude and habitat were investigated. Genetic variation was then explored in relation to four fitness components (establishment, survival, growth, fecundity) measured at the population level, and the long-term population growth rate (λ). For a subset of populations genetic variation was also examined in relation to the temporal variability of λ. A further assessment was made of the role of natural selection in the observed variation of certain fitness components among populations under greenhouse conditions. Key Results It was found that genetic variation correlated positively with population size, particularly at higher latitudes, and differed among habitat types. Average seedling establishment per population increased with genetic variation in the field, but not under greenhouse conditions. Quantitative genetic divergence (QST) based on seedling establishment in the greenhouse was smaller than allelic genetic divergence (F′ST), indicating that unifying selection has a prominent role in this fitness component. Genetic variation was not associated with average survival, growth or fecundity measured at the population level, λ or its variability. Conclusions The study suggests that although genetic variation may facilitate plant invasions by increasing seedling establishment, it may not necessarily affect the long-term population growth rate. Therefore, established invasions may be able to grow equally well regardless of their genetic diversity. PMID:26420202

Population Analysis: Communicating About Anthropometry in Context

NASA Technical Reports Server (NTRS)

Thaxton, Sherry; Rajulu, Sudhakar

2009-01-01

This slide presentation reviews the importance of communications about anthropometry and population analysis in particular for the design of aerospace systems. The difficulty of providing anthropometric accomodation an entire range of the population is reviewed, and the importance of communication of the issues with human system integration is emphasized, and the analysis of population as it applies to existing human factors methodologies is a novel way to assist with the communication. The issues of space suit design and anthropometry is reviewed as an example.

Chemical composition of axillary odorants reflects social and individual attributes in rhesus macaques.

PubMed

Weiß, Brigitte M; Kücklich, Marlen; Thomsen, Ruth; Henkel, Stefanie; Jänig, Susann; Kulik, Lars; Birkemeyer, Claudia; Widdig, Anja

2018-01-01

Scents play an important role in the life of most terrestrial mammals and may transmit valuable information about conspecifics. Olfaction was long considered of low importance in Old World monkeys due to their relative reduction of olfactory structures and low incidence of scent-marking behavior but has been increasingly recognized for mediating social relationships in recent years. Yet, studies investigating the composition of their chemical cues remain scarce. In the present study, we analyzed the potential information content of chemicals present on the skin of rhesus macaques ( Macaca mulatta ). We collected axillary secretions from 60 animals of the semifree-ranging population on Cayo Santiago (Puerto Rico, USA) with precleaned cotton swabs from which the secretions were subsequently extracted and analyzed by gas chromatography-mass spectrometry. Rhesus macaque axillary odorants varied in their overall similarity and composition. This variation was attributable to differences in sex, group membership, and kinship and further appeared to reflect age and rank in parts of our sample. The compounds most strongly associated with this variation primarily comprised larger molecular weight aldehydes and steroids. Such compounds are considered to be perceivable by the primate olfactory system through close-range interactions or through breakdown into smaller molecules by bacterial fermentation. Overall, our results provide additional evidence that odors of Old World monkeys reflect a wealth of potential information about their carrier, which provides the basis for chemical communication via body odors; however, its use by conspecifics needs to be confirmed in bioassays. One prerequisite for olfactory communication is the presence of systematic variation in animal odors that is related to attributes such as age, sex, or kinship. The composition of odors has been examined in numerous mammals but, with the exception of humans, remains poorly understood in Old World monkeys and apes, taxonomic groups in which most species do not show scent-marking behavior. In the present study, we show that the composition of axillary secretions of an Old World monkey, the rhesus macaque, reflects sex, group membership, relatedness, and possibly also age and rank. This variation thus provides a basis for olfactory communication in Old World monkeys.

Novel rare variations of the oxytocin receptor (OXTR) gene in autism spectrum disorder individuals.

PubMed

Liu, Xiaoxi; Kawashima, Minae; Miyagawa, Taku; Otowa, Takeshi; Latt, Khun Zaw; Thiri, Myo; Nishida, Hisami; Sugiyama, Toshiro; Tsurusaki, Yoshinori; Matsumoto, Naomichi; Mabuchi, Akihiko; Tokunaga, Katsushi; Sasaki, Tsukasa

2015-01-01

The oxytocin receptor (OXTR) gene has been implicated as a risk gene for autism spectrum disorder (ASD)-a neurodevelopmental disorder with essential features of impairments in social communication and reciprocal interaction. The genetic associations between common variations in OXTR and ASD have been reported in multiple ethnic populations. However, little is known about the distribution of rare variations within OXTR in ASD patients. In this study, we resequenced the full length of OXTR in 105 ASD individuals using an approach that combined the power of next-generation sequencing technology, long-range PCR and DNA pooling. We demonstrated that rare variants with minor allele frequency as low as 0.05% could be reliably detected by our method. We identified 28 novel variants including potential functional variants in the intron region and one rare missense variant (R150S). We subsequently performed Sanger sequencing and validated five novel variants located in previously suggested candidate regions in ASD individuals. Further sequencing of 312 healthy subjects showed that the burden of rare variants is significantly higher in ASDs compared with healthy individuals. Our results support that the rare variation in OXTR gene might be involved in ASD.

The Non-linear Health Consequences of Living in Larger Cities.

PubMed

Rocha, Luis E C; Thorson, Anna E; Lambiotte, Renaud

2015-10-01

Urbanization promotes economy, mobility, access, and availability of resources, but on the other hand, generates higher levels of pollution, violence, crime, and mental distress. The health consequences of the agglomeration of people living close together are not fully understood. Particularly, it remains unclear how variations in the population size across cities impact the health of the population. We analyze the deviations from linearity of the scaling of several health-related quantities, such as the incidence and mortality of diseases, external causes of death, wellbeing, and health care availability, in respect to the population size of cities in Brazil, Sweden, and the USA. We find that deaths by non-communicable diseases tend to be relatively less common in larger cities, whereas the per capita incidence of infectious diseases is relatively larger for increasing population size. Healthier lifestyle and availability of medical support are disproportionally higher in larger cities. The results are connected with the optimization of human and physical resources and with the non-linear effects of social networks in larger populations. An urban advantage in terms of health is not evident, and using rates as indicators to compare cities with different population sizes may be insufficient.

Optical data communication for Earth observation satellite systems

NASA Astrophysics Data System (ADS)

Fischer, J.; Loecherbach, E.

1991-10-01

The current development status of optical communication engineering in comparison to the conventional microwave systems and the different configurations of the optical data communication for Earth observation satellite systems are described. An outlook to future optical communication satellite systems is given. During the last decade Earth observation became more and more important for the extension of the knowledge about our planet and the human influence on nature. Today pictures taken by satellites are used, for example, to discover mineral resources or to predict harvest, crops, climate, and environment variations and their influence on the population. A new and up to date application for Earth observation satellites can be the verification of disarmament arrangements and the control of crises areas. To solve these tasks a system of Earth observing satellites with sensors tailored to the envisaged mission is necessary. Besides these low Earth orbiting satellites, a global Earth observation system consists of at least two data relay satellites. The communication between the satellites will be established via Inter-Satellite Links (ISL) and Inter-Orbit Links (IOL). On these links, bitrates up to 1 Gbit/s must be taken into account. Due to the increasing scarcity of suitable frequencies, higher carrier frequencies must probably be considered, and possible interference with terrestrial radio relay systems are two main problems for a realization in microwave technique. One important step to tackle these problems is the use of optical frequencies for IOL's and ISL's.

Communication as care at end of life: an emerging issue from an exploratory action research study of renal end-of-life care for ethnic minorities in the UK.

PubMed

Wilkinson, Emma; Randhawa, Gurch; Brown, Edwina A; Da Silva Gane, Maria; Stoves, John; Warwick, Graham; Akhtar, Tahira; Magee, Regina; Sharman, Sue; Farrington, Ken

2014-09-01

South Asian people have a higher risk of developing kidney disease, are disproportionately represented in the patient population requiring renal replacement therapy and wait longer to receive a kidney transplant, compared with white Europeans. As a result, there is a demand for end-of-life care, which meets the needs of this group of patients. Providing end-of-life care to patients from different cultures is a challenge for renal services as there can be barriers to communication in the form of language, delegated decision-making within families and reluctance to discuss death. To explore end-of-life care for South Asians with kidney disease, 16 interviews with patients and 14 focus groups with care providers were conducted at four research sites in the UK with large South Asian populations. Using an action research design the data were analysed thematically and fed back to inform the research in a cyclical manner. If patients are not fully aware of their condition or of what end-of-life care is, it is less likely that they will be able to be involved in decision-making about their care and this is compounded where there are communication barriers. Variations in care provider awareness and experience of providing end-of-life care to South Asian patients, in turn, contributes to lack of patient awareness of end-of-life care. Communication as care at the end of life should be explored further. Researching the South Asian patient experience of end of life highlights many relevant and generalisable issues. © 2014 European Dialysis and Transplant Nurses Association/European Renal Care Association.

Integrating population dynamics into mapping human exposure to seismic hazard

NASA Astrophysics Data System (ADS)

Freire, S.; Aubrecht, C.

2012-11-01

Disaster risk is not fully characterized without taking into account vulnerability and population exposure. Assessment of earthquake risk in urban areas would benefit from considering the variation of population distribution at more detailed spatial and temporal scales, and from a more explicit integration of this improved demographic data with existing seismic hazard maps. In the present work, "intelligent" dasymetric mapping is used to model population dynamics at high spatial resolution in order to benefit the analysis of spatio-temporal exposure to earthquake hazard in a metropolitan area. These night- and daytime-specific population densities are then classified and combined with seismic intensity levels to derive new spatially-explicit four-class-composite maps of human exposure. The presented approach enables a more thorough assessment of population exposure to earthquake hazard. Results show that there are significantly more people potentially at risk in the daytime period, demonstrating the shifting nature of population exposure in the daily cycle and the need to move beyond conventional residence-based demographic data sources to improve risk analyses. The proposed fine-scale maps of human exposure to seismic intensity are mainly aimed at benefiting visualization and communication of earthquake risk, but can be valuable in all phases of the disaster management process where knowledge of population densities is relevant for decision-making.

Genetic variation facilitates seedling establishment but not population growth rate of a perennial invader.

PubMed

Li, Shou-Li; Vasemägi, Anti; Ramula, Satu

2016-01-01

Assessing the demographic consequences of genetic variation is fundamental to invasion biology. However, genetic and demographic approaches are rarely combined to explore the effects of genetic variation on invasive populations in natural environments. This study combined population genetics, demographic data and a greenhouse experiment to investigate the consequences of genetic variation for the population fitness of the perennial, invasive herb Lupinus polyphyllus. Genetic and demographic data were collected from 37 L. polyphyllus populations representing different latitudes in Finland, and genetic variation was characterized based on 13 microsatellite loci. Associations between genetic variation and population size, population density, latitude and habitat were investigated. Genetic variation was then explored in relation to four fitness components (establishment, survival, growth, fecundity) measured at the population level, and the long-term population growth rate (λ). For a subset of populations genetic variation was also examined in relation to the temporal variability of λ. A further assessment was made of the role of natural selection in the observed variation of certain fitness components among populations under greenhouse conditions. It was found that genetic variation correlated positively with population size, particularly at higher latitudes, and differed among habitat types. Average seedling establishment per population increased with genetic variation in the field, but not under greenhouse conditions. Quantitative genetic divergence (Q(ST)) based on seedling establishment in the greenhouse was smaller than allelic genetic divergence (F'(ST)), indicating that unifying selection has a prominent role in this fitness component. Genetic variation was not associated with average survival, growth or fecundity measured at the population level, λ or its variability. The study suggests that although genetic variation may facilitate plant invasions by increasing seedling establishment, it may not necessarily affect the long-term population growth rate. Therefore, established invasions may be able to grow equally well regardless of their genetic diversity. © 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.

How to tackle chemical communication? Relative proportions versus semiquantitative determination of compounds in lizard chemical secretions.

PubMed

García-Roa, Roberto; Sáiz, Jorge; Gómara, Belén; López, Pilar; Martín, José

2018-02-01

Knowledge about chemical communication in some vertebrates is still relatively limited. Squamates are a glaring example of this, even when recent evidences indicate that scents are involved in social and sexual interactions. In lizards, where our understanding of chemical communication has considerably progressed in the last few years, many questions about chemical interactions remain unanswered. A potential reason for this is the inherent complexity and technical limitations that some methodologies embody when analyzing the compounds used to convey information. We provide here a straightforward procedure to analyze lizard chemical secretions based on gas chromatography coupled to mass spectrometry that uses an internal standard for the semiquantification of compounds. We compare the results of this method with those obtained by the traditional procedure of calculating relative proportions of compounds. For such purpose, we designed two experiments to investigate if these procedures allowed revealing changes in chemical secretions 1) when lizards received previously a vitamin dietary supplementation or 2) when the chemical secretions were exposed to high temperatures. Our results show that the procedure based on relative proportions is useful to describe the overall chemical profile, or changes in it, at population or species levels. On the other hand, the use of the procedure based on semiquantitative determination can be applied when the target of study is the variation in one or more particular compounds of the sample, as it has proved more accurate detecting quantitative variations in the secretions. This method would reveal new aspects produced by, for example, the effects of different physiological and climatic factors that the traditional method does not show.

Survey on the availability, price and affordability of selected essential medicines for non-communicable diseases in community pharmacies of Kathmandu valley.

PubMed

Shrestha, Rajeev; Ghale, Anish; Chapagain, Bijay Raj; Gyawali, Mahasagar; Acharya, Trishna

2017-01-01

The access to essential medicines for non-communicable disease treatment is unacceptably low worldwide. The fundamental right to health cannot be fulfilled without equitable access to essential medicines. A cross-sectional study was carried out in 94 community pharmacies of Kathmandu valley. Non-probability quota sampling method was adopted for the purpose. Village Development Committees with more than 5000 populations were included in the study. The availability of the selected essential medicines, their price and producer identity were observed. Data entry and analysis were carried out in Microsoft Excel and Statistical package for social science. The availability of the essential medicines was not 100% in Kathmandu valley. High competition and high price variation were seen in metformin 500 mg (254.6%) and atorvastatin 10 mg (327.6%). The study showed that maximum (54.7%) brands were manufactured in Nepal. Furthermore, atorvastatin 10 mg (0.6 day wage) was found to be quite expensive, and glibenclamide 5 mg (0.1 day wage) was the cheapest one for diabetes mellitus treatment for 1 month of treatment period compared to daily wages of other essential medicines. The availability of the selected essential medicines was found to be ununiform and insufficient in the entire region. High competition was observed in the products with high price variation, and the access to cost-effective brand was poor. Furthermore, it was found that government salary is affordable to treat non-communicable disease with the help of the essential medicines.

The genetic architecture of sexually selected traits in two natural populations of Drosophila montana

PubMed Central

Veltsos, P; Gregson, E; Morrissey, B; Slate, J; Hoikkala, A; Butlin, R K; Ritchie, M G

2015-01-01

We investigated the genetic architecture of courtship song and cuticular hydrocarbon traits in two phygenetically distinct populations of Drosophila montana. To study natural variation in these two important traits, we analysed within-population crosses among individuals sampled from the wild. Hence, the genetic variation analysed should represent that available for natural and sexual selection to act upon. In contrast to previous between-population crosses in this species, no major quantitative trait loci (QTLs) were detected, perhaps because the between-population QTLs were due to fixed differences between the populations. Partitioning the trait variation to chromosomes suggested a broadly polygenic genetic architecture of within-population variation, although some chromosomes explained more variation in one population compared with the other. Studies of natural variation provide an important contrast to crosses between species or divergent lines, but our analysis highlights recent concerns that segregating variation within populations for important quantitative ecological traits may largely consist of small effect alleles, difficult to detect with studies of moderate power. PMID:26198076

Terrorism, civil war, one-sided violence and global burden of disease.

PubMed

Kerridge, Bradley T; Khan, Maria R; Sapkota, Amir

2012-01-01

Armed conflict and related violence, including terrorism and one-sided violence, has profound effects on people's health and lives. The purpose of this study was to determine the relationship between deaths due to terrorism, civil war and one-sided violence from 1994-2000 and disability-adjusted life years (DALYs) occurring in 2002 attributable to all causes and specific communicable and noncommunicable diseases. Deaths resulting from terrorism, war and one-sided violence were positively associated with all cause as well as a number of communicable and noncommunicable disease-specific DALYs across the majority of sex and age subgroups of the populace, controlling for an array of economic factors empirically shown to affect public health. Overall, a 1.0% increase in deaths due to terrorism, civil war and one-sided violence from 1994-2000 was associated with a 0.16% increase in DALYs lost to all causes in 2002 in the total world population. There was little variation in the magnitude of these associations between males and females and between communicable and noncommunicable diseases. The results of the present study can begin to guide post-conflict recovery by focusing on interventions targeting both noncommunicable as well as communicable diseases, thereby highlighting the full health costs of war and ultimately providing a strong rationale for promoting peace.

Variation in MHC genotypes in two populations of house sparrow (Passer domesticus) with different population histories.

PubMed

Borg, Asa Alexandra; Pedersen, Sindre Andre; Jensen, Henrik; Westerdahl, Helena

2011-10-01

Small populations are likely to have a low genetic ability for disease resistance due to loss of genetic variation through inbreeding and genetic drift. In vertebrates, the highest genetic diversity of the immune system is located at genes within the major histocompatibility complex (MHC). Interestingly, parasite-mediated selection is thought to potentially maintain variation at MHC loci even in populations that are monomorphic at other loci. Therefore, general loss of genetic variation in the genome may not necessarily be associated with low variation at MHC loci. We evaluated inter- and intrapopulation variation in MHC genotypes between an inbred (Aldra) and a relatively outbred population (Hestmannøy) of house sparrows (Passer domesticus) in a metapopulation at Helgeland, Norway. Genomic (gDNA) and transcribed (cDNA) alleles of functional MHC class I and IIB loci, along with neutral noncoding microsatellite markers, were analyzed to obtain relevant estimates of genetic variation. We found lower allelic richness in microsatellites in the inbred population, but high genetic variation in MHC class I and IIB loci in both populations. This suggests that also the inbred population could be under balancing selection to maintain genetic variation for pathogen resistance.

Variation in MHC genotypes in two populations of house sparrow (Passer domesticus) with different population histories

PubMed Central

Borg, Åsa Alexandra; Pedersen, Sindre Andre; Jensen, Henrik; Westerdahl, Helena

2011-01-01

Small populations are likely to have a low genetic ability for disease resistance due to loss of genetic variation through inbreeding and genetic drift. In vertebrates, the highest genetic diversity of the immune system is located at genes within the major histocompatibility complex (MHC). Interestingly, parasite-mediated selection is thought to potentially maintain variation at MHC loci even in populations that are monomorphic at other loci. Therefore, general loss of genetic variation in the genome may not necessarily be associated with low variation at MHC loci. We evaluated inter- and intrapopulation variation in MHC genotypes between an inbred (Aldra) and a relatively outbred population (Hestmannøy) of house sparrows (Passer domesticus) in a metapopulation at Helgeland, Norway. Genomic (gDNA) and transcribed (cDNA) alleles of functional MHC class I and IIB loci, along with neutral noncoding microsatellite markers, were analyzed to obtain relevant estimates of genetic variation. We found lower allelic richness in microsatellites in the inbred population, but high genetic variation in MHC class I and IIB loci in both populations. This suggests that also the inbred population could be under balancing selection to maintain genetic variation for pathogen resistance. PMID:22393491

Ecological drivers of group living in two populations of the communally rearing rodent, Octodon degus

PubMed Central

Sobrero, Raúl; Quirici, Verónica; Castro, Rodrigo A.; Tolhuysen, Liliana Ortiz; Vargas, Francisco; Burger, Joseph Robert; Quispe, René; Villavicencio, Camila P.; Vásquez, Rodrigo A.; Hayes, Loren D.

2012-01-01

Intraspecific variation in sociality is thought to reflect a trade-off between current fitness benefits and costs that emerge from individuals' decision to join or leave groups. Since those benefits and costs may be influenced by ecological conditions, ecological variation remains a major, ultimate cause of intraspecific variation in sociality. Intraspecific comparisons of mammalian sociality across populations facing different environmental conditions have not provided a consistent relationship between ecological variation and group-living. Thus, we studied two populations of the communally rearing rodent Octodon degus to determine how co-variation between sociality and ecology supports alternative ecological causes of group living. In particular, we examined how variables linked to predation risk, thermal conditions, burrowing costs, and food availability predicted temporal and population variation in sociality. Our study revealed population and temporal variation in total group size and group composition that covaried with population and yearly differences in ecology. In particular, predation risk and burrowing costs are supported as drivers of this social variation in degus. Thermal differences, food quantity and quality were not significant predictors of social group size. In contrast to between populations, social variation within populations was largely uncoupled from ecological differences. PMID:22344477

Individuals in food webs: the relationships between trophic position, omnivory and among-individual diet variation.

PubMed

Svanbäck, Richard; Quevedo, Mario; Olsson, Jens; Eklöv, Peter

2015-05-01

Among-individual diet variation is common in natural populations and may occur at any trophic level within a food web. Yet, little is known about its variation among trophic levels and how such variation could affect phenotypic divergence within populations. In this study we investigate the relationships between trophic position (the population's range and average) and among-individual diet variation. We test for diet variation among individuals and across size classes of Eurasian perch (Perca fluviatilis), a widespread predatory freshwater fish that undergoes ontogenetic niche shifts. Second, we investigate among-individual diet variation within fish and invertebrate populations in two different lake communities using stable isotopes. Third, we test potential evolutionary implications of population trophic position by assessing the relationship between the proportion of piscivorous perch (populations of higher trophic position) and the degree of phenotypic divergence between littoral and pelagic perch sub-populations. We show that among-individual diet variation is highest at intermediate trophic positions, and that this high degree of among-individual variation likely causes an increase in the range of trophic positions among individuals. We also found that phenotypic divergence was negatively related to trophic position in a population. This study thus shows that trophic position is related to and may be important for among-individual diet variation as well as to phenotypic divergence within populations.

Sexual Dimorphism in Melanin Pigmentation, Feather Coloration and Its Heritability in the Barn Swallow (Hirundo rustica)

PubMed Central

Saino, Nicola; Romano, Maria; Rubolini, Diego; Teplitsky, Celine; Ambrosini, Roberto; Caprioli, Manuela; Canova, Luca; Wakamatsu, Kazumasa

2013-01-01

Melanin is the main pigment in animal coloration and considerable variation in the concentrations of the two melanin forms (pheo- and eumlanin) in pigmented tissues exists among populations and individuals. Melanin-based coloration is receiving increasing attention particularly in socio-sexual communication contexts because the melanocortin system has been hypothesized to provide a mechanistic basis for covariation between coloration and fitness traits. However, with few notable exceptions, little detailed information is available on inter-individual and inter-population variation in melanin pigmentation and on its environmental, genetic and ontogenetic components. Here, we investigate melanin-based coloration in an Italian population of a passerine bird, the barn swallow (Hirundo rustica rustica), its sex- and age-related variation, and heritability. The concentrations of eu- and pheomelanin in the throat (brown) and belly (white-to-brownish) feathers differed between sexes but not according to age. The relative concentration of either melanin (Pheo:Eu) differed between sexes in throat but not in belly feathers, and the concentrations in males compared to females were larger in belly than in throat feathers. There were weak correlations between the concentrations of melanins within as well as among plumage regions. Coloration of belly feathers was predicted by the concentration of both melanins whereas coloration of throat feathers was only predicted by pheomelanin in females. In addition, Pheo:Eu predicted coloration of throat feathers in females and that of belly feathers in males. Finally, we found high heritability of color of throat feathers. Melanization was found to differ from that recorded in Hirundo rustica rustica from Scotland or from H. r. erythrogaster from North America. Hence, present results show that pigmentation strategies vary in a complex manner according to sex and plumage region, and also among geographical populations, potentially reflecting adaptation to different natural and sexual selection regimes, and that some coloration components seem to be highly heritable. PMID:23469134

The Grandest Genetic Experiment Ever Performed on Man? - A Y-Chromosomal Perspective on Genetic Variation in India.

PubMed

Carvalho-Silva, Denise R; Tyler-Smith, Chris

2008-05-01

We have analysed Y-chromosomal data from Indian caste, Indian tribal and East Asian populations in order to investigate the impact of the caste system on male genetic variation. We find that variation within populations is lower in India than in East Asia, while variation between populations is overall higher. This observation can be explained by greater subdivision within the Indian population, leading to more genetic drift. However, the effect is most marked in the tribal populations, and the level of variation between caste populations is similar to the level between Chinese populations. The caste system has therefore had a detectable impact on Y-chromosomal variation, but this has been less strong than the influence of the tribal system, perhaps because of larger population sizes in the castes, more gene flow or a shorter period of time.

Living in isolation - population structure, reproduction, and genetic variation of the endangered plant species Dianthus gratianopolitanus (Cheddar pink).

PubMed

Putz, Christina M; Schmid, Christoph; Reisch, Christoph

2015-09-01

The endangered plant species Dianthus gratianopolitanus exhibits a highly fragmented distribution range comprising many isolated populations. Based upon this pattern of distribution, we selected a study region in Switzerland with a lower magnitude of isolation (Swiss Jura) and another study region in Germany with a higher degree of isolation (Franconian Jura). In each region, we chose ten populations to analyze population structure, reproduction, and genetic variation in a comparative approach. Therefore, we determined population density, cushion size, and cushion density to analyze population structure, investigated reproductive traits, including number of flowers, capsules, and germination rate, and analyzed amplified fragment length polymorphisms to study genetic variation. Population and cushion density were credibly higher in German than in Swiss populations, whereas reproductive traits and genetic variation within populations were similar in both study regions. However, genetic variation among populations and isolation by distance were stronger in Germany than in Switzerland. Generally, cushion size and density as well as flower and capsule production increased with population size and density, whereas genetic variation decreased with population density. In contrast to our assumptions, we observed denser populations and cushions in the region with the higher magnitude of isolation, whereas reproductive traits and genetic variation within populations were comparable in both regions. This corroborates the assumption that stronger isolation must not necessarily result in the loss of fitness and genetic variation. Furthermore, it supports our conclusion that the protection of strongly isolated populations contributes essentially to the conservation of a species' full evolutionary potential.

Paths and patterns: the biology and physics of swimming bacterial populations

NASA Technical Reports Server (NTRS)

Kessler, J. O.; Strittmatter, R. P.; Swartz, D. L.; Wiseley, D. A.; Wojciechowski, M. F.

1995-01-01

The velocity distribution of swimming micro-organisms depends on directional cues supplied by the environment. Directional swimming within a bounded space results in the accumulation of organisms near one or more surfaces. Gravity, gradients of chemical concentration and illumination affect the motile behaviour of individual swimmers. Concentrated populations of organisms scatter and absorb light or consume molecules, such as oxygen. When supply is one-sided, consumption creates gradients; the presence of the population alters the intensity and the symmetry of the environmental cues. Patterns of cues interact dynamically with patterns of the consumer population. In suspensions, spatial variations in the concentration of organisms are equivalent to variations of mean mass density of the fluid. When organisms accumulate in one region whilst moving away from another region, the force of gravity causes convection that translocates both organisms and dissolved substances. The geometry of the resulting concentration-convection patterns has features that are remarkably reproducible. Of interest for biology are (1) the long-range organisation achieved by organisms that do not communicate, and (2) that the entire system, consisting of fluid, cells, directional supply of consumables, boundaries and gravity, generates a dynamic that improves the organisms' habitat by enhancing transport and mixing. Velocity distributions of the bacterium Bacillus subtilis have been measured within the milieu of the spatially and temporally varying oxygen concentration which they themselves create. These distributions of swimming speed and direction are the fundamental ingredients required for a quantitative mathematical treatment of the patterns. The quantitative measurement of swimming behaviour also contributes to our understanding of aerotaxis of individual cells.

Public Relations and Interpersonal Communication.

ERIC Educational Resources Information Center

Lance, Elizabeth P.

Despite a lack of consensus on theoretical perspectives on public relations and variations in the ways it and interpersonal communication are defined, public relations may be related to interpersonal communication in three ways: (1) it is two-way communication, (2) it is personal, and (3) it is relational. Even in activities having the highest…

Culture and Palliative Care: Preferences, Communication, Meaning, and Mutual Decision Making.

PubMed

Cain, Cindy L; Surbone, Antonella; Elk, Ronit; Kagawa-Singer, Marjorie

2018-05-01

Palliative care is gaining acceptance across the world. However, even when palliative care resources exist, both the delivery and distribution of services too often are neither equitably nor acceptably provided to diverse population groups. The goal of this study was to illustrate tensions in the delivery of palliative care for diverse patient populations to help clinicians to improve care for all. We begin by defining and differentiating culture, race, and ethnicity, so that these terms-often used interchangeably-are not conflated and are more effectively used in caring for diverse populations. We then present examples from an integrative literature review of recent research on culture and palliative care to illustrate both how and why varied responses to pain and suffering occur in different patterns, focusing on four areas of palliative care: the formation of care preferences, communication patterns, different meanings of suffering, and decision-making processes about care. For each area, we provide international and multiethnic examples of variations that emphasize the need for personalization of care and the avoidance of stereotyping beliefs and practices without considering individual circumstances and life histories. We conclude with recommendations for improving palliative care research and practice with cultural perspectives, emphasizing the need to work in partnerships with patients, their family members, and communities to identify and negotiate culturally meaningful care, promote quality of life, and ensure the highest quality palliative care for all, both domestically and internationally. Copyright © 2018 American Academy of Hospice and Palliative Medicine. Published by Elsevier Inc. All rights reserved.

Promoting Community Health Resources: Preferred Communication Strategies

USDA-ARS?s Scientific Manuscript database

Background: Community health promotion efforts involve communicating resource information to priority populations. Which communication strategies are most effective is largely unknown for specific populations. Objective: A random-dialed telephone survey was conducted to assess health resource comm...

[Communication behavior between parents and their adolescent children and correlation with indicators of self concept].

PubMed

Kreppner, K

1996-01-01

Formats of communication within families are believed to be relevant contexts for children's development. Cultural values, norms, and interpretation patterns are transferred from parents to children within the family's specific communication framework. By the same token, skills to maintain the balance of living together or to realize one's own wishes are acquired within the scope of extant formats of exchange among family members. Puberty is a period, where a child strives for more autonomy and tends to dispute present parent-child relationships. The focus of the study is on links between formats of communication within the family and adolescents' estimations of the relationships with their parents and also adolescents' judgments about their self-esteem. 67 families with an adolescent child (between 11 and 12 years old at the beginning of data collection) participated in a longitudinal study, in which adolescents judged the quality of their relationship with parents as well as their self-esteem every six months over a period of three and a half years (8 waves). In addition, concrete communication behavior between parents and adolescents was observed and recorded during the first, fourth, sixth, and eight wave of data collection. Results point to considerable differences among adolescents' judgments concerning their quality of relationship with the parents and their self-esteem. Groups could be formed according to these differences. Data also show that adolescents show a high degree of constancy in their estimations over time. However, communication behaviors in parent-adolescent dyads showed divergent patterns of communication across the different groups on the one hand, and different degrees of variation of communication formats within groups over time on the other, dependent on whether adolescents belonged to the group of high quality relationship and self-esteem (considerable variation over time) or to the group of low quality relationship and self-esteem (less variation over time). Results are discussed under the perspective of adolescents' different experiences in family communication, and implications of possible links between development of self-esteem and adaptive or nonadaptive variations in family communication are considered.

Transcriptome analysis of the sea cucumber (Apostichopus japonicus) with variation in individual growth.

PubMed

Gao, Lei; He, Chongbo; Bao, Xiangbo; Tian, Meilin; Ma, Zhen

2017-01-01

The sea cucumber (Apostichopus japonicus) is an economically important aquaculture species in China. However, the serious individual growth variation often caused financial losses to farmers and the genetic mechanisms are poorly understood. In the present study, the extensively analysis at the transcriptome level for individual growth variation in sea cucumber was carried out. A total of 118946 unigenes were assembled from 255861 transcripts, with N50 of 1700. Of all unigenes, about 23% were identified with at least one significant match to known databases. In all four pair of comparison, 1840 genes were found to be expressed differently. Global hypometabolism was found to be occurred in the slow growing population, based on which the hypothesis was raised that growth retardation in individual growth variation of sea cucumber is one type of dormancy which is used to be against to adverse circumstances. Besides, the pathways such as ECM-receptor interaction and focal adhesion were enriched in the maintenance of cell and tissue structure and communication. Further, 76645 SSRs, 765242 SNPs and 146886 ins-dels were detected in the current study providing an extensive set of data for future studies of genetic mapping and selective breeding. In summary, these results will provides deep insight into the molecular basis of individual growth variation in marine invertebrates, and be valuable for understanding the physiological differences of growth process.

Rhythm as a Coordinating Device: Entrainment With Disordered Speech

PubMed Central

Borrie, Stephanie A.; Liss, Julie M.

2014-01-01

Purpose The rhythmic entrainment (coordination) of behavior during human interaction is a powerful phenomenon, considered essential for successful communication, supporting social and emotional connection, and facilitating sense-making and information exchange. Disruption in entrainment likely occurs in conversations involving those with speech and language impairment, but its contribution to communication disorders has not been defined. As a first step to exploring this phenomenon in clinical populations, the present investigation examined the influence of disordered speech on the speech production properties of healthy interactants. Method Twenty-nine neurologically healthy interactants participated in a quasi-conversational paradigm, in which they read sentences (response) in response to hearing prerecorded sentences (exposure) from speakers with dysarthria (n = 4) and healthy controls (n = 4). Recordings of read sentences prior to the task were also collected (habitual). Results Findings revealed that interactants modified their speaking rate and pitch variation to align more closely with the disordered speech. Production shifts in these rhythmic properties, however, remained significantly different from corresponding properties in dysarthric speech. Conclusion Entrainment offers a new avenue for exploring speech and language impairment, addressing a communication process not currently explained by existing frameworks. This article offers direction for advancing this line of inquiry. PMID:24686410

From data to decisions? Exploring how healthcare payers respond to the NHS Atlas of Variation in Healthcare in England.

PubMed

Schang, Laura; Morton, Alec; DaSilva, Philip; Bevan, Gwyn

2014-01-01

Although information on variations in health service performance is now more widely available, relatively little is known about how healthcare payers use this information to improve resource allocation. We explore to what extent and how Primary Care Trusts (PCTs) in England have used the NHS Atlas of Variation in Healthcare, which has highlighted small area variation in rates of expenditure, activity and outcome. Data collection involved an email survey among PCT Chief Executives and a telephone follow-up to reach non-respondents (total response: 53 of 151 of PCTs, 35%). 45 senior to mid-level staff were interviewed to probe themes emerging from the survey. The data were analysed using a matrix-based Framework approach. Just under half of the respondents (25 of 53 PCTs) reported not using the Atlas, either because they had not been aware of it, lacked staff capacity to analyse it, or did not perceive it as applicable to local decision-making. Among the 28 users, the Atlas served as a prompt to understand variations and as a visual tool to facilitate communication with clinicians. Achieving clarity on which variations are unwarranted and agreeing on responsibilities for action appeared to be important factors in moving beyond initial information gathering towards decisions about resource allocation and behaviour change. Many payers were unable to use information on small area variations in expenditure, activity and outcome. To change this what is additionally required are appropriate tools to understand causes of unexplained variation, in particular unwarranted variation, and enable remedial actions to be prioritised in terms of their contribution to population health. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

Autism, language and communication in children with sex chromosome trisomies.

PubMed

Bishop, Dorothy V M; Jacobs, Patricia A; Lachlan, Katherine; Wellesley, Diana; Barnicoat, Angela; Boyd, Patricia A; Fryer, Alan; Middlemiss, Prisca; Smithson, Sarah; Metcalfe, Kay; Shears, Deborah; Leggett, Victoria; Nation, Kate; Scerif, Gaia

2011-10-01

Sex chromosome trisomies (SCTs) are found on amniocentesis in 2.3-3.7 per 1000 same-sex births, yet there is a limited database on which to base a prognosis. Autism has been described in postnatally diagnosed cases of Klinefelter syndrome (XXY karyotype), but the prevalence in non-referred samples, and in other trisomies, is unclear. The authors recruited the largest sample including all three SCTs to be reported to date, including children identified on prenatal screening, to clarify this issue. Parents of children with a SCT were recruited either via prenatal screening or via a parental support group, to give a sample of 58 XXX, 19 XXY and 58 XYY cases. Parents were interviewed using the Vineland Adaptive Behavior Scales and completed questionnaires about the communicative development of children with SCTs and their siblings (42 brothers and 26 sisters). Rates of language and communication problems were high in all three trisomies. Diagnoses of autism spectrum disorder (ASD) were found in 2/19 cases of XXY (11%) and 11/58 XYY (19%). After excluding those with an ASD diagnosis, communicative profiles indicative of mild autistic features were common, although there was wide individual variation. Autistic features have not previously been remarked upon in studies of non-referred samples with SCTs, yet the rate is substantially above population levels in this sample, even when attention is restricted to early-identified cases. The authors hypothesise that X-linked and Y-linked neuroligins may play a significant role in the aetiology of communication impairments and ASD.

THERACOM: a systematic review of the evidence base for interventions to improve Therapeutic Communications between black and minority ethnic populations and staff in specialist mental health services.

PubMed

Bhui, Kamaldeep; McCabe, Rosemarie; Weich, Scott; Singh, Swaran; Johnson, Mark; Szczepura, Ala

2013-02-25

Black and Minority Ethnic (BME) groups in receipt of specialist mental health care have reported higher rates of detention under the mental health act, less use of psychological therapies, and more dissatisfaction. Although many explanations have been put forward to explain this, a failure of therapeutic communications may explain poorer satisfaction, disengagement from services and ethnic variations in access to less coercive care. Interventions that improve therapeutic communications may offer new approaches to tackle ethnic inequalities in experiences and outcomes. The THERACOM project is an HTA-funded evidence synthesis review of interventions to improve therapeutic communications between black and minority ethnic patients in contact with specialist mental health services and staff providing those services. This article sets out the protocol methods for a necessarily broad review topic, including appropriate search strategies, dilemmas for classifying different types of therapeutic communications and expectations of the types of interventions to improve them. The review methods will accommodate unexpected types of study and interventions. The findings will be reported in 2013, including a synthesis of the quantitative and grey literature. A particular methodological challenge is to identify and rate the quality of many different study types, for example, randomised controlled trials, observational quantitative studies, qualitative studies and case studies, which comprise the full range of hierarchies of evidence. We discuss the preliminary methodological challenges and some solutions. (PROSPERO registration number: CRD42011001661).

THERACOM: a systematic review of the evidence base for interventions to improve Therapeutic Communications between black and minority ethnic populations and staff in specialist mental health services

PubMed Central

2013-01-01

Background Black and Minority Ethnic (BME) groups in receipt of specialist mental health care have reported higher rates of detention under the mental health act, less use of psychological therapies, and more dissatisfaction. Although many explanations have been put forward to explain this, a failure of therapeutic communications may explain poorer satisfaction, disengagement from services and ethnic variations in access to less coercive care. Interventions that improve therapeutic communications may offer new approaches to tackle ethnic inequalities in experiences and outcomes. Methods The THERACOM project is an HTA-funded evidence synthesis review of interventions to improve therapeutic communications between black and minority ethnic patients in contact with specialist mental health services and staff providing those services. This article sets out the protocol methods for a necessarily broad review topic, including appropriate search strategies, dilemmas for classifying different types of therapeutic communications and expectations of the types of interventions to improve them. The review methods will accommodate unexpected types of study and interventions. The findings will be reported in 2013, including a synthesis of the quantitative and grey literature. Discussion A particular methodological challenge is to identify and rate the quality of many different study types, for example, randomised controlled trials, observational quantitative studies, qualitative studies and case studies, which comprise the full range of hierarchies of evidence. We discuss the preliminary methodological challenges and some solutions. (PROSPERO registration number: CRD42011001661). PMID:23442299

Using principal components analysis to explore competence and confidence in student nurses as users of information and communication technologies.

PubMed

Todhunter, Fern

2015-07-01

To report on the relationship between competence and confidence in nursing students as users of information and communication technologies, using principal components analysis. In nurse education, learning about and learning using information and communication technologies is well established. Nursing students are one of the undergraduate populations in higher education required to use these resources for academic work and practice learning. Previous studies showing mixed experiences influenced the choice of an exploratory study to find out about information and communication technologies competence and confidence. A 48-item survey questionnaire was administered to a volunteer sample of first- and second-year nursing students between July 2008-April 2009. The cohort ( N  =   375) represented 18·75% of first- and second-year undergraduates. A comparison between this work and subsequent studies reveal some similar ongoing issues and ways to address them. A principal components analysis (PCA) was carried out to determine the strength of the correlation between information and communication technologies competence and confidence. The aim was to show the presence of any underlying dimensions in the transformed data that would explain any variations in information and communication technologies competence and confidence. Cronbach's alpha values showed fair to good internal consistency. The five component structure gave medium to high results and explained 44·7% of the variance in the original data. Confidence had a high representation. The findings emphasized the shift towards social learning approaches for information and communication technologies. Informal social collaboration found favour with nursing students. Learning through talking, watching and listening all play a crucial role in the development of computing skills.

Mitochondrial Variation among the Aymara and the Signatures of Population Expansion in the Central Andes

PubMed Central

BATAI, KEN; WILLIAMS, SLOAN R.

2015-01-01

Objectives The exploitation of marine resources and intensive agriculture led to a marked population increase early in central Andean prehistory. Constant historic and prehistoric population movements also characterize this region. These features undoubtedly affected regional genetic variation, but the exact nature of these effects remains uncertain. Methods Mitochondrial DNA (mtDNA) hypervariable region I sequence variation in 61 Aymara individuals from La Paz, Bolivia, was analyzed and compared to sequences from 47 other South American populations to test hypotheses of whether increased female effective population size and gene flow influenced the mtDNA variation among central Andean populations. Results The Aymara and Quechua were genetically diverse showing evidence of population expansion and large effective population size, and a demographic expansion model fits the mtDNA variation found among central Andean populations well. Estimated migration rates and the results of AMOVA and multidimensional scaling analysis suggest that female gene flow was also an important factor, influencing genetic variation among the central Andeans as well as lowland populations from western South America. mtDNA variation in south central Andes correlated better with geographic proximity than with language, and fit a population continuity model. Conclusion The mtDNA data suggests that the central Andeans experienced population expansion, most likely because of rapid demographic expansion after introduction of intensive agriculture, but roles of female gene flow need to be further explored. PMID:24449040

Migration and the epidemiological transition: insights from the Agincourt sub-district of northeast South Africa

PubMed Central

Collinson, Mark A.; White, Michael J.; Bocquier, Philippe; McGarvey, Stephen T.; Afolabi, Sulaimon A.; Clark, Samuel J.; Kahn, Kathleen; Tollman, Stephen M.

2014-01-01

Background Migration and urbanization are central to sustainable development and health, but data on temporal trends in defined populations are scarce. Healthy men and women migrate because opportunities for employment and betterment are not equally distributed geographically. The disruption can result in unhealthy exposures and environments and income returns for the origin household. Objectives The objectives of the paper are to describe the patterns, levels, and trends of temporary migration in rural northeast South Africa; the mortality trends by cause category over the period 2000–2011; and the associations between temporary migration and mortality by broad cause of death categories. Method Longitudinal, Agincourt Health and Demographic Surveillance System data are used in a continuous, survival time, competing-risk model. Findings In rural, northeast South Africa, temporary migration, which involves migrants relocating mainly for work purposes and remaining linked to the rural household, is more important than age and sex in explaining variations in mortality, whatever the cause. In this setting, the changing relationship between temporary migration and communicable disease mortality is primarily affected by reduced exposure of the migrant to unhealthy conditions. The study suggests that the changing relationship between temporary migration and non-communicable disease mortality is mainly affected by increased livelihood benefits of longer duration migration. Conclusion Since temporary migration is not associated with communicable diseases only, public health policies should account for population mobility whatever the targeted health risk. There is a need to strengthen the rural health care system, because migrants tend to return to the rural households when they need health care. PMID:24848656

Migration and the epidemiological transition: insights from the Agincourt sub-district of northeast South Africa.

PubMed

Collinson, Mark A; White, Michael J; Bocquier, Philippe; McGarvey, Stephen T; Afolabi, Sulaimon A; Clark, Samuel J; Kahn, Kathleen; Tollman, Stephen M

2014-01-01

Migration and urbanization are central to sustainable development and health, but data on temporal trends in defined populations are scarce. Healthy men and women migrate because opportunities for employment and betterment are not equally distributed geographically. The disruption can result in unhealthy exposures and environments and income returns for the origin household. The objectives of the paper are to describe the patterns, levels, and trends of temporary migration in rural northeast South Africa; the mortality trends by cause category over the period 2000-2011; and the associations between temporary migration and mortality by broad cause of death categories. Longitudinal, Agincourt Health and Demographic Surveillance System data are used in a continuous, survival time, competing-risk model. In rural, northeast South Africa, temporary migration, which involves migrants relocating mainly for work purposes and remaining linked to the rural household, is more important than age and sex in explaining variations in mortality, whatever the cause. In this setting, the changing relationship between temporary migration and communicable disease mortality is primarily affected by reduced exposure of the migrant to unhealthy conditions. The study suggests that the changing relationship between temporary migration and non-communicable disease mortality is mainly affected by increased livelihood benefits of longer duration migration. Since temporary migration is not associated with communicable diseases only, public health policies should account for population mobility whatever the targeted health risk. There is a need to strengthen the rural health care system, because migrants tend to return to the rural households when they need health care.

Use of a Video Scoring Anchor for Rapid Serial Assessment of Social Communication in Toddlers.

PubMed

Marrus, Natasha; Kennon-McGill, Stefanie; Harris, Brooke; Zhang, Yi; Glowinski, Anne L; Constantino, John N

2018-03-14

Reciprocal social behavior (RSB), an early-emerging capacity to engage in social contingency-which is foundational for both social learning and social competency-is hypothesized to be disrupted in autism spectrum disorder (ASD). The ability to quantify the full range of RSB during the toddler period, when core symptoms of ASD often arise, is pivotal for evaluating early risk for ASD, characterizing social development, and tracking response to early interventions. However, important parameters of variation in RSB-especially prior to the development of verbal language-can be nuanced and difficult to characterize using questionnaire-based methods. To address this challenge, we developed a system for measuring quantitative variation in RSB in toddlers (ages 18 - 30 months) that incorporated not only standard questionnaire data from caregivers but also a novel set of video-referenced items, through which a respondent compares the behavior of a subject to that observed in a short video of a young child manifesting a highly competent level of social communication. Testing of this measure in a general population sample of twins confirmed that both the video-referenced items and the RSB Total Score (video-referenced items plus non-video-referenced items) displayed unimodal, continuous distributions, strong internal consistency, marked preservation of individual differences, and extremely high heritability. In addition, video-referenced items were particularly sensitive to quantifying incremental changes in social communication, a major element of RSB, over the course of early childhood development. Scores on the vrRSB clearly differentiated children with and without ASD and these data comprise an initial validation of this promising method for quantifying early RSB-cross-sectionally, over time, and as a function of early intervention.

Theoretical Approaches to Political Communication.

ERIC Educational Resources Information Center

Chesebro, James W.

Political communication appears to be emerging as a theoretical and methodological academic area of research within both speech-communication and political science. Five complimentary approaches to political science (Machiavellian, iconic, ritualistic, confirmational, and dramatistic) may be viewed as a series of variations which emphasize the…

Variation in seed dormancy quantitative trait loci in Arabidopsis thaliana originating from one site.

PubMed

Silady, Rebecca A; Effgen, Sigi; Koornneef, Maarten; Reymond, Matthieu

2011-01-01

A Quantitative Trait Locus (QTL) analysis was performed using two novel Recombinant Inbred Line (RIL) populations, derived from the progeny between two Arabidopsis thaliana genotypes collected at the same site in Kyoto (Japan) crossed with the reference laboratory strain Landsberg erecta (Ler). We used these two RIL populations to determine the genetic basis of seed dormancy and flowering time, which are assumed to be the main traits controlling life history variation in Arabidopsis. The analysis revealed quantitative variation for seed dormancy that is associated with allelic variation at the seed dormancy QTL DOG1 (for Delay Of Germination 1) in one population and at DOG6 in both. These DOG QTL have been previously identified using mapping populations derived from accessions collected at different sites around the world. Genetic variation within a population may enhance its ability to respond accurately to variation within and between seasons. In contrast, variation for flowering time, which also segregated within each mapping population, is mainly governed by the same QTL.

Divergent selection along climatic gradients in a rare central European endemic species, Saxifraga sponhemica

PubMed Central

Walisch, Tania J.; Colling, Guy; Bodenseh, Melanie; Matthies, Diethart

2015-01-01

Background and Aims The effects of habitat fragmentation on quantitative genetic variation in plant populations are still poorly known. Saxifraga sponhemica is a rare endemic of Central Europe with a disjunct distribution, and a stable and specialized habitat of treeless screes and cliffs. This study therefore used S. sponhemica as a model species to compare quantitative and molecular variation in order to explore (1) the relative importance of drift and selection in shaping the distribution of quantitative genetic variation along climatic gradients; (2) the relationship between plant fitness, quantitative genetic variation, molecular genetic variation and population size; and (3) the relationship between the differentiation of a trait among populations and its evolvability. Methods Genetic variation within and among 22 populations from the whole distribution area of S. sponhemica was studied using RAPD (random amplified polymorphic DNA) markers, and climatic variables were obtained for each site. Seeds were collected from each population and germinated, and seedlings were transplanted into a common garden for determination of variation in plant traits. Key Results In contrast to previous results from rare plant species, strong evidence was found for divergent selection. Most population trait means of S. sponhemica were significantly related to climate gradients, indicating adaptation. Quantitative genetic differentiation increased with geographical distance, even when neutral molecular divergence was controlled for, and QST exceeded FST for some traits. The evolvability of traits was negatively correlated with the degree of differentiation among populations (QST), i.e. traits under strong selection showed little genetic variation within populations. The evolutionary potential of a population was not related to its size, the performance of the population or its neutral genetic diversity. However, performance in the common garden was lower for plants from populations with reduced molecular genetic variation, suggesting inbreeding depression due to genetic erosion. Conclusions The findings suggest that studies of molecular and quantitative genetic variation may provide complementary insights important for the conservation of rare species. The strong differentiation of quantitative traits among populations shows that selection can be an important force for structuring variation in evolutionarily important traits even for rare endemic species restricted to very specific habitats. PMID:25862244

Quality of Doctor-Patient Communication through the Eyes of the Patient: Variation According to the Patient's Educational Level

ERIC Educational Resources Information Center

Aelbrecht, Karolien; Rimondini, Michela; Bensing, Jozien; Moretti, Francesca; Willems, Sara; Mazzi, Mariangela; Fletcher, Ian; Deveugele, Myriam

2015-01-01

Good doctor-patient communication may lead to better compliance, higher patient satisfaction, and finally, better health. Although the social variance in how physicians and patients communicate is clearly demonstrated, little is known about what patients with different educational attainments actually prefer in doctor-patient communication. In…

The Impact of Accelerating Faster than Exponential Population Growth on Genetic Variation

PubMed Central

Reppell, Mark; Boehnke, Michael; Zöllner, Sebastian

2014-01-01

Current human sequencing projects observe an abundance of extremely rare genetic variation, suggesting recent acceleration of population growth. To better understand the impact of such accelerating growth on the quantity and nature of genetic variation, we present a new class of models capable of incorporating faster than exponential growth in a coalescent framework. Our work shows that such accelerated growth affects only the population size in the recent past and thus large samples are required to detect the models’ effects on patterns of variation. When we compare models with fixed initial growth rate, models with accelerating growth achieve very large current population sizes and large samples from these populations contain more variation than samples from populations with constant growth. This increase is driven almost entirely by an increase in singleton variation. Moreover, linkage disequilibrium decays faster in populations with accelerating growth. When we instead condition on current population size, models with accelerating growth result in less overall variation and slower linkage disequilibrium decay compared to models with exponential growth. We also find that pairwise linkage disequilibrium of very rare variants contains information about growth rates in the recent past. Finally, we demonstrate that models of accelerating growth may substantially change estimates of present-day effective population sizes and growth times. PMID:24381333

The impact of accelerating faster than exponential population growth on genetic variation.

PubMed

Reppell, Mark; Boehnke, Michael; Zöllner, Sebastian

2014-03-01

Current human sequencing projects observe an abundance of extremely rare genetic variation, suggesting recent acceleration of population growth. To better understand the impact of such accelerating growth on the quantity and nature of genetic variation, we present a new class of models capable of incorporating faster than exponential growth in a coalescent framework. Our work shows that such accelerated growth affects only the population size in the recent past and thus large samples are required to detect the models' effects on patterns of variation. When we compare models with fixed initial growth rate, models with accelerating growth achieve very large current population sizes and large samples from these populations contain more variation than samples from populations with constant growth. This increase is driven almost entirely by an increase in singleton variation. Moreover, linkage disequilibrium decays faster in populations with accelerating growth. When we instead condition on current population size, models with accelerating growth result in less overall variation and slower linkage disequilibrium decay compared to models with exponential growth. We also find that pairwise linkage disequilibrium of very rare variants contains information about growth rates in the recent past. Finally, we demonstrate that models of accelerating growth may substantially change estimates of present-day effective population sizes and growth times.

Potential for the evolution of heavy metal tolerance in Bryum argenteum, a moss. I. Variation within and among populations

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

Shaw, J.; Beer, S.C.; Lutz, J.

Bryum argenteum frequently occurs in urban environments and therefore appears to have the ability to tolerate high levels of such atmospheric pollutants as lead. The presence of genetic variation for tolerance to lead was assessed within and among three populations of this species from Ithaca, New York state. Plants from these populations contained extremely different concentrations of lead and other metals, but there was little or no variation in metal tolerance among the populations. There were, however, significant differences in general vigor (growth rates across all experimental treatments) among populations. Moreover, the rural and suburban populations contained high levels ofmore » variation in vigor among haploid-sib families (families of gametophytes derived from different sporophytes). The urban population, in contrast, contained conspicuously less variation than the other two.« less

Communication variations and aircrew performance

NASA Technical Reports Server (NTRS)

Kanki, Barbara G.; Folk, Valerie G.; Irwin, Cheryl M.

1991-01-01

The relationship between communication variations and aircrew performance (high-error vs low-error performances) was investigated by analyzing the coded verbal transcripts derived from the videotape records of 18 two-person air transport crews who participated in a high-fidelity, full-mission flight simulation. The flight scenario included a task which involved abnormal operations and required the coordinated efforts of all crew members. It was found that the best-performing crews were characterized by nearly identical patterns of communication, whereas the midrange and poorer performing crews showed a great deal of heterogeneity in their speech patterns. Although some specific speech sequences can be interpreted as being more or less facilitative to the crew-coordination process, predictability appears to be the key ingredient for enhancing crew performance. Crews communicating in highly standard (hence predictable) ways were better able to coordinate their task, whereas crews characterized by multiple, nonstandard communication profiles were less effective in their performance.

Digital Daily Cycles of Individuals

NASA Astrophysics Data System (ADS)

Aledavood, Talayeh; Lehmann, Sune; Saramäki, Jari

2015-10-01

Humans, like almost all animals, are phase-locked to the diurnal cycle. Most of us sleep at night and are active through the day. Because we have evolved to function with this cycle, the circadian rhythm is deeply ingrained and even detectable at the biochemical level. However, within the broader day-night pattern, there are individual differences: e.g., some of us are intrinsically morning-active, while others prefer evenings. In this article, we look at digital daily cycles: circadian patterns of activity viewed through the lens of auto-recorded data of communication and online activity. We begin at the aggregate level, discuss earlier results, and illustrate differences between population-level daily rhythms in different media. Then we move on to the individual level, and show that there is a strong individual-level variation beyond averages: individuals typically have their distinctive daily pattern that persists in time. We conclude by discussing the driving forces behind these signature daily patterns, from personal traits (morningness/eveningness) to variation in activity level and external constraints, and outline possibilities for future research.

Language and Communication Difficulties in Juvenile Offenders

ERIC Educational Resources Information Center

Bryan, Karen; Freer, Jackie; Furlong, Cheryl

2007-01-01

Background: Studies of the prison population suggest that the numbers of prisoners with language and communication disorders is higher than that of the overall population. However, the prison population is heterogeneous and it is important to focus on specific areas of the population. This study focuses on juvenile offenders. Aims: The study aimed…

Importance of latrine communication in European rabbits shifts along a rural-to-urban gradient.

PubMed

Ziege, Madlen; Bierbach, David; Bischoff, Svenja; Brandt, Anna-Lena; Brix, Mareike; Greshake, Bastian; Merker, Stefan; Wenninger, Sandra; Wronski, Torsten; Plath, Martin

2016-06-14

Information transfer in mammalian communication networks is often based on the deposition of excreta in latrines. Depending on the intended receiver(s), latrines are either formed at territorial boundaries (between-group communication) or in core areas of home ranges (within-group communication). The relative importance of both types of marking behavior should depend, amongst other factors, on population densities and social group sizes, which tend to differ between urban and rural wildlife populations. Our study is the first to assess (direct and indirect) anthropogenic influences on mammalian latrine-based communication networks along a rural-to-urban gradient in European rabbits (Oryctolagus cuniculus) living in urban, suburban and rural areas in and around Frankfurt am Main (Germany). The proportion of latrines located in close proximity to the burrow was higher at rural study sites compared to urban and suburban ones. At rural sites, we found the largest latrines and highest latrine densities close to the burrow, suggesting that core marking prevailed. By contrast, latrine dimensions and densities increased with increasing distance from the burrow in urban and suburban populations, suggesting a higher importance of peripheral marking. Increased population densities, but smaller social group sizes in urban rabbit populations may lead to an increased importance of between-group communication and thus, favor peripheral over core marking. Our study provides novel insights into the manifold ways by which man-made habitat alterations along a rural-to-urban gradient directly and indirectly affect wildlife populations, including latrine-based communication networks.

A synthetic mammalian network to compute population borders based on engineered reciprocal cell-cell communication.

PubMed

Kolar, Katja; Wischhusen, Hanna M; Müller, Konrad; Karlsson, Maria; Weber, Wilfried; Zurbriggen, Matias D

2015-12-30

Multicellular organisms depend on the exchange of information between specialized cells. This communication is often difficult to decipher in its native context, but synthetic biology provides tools to engineer well-defined systems that allow the convenient study and manipulation of intercellular communication networks. Here, we present the first mammalian synthetic network for reciprocal cell-cell communication to compute the border between a sender/receiver and a processing cell population. The two populations communicate via L-tryptophan and interleukin-4 to highlight the population border by the production of a fluorescent protein. The sharpness of that visualized edge can be adjusted by modulating key parameters of the network. We anticipate that this network will on the one hand be a useful tool to gain deeper insights into the mechanisms of tissue formation in nature and will on the other hand contribute to our ability to engineer artificial tissues.

Rainfall effects on rare annual plants

USGS Publications Warehouse

Levine, J.M.; McEachern, A.K.; Cowan, C.

2008-01-01

Variation in climate is predicted to increase over much of the planet this century. Forecasting species persistence with climate change thus requires understanding of how populations respond to climate variability, and the mechanisms underlying this response. Variable rainfall is well known to drive fluctuations in annual plant populations, yet the degree to which population response is driven by between-year variation in germination cueing, water limitation or competitive suppression is poorly understood.We used demographic monitoring and population models to examine how three seed banking, rare annual plants of the California Channel Islands respond to natural variation in precipitation and their competitive environments. Island plants are particularly threatened by climate change because their current ranges are unlikely to overlap regions that are climatically favourable in the future.Species showed 9 to 100-fold between-year variation in plant density over the 5–12 years of censusing, including a severe drought and a wet El Niño year. During the drought, population sizes were low for all species. However, even in non-drought years, population sizes and per capita growth rates showed considerable temporal variation, variation that was uncorrelated with total rainfall. These population fluctuations were instead correlated with the temperature after the first major storm event of the season, a germination cue for annual plants.Temporal variation in the density of the focal species was uncorrelated with the total vegetative cover in the surrounding community, suggesting that variation in competitive environments does not strongly determine population fluctuations. At the same time, the uncorrelated responses of the focal species and their competitors to environmental variation may favour persistence via the storage effect.Population growth rate analyses suggested differential endangerment of the focal annuals. Elasticity analyses and life table response experiments indicated that variation in germination has the same potential as the seeds produced per germinant to drive variation in population growth rates, but only the former was clearly related to rainfall.Synthesis. Our work suggests that future changes in the timing and temperatures associated with the first major rains, acting through germination, may more strongly affect population persistence than changes in season-long rainfall.

The spatial patterns of directional phenotypic selection.

PubMed

Siepielski, Adam M; Gotanda, Kiyoko M; Morrissey, Michael B; Diamond, Sarah E; DiBattista, Joseph D; Carlson, Stephanie M

2013-11-01

Local adaptation, adaptive population divergence and speciation are often expected to result from populations evolving in response to spatial variation in selection. Yet, we lack a comprehensive understanding of the major features that characterise the spatial patterns of selection, namely the extent of variation among populations in the strength and direction of selection. Here, we analyse a data set of spatially replicated studies of directional phenotypic selection from natural populations. The data set includes 60 studies, consisting of 3937 estimates of selection across an average of five populations. We performed meta-analyses to explore features characterising spatial variation in directional selection. We found that selection tends to vary mainly in strength and less in direction among populations. Although differences in the direction of selection occur among populations they do so where selection is often weakest, which may limit the potential for ongoing adaptive population divergence. Overall, we also found that spatial variation in selection appears comparable to temporal (annual) variation in selection within populations; however, several deficiencies in available data currently complicate this comparison. We discuss future research needs to further advance our understanding of spatial variation in selection. © 2013 John Wiley & Sons Ltd/CNRS.

Variations on the Use of a Pictorial Alternative Communication System with a Child with Autism and Developmental Delays

ERIC Educational Resources Information Center

Ganz, Jennifer B.; Cook, Katherine E.; Corbin-Newsome, Jawanda; Bourgeois, Bethany; Flores, Margaret

2005-01-01

As aberrant behavior is often recognized as the number one form of communication, it becomes imperative that as parents, teachers, and educators we must address and systematically teach or provide all children with an effective means of communication. While many augmentative and alternative communication systems such as manual sign language and…

Allozyme and RAPD Analysis of the Genetic Diversity and Geographic Variation in Wild Populations of the American Chestnut (Fagaceae)

Treesearch

Hongwen Huang; Fenny Dane; Thomas L. Kubisiak

1998-01-01

Genetic variation among 12 populations of the American chestnut (Custanea dentata) was investigated. Population genetic parameters estimated from allozyme variation suggest that C. dentata at both the population and species level has narrow genetic diversity as compared to other species in the genus. Average expected heterozygosity...

Spatiotemporal variation in local adaptation of a specialist insect herbivore to its long-lived host plant.

PubMed

Kalske, Aino; Leimu, Roosa; Scheepens, J F; Mutikainen, Pia

2016-09-01

Local adaptation of interacting species to one another indicates geographically variable reciprocal selection. This process of adaptation is central in the organization and maintenance of genetic variation across populations. Given that the strength of selection and responses to it often vary in time and space, the strength of local adaptation should in theory vary between generations and among populations. However, such spatiotemporal variation has rarely been explicitly demonstrated in nature and local adaptation is commonly considered to be relatively static. We report persistent local adaptation of the short-lived herbivore Abrostola asclepiadis to its long-lived host plant Vincetoxicum hirundinaria over three successive generations in two studied populations and considerable temporal variation in local adaptation in six populations supporting the geographic mosaic theory. The observed variation in local adaptation among populations was best explained by geographic distance and population isolation, suggesting that gene flow reduces local adaptation. Changes in herbivore population size did not conclusively explain temporal variation in local adaptation. Our results also imply that short-term studies are likely to capture only a part of the existing variation in local adaptation. © 2016 The Author(s). Evolution © 2016 The Society for the Study of Evolution.

Effective Health Risk Communication About Pandemic Influenza for Vulnerable Populations

PubMed Central

Tinker, Timothy

2009-01-01

The consequences of pandemic influenza for vulnerable populations will depend partly on the effectiveness of health risk communications. Strategic planning should fully consider how life circumstances, cultural values, and perspectives on risk influence behavior during a pandemic. We summarize recent scientific evidence on communication challenges and examine how sociocultural, economic, psychological, and health factors can jeopardize or facilitate public health interventions that require a cooperative public. If ignored, current communication gaps for vulnerable populations could result in unequal protection across society during an influenza pandemic. We offer insights on communication preparedness gleaned from scientific studies and the deliberations of public health experts at a meeting convened by the Centers for Disease Control and Prevention, May 1 and 2, 2008. PMID:19797744

Population-Based Resequencing of Experimentally Evolved Populations Reveals the Genetic Basis of Body Size Variation in Drosophila melanogaster

PubMed Central

Turner, Thomas L.; Stewart, Andrew D.; Fields, Andrew T.; Rice, William R.; Tarone, Aaron M.

2011-01-01

Body size is a classic quantitative trait with evolutionarily significant variation within many species. Locating the alleles responsible for this variation would help understand the maintenance of variation in body size in particular, as well as quantitative traits in general. However, successful genome-wide association of genotype and phenotype may require very large sample sizes if alleles have low population frequencies or modest effects. As a complementary approach, we propose that population-based resequencing of experimentally evolved populations allows for considerable power to map functional variation. Here, we use this technique to investigate the genetic basis of natural variation in body size in Drosophila melanogaster. Significant differentiation of hundreds of loci in replicate selection populations supports the hypothesis that the genetic basis of body size variation is very polygenic in D. melanogaster. Significantly differentiated variants are limited to single genes at some loci, allowing precise hypotheses to be formed regarding causal polymorphisms, while other significant regions are large and contain many genes. By using significantly associated polymorphisms as a priori candidates in follow-up studies, these data are expected to provide considerable power to determine the genetic basis of natural variation in body size. PMID:21437274

Population subdivision and molecular sequence variation: theory and analysis of Drosophila ananassae data.

PubMed

Vogl, Claus; Das, Aparup; Beaumont, Mark; Mohanty, Sujata; Stephan, Wolfgang

2003-11-01

Population subdivision complicates analysis of molecular variation. Even if neutrality is assumed, three evolutionary forces need to be considered: migration, mutation, and drift. Simplification can be achieved by assuming that the process of migration among and drift within subpopulations is occurring fast compared to mutation and drift in the entire population. This allows a two-step approach in the analysis: (i) analysis of population subdivision and (ii) analysis of molecular variation in the migrant pool. We model population subdivision using an infinite island model, where we allow the migration/drift parameter Theta to vary among populations. Thus, central and peripheral populations can be differentiated. For inference of Theta, we use a coalescence approach, implemented via a Markov chain Monte Carlo (MCMC) integration method that allows estimation of allele frequencies in the migrant pool. The second step of this approach (analysis of molecular variation in the migrant pool) uses the estimated allele frequencies in the migrant pool for the study of molecular variation. We apply this method to a Drosophila ananassae sequence data set. We find little indication of isolation by distance, but large differences in the migration parameter among populations. The population as a whole seems to be expanding. A population from Bogor (Java, Indonesia) shows the highest variation and seems closest to the species center.

A Transactional Model of Spoken Vocabulary Variation in Toddlers with Intellectual Disabilities

ERIC Educational Resources Information Center

Woynaroski, Tiffany; Yoder, Paul J.; Fey, Marc E.; Warren, Steven F.

2014-01-01

Purpose: The authors examined (a) whether dose frequency of milieu communication teaching (MCT) affects children's canonical syllabic communication and (b) whether the relation between early canonical syllabic communication and later spoken vocabulary is mediated by parental linguistic mapping in children with intellectual disabilities (ID).…

Linking Gestures: Cross-Cultural Variation during Instructional Analogies

ERIC Educational Resources Information Center

Richland, Lindsey Engle

2015-01-01

Deictic linking gestures, hand and arm motions that physically embody links being communicated between two or more objects in the shared communicative environment, are explored in a cross-cultural sample of mathematics instruction. Linking gestures are specifically examined here when they occur in the context of communicative analogies designed to…

Selective Pressures Explain Differences in Flower Color among Gentiana lutea Populations.

PubMed

Sobral, Mar; Veiga, Tania; Domínguez, Paula; Guitián, Javier A; Guitián, Pablo; Guitián, José M

2015-01-01

Flower color variation among plant populations might reflect adaptation to local conditions such as the interacting animal community. In the northwest Iberian Peninsula, flower color of Gentiana lutea varies longitudinally among populations, ranging from orange to yellow. We explored whether flower color is locally adapted and the role of pollinators and seed predators as agents of selection by analyzing the influence of flower color on (i) pollinator visitation rate and (ii) escape from seed predation and (iii) by testing whether differences in pollinator communities correlate with flower color variation across populations. Finally, (iv) we investigated whether variation in selective pressures explains flower color variation among 12 G. lutea populations. Flower color influenced pollinator visits and differences in flower color among populations were related to variation in pollinator communities. Selective pressures on flower color vary among populations and explain part of flower color differences among populations of G. lutea. We conclude that flower color in G. lutea is locally adapted and that pollinators play a role in this adaptation.

Selective Pressures Explain Differences in Flower Color among Gentiana lutea Populations

PubMed Central

Domínguez, Paula; Guitián, Javier A.; Guitián, Pablo; Guitián, José M.

2015-01-01

Flower color variation among plant populations might reflect adaptation to local conditions such as the interacting animal community. In the northwest Iberian Peninsula, flower color of Gentiana lutea varies longitudinally among populations, ranging from orange to yellow. We explored whether flower color is locally adapted and the role of pollinators and seed predators as agents of selection by analyzing the influence of flower color on (i) pollinator visitation rate and (ii) escape from seed predation and (iii) by testing whether differences in pollinator communities correlate with flower color variation across populations. Finally, (iv) we investigated whether variation in selective pressures explains flower color variation among 12 G. lutea populations. Flower color influenced pollinator visits and differences in flower color among populations were related to variation in pollinator communities. Selective pressures on flower color vary among populations and explain part of flower color differences among populations of G. lutea. We conclude that flower color in G. lutea is locally adapted and that pollinators play a role in this adaptation. PMID:26172378

Sociodemographic variations in communication on sexuality and HIV/AIDS with parents, family members and teachers among in-school adolescents: a multi-site study in Tanzania and South Africa.

PubMed

Namisi, Francis Sande; Flisher, Alan J; Overland, Simon; Bastien, Sheri; Onya, Hans; Kaaya, Sylvia; Aarø, Leif Edvard

2009-06-01

To identify with whom in-school adolescents preferred to communicate about sexuality, and to study adolescents' communication on HIV/AIDS, abstinence and condoms with parents/guardians, other adult family members, and teachers. Data were obtained from a baseline questionnaire survey carried out in South Africa (Cape Town and Mankweng) and Tanzania (Dar es Salaam) in early 2004. We analysed data for 14,944 adolescents from 80 randomly selected schools. The mean ages were as follows: Cape Town, 13.38 years (standard deviation (SD) 1.15); Mankweng, 13.94 years (SD 1.35); and Dar es Salaam, 12.94 years (SD 1.31). Adolescent females preferred to receive sexuality information from their mothers, while among males there was a higher preference for fathers in two sites. Thirty-seven per cent, 41% and 29% reported never or hardly ever communicating about sexuality with parents, other adult family members, and teachers, respectively. "Silence'' was more prevalent in Dar es Salaam than in the other two sites. The odds of "never or hardly ever'' communicating with parents in Dar es Salaam were higher among girls than among boys (p < 0.01). For the two South African sites, boys had significantly higher odds of experiencing silence than did girls (both p < 0.001), and socioeconomic status was positively associated with parent-adolescent sexuality communication. In the logistic regression models, explained variation (Nagelkerke's R(2)) across sites ranged from 0.013 to 0.032. In all three sites, a substantial proportion of adolescents reported not communicating with their parents about HIV/AIDS, abstinence, or condoms. The low proportion of explained variation in sexuality communication implies that silence is common across sociodemographic subgroups.

Morphological and genetic divergence in Swedish postglacial stickleback (Pungitius pungitius) populations

PubMed Central

2011-01-01

Background An important objective of evolutionary biology is to understand the processes that govern phenotypic variation in natural populations. We assessed patterns of morphological and genetic divergence among coastal and inland lake populations of nine-spined stickleback in northern Sweden. Coastal populations are either from the Baltic coast (n = 5) or from nearby coastal lakes (n = 3) that became isolated from the Baltic Sea (< 100 years before present, ybp). Inland populations are from freshwater lakes that became isolated from the Baltic approximately 10,000 ybp; either single species lakes without predators (n = 5), or lakes with a recent history of predation (n = 5) from stocking of salmonid predators (~50 ybp). Results Coastal populations showed little variation in 11 morphological traits and had longer spines per unit of body length than inland populations. Inland populations were larger, on average, and showed greater morphological variation than coastal populations. A principal component analysis (PCA) across all populations revealed two major morphological axes related to spine length (PC1, 47.7% variation) and body size (PC2, 32.9% variation). Analysis of PCA scores showed marked similarity in coastal (Baltic coast and coastal lake) populations. PCA scores indicate that inland populations with predators have higher within-group variance in spine length and lower within-group variance in body size than inland populations without predators. Estimates of within-group PST (a proxy for QST) from PCA scores are similar to estimates of FST for coastal lake populations but PST >FST for Baltic coast populations. PST >FST for PC1 and PC2 for inland predator and inland no predator populations, with the exception that PST

Variations analysis of NLGN3 and NLGN4X gene in Chinese autism patients.

PubMed

Xu, Xiaojuan; Xiong, Zhimin; Zhang, Lusi; Liu, Yalan; Lu, Lina; Peng, Yu; Guo, Hui; Zhao, Jingping; Xia, Kun; Hu, Zhengmao

2014-06-01

Autism is a neurodevelopmental disorder clinically characterized by impairment of social interaction, deficits in verbal communication, as well as stereotypic and repetitive behaviors. Several studies have implicated that abnormal synaptogenesis was involved in the incidence of autism. Neuroligins are postsynaptic cell adhesion molecules and interacted with neurexins to regulate the fine balance between excitation and inhibition of synapses. Recently, mutation analysis, cellular and mice models hinted neuroligin mutations probably affected synapse maturation and function. In this study, four missense variations [p.G426S (NLGN3), p.G84R (NLGN4X), p.Q162 K (NLGN4X) and p.A283T (NLGN4X)] in four different unrelated patients have been identified by PCR and direct sequencing. These four missense variations were absent in the 453 controls and have not been reported in 1000 Genomes Project. Bioinformatic analysis of the four missense variations revealed that p.G84R and p.A283T were "Probably Damaging". The variations may cause abnormal synaptic homeostasis and therefore trigger the patients more predisposed to autism. By case-control analysis, we identified the common SNPs (rs3747333 and rs3747334) in the NLGN4X gene significantly associated with risk for autism [p = 5.09E-005; OR 4.685 (95% CI 2.073-10.592)]. Our data provided a further evidence for the involvement of NLGN3 and NLGN4X gene in the pathogenesis of autism in Chinese population.

On The Evolutionary Origin of Symbolic Communication

NASA Astrophysics Data System (ADS)

Grouchy, Paul; D'Eleuterio, Gabriele M. T.; Christiansen, Morten H.; Lipson, Hod

2016-10-01

The emergence of symbolic communication is often cited as a critical step in the evolution of Homo sapiens, language, and human-level cognition. It is a widely held assumption that humans are the only species that possess natural symbolic communication schemes, although a variety of other species can be taught to use symbols. The origin of symbolic communication remains a controversial open problem, obfuscated by the lack of a fossil record. Here we demonstrate an unbroken evolutionary pathway from a population of initially noncommunicating robots to the spontaneous emergence of symbolic communication. Robots evolve in a simulated world and are supplied with only a single channel of communication. When their ability to reproduce is motivated by the need to find a mate, robots evolve indexical communication schemes from initially noncommunicating populations in 99% of all experiments. Furthermore, 9% of the populations evolve a symbolic communication scheme allowing pairs of robots to exchange information about two independent spatial dimensions over a one-dimensional channel, thereby increasing their chance of reproduction. These results suggest that the ability for symbolic communication could have emerged spontaneously under natural selection, without requiring cognitive preadaptations or preexisting iconic communication schemes as previously conjectured.

Autism, language and communication in children with sex chromosome trisomies

PubMed Central

Bishop, Dorothy V M; Jacobs, Patricia A; Lachlan, Katherine; Wellesley, Diana; Barnicoat, Angela; Boyd, Patricia A; Fryer, Alan; Middlemiss, Prisca; Smithson, Sarah; Metcalfe, Kay; Shears, Deborah; Leggett, Victoria; Nation, Kate; Scerif, Gaia

2011-01-01

Purpose Sex chromosome trisomies (SCTs) are found on amniocentesis in 2.3–3.7 per 1000 same-sex births, yet there is a limited database on which to base a prognosis. Autism has been described in postnatally diagnosed cases of Klinefelter syndrome (XXY karyotype), but the prevalence in non-referred samples, and in other trisomies, is unclear. The authors recruited the largest sample including all three SCTs to be reported to date, including children identified on prenatal screening, to clarify this issue. Design Parents of children with a SCT were recruited either via prenatal screening or via a parental support group, to give a sample of 58 XXX, 19 XXY and 58 XYY cases. Parents were interviewed using the Vineland Adaptive Behavior Scales and completed questionnaires about the communicative development of children with SCTs and their siblings (42 brothers and 26 sisters). Results Rates of language and communication problems were high in all three trisomies. Diagnoses of autism spectrum disorder (ASD) were found in 2/19 cases of XXY (11%) and 11/58 XYY (19%). After excluding those with an ASD diagnosis, communicative profiles indicative of mild autistic features were common, although there was wide individual variation. Conclusions Autistic features have not previously been remarked upon in studies of non-referred samples with SCTs, yet the rate is substantially above population levels in this sample, even when attention is restricted to early-identified cases. The authors hypothesise that X-linked and Y-linked neuroligins may play a significant role in the aetiology of communication impairments and ASD. PMID:20656736

Survey Shows Variation in Ph.D. Methods Training.

ERIC Educational Resources Information Center

Steeves, Leslie; And Others

1983-01-01

Reports on a 1982 survey of journalism graduate studies indicating considerable variation in research methods requirements and emphases in 23 universities offering doctoral degrees in mass communication. (HOD)

Functional implications of Major Histocompatibility (MH) variation using estuarine fish populations.

PubMed

Cohen, Sarah; Tirindelli, Joëlle; Gomez-Chiarri, Marta; Nacci, Diane

2006-12-01

Recently, there has been a dramatic expansion of studies of major histocompatibility complex (MHC) variation aimed at discovering functional differences in immunity across wild populations of diverse vertebrate species. Some species with relatively low genetic diversity or under strong directional selection by pathogens have revealed fascinating cases of MHC allelic disease linkage. More generally in genetically diverse species, however, these linkages may be hard to find. In this paper, we review approaches for assessing functional variation in MHC and discuss their potential use for discovering smaller-scale intraspecific spatial and temporal patterns of MHC variation. Then, we describe and illustrate an approach using the structural model to produce a population composite of variation in antigen-binding regions by mapping population-specific substitutions onto functional regions of the molecule. We are producing models of variation in major histocompatibility (MH) loci for populations of non-migratory fish (killifish, Fundulus heteroclitus) resident at sites that vary dramatically in environmental quality. We discuss the goal of relating MH population variation to functional differences in disease susceptibility such as those inferred by observations of parasitic infection and direct measurement of bacterial challenges in the laboratory. Our study has focused on relatively well-studied killifish populations, including those resident in a highly disturbed, chemically contaminated estuary and nearby less contaminated sites. Population-specific genetic changes at MHC antigen-binding loci are described, and evidence relevant to functional implications of these changes is reviewed. Population-specific patterns of variation in antigen-binding regions in combination with a range of assessments of immune function will provide a powerful new approach to reveal functional changes in MHC.

Information, Education, Communication in Population.

ERIC Educational Resources Information Center

Hawaii Univ., Honolulu. East-West Center.

Programs and services of the Swedish International Development Authority (SIDA) are reviewed in this report on resources available for the support of population information, education, and communication activities. Four major sections describe in concise, outline form: (1) the agency and its programs, (2) the specific program in population/family…

Genetic variation within and among populations of Rhodiola alsia (Crassulaceae) native to the Tibetan Plateau as detected by ISSR markers.

PubMed

Xia, Tao; Chen, Shilong; Chen, Shengyun; Ge, Xuejun

2005-04-01

Genetic variation of 10 Rhodiola alsia (Crassulaceae) populations from the Qinghai-Tibet Plateau of China was investigated using intersimple sequence repeat (ISSR) markers. R. alsia is an endemic species of the Qinghai-Tibet Plateau. Of the 100 primers screened, 13 were highly polymorphic. Using these primers, 140 discernible DNA fragments were generated with 112 (80%) being polymorphic, indicating pronounced genetic variation at the species level. Also there were high levels of polymorphism at the population level with the percentage of polymorphic bands (PPB) ranging from 63.4 to 88.6%. Analysis of molecular variance (AMOVA) showed that the genetic variation was mainly found among populations (70.3%) and variance within populations was 29.7%. The main factors responsible for the high level of differentiation among populations are probably the isolation from other populations and clonal propagation of this species. Occasional sexual reproduction might occur in order to maintain high levels of variation within populations. Environmental conditions could also influence population genetic structure as they occur in severe habitats. The strong genetic differentiation among populations in our study indicates that the conservation of genetic variability in R. alsia requires maintenance of as many populations as possible.

Directional selection effects on patterns of phenotypic (co)variation in wild populations

PubMed Central

Patton, J. L.; Hubbe, A.; Marroig, G.

2016-01-01

Phenotypic (co)variation is a prerequisite for evolutionary change, and understanding how (co)variation evolves is of crucial importance to the biological sciences. Theoretical models predict that under directional selection, phenotypic (co)variation should evolve in step with the underlying adaptive landscape, increasing the degree of correlation among co-selected traits as well as the amount of genetic variance in the direction of selection. Whether either of these outcomes occurs in natural populations is an open question and thus an important gap in evolutionary theory. Here, we documented changes in the phenotypic (co)variation structure in two separate natural populations in each of two chipmunk species (Tamias alpinus and T. speciosus) undergoing directional selection. In populations where selection was strongest (those of T. alpinus), we observed changes, at least for one population, in phenotypic (co)variation that matched theoretical expectations, namely an increase of both phenotypic integration and (co)variance in the direction of selection and a re-alignment of the major axis of variation with the selection gradient. PMID:27881744

Differential influences of local subpopulations on regional diversity and differentiation for greater sage-grouse (Centrocercus urophasianus)

USGS Publications Warehouse

Row, Jeffery R.; Oyler-McCance, Sara J.; Fedy, Brad C.

2016-01-01

The distribution of spatial genetic variation across a region can shape evolutionary dynamics and impact population persistence. Local population dynamics and among-population dispersal rates are strong drivers of this spatial genetic variation, yet for many species we lack a clear understanding of how these population processes interact in space to shape within-species genetic variation. Here, we used extensive genetic and demographic data from 10 subpopulations of greater sage-grouse to parameterize a simulated approximate Bayesian computation (ABC) model and (i) test for regional differences in population density and dispersal rates for greater sage-grouse subpopulations in Wyoming, and (ii) quantify how these differences impact subpopulation regional influence on genetic variation. We found a close match between observed and simulated data under our parameterized model and strong variation in density and dispersal rates across Wyoming. Sensitivity analyses suggested that changes in dispersal (via landscape resistance) had a greater influence on regional differentiation, whereas changes in density had a greater influence on mean diversity across all subpopulations. Local subpopulations, however, varied in their regional influence on genetic variation. Decreases in the size and dispersal rates of central populations with low overall and net immigration (i.e. population sources) had the greatest negative impact on genetic variation. Overall, our results provide insight into the interactions among demography, dispersal and genetic variation and highlight the potential of ABC to disentangle the complexity of regional population dynamics and project the genetic impact of changing conditions.

How Do Low-Literacy Populations Perceive "Dirty Bombs"? Implications for Preparedness Messages.

PubMed

Bass, Sarah Bauerle; Gordon, Thomas F; Maurer, Laurie; Greener, Judith; Mora, Gabriella; Ruggieri, Dominique; Wolak, Caitlin; Parvanta, Claudia

2016-01-01

Potential terror events such as "dirty bombs" could have significant public health effects, but little is known about how low-literacy populations perceive dirty bombs, their trust in public health or government officials to provide credible information, and their willingness to comply with recommended actions. We surveyed 50 low-literacy adults from a large urban center; they were mostly members of ethnic minority groups. We used unique social marketing methods-perceptual mapping and vector message modeling-to create 3-dimensional models that reflected respondents' knowledge of what a dirty bomb is, their intended behaviors should one occur, and their concerns about complying with "shelter in place" recommendations. To further understand individual variations in this at-risk group, a k-means cluster analysis was used to identify 3 distinct segments, differing on trust of local authorities and their emergency response, willingness to comply with emergency directives, and trust of information sources. Message strategies targeting each segment were developed to focus on concepts important to moving the groups toward a "shelter in place" behavior, revealing key differences in how best to communicate with risk communication. We discuss how these methods helped elucidate specific differences in each segment's understanding of and likely response during the event of a "dirty bomb" and how these techniques can be used to create more effective message strategies targeted to these groups.

How Do Low-Literacy Populations Perceive “Dirty Bombs”? Implications for Preparedness Messages

PubMed Central

Gordon, Thomas F.; Maurer, Laurie; Greener, Judith; Mora, Gabriella; Ruggieri, Dominique; Wolak, Caitlin; Parvanta, Claudia

2016-01-01

Potential terror events such as “dirty bombs” could have significant public health effects, but little is known about how low-literacy populations perceive dirty bombs, their trust in public health or government officials to provide credible information, and their willingness to comply with recommended actions. We surveyed 50 low-literacy adults from a large urban center; they were mostly members of ethnic minority groups. We used unique social marketing methods—perceptual mapping and vector message modeling—to create 3-dimensional models that reflected respondents' knowledge of what a dirty bomb is, their intended behaviors should one occur, and their concerns about complying with “shelter in place” recommendations. To further understand individual variations in this at-risk group, a k-means cluster analysis was used to identify 3 distinct segments, differing on trust of local authorities and their emergency response, willingness to comply with emergency directives, and trust of information sources. Message strategies targeting each segment were developed to focus on concepts important to moving the groups toward a “shelter in place” behavior, revealing key differences in how best to communicate with risk communication. We discuss how these methods helped elucidate specific differences in each segment's understanding of and likely response during the event of a “dirty bomb” and how these techniques can be used to create more effective message strategies targeted to these groups. PMID:27584855

Premating isolation is determined by larval rearing substrates in cactophilic Drosophila mojavensis. IX. Host plant and population specific epicuticular hydrocarbon expression influences mate choice and sexual selection.

PubMed

Havens, J A; Etges, W J

2013-03-01

Sexual signals in cactophilic Drosophila mojavensis include cuticular hydrocarbons (CHCs), contact pheromones that mediate female discrimination of males during courtship. CHCs, along with male courtship songs, cause premating isolation between diverged populations, and are influenced by genotype × environment interactions caused by different host cacti. CHC profiles of mated and unmated adult flies from a Baja California and a mainland Mexico population of D. mojavensis reared on two host cacti were assayed to test the hypothesis that male CHCs mediate within-population female discrimination of males. In multiple choice courtship trials, mated and unmated males differed in CHC profiles, indicating that females prefer males with particular blends of CHCs. Mated and unmated females significantly differed in CHC profiles as well. Adults in the choice trials had CHC profiles that were significantly different from those in pair-mated adults from no-choice trials revealing an influence of sexual selection. Females preferred different male CHC blends in each population, but the influence of host cactus on CHC variation was significant only in the mainland population indicating population-specific plasticity in CHCs. Different groups of CHCs mediated female choice-based sexual selection in each population suggesting that geographical and ecological divergence has the potential to promote divergence in mate communication systems. © 2012 The Authors. Journal of Evolutionary Biology © 2012 European Society For Evolutionary Biology.

Effects of temporal variation in temperature and density dependence on insect population dynamics

USDA-ARS?s Scientific Manuscript database

Understanding effects of environmental variation on insect populations is important in light of predictions about increasing future climatic variability. In order to understand the effects of changing environmental variation on population dynamics and life history evolution in insects one would need...

Multilingualism and Affordances: Variation in Self-Perceived Communicative Competence and Communicative Anxiety in French L1, L2, L3 and L4

ERIC Educational Resources Information Center

Dewaele, Jean-Marc

2010-01-01

In this contribution, I investigate the effect of the knowledge of other languages on self-perceived communicative competence and communicative anxiety in the French of 953 users. I tested the hypothesis that knowledge of more languages, specifically other Romance languages, create stronger or clearer affordances (Singleton & Aronin, Innovation in…

Genetic variation in heat-stress tolerance among South American Drosophila populations.

PubMed

Fallis, Lindsey C; Fanara, Juan Jose; Morgan, Theodore J

2011-10-01

Spatial or temporal differences in environmental variables, such as temperature, are ubiquitous in nature and impose stress on organisms. This is especially true for organisms that are isothermal with the environment, such as insects. Understanding the means by which insects respond to temperature and how they will react to novel changes in environmental temperature is important for understanding the adaptive capacity of populations and to predict future trajectories of evolutionary change. The organismal response to heat has been identified as an important environmental variable for insects that can dramatically influence life history characters and geographic range. In the current study we surveyed the amount of variation in heat tolerance among Drosophila melanogaster populations collected at diverse sites along a latitudinal gradient in Argentina (24°-38°S). This is the first study to quantify heat tolerance in South American populations and our work demonstrates that most of the populations surveyed have abundant within-population phenotypic variation, while still exhibiting significant variation among populations. The one exception was the most heat tolerant population that comes from a climate exhibiting the warmest annual mean temperature. All together our results suggest there is abundant genetic variation for heat-tolerance phenotypes within and among natural populations of Drosophila and this variation has likely been shaped by environmental temperature.

Geographical Variation in Egg Mass and Egg Content in a Passerine Bird

PubMed Central

Ruuskanen, Suvi; Siitari, Heli; Eeva, Tapio; Belskii, Eugen; Järvinen, Antero; Kerimov, Anvar; Krams, Indrikis; Moreno, Juan; Morosinotto, Chiara; Mänd, Raivo; Möstl, Erich; Orell, Markku; Qvarnström, Anna; Salminen, Juha-Pekka; Slater, Fred; Tilgar, Vallo; Visser, Marcel E.; Winkel, Wolfgang; Zang, Herwig; Laaksonen, Toni

2011-01-01

Reproductive, phenotypic and life-history traits in many animal and plant taxa show geographic variation, indicating spatial variation in selection regimes. Maternal deposition to avian eggs, such as hormones, antibodies and antioxidants, critically affect development of the offspring, with long-lasting effects on the phenotype and fitness. Little is however known about large-scale geographical patterns of variation in maternal deposition to eggs. We studied geographical variation in egg components of a passerine bird, the pied flycatcher (Ficedula hypoleuca), by collecting samples from 16 populations and measuring egg and yolk mass, albumen lysozyme activity, yolk immunoglobulins, yolk androgens and yolk total carotenoids. We found significant variation among populations in most egg components, but ca. 90% of the variation was among individuals within populations. Population however explained 40% of the variation in carotenoid levels. In contrast to our hypothesis, we found geographical trends only in carotenoids, but not in any of the other egg components. Our results thus suggest high within-population variation and leave little scope for local adaptation and genetic differentiation in deposition of different egg components. The role of these maternally-derived resources in evolutionary change should be further investigated. PMID:22110579

Using Commercial Resources in Population Communications Programs.

ERIC Educational Resources Information Center

Sweeney, William O.

The author defines populations communications as all information, education, and other activities which can produce changes in attitudes and behavior towards contraception, family planning, and population growth. He discusses in this paper the effort made in 27 nations to utilize commercial, profit-making goods and services for the purpose of…

Communications in public health emergency preparedness: a systematic review of the literature.

PubMed

Savoia, Elena; Lin, Leesa; Viswanath, Kasisomayajula

2013-09-01

During a public health crisis, public health agencies engage in a variety of public communication efforts to inform the population, encourage the adoption of preventive behaviors, and limit the impact of adverse events. Given the importance of communication to the public in public health emergency preparedness, it is critical to examine the extent to which this field of study has received attention from the scientific community. We conducted a systematic literature review to describe current research in the area of communication to the public in public health emergency preparedness, focusing on the association between sociodemographic and behavioral factors and communication as well as preparedness outcomes. Articles were searched in PubMed and Embase and reviewed by 2 independent reviewers. A total of 131 articles were included for final review. Fifty-three percent of the articles were empirical, of which 74% were population-based studies, and 26% used information environment analysis techniques. None had an experimental study design. Population-based studies were rarely supported by theoretical models and mostly relied on a cross-sectional study design. Consistent results were reported on the association between population socioeconomic factors and public health emergency preparedness communication and preparedness outcomes. Our findings show the need for empirical research to determine what type of communication messages can be effective in achieving preparedness outcomes across various population groups. They suggest that a real-time analysis of the information environment is valuable in knowing what is being communicated to the public and could be used for course correction of public health messages during a crisis.

Communications in Public Health Emergency Preparedness: A Systematic Review of the Literature

PubMed Central

Savoia, Elena; Viswanath, Kasisomayajula

2013-01-01

During a public health crisis, public health agencies engage in a variety of public communication efforts to inform the population, encourage the adoption of preventive behaviors, and limit the impact of adverse events. Given the importance of communication to the public in public health emergency preparedness, it is critical to examine the extent to which this field of study has received attention from the scientific community. We conducted a systematic literature review to describe current research in the area of communication to the public in public health emergency preparedness, focusing on the association between sociodemographic and behavioral factors and communication as well as preparedness outcomes. Articles were searched in PubMed and Embase and reviewed by 2 independent reviewers. A total of 131 articles were included for final review. Fifty-three percent of the articles were empirical, of which 74% were population-based studies, and 26% used information environment analysis techniques. None had an experimental study design. Population-based studies were rarely supported by theoretical models and mostly relied on a cross-sectional study design. Consistent results were reported on the association between population socioeconomic factors and public health emergency preparedness communication and preparedness outcomes. Our findings show the need for empirical research to determine what type of communication messages can be effective in achieving preparedness outcomes across various population groups. They suggest that a real-time analysis of the information environment is valuable in knowing what is being communicated to the public and could be used for course correction of public health messages during a crisis. PMID:24041193

Low worldwide genetic diversity in the killer whale (Orcinus orca): implications for demographic history.

PubMed Central

Hoelzel, A Rus; Natoli, Ada; Dahlheim, Marilyn E; Olavarria, Carlos; Baird, Robin W; Black, Nancy A

2002-01-01

A low level of genetic variation in mammalian populations where the census population size is relatively large has been attributed to various factors, such as a naturally small effective population size, historical bottlenecks and social behaviour. The killer whale (Orcinus orca) is an abundant, highly social species with reduced genetic variation. We find no consistent geographical pattern of global diversity and no mtDNA variation within some regional populations. The regional lack of variation is likely to be due to the strict matrilineal expansion of local populations. The worldwide pattern and paucity of diversity may indicate a historical bottleneck as an additional factor. PMID:12137576

Risk Assessment and Communication Tools for Genotype Associations with Multifactorial Phenotypes: The Concept of “Edge Effect” and Cultivating an Ethical Bridge between Omics Innovations and Society

PubMed Central

Suarez-Kurtz, Guilherme; Stenne, Raphaëlle; Somogyi, Andrew A.; Someya, Toshiyuki; Kayaalp, S. Oğuz; Kolker, Eugene

2009-01-01

Abstract Applications of omics technologies in the postgenomics era swiftly expanded from rare monogenic disorders to multifactorial common complex diseases, pharmacogenomics, and personalized medicine. Already, there are signposts indicative of further omics technology investment in nutritional sciences (nutrigenomics), environmental health/ecology (ecogenomics), and agriculture (agrigenomics). Genotype–phenotype association studies are a centerpiece of translational research in omics science. Yet scientific and ethical standards and ways to assess and communicate risk information obtained from association studies have been neglected to date. This is a significant gap because association studies decisively influence which genetic loci become genetic tests in the clinic or products in the genetic test marketplace. A growing challenge concerns the interpretation of large overlap typically observed in distribution of quantitative traits in a genetic association study with a polygenic/multifactorial phenotype. To remedy the shortage of risk assessment and communication tools for association studies, this paper presents the concept of edge effect. That is, the shift in population edges of a multifactorial quantitative phenotype is a more sensitive measure (than population averages) to gauge the population level impact and by extension, policy significance of an omics marker. Empirical application of the edge effect concept is illustrated using an original analysis of warfarin pharmacogenomics and the VKORC1 genetic variation in a Brazilian population sample. These edge effect analyses are examined in relation to regulatory guidance development for association studies. We explain that omics science transcends the conventional laboratory bench space and includes a highly heterogeneous cast of stakeholders in society who have a plurality of interests that are often in conflict. Hence, communication of risk information in diagnostic medicine also demands attention to processes involved in production of knowledge and human values embedded in scientific practice, for example, why, how, by whom, and to what ends association studies are conducted, and standards are developed (or not). To ensure sustainability of omics innovations and forecast their trajectory, we need interventions to bridge the gap between omics laboratory and society. Appreciation of scholarship in history of omics science is one remedy to responsibly learn from the past to ensure a sustainable future in omics fields, both emerging (nutrigenomics, ecogenomics), and those that are more established (pharmacogenomics). Another measure to build public trust and sustainability of omics fields could be legislative initiatives to create a multidisciplinary oversight body, at arm's length from conflict of interests, to carry out independent, impartial, and transparent innovation analyses and prospective technology assessment. PMID:19290811

Risk assessment and communication tools for genotype associations with multifactorial phenotypes: the concept of "edge effect" and cultivating an ethical bridge between omics innovations and society.

PubMed

Ozdemir, Vural; Suarez-Kurtz, Guilherme; Stenne, Raphaëlle; Somogyi, Andrew A; Someya, Toshiyuki; Kayaalp, S Oğuz; Kolker, Eugene

2009-02-01

Applications of omics technologies in the postgenomics era swiftly expanded from rare monogenic disorders to multifactorial common complex diseases, pharmacogenomics, and personalized medicine. Already, there are signposts indicative of further omics technology investment in nutritional sciences (nutrigenomics), environmental health/ecology (ecogenomics), and agriculture (agrigenomics). Genotype-phenotype association studies are a centerpiece of translational research in omics science. Yet scientific and ethical standards and ways to assess and communicate risk information obtained from association studies have been neglected to date. This is a significant gap because association studies decisively influence which genetic loci become genetic tests in the clinic or products in the genetic test marketplace. A growing challenge concerns the interpretation of large overlap typically observed in distribution of quantitative traits in a genetic association study with a polygenic/multifactorial phenotype. To remedy the shortage of risk assessment and communication tools for association studies, this paper presents the concept of edge effect. That is, the shift in population edges of a multifactorial quantitative phenotype is a more sensitive measure (than population averages) to gauge the population level impact and by extension, policy significance of an omics marker. Empirical application of the edge effect concept is illustrated using an original analysis of warfarin pharmacogenomics and the VKORC1 genetic variation in a Brazilian population sample. These edge effect analyses are examined in relation to regulatory guidance development for association studies. We explain that omics science transcends the conventional laboratory bench space and includes a highly heterogeneous cast of stakeholders in society who have a plurality of interests that are often in conflict. Hence, communication of risk information in diagnostic medicine also demands attention to processes involved in production of knowledge and human values embedded in scientific practice, for example, why, how, by whom, and to what ends association studies are conducted, and standards are developed (or not). To ensure sustainability of omics innovations and forecast their trajectory, we need interventions to bridge the gap between omics laboratory and society. Appreciation of scholarship in history of omics science is one remedy to responsibly learn from the past to ensure a sustainable future in omics fields, both emerging (nutrigenomics, ecogenomics), and those that are more established (pharmacogenomics). Another measure to build public trust and sustainability of omics fields could be legislative initiatives to create a multidisciplinary oversight body, at arm's length from conflict of interests, to carry out independent, impartial, and transparent innovation analyses and prospective technology assessment.

Network analysis of team communication in a busy emergency department

PubMed Central

2013-01-01

Background The Emergency Department (ED) is consistently described as a high-risk environment for patients and clinicians that demands colleagues quickly work together as a cohesive group. Communication between nurses, physicians, and other ED clinicians is complex and difficult to track. A clear understanding of communications in the ED is lacking, which has a potentially negative impact on the design and effectiveness of interventions to improve communications. We sought to use Social Network Analysis (SNA) to characterize communication between clinicians in the ED. Methods Over three-months, we surveyed to solicit the communication relationships between clinicians at one urban academic ED across all shifts. We abstracted survey responses into matrices, calculated three standard SNA measures (network density, network centralization, and in-degree centrality), and presented findings stratified by night/day shift and over time. Results We received surveys from 82% of eligible participants and identified wide variation in the magnitude of communication cohesion (density) and concentration of communication between clinicians (centralization) by day/night shift and over time. We also identified variation in in-degree centrality (a measure of power/influence) by day/night shift and over time. Conclusions We show that SNA measurement techniques provide a comprehensive view of ED communication patterns. Our use of SNA revealed that frequency of communication as a measure of interdependencies between ED clinicians varies by day/night shift and over time. PMID:23521890

Climates Past, Present, and Yet-to-Come Shape Climate Change Vulnerabilities.

PubMed

Nadeau, Christopher P; Urban, Mark C; Bridle, Jon R

2017-10-01

Climate change is altering life at multiple scales, from genes to ecosystems. Predicting the vulnerability of populations to climate change is crucial to mitigate negative impacts. We suggest that regional patterns of spatial and temporal climatic variation scaled to the traits of an organism can predict where and why populations are most vulnerable to climate change. Specifically, historical climatic variation affects the sensitivity and response capacity of populations to climate change by shaping traits and the genetic variation in those traits. Present and future climatic variation can affect both climate change exposure and population responses. We provide seven predictions for how climatic variation might affect the vulnerability of populations to climate change and suggest key directions for future research. Copyright © 2017 Elsevier Ltd. All rights reserved.

Highlights of session presentations. TSS / CST population IEC meeting.

PubMed

1995-01-01

The great deal of documentation which was prepared for the recent TSS/CST Population IEC (information, education, and communication) meeting from research, field experiments, and action projects will be useful to TSS/CST advisors and individual countries undertaking IEC and population education work. This article summarizes the 12 sessions held during the open forum. To illustrate some of the latest trends in population and health communication, the "enter-educate" approach and use of the interactive computer software called SCOPE (Strategic Communication Planning and Evaluation) were discussed. Next, ways in which to apply research effectively in IEC and population education were considered. Examples were provided of 1) a workshop methodology used to help a multidisciplinary group design a problem-solving communication strategy in Malaysia and Dominica; 2) the counseling training evaluation technique based on the GATHER (greet, ask, tell, help, explain, and return for follow-up) model; and 3) four types of evaluation of population education in schools. The third session was concerned with the program approach used in IEC and population education. Session 4 dealt with the implication of UNFPA support to family planning (FP) IEC. Counseling skills training and interpersonal communication were next on the agenda, followed by a consideration of how knowledge and policies are applied in the area of youth. The seventh session concentrated on ways to involve men in FP and reproductive health and included a discussion of a case study on the attitude and behavior of men with regard to FP which had IEC implications. The next session described the need to reconceptualize population education and what such a reconceptualization would entail. Session 9 was devoted to a consideration of gender issues and the education of girls. The tenth session covered the use of participatory approaches and community involvement in population communication programs. Innovative methodologies for school-based population education were described next, and the last session was concerned with new information technologies such as navigating the Internet and using new software for establishing databases.

The Geography of Political Communication: Effects of Regional Variations in Campaign Advertising on Citizen Communication

ERIC Educational Resources Information Center

Cho, Jaeho

2011-01-01

This study explores whether and how campaign-induced changes in local information environments influence citizens' everyday communication activities. The empirical analysis in this study centers on a comparison of two New Jersey media markets that showed idiosyncratic differences in the amount of political advertising during the 2000 presidential…

Warning signal brightness variation: sexual selection may work under the radar of natural selection in populations of a polytypic poison frog.

PubMed

Crothers, Laura R; Cummings, Molly E

2013-05-01

Though theory predicts consistency of warning signals in aposematic species to facilitate predator learning, variation in these signals often occurs in nature. The strawberry poison frog Dendrobates pumilio is an exceptionally polytypic (populations are phenotypically distinct) aposematic frog exhibiting variation in warning color and brightness. In the Solarte population, males and females both respond differentially to male brightness variation. Here, we demonstrate through spectrophotometry and visual modeling that aposematic brightness variation within this population is likely visible to two putative predators (crabs, snakes) and conspecifics but not to the presumed major predator (birds). This study thus suggests that signal brightness within D. pumilio populations can be shaped by sexual selection, with limited opportunity for natural selection to influence this trait due to predator sensory constraints. Because signal brightness changes can ultimately lead to changes in hue, our findings at the within-population level can provide insights into understanding this polytypism at across-population scales.

Demographic responses to weather fluctuations are context dependent in a long-lived amphibian.

PubMed

Cayuela, Hugo; Arsovski, Dragan; Thirion, Jean-Marc; Bonnaire, Eric; Pichenot, Julian; Boitaud, Sylvain; Miaud, Claude; Joly, Pierre; Besnard, Aurélien

2016-08-01

Weather fluctuations have been demonstrated to affect demographic traits in many species. In long-lived organisms, their impact on adult survival might be buffered by the evolution of traits that reduce variation in interannual adult survival. For example, skipping breeding is an effective behavioral mechanism that may limit yearly variation in adult survival when harsh weather conditions occur; however, this in turn would likely lead to strong variation in recruitment. Yet, only a few studies to date have examined the impact of weather variation on survival, recruitment and breeding probability simultaneously in different populations of the same species. To fill this gap, we studied the impact of spring temperatures and spring rainfall on survival, on reproductive skipping behavior and on recruitment in five populations of a long-lived amphibian, the yellow-bellied toad (Bombina variegata). Based on capture-recapture data, our findings demonstrate that survival depends on interactions between age, population and weather variation. Varying weather conditions in the spring result in strong variation in the survival of immature toads, whereas they have little effect on adult toads. Breeding probability depends on both the individual's previous reproductive status and on the weather conditions during the current breeding season, leading to high interannual variation in recruitment. Crucially, we found that the impact of weather variation on demographic traits is largely context dependent and may thus differ sharply between populations. Our results suggest that studies predicting the impact of climate change on population dynamics should be taken with caution when the relationship between climate and demographic traits is established using only one population or few populations. We therefore highly recommend further research that includes surveys replicated in a substantial number of populations to account for context-dependent variation in demographic processes. © 2016 John Wiley & Sons Ltd.

Pitfalls in Health Communication: Healthcare Policy, Institution, Structure, & Process

PubMed Central

Calderón, José L; Beltrán, Robert A

2004-01-01

The state of health communication for a given population is a function of several tiers of structure and process: government policy, healthcare directives, healthcare structure and process, and the ethnosocial realities of a multicultural society. Common yet specific to these tiers of health communication is the interpersonal and intergroup use of language in all its forms. Language is the most common behavior exhibited by humankind. Its use at all tiers determines quality of healthcare and quality of life for healthcare consumers: patients and their families. Of note, at the consumer end, mounting evidence demonstrates that barriers to health communication contribute to poorer access to care, quality of care, and health outcomes. The lack of comprehensible and usable written and spoken language is a major barrier to health communication targeting primary and secondary disease prevention and is a major contributor to the misuse of healthcare, patient noncompliance, rising healthcare costs. In this paper, we cursorily examine the relationship among government policy, institutional directives, and healthcare structure and process and its influence on the public health, especially vulnerable populations. We conclude that limited health communication in the context of changing healthcare environments and diverse populations is an important underpinning of rising healthcare costs and sustained health disparities. More research is needed to improve communication about health at all tiers and to develop health communication interventions that are usable by all population groups. PMID:15208522

Social communication competence and functional adaptation in a general population of children: preliminary evidence for sex-by-verbal IQ differential risk.

PubMed

Skuse, David H; Mandy, William; Steer, Colin; Miller, Laura L; Goodman, Robert; Lawrence, Kate; Emond, Alan; Golding, Jean

2009-02-01

The proportion of schoolchildren with mild social communicative deficits far exceeds the number diagnosed with an autistic spectrum disorder (ASD). We aimed to ascertain both the population distribution of such deficits and their association with functional adaptation and cognitive ability in middle childhood. The parent-report Social and Communication Disorders Checklist was administered to participants (n = 8,094) in the Avon Longitudinal Study of Parents and Children. We correlated impairment severity with independent clinical diagnoses of ASD, cognitive abilities, and teacher-rated maladaptive behavior. Social and Communication Disorders Checklist scores were continuously distributed in the general population; boys had mean scores 30% higher than girls. Social communicative deficits were associated with functional impairment at school, especially in domains of hyperactivity and conduct disorders. A sex-by-verbal IQ interaction effect occurred: verbal IQ was protective against social communication impairments across the range of abilities in female subjects only. In male subjects, this protective effect did not exist for those with above-average verbal IQ. Social communicative deficits are of prognostic significance, in terms of behavioral adjustment at school, for boys and girls. Their high general population prevalence emphasizes the importance of measuring such traits among clinically referred children who do not meet diagnostic ASD criteria. Above-average verbal IQ seems to confer protection against social communication impairments in female subjects but not in male subjects.

Confidence bounds and hypothesis tests for normal distribution coefficients of variation

Treesearch

Steve Verrill; Richard A. Johnson

2007-01-01

For normally distributed populations, we obtain confidence bounds on a ratio of two coefficients of variation, provide a test for the equality of k coefficients of variation, and provide confidence bounds on a coefficient of variation shared by k populations.

Temporal genetic structure in a poecilogonous polychaete: the interplay of developmental mode and environmental stochasticity

PubMed Central

2014-01-01

Background Temporal variation in the genetic structure of populations can be caused by multiple factors, including natural selection, stochastic environmental variation, migration, or genetic drift. In benthic marine species, the developmental mode of larvae may indicate a possibility for temporal genetic variation: species with dispersive planktonic larvae are expected to be more likely to show temporal genetic variation than species with benthic or brooded non-dispersive larvae, due to differences in larval mortality and dispersal ability. We examined temporal genetic structure in populations of Pygospio elegans, a poecilogonous polychaete with within-species variation in developmental mode. P. elegans produces either planktonic, benthic, or intermediate larvae, varying both among and within populations, providing a within-species test of the generality of a relationship between temporal genetic variation and larval developmental mode. Results In contrast to our expectations, our microsatellite analyses of P. elegans revealed temporal genetic stability in the UK population with planktonic larvae, whereas there was variation indicative of drift in temporal samples of the populations from the Baltic Sea, which have predominantly benthic and intermediate larvae. We also detected temporal variation in relatedness within these populations. A large temporal shift in genetic structure was detected in a population from the Netherlands, having multiple developmental modes. This shift could have been caused by local extiction due to extreme environmental conditions and (re)colonization by planktonic larvae from neighboring populations. Conclusions In our study of P. elegans, temporal genetic variation appears to be due to not only larval developmental mode, but also the stochastic environment of adults. Large temporal genetic shifts may be more likely in marine intertidal habitats (e.g. North Sea and Wadden Sea) which are more prone to environmental stochasticity than the sub-tidal Baltic habitats. Sub-tidal and/or brackish (less saline) habitats may support smaller P. elegans populations and these may be more susceptible to the effects of random genetic drift. Moreover, higher frequencies of asexual reproduction and the benthic larval developmental mode in these populations leads to higher relatedness and contributes to drift. Our results indicate that a general relationship between larval developmental mode and temporal genetic variation may not exist. PMID:24447386

Temporal genetic structure in a poecilogonous polychaete: the interplay of developmental mode and environmental stochasticity.

PubMed

Kesäniemi, Jenni E; Mustonen, Marina; Boström, Christoffer; Hansen, Benni W; Knott, K Emily

2014-01-22

Temporal variation in the genetic structure of populations can be caused by multiple factors, including natural selection, stochastic environmental variation, migration, or genetic drift. In benthic marine species, the developmental mode of larvae may indicate a possibility for temporal genetic variation: species with dispersive planktonic larvae are expected to be more likely to show temporal genetic variation than species with benthic or brooded non-dispersive larvae, due to differences in larval mortality and dispersal ability. We examined temporal genetic structure in populations of Pygospio elegans, a poecilogonous polychaete with within-species variation in developmental mode. P. elegans produces either planktonic, benthic, or intermediate larvae, varying both among and within populations, providing a within-species test of the generality of a relationship between temporal genetic variation and larval developmental mode. In contrast to our expectations, our microsatellite analyses of P. elegans revealed temporal genetic stability in the UK population with planktonic larvae, whereas there was variation indicative of drift in temporal samples of the populations from the Baltic Sea, which have predominantly benthic and intermediate larvae. We also detected temporal variation in relatedness within these populations. A large temporal shift in genetic structure was detected in a population from the Netherlands, having multiple developmental modes. This shift could have been caused by local extiction due to extreme environmental conditions and (re)colonization by planktonic larvae from neighboring populations. In our study of P. elegans, temporal genetic variation appears to be due to not only larval developmental mode, but also the stochastic environment of adults. Large temporal genetic shifts may be more likely in marine intertidal habitats (e.g. North Sea and Wadden Sea) which are more prone to environmental stochasticity than the sub-tidal Baltic habitats. Sub-tidal and/or brackish (less saline) habitats may support smaller P. elegans populations and these may be more susceptible to the effects of random genetic drift. Moreover, higher frequencies of asexual reproduction and the benthic larval developmental mode in these populations leads to higher relatedness and contributes to drift. Our results indicate that a general relationship between larval developmental mode and temporal genetic variation may not exist.

Accommodating environmental variation in population models: metaphysiological biomass loss accounting.

PubMed

Owen-Smith, Norman

2011-07-01

1. There is a pressing need for population models that can reliably predict responses to changing environmental conditions and diagnose the causes of variation in abundance in space as well as through time. In this 'how to' article, it is outlined how standard population models can be modified to accommodate environmental variation in a heuristically conducive way. This approach is based on metaphysiological modelling concepts linking populations within food web contexts and underlying behaviour governing resource selection. Using population biomass as the currency, population changes can be considered at fine temporal scales taking into account seasonal variation. Density feedbacks are generated through the seasonal depression of resources even in the absence of interference competition. 2. Examples described include (i) metaphysiological modifications of Lotka-Volterra equations for coupled consumer-resource dynamics, accommodating seasonal variation in resource quality as well as availability, resource-dependent mortality and additive predation, (ii) spatial variation in habitat suitability evident from the population abundance attained, taking into account resource heterogeneity and consumer choice using empirical data, (iii) accommodating population structure through the variable sensitivity of life-history stages to resource deficiencies, affecting susceptibility to oscillatory dynamics and (iv) expansion of density-dependent equations to accommodate various biomass losses reducing population growth rate below its potential, including reductions in reproductive outputs. Supporting computational code and parameter values are provided. 3. The essential features of metaphysiological population models include (i) the biomass currency enabling within-year dynamics to be represented appropriately, (ii) distinguishing various processes reducing population growth below its potential, (iii) structural consistency in the representation of interacting populations and (iv) capacity to accommodate environmental variation in space as well as through time. Biomass dynamics provide a common currency linking behavioural, population and food web ecology. 4. Metaphysiological biomass loss accounting provides a conceptual framework more conducive for projecting and interpreting the population consequences of climatic shifts and human transformations of habitats than standard modelling approaches. © 2011 The Author. Journal of Animal Ecology © 2011 British Ecological Society.

Analysis of human immunodeficiency virus type 1 Vif gene sequences among men who have sex with men in Heilongjiang province of China.

PubMed

Shao, Bing; Li, Hang; Liu, Sheng-Yuan; Li, Wen-Jing; Huang, Chao-Qun; Lin, Yuan-Long; Wang, Fu-Xiang; Wang, Bin-You

2013-05-01

To identify the current prevalent subtypes and to study the genetic variation of HIV-1 strains in men who have sex with men (MSM) residing in Heilongjiang province, China. We analyzed the characteristics of the nucleotide sequences and the corresponding deduced protein of Vif of HIV-1 strains isolated from 17 drug-naive HIV-1-seropositive MSM. Subtypes B (7.65%) and B' (Thailand B) (11.76%), CRF07_BC (47.06%), and CRF01_AE (23.53%) were identified. Phylogenetic analysis showed that there was a close relationship between our strains and those from the same MSM population in Hebei province, which is geographically close to Heilongjiang. Most of the documented Vif functional motifs are well conserved in the majority of our analyzed sequences. Taken together, our results suggest that there might be multiple introductions of HIV in Heilongjiang MSM and frequent sexual communications with other geographically nearby MSM populations.

The impact of development and population policies on fertility in India.

PubMed

Jain, A K

1985-01-01

This article examines the impact of development and population policies on fertility decline and regional variations in India during the 1970s. Indicators of development at the household level include female literacy and education, infant mortality, and poverty; at the village level they include availability of such social services as schools, medical facilities, and transportation and communication facilities. Multiple regression analysis of data aggregated at the state level demonstrates that conditions conducive to fertility decline include high adult female literacy and low infant mortality as indicators of social development, and high contraceptive use and, to a lesser extent, high female age at marriage as proximate determinants of fertility. There are reasons to believe that India's national family planning program contributed to the decline in fertility observed since the 1960s. The pace of fertility decline in the future will depend upon the pace of infant mortality decline, enhancement in female education, and improvements in family planning programs.

Vascular Variations Associated with Intracranial Aneurysms.

PubMed

Orakdogen, Metin; Emon, Selin Tural; Somay, Hakan; Engin, Taner; Is, Merih; Hakan, Tayfun

2017-01-01

To investigate the vascular variations in patients with intracranial aneurysm in circle of Willis. We used the data on 128 consecutive intracranial aneurysm cases. Cerebral angiography images were analyzed retrospectively. Arteries were grouped as anterior cerebral arterial system (ACS), posterior cerebral arterial system (PCS) and middle cerebral arterial system (MCS) for grouping vascular variations. Lateralization, being single/multiple, gender; and also any connection with accompanying aneurysms" number, localization, dimension, whether bleeding/incidental aneurysm has been inspected. Variations were demonstrated in 57.8% of the cases. The most common variation was A1 variation (34.4%). The rate of variations was 36.7%, 24.2% and 10.2% respectively in ACS, PCS and MCS. MCS variations were significantly higher in males. Anterior communicating artery (ACoA) aneurysm observance rates were significantly higher and posterior communicating artery (PCoA) aneurysm and middle cerebral artery (MCA) aneurysm observance rates were significantly lower when compared to "no ACS variation detected" cases. In "PCS variation detected" cases, PCoA aneurysm observance rates and coexistence of multiple variations were significantly higher. The rate of vascular variations in patients with aneurysms was 57.8%. Arterial hypoplasia and aplasia were the most common variations. ACS was the most common region that variations were located in; they were mostly detected on the right side. Coexistence of ACoA aneurysm was higher than PCoA and MCA aneurysms. In the PCS variations group, PCoA aneurysms were the most common aneurysms that accompanying the variation and multiple variations were more common than in the other two groups. The variations in MCS were most common in males.

Topical Review: Integrating Findings on Direct Observation of Family Communication in Studies Comparing Pediatric Chronic Illness and Typically Developing Samples.

PubMed

Murphy, Lexa K; Murray, Caitlin B; Compas, Bruce E

2017-01-01

To review research on observed family communication in families with children with chronic illnesses compared with families with healthy, typically developing children, and to integrate findings utilizing a unifying family communication framework. Topical review of studies that have directly observed family communication in pediatric populations and included a typically developing comparison group. Initial findings from 14 studies with diverse approaches to quantifying observed family communication suggest that families with children with chronic illnesses may demonstrate lower levels of warm and structured communication and higher levels of hostile/intrusive and withdrawn communication compared with families with healthy, typically developing children. An integrative framework of family communication may be used in future studies that examine the occurrence, correlates, and mechanisms of family communication in pediatric populations.

Phenotypic divergence despite low genetic differentiation in house sparrow populations.

PubMed

Ben Cohen, Shachar; Dor, Roi

2018-01-10

Studying patterns of phenotypic variation among populations can shed light on the drivers of evolutionary processes. The house sparrow (Passer domesticus) is one of the world's most ubiquitous bird species, as well as a successful invader. We investigated phenotypic variation in house sparrow populations across a climatic gradient and in relation to a possible scenario of an invasion. We measured variation in morphological, coloration, and behavioral traits (exploratory behavior and neophobia) and compared it to the neutral genetic variation. We found that sparrows were larger and darker in northern latitudes, in accordance with Bergmann's and Gloger's biogeographic rules. Morphology and behavior mostly differed between the southernmost populations and the other regions, supporting the possibility of an invasion. Genetic differentiation was low and diversity levels were similar across populations, indicating high gene flow. Nevertheless, the southernmost and northern populations differed genetically to some extent. Furthermore, genetic differentiation (F ST ) was lower in comparison to phenotypic variation (P ST ), indicating that the phenotypic variation is shaped by directional selection or by phenotypic plasticity. This study expands our knowledge on evolutionary mechanisms and biological invasions.

China's Population Program at the Grassroots Level: Report on a Field Trip, Summer 1972.

ERIC Educational Resources Information Center

Chen, Pi-chao

The goals of the Caltech Population Program are to increase understanding of the interrelationships between population growth and socioeconomic and cultural patterns throughout the world and to communicate this understanding. This series of occasional papers is one step in the process of communicating research results. The papers deal primarily…

Population size is weakly related to quantitative genetic variation and trait differentiation in a stream fish.

PubMed

Wood, Jacquelyn L A; Tezel, Defne; Joyal, Destin; Fraser, Dylan J

2015-09-01

How population size influences quantitative genetic variation and differentiation among natural, fragmented populations remains unresolved. Small, isolated populations might occupy poor quality habitats and lose genetic variation more rapidly due to genetic drift than large populations. Genetic drift might furthermore overcome selection as population size decreases. Collectively, this might result in directional changes in additive genetic variation (VA ) and trait differentiation (QST ) from small to large population size. Alternatively, small populations might exhibit larger variation in VA and QST if habitat fragmentation increases variability in habitat types. We explored these alternatives by investigating VA and QST using nine fragmented populations of brook trout varying 50-fold in census size N (179-8416) and 10-fold in effective number of breeders, Nb (18-135). Across 15 traits, no evidence was found for consistent differences in VA and QST with population size and almost no evidence for increased variability of VA or QST estimates at small population size. This suggests that (i) small populations of some species may retain adaptive potential according to commonly adopted quantitative genetic measures and (ii) populations of varying sizes experience a variety of environmental conditions in nature, however extremely large studies are likely required before any firm conclusions can be made. © 2015 The Author(s). Evolution © 2015 The Society for the Study of Evolution.

Population genetic analysis and bioclimatic modeling in Agave striata in the Chihuahuan Desert indicate higher genetic variation and lower differentiation in drier and more variable environments.

PubMed

Trejo, Laura; Alvarado-Cárdenas, Leonardo O; Scheinvar, Enrique; Eguiarte, Luis E

2016-06-01

Is there an association between bioclimatic variables and genetic variation within species? This question can be approached by a detailed analysis of population genetics parameters along environmental gradients in recently originated species (so genetic drift does not further obscure the patterns). The genus Agave, with more than 200 recent species encompassing a diversity of morphologies and distributional patterns, is an adequate system for such analyses. We studied Agave striata, a widely distributed species from the Chihuahuan Desert, with a distinctive iteroparous reproductive ecology and two recognized subspecies with clear morphological differences. We used population genetic analyses along with bioclimatic studies to understand the effect of environment on the genetic variation and differentiation of this species. We analyzed six populations of the subspecies A. striata subsp. striata, with a southern distribution, and six populations of A. striata subsp. falcata, with a northern distribution, using 48 ISSR loci and a total of 541 individuals (averaging 45 individuals per population). We assessed correlations between population genetics parameters (the levels of genetic variation and differentiation) and the bioclimatic variables of each population. We modeled each subspecies distribution and used linear correlations and multifactorial analysis of variance. Genetic variation (measured as expected heterozygosity) increased at higher latitudes. Higher levels of genetic variation in populations were associated with a higher variation in environmental temperature and lower precipitation. Stronger population differentiation was associated with wetter and more variable precipitation in the southern distribution of the species. The two subspecies have genetic differences, which coincide with their climatic differences and potential distributions. Differences in genetic variation among populations and the genetic differentiation between A. striata subsp. striata and A. striata subsp. falcata is correlated with differences in environmental climatic variables along their distribution. We found two distinct gene pools that suggest active differentiation and perhaps incipient speciation. The detected association between genetic variation and environment variables indicates that climatic variables are playing an important role in the differentiation of A. striata. © 2016 Botanical Society of America.

Sequence polymorphism data of the hypervariable regions of mitochondrial DNA in the Yadav population of Haryana.

PubMed

Verma, Kapil; Sharma, Sapna; Sharma, Arun; Dalal, Jyoti; Bhardwaj, Tapeshwar

2018-06-01

Genetic variations among humans occur both within and among populations and range from single nucleotide changes to multiple-nucleotide variants. These multiple-nucleotide variants are useful for studying the relationships among individuals or various population groups. The study of human genetic variations can help scientists understand how different population groups are biologically related to one another. Sequence analysis of hypervariable regions of human mitochondrial DNA (mtDNA) has been successfully used for the genetic characterization of different population groups for forensic purposes. It is well established that different ethnic or population groups differ significantly in their mtDNA distributions. In the last decade, very little research has been conducted on mtDNA variations in the Indian population, although such data would be useful for elucidating the history of human population expansion across the world. Moreover, forensic studies on mtDNA variations in the Indian subcontinent are also scarce, particularly in the northern part of India. In this report, variations in the hypervariable regions of mtDNA were analyzed in the Yadav population of Haryana. Different molecular diversity indices were computed. Further, the obtained haplotypes were classified into different haplogroups and the phylogenetic relationship between different haplogroups was inferred.

Genetic variation in natural honeybee populations, Apis mellifera capensis

NASA Astrophysics Data System (ADS)

Hepburn, Randall; Neumann, Peter; Radloff, Sarah E.

2004-09-01

Genetic variation in honeybee, Apis mellifera, populations can be considerably influenced by breeding and commercial introductions, especially in areas with abundant beekeeping. However, in southern Africa apiculture is based on the capture of wild swarms, and queen rearing is virtually absent. Moreover, the introduction of European subspecies constantly failed in the Cape region. We therefore hypothesize a low human impact on genetic variation in populations of Cape honeybees, Apis mellifera capensis. A novel solution to studying genetic variation in honeybee populations based on thelytokous worker reproduction is applied to test this hypothesis. Environmental effects on metrical morphological characters of the phenotype are separated to obtain a genetic residual component. The genetic residuals are then re-calculated as coefficients of genetic variation. Characters measured included hair length on the abdomen, width and length of wax plate, and three wing angles. The data show for the first time that genetic variation in Cape honeybee populations is independent of beekeeping density and probably reflects naturally occurring processes such as gene flow due to topographic and climatic variation on a microscale.

Directional selection effects on patterns of phenotypic (co)variation in wild populations.

PubMed

Assis, A P A; Patton, J L; Hubbe, A; Marroig, G

2016-11-30

Phenotypic (co)variation is a prerequisite for evolutionary change, and understanding how (co)variation evolves is of crucial importance to the biological sciences. Theoretical models predict that under directional selection, phenotypic (co)variation should evolve in step with the underlying adaptive landscape, increasing the degree of correlation among co-selected traits as well as the amount of genetic variance in the direction of selection. Whether either of these outcomes occurs in natural populations is an open question and thus an important gap in evolutionary theory. Here, we documented changes in the phenotypic (co)variation structure in two separate natural populations in each of two chipmunk species (Tamias alpinus and T. speciosus) undergoing directional selection. In populations where selection was strongest (those of T. alpinus), we observed changes, at least for one population, in phenotypic (co)variation that matched theoretical expectations, namely an increase of both phenotypic integration and (co)variance in the direction of selection and a re-alignment of the major axis of variation with the selection gradient. © 2016 The Author(s).

Genetic differentiation among populations of marine algae

NASA Astrophysics Data System (ADS)

Innes, D. J.

1984-09-01

Most of the information for genetic differentiation among populations of marine algae is from studies on ecotypic variation. Physiological ecotypes have been described for individuals showing different responses to temperature and salinity conditions. Morphological ecotypes have also been found associated with areas differing in wave exposure or different intertidal positions. Little is known on how genetic variation is organized within and between populations of marine algae. The occurrence of ecotypic variation in some species is evidence for genetic differentiation among populations resulting from selection by the local environment. The rate of dispersal and subsequent gene flow will also affect the level of differentiation among populations. In species with low dispersal, differentiation can arise through chance founder events or random genetic drift. The few studies available have shown that species of algae exhibit a range of dispersal capabilities. This information can be useful for predicting the potential level of genetic differentiation among populations of these species. Crossing experiments with several species of algae have shown that populations separated by a considerable distance can be interfertile. In some cases individuals from these populations have been found to be morphologically distinct. Crosses have been used to study the genetic basis of this variation and are evidence for genetic differentiation among the populations sampled. Genetic variation of enzyme proteins detected by electrophoresis provides an additional method for measuring genetic variation within and between populations of marine algae. Electrophoretic methods have previously been used to study systematic problems in algae. However, there have been few attempts to use electrophoretic variation to study the genetic structure of populations of marine algae. This approach is outlined and includes some of the potential problems associated with interpreting electrophoretic data. Studies of electrophoretic variation in natural populations of Enteromorpha linza from Long island Sound are used as an example. This species was found to reproduce only asexually. Despite a dispersing spore stage, genetic differentiation was found on a microgeographic scale and was correlated with differences in the local environment of some of the populations. Similar studies on other species, and especially sexually reproducing species, will add to a growing understanding of the evolutionary genetics of marine algae.

Intra-population level variation in thresholds for physical dormancy-breaking temperature

PubMed Central

Liyanage, Ganesha S.; Ooi, Mark K. J.

2015-01-01

Background and Aims Intra-population variation in seed dormancy is an advantage for population persistence in unpredictable environments. The important role played by physically dormant species in these habitats makes understanding the level of variation in their dormancy a key ecological question. Heat produced in the soil is the major dormancy-breaking stimulus and, in fire prone ecosystems, soil temperatures generated by fire may vary spatially and over time. While many studies have investigated variation in initial dormancy, a measure that is of little value in fire-prone ecosystems, where initial dormancy levels are uniformly high, intra-population variation in dormancy-breaking temperature thresholds has never been quantified. This study predicted that species would display variation in dormancy-breaking temperature thresholds within populations, and investigated whether this variation occurred between individual plants from the same maternal environment. Methods The intra-population variation in dormancy-breaking thresholds of five common physically dormant shrub species (family Fabaceae) from fire-prone vegetation in south-eastern Australia was assessed using heat treatments and germination trials. Replicate batches of seeds from each of four maternal plants of Dillwynia floribunda, Viminaria juncea, Bossiaea heterophylla, Aotus ericoides and Acacia linifolia were treated at 40, 60, 80, 100 and 120 °C. Key Results Dormancy-breaking response to heat treatments varied significantly among individual plants for all species, with some individuals able to germinate after heating at low temperatures and others restricting germination to temperatures that only occur as a result of high-severity fires. Germination rate (T50) varied among individuals of three species. Conclusions Variation detected among individuals that were in close proximity to each other indicates that strong differences in dormancy-breaking temperature thresholds occur throughout the broader population. Differences found at the individual plant level could contribute to subsequent variation within the seed bank, providing a bet-hedging strategy, and represent a mechanism for increasing the probability of population persistence in the face of fire regime variability. PMID:25997432

Evidence for acoustic communication among bottom foraging humpback whales

PubMed Central

Parks, Susan E.; Cusano, Dana A.; Stimpert, Alison K.; Weinrich, Mason T.; Friedlaender, Ari S.; Wiley, David N.

2014-01-01

Humpback whales (Megaptera novaeangliae), a mysticete with a cosmopolitan distribution, demonstrate marked behavioural plasticity. Recent studies show evidence of social learning in the transmission of specific population level traits ranging from complex singing to stereotyped prey capturing behaviour. Humpback whales have been observed to employ group foraging techniques, however details on how individuals coordinate behaviour in these groups is challenging to obtain. This study investigates the role of a novel broadband patterned pulsed sound produced by humpback whales engaged in bottom-feeding behaviours, referred to here as a ‘paired burst' sound. Data collected from 56 archival acoustic tag deployments were investigated to determine the functional significance of these signals. Paired burst sound production was associated exclusively with bottom feeding under low-light conditions, predominantly with evidence of associated conspecifics nearby suggesting that the sound likely serves either as a communicative signal to conspecifics, a signal to affect prey behaviour, or possibly both. This study provides additional evidence for individual variation and phenotypic plasticity of foraging behaviours in humpback whales and provides important evidence for the use of acoustic signals among foraging individuals in this species. PMID:25512188

Evidence for acoustic communication among bottom foraging humpback whales.

PubMed

Parks, Susan E; Cusano, Dana A; Stimpert, Alison K; Weinrich, Mason T; Friedlaender, Ari S; Wiley, David N

2014-12-16

Humpback whales (Megaptera novaeangliae), a mysticete with a cosmopolitan distribution, demonstrate marked behavioural plasticity. Recent studies show evidence of social learning in the transmission of specific population level traits ranging from complex singing to stereotyped prey capturing behaviour. Humpback whales have been observed to employ group foraging techniques, however details on how individuals coordinate behaviour in these groups is challenging to obtain. This study investigates the role of a novel broadband patterned pulsed sound produced by humpback whales engaged in bottom-feeding behaviours, referred to here as a 'paired burst' sound. Data collected from 56 archival acoustic tag deployments were investigated to determine the functional significance of these signals. Paired burst sound production was associated exclusively with bottom feeding under low-light conditions, predominantly with evidence of associated conspecifics nearby suggesting that the sound likely serves either as a communicative signal to conspecifics, a signal to affect prey behaviour, or possibly both. This study provides additional evidence for individual variation and phenotypic plasticity of foraging behaviours in humpback whales and provides important evidence for the use of acoustic signals among foraging individuals in this species.

Group social skills interventions for adults with high-functioning autism spectrum disorders: A systematic review.

PubMed

Spain, Debbie; Blainey, Sarah H

2015-10-01

Autism spectrum disorders are characterised by impairments in communication and social interaction. Social skills interventions have been found to ameliorate socio-communication deficits in children and adolescents with autism spectrum disorders. Little is known about the effectiveness of social skills interventions for adults with high-functioning autism spectrum disorders (hf-ASD) - a clinical population who can present with more subtle core deficits, but comparable levels of impairment and secondary difficulties. A systematic review was undertaken to investigate the effectiveness of social skills interventions for adults with high-functioning autism spectrum disorders. Five studies met the pre-specified review inclusion criteria: two quasi-experimental comparative trials and three single-arm interventions. There was a degree of variation in the structure, duration and content of the social skills interventions delivered, as well as several methodological limitations associated with included studies. Nevertheless, narrative analysis tentatively indicates that group social skills interventions may be effective for enhancing social knowledge and understanding, improving social functioning, reducing loneliness and potentially alleviating co-morbid psychiatric symptoms. © The Author(s) 2015.

Loss of Mhc and Neutral Variation in Peary Caribou: Genetic Drift Is Not Mitigated by Balancing Selection or Exacerbated by Mhc Allele Distributions

PubMed Central

Taylor, Sabrina S.; Jenkins, Deborah A.; Arcese, Peter

2012-01-01

Theory and empirical results suggest that the rate of loss of variation at Mhc and neutral microsatellite loci may differ because selection influences Mhc genes, and because a high proportion of rare alleles at Mhc loci may result in high rates of loss via drift. Most published studies compare Mhc and microsatellite variation in various contemporary populations to infer the effects of population size on genetic variation, even though different populations are likely to have different demographic histories that may also affect contemporary genetic variation. We directly compared loss of variation at Mhc and microsatellite loci in Peary caribou by comparing historical and contemporary samples. We observed that similar proportions of genetic variation were lost over time at each type of marker despite strong evidence for selection at Mhc genes. These results suggest that microsatellites can be used to estimate genome-wide levels of variation, but also that adaptive potential is likely to be lost following population bottlenecks. However, gene conversion and recombination at Mhc loci may act to increase variation following bottlenecks. PMID:22655029

Ecological and evolutionary influences on body size and shape in the Galápagos marine iguana (Amblyrhynchus cristatus).

PubMed

Chiari, Ylenia; Glaberman, Scott; Tarroso, Pedro; Caccone, Adalgisa; Claude, Julien

2016-07-01

Oceanic islands are often inhabited by endemic species that have undergone substantial morphological evolutionary change due to processes of multiple colonizations from various source populations, dispersal, and local adaptation. Galápagos marine iguanas are an example of an island endemic exhibiting high morphological diversity, including substantial body size variation among populations and sexes, but the causes and magnitude of this variation are not well understood. We obtained morphological measurements from marine iguanas throughout their distribution range. These data were combined with genetic and local environmental data from each population to investigate the effects of evolutionary history and environmental conditions on body size and shape variation and sexual dimorphism. Our results indicate that body size and shape are highly variable among populations. Sea surface temperature and island perimeter, but not evolutionary history as depicted by phylogeographic patterns in this species, explain variation in body size among populations. Conversely, evolutionary history, but not environmental parameters or island size, was found to influence variation in body shape among populations. Finally, in all populations except one, we found strong sexual dimorphism in body size and shape in which males are larger, with higher heads than females, while females have longer heads than males. Differences among populations suggest that plasticity and/or genetic adaptation may shape body size and shape variation in marine iguanas. This study will help target future investigations to address the contribution of plasticity versus genetic adaptation on size and shape variation in marine iguanas.

Variations in Figurative Language Use as a Function of Mode of Communication

ERIC Educational Resources Information Center

Boerger, Michael A.

2005-01-01

Various studies have demonstrated that the mode by which people communicate affects the content of their messages. The present study examines the ways in which one aspect of language use, namely figurative language, differs as a function of mode of communication. Subjects worked together in pairs to build a small household appliance, with an…

Meiotic sex ratio variation in natural populations of Ceratodon purpureus (Ditrichaceae).

PubMed

Norrell, Tatum E; Jones, Kelly S; Payton, Adam C; McDaniel, Stuart F

2014-09-01

• Sex ratio variation is a common but often unexplained phenomenon in species across the tree of life. Here we evaluate the hypothesis that meiotic sex ratio variation can contribute to the biased sex ratios found in natural populations of the moss Ceratodon purpureus.• We obtained sporophytes from several populations of C. purpureus from eastern North America. From each sporophyte, we estimated the mean spore viability by germinating replicate samples on agar plates. We estimated the meiotic sex ratio of each sporophyte by inferring the sex of a random sample of germinated spores (mean = 77) using a PCR-RFLP test. We tested for among-sporophyte variation in viability using an ANOVA and for deviations from 1:1 sex ratio using a χ(2)-test and evaluated the relationship between these quantities using a linear regression.• We found among-sporophyte variation in spore viability and meiotic sex ratio, suggesting that genetic variants that contribute to variation in both of these traits segregate within populations of this species. However, we found no relationship between these quantities, suggesting that factors other than sex ratio distorters contribute to variation in spore viability within populations.• These results demonstrate that sex ratio distortion may partially explain the population sex ratio variation seen in C. purpureus, but more generally that genetic conflict over meiotic segregation may contribute to fitness variation in this species. Overall, this study lays the groundwork for future studies on the genetic basis of meiotic sex ratio variation. © 2014 Botanical Society of America, Inc.

Genetic spectrum of low density lipoprotein receptor gene variations in South Indian population.

PubMed

ArulJothi, K N; Suruthi Abirami, B; Devi, Arikketh

2018-03-01

Low density lipoprotein receptor (LDLR) is a membrane bound receptor maintaining cholesterol homeostasis along with Apolipoprotein B (APOB), Proprotein Convertase Subtilisin/Kexin type 9 (PCSK9) and other genes of lipid metabolism. Any pathogenic variation in these genes alters the function of the receptor and leads to Familial Hypercholesterolemia (FH) and other cardiovascular diseases. This study was aimed at screening the LDLR, APOB and PCSK9 genes in Hypercholesterolemic patients to define the genetic spectrum of FH in Indian population. Familial Hypercholesterolemia patients (n=78) of South Indian Tamil population with LDL cholesterol and Total cholesterol levels above 4.9mmol/l and 7.5mmol/l with family history of Myocardial infarction were involved. DNA was isolated by organic extraction method from blood samples and LDLR, APOB and PCSK9 gene exons were amplified using primers that cover exon-intron boundaries. The amplicons were screened using High Resolution Melt (HRM) Analysis and the screened samples were sequenced after purification. This study reports 20 variations in South Indian population for the first time. In this set of variations 9 are novel variations which are reported for the first time, 11 were reported in other studies also. The in silico analysis for all the variations detected in this study were done to predict the probabilistic effect in pathogenicity of FH. This study adds 9 novel variations and 11 recurrent variations to the spectrum of LDLR gene mutations in Indian population. All these variations are reported for the first time in Indian population. This spectrum of variations was different from the variations of previous Indian reports. Copyright © 2017 Elsevier B.V. All rights reserved.

AIDS communications through social networks: catalyst for behaviour changes in Uganda.

PubMed

Low-Beer, Daniel; Stoneburner, Rand L

2004-05-01

To investigate distinctive communications through social networks which may be associated with population behaviour changes and HIV prevalence declines in Uganda compared to other countries. We undertook a comparative analysis of demographic and HIV behavioural data collected in Demographic and Health Surveys (DHS III) in Uganda, Kenya, Tanzania, Malawi, Zambia and Zimbabwe as well as Knowledge, Attitudes and Behaviours (KABP) surveys in Uganda in 1989 and 1995. AIDS behaviours, social communications and channels for communication about AIDS and people with AIDS were analysed by age, sex and country. Modelling was developed to investigate at what stage of the epidemic a majority of people will know someone with AIDS, given differing communication patterns through social networks. Finally AIDS reporting and Voluntary Counselling and Testing (VCT) trends were analysed to assess if the impact of social communications worked through clinical services and interventions or more directly at the population level in community contexts. Uganda showed unique patterns of communications through social networks including a shift from mass and institutional to personal channels for communicating about AIDS, 1989-1995. This was associated with higher levels of knowing someone with AIDS through social networks and, in turn, positive risk ratios for behaviour change including reducing casual sex and condom use. Youth had distinctively high levels of knowing someone with AIDS in Uganda, suggesting widespread community communication across age groups. Patterns of disclosure, AIDS diagnosis and reporting were influential on social communications about AIDS. Over 90%, 45% or under 20% of people know someone with AIDS at peak HIV incidence and high AIDS mortality, depending on whether communications through social networks are extensive or restricted. There are distinctive patterns for communicating through social networks about AIDS and people with AIDS in Uganda. They appear to work directly at population level rather than in response to clinical interventions and testing and may be important in the uptake of the latter services. This communication response provides an important basis for HIV prevention if it is to be scaled to the population level. Vertical prevention (and even treatment) interventions need to engage more closely with local, horizontal communication and behavioural responses to AIDS. Communication programmes have to take root at the level of social networks working though local networks of meetings, chiefs, churches and health personnel as well as the media. Mobilising basic social communications may be a necessary resource (as much as services and finance) to scale HIV prevention and treatment to the population level.

Species conservation and natural variation among populations [Chapter 5

Treesearch

Leonard F. Ruggiero; Michael K. Schwartz; Keith B. Aubry; Charles J. Krebs; Amanda Stanley; Steven W. Buskirk

2000-01-01

In conservation planning, the importance of natural variation is often given inadequate consideration. However, ignoring the implications of variation within species may result in conservation strategies that jeopardize, rather than conserve, target species (see Grieg 1979; Turcek 1951; Storfer 1999). Natural variation in the traits of individuals and populations is...

Maintenance of genetic diversity through plant-herbivore interactions

PubMed Central

Gloss, Andrew D.; Dittrich, Anna C. Nelson; Goldman-Huertas, Benjamin; Whiteman, Noah K.

2013-01-01

Identifying the factors governing the maintenance of genetic variation is a central challenge in evolutionary biology. New genomic data, methods and conceptual advances provide increasing evidence that balancing selection, mediated by antagonistic species interactions, maintains functionally-important genetic variation within species and natural populations. Because diverse interactions between plants and herbivorous insects dominate terrestrial communities, they provide excellent systems to address this hypothesis. Population genomic studies of Arabidopsis thaliana and its relatives suggest spatial variation in herbivory maintains adaptive genetic variation controlling defense phenotypes, both within and among populations. Conversely, inter-species variation in plant defenses promotes adaptive genetic variation in herbivores. Emerging genomic model herbivores of Arabidopsis could illuminate how genetic variation in herbivores and plants interact simultaneously. PMID:23834766

Stochastic population dynamics in populations of western terrestrial garter snakes with divergent life histories

USGS Publications Warehouse

Miller, David A.; Clark, W.R.; Arnold, S.J.; Bronikowski, A.M.

2011-01-01

Comparative evaluations of population dynamics in species with temporal and spatial variation in life-history traits are rare because they require long-term demographic time series from multiple populations. We present such an analysis using demographic data collected during the interval 1978-1996 for six populations of western terrestrial garter snakes (Thamnophis elegans) from two evolutionarily divergent ecotypes. Three replicate populations from a slow-living ecotype, found in mountain meadows of northeastern California, were characterized by individuals that develop slowly, mature late, reproduce infrequently with small reproductive effort, and live longer than individuals of three populations of a fast-living ecotype found at lakeshore locales. We constructed matrix population models for each of the populations based on 8-13 years of data per population and analyzed both deterministic dynamics based on mean annual vital rates and stochastic dynamics incorporating annual variation in vital rates. (1) Contributions of highly variable vital rates to fitness (??s) were buffered against the negative effects of stochastic variation, and this relationship was consistent with differences between the meadow (M-slow) and lakeshore (L-fast) ecotypes. (2) Annual variation in the proportion of gravid females had the greatest negative effect among all vital rates on ?? s. The magnitude of variation in the proportion of gravid females and its effect on ??s was greater in M-slow than L-fast populations. (3) Variation in the proportion of gravid females, in turn, depended on annual variation in prey availability, and its effect on ??s was 4- 23 times greater in M-slow than L-fast populations. In addition to differences in stochastic dynamics between ecotypes, we also found higher mean mortality rates across all age classes in the L-fast populations. Our results suggest that both deterministic and stochastic selective forces have affected the evolution of divergent life-history traits in the two ecotypes, which, in turn, affect population dynamics. M-slow populations have evolved life-history traits that buffer fitness against direct effects of variation in reproduction and that spread lifetime reproduction across a greater number of reproductive bouts. These results highlight the importance of long-term demographic and environmental monitoring and of incorporating temporal dynamics into empirical studies of life-history evolution. ?? 2011 by the Ecological Society of America.

Stochastic population dynamics in populations of western terrestrial garter snakes with divergent life histories.

PubMed

Miller, David A; Clark, William R; Arnold, Stevan J; Bronikowski, Anne M

2011-08-01

Comparative evaluations of population dynamics in species with temporal and spatial variation in life-history traits are rare because they require long-term demographic time series from multiple populations. We present such an analysis using demographic data collected during the interval 1978-1996 for six populations of western terrestrial garter snakes (Thamnophis elegans) from two evolutionarily divergent ecotypes. Three replicate populations from a slow-living ecotype, found in mountain meadows of northeastern California, were characterized by individuals that develop slowly, mature late, reproduce infrequently with small reproductive effort, and live longer than individuals of three populations of a fast-living ecotype found at lakeshore locales. We constructed matrix population models for each of the populations based on 8-13 years of data per population and analyzed both deterministic dynamics based on mean annual vital rates and stochastic dynamics incorporating annual variation in vital rates. (1) Contributions of highly variable vital rates to fitness (lambda(s)) were buffered against the negative effects of stochastic variation, and this relationship was consistent with differences between the meadow (M-slow) and lakeshore (L-fast) ecotypes. (2) Annual variation in the proportion of gravid females had the greatest negative effect among all vital rates on lambda(s). The magnitude of variation in the proportion of gravid females and its effect on lambda(s) was greater in M-slow than L-fast populations. (3) Variation in the proportion of gravid females, in turn, depended on annual variation in prey availability, and its effect on lambda(s) was 4 23 times greater in M-slow than L-fast populations. In addition to differences in stochastic dynamics between ecotypes, we also found higher mean mortality rates across all age classes in the L-fast populations. Our results suggest that both deterministic and stochastic selective forces have affected the evolution of divergent life-history traits in the two ecotypes, which, in turn, affect population dynamics. M-slow populations have evolved life-history traits that buffer fitness against direct effects of variation in reproduction and that spread lifetime reproduction across a greater number of reproductive bouts. These results highlight the importance of long-term demographic and environmental monitoring and of incorporating temporal dynamics into empirical studies of life-history evolution.

Effects of functionally asexual reproduction on quantitative genetic variation in the evening primroses (Oenothera, Onagraceae).

PubMed

Godfrey, Ryan M; Johnson, Marc T J

2014-11-01

It has long been predicted that a loss of sexual reproduction leads to decreased heritable variation within populations and increased differentiation between populations. Despite an abundance of theory, there are few empirical tests of how sex affects genetic variation in phenotypic traits, especially for plants. Here we test whether repeated losses of two critical components of sex (recombination and segregation) in the evening primroses (Oenothera L., Onagraceae) affect quantitative genetic variation within and between populations. We sampled multiple genetic families from 3-5 populations from each of eight Oenothera species, which represented four independent transitions between sexual reproduction and a functionally asexual genetic system called "permanent translocation heterozygosity." We used quantitative genetics methods to partition genetic variation within and between populations for eight plant traits related to growth, leaf physiology, flowering, and resistance to herbivores. Heritability was, on average, 74% higher in sexual Oenothera populations than in functionally asexual populations, with plant growth rate, specific leaf area, and the percentage of leaf water content showing the strongest differences. By contrast, genetic differentiation among populations was 2.8× higher in functionally asexual vs. sexual Oenothera species. This difference was particularly strong for specific leaf area. Sexual populations tended to exhibit higher genetic correlations among traits, but this difference was weakly supported. These results support the prediction that sexual reproduction maintains higher genetic variation within populations, which may facilitate adaptive evolution. We also found partial support for the prediction that a loss of sex leads to greater population differentiation, which may elevate speciation rates. © 2014 Botanical Society of America, Inc.

[Prevention of skin cancer: considerations on strategic communication].

PubMed

Anders, M P; Baumann, E; Breitbart, E W

2014-03-01

In recent decades the numbers of cases of skin cancer have been increasing worldwide in light skinned populations. In Germany skin cancer is the most common form of cancer. To reduce the burden of skin cancer protection from ultraviolet radiation (primary prevention) and early detection (secondary prevention) of the disease play a decisive role. In this context information to the population about preventive behavior and the support of informed decision-making in skin cancer screening are important aspects in communication. This paper gives an overview about communicational aspects in the promotion of skin cancer prevention. In the development of communicational interventions it is important to identify the relevant target groups. Relevant key opinion leaders have to be included in the information process. Additionally, interventions should be based on a theoretical framework and be designed for the respective target group. Furthermore, different forms of communication and communication tools are provided for the realization of an information intervention. To appraise the intervention elements of summative and formal evaluation are available. The current results provide important findings about different effects of communicational aspects on knowledge and behavior of the population; however, due to the complexity of information interventions a particular effect cannot be explained by a single communicational element.

Identifying tagging SNPs for African specific genetic variation from the African Diaspora Genome

PubMed Central

Johnston, Henry Richard; Hu, Yi-Juan; Gao, Jingjing; O’Connor, Timothy D.; Abecasis, Gonçalo R.; Wojcik, Genevieve L; Gignoux, Christopher R.; Gourraud, Pierre-Antoine; Lizee, Antoine; Hansen, Mark; Genuario, Rob; Bullis, Dave; Lawley, Cindy; Kenny, Eimear E.; Bustamante, Carlos; Beaty, Terri H.; Mathias, Rasika A.; Barnes, Kathleen C.; Qin, Zhaohui S.; Preethi Boorgula, Meher; Campbell, Monica; Chavan, Sameer; Ford, Jean G.; Foster, Cassandra; Gao, Li; Hansel, Nadia N.; Horowitz, Edward; Huang, Lili; Ortiz, Romina; Potee, Joseph; Rafaels, Nicholas; Ruczinski, Ingo; Scott, Alan F.; Taub, Margaret A.; Vergara, Candelaria; Levin, Albert M.; Padhukasahasram, Badri; Williams, L. Keoki; Dunston, Georgia M.; Faruque, Mezbah U.; Gietzen, Kimberly; Deshpande, Aniket; Grus, Wendy E.; Locke, Devin P.; Foreman, Marilyn G.; Avila, Pedro C.; Grammer, Leslie; Kim, Kwang-Youn A.; Kumar, Rajesh; Schleimer, Robert; De La Vega, Francisco M.; Shringarpure, Suyash S.; Musharoff, Shaila; Burchard, Esteban G.; Eng, Celeste; Hernandez, Ryan D.; Pino-Yanes, Maria; Torgerson, Dara G.; Szpiech, Zachary A.; Torres, Raul; Nicolae, Dan L.; Ober, Carole; Olopade, Christopher O; Olopade, Olufunmilayo; Oluwole, Oluwafemi; Arinola, Ganiyu; Song, Wei; Correa, Adolfo; Musani, Solomon; Wilson, James G.; Lange, Leslie A.; Akey, Joshua; Bamshad, Michael; Chong, Jessica; Fu, Wenqing; Nickerson, Deborah; Reiner, Alexander; Hartert, Tina; Ware, Lorraine B.; Bleecker, Eugene; Meyers, Deborah; Ortega, Victor E.; Maul, Pissamai; Maul, Trevor; Watson, Harold; Ilma Araujo, Maria; Riccio Oliveira, Ricardo; Caraballo, Luis; Marrugo, Javier; Martinez, Beatriz; Meza, Catherine; Ayestas, Gerardo; Francisco Herrera-Paz, Edwin; Landaverde-Torres, Pamela; Erazo, Said Omar Leiva; Martinez, Rosella; Mayorga, Alvaro; Mayorga, Luis F.; Mejia-Mejia, Delmy-Aracely; Ramos, Hector; Saenz, Allan; Varela, Gloria; Marina Vasquez, Olga; Ferguson, Trevor; Knight-Madden, Jennifer; Samms-Vaughan, Maureen; Wilks, Rainford J.; Adegnika, Akim; Ateba-Ngoa, Ulysse; Yazdanbakhsh, Maria

2017-01-01

A primary goal of The Consortium on Asthma among African-ancestry Populations in the Americas (CAAPA) is to develop an ‘African Diaspora Power Chip’ (ADPC), a genotyping array consisting of tagging SNPs, useful in comprehensively identifying African specific genetic variation. This array is designed based on the novel variation identified in 642 CAAPA samples of African ancestry with high coverage whole genome sequence data (~30× depth). This novel variation extends the pattern of variation catalogued in the 1000 Genomes and Exome Sequencing Projects to a spectrum of populations representing the wide range of West African genomic diversity. These individuals from CAAPA also comprise a large swath of the African Diaspora population and incorporate historical genetic diversity covering nearly the entire Atlantic coast of the Americas. Here we show the results of designing and producing such a microchip array. This novel array covers African specific variation far better than other commercially available arrays, and will enable better GWAS analyses for researchers with individuals of African descent in their study populations. A recent study cataloging variation in continental African populations suggests this type of African-specific genotyping array is both necessary and valuable for facilitating large-scale GWAS in populations of African ancestry. PMID:28429804

Evolution of Implicit and Explicit Communication in Mobile Robots

NASA Astrophysics Data System (ADS)

de Greeff, Joachim; Nolfi, Stefano

This work investigates the conditions in which a population of embodied agents evolved for the ability to display coordinated/cooperative skills can develop an ability to communicate, whether and to what extent the evolved communication system can complexify during the course of the evolutionary process, and how the characteristics of such communication system varies evolutionarily. The analysis of the obtained results indicates that evolving robots develop a capacity to access/generate information which has a communicative value, an ability to produce different signals encoding useful regularities, and an ability to react appropriately to explicit and implicit signals. The analysis of the obtained results allows us to formulate detailed hypothesis on the evolution of communication for what concern aspects such us: (i) how communication can emerge from a population of initially non-communicating agents, (ii) how communication systems can complexify, (iii) how signals/meanings can originate and how they can be grounded in agents' sensory-motor states.

Shape variation in the least killifish: ecological associations of phenotypic variation and the effects of a common garden.

PubMed

Landy, J Alex; Travis, Joseph

2015-12-01

Studies of the adaptive significance of variation among conspecific populations often focus on a single ecological factor. However, habitats rarely differ in only a single ecological factor, creating a challenge for identifying the relative importance of the various ecological factors that might be maintaining local adaptation. Here we investigate the ecological factors associated with male body shape variation among nine populations of the poeciliid fish, Heterandria formosa, from three distinct habitats and combine those results with a laboratory study of three of those populations to assess the contributions of genetic and environmental influences to shape variation. Field-collected animals varied principally in three ways: the orientation of the gonopodium, the intromittent organ; the degree of body depth and streamlining; and the shape of the tail musculature. Fish collected in the spring season were larger and had a more anteriorly positioned gonopodium than fish collected in autumn. Fish collected from lotic springs were larger and more streamlined than those collected from lentic ponds or tidal marshes. Some of the variation in male shape among populations within habitats was associated with population-level variation in species richness, adult density, vegetative cover, predation risk, and female standard length. Population-level differences among males in body size, position of the gonopodium, and shape of the tail musculature were maintained among males reared in a common environment. In contrast, population variation in the degree of streamlining was eliminated when males were reared in a common environment. These results illustrate the complicated construction of multivariate phenotypic variation and suggest that different agents of selection have acted on different components of shape.

Predicting Response to Reassurances and Uncertainties in Bioterrorism Communications for Urban Populations in New York and California

PubMed Central

Vaughan, Elaine; Tinker, Tim L.; Truman, Benedict I.; Edelson, Paul; Morse, Stephen S.

2015-01-01

Recent national plans for recovery from bioterrorism acts perpetrated in densely populated urban areas acknowledge the formidable technical and social challenges of consequence management. Effective risk and crisis communication is one priority to strengthen the U.S.’s response and resilience. However, several notable risk events since September 11, 2001, have revealed vulnerabilities in risk/crisis communication strategies and infrastructure of agencies responsible for protecting civilian populations. During recovery from a significant biocontamination event, 2 goals are essential: (1) effective communication of changing risk circumstances and uncertainties related to cleanup, restoration, and reoccupancy; and (2) adequate responsiveness to emerging information needs and priorities of diverse populations in high-threat, vulnerable locations. This telephone survey study explored predictors of public reactions to uncertainty communications and reassurances from leaders related to the remediation stage of an urban-based bioterrorism incident. African American and Hispanic adults (N = 320) were randomly sampled from 2 ethnically and socioeconomically diverse geographic areas in New York and California assessed as high threat, high vulnerability for terrorism and other public health emergencies. Results suggest that considerable heterogeneity exists in risk perspectives and information needs within certain sociodemographic groups; that success of risk/crisis communication during recovery is likely to be uneven; that common assumptions about public responsiveness to particular risk communications need further consideration; and that communication effectiveness depends partly on preexisting values and risk perceptions and prior trust in leaders. Needed improvements in communication strategies are possible with recognition of where individuals start as a reference point for reasoning about risk information, and comprehension of how this influences subsequent interpretation of agencies’ actions and communications. PMID:22582813

Predicting response to reassurances and uncertainties in bioterrorism communications for urban populations in New York and California.

PubMed

Vaughan, Elaine; Tinker, Tim L; Truman, Benedict I; Edelson, Paul; Morse, Stephen S

2012-06-01

Recent national plans for recovery from bioterrorism acts perpetrated in densely populated urban areas acknowledge the formidable technical and social challenges of consequence management. Effective risk and crisis communication is one priority to strengthen the U.S.'s response and resilience. However, several notable risk events since September 11, 2001, have revealed vulnerabilities in risk/crisis communication strategies and infrastructure of agencies responsible for protecting civilian populations. During recovery from a significant biocontamination event, 2 goals are essential: (1) effective communication of changing risk circumstances and uncertainties related to cleanup, restoration, and reoccupancy; and (2) adequate responsiveness to emerging information needs and priorities of diverse populations in high-threat, vulnerable locations. This telephone survey study explored predictors of public reactions to uncertainty communications and reassurances from leaders related to the remediation stage of an urban-based bioterrorism incident. African American and Hispanic adults (N=320) were randomly sampled from 2 ethnically and socioeconomically diverse geographic areas in New York and California assessed as high threat, high vulnerability for terrorism and other public health emergencies. Results suggest that considerable heterogeneity exists in risk perspectives and information needs within certain sociodemographic groups; that success of risk/crisis communication during recovery is likely to be uneven; that common assumptions about public responsiveness to particular risk communications need further consideration; and that communication effectiveness depends partly on preexisting values and risk perceptions and prior trust in leaders. Needed improvements in communication strategies are possible with recognition of where individuals start as a reference point for reasoning about risk information, and comprehension of how this influences subsequent interpretation of agencies' actions and communications.

[What do functionally defined populations contribute to the explanation of regional differences in medical care?].

PubMed

Graf von Stillfried, D; Czihal, T

2014-02-01

Geographic variation in health care is increasingly subject to analysis and health policy aiming at the suitable allocation of resources and the reduction of unwarranted variation for the patient populations concerned. As in the case of area-level indicators, in most cases populations are geographically defined. The concept of geographically defined populations, however, may be self-limiting with respect to identifying the potential for improvement. As an alternative, we explored how a functional definition of populations would support defining the scope for reducing unwarranted geographical variations. Given that patients in Germany have virtually no limits in accessing physicians of their choice, we adapted a method that has been developed in the United States to create virtual networks of physicians based on commonly treated patients. Using the physician claims data under statutory insurance, which covers 90% of the population, we defined 43,006 populations-and networks-in 2010. We found that there is considerable variation between the population in terms of their risk structure and the share of the primary care practice in the total services provided. Moreover, there are marked differences in the size and structure of networks between cities, densely populated regions, and rural regions. We analyzed the variation for two area-level indicators: the proportion of diabetics with at least one HbA1c test per year for diabetics, and the proportion of patients with low back pain undergoing computed tomography and/or magnetic resonance imaging. Variation at the level of functionally defined populations proved to be larger than for geographically defined populations. The pattern of distribution gives evidence on the degree to which consensus targets could be reached and which networks need to be addressed in order to reduce unwarranted regional variation. The concept of functionally defined populations needs to be further developed before implementation.

Comparative biology of the crab Goniopsis cruentata: geographic variation of body size, sexual maturity, and allometric growth

NASA Astrophysics Data System (ADS)

de Lira, José Jonathas Pereira Rodrigues; Calado, Tereza Cristina dos Santos; Rezende, Carla Ferreira; Silva, José Roberto Feitosa

2015-12-01

Geographic variation of phenotypic traits is common across species and is often associated with variation in environmental conditions. Here, we found larger bodies and larger size at maturity in a northward, lower latitude population of the crab Goniopsis cruentata, which inhabits a hotter, drier environment in comparison with a southward, higher latitude population. Furthermore, the juvenile male gonopods grow more relative to body size in the population characterized by maturation at a smaller size. In contrast, the female abdomen widens at a higher rate among the late maturing population. These results provide further evidence that local environmental conditions play a role in phenotypic variation between populations inhabiting different latitudes. Moreover, they also show that variation in size at maturity and body size can lead to divergent allometric patterns of sexual characteristics that can have a sex-specific response.

Outbreaks, gene flow and effective population size in the migratory locust, Locusta migratoria: a regional-scale comparative survey.

PubMed

Chapuis, Marie-Pierre; Loiseau, Anne; Michalakis, Yannis; Lecoq, Michel; Franc, Alex; Estoup, Arnaud

2009-03-01

The potential effect of population outbreaks on within and between genetic variation of populations in pest species has rarely been assessed. In this study, we compare patterns of genetic variation in different sets of historically frequently outbreaking and rarely outbreaking populations of an agricultural pest of major importance, the migratory locust, Locusta migratoria. We analyse genetic variation within and between 24 populations at 14 microsatellites in Western Europe, where only ancient and low-intensity outbreaks have been reported (non-outbreaking populations), and in Madagascar and Northern China, where frequent and intense outbreak events have been recorded over the last century (outbreaking populations). Our comparative survey shows that (i) the long-term effective population size is similar in outbreaking and non-outbreaking populations, as evidenced by similar estimates of genetic diversity, and (ii) gene flow is substantially larger among outbreaking populations than among non-outbreaking populations, as evidenced by a fourfold to 30-fold difference in FST values. We discuss the implications for population dynamics and the consequences for management strategies of the observed patterns of genetic variation in L. migratoria populations with contrasting historical outbreak frequency and extent.

Disaster warning system study summary. [cost estimates using NOAA satellites

NASA Technical Reports Server (NTRS)

Leroy, B. F.; Maloy, J. E.; Braley, R. C.; Provencher, C. E.; Schumaker, H. A.; Valgora, M. E.

1977-01-01

A conceptual satellite system to replace or complement NOAA's data collection, internal communications, and public information dissemination systems for the mid-1980's was defined. Program cost and cost sensitivity to variations in communications functions are analyzed.

Using science to improve communications about suicide among military and veteran populations: looking for a few good messages.

PubMed

Langford, Linda; Litts, David; Pearson, Jane L

2013-01-01

Concern about suicide in US military and veteran populations has prompted efforts to identify more effective prevention measures. Recent expert panel reports have recommended public communications as one component of a comprehensive effort. Messaging about military and veteran suicide originates from many sources and often does not support suicide prevention goals or adhere to principles for developing effective communications. There is an urgent need for strategic, science-based, consistent messaging guidance in this area. Although literature on the effectiveness of suicide prevention communications for these populations is lacking, this article summarizes key findings from several bodies of research that offer lessons for creating safe and effective messages that support and enhance military and veteran suicide prevention efforts.

Investigating executive functions in children with severe speech and movement disorders using structured tasks.

PubMed

Stadskleiv, Kristine; von Tetzchner, Stephen; Batorowicz, Beata; van Balkom, Hans; Dahlgren-Sandberg, Annika; Renner, Gregor

2014-01-01

Executive functions are the basis for goal-directed activity and include planning, monitoring, and inhibition, and language seems to play a role in the development of these functions. There is a tradition of studying executive function in both typical and atypical populations, and the present study investigates executive functions in children with severe speech and motor impairments who are communicating using communication aids with graphic symbols, letters, and/or words. There are few neuropsychological studies of children in this group and little is known about their cognitive functioning, including executive functions. It was hypothesized that aided communication would tax executive functions more than speech. Twenty-nine children using communication aids and 27 naturally speaking children participated. Structured tasks resembling everyday activities, where the action goals had to be reached through communication with a partner, were used to get information about executive functions. The children (a) directed the partner to perform actions like building a Lego tower from a model the partner could not see and (b) gave information about an object without naming it to a person who had to guess what object it was. The executive functions of planning, monitoring, and impulse control were coded from the children's on-task behavior. Both groups solved most of the tasks correctly, indicating that aided communicators are able to use language to direct another person to do a complex set of actions. Planning and lack of impulsivity was positively related to task success in both groups. The aided group completed significantly fewer tasks, spent longer time and showed more variation in performance than the comparison group. The aided communicators scored lower on planning and showed more impulsivity than the comparison group, while both groups showed an equal degree of monitoring of the work progress. The results are consistent with the hypothesis that aided language tax executive functions more than speech. The results may also indicate that aided communicators have less experience with these kinds of play activities. The findings broaden the perspective on executive functions and have implications for interventions for motor-impaired children developing aided communication.

Investigating executive functions in children with severe speech and movement disorders using structured tasks

PubMed Central

Stadskleiv, Kristine; von Tetzchner, Stephen; Batorowicz, Beata; van Balkom, Hans; Dahlgren-Sandberg, Annika; Renner, Gregor

2014-01-01

Executive functions are the basis for goal-directed activity and include planning, monitoring, and inhibition, and language seems to play a role in the development of these functions. There is a tradition of studying executive function in both typical and atypical populations, and the present study investigates executive functions in children with severe speech and motor impairments who are communicating using communication aids with graphic symbols, letters, and/or words. There are few neuropsychological studies of children in this group and little is known about their cognitive functioning, including executive functions. It was hypothesized that aided communication would tax executive functions more than speech. Twenty-nine children using communication aids and 27 naturally speaking children participated. Structured tasks resembling everyday activities, where the action goals had to be reached through communication with a partner, were used to get information about executive functions. The children (a) directed the partner to perform actions like building a Lego tower from a model the partner could not see and (b) gave information about an object without naming it to a person who had to guess what object it was. The executive functions of planning, monitoring, and impulse control were coded from the children's on-task behavior. Both groups solved most of the tasks correctly, indicating that aided communicators are able to use language to direct another person to do a complex set of actions. Planning and lack of impulsivity was positively related to task success in both groups. The aided group completed significantly fewer tasks, spent longer time and showed more variation in performance than the comparison group. The aided communicators scored lower on planning and showed more impulsivity than the comparison group, while both groups showed an equal degree of monitoring of the work progress. The results are consistent with the hypothesis that aided language tax executive functions more than speech. The results may also indicate that aided communicators have less experience with these kinds of play activities. The findings broaden the perspective on executive functions and have implications for interventions for motor-impaired children developing aided communication. PMID:25249999

Understanding human DNA sequence variation.

PubMed

Kidd, K K; Pakstis, A J; Speed, W C; Kidd, J R

2004-01-01

Over the past century researchers have identified normal genetic variation and studied that variation in diverse human populations to determine the amounts and distributions of that variation. That information is being used to develop an understanding of the demographic histories of the different populations and the species as a whole, among other studies. With the advent of DNA-based markers in the last quarter century, these studies have accelerated. One of the challenges for the next century is to understand that variation. One component of that understanding will be population genetics. We present here examples of many of the ways these new data can be analyzed from a population perspective using results from our laboratory on multiple individual DNA-based polymorphisms, many clustered in haplotypes, studied in multiple populations representing all major geographic regions of the world. These data support an "out of Africa" hypothesis for human dispersal around the world and begin to refine the understanding of population structures and genetic relationships. We are also developing baseline information against which we can compare findings at different loci to aid in the identification of loci subject, now and in the past, to selection (directional or balancing). We do not yet have a comprehensive understanding of the extensive variation in the human genome, but some of that understanding is coming from population genetics.

Posture variation among office workers when using different information and communication technologies at work and away from work.

PubMed

Ciccarelli, Marina; Straker, Leon; Mathiassen, Svend Erik; Pollock, Clare

2014-01-01

Office workers perform tasks using different information and communication technologies (ICT) involving various postures. Adequate variation in postures and muscle activity is generally believed to protect against musculoskeletal complaints, but insufficient information exists regarding the effect on postural variation of using different ICT. Thus, this study among office workers aimed to determine and compare postures and postural variation associated with using distinct types of ICT. Upper arm, head and trunk postures of 24 office workers were measured with the Physiometer over a whole day in their natural work and away-from-work environments. Postural variation was quantified using two indices: APDF(90-10) and EVA(sd). Various ICT had different postural means and variation. Paper-based tasks had more non-neutral, yet also more variable postures. Electronics-based tasks had more neutral postures, with less postural variability. Tasks simultaneously using paper- and electronics-based ICT had least neutral and least variable postures. Tasks without ICT usually had the most posture variability. Interspersing tasks involving different ICT could increase overall exposure variation among office workers and may thus contribute to musculoskeletal risk reduction.

Genetic diversity affects the strength of population regulation in a marine fish.

PubMed

Johnson, D W; Freiwald, J; Bernardi, G

2016-03-01

Variation is an essential feature of biological populations, yet much of ecological theory treats individuals as though they are identical. This simplifying assumption is often justified by the perception that variation among individuals does not have significant effects on the dynamics of whole populations. However, this perception may be skewed by a historic focus on studying single populations. A true evaluation of the extent to which among-individual variation affects the dynamics of populations requires the study of multiple populations. In this study, we examined variation in the dynamics of populations of a live-bearing, marine fish (black surfperch; Embiotoca jacksoni). In collaboration with an organization of citizen scientists (Reef Check California), we were able to examine the dynamics of eight populations that were distributed throughout approximately 700 km of coastline, a distance that encompasses much of this species' range. We hypothesized that genetic variation within a local population would be related to the intensity of competition and to the strength of population regulation. To test this hypothesis, we examined whether genetic diversity (measured by the diversity of mitochondrial DNA haplotypes) was related to the strength of population regulation. Low-diversity populations experienced strong density dependence in population growth rates and population sizes were regulated much more tightly than they were in high-diversity populations. Mechanisms that contributed to this pattern include links between genetic diversity, habitat use, and spatial crowding. On average, low-diversity populations used less of the available habitat and exhibited greater spatial clustering (and more intense competition) for a given level of density (measured at the scale of the reef). Although the populations we studied also varied with respect to exogenous characteristics (habitat complexity, densities of predators, and interspecific competitors), none of these characteristics was significantly related to the strength of population regulation. In contrast, an endogenous characteristic of the population (genetic diversity) explained 77% of the variation in the strength of population regulation (95% CI: 27-94%). Our results suggest that the genetic and phenotypic composition of populations can play a major role in their dynamics.

The role of culture in effective HIV/AIDS communication by theatre in South Africa.

PubMed

Uwah, Chijioke

2013-01-01

The need to effectively communicate HIV/AIDS messages in South Africa, given the high prevalence of the pandemic, cannot be overemphasised. Communication scholars have long emphasised the need to recognise adherence to cultural norms of target communities as catalyst for effective HIV/AIDS communication. Unfortunately this call has not been totally heeded by the designers of HIV/AIDS communication instruments. In the case of theatre, research has shown that in South Africa, theatre groups have gone into communities with pre-packaged plays without due cognisance of the cultural norms and beliefs of the target population. This research was conducted in KwaZulu-Natal (the province with the highest prevalence rate of HIV/AIDS infection in South Africa). Using a qualitative research methodology this paper investigated the inclusion/non-inclusion of the cultural norms of the target population in the design of the dramatic performance by the theatre group in its HIV/AIDS campaigns. The findings indicate that while the group did try to incorporate aspects of the cultural norms of the target population, it did so at a level that failed to effectively communicate the HIV/AIDS message to its audiences. This paper therefore seeks to show through empirical evidence that the non-inclusion of cultural norms and values of the target population has acted as a stumbling block in the effective communication of HIV/AIDS messages by theatre groups in the country.

Prevalence and etiologies of adult communication disabilities in the United States: Results from the 2012 National Health Interview Survey.

PubMed

Morris, Megan A; Meier, Sarah K; Griffin, Joan M; Branda, Megan E; Phelan, Sean M

2016-01-01

Communication disabilities, including speech, language and voice disabilities, can significantly impact a person's quality of life, employment and health status. Despite this, little is known about the prevalence and etiology of communication disabilities in the general adult population. To assess the prevalence and etiology of communication disabilities in a nationally representative adult sample. We conducted a cross-sectional study and analyzed the responses of non-institutionalized adults to the Sample Adult Core questionnaire within the 2012 National Health Interview Survey. We used respondents' self-report of having a speech, language or voice disability within the past year and receiving a diagnosis for one of these communication disabilities, as well as the etiology of their communication disability. We additionally examined the responses by subgroups, including sex, age, race and ethnicity, and geographical area. In 2012 approximately 10% of the US adult population reported a communication disability, while only 2% of adults reported receiving a diagnosis. The rates of speech, language and voice disabilities and diagnoses varied across gender, race/ethnicity and geographic groups. The most common response for the etiology of a communication disability was "something else." Improved understanding of population prevalence and etiologies of communication disabilities will assist in appropriately directing rehabilitation and medical services; potentially reducing the burden of communication disabilities. Copyright © 2016 Elsevier Inc. All rights reserved.

High MHC diversity maintained by balancing selection in an otherwise genetically monomorphic mammal

PubMed Central

Aguilar, Andres; Roemer, Gary; Debenham, Sally; Binns, Matthew; Garcelon, David; Wayne, Robert K.

2004-01-01

The San Nicolas Island fox (Urocyon littoralis dickeyi) is genetically the most monomorphic sexually reproducing animal population yet reported and has no variation in hypervariable genetic markers. Such low levels of variation imply lower resistance to pathogens, reduced fitness, and problems in distinguishing kin from non-kin. In vertebrates, the MHC contains genes that influence disease resistance and kin recognition and may be under intense balancing selection in some populations. Hence, genetic variation at the MHC might persist despite the extreme monomorphism shown by neutral markers. We examine variation of five loci within the MHC of San Nicolas Island foxes and find remarkably high levels of variation. Further, we show by simulation that genetic monomorphism at neutral loci and high MHC variation could arise only through an extreme population bottleneck of <10 individuals, ≈10–20 generations ago, accompanied by unprecedented selection coefficients of >0.5 on MHC loci. These results support the importance of balancing selection as a mechanism to maintain variation in natural populations and expose the difficulty of using neutral markers as surrogates for variation in fitness-related loci. PMID:14990802

Synchronous population dynamics in California butterflies explained by climatic forcing

PubMed Central

Shapiro, Arthur M.

2017-01-01

A long-standing challenge for population biology has been to understand why some species are characterized by populations that fluctuate in size independently, while populations of other species fluctuate synchronously across space. The effects of climatic variation and dispersal have been invoked to explain synchronous population dynamics, however an understanding of the relative influence of these drivers in natural populations is lacking. Here we compare support for dispersal- versus climate-driven models of interspecific variation in synchrony using 27 years of observations of 65 butterfly species at 10 sites spanning 2750 m of elevation in Northern California. The degree of spatial synchrony exhibited by each butterfly species was used as a response in a unique approach that allowed us to investigate whether interspecific variation in response to climate or dispersal propensity was most predictive of interspecific variation in synchrony. We report that variation in sensitivity to climate explained 50% of interspecific variation in synchrony, whereas variation in dispersal propensity explained 23%. Sensitivity to the El Niño Southern Oscillation, a primary driver of regional climate, was the best predictor of synchrony. Combining sensitivity to climate and dispersal propensity into a single model did not greatly increase model performance, confirming the primacy of climatic sensitivity for driving spatial synchrony in butterflies. Finally, we uncovered a relationship between spatial synchrony and population decline that is consistent with theory, but small in magnitude, which suggests that the degree to which populations fluctuate in synchrony is of limited use for understanding the ongoing decline of the Northern California butterfly fauna. PMID:28791146

Mutualists and antagonists drive among-population variation in selection and evolution of floral display in a perennial herb

PubMed Central

Ågren, Jon; Hellström, Frida; Toräng, Per; Ehrlén, Johan

2013-01-01

Spatial variation in the direction of selection drives the evolution of adaptive differentiation. However, few experimental studies have examined the relative importance of different environmental factors for variation in selection and evolutionary trajectories in natural populations. Here, we combine 8 y of observational data and field experiments to assess the relative importance of mutualistic and antagonistic interactions for spatial variation in selection and short-term evolution of a genetically based floral display dimorphism in the short-lived perennial herb Primula farinosa. Natural populations of this species include two floral morphs: long-scaped plants that present their flowers well above the ground and short-scaped plants with flowers positioned close to the ground. The direction and magnitude of selection on scape morph varied among populations, and so did the frequency of the short morph (median 19%, range 0–100%; n = 69 populations). A field experiment replicated at four sites demonstrated that variation in the strength of interactions with grazers and pollinators were responsible for among-population differences in relative fitness of the two morphs. Selection exerted by grazers favored the short-scaped morph, whereas pollinator-mediated selection favored the long-scaped morph. Moreover, variation in selection among natural populations was associated with differences in morph frequency change, and the experimental removal of grazers at nine sites significantly reduced the frequency of the short-scaped morph over 8 y. The results demonstrate that spatial variation in intensity of grazing and pollination produces a selection mosaic, and that changes in biotic interactions can trigger rapid genetic changes in natural plant populations. PMID:24145439

Mutualists and antagonists drive among-population variation in selection and evolution of floral display in a perennial herb.

PubMed

Agren, Jon; Hellström, Frida; Toräng, Per; Ehrlén, Johan

2013-11-05

Spatial variation in the direction of selection drives the evolution of adaptive differentiation. However, few experimental studies have examined the relative importance of different environmental factors for variation in selection and evolutionary trajectories in natural populations. Here, we combine 8 y of observational data and field experiments to assess the relative importance of mutualistic and antagonistic interactions for spatial variation in selection and short-term evolution of a genetically based floral display dimorphism in the short-lived perennial herb Primula farinosa. Natural populations of this species include two floral morphs: long-scaped plants that present their flowers well above the ground and short-scaped plants with flowers positioned close to the ground. The direction and magnitude of selection on scape morph varied among populations, and so did the frequency of the short morph (median 19%, range 0-100%; n = 69 populations). A field experiment replicated at four sites demonstrated that variation in the strength of interactions with grazers and pollinators were responsible for among-population differences in relative fitness of the two morphs. Selection exerted by grazers favored the short-scaped morph, whereas pollinator-mediated selection favored the long-scaped morph. Moreover, variation in selection among natural populations was associated with differences in morph frequency change, and the experimental removal of grazers at nine sites significantly reduced the frequency of the short-scaped morph over 8 y. The results demonstrate that spatial variation in intensity of grazing and pollination produces a selection mosaic, and that changes in biotic interactions can trigger rapid genetic changes in natural plant populations.

Modeling the Transformational Communications System Urban Land Mobile Satellite Channel

DTIC Science & Technology

2007-12-01

interference of time - delayed signals). The “slow” variations are usually associated with specific shadowing events by foliage, terrain or buildings. The...by F. P. Fontan et al. [24].......................11 Figure 4. Short, medium and long-term variation of signal strength with time . Long- term...long-term variation of signal strength with time . Long- term (“very slow”) variation is modeled by state transitions shown in Figure 3. C

Online cancer communication: meeting the literacy, cultural and linguistic needs of diverse audiences.

PubMed

Neuhauser, Linda; Kreps, Gary L

2008-06-01

This article provides an analysis of issues and empirical evidence related to literacy, cultural, and linguistic factors in online health and cancer communication, and recommendations to improve cancer communication for diverse audiences. We examined English-language online literature and selected books and policy documents related to literacy, cultural, and linguistic factors in health and cancer communication. Studies about literacy, cultural, and linguistic factors in online cancer communication for diverse audiences are limited, but have increased during the past 15 years. Empirical evidence and theoretical guidance describe the critical importance of these factors, significant unmet needs among low-literate, multicultural and non-English-speaking populations, and strategies to improve communication. Overall, online cancer communication has not met the literacy, cultural, and linguistic needs of diverse populations. The literature offers valuable recommendations about enhancing research, practice, and policy for better cancer communication. Practitioners should understand the strengths and weaknesses of online cancer communication for vulnerable groups, guide patients to better Websites, and supplement that information with oral and tailored communication.

Genetic variation and differentiation in parent-descendant cattle and bison populations

USDA-ARS?s Scientific Manuscript database

Genetic variation and differentiation at 32 microsatellite DNA loci is quantified for parent-descendant cattle populations and parent-descendant bison (Bison bison) populations. Heterozygosity (Ho) and numbers of alleles/locus (AR) are less in the Line 1 Hereford inbred cattle population than in t...

Fleeing to Fault Zones: Incorporating Syrian Refugees into Earthquake Risk Analysis along the East Anatolian and Dead Sea Rift Fault Zones

NASA Astrophysics Data System (ADS)

Wilson, B.; Paradise, T. R.

2016-12-01

The influx of millions of Syrian refugees into Turkey has rapidly changed the population distribution along the Dead Sea Rift and East Anatolian Fault zones. In contrast to other countries in the Middle East where refugees are accommodated in camp environments, the majority of displaced individuals in Turkey are integrated into cities, towns, and villages—placing stress on urban settings and increasing potential exposure to strong shaking. Yet, displaced populations are not traditionally captured in data sources used in earthquake risk analysis or loss estimations. Accordingly, we present a district-level analysis assessing the spatial overlap of earthquake hazards and refugee locations in southeastern Turkey to determine how migration patterns are altering seismic risk in the region. Using migration estimates from the U.S. Humanitarian Information Unit, we create three district-level population scenarios that combine official population statistics, refugee camp populations, and low, median, and high bounds for integrated refugee populations. We perform probabilistic seismic hazard analysis alongside these population scenarios to map spatial variations in seismic risk between 2011 and late 2015. Our results show a significant relative southward increase of seismic risk for this period due to refugee migration. Additionally, we calculate earthquake fatalities for simulated earthquakes using a semi-empirical loss estimation technique to determine degree of under-estimation resulting from forgoing migration data in loss modeling. We find that including refugee populations increased casualties by 11-12% using median population estimates, and upwards of 20% using high population estimates. These results communicate the ongoing importance of placing environmental hazards in their appropriate regional and temporal context which unites physical, political, cultural, and socio-economic landscapes. Keywords: Earthquakes, Hazards, Loss-Estimation, Syrian Crisis, Migration, Refugees

Is variation in susceptibility to Phytophthora ramorum correlated with population genetic structure in coast live oak (Quercus agrifolia)?

PubMed

Dodd, Richard S; Hüberli, Daniel; Douhovnikoff, Vlad; Harnik, Tamar Y; Afzal-Rafii, Zara; Garbelotto, Matteo

2005-01-01

California coastal woodlands are suffering severe disease and mortality as a result of infection from Phytophthora ramorum. Quercus agrifolia is one of the major woodland species at risk. This study investigated within- and among-population variation in host susceptibility to inoculation with P. ramorum and compared this with population genetic structure using molecular markers. Susceptibility was assessed using a branch-cutting inoculation test. Trees were selected from seven natural populations in California. Amplified fragment length polymorphism molecular markers were analysed for all trees used in the trials. Lesion sizes varied quantitatively among individuals within populations, with up to an eightfold difference. There was little support for population differences in susceptibility. Molecular structure also showed a strong within-population, and weaker among-population, pattern of variation. Our data suggest that susceptibility of Q. agrifolia to P. ramorum is variable and is under the control of several gene loci. This variation exists within populations, so that less susceptible local genotypes may provide the gene pool for regeneration of woodlands where mortality is high.

[Ionizing and non-ionizing radiation (comparative risk estimations)].

PubMed

Grigor'ev, Iu G

2012-01-01

The population has widely used mobile communication for already more than 15 years. It is important to note that the use of mobile communication has sharply changed the conditions of daily exposure of the population to EME We expose our brain daily for the first time in the entire civilization. The mobile phone is an open and uncontrollable source of electromagnetic radiation. The comparative risk estimation for the population of ionizing and non-ionizing radiation was carried out taking into account the real conditions of influence. Comparison of risks for the population of ionizing and non-ionizing radiation leads us to a conclusion that EMF RF exposure in conditions of wide use of mobile communication is potentially more harmful than ionizing radiation influence.

Additive genetic variation and evolvability of a multivariate trait can be increased by epistatic gene action.

PubMed

Griswold, Cortland K

2015-12-21

Epistatic gene action occurs when mutations or alleles interact to produce a phenotype. Theoretically and empirically it is of interest to know whether gene interactions can facilitate the evolution of diversity. In this paper, we explore how epistatic gene action affects the additive genetic component or heritable component of multivariate trait variation, as well as how epistatic gene action affects the evolvability of multivariate traits. The analysis involves a sexually reproducing and recombining population. Our results indicate that under stabilizing selection conditions a population with a mixed additive and epistatic genetic architecture can have greater multivariate additive genetic variation and evolvability than a population with a purely additive genetic architecture. That greater multivariate additive genetic variation can occur with epistasis is in contrast to previous theory that indicated univariate additive genetic variation is decreased with epistasis under stabilizing selection conditions. In a multivariate setting, epistasis leads to less relative covariance among individuals in their genotypic, as well as their breeding values, which facilitates the maintenance of additive genetic variation and increases a population׳s evolvability. Our analysis involves linking the combinatorial nature of epistatic genetic effects to the ancestral graph structure of a population to provide insight into the consequences of epistasis on multivariate trait variation and evolution. Copyright © 2015 Elsevier Ltd. All rights reserved.

Using Science to Improve Communications About Suicide Among Military and Veteran Populations: Looking for a Few Good Messages

PubMed Central

Litts, David; Pearson, Jane L.

2013-01-01

Concern about suicide in US military and veteran populations has prompted efforts to identify more effective prevention measures. Recent expert panel reports have recommended public communications as one component of a comprehensive effort. Messaging about military and veteran suicide originates from many sources and often does not support suicide prevention goals or adhere to principles for developing effective communications. There is an urgent need for strategic, science-based, consistent messaging guidance in this area. Although literature on the effectiveness of suicide prevention communications for these populations is lacking, this article summarizes key findings from several bodies of research that offer lessons for creating safe and effective messages that support and enhance military and veteran suicide prevention efforts. PMID:23153130

Epidemics after Natural Disasters

PubMed Central

Gayer, Michelle; Connolly, Maire A.

2007-01-01

The relationship between natural disasters and communicable diseases is frequently misconstrued. The risk for outbreaks is often presumed to be very high in the chaos that follows natural disasters, a fear likely derived from a perceived association between dead bodies and epidemics. However, the risk factors for outbreaks after disasters are associated primarily with population displacement. The availability of safe water and sanitation facilities, the degree of crowding, the underlying health status of the population, and the availability of healthcare services all interact within the context of the local disease ecology to influence the risk for communicable diseases and death in the affected population. We outline the risk factors for outbreaks after a disaster, review the communicable diseases likely to be important, and establish priorities to address communicable diseases in disaster settings. PMID:17370508

Quantitative Aspects of Communicative Impairment Ascertained in a Large National Survey of Japanese Children.

PubMed

Oi, Manabu; Fujino, Hiroshi; Tsukidate, Naotake; Kamio, Yoko; Yoshimura, Yuko; Kikuchi, Mitsuru; Hasegawa, Chiaki; Gondou, Keiko; Matsui, Tomoko

2017-10-01

The Japanese version of the Children's Communication Checklist-2 (CCC-2) was rated by caregivers in a large national population sample of 22,871 children aged 3-15 years. The General Communication Composite (GCC) of the CCC-2 exhibited a distribution with a single-factor structure. The GCC distribution between autism spectrum disorders (ASD) and language impairment (LI) groups in the general population fit inside a bell curve with significant overlap with the general population, and a continuum was evident between groups. No evidence of a natural cutoff that would differentiate categorically affected from unaffected children was seen. The Social Interaction Deviance Composite (SIDC) supported the notion that ASD and LI are on the opposite endpoints of a SIDC continuum of communication impairment.

Climate warming: a loss of variation in populations can accompany reproductive shifts.

PubMed

Massot, Manuel; Legendre, Stéphane; Fédérici, Pierre; Clobert, Jean

2017-09-01

The most documented response of organisms to climate warming is a change in the average timing of seasonal activities (phenology). Although we know that these average changes can differ among species and populations, we do not know whether climate warming impacts within-population variation in phenology. Using data from five study sites collected during a 13-year survey, we found that the increase in spring temperatures is associated with a reproductive advance of 10 days in natural populations of common lizards (Zootoca vivipara). Interestingly, we show a correlated loss of variation in reproductive dates within populations. As illustrated by a model, this shortening of the reproductive period can have significant negative effects on population dynamics. Consequently, we encourage tests in other species to assess the generality of decreased variation in phenological responses to climate change. © 2017 The Authors Ecology Letters published by CNRS and John Wiley & Sons Ltd.

Assessment of state- and territorial-level preparedness capacity for serving deaf and hard-of-hearing populations in disasters.

PubMed

Ivey, Susan L; Tseng, Winston; Dahrouge, Donna; Engelman, Alina; Neuhauser, Linda; Huang, Debbie; Gurung, Sidhanta

2014-01-01

Substantial evidence exists that emergency preparedness and response efforts are not effectively reaching populations with functional and access needs, especially barriers related to literacy, language, culture, or disabilities. More than 36 million Americans are Deaf or hard of hearing (Deaf/HH). These groups experienced higher risks of injury, death, and property loss in recent disasters than the general public. We conducted a participatory research study to examine national recommendations on preparedness communication for the Deaf/HH. We assessed whether previous recommendations regarding the Deaf/HH have been incorporated into state- and territorial-level emergency operations plans (EOPs), interviewed state- and territorial-level preparedness directors about capacity to serve the Deaf/HH, and proposed strategies to benefit Deaf/HH populations during emergencies. We analyzed 55 EOPs and 50 key informant (KI) interviews with state directors. Fifty-five percent of EOPs mentioned vulnerable populations; however, only 31% specifically mentioned Deaf/HH populations in their plan. Study findings indicated significant relationships among the following factors: a state-level KI's familiarity with communication issues for the Deaf/HH, making relay calls (i.e., calls to services to relay communication between Deaf and hearing people), and whether the KI's department provides trainings about serving Deaf/HH populations in emergencies. We found significant associations between a state's percentage of Deaf/HH individuals and a KI's familiarity with Deaf/HH communication issues and provision by government of any disability services to Deaf/HH populations in emergencies. Further, we found significant relationships between KIs attending training on serving the Deaf/HH and familiarity with Deaf/HH communication issues, including how to make relay calls. This study provides new knowledge that can help emergency agencies improve their preparedness training, planning, and capacity to serve Deaf/HH populations in emergencies.

Childhood lead poisoning in a Somali refugee resettlement community in New Hampshire.

PubMed

Caron, Rosemary M; Tshabangu-Soko, Thandi; Finefrock, Krysten

2013-08-01

Despite the gradual decrease in childhood lead poisoning in the United States, the risk for lead poisoning among African refugee children who resettle in the United States remains elevated. Communication methods implemented by resettlement agencies in the public health system for preventing childhood lead poisoning in this at-risk population warrant further investigation. We utilized structured interviews with key stakeholders (resettlement agencies, social service agencies developed by African refugees and resettled Somali refugees) involved in the refugee resettlement process to (1) describe the agency's role in the refugee resettlement process; (2) examine communication methods utilized and barriers experienced by the public health system in reference to childhood lead poisoning; (3) describe the refugee population's perception of childhood lead poisoning; (4) examine general challenges experienced by the public health system and the refugee population during the resettlement process; and (5) describe stakeholders' recommendations to improve health communication efforts. Based on our findings, we propose that communities are important determinants in health-related problems for refugee populations. Each community has its own environment and public health system that interacts with each other to influence health risks and risk perceptions of its populations. We advocate that understanding a community's ecology and implementing a culture-centered approach is essential for the public health system to help educate and prevent communication inequalities and health disparities among an at-risk African refugee population. This action can reduce a population's resistance to communication and help build a community's capacity to address a persistent public health problem, such as childhood lead poisoning.

A new concept and classification of corona mortis and its clinical significance.

PubMed

Al Talalwah, Waseem

2016-10-01

The obturator artery and its accessory (aberrant) arising from different origins and crossing the pubic rami are vascular variations. The internal iliac artery usually provides the obturator artery which may communicates with the external iliac artery through either the accessory obturator or inferior epigastric artery. A collateral circulation between the external and internal iliac system is known as corona mortis. The aim of current study is to provide sufficient data of vascular variability crossing the pubic rami for clinical field. Present study includes 208 hemipelvises dissected in the Institution of Anatomy, Medical University of Graz. During dissection, the obturator artery and its accessory crossing the superior rami of pubic bone were found to have different origins. The obturator artery arising from the external iliac artery and from the femoral artery accounts for 9.8% and 1.1% respectively. Therefore, it passes over the superior pubic rami in 10.9%. Further, the accessory (aberrant) artery arises only from the femoral artery in 1.1%. In present study, the vascular variation crossing the superior pubic rami with or without collateral circulation between external and internal iliac system referred as corona mortis is addressed. This study includes new classification of obturator and accessory obturator arteries as well as the corona mortis. It includes a comparison of corona mortis incidence in Austria population and other populations. The corona mortis found to be in 12% of Austrian population. A great attention of clinicians, radiologists, surgeons, orthopedic surgeons, obstetricians and gynecologists has to be considered before pubic surgical procedures such as internal fixation of pubic fracture, an inguinal hernia repair. Further, traumatic pubic rami fracture may lead to massive hemor- rhage due to laceration of the obturator artery.

Risk communication in the hyperacute setting of stroke thrombolysis: an interview study of clinicians.

PubMed

Lie, M L S; Murtagh, M J; Watson, D Burges; Jenkings, K N; Mackintosh, J; Ford, G A; Thomson, R G

2015-05-01

Communicating treatment risks and benefits to patients and their carers is central to clinical practice in modern healthcare. We investigated the challenges of risk communication by clinicians offering thrombolytic therapy for hyperacute stroke where treatment must be administered rapidly to maximise benefit. Semistructured interviews with 13 clinicians from three acute stroke units involved in decision making and/or information provision about thrombolysis. We report on clinicians' accounts of communicating risks and benefits to patients and carers. Framework analysis was employed. We identified the major challenges facing clinicians in communicating risk in this context that is, disease complexity, patients' capacity and time constraints, and communicating quality of life after stroke. We found significant variation in the data on risks and benefits that clinicians provide, and ways these were communicated to patients. Clinicians' communication strategies varied and included practices such as: a phased approach to communicating information, being responsive to the patient and family and documenting information they gave to patients. Risk communication about thrombolysis involves complex uncertainties. We elucidate the challenges of effective risk communication in a hyperacute setting and identify the issues regarding variation in risk communication and the use of less effective formats for the communication of numerical risks and benefits. The paper identifies good practice, such as the phased transfer of information over the care pathway, and ways in which clinicians might be supported to overcome challenges. This includes standardised risk and benefit information alongside appropriate personalisation of risk communication. Effective risk communication in emergency settings requires presentation of high-quality data which is amenable to tailoring to individual patients' circumstances. It necessitates clinical skills development supported by personalised risk communication tools. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.

Genetic variations in the Dravidian population of South West coast of India: Implications in designing case-control studies.

PubMed

D'Cunha, Anitha; Pandit, Lekha; Malli, Chaithra

2017-06-01

Indian data have been largely missing from genome-wide databases that provide information on genetic variations in different populations. This hinders association studies for complex disorders in India. This study was aimed to determine whether the complex genetic structure and endogamy among Indians could potentially influence the design of case-control studies for autoimmune disorders in the south Indian population. A total of 12 single nucleotide variations (SNVs) related to genes associated with autoimmune disorders were genotyped in 370 healthy individuals belonging to six different caste groups in southern India. Allele frequencies were estimated; genetic divergence and phylogenetic relationship within the various caste groups and other HapMap populations were ascertained. Allele frequencies for all genotyped SNVs did not vary significantly among the different groups studied. Wright's FSTwas 0.001 per cent among study population and 0.38 per cent when compared with Gujarati in Houston (GIH) population on HapMap data. The analysis of molecular variance results showed a 97 per cent variation attributable to differences within the study population and <1 per cent variation due to differences between castes. Phylogenetic analysis showed a separation of Dravidian population from other HapMap populations and particularly from GIH population. Despite the complex genetic origins of the Indian population, our study indicated a low level of genetic differentiation among Dravidian language-speaking people of south India. Case-control studies of association among Dravidians of south India may not require stratification based on language and caste.

Face-to-face communication between patients and family physicians in Canada: A scoping review.

PubMed

Armas, Alana; Meyer, Samantha B; Corbett, Kitty K; Pearce, Alex R

2018-05-01

Patient-provider communication is critical in primary care. Canada's unique health system, population distribution, and cultural context suggest there is value in addressing the topic in the Canadian context. We conducted a scoping review to synthesize recent Canadian literature to inform practice in primary care settings and identify research agendas for patient-provider communication in Canada. Using Arksey and O'Malley's framework we searched four literature databases: Medline, Web of Science, CINAHL and EMBASE. We extracted 21,932 articles published between 2010 and 2017. A total of 108 articles met the inclusion criteria. The articles were analyzed qualitatively using thematic analysis to identify major themes. Four major themes were identified: information sharing, relationships, health system challenges, and development and use of communication tools. Our review identified a need for Canadian research regarding: communication in primary care with Aboriginal, immigrant, and rural populations; the impact of medical tourism on primary care; and how to improve communication to facilitate continuity of care. Challenges providers face in primary care in Canada include: communicating with linguistically and culturally diverse populations; addressing issues that emerge with the rise of medical tourism; a need for decision aids to improve communication with patients. Copyright © 2017 Elsevier B.V. All rights reserved.

Dissection of complex adult traits in a mouse synthetic population.

PubMed

Burke, David T; Kozloff, Kenneth M; Chen, Shu; West, Joshua L; Wilkowski, Jodi M; Goldstein, Steven A; Miller, Richard A; Galecki, Andrzej T

2012-08-01

Finding the causative genetic variations that underlie complex adult traits is a significant experimental challenge. The unbiased search strategy of genome-wide association (GWAS) has been used extensively in recent human population studies. These efforts, however, typically find only a minor fraction of the genetic loci that are predicted to affect variation. As an experimental model for the analysis of adult polygenic traits, we measured a mouse population for multiple phenotypes and conducted a genome-wide search for effector loci. Complex adult phenotypes, related to body size and bone structure, were measured as component phenotypes, and each subphenotype was associated with a genomic spectrum of candidate effector loci. The strategy successfully detected several loci for the phenotypes, at genome-wide significance, using a single, modest-sized population (N = 505). The effector loci each explain 2%-10% of the measured trait variation and, taken together, the loci can account for over 25% of a trait's total population variation. A replicate population (N = 378) was used to confirm initially observed loci for one trait (femur length), and, when the two groups were merged, the combined population demonstrated increased power to detect loci. In contrast to human population studies, our mouse genome-wide searches find loci that individually explain a larger fraction of the observed variation. Also, the additive effects of our detected mouse loci more closely match the predicted genetic component of variation. The genetic loci discovered are logical candidates for components of the genetic networks having evolutionary conservation with human biology.

Body size and lean mass of brown bears across and within four diverse ecosystems

USGS Publications Warehouse

Hilderbrand, Grant V.; Gustine, David; Mangipane, Buck A.; Joly, Kyle; Leacock, William; Mangipane, Lindsey S.; Erlenbach, Joy; Sorum, Mathew; Cameron, Matthew; Belant, Jerrold L.; Cambier, Troy

2018-01-01

Variation in body size across populations of brown bears (Ursus arctos) is largely a function of the availability and quality of nutritional resources while plasticity within populations reflects utilized niche width with implications for population resiliency. We assessed skull size, body length, and lean mass of adult female and male brown bears in four Alaskan study areas that differed in climate, primary food resources, population density, and harvest regime. Full body-frame size, as evidenced by asymptotic skull size and body length, was achieved by 8 to 14 years of age across populations and sexes. Lean body mass of both sexes continued to increase throughout their life. Differences between populations existed for all morphological measures in both sexes, bears in ecosystems with abundant salmon were generally larger. Within all populations, broad variation was seen in body size measures of adults with females displaying roughly a 2-fold difference in lean mass and males showing a 3- to 4-fold difference. The high level of intraspecific variation seen across and within populations suggests the presence of multiple life-history strategies and niche variation relative to resource partitioning, risk tolerance or aversion, and competition. Further, this level of variation indicates broad potential to adapt to changes within a given ecosystem and across the species’ range.

Quantitative Genetic Architecture at Latitudinal Range Boundaries: Reduced Variation but Higher Trait Independence.

PubMed

Paccard, Antoine; Van Buskirk, Josh; Willi, Yvonne

2016-05-01

Species distribution limits are hypothesized to be caused by small population size and limited genetic variation in ecologically relevant traits, but earlier studies have not evaluated genetic variation in multivariate phenotypes. We asked whether populations at the latitudinal edges of the distribution have altered quantitative genetic architecture of ecologically relevant traits compared with midlatitude populations. We calculated measures of evolutionary potential in nine Arabidopsis lyrata populations spanning the latitudinal range of the species in eastern and midwestern North America. Environments at the latitudinal extremes have reduced water availability, and therefore plants were assessed under wet and dry treatments. We estimated genetic variance-covariance (G-) matrices for 10 traits related to size, development, and water balance. Populations at southern and northern distribution edges had reduced levels of genetic variation across traits, but their G-matrices were more spherical; G-matrix orientation was unrelated to latitude. As a consequence, the predicted short-term response to selection was at least as strong in edge populations as in central populations. These results are consistent with genetic drift eroding variation and reducing the effectiveness of correlational selection at distribution margins. We conclude that genetic variation of isolated traits poorly predicts the capacity to evolve in response to multivariate selection and that the response to selection may frequently be greater than expected at species distribution margins because of genetic drift.

Interindividual variability in the prevalence of OPRM1 and CYP2B6 gene variations may identify drug-susceptible populations.

PubMed

Bunten, H; Liang, W J; Pounder, D J; Seneviratne, C; Osselton, D

2011-09-01

Methadone is used worldwide for the treatment of heroin addiction; however, fatal poisonings are increasingly reported. The prevalence of CYP2B6 and μ-opioid receptor (OPRM1) gene variations were examined between a postmortem population where the deaths were associated with methadone and a live nondrug-using control population using Taqman™ SNP Genotyping assays. The CYP2B6*6 allele was higher in the postmortem population, but the difference was not significant (P = 0.92). The CYP2B6 T750C promoter variation was similar in frequency for both populations. Linkage between T750C and CYP2B6*6 was identified for both populations (P < 0.01). The prevalence of the OPRM1 A118G variation was significantly higher in the control population (P = 0.0046), which might indicate a protective mechanism against opioid toxicity. Individual susceptibility to methadone may be determined by screening for CYP2B6*6.

Drift, selection, or migration? Processes affecting genetic differentiation and variation along a latitudinal gradient in an amphibian.

PubMed

Cortázar-Chinarro, Maria; Lattenkamp, Ella Z; Meyer-Lucht, Yvonne; Luquet, Emilien; Laurila, Anssi; Höglund, Jacob

2017-08-14

Past events like fluctuations in population size and post-glacial colonization processes may influence the relative importance of genetic drift, migration and selection when determining the present day patterns of genetic variation. We disentangle how drift, selection and migration shape neutral and adaptive genetic variation in 12 moor frog populations along a 1700 km latitudinal gradient. We studied genetic differentiation and variation at a MHC exon II locus and a set of 18 microsatellites. Using outlier analyses, we identified the MHC II exon 2 (corresponding to the β-2 domain) locus and one microsatellite locus (RCO8640) to be subject to diversifying selection, while five microsatellite loci showed signals of stabilizing selection among populations. STRUCTURE and DAPC analyses on the neutral microsatellites assigned populations to a northern and a southern cluster, reflecting two different post-glacial colonization routes found in previous studies. Genetic variation overall was lower in the northern cluster. The signature of selection on MHC exon II was weaker in the northern cluster, possibly as a consequence of smaller and more fragmented populations. Our results show that historical demographic processes combined with selection and drift have led to a complex pattern of differentiation along the gradient where some loci are more divergent among populations than predicted from drift expectations due to diversifying selection, while other loci are more uniform among populations due to stabilizing selection. Importantly, both overall and MHC genetic variation are lower at northern latitudes. Due to lower evolutionary potential, the low genetic variation in northern populations may increase the risk of extinction when confronted with emerging pathogens and climate change.

Intra-population variation in activity ranges, diel patterns, movement rates, and habitat use of American alligators in a subtropical estuary

NASA Astrophysics Data System (ADS)

Rosenblatt, Adam E.; Heithaus, Michael R.; Mazzotti, Frank J.; Cherkiss, Michael; Jeffery, Brian M.

2013-12-01

Movement and habitat use patterns are fundamental components of the behaviors of mobile animals and help determine the scale and types of interactions they have with their environments. These behaviors are especially important to quantify for top predators because they can have strong effects on lower trophic levels as well as the wider ecosystem. Many studies of top predator movement and habitat use focus on general population level trends, which may overlook important intra-population variation in behaviors that now appear to be common. In an effort to better understand the prevalence of intra-population variation in top predator movement behaviors and the potential effects of such variation on ecosystem dynamics, we examined the movement and habitat use patterns of a population of adult American alligators (Alligator mississippiensis) in a subtropical estuary for nearly four years. We found that alligators exhibited divergent behaviors with respect to activity ranges, movement rates, and habitat use, and that individualized behaviors were stable over multiple years. We also found that the variations across the three behavioral metrics were correlated such that consistent behavioral types emerged, specifically more exploratory individuals and more sedentary individuals. Our study demonstrates that top predator populations can be characterized by high degrees of intra-population variation in terms of movement and habitat use behaviors that could lead to individuals filling different ecological roles in the same ecosystem. By extension, one-size-fits-all ecosystem and species-specific conservation and management strategies that do not account for potential intra-population variation in top predator behaviors may not produce the desired outcomes in all cases.

The marine side of a terrestrial carnivore: intra-population variation in use of allochthonous resources by arctic foxes.

PubMed

Tarroux, Arnaud; Bêty, Joël; Gauthier, Gilles; Berteaux, Dominique

2012-01-01

Inter-individual variation in diet within generalist animal populations is thought to be a widespread phenomenon but its potential causes are poorly known. Inter-individual variation can be amplified by the availability and use of allochthonous resources, i.e., resources coming from spatially distinct ecosystems. Using a wild population of arctic fox as a study model, we tested hypotheses that could explain variation in both population and individual isotopic niches, used here as proxy for the trophic niche. The arctic fox is an opportunistic forager, dwelling in terrestrial and marine environments characterized by strong spatial (arctic-nesting birds) and temporal (cyclic lemmings) fluctuations in resource abundance. First, we tested the hypothesis that generalist foraging habits, in association with temporal variation in prey accessibility, should induce temporal changes in isotopic niche width and diet. Second, we investigated whether within-population variation in the isotopic niche could be explained by individual characteristics (sex and breeding status) and environmental factors (spatiotemporal variation in prey availability). We addressed these questions using isotopic analysis and bayesian mixing models in conjunction with linear mixed-effects models. We found that: i) arctic fox populations can simultaneously undergo short-term (i.e., within a few months) reduction in both isotopic niche width and inter-individual variability in isotopic ratios, ii) individual isotopic ratios were higher and more representative of a marine-based diet for non-breeding than breeding foxes early in spring, and iii) lemming population cycles did not appear to directly influence the diet of individual foxes after taking their breeding status into account. However, lemming abundance was correlated to proportion of breeding foxes, and could thus indirectly affect the diet at the population scale.

The Marine Side of a Terrestrial Carnivore: Intra-Population Variation in Use of Allochthonous Resources by Arctic Foxes

PubMed Central

Tarroux, Arnaud; Bêty, Joël; Gauthier, Gilles; Berteaux, Dominique

2012-01-01

Inter-individual variation in diet within generalist animal populations is thought to be a widespread phenomenon but its potential causes are poorly known. Inter-individual variation can be amplified by the availability and use of allochthonous resources, i.e., resources coming from spatially distinct ecosystems. Using a wild population of arctic fox as a study model, we tested hypotheses that could explain variation in both population and individual isotopic niches, used here as proxy for the trophic niche. The arctic fox is an opportunistic forager, dwelling in terrestrial and marine environments characterized by strong spatial (arctic-nesting birds) and temporal (cyclic lemmings) fluctuations in resource abundance. First, we tested the hypothesis that generalist foraging habits, in association with temporal variation in prey accessibility, should induce temporal changes in isotopic niche width and diet. Second, we investigated whether within-population variation in the isotopic niche could be explained by individual characteristics (sex and breeding status) and environmental factors (spatiotemporal variation in prey availability). We addressed these questions using isotopic analysis and Bayesian mixing models in conjunction with linear mixed-effects models. We found that: i) arctic fox populations can simultaneously undergo short-term (i.e., within a few months) reduction in both isotopic niche width and inter-individual variability in isotopic ratios, ii) individual isotopic ratios were higher and more representative of a marine-based diet for non-breeding than breeding foxes early in spring, and iii) lemming population cycles did not appear to directly influence the diet of individual foxes after taking their breeding status into account. However, lemming abundance was correlated to proportion of breeding foxes, and could thus indirectly affect the diet at the population scale. PMID:22900021

Variation in spawning time promotes genetic variability in population responses to environmental change in a marine fish

PubMed Central

Hutchings, Jeffrey A

2015-01-01

Abstract The level of phenotypic plasticity displayed within a population (i.e. the slope of the reaction norm) reflects the short-term response of a population to environmental change, while variation in reaction norm slopes among populations reflects spatial variation in these responses. Thus far, studies of thermal reaction norm variation have focused on geographically driven adaptation among different latitudes, altitudes or habitats. Yet, thermal variability is a function of both space and time. For organisms that reproduce at different times of year, such variation has the potential to promote adaptive variability in thermal responses for critical early life stages. Using common-garden experiments, we examined the spatial scale of genetic variation in thermal plasticity for early life-history traits among five populations of endangered Atlantic cod (Gadus morhua) that spawn at different times of year. Patterns of plasticity for larval growth and survival suggest that population responses to climate change will differ substantially, with increasing water temperatures posing a considerably greater threat to autumn-spawning cod than to those that spawn in winter or spring. Adaptation to seasonal cooling or warming experienced during the larval stage is suggested as a possible cause. Furthermore, populations that experience relatively cold temperatures during early life might be more sensitive to changes in temperature. Substantial divergence in adaptive traits was evident at a smaller spatial scale than has previously been shown for a marine fish with no apparent physical barriers to gene flow (∼200 km). Our findings highlight the need to consider the impact of intraspecific variation in reproductive timing on thermal adaptation when forecasting the effects of climate change on animal populations. PMID:27293712

Variation in spawning time promotes genetic variability in population responses to environmental change in a marine fish.

PubMed

Oomen, Rebekah A; Hutchings, Jeffrey A

2015-01-01

The level of phenotypic plasticity displayed within a population (i.e. the slope of the reaction norm) reflects the short-term response of a population to environmental change, while variation in reaction norm slopes among populations reflects spatial variation in these responses. Thus far, studies of thermal reaction norm variation have focused on geographically driven adaptation among different latitudes, altitudes or habitats. Yet, thermal variability is a function of both space and time. For organisms that reproduce at different times of year, such variation has the potential to promote adaptive variability in thermal responses for critical early life stages. Using common-garden experiments, we examined the spatial scale of genetic variation in thermal plasticity for early life-history traits among five populations of endangered Atlantic cod (Gadus morhua) that spawn at different times of year. Patterns of plasticity for larval growth and survival suggest that population responses to climate change will differ substantially, with increasing water temperatures posing a considerably greater threat to autumn-spawning cod than to those that spawn in winter or spring. Adaptation to seasonal cooling or warming experienced during the larval stage is suggested as a possible cause. Furthermore, populations that experience relatively cold temperatures during early life might be more sensitive to changes in temperature. Substantial divergence in adaptive traits was evident at a smaller spatial scale than has previously been shown for a marine fish with no apparent physical barriers to gene flow (∼200 km). Our findings highlight the need to consider the impact of intraspecific variation in reproductive timing on thermal adaptation when forecasting the effects of climate change on animal populations.

Sex-biased survival predicts adult sex ratio variation in wild birds

PubMed Central

Székely, Tamás; Liker, András; Freckleton, Robert P.; Fichtel, Claudia; Kappeler, Peter M.

2014-01-01

Adult sex ratio (ASR) is a central concept in population demography and breeding system evolution, and has implications for population viability and biodiversity conservation. ASR exhibits immense interspecific variation in wild populations, although the causes of this variation have remained elusive. Using phylogenetic analyses of 187 avian species from 59 families, we show that neither hatching sex ratios nor fledging sex ratios correlate with ASR. However, sex-biased adult mortality is a significant predictor of ASR, and this relationship is robust to 100 alternative phylogenetic hypotheses, and potential ecological and life-history confounds. A significant component of adult mortality bias is sexual selection acting on males, whereas increased reproductive output predicts higher mortality in females. These results provide the most comprehensive insights into ASR variation to date, and suggest that ASR is an outcome of selective processes operating differentially on adult males and females. Therefore, revealing the causes of ASR variation in wild populations is essential for understanding breeding systems and population dynamics. PMID:24966308

Climate change implications and use of early warning systems for global dust storms

USGS Publications Warehouse

Harriman, Lindsey M.

2014-01-01

With increased changes in land cover and global climate, early detection and warning of dust storms in conjunction with effective and widespread information broadcasts will be essential to the prevention and mitigation of future risks and impacts. Human activities, seasonal variations and long-term climatic patterns influence dust storms. More research is needed to analyse these factors of dust mobilisation to create more certainty for the fate of vulnerable populations and ecosystems in the future. Early warning and communication systems, when in place and effectively implemented, can offer some relief to these vulnerable areas. As an issue that affects many regions of the world, there is a profound need to understand the potential changes and ultimately create better early warning systems for dust storms.

Introduction beyond a species range: a relationship between population origin, adaptive potential and plant performance.

PubMed

Volis, S; Ormanbekova, D; Yermekbayev, K; Song, M; Shulgina, I

2014-09-01

The adaptive potential of a population defines its importance for species survival in changing environmental conditions such as global climate change. Very few empirical studies have examined adaptive potential across species' ranges, namely, of edge vs core populations, and we are unaware of a study that has tested adaptive potential (namely, variation in adaptive traits) and measured performance of such populations in conditions not currently experienced by the species but expected in the future. Here we report the results of a Triticum dicoccoides population study that employed transplant experiments and analysis of quantitative trait variation. Two populations at the opposite edges of the species range (1) were locally adapted; (2) had lower adaptive potential (inferred from the extent of genetic quantitative trait variation) than the two core populations; and (3) were outperformed by the plants from the core population in the novel environment. The fact that plants from the species arid edge performed worse than plants from the more mesic core in extreme drought conditions beyond the present climatic envelope of the species implies that usage of peripheral populations for conservation purposes must be based on intensive sampling of among-population variation.

Genetic diversity and sex ratio of naked mole rat, Heterocephalus glaber, zoo populations.

PubMed

Chau, Linh M; Groh, Amy M; Anderson, Emily C; Alcala, Micaela O; Mendelson, Joseph R; Slade, Stephanie B; Kerns, Kenton; Sarro, Steve; Lusardi, Clinton; Goodisman, Michael A D

2018-05-01

The naked mole rat, Heterocephalus glaber, is a highly unusual mammal that displays a complex social system similar to that found in eusocial insects. Colonies of H. glaber are commonly maintained in zoo collections because they represent fascinating educational exhibits for the public. However, little is known about the genetic structure or sex ratio of captive populations of H. glaber. In this study, we developed a set of microsatellite markers to examine genetic variation in three captive zoo populations of H. glaber. We also studied sex ratio of these captive populations. Our goal was to determine levels of genetic variation within, and genetic differences between, captive populations of H. glaber. Overall, we found modest levels of genetic variation in zoo populations. We also uncovered little evidence for inbreeding within the captive populations. However, zoo populations did differ genetically, which may reflect the isolation of captive naked mole rat colonies. Finally, we found no evidence of biased sex ratios within colonies. Overall, our study documents levels of genetic variation and sex ratios in a captive eusocial mammalian population. Our results may provide insight into how to manage captive populations of H. glaber. © 2018 Wiley Periodicals, Inc.

The role of culture in effective HIV/AIDS communication by theatre in South Africa

PubMed Central

Uwah, Chijioke

2014-01-01

The need to effectively communicate HIV/AIDS messages in South Africa, given the high prevalence of the pandemic, cannot be overemphasised. Communication scholars have long emphasised the need to recognise adherence to cultural norms of target communities as catalyst for effective HIV/AIDS communication. Unfortunately this call has not been totally heeded by the designers of HIV/AIDS communication instruments. In the case of theatre, research has shown that in South Africa, theatre groups have gone into communities with pre-packaged plays without due cognisance of the cultural norms and beliefs of the target population. This research was conducted in KwaZulu-Natal (the province with the highest prevalence rate of HIV/AIDS infection in South Africa). Using a qualitative research methodology this paper investigated the inclusion/non-inclusion of the cultural norms of the target population in the design of the dramatic performance by the theatre group in its HIV/AIDS campaigns. The findings indicate that while the group did try to incorporate aspects of the cultural norms of the target population, it did so at a level that failed to effectively communicate the HIV/AIDS message to its audiences. This paper therefore seeks to show through empirical evidence that the non-inclusion of cultural norms and values of the target population has acted as a stumbling block in the effective communication of HIV/AIDS messages by theatre groups in the country. PMID:24697309

Patterns of molecular genetic variation among cat breeds.

PubMed

Menotti-Raymond, Marilyn; David, Victor A; Pflueger, Solveig M; Lindblad-Toh, Kerstin; Wade, Claire M; O'Brien, Stephen J; Johnson, Warren E

2008-01-01

Genetic variation in cat breeds was assessed utilizing a panel of short tandem repeat (STR) loci genotyped in 38 cat breeds and 284 single-nucleotide polymorphisms (SNPs) genotyped in 24 breeds. Population structure in cat breeds generally reflects their recent ancestry and absence of strong breed barriers between some breeds. There is a wide range in the robustness of population definition, from breeds demonstrating high definition to breeds with as little as a third of their genetic variation partitioning into a single population. Utilizing the STRUCTURE algorithm, there was no clear demarcation of the number of population subdivisions; 16 breeds could not be resolved into independent populations, the consequence of outcrossing in established breeds to recently developed breeds with common ancestry. These 16 breeds were divided into 6 populations. Ninety-six percent of cats in a sample set of 1040 were correctly assigned to their classified breed or breed group/population. Average breed STR heterozygosities ranged from moderate (0.53; Havana, Korat) to high (0.85; Norwegian Forest Cat, Manx). Most of the variation in cat breeds was observed within a breed population (83.7%), versus 16.3% of the variation observed between populations. The hierarchical relationships of cat breeds is poorly defined as demonstrated by phylogenetic trees generated from both STR and SNP data, though phylogeographic grouping of breeds derived completely or in part from Southeast Asian ancestors was apparent.

Altitudinal variation in age and body size in Yunnan pond frog (Pelophylax pleuraden).

PubMed

Lou, Shang Ling; Jin, Long; Liu, Yan Hong; Mi, Zhi Ping; Tao, Gang; Tang, Yu Mei; Liao, Wen Bo

2012-08-01

Large-scale systematic patterns of body size are a basic concern of evolutionary biology. Identifying body size variation along altitudinal gradients may help us to understand the evolution of life history of animals. In this study, we investigated altitudinal variation in body size, age and growth rate in Chinese endemic frog, Pelophylax pleuraden. Data sampled from five populations covering an altitudinal span of 1413 to 1935 m in Sichuan province revealed that body size from five populations did not co-vary with altitudes, not following Bergmann's rule. Average adult SVL differed significantly among populations in males, but not in females. For both sexes, average adult age differed significantly among populations. Post-metamorphic growth rate did not co-vary with altitude, and females grew faster than males in all populations. When controlling the effect of age, body size did not differ among populations in both sexes, suggesting that age did not affect variation in body size among populations. For females, there may be other factors, such as the allocation of energy between growth and reproduction, that eliminated the effect of age on body size. To our minds, the major reason of body size variation among populations in male frogs may be related to individual longevity. Our findings also suggest that factors other than age and growth rate may contribute to size differences among populations.

Abundant Gene-by-Environment Interactions in Gene Expression Reaction Norms to Copper within Saccharomyces cerevisiae

PubMed Central

Hodgins-Davis, Andrea; Adomas, Aleksandra B.; Warringer, Jonas; Townsend, Jeffrey P.

2012-01-01

Genetic variation for plastic phenotypes potentially contributes phenotypic variation to populations that can be selected during adaptation to novel ecological contexts. However, the basis and extent of plastic variation that manifests in diverse environments remains elusive. Here, we characterize copper reaction norms for mRNA abundance among five Saccharomyces cerevisiae strains to 1) describe population variation across the full range of ecologically relevant copper concentrations, from starvation to toxicity, and 2) to test the hypothesis that plastic networks exhibit increased population variation for gene expression. We find that although the vast majority of the variation is small in magnitude (considerably <2-fold), not just some, but most genes demonstrate variable expression across environments, across genetic backgrounds, or both. Plastically expressed genes included both genes regulated directly by copper-binding transcription factors Mac1 and Ace1 and genes indirectly responding to the downstream metabolic consequences of the copper gradient, particularly genes involved in copper, iron, and sulfur homeostasis. Copper-regulated gene networks exhibited more similar behavior within the population in environments where those networks have a large impact on fitness. Nevertheless, expression variation in genes like Cup1, important to surviving copper stress, was linked with variation in mitotic fitness and in the breadth of differential expression across the genome. By revealing a broader and deeper range of population variation, our results provide further evidence for the interconnectedness of genome-wide mRNA levels, their dependence on environmental context and genetic background, and the abundance of variation in gene expression that can contribute to future evolution. PMID:23019066

Climate and predation dominate juvenile and adult recruitment in a turtle with temperature-dependent sex determination.

PubMed

Schwanz, Lisa E; Spencer, Ricky-John; Bowden, Rachel M; Janzen, Fredric J

2010-10-01

Conditions experienced early in life can influence phenotypes in ecologically important ways, as exemplified by organisms with environmental sex determination. For organisms with temperature-dependent sex determination (TSD), variation in nest temperatures induces phenotypic variation that could impact population growth rates. In environments that vary over space and time, how does this variation influence key demographic parameters (cohort sex ratio and hatchling recruitment) in early life stages of populations exhibiting TSD? We leverage a 17-year data set on a population of painted turtles, Chrysemys picta, to investigate how spatial variation in nest vegetation cover and temporal variation in climate influence early life-history demography. We found that spatial variation in nest cover strongly influenced nest temperature and sex ratio, but was not correlated with clutch size, nest predation, total nest failure, or hatching success. Temporal variation in climate influenced percentage of total nest failure and cohort sex ratio, but not depredation rate, mean clutch size, or mean hatching success. Total hatchling recruitment in a year was influenced primarily by temporal variation in climate-independent factors, number of nests constructed, and depredation rate. Recruitment of female hatchlings was determined by stochastic variation in nest depredation and annual climate and also by the total nest production. Overall population demography depends more strongly on annual variation in climate and predation than it does on the intricacies of nest-specific biology. Finally, we demonstrate that recruitment of female hatchlings translates into recruitment of breeding females into the population, thus linking climate (and other) effects on early life stages to adult demographics.

Changes in composition of cuticular biochemicals of the facultatively polygynous ant Petalomyrmex phylax during range expansion in Cameroon with respect to social, spatial and genetic variation.

PubMed

Dalecky, Ambroise; Renucci, Marielle; Tirard, Alain; Debout, Gabriel; Roux, Maurice; Kjellberg, Finn; Provost, Erick

2007-09-01

In social insects, biochemicals found at the surface of the cuticle are involved in the recognition process and in protection against desiccation and pathogens. However, the relative contribution of evolutionary forces in shaping diversity of these biochemicals remains largely unresolved in ants. We determined the composition of epicuticular biochemicals for workers sampled in 12 populations of the ant Petalomyrmex phylax from Cameroon. Genetic variation at 12 microsatellite markers was used to infer population history and to provide null expectations under the neutrality hypothesis. Genetic data suggest a recent southward range expansion of this ant species. Furthermore, there is a decline southward in the numbers of queens present in mature colonies. Here, we contrast the pattern of biochemical variation against genetic, social and spatial parameters. We thus provide the first estimates of the relative contribution of neutral and selective processes on variation of ant cuticular profile. Populations in migration-drift disequilibrium showed reduction of within-population variation for genetic markers as well as for cuticular profiles. In these populations, the cuticular profile became biased towards a limited number of high molecular weight molecules. Within- and among-population biochemical variation was explained by both genetic and social variation and by the spatial distribution of populations. We therefore propose that during range expansion of P. phylax, the composition of epicuticular compounds has been affected by a combination of neutral processes - genetic drift and spatially limited dispersal - and spatially varying selection, social organization and environmental effects.

Comparative ecological transcriptomics and the contribution of gene expression to the evolutionary potential of a threatened fish.

PubMed

Brauer, Chris J; Unmack, Peter J; Beheregaray, Luciano B

2017-12-01

Understanding whether small populations with low genetic diversity can respond to rapid environmental change via phenotypic plasticity is an outstanding research question in biology. RNA sequencing (RNA-seq) has recently provided the opportunity to examine variation in gene expression, a surrogate for phenotypic variation, in nonmodel species. We used a comparative RNA-seq approach to assess expression variation within and among adaptively divergent populations of a threatened freshwater fish, Nannoperca australis, found across a steep hydroclimatic gradient in the Murray-Darling Basin, Australia. These populations evolved under contrasting selective environments (e.g., dry/hot lowland; wet/cold upland) and represent opposite ends of the species' spectrum of genetic diversity and population size. We tested the hypothesis that environmental variation among isolated populations has driven the evolution of divergent expression at ecologically important genes using differential expression (DE) analysis and an anova-based comparative phylogenetic expression variance and evolution model framework based on 27,425 de novo assembled transcripts. Additionally, we tested whether gene expression variance within populations was correlated with levels of standing genetic diversity. We identified 290 DE candidate transcripts, 33 transcripts with evidence for high expression plasticity, and 50 candidates for divergent selection on gene expression after accounting for phylogenetic structure. Variance in gene expression appeared unrelated to levels of genetic diversity. Functional annotation of the candidate transcripts revealed that variation in water quality is an important factor influencing expression variation for N. australis. Our findings suggest that gene expression variation can contribute to the evolutionary potential of small populations. © 2017 John Wiley & Sons Ltd.

Population genetic variation in the tree fern Alsophila spinulosa (Cyatheaceae): effects of reproductive strategy.

PubMed

Wang, Ting; Su, Yingjuan; Li, Yuan

2012-01-01

Essentially all ferns can perform both sexual and asexual reproduction. Their populations represent suitable study objects to test the population genetic effects of different reproductive systems. Using the diploid homosporous fern Alsophila spinulosa as an example species, the main purpose of this study was to assess the relative impact of sexual and asexual reproduction on the level and structure of population genetic variation. Inter-simple sequence repeats analysis was conducted on 140 individuals collected from seven populations (HSG, LCH, BPC, MPG, GX, LD, and ZHG) in China. Seventy-four polymorphic bands discriminated a total of 127 multilocus genotypes. Character compatibility analysis revealed that 50.0 to 70.0% of the genotypes had to be deleted in order to obtain a tree-like structure in the data set from populations HSG, LCH, MPG, BPC, GX, and LD; and there was a gradual decrease of conflict in the data set when genotypes with the highest incompatibility counts were successively deleted. In contrast, in population ZHG, only 33.3% of genotypes had to be removed to achieve complete compatibility in the data set, which showed a sharp decline in incompatibility upon the deletion of those genotypes. All populations examined possessed similar levels of genetic variation. Population ZHG was not found to be more differentiated than the other populations. Sexual recombination is the predominant source of genetic variation in most of the examined populations of A. spinulosa. However, somatic mutation contributes most to the genetic variation in population ZHG. This change of the primary mode of reproduction does not cause a significant difference in the population genetic composition. Character compatibility analysis represents an effective approach to separate the role of sexual and asexual components in shaping the genetic pattern of fern populations.

Confidence bounds and hypothesis tests for normal distribution coefficients of variation

Treesearch

Steve P. Verrill; Richard A. Johnson

2007-01-01

For normally distributed populations, we obtain confidence bounds on a ratio of two coefficients of variation, provide a test for the equality of k coefficients of variation, and provide confidence bounds on a coefficient of variation shared by k populations. To develop these confidence bounds and test, we first establish that estimators based on Newton steps from n-...

Short-range phenotypic divergence among genetically distinct parapatric populations of an Australian funnel-web spider.

PubMed

Wong, Mark K L; Woodman, James D; Rowell, David M

2017-07-01

Speciation involves divergence at genetic and phenotypic levels. Where substantial genetic differentiation exists among populations, examining variation in multiple phenotypic characters may elucidate the mechanisms by which divergence and speciation unfold. Previous work on the Australian funnel-web spider Atrax sutherlandi Gray (2010; Records of the Australian Museum 62 , 285-392; Mygalomorphae: Hexathelidae: Atracinae) has revealed a marked genetic structure along a 110-kilometer transect, with six genetically distinct, parapatric populations attributable to past glacial cycles. In the present study, we explore variation in three classes of phenotypic characters (metabolic rate, water loss, and morphological traits) within the context of this phylogeographic structuring. Variation in metabolic and water loss rates shows no detectable association with genetic structure; the little variation observed in these rates may be due to the spiders' behavioral adaptations (i.e., burrowing), which buffer the effects of climatic gradients across the landscape. However, of 17 morphological traits measured, 10 show significant variation among genetic populations, in a disjunct manner that is clearly not latitudinal. Moreover, patterns of variation observed for morphological traits serving different organismic functions (e.g., prey capture, burrowing, and locomotion) are dissimilar. In contrast, a previous study of an ecologically similar sympatric spider with little genetic structure indicated a strong latitudinal response in 10 traits over the same range. The congruence of morphological variation with deep phylogeographic structure in Tallaganda's A. sutherlandi populations, as well as the inconsistent patterns of variation across separate functional traits, suggest that the spiders are likely in early stages of speciation, with parapatric populations independently responding to local selective forces.

Genetic and epigenetic differences associated with environmental gradients in replicate populations of two salt marsh perennials.

PubMed

Foust, C M; Preite, V; Schrey, A W; Alvarez, M; Robertson, M H; Verhoeven, K J F; Richards, C L

2016-04-01

While traits and trait plasticity are partly genetically based, investigating epigenetic mechanisms may provide more nuanced understanding of the mechanisms underlying response to environment. Using AFLP and methylation-sensitive AFLP, we tested the hypothesis that differentiation to habitats along natural salt marsh environmental gradients occurs at epigenetic, but not genetic loci in two salt marsh perennials. We detected significant genetic and epigenetic structure among populations and among subpopulations, but we found multilocus patterns of differentiation to habitat type only in epigenetic variation for both species. In addition, more epigenetic than genetic loci were correlated with habitat in both species. When we analysed genetic and epigenetic variation simultaneously with partial Mantel, we found no correlation between genetic variation and habitat and a significant correlation between epigenetic variation and habitat in Spartina alterniflora. In Borrichia frutescens, we found significant correlations between epigenetic and/or genetic variation and habitat in four of five populations when populations were analysed individually, but there was no significant correlation between genetic or epigenetic variation and habitat when analysed jointly across the five populations. These analyses suggest that epigenetic mechanisms are involved in the response to salt marsh habitats, but also that the relationships among genetic and epigenetic variation and habitat vary by species. Site-specific conditions may also cloud our ability to detect response in replicate populations with similar environmental gradients. Future studies analysing sequence data and the correlation between genetic variation and DNA methylation will be powerful to identify the contributions of genetic and epigenetic response to environmental gradients. © 2016 John Wiley & Sons Ltd.

Quantifying the Variation in the Effective Population Size Within a Genome

PubMed Central

Gossmann, Toni I.; Woolfit, Megan; Eyre-Walker, Adam

2011-01-01

The effective population size (Ne) is one of the most fundamental parameters in population genetics. It is thought to vary across the genome as a consequence of differences in the rate of recombination and the density of selected sites due to the processes of genetic hitchhiking and background selection. Although it is known that there is intragenomic variation in the effective population size in some species, it is not known whether this is widespread or how much variation in the effective population size there is. Here, we test whether the effective population size varies across the genome, between protein-coding genes, in 10 eukaryotic species by considering whether there is significant variation in neutral diversity, taking into account differences in the mutation rate between loci by using the divergence between species. In most species we find significant evidence of variation. We investigate whether the variation in Ne is correlated to recombination rate and the density of selected sites in four species, for which these data are available. We find that Ne is positively correlated to recombination rate in one species, Drosophila melanogaster, and negatively correlated to a measure of the density of selected sites in two others, humans and Arabidopsis thaliana. However, much of the variation remains unexplained. We use a hierarchical Bayesian analysis to quantify the amount of variation in the effective population size and show that it is quite modest in all species—most genes have an Ne that is within a few fold of all other genes. Nonetheless we show that this modest variation in Ne is sufficient to cause significant differences in the efficiency of natural selection across the genome, by demonstrating that the ratio of the number of nonsynonymous to synonymous polymorphisms is significantly correlated to synonymous diversity and estimates of Ne, even taking into account the obvious nonindependence between these measures. PMID:21954163

Variations in pesticide tolerance: Chapter 16

USGS Publications Warehouse

Bridges, Christine M.; Semlitsch, Raymond D.; Lannoo, Michael

2005-01-01

A growing body of evidence suggests that a number of amphibian populations have declined in recent years. The cause of these population declines has been difficult to establish because in some instances only a single species is declining while sympatric species are thriving. This chapter discusses the results of research that has been conducted to determine the degree of variation present in amphibians with respect to their response to insecticide exposure. The study assessed the degree of variation in response to an anthropogenic stressor among and within species of frogs in the family Ranidae, focusing on the variation in tolerance of tadpoles to the insecticide carbaryl. Carbaryl acts by inhibiting nervous system acetylcholinesterase, which is a common mode of action among insecticides; thus, carbaryl can serve as a model chemical with which to examine amphibian responses. The study also analyzed variation in a hierarchical fashion to identify where variation was the greatest: among nine ranid species, among populations within a single species, and within populations of southern leopard frogs.

Resequencing and association analysis of OXTR with autism spectrum disorder in a Japanese population.

PubMed

Egawa, Jun; Watanabe, Yuichiro; Shibuya, Masako; Endo, Taro; Sugimoto, Atsunori; Igeta, Hirofumi; Nunokawa, Ayako; Inoue, Emiko; Someya, Toshiyuki

2015-03-01

The oxytocin receptor (OXTR) is implicated in the pathophysiology of autism spectrum disorder (ASD). A recent study found a rare non-synonymous OXTR gene variation, rs35062132 (R376G), associated with ASD in a Japanese population. In order to investigate the association between rare non-synonymous OXTR variations and ASD, we resequenced OXTR and performed association analysis with ASD in a Japanese population. We resequenced the OXTR coding region in 213 ASD patients. Rare non-synonymous OXTR variations detected by resequencing were genotyped in 213 patients and 667 controls. We detected three rare non-synonymous variations: rs35062132 (R376G/C), rs151257822 (G334D), and g.8809426G>T (R150S). However, there was no significant association between these rare non-synonymous variations and ASD. Our present study does not support the contribution of rare non-synonymous OXTR variations to ASD susceptibility in the Japanese population. © 2014 The Authors. Psychiatry and Clinical Neurosciences © 2014 Japanese Society of Psychiatry and Neurology.

The fall and rise of the Icelandic Arctic fox (Vulpes lagopus): a 50-year demographic study on a non-cyclic Arctic fox population.

PubMed

Unnsteinsdottir, E R; Hersteinsson, P; Pálsson, S; Angerbjörn, A

2016-08-01

In territorial species, observed density dependence is often manifest in lowered reproductive output at high population density where individuals have fewer resources or are forced to inhabit low-quality territories. The Arctic fox (Vulpes lagopus) in Iceland is territorial throughout the year and feeds mostly on birds, since lemmings are absent from the country. Thus, the population does not exhibit short-term population cycles that are evident in most of the species' geographical range. The population has, however, gone through a major long-term fluctuation in population size. Because of the stability in hunting effort and reliable hunting records since 1958, the total number of adult foxes killed annually can be used as an index of population size (N t ). An index of carrying capacity (K) from population growth data for five separate time blocks during 1958-2007 revealed considerable variation in K and allowed a novel definition of population density in terms of K, or N t /K. Correlation analysis suggested that the reproductive rate was largely determined by the proportion of territorial foxes in the population. Variation in litter size and cub mortality was, on the other hand, related to climatic variation. Thus, Arctic foxes in Iceland engage in typical contest competition but can adapt their territory sizes in response to both temporal and spatial variation in carrying capacity, resulting in surprisingly little variation in litter size.

Environmental Variables Explain Genetic Structure in a Beetle-Associated Nematode

PubMed Central

McGaughran, Angela; Morgan, Katy; Sommer, Ralf J.

2014-01-01

The distribution of a species is a complex expression of its ecological and evolutionary history and integrating population genetic, environmental, and ecological data can provide new insights into the effects of the environment on the population structure of species. Previous work demonstrated strong patterns of genetic differentiation in natural populations of the hermaphroditic nematode Pristionchus pacificus in its La Réunion Island habitat, but gave no clear understanding of the role of the environment in structuring this variation. Here, we present what is to our knowledge the first study to statistically evaluate the role of the environment in shaping the structure and distribution of nematode populations. We test the hypothesis that genetic structure in P. pacificus is influenced by environmental variables, by combining population genetic analyses of microsatellite data from 18 populations and 370 strains, with multivariate statistics on environmental data, and species distribution modelling. We assess and quantify the relative importance of environmental factors (geographic distance, altitude, temperature, precipitation, and beetle host) on genetic variation among populations. Despite the fact that geographic populations of P. pacificus comprise vast genetic diversity sourced from multiple ancestral lineages, we find strong evidence for local associations between environment and genetic variation. Further, we show that significantly more genetic variation in P. pacificus populations is explained by environmental variation than by geographic distances. This supports a strong role for environmental heterogeneity vs. genetic drift in the divergence of populations, which we suggest may be influenced by adaptive forces. PMID:24498073

Plant Chemistry and Local Adaptation of a Specialized Folivore

PubMed Central

Laukkanen, Liisa; Leimu, Roosa; Muola, Anne; Lilley, Marianna; Salminen, Juha-Pekka; Mutikainen, Pia

2012-01-01

Local adaptation is central for creating and maintaining spatial variation in plant-herbivore interactions. Short-lived insect herbivores feeding on long-lived plants are likely to adapt to their local host plants, because of their short generation time, poor dispersal, and geographically varying selection due to variation in plant defences. In a reciprocal feeding trial, we investigated the impact of geographic variation in plant secondary chemistry of a long-lived plant, Vincetoxicum hirundinaria, on among-population variation in local adaptation of a specialist leaf-feeding herbivore, Abrostola asclepiadis. The occurrence and degree of local adaptation varied among populations. This variation correlated with qualitative and quantitative differences in plant chemistry among the plant populations. These findings provide insights into the mechanisms driving variation in local adaptation in this specialized plant-herbivore interaction. PMID:22666493

Achieving polio eradication: a review of health communication evidence and lessons learned in India and Pakistan

PubMed Central

Chitnis, Ketan; Morry, Chris; Feek, Warren; Bates, Jeffrey; Galway, Michael; Ogden, Ellyn

2009-01-01

Abstract Since 1988, the world has come very close to eradicating polio through the Global Polio Eradication Initiative, in which communication interventions have played a consistently central role. Mass media and information dissemination approaches used in immunization efforts worldwide have contributed to this success. However, reaching the hardest-to-reach, the poorest, the most marginalized and those without access to health services has been challenging. In the last push to eradicate polio, Polio Eradication Initiative communication strategies have become increasingly research-driven and innovative, particularly through the introduction of sustained interpersonal communication and social mobilization approaches to reach unreached populations. This review examines polio communication efforts in India and Pakistan between the years 2000 and 2007. It shows how epidemiological, social and behavioural data guide communication strategies that have contributed to increased levels of polio immunity, particularly among underserved and hard-to-reach populations. It illustrates how evidence-based and planned communication strategies – such as sustained media campaigns, intensive community and social mobilization, interpersonal communication and political and national advocacy combined – have contributed to reducing polio incidence in these countries. Findings show that communication strategies have contributed on several levels by: mobilizing social networks and leaders; creating political will; increasing knowledge; ensuring individual and community-level demand; overcoming gender barriers and resistance to vaccination; and reaching out to the poorest and marginalized populations. The review concludes with observations about the added value of communication strategies in polio eradication efforts and implications for global and local public health communication interventions. PMID:19705014

Achieving polio eradication: a review of health communication evidence and lessons learned in India and Pakistan.

PubMed

Obregón, Rafael; Chitnis, Ketan; Morry, Chris; Feek, Warren; Bates, Jeffrey; Galway, Michael; Ogden, Ellyn

2009-08-01

Since 1988, the world has come very close to eradicating polio through the Global Polio Eradication Initiative, in which communication interventions have played a consistently central role. Mass media and information dissemination approaches used in immunization efforts worldwide have contributed to this success. However, reaching the hardest-to-reach, the poorest, the most marginalized and those without access to health services has been challenging. In the last push to eradicate polio, Polio Eradication Initiative communication strategies have become increasingly research-driven and innovative, particularly through the introduction of sustained interpersonal communication and social mobilization approaches to reach unreached populations. This review examines polio communication efforts in India and Pakistan between the years 2000 and 2007. It shows how epidemiological, social and behavioural data guide communication strategies that have contributed to increased levels of polio immunity, particularly among underserved and hard-to-reach populations. It illustrates how evidence-based and planned communication strategies - such as sustained media campaigns, intensive community and social mobilization, interpersonal communication and political and national advocacy combined - have contributed to reducing polio incidence in these countries. Findings show that communication strategies have contributed on several levels by: mobilizing social networks and leaders; creating political will; increasing knowledge; ensuring individual and community-level demand; overcoming gender barriers and resistance to vaccination; and reaching out to the poorest and marginalized populations. The review concludes with observations about the added value of communication strategies in polio eradication efforts and implications for global and local public health communication interventions.

Scanning electron microscopy analysis of hair index on Karachi's population for social and professional appearance enhancement.

PubMed

Ali, N; Zohra, R R; Qader, S A U; Mumtaz, M

2015-06-01

Hair texture, appearance and pigment play an important role in social and professional communication and maintaining an overall appearance. This study was especially designed for morphological assessment of hair damage caused to Karachi's population due to natural factors and cosmetic treatments using scanning electron microscopy (SEM) technique. Hair samples under the study of synthetic factor's effect were given several cosmetic treatments (hot straightened, bleached, synthetic dyed and henna dyed) whereas samples under natural factor's effect (variation in gender, age and pigmentation) were left untreated. Morphological assessment was performed using SEM technique. Results obtained were statistically analysed using minitab 16 and spss 18 softwares. Scanning electron microscopy images revealed less number of cuticular scales in males than females of same age although size of cuticular scales was found to be larger in males than in females. Mean hair index of white hair was greater than black hair of the same head as it is comparatively newly originated. Tukey's method revealed that among cosmetic treatments, bleaching and synthetic henna caused most of the damage to the hair. Statistical evaluation of results obtained from SEM analysis revealed that human scalp hair index show morphological variation with respect to age, gender, hair pigmentation, chemical and physical treatments. Individuals opting for cosmetic treatments could clearly visualize the extent of hair damage these may cause in long run. © 2015 Society of Cosmetic Scientists and the Société Française de Cosmétologie.

Electronic communication preferences among mothers in the neonatal intensive care unit.

PubMed

Weems, M F; Graetz, I; Lan, R; DeBaer, L R; Beeman, G

2016-11-01

Mobile communication with the medical-care team has the potential to decrease stress among parents of infants admitted to the neonatal intensive care unit (NICU). We assessed mobile use and communication preferences in a population of urban minority NICU mothers. A 30-question English language survey was administered to mothers of NICU patients. The survey was completed by 217 mothers, 75% were Black, and 75% reported annual household income below $20 000. Only 56% had a computer with Internet access at home, but 79% used smartphones. Most (79%) have searched the Internet for health information in the past year. Receiving electronic messages about their babies was viewed favorably, and text messaging was the preferred platform. The majority of mothers felt electronic messaging would improve communication but should not replace verbal communication. Mobile communication is used widely in this population of NICU mothers and could potentially improve provider-parent communication and reduce parental stress.

Communication and marketing as climate change-intervention assets a public health perspective.

PubMed

Maibach, Edward W; Roser-Renouf, Connie; Leiserowitz, Anthony

2008-11-01

The understanding that global climate change represents a profound threat to the health and well-being of human and nonhuman species worldwide is growing. This article examines the potential of communication and marketing interventions to influence population behavior in ways consistent with climate change prevention and adaptation objectives. Specifically, using a framework based on an ecologic model of public health, the paper examines: (1) the potential of communication and marketing interventions to influence population behaviors of concern, including support for appropriate public policies; (2) potential target audiences for such programs; and (3) the attributes of effective climate change messages. Communication and marketing interventions appear to have considerable potential to promote important population behavior change objectives, but there is an urgent need for additional translational research to effectively harvest this potential to combat climate change.

Spatiotemporal variation in survival rates: implications for population dynamics of yellow-bellied marmots.

PubMed

Ozgul, Arpat; Armitage, Kenneth B; Blumstein, Daniel T; Oli, Madan K

2006-04-01

Spatiotemporal variation in age-specific survival rates can profoundly influence population dynamics, but few studies of vertebrates have thoroughly investigated both spatial and temporal variability in age-specific survival rates. We used 28 years (1976-2003) of capture-mark-recapture (CMR) data from 17 locations to parameterize an age-structured Cormack-Jolly-Seber model, and investigated spatial and temporal variation in age-specific annual survival rates of yellow-bellied marmots (Marmota flaviventris). Survival rates varied both spatially and temporally, with survival of younger animals exhibiting the highest degree of variation. Juvenile survival rates varied from 0.52 +/- 0.05 to 0.78 +/- 0.10 among sites and from 0.15 +/- 0.14 to 0.89 +/- 0.06 over time. Adult survival rates varied from 0.62 +/- 0.09 to 0.80 +/- 0.03 among sites, but did not vary significantly over time. We used reverse-time CMR models to estimate the realized population growth rate (lamda), and to investigate the influence of the observed variation in age-specific survival rates on lamda. The realized growth rate of the population closely covaried with, and was significantly influenced by, spatiotemporal variation in juvenile survival rate. High variability in juvenile survival rates over space and time clearly influenced the dynamics of our study population and is also likely to be an important determinant of the spatiotemporal variation in the population dynamics of other mammals with similar life history characteristics.

Meiotic gene-conversion rate and tract length variation in the human genome.

PubMed

Padhukasahasram, Badri; Rannala, Bruce

2013-02-27

Meiotic recombination occurs in the form of two different mechanisms called crossing-over and gene-conversion and both processes have an important role in shaping genetic variation in populations. Although variation in crossing-over rates has been studied extensively using sperm-typing experiments, pedigree studies and population genetic approaches, our knowledge of variation in gene-conversion parameters (ie, rates and mean tract lengths) remains far from complete. To explore variability in population gene-conversion rates and its relationship to crossing-over rate variation patterns, we have developed and validated using coalescent simulations a comprehensive Bayesian full-likelihood method that can jointly infer crossing-over and gene-conversion rates as well as tract lengths from population genomic data under general variable rate models with recombination hotspots. Here, we apply this new method to SNP data from multiple human populations and attempt to characterize for the first time the fine-scale variation in gene-conversion parameters along the human genome. We find that the estimated ratio of gene-conversion to crossing-over rates varies considerably across genomic regions as well as between populations. However, there is a great degree of uncertainty associated with such estimates. We also find substantial evidence for variation in the mean conversion tract length. The estimated tract lengths did not show any negative relationship with the local heterozygosity levels in our analysis.European Journal of Human Genetics advance online publication, 27 February 2013; doi:10.1038/ejhg.2013.30.

Molecular Population Genetics

PubMed Central

Casillas, Sònia; Barbadilla, Antonio

2017-01-01

Molecular population genetics aims to explain genetic variation and molecular evolution from population genetics principles. The field was born 50 years ago with the first measures of genetic variation in allozyme loci, continued with the nucleotide sequencing era, and is currently in the era of population genomics. During this period, molecular population genetics has been revolutionized by progress in data acquisition and theoretical developments. The conceptual elegance of the neutral theory of molecular evolution or the footprint carved by natural selection on the patterns of genetic variation are two examples of the vast number of inspiring findings of population genetics research. Since the inception of the field, Drosophila has been the prominent model species: molecular variation in populations was first described in Drosophila and most of the population genetics hypotheses were tested in Drosophila species. In this review, we describe the main concepts, methods, and landmarks of molecular population genetics, using the Drosophila model as a reference. We describe the different genetic data sets made available by advances in molecular technologies, and the theoretical developments fostered by these data. Finally, we review the results and new insights provided by the population genomics approach, and conclude by enumerating challenges and new lines of inquiry posed by increasingly large population scale sequence data. PMID:28270526

Molecular Population Genetics.

PubMed

Casillas, Sònia; Barbadilla, Antonio

2017-03-01

Molecular population genetics aims to explain genetic variation and molecular evolution from population genetics principles. The field was born 50 years ago with the first measures of genetic variation in allozyme loci, continued with the nucleotide sequencing era, and is currently in the era of population genomics. During this period, molecular population genetics has been revolutionized by progress in data acquisition and theoretical developments. The conceptual elegance of the neutral theory of molecular evolution or the footprint carved by natural selection on the patterns of genetic variation are two examples of the vast number of inspiring findings of population genetics research. Since the inception of the field, Drosophila has been the prominent model species: molecular variation in populations was first described in Drosophila and most of the population genetics hypotheses were tested in Drosophila species. In this review, we describe the main concepts, methods, and landmarks of molecular population genetics, using the Drosophila model as a reference. We describe the different genetic data sets made available by advances in molecular technologies, and the theoretical developments fostered by these data. Finally, we review the results and new insights provided by the population genomics approach, and conclude by enumerating challenges and new lines of inquiry posed by increasingly large population scale sequence data. Copyright © 2017 Casillas and Barbadilla.

Mitochondrial DNA haplogroup variation of contemporary mixed South Americans reveals prehistoric displacements linked to archaeologically-derived culture history.

PubMed

Rothhammer, Francisco; Fehren-Schmitz, Lars; Puddu, Giannina; Capriles, José

2017-11-01

The purpose of this study was to examine South American population structure and prehistoric population displacements prior to the Spanish conquest, utilizing mitochondrial DNA haplogroups of extant mixed populations from Mexico, Costa Rica, Venezuela, Colombia, Ecuador, Peru, Bolivia, Brazil, Argentina, and Chile. Relative frequencies of four pan-American haplogroups, obtained from published databases, were analyzed to evaluate patterns of variations, population structure and possible prehistoric migration pathways. Patterns of mtDNA variation verify biogeographic drift processes and possible migratory pathways. We propose an updated model of South American colonization that is fully compatible with previous studies based on autosomal, mtDNA, and Y chromosome variation and with archaeologically-derived culture history. © 2017 Wiley Periodicals, Inc.

Predictors of Satisfaction With Doctor and Nurse Communication: A National Study.

PubMed

McFarland, Daniel C; Johnson Shen, Megan; Holcombe, Randall F

2017-10-01

Prior research indicates that effective communication between medical providers and patients is associated with a number of positive patient outcomes, yet little research has examined how ecological factors (e.g., hospital size, local demographics) influence patients' reported satisfaction with doctor and nurse communication. Given the current emphasis on improving patient satisfaction in hospitals across the United States, understanding these factors is critical to interpreting patient satisfaction and improving patient-centered communication, particularly in diverse and dense populations. As such, this study examined county-level data including population density, population diversity, and hospital structural factors as predictors of patient satisfaction with doctor and nurse communication. Hospital Consumer Assessment of Healthcare Providers and Systems (HCAHPS), U.S. Census data, and number of hospital beds were obtained from publicly available Hospital Compare, U.S. Census, and American Hospital Directory websites, respectively. Multivariate regression modeling was performed for the individual dimensions of HCAHPS scores assessing doctor and nurse communication. Standardized partial regression coefficients were used to assess strengths of county-level predictors. County-level factors accounted for 30% and 16% of variability in patient satisfaction with doctor and nurse communication, respectively. College education (β = 0.45) and White ethnicity (β = 0.25) most strongly predicted a favorable rating of doctor and nurse communication, respectively. Primary language (non-English speaking; β = -0.50) most strongly predicted an unfavorable rating of doctor communication, while number of hospital beds (β = -0.16) and foreign-born (β = -0.16) most strongly predicted an unfavorable rating of nurse communication. County-level predictors should be considered when interpreting patient satisfaction with doctor and nurse communication and designing multilevel patient-centered communication improvement strategies. Discordant findings with individual-level factors should be explored further.

Genetic variation among interconnected populations of Catostomus occidentalis: Implications for distinguishing impacts of contaminants from biogeographical structuring

USGS Publications Warehouse

Whitehead, A.; Anderson, S.L.; Kuivila, K.M.; Roach, J.L.; May, B.

2003-01-01

Exposure to contaminants can affect survivorship, recruitment, reproductive success, mutation rates and migration, and may play a significant role in the partitioning of genetic variation among exposed and nonexposed populations. However, the application of molecular population genetic data to evaluate such influences has been uncommon and often flawed. We tested whether patterns of genetic variation among native fish populations (Sacramento sucker, Catostomus occidentalis) in the Central Valley of California were consistent with long-term pesticide exposure history, or primarily with expectations based on biogeography. Field sampling was designed to rigorously test for both geographical and contamination influences. Fine-scale structure of these interconnected populations was detected with both amplified fragment length polymorphisms (AFLP) and microsatellite markers, and patterns of variation elucidated by the two marker systems were highly concordant. Analyses indicated that biogeographical hypotheses described the data set better than hypotheses relating to common historical pesticide exposure. Downstream populations had higher genetic diversity than upstream populations, regardless of exposure history, and genetic distances showed that populations from the same river system tended to cluster together. Relatedness among populations reflected primarily directions of gene flow, rather than convergence among contaminant-exposed populations. Watershed geography accounted for significant partitioning of genetic variation among populations, whereas contaminant exposure history did not. Genetic patterns indicating contaminant-induced selection, increased mutation rates or recent bottlenecks were weak or absent. We stress the importance of testing contaminant-induced genetic change hypotheses within a biogeographical context. Strategic application of molecular markers for analysis of fine-scale structure, and for evaluating contaminant impacts on gene pools, is discussed.

Body size and allometric shape variation in the molly Poecilia vivipara along a gradient of salinity and predation.

PubMed

Araújo, Márcio S; Perez, S Ivan; Magazoni, Maria Julia C; Petry, Ana C

2014-12-04

Phenotypic diversity among populations may result from divergent natural selection acting directly on traits or via correlated responses to changes in other traits. One of the most frequent patterns of correlated response is the proportional change in the dimensions of anatomical traits associated with changes in growth or absolute size, known as allometry. Livebearing fishes subject to predation gradients have been shown to repeatedly evolve larger caudal peduncles and smaller cranial regions under high predation regimes. Poecilia vivipara is a livebearing fish commonly found in coastal lagoons in the north of the state of Rio de Janeiro, Brazil. Similar to what is observed in other predation gradients, lagoons inhabited by P. vivipara vary in the presence of piscivorous fishes; contrary to other poeciliid systems, populations of P. vivipara vary greatly in body size, which opens the possibility of strong allometric effects on shape variation. Here we investigated body shape diversification among six populations of P. vivipara along a predation gradient and its relationship with allometric trajectories within and among populations. We found substantial body size variation and correlated shape changes among populations. Multivariate regression analysis showed that size variation among populations accounted for 66% of shape variation in females and 38% in males, suggesting that size is the most important dimension underlying shape variation among populations of P. vivipara in this system. Changes in the relative sizes of the caudal peduncle and cranial regions were only partly in line with predictions from divergent natural selection associated with predation regime. Our results suggest the possibility that adaptive shape variation among populations has been partly constrained by allometry in P. vivipara. Processes governing body size changes are therefore important in the diversification of this species. We conclude that in species characterized by substantial among-population differences in body size, ignoring allometric effects when investigating divergent natural selection's role in phenotypic diversification might not be warranted.

Weevil x Insecticide: Does 'Personality' Matter?

PubMed

Morales, Juliana A; Cardoso, Danúbia G; Della Lucia, Terezinha Maria C; Guedes, Raul Narciso C

2013-01-01

An insect's behavior is the expression of its integrated physiology in response to external and internal stimuli, turning insect behavior into a potential determinant of insecticide exposure. Behavioral traits may therefore influence insecticide efficacy against insects, compromising the validity of standard bioassays of insecticide activity, which are fundamentally based on lethality alone. By extension, insect 'personality' (i.e., an individual's integrated set of behavioral tendencies that is inferred from multiple empirical measures) may also be an important determinant of insecticide exposure and activity. This has yet to be considered because the behavioral studies involving insects and insecticides focus on populations rather than on individuals. Even among studies of animal 'personality', the relative contributions of individual and population variation are usually neglected. Here, we assessed behavioral traits (within the categories: activity, boldness/shyness, and exploration/avoidance) of individuals from 15 populations of the maize weevil (Sitophilus zeamais), an important stored-grain pest with serious problems of insecticide resistance, and correlated the behavioral responses with the activity of the insecticide deltamethrin. This analysis was performed at both the population and individual levels. There was significant variation in weevil 'personality' among individuals and populations, but variation among individuals within populations accounted for most of the observed variation (92.57%). This result emphasizes the importance of individual variation in behavioral and 'personality' studies. When the behavioral traits assessed were correlated with median lethal time (LT50) at the population level and with the survival time under insecticide exposure, activity traits, particularly the distance walked, significantly increased survival time. Therefore, behavioral traits are important components of insecticide efficacy, and individual variation should be considered in such studies. This is so because population differences provided only crude approximation of the individual personality in a restrained experimental setting likely to restrict individual behavior favoring the transposition of the individual variation to the population.

Toll-like receptor variation in the bottlenecked population of the Seychelles warbler: computer simulations see the 'ghost of selection past' and quantify the 'drift debt'.

PubMed

Gilroy, D L; Phillips, K P; Richardson, D S; van Oosterhout, C

2017-07-01

Balancing selection can maintain immunogenetic variation within host populations, but detecting its signal in a postbottlenecked population is challenging due to the potentially overriding effects of drift. Toll-like receptor genes (TLRs) play a fundamental role in vertebrate immune defence and are predicted to be under balancing selection. We previously characterized variation at TLR loci in the Seychelles warbler (Acrocephalus sechellensis), an endemic passerine that has undergone a historical bottleneck. Five of seven TLR loci were polymorphic, which is in sharp contrast to the low genomewide variation observed. However, standard population genetic statistical methods failed to detect a contemporary signature of selection at any TLR locus. We examined whether the observed TLR polymorphism could be explained by neutral evolution, simulating the population's demography in the software DIYABC. This showed that the posterior distributions of mutation rates had to be unrealistically high to explain the observed genetic variation. We then conducted simulations with an agent-based model using typical values for the mutation rate, which indicated that weak balancing selection has acted on the three TLR genes. The model was able to detect evidence of past selection elevating TLR polymorphism in the prebottleneck populations, but was unable to discern any effects of balancing selection in the contemporary population. Our results show drift is the overriding evolutionary force that has shaped TLR variation in the contemporary Seychelles warbler population, and the observed TLR polymorphisms might be merely the 'ghost of selection past'. Forecast models predict immunogenetic variation in this species will continue to be eroded in the absence of contemporary balancing selection. Such 'drift debt' occurs when a gene pool has not yet reached its new equilibrium level of polymorphism, and this loss could be an important threat to many recently bottlenecked populations. © 2017 European Society For Evolutionary Biology. Journal of Evolutionary Biology © 2017 European Society For Evolutionary Biology.

Misreading Science in the Twentieth Century.

ERIC Educational Resources Information Center

Budd, John M.

2001-01-01

Considers textual aspects of scientific communication and problems for reception presented by the complex dynamics of communicating scientific work. Discusses scientific work based on fraud or misconduct and disputes about the nature of science, and applies reception theory and reader-response criticism to understand variations in readings of the…

Analysis on design and optimization of dispersion-managed communication systems

NASA Astrophysics Data System (ADS)

El-Aasser, Mostafa A.; Dua, Puneit; Dutta, Niloy K.

2002-07-01

The variational method is a useful tool that can be used for design and optimization of dispersion-managed communication systems. Using this powerful tool, we evaluate the characteristics of a carrier signal for certain system parameters and describe several features of a dispersion-managed soliton.

DNA methylation-based variation between human populations.

PubMed

Kader, Farzeen; Ghai, Meenu

2017-02-01

Several studies have proved that DNA methylation affects regulation of gene expression and development. Epigenome-wide studies have reported variation in methylation patterns between populations, including Caucasians, non-Caucasians (Blacks), Hispanics, Arabs, and numerous populations of the African continent. Not only has DNA methylation differences shown to impact externally visible characteristics, but is also a potential biomarker for underlying racial health disparities between human populations. Ethnicity-related methylation differences set their mark during early embryonic development. Genetic variations, such as single-nucleotide polymorphisms and environmental factors, such as age, dietary folate, socioeconomic status, and smoking, impacts DNA methylation levels, which reciprocally impacts expression of phenotypes. Studies show that it is necessary to address these external influences when attempting to differentiate between populations since the relative impacts of these factors on the human methylome remain uncertain. The present review summarises several reported attempts to establish the contribution of differential DNA methylation to natural human variation, and shows that DNA methylation could represent new opportunities for risk stratification and prevention of several diseases amongst populations world-wide. Variation of methylation patterns between human populations is an exciting prospect which inspires further valuable research to apply the concept in routine medical and forensic casework. However, trans-generational inheritance needs to be quantified to decipher the proportion of variation contributed by DNA methylation. The future holds thorough evaluation of the epigenome to understand quantification, heritability, and the effect of DNA methylation on phenotypes. In addition, methylation profiling of the same ethnic groups across geographical locations will shed light on conserved methylation differences in populations.

Testing a key assumption in animal communication: between-individual variation in female visual systems alters perception of male signals

PubMed Central

Ensminger, Amanda L.; Shawkey, Matthew D.; Lucas, Jeffrey R.; Fernández-Juricic, Esteban

2017-01-01

ABSTRACT Variation in male signal production has been extensively studied because of its relevance to animal communication and sexual selection. Although we now know much about the mechanisms that can lead to variation between males in the properties of their signals, there is still a general assumption that there is little variation in terms of how females process these male signals. Variation between females in signal processing may lead to variation between females in how they rank individual males, meaning that one single signal may not be universally attractive to all females. We tested this assumption in a group of female wild-caught brown-headed cowbirds (Molothrus ater), a species that uses a male visual signal (e.g. a wingspread display) to make its mate-choice decisions. We found that females varied in two key parameters of their visual sensory systems related to chromatic and achromatic vision: cone densities (both total and proportions) and cone oil droplet absorbance. Using visual chromatic and achromatic contrast modeling, we then found that this between-individual variation in visual physiology leads to significant between-individual differences in how females perceive chromatic and achromatic male signals. These differences may lead to variation in female preferences for male visual signals, which would provide a potential mechanism for explaining individual differences in mate-choice behavior. PMID:29247048

Testing a key assumption in animal communication: between-individual variation in female visual systems alters perception of male signals.

PubMed

Ronald, Kelly L; Ensminger, Amanda L; Shawkey, Matthew D; Lucas, Jeffrey R; Fernández-Juricic, Esteban

2017-12-15

Variation in male signal production has been extensively studied because of its relevance to animal communication and sexual selection. Although we now know much about the mechanisms that can lead to variation between males in the properties of their signals, there is still a general assumption that there is little variation in terms of how females process these male signals. Variation between females in signal processing may lead to variation between females in how they rank individual males, meaning that one single signal may not be universally attractive to all females. We tested this assumption in a group of female wild-caught brown-headed cowbirds ( Molothrus ater ), a species that uses a male visual signal (e.g. a wingspread display) to make its mate-choice decisions. We found that females varied in two key parameters of their visual sensory systems related to chromatic and achromatic vision: cone densities (both total and proportions) and cone oil droplet absorbance. Using visual chromatic and achromatic contrast modeling, we then found that this between-individual variation in visual physiology leads to significant between-individual differences in how females perceive chromatic and achromatic male signals. These differences may lead to variation in female preferences for male visual signals, which would provide a potential mechanism for explaining individual differences in mate-choice behavior. © 2017. Published by The Company of Biologists Ltd.

The Role of Communications in Population and Family Planning Programs.

ERIC Educational Resources Information Center

Sweeney, William O.

In this paper, the author outlines the historical development of information and education programs for population control and family planning, arguing that communications activities should receive as much emphasis as the health services program. The public information aspect includes use of mass media, advertising and promotion, public relations…

Native South American genetic structure and prehistory inferred from hierarchical modeling of mtDNA.

PubMed

Lewis, Cecil M; Long, Jeffrey C

2008-03-01

Genetic diversity in Native South Americans forms a complex pattern at both the continental and local levels. In comparing the West to the East, there is more variation within groups and smaller genetic distances between groups. From this pattern, researchers have proposed that there is more variation in the West and that a larger, more genetically diverse, founding population entered the West than the East. Here, we question this characterization of South American genetic variation and its interpretation. Our concern arises because others have inferred regional variation from the mean variation within local populations without taking into account the variation among local populations within the same region. This failure produces a biased view of the actual variation in the East. In this study, we analyze the mitochondrial DNA sequence between positions 16040 and 16322 of the Cambridge reference sequence. Our sample represents a total of 886 people from 27 indigenous populations from South (22), Central (3), and North America (2). The basic unit of our analyses is nucleotide identity by descent, which is easily modeled and proportional to nucleotide diversity. We use a forward modeling strategy to fit a series of nested models to identity by descent within and between all pairs of local populations. This method provides estimates of identity by descent at different levels of population hierarchy without assuming homogeneity within populations, regions, or continents. Our main discovery is that Eastern South America harbors more genetic variation than has been recognized. We find no evidence that there is increased identity by descent in the East relative to the total for South America. By contrast, we discovered that populations in the Western region, as a group, harbor more identity by descent than has been previously recognized, despite the fact that average identity by descent within groups is lower. In this light, there is no need to postulate separate founding populations for the East and the West because the variability in the East could serve as a source for the Western gene pools.

Length Variation of Cag/Caa Trinucleotide Repeats in Natural Populations of Drosophila Melanogaster and Its Relation to the Recombination Rate

PubMed Central

Michalakis, Y.; Veuille, M.

1996-01-01

Eleven genes distributed along the Drosophila melanogaster chromosome 2 and showing exonic tandem repeats of glutamine codons (CAG or CAA) were surveyed for length variation in a sample of four European and African populations. Only one gene was monomorphic. Eight genes were polymorphic in all populations, with a total number of alleles varying between five and 12 for 120 chromosomes. The average heterozygozity per locus and population was 0.41. Selective neutrality in length variation could not be rejected under the assumptions of the infinite allele model. Significant population subdivision was found though no geographical pattern emerged, all populations being equally different. Significant linkage disequilibrium was found in four out of seven cases where the genetic distance between loci was <1 cM and was negligible when the distance was larger. There is evidence that these associations were established after the populations separated. An unexpected result was that variation at each locus was independent of the coefficient of exchange, although the latter ranged from zero to the relatively high value of 6.7%. This would indicate that background selection and selective hitchhiking, which are thought to affect levels of nucleotide substitution polymorphism, have no effect on trinucleotide repeat variation. PMID:8844158

Rare variation facilitates inferences of fine-scale population structure in humans.

PubMed

O'Connor, Timothy D; Fu, Wenqing; Mychaleckyj, Josyf C; Logsdon, Benjamin; Auer, Paul; Carlson, Christopher S; Leal, Suzanne M; Smith, Joshua D; Rieder, Mark J; Bamshad, Michael J; Nickerson, Deborah A; Akey, Joshua M

2015-03-01

Understanding the genetic structure of human populations has important implications for the design and interpretation of disease mapping studies and reconstructing human evolutionary history. To date, inferences of human population structure have primarily been made with common variants. However, recent large-scale resequencing studies have shown an abundance of rare variation in humans, which may be particularly useful for making inferences of fine-scale population structure. To this end, we used an information theory framework and extensive coalescent simulations to rigorously quantify the informativeness of rare and common variation to detect signatures of fine-scale population structure. We show that rare variation affords unique insights into patterns of recent population structure. Furthermore, to empirically assess our theoretical findings, we analyzed high-coverage exome sequences in 6,515 European and African American individuals. As predicted, rare variants are more informative than common polymorphisms in revealing a distinct cluster of European-American individuals, and subsequent analyses demonstrate that these individuals are likely of Ashkenazi Jewish ancestry. Our results provide new insights into the population structure using rare variation, which will be an important factor to account for in rare variant association studies. © The Author 2014. Published by Oxford University Press on behalf of the Society for Molecular Biology and Evolution.

Snail phenotypic variation and stress proteins: do different heat response strategies contribute to Waddington's widget in field populations?

PubMed

Köhler, Heinz-R; Lazzara, Raimondo; Dittbrenner, Nils; Capowiez, Yvan; Mazzia, Christophe; Triebskorn, Rita

2009-03-15

On the basis of studies with laboratory strains of Drosophila and Arabidopsis, it has been hypothesized that potential buffers to the expression of phenotypic morphological variation, such as Hsp90 and possibly Hsp70, represent important components of Waddington's widget, which may confer capacitive evolution. As studies on field populations of living organisms to test this hypothesis are lacking, we tested whether a heat response strategy involving high stress protein levels is associated with low morphological variation and vice versa, using four natural populations of Mediterranean pulmonate snails. In response to 8 hr of elevated temperatures, a population of Xeropicta derbentina with uniform shell pigmentation pattern showed remarkably high Hsp70 but low Hsp90 levels. In contrast, a highly variable population of Cernuella virgata kept both Hsp90 and Hsp70 levels low when held at diverse though environmentally relevant temperatures. Two other populations (Theba pisana and another X. derbentina population) with intermediate variation in shell pigmentation pattern were also intermediate in inducing Hsp70, though Hsp90 was maintained at a low level. The observed correlation of stress protein levels and coloration pattern variation provide the first indirect evidence for an association of stress proteins with Waddington's widget under natural conditions.

Conservation genetics of bull trout: Geographic distribution of variation at microsatellite loci.

Treesearch

P. Spruell; A.R. Hemmingsen; P.J. Howell; N. Kanda; F.W. Allendorf

2003-01-01

We describe the genetic population structure of 65 bull trout (Salvelinus confluentus) populations from the northwestern United States using four microsatellite loci. The distribution of genetic variation as measured by microsatellites is consistent with previous allozyme and mitochondrial DNA analysis. There is relatively little genetic variation...

Interventions to improve communication between people with dementia and nursing staff during daily nursing care: A systematic review.

PubMed

Machiels, Mariska; Metzelthin, Silke F; Hamers, Jan P H; Zwakhalen, Sandra M G

2017-01-01

To provide adequate nursing care it is important for nursing staff to communicate effectively with people with dementia. Due to their limited communication skills, people with dementia have difficulties in understanding communication and expressing themselves verbally. Nursing staff members often report communication difficulties with people with dementia, which emphasises the urgent need for interventions to improve their communication with people in this specific target group. To provide an up-to-date overview of communication interventions that are applicable during daily nursing care activities, irrespective of care setting, and to describe the effects on communication outcomes in people with dementia and nursing staff. Systematic literature review DATA SOURCES: The Cochrane Library, CINAHL, PsycINFO, and Pubmed databases were searched for all articles published until the 23rd of February 2016. Papers were included, if: (1) interventions focused on communication between nursing staff and people with dementia and were applicable during daily nursing care; (2) studies were (randomised) controlled trials; (3) papers were written in English, Dutch, or German. Data were extracted on content and communication outcomes of interventions, and on methodological quality of the studies. The data extraction form and methodological quality checklist were based on the Method Guidelines for Systematic Reviews for the Cochrane Back Review Group. Six studies on communication interventions were included. All of the studies incorporated a communication skills training for nursing staff with a broad range in frequency, duration and content. In addition, there was wide variation in the communication outcome measures used. Four studies measured non-verbal communication, all found positive effects on at least some of the communication outcomes. Four studies measured verbal communication, of which three found positive effects on at least one of the measured outcomes. Methodological quality assessment demonstrated a high risk of bias in five of the six studies. Few studies have been identified with wide variation in interventions and outcome measures. In addition, the methodological shortcomings make it difficult, to draw conclusions about the effectiveness. More research is needed to develop and evaluate communication interventions. Additionally, it is useful to reach consensus on defining and measuring communication. Copyright © 2017 Elsevier Ltd. All rights reserved.

Combining animal personalities with transcriptomics resolves individual variation within a wild-type zebrafish population and identifies underpinning molecular differences in brain function.

PubMed

Rey, S; Boltana, S; Vargas, R; Roher, N; Mackenzie, S

2013-12-01

Resolving phenotype variation within a population in response to environmental perturbation is central to understanding biological adaptation. Relating meaningful adaptive changes at the level of the transcriptome requires the identification of processes that have a functional significance for the individual. This remains a major objective towards understanding the complex interactions between environmental demand and an individual's capacity to respond to such demands. The interpretation of such interactions and the significance of biological variation between individuals from the same or different populations remain a difficult and under-addressed question. Here, we provide evidence that variation in gene expression between individuals in a zebrafish population can be partially resolved by a priori screening for animal personality and accounts for >9% of observed variation in the brain transcriptome. Proactive and reactive individuals within a wild-type population exhibit consistent behavioural responses over time and context that relates to underlying differences in regulated gene networks and predicted protein-protein interactions. These differences can be mapped to distinct regions of the brain and provide a foundation towards understanding the coordination of underpinning adaptive molecular events within populations. © 2013 John Wiley & Sons Ltd.

Evidence of cryptic individual specialization in an opportunistic insectivorous bat

USGS Publications Warehouse

Cryan, Paul M.; Stricker, Craig A.; Wunder, Michael B.

2012-01-01

Habitat use and feeding behaviors of cryptic animals are often poorly understood. Analyses of stable isotope ratios in animal body tissues can help reveal an individual's location and resource use during tissue growth. We investigated variation in stable isotope ratios of 4 elements (H, C, N, and S) in the hair of a sedentary species of insectivorous bat (Eptesicus fuscus) inhabiting a chemically complex urban landscape. Our objective was to quantify population-level isotopic variation and test for evidence of resource specialization by individuals. Bats were sampled over 3 annual molt cycles at maternity roosts in buildings and variance components analysis was used to test whether intraindividual isotopic variation among molts differed from interindividual variation, after controlling for year and roost-group effects. Consistent with prior evidence that E. fuscus is opportunistic in its habitat use and foraging at the population level, we observed wide population-level variation for all isotopes. This variation likely reflects the chemical complexity of the urban landscape studied. However, isotopic variation among years within marked individuals was lower than variation among marked individuals within year for all isotopes, and carbon signatures indicated resource specialization by roost groups and individuals. This is the 1st study to examine variation in stable isotope ratios of individual wild bats over multiple years. Although our results suggest this population tends toward opportunistic habitat use or prey selection, or both, during molt periods, results also indicate that individuals and groups of bats composing the population might be habitat or dietary specialists—a novel finding for insectivorous bats.

Population-genetic properties of differentiated copy number variations in cattle

USDA-ARS?s Scientific Manuscript database

Copy number variations (CNVs) have been shown to be both common in mammals and important for understanding the relationship between genotype and phenotype. However, CNV differentiation, selection and its population genetic properties are not well understood across diverse populations. We performed a...

A continuum of admixture in the Western Hemisphere revealed by the African Diaspora genome

PubMed Central

Mathias, Rasika Ann; Taub, Margaret A.; Gignoux, Christopher R.; Fu, Wenqing; Musharoff, Shaila; O'Connor, Timothy D.; Vergara, Candelaria; Torgerson, Dara G.; Pino-Yanes, Maria; Shringarpure, Suyash S.; Huang, Lili; Rafaels, Nicholas; Boorgula, Meher Preethi; Johnston, Henry Richard; Ortega, Victor E.; Levin, Albert M.; Song, Wei; Torres, Raul; Padhukasahasram, Badri; Eng, Celeste; Mejia-Mejia, Delmy-Aracely; Ferguson, Trevor; Qin, Zhaohui S.; Scott, Alan F.; Yazdanbakhsh, Maria; Wilson, James G.; Marrugo, Javier; Lange, Leslie A.; Kumar, Rajesh; Avila, Pedro C.; Williams, L. Keoki; Watson, Harold; Ware, Lorraine B.; Olopade, Christopher; Olopade, Olufunmilayo; Oliveira, Ricardo; Ober, Carole; Nicolae, Dan L.; Meyers, Deborah; Mayorga, Alvaro; Knight-Madden, Jennifer; Hartert, Tina; Hansel, Nadia N.; Foreman, Marilyn G.; Ford, Jean G.; Faruque, Mezbah U.; Dunston, Georgia M.; Caraballo, Luis; Burchard, Esteban G.; Bleecker, Eugene; Araujo, Maria Ilma; Herrera-Paz, Edwin Francisco; Gietzen, Kimberly; Grus, Wendy E.; Bamshad, Michael; Bustamante, Carlos D.; Kenny, Eimear E.; Hernandez, Ryan D.; Beaty, Terri H.; Ruczinski, Ingo; Akey, Joshua; Campbell, Monica; Chavan, Sameer; Foster, Cassandra; Gao, Li; Horowitz, Edward; Ortiz, Romina; Potee, Joseph; Gao, Jingjing; Hu, Yijuan; Hansen, Mark; Deshpande, Aniket; Locke, Devin P.; Grammer, Leslie; Kim, Kwang-YounA; Schleimer, Robert; De La Vega, Francisco M.; Szpiech, Zachary A.; Oluwole, Oluwafemi; Arinola, Ganiyu; Correa, Adolfo; Musani, Solomon; Chong, Jessica; Nickerson, Deborah; Reiner, Alexander; Maul, Pissamai; Maul, Trevor; Martinez, Beatriz; Meza, Catherine; Ayestas, Gerardo; Landaverde-Torres, Pamela; Erazo, Said Omar Leiva; Martinez, Rosella; Mayorga, Luis F.; Ramos, Hector; Saenz, Allan; Varela, Gloria; Vasquez, Olga Marina; Samms-Vaughan, Maureen; Wilks, Rainford J.; Adegnika, Akim; Ateba-Ngoa, Ulysse; Barnes, Kathleen C.

2016-01-01

The African Diaspora in the Western Hemisphere represents one of the largest forced migrations in history and had a profound impact on genetic diversity in modern populations. To date, the fine-scale population structure of descendants of the African Diaspora remains largely uncharacterized. Here we present genetic variation from deeply sequenced genomes of 642 individuals from North and South American, Caribbean and West African populations, substantially increasing the lexicon of human genomic variation and suggesting much variation remains to be discovered in African-admixed populations in the Americas. We summarize genetic variation in these populations, quantifying the postcolonial sex-biased European gene flow across multiple regions. Moreover, we refine estimates on the burden of deleterious variants carried across populations and how this varies with African ancestry. Our data are an important resource for empowering disease mapping studies in African-admixed individuals and will facilitate gene discovery for diseases disproportionately affecting individuals of African ancestry. PMID:27725671

Balancing selection and genetic drift at major histocompatibility complex class II genes in isolated populations of golden snub-nosed monkey (Rhinopithecus roxellana)

PubMed Central

2012-01-01

Background Small, isolated populations often experience loss of genetic variation due to random genetic drift. Unlike neutral or nearly neutral markers (such as mitochondrial genes or microsatellites), major histocompatibility complex (MHC) genes in these populations may retain high levels of polymorphism due to balancing selection. The relative roles of balancing selection and genetic drift in either small isolated or bottlenecked populations remain controversial. In this study, we examined the mechanisms maintaining polymorphisms of MHC genes in small isolated populations of the endangered golden snub-nosed monkey (Rhinopithecus roxellana) by comparing genetic variation found in MHC and microsatellite loci. There are few studies of this kind conducted on highly endangered primate species. Results Two MHC genes were sequenced and sixteen microsatellite loci were genotyped from samples representing three isolated populations. We isolated nine DQA1 alleles and sixteen DQB1 alleles and validated expression of the alleles. Lowest genetic variation for both MHC and microsatellites was found in the Shennongjia (SNJ) population. Historical balancing selection was revealed at both the DQA1 and DQB1 loci, as revealed by excess non-synonymous substitutions at antigen binding sites (ABS) and maximum-likelihood-based random-site models. Patterns of microsatellite variation revealed population structure. FST outlier analysis showed that population differentiation at the two MHC loci was similar to the microsatellite loci. Conclusions MHC genes and microsatellite loci showed the same allelic richness pattern with the lowest genetic variation occurring in SNJ, suggesting that genetic drift played a prominent role in these isolated populations. As MHC genes are subject to selective pressures, the maintenance of genetic variation is of particular interest in small, long-isolated populations. The results of this study may contribute to captive breeding and translocation programs for endangered species. PMID:23083308

Biomedical research, a tool to address the health issues that affect African populations

PubMed Central

2013-01-01

Traditionally, biomedical research endeavors in low to middle resources countries have focused on communicable diseases. However, data collected over the past 20 years by the World Health Organization (WHO) show a significant increase in the number of people suffering from non-communicable diseases (e.g. heart disease, diabetes, cancer and pulmonary diseases). Within the coming years, WHO predicts significant decreases in communicable diseases while non-communicable diseases are expected to double in low and middle income countries in sub-Saharan Africa. The predicted increase in the non-communicable diseases population could be economically burdensome for the basic healthcare infrastructure of countries that lack resources to address this emerging disease burden. Biomedical research could stimulate development of healthcare and biomedical infrastructure. If this development is sustainable, it provides an opportunity to alleviate the burden of both communicable and non-communicable diseases through diagnosis, prevention and treatment. In this paper, we discuss how research using biomedical technology, especially genomics, has produced data that enhances the understanding and treatment of both communicable and non-communicable diseases in sub-Saharan Africa. We further discuss how scientific development can provide opportunities to pursue research areas responsive to the African populations. We limit our discussion to biomedical research in the areas of genomics due to its substantial impact on the scientific community in recent years however, we also recognize that targeted investments in other scientific disciplines could also foster further development in African countries. PMID:24143865

Testing the predictive power of cognitive atypicalities in autistic children: evidence from a 3-year follow-up study.

PubMed

Pellicano, Elizabeth

2013-08-01

This follow-up study investigated the predictive power of early cognitive atypicalities. Specifically, it examined whether early individual differences in specific cognitive skills, including theory of mind, executive function, and central coherence, could uniquely account for variation in autistic children's behaviors-social communication, repetitive behaviors, and interests and insistence on sameness-at follow-up. Thirty-seven cognitively able children with an autism spectrum condition were assessed on tests tapping verbal and nonverbal ability, theory of mind (false-belief prediction), executive function (planning ability, cognitive flexibility, and inhibitory control), and central coherence (local processing) at intake and their behavioral functioning (social communication, repetitive behaviors and interests, insistence on sameness) 3 years later. Individual differences in early executive but not theory of mind skills predicted variation in children's social communication. Individual differences in children's early executive function also predicted the degree of repetitive behaviors and interests at follow-up. There were no predictive relationships between early central coherence and children's insistence on sameness. These findings challenge the notion that distinct cognitive atypicalities map on to specific behavioral features of autism. Instead, early variation in executive function plays a key role in helping to shape autistic children's emerging behaviors, including their social communication and repetitive behaviors and interests. © 2013 International Society for Autism Research, Wiley Periodicals, Inc.

Insular Celtic population structure and genomic footprints of migration

PubMed Central

Hellenthal, Garrett

2018-01-01

Previous studies of the genetic landscape of Ireland have suggested homogeneity, with population substructure undetectable using single-marker methods. Here we have harnessed the haplotype-based method fineSTRUCTURE in an Irish genome-wide SNP dataset, identifying 23 discrete genetic clusters which segregate with geographical provenance. Cluster diversity is pronounced in the west of Ireland but reduced in the east where older structure has been eroded by historical migrations. Accordingly, when populations from the neighbouring island of Britain are included, a west-east cline of Celtic-British ancestry is revealed along with a particularly striking correlation between haplotypes and geography across both islands. A strong relationship is revealed between subsets of Northern Irish and Scottish populations, where discordant genetic and geographic affinities reflect major migrations in recent centuries. Additionally, Irish genetic proximity of all Scottish samples likely reflects older strata of communication across the narrowest inter-island crossing. Using GLOBETROTTER we detected Irish admixture signals from Britain and Europe and estimated dates for events consistent with the historical migrations of the Norse-Vikings, the Anglo-Normans and the British Plantations. The influence of the former is greater than previously estimated from Y chromosome haplotypes. In all, we paint a new picture of the genetic landscape of Ireland, revealing structure which should be considered in the design of studies examining rare genetic variation and its association with traits. PMID:29370172

Variations in influenza vaccination coverage among the high-risk population in Sweden in 2003/4 and 2004/5: a population survey

PubMed Central

Kroneman, Madelon W; van Essen, Gerrit A

2007-01-01

Background In Sweden, the vaccination campaign is the individual responsibility of the counties, which results in different arrangements. The aim of this study was to find out whether influenza vaccination coverage rates (VCRs) had increased between 2003/4 and 2004/5 among population at high risk and to find out the influence of personal preferences, demographic characteristics and health care system characteristics on VCRs. Methods An average sample of 2500 persons was interviewed each season (2003/4 and 2004/5). The respondents were asked whether they had had an influenza vaccination, whether they suffered from chronic conditions and the reasons of non-vaccination. For every county the relevant health care system characteristics were collected via a questionnaire sent to the medical officers of communicable diseases. Results No difference in VCR was found between the two seasons. Personal invitations strongly increased the chance of having had a vaccination. For the elderly, the number of different health care professionals in a region involved in administering vaccines decreased this chance. Conclusion Sweden remained below the WHO-recommendations for population at high risk due to disease. To meet the 2010 WHO-recommendation further action may be necessary to increase vaccine uptake. Increasing the number of personal invitations and restricting the number of different administrators responsible for vaccination may be effective in increasing VCRs among the elderly. PMID:17570837

Intra-population variation in activity ranges, diel patterns, movement rates, and habitat use of American alligators in a subtropical estuary

USGS Publications Warehouse

Rosenblatt, Adam E.; Heithaus, Michael R.; Mazzotti, Frank M; Cherkiss, Michael S.; Jeffery, Brian M.

2013-01-01

Movement and habitat use patterns are fundamental components of the behaviors of mobile animals and help determine the scale and types of interactions they have with their environments. These behaviors are especially important to quantify for top predators because they can have strong effects on lower trophic levels as well as the wider ecosystem. Many studies of top predator movement and habitat use focus on general population level trends, which may overlook important intra-population variation in behaviors that now appear to be common. In an effort to better understand the prevalence of intrapopulation variation in top predator movement behaviors and the potential effects of such variation on ecosystem dynamics, we examined the movement and habitat use patterns of a population of adult American alligators (Alligator mississippiensis) in a subtropical estuary for nearly four years. We found that alligators exhibited divergent behaviors with respect to activity ranges, movement rates, and habitat use, and that individualized behaviors were stable over multiple years. We also found that the variations across the three behavioral metrics were correlated such that consistent behavioral types emerged, specifically more exploratory individuals and more sedentary individuals. Our study demonstrates that top predator populations can be characterized by high degrees of intra-population variation in terms of movement and habitat use behaviors that could lead to individuals filling different ecological roles in the same ecosystem. By extension, one-size-fits-all ecosystem and species-specific conservation and management strategies that do not account for potential intra-population variation in top predator behaviors may not produce the desired outcomes in all cases.

Advertisement call and genetic structure conservatism: good news for an endangered Neotropical frog

PubMed Central

Costa, William P.; Martins, Lucas B.; Nunes-de-Almeida, Carlos H. L.; Toledo, Luís Felipe

2016-01-01

Background: Many amphibian species are negatively affected by habitat change due to anthropogenic activities. Populations distributed over modified landscapes may be subject to local extinction or may be relegated to the remaining—likely isolated and possibly degraded—patches of available habitat. Isolation without gene flow could lead to variability in phenotypic traits owing to differences in local selective pressures such as environmental structure, microclimate, or site-specific species assemblages. Methods: Here, we tested the microevolution hypothesis by evaluating the acoustic parameters of 349 advertisement calls from 15 males from six populations of the endangered amphibian species Proceratophrys moratoi. In addition, we analyzed the genetic distances among populations and the genetic diversity with a haplotype network analysis. We performed cluster analysis on acoustic data based on the Bray-Curtis index of similarity, using the UPGMA method. We correlated acoustic dissimilarities (calculated by Euclidean distance) with geographical and genetic distances among populations. Results: Spectral traits of the advertisement call of P. moratoi presented lower coefficients of variation than did temporal traits, both within and among males. Cluster analyses placed individuals without congruence in population or geographical distance, but recovered the species topology in relation to sister species. The genetic distance among populations was low; it did not exceed 0.4% for the most distant populations, and was not correlated with acoustic distance. Discussion: Both acoustic features and genetic sequences are highly conserved, suggesting that populations could be connected by recent migrations, and that they are subject to stabilizing selective forces. Although further studies are required, these findings add to a growing body of literature suggesting that this species would be a good candidate for a reintroduction program without negative effects on communication or genetic impact. PMID:27190717

Advertisement call and genetic structure conservatism: good news for an endangered Neotropical frog.

PubMed

Forti, Lucas R; Costa, William P; Martins, Lucas B; Nunes-de-Almeida, Carlos H L; Toledo, Luís Felipe

2016-01-01

Many amphibian species are negatively affected by habitat change due to anthropogenic activities. Populations distributed over modified landscapes may be subject to local extinction or may be relegated to the remaining-likely isolated and possibly degraded-patches of available habitat. Isolation without gene flow could lead to variability in phenotypic traits owing to differences in local selective pressures such as environmental structure, microclimate, or site-specific species assemblages. Here, we tested the microevolution hypothesis by evaluating the acoustic parameters of 349 advertisement calls from 15 males from six populations of the endangered amphibian species Proceratophrys moratoi. In addition, we analyzed the genetic distances among populations and the genetic diversity with a haplotype network analysis. We performed cluster analysis on acoustic data based on the Bray-Curtis index of similarity, using the UPGMA method. We correlated acoustic dissimilarities (calculated by Euclidean distance) with geographical and genetic distances among populations. Spectral traits of the advertisement call of P. moratoi presented lower coefficients of variation than did temporal traits, both within and among males. Cluster analyses placed individuals without congruence in population or geographical distance, but recovered the species topology in relation to sister species. The genetic distance among populations was low; it did not exceed 0.4% for the most distant populations, and was not correlated with acoustic distance. Both acoustic features and genetic sequences are highly conserved, suggesting that populations could be connected by recent migrations, and that they are subject to stabilizing selective forces. Although further studies are required, these findings add to a growing body of literature suggesting that this species would be a good candidate for a reintroduction program without negative effects on communication or genetic impact.

Subspecific affinity of black bears in the White River National Wildlife Refuge

USGS Publications Warehouse

Warrillow, J.; Culver, M.; Hallerman, E.; Vaughan, M.

2001-01-01

The black bear population of the White River National Wildlife Refuge (NWR) is adjacent to populations of black bear in Louisiana (Urusus americanus luteolus) which are listed as threatened under the U.S. Endangered Species Act. Wildlife management plans can pose restrictions on bear harvests and timber extraction; therefore the management plan for the White River NWR is sensitive to subspecific classification of its bear population. The objective of this study was to analyze genetic variation in the White River NWR and seven adjacent populations of black bears to assess the subspecific affinity of the White River NWR population. Here we report the variation at seven microsatellite DNA loci among eight black bear populations. The patterns of genetic variation gave strong support for distinguishing a southern group of black bears comprised of the White River, Arkansas; Tensas River, Louisiana; Upper Atchafalaya, Louisiana; Lower Atchafalaya, Louisiana; and Alabama/Mississippi populations. Phylogenetic analysis of individual variation suggested that historical black bear introductions into Arkansas and Louisiana affected gene pools of certain southern receiving populations, but did not significantly change interpopulation relatedness. Phylogenetic inferences at both the population and individual levels support the hypothesis that the White River NWR population of black bears belongs to the U. a. luteolus subspecies.

Subspecific affinity of black bears in the White River National Wildlife Refuge.

PubMed

Warrillow, J; Culver, M; Hallerman, E; Vaughan, M

2001-01-01

The black bear population of the White River National Wildlife Refuge (NWR) is adjacent to populations of black bear in Louisiana (Urusus americanus luteolus) which are listed as threatened under the U.S. Endangered Species Act. Wildlife management plans can pose restrictions on bear harvests and timber extraction; therefore the management plan for the White River NWR is sensitive to subspecific classification of its bear population. The objective of this study was to analyze genetic variation in the White River NWR and seven adjacent populations of black bears to assess the subspecific affinity of the White River NWR population. Here we report the variation at seven microsatellite DNA loci among eight black bear populations. The patterns of genetic variation gave strong support for distinguishing a southern group of black bears comprised of the White River, Arkansas; Tensas River, Louisiana; Upper Atchafalaya, Louisiana; Lower Atchafalaya, Louisiana; and Alabama/Mississippi populations. Phylogenetic analysis of individual variation suggested that historical black bear introductions into Arkansas and Louisiana affected gene pools of certain southern receiving populations, but did not significantly change interpopulation relatedness. Phylogenetic inferences at both the population and individual levels support the hypothesis that the White River NWR population of black bears belongs to the U. a. luteolus subspecies.

Intraspecific chromosome number variation: a neglected threat to the conservation of rare plants.

PubMed

Severns, Paul M; Liston, Aaron

2008-12-01

The effectiveness of rare plant conservation will increase when life history, demographic, and genetic data are considered simultaneously. Inbreeding depression is a widely recognized genetic concern in rare plant conservation, and the mixing of genetically diverse populations in restoration efforts is a common remedy. Nevertheless, if populations with unrecognized intraspecific chromosome variation are crossed, progeny fitness losses will range from partial to complete sterility, and reintroductions and population augmentation of rare plants may fail. To assess the current state of cytological knowledge of threatened and endangered plants in the continental United States, we searched available resources for chromosome counts. We also reviewed recovery plans to discern whether recovery criteria potentially place listed species at risk by requiring reintroductions or population augmentation in the absence of cytological information. Over half the plants lacked a chromosome count, and when a taxon did have a count it generally originated from a sampling intensity too limited to detect intraspecific chromosome variation. Despite limited past cytological sampling, we found 11 plants with documented intraspecific cytological variation, while 8 others were ambiguous for intraspecific chromosome variation. Nevertheless, only one recovery plan addressed the chromosome differences. Inadequate within-species cytological characterization, incomplete sampling among listed taxa, and the prevalence of interspecific and intraspecific chromosome variation in listed genera, suggests that other rare plants are likely to have intraspecific chromosome variation. Nearly 90% of all recovery plans called for reintroductions or population augmentation as part of recovery criteria despite the dearth of cytological knowledge. We recommend screening rare plants for intraspecific chromosome variation before reintroductions or population augmentation projects are undertaken to safeguard against inadvertent mixtures of incompatible cytotypes.

Effects of recruitment, growth, and exploitation on walleye population size structure in northern Wisconsin lakes

USGS Publications Warehouse

Hansen, Michael J.; Nate, Nancy A.

2014-01-01

We evaluated the dynamics of walleye Sander vitreus population size structure, as indexed by the proportional size distribution (PSD) of quality-length fish, in Escanaba Lake during 1967–2003 and in 204 other lakes in northern Wisconsin during 1990–2011. We estimated PSD from angler-caught walleyes in Escanaba Lake and from spring electrofishing in 204 other lakes, and then related PSD to annual estimates of recruitment to age-3, length at age 3, and annual angling exploitation rate. In Escanaba Lake during 1967–2003, annual estimates of PSD were highly dynamic, growth (positively) explained 35% of PSD variation, recruitment explained only 3% of PSD variation, and exploitation explained only 7% of PSD variation. In 204 other northern Wisconsin lakes during 1990–2011, PSD varied widely among lakes, recruitment (negatively) explained 29% of PSD variation, growth (positively) explained 21% of PSD variation, and exploitation explained only 4% of PSD variation. We conclude that population size structure was most strongly driven by recruitment and growth, rather than exploitation, in northern Wisconsin walleye populations. Studies of other species over wide spatial and temporal ranges of recruitment, growth, and mortality are needed to determine which dynamic rate most strongly influences population size structure of other species. Our findings indicate a need to be cautious about assuming exploitation is a strong driver of walleye population size structure.

Climate variables explain neutral and adaptive variation within salmonid metapopulations: The importance of replication in landscape genetics

USGS Publications Warehouse

Hand, Brian K.; Muhlfeld, Clint C.; Wade, Alisa A.; Kovach, Ryan; Whited, Diane C.; Narum, Shawn R.; Matala, Andrew P.; Ackerman, Michael W.; Garner, B. A.; Kimball, John S; Stanford, Jack A.; Luikart, Gordon

2016-01-01

Understanding how environmental variation influences population genetic structure is important for conservation management because it can reveal how human stressors influence population connectivity, genetic diversity and persistence. We used riverscape genetics modelling to assess whether climatic and habitat variables were related to neutral and adaptive patterns of genetic differentiation (population-specific and pairwise FST) within five metapopulations (79 populations, 4583 individuals) of steelhead trout (Oncorhynchus mykiss) in the Columbia River Basin, USA. Using 151 putatively neutral and 29 candidate adaptive SNP loci, we found that climate-related variables (winter precipitation, summer maximum temperature, winter highest 5% flow events and summer mean flow) best explained neutral and adaptive patterns of genetic differentiation within metapopulations, suggesting that climatic variation likely influences both demography (neutral variation) and local adaptation (adaptive variation). However, we did not observe consistent relationships between climate variables and FST across all metapopulations, underscoring the need for replication when extrapolating results from one scale to another (e.g. basin-wide to the metapopulation scale). Sensitivity analysis (leave-one-population-out) revealed consistent relationships between climate variables and FST within three metapopulations; however, these patterns were not consistent in two metapopulations likely due to small sample sizes (N = 10). These results provide correlative evidence that climatic variation has shaped the genetic structure of steelhead populations and highlight the need for replication and sensitivity analyses in land and riverscape genetics.

Translating Alcohol Research

PubMed Central

Batman, Angela M.; Miles, Michael F.

2015-01-01

Alcohol use disorder (AUD) and its sequelae impose a major burden on the public health of the United States, and adequate long-term control of this disorder has not been achieved. Molecular and behavioral basic science research findings are providing the groundwork for understanding the mechanisms underlying AUD and have identified multiple candidate targets for ongoing clinical trials. However, the translation of basic research or clinical findings into improved therapeutic approaches for AUD must become more efficient. Translational research is a multistage process of streamlining the movement of basic biomedical research findings into clinical research and then to the clinical target populations. This process demands efficient bidirectional communication across basic, applied, and clinical science as well as with clinical practitioners. Ongoing work suggests rapid progress is being made with an evolving translational framework within the alcohol research field. This is helped by multiple interdisciplinary collaborative research structures that have been developed to advance translational work on AUD. Moreover, the integration of systems biology approaches with collaborative clinical studies may yield novel insights for future translational success. Finally, appreciation of genetic variation in pharmacological or behavioral treatment responses and optimal communication from bench to bedside and back may strengthen the success of translational research applications to AUD. PMID:26259085

Translating Alcohol Research: Opportunities and Challenges.

PubMed

Batman, Angela M; Miles, Michael F

2015-01-01

Alcohol use disorder (AUD) and its sequelae impose a major burden on the public health of the United States, and adequate long-term control of this disorder has not been achieved. Molecular and behavioral basic science research findings are providing the groundwork for understanding the mechanisms underlying AUD and have identified multiple candidate targets for ongoing clinical trials. However, the translation of basic research or clinical findings into improved therapeutic approaches for AUD must become more efficient. Translational research is a multistage process of stream-lining the movement of basic biomedical research findings into clinical research and then to the clinical target populations. This process demands efficient bidirectional communication across basic, applied, and clinical science as well as with clinical practitioners. Ongoing work suggests rapid progress is being made with an evolving translational framework within the alcohol research field. This is helped by multiple interdisciplinary collaborative research structures that have been developed to advance translational work on AUD. Moreover, the integration of systems biology approaches with collaborative clinical studies may yield novel insights for future translational success. Finally, appreciation of genetic variation in pharmacological or behavioral treatment responses and optimal communication from bench to bedside and back may strengthen the success of translational research applications to AUD.

The communicative potential of bat echolocation pulses.

PubMed

Jones, Gareth; Siemers, Björn M

2011-05-01

Ecological constraints often shape the echolocation pulses emitted by bat species. Consequently some (but not all) bats emit species-specific echolocation pulses. Because echolocation pulses are often intense and emitted at high rates, they are potential targets for eavesdropping by other bats. Echolocation pulses can also vary within species according to sex, body size, age, social group and geographic location. Whether these features can be recognised by other bats can only be determined reliably by playback experiments, which have shown that echolocation pulses do provide sufficient information for the identification of sex and individual in one species. Playbacks also show that bats can locate conspecifics and heterospecifics at foraging and roost sites by eavesdropping on echolocation pulses. Guilds of echolocating bat species often partition their use of pulse frequencies. Ecology, allometric scaling and phylogeny play roles here, but are not sufficient to explain this partitioning. Evidence is accumulating to support the hypothesis that frequency partitioning evolved to facilitate intraspecific communication. Acoustic character displacement occurs in at least one instance. Future research can relate genetic population structure to regional variation in echolocation pulse features and elucidate those acoustic features that most contribute to discrimination of individuals.

The acoustic adaptation hypothesis in a widely distributed South American frog: Southernmost signals propagate better.

PubMed

Velásquez, Nelson A; Moreno-Gómez, Felipe N; Brunetti, Enzo; Penna, Mario

2018-05-03

Animal communication occurs in environments that affect the properties of signals as they propagate from senders to receivers. We studied the geographic variation of the advertisement calls of male Pleurodema thaul individuals from eight localities in Chile. Furthermore, by means of signal propagation experiments, we tested the hypothesis that local calls are better transmitted and less degraded than foreign calls (i.e. acoustic adaptation hypothesis). Overall, the advertisement calls varied greatly along the distribution of P. thaul in Chile, and it was possible to discriminate localities grouped into northern, central and southern stocks. Propagation distance affected signal amplitude and spectral degradation in all localities, but temporal degradation was only affected by propagation distance in one out of seven localities. Call origin affected signal amplitude in five out of seven localities and affected spectral and temporal degradation in six out of seven localities. In addition, in northern localities, local calls degraded more than foreign calls, and in southern localities the opposite was observed. The lack of a strict optimal relationship between signal characteristics and environment indicates partial concordance with the acoustic adaptation hypothesis. Inter-population differences in selectivity for call patterns may compensate for such environmental constraints on acoustic communication.

Responsibilities and resources of on-call public health doctors.

PubMed

Sarangi, J; Mackenzie, I; Pearson, N

1995-01-01

We investigated the resource available for public health doctors to carry out statutory responsibilities out-of-hours by a postal questionnaire survey of consultants in communicable disease control (CsCDC) in England and Wales. The questionnaire requested details of local District Health Authority (DHA) population profile, major incident and outbreak policies, the background of the CCDC, out-of-hours communication, access and resources, reference materials and medical equipment carried by the public health doctor on duty. The CsCDC from 96% (121/126) DHAs in England and Wales responded. Whilst 85% (101/119) of public health doctors carried policies on infectious disease when on duty, only 28% (32/116) carried policies on dealing with chemical incidents and 25% (28/111) carried the District policy to deal with radiation hazards. Twenty-six per cent (32/121) of public health physicians had no access to their District headquarters. There is a wide variation in the standard of resources available to on-call public health doctors in England and Wales; following Department of Health and Department of the Environment guidance, Health Authorities need to ensure that they have adequate arrangements in the event of any major incident or outbreak.

The Internet, Intercultural Communication and Cultural Variation

ERIC Educational Resources Information Center

Marcoccia, Michel

2012-01-01

The internet affords its users an unprecedented level of contact with people from other cultural and social groups. It is often assumed that because of this it can facilitate intercultural communication and reduce the perceived distance between cultures. This article will examine this assumption by exploring two questions. Firstly, do the…

7 CFR 1755.397 - RUS performance specification for line concentrators.

Code of Federal Regulations, 2014 CFR

2014-01-01

... variation of ±1.5 percent: Low group frequencies (Hz) High group frequencies (Hz) 1209 1336 1477 1633 697 1... for Electrical Purposes. (ii) [Reserved] (5) Bell Communications Research (Bellcore) standards are... System and a Local Digital Switch. (ii) Bell Communications Research (Bellcore) document TR-TSY-000057...

7 CFR 1755.397 - RUS performance specification for line concentrators.

Code of Federal Regulations, 2012 CFR

2012-01-01

... variation of ±1.5 percent: Low group frequencies (Hz) High group frequencies (Hz) 1209 1336 1477 1633 697 1... for Electrical Purposes. (ii) [Reserved] (5) Bell Communications Research (Bellcore) standards are... System and a Local Digital Switch. (ii) Bell Communications Research (Bellcore) document TR-TSY-000057...

7 CFR 1755.397 - RUS performance specification for line concentrators.

Code of Federal Regulations, 2011 CFR

2011-01-01

... variation of ±1.5 percent: Low group frequencies (Hz) High group frequencies (Hz) 1209 1336 1477 1633 697 1... for Electrical Purposes. (ii) [Reserved] (5) Bell Communications Research (Bellcore) standards are... System and a Local Digital Switch. (ii) Bell Communications Research (Bellcore) document TR-TSY-000057...

7 CFR 1755.397 - RUS performance specification for line concentrators.

Code of Federal Regulations, 2013 CFR

2013-01-01

... variation of ±1.5 percent: Low group frequencies (Hz) High group frequencies (Hz) 1209 1336 1477 1633 697 1... for Electrical Purposes. (ii) [Reserved] (5) Bell Communications Research (Bellcore) standards are... System and a Local Digital Switch. (ii) Bell Communications Research (Bellcore) document TR-TSY-000057...

English Face-to-Face: The Non-Verbal Dimension of Conversation.

ERIC Educational Resources Information Center

Bachmann, James K.

Nonverbal communication is important in foreign language teaching and learning because of its variation in form, meaning and distribution from one culture to another and because of its extensive use in the communicative process. Cross-cultural misunderstandings result from incorrect interpretations of the tone of voice, body motions, facial…

Students' Orientation towards Interpersonal Communication in Online Social Networking Sites

ERIC Educational Resources Information Center

Kayode, Bakare Kazeem; Zamzami, Ikhlas F.; Olowolayemo, Akeem

2012-01-01

Purpose: As computer-mediated communication has diffused, successive technological variations raise new questions about interpersonal impressions and several standardized instruments have been advanced in literature to asses various aspect of interpersonal attraction phenomena. The purpose of this paper is to examine the claims for reliability and…

Population education in the nineties: a quest for a regional programme strategy in Asia and the Pacific.

PubMed

1991-01-01

In 1990, Asia and the Pacific constituted 59% of the world's population and this percentage has been estimated to climb to 61.76% by 1995. In addition to rapid population growth, some of the other problems plaguing the region in the early 1990s included illiteracy, absolute poverty, environmental pollution, and low status of women. Population education can play a key role in an intervention strategy for fertility decline. Schools should include population education because, if girls attend school, it can improve girls' chances for employment and affect future family sizes, and both male and female students are most apt to occupy important private sector and government positions and be leaders. UNESCO has proposed a 1992-1995 regional population education and communication program and hoped to gain UNFPA support for the program. UNESCO has heeded UNFPA's plea for more formidable and intensive backstopping to country programs. It proposed to create regional advisory teams that will provide technical assistance, organize study tours and workshops, facilitate intercountry sharing, and identify new areas of development. This team would also be population education advocates. It has also proposed a workshop in population communication for staff of rural oriented nongovernmental organizations and religious groups to close the UNFPA identified gap in information, education, and communication (IEC). Other similar proposed activities to close the IEC gap included workshops on audiovisual (AV) aids development and use and maintenance of AV equipment and on communication strategies to reach male family planning acceptors and intercountry research studies. UNESCO has also planned to place more emphasis on management, development of prototype population education materials, and other needed population education activities.

Sex-biased survival predicts adult sex ratio variation in wild birds.

PubMed

Székely, Tamás; Liker, András; Freckleton, Robert P; Fichtel, Claudia; Kappeler, Peter M

2014-08-07

Adult sex ratio (ASR) is a central concept in population demography and breeding system evolution, and has implications for population viability and biodiversity conservation. ASR exhibits immense interspecific variation in wild populations, although the causes of this variation have remained elusive. Using phylogenetic analyses of 187 avian species from 59 families, we show that neither hatching sex ratios nor fledging sex ratios correlate with ASR. However, sex-biased adult mortality is a significant predictor of ASR, and this relationship is robust to 100 alternative phylogenetic hypotheses, and potential ecological and life-history confounds. A significant component of adult mortality bias is sexual selection acting on males, whereas increased reproductive output predicts higher mortality in females. These results provide the most comprehensive insights into ASR variation to date, and suggest that ASR is an outcome of selective processes operating differentially on adult males and females. Therefore, revealing the causes of ASR variation in wild populations is essential for understanding breeding systems and population dynamics. © 2014 The Author(s) Published by the Royal Society. All rights reserved.

Development of the Communication Complexity Scale

PubMed Central

Brady, Nancy C.; Fleming, Kandace; Thiemann-Bourque, Kathy; Olswang, Lesley; Dowden, Patricia; Saunders, Muriel D.

2011-01-01

Accurate description of an individual's communication status is critical in both research and practice. Describing the communication status of individuals with severe intellectual and developmental disabilities is difficult because these individuals often communicate with presymbolic means that may not be readily recognized. Our goal was to design a communication scale and summary score for interpretation that could be applied across populations of children and adults with limited (often presymbolic) communication forms. Methods The Communication Complexity Scale (CCS) was developed by a team of researchers and tested with 178 participants with varying levels of presymbolic and early symbolic communication skills. Correlations between standardized and informant measures were completed, and expert opinions were obtained regarding the CCS. Results CCS scores were within expected ranges for the populations studied and inter-rater reliability was high. Comparison across other measures indicated significant correlations with standardized tests of language. Scores on informant report measures tended to place children at higher levels of communication. Expert opinions generally favored the development of the CCS. Clinical implications The scale appears to be useful for describing a given individual's level of presymbolic or early symbolic communication. Further research is needed to determine if it is sensitive to developmental growth in communication. PMID:22049404

Theme Issue on Health Communication.

ERIC Educational Resources Information Center

Anapol, Malthon M., Ed.

1979-01-01

The five articles in this publication address the following topics: the need for effective communication in the dental office, communication skills among preschool children with sickle cell disease, the use of qualifiers in medical headlines, population communication in India, and the effectiveness of a home care program in facilitating therapy…

Using a Parental Checklist to Identify Diagnostic Groups in Children with Communication Impairment: A Validation of the Children's Communication Checklist--2

ERIC Educational Resources Information Center

Norbury, Courtenay Frazier; Nash, Marysia; Baird, Gillian; Bishop, Dorothy V. M.

2004-01-01

Background: The Children's Communication Checklist (CCC 1998) was revised in 2003 (CCC-2) to provide a general screen for communication disorder and to identify pragmatic/social interaction deficits. Two validation studies were conducted with different populations of children with language and communication impairments. Methods & Procedures: In…

A quantitative analysis of phenotypic variations of Metrosideros polymorpha within and across populations along environmental gradients on Mauna Loa, Hawaii.

PubMed

Tsujii, Yuki; Onoda, Yusuke; Izuno, Ayako; Isagi, Yuji; Kitayama, Kanehiro

2016-04-01

Metrosideros polymorpha, a dominant tree species in the Hawaiian Islands, shows an extreme phenotypic polymorphism both across gradients of climatic/edaphic conditions and within populations, making it a potentially useful model species for evolutionary study. In order to understand how the phenotypic diversity is maintained within populations as well as across populations, we examined the diversities of several leaf and stem functional traits across five elevations and two soil substrates on the volcanic mountain of Mauna Loa, on the island of Hawaii. Leaf dry mass per area (LMA), a key leaf functional trait, was particularly focused on and analyzed in relation to its underlying components-namely, tissue LMA and trichome LMA (LMA = tissue LMA + trichome LMA). Across populations, tissue LMA increased linearly with elevation while trichome LMA showed unimodal patterns with elevation, which were better correlated with temperature and rainfall, respectively. Substantial phenotypic variations were also found within populations. Interestingly, the variations of tissue LMA were often negatively correlated to trichome LMA within populations, which contrasts with the cross-populations pattern, where a strong positive correlation between tissue LMA and trichome LMA was found. This suggests that phenotypic variations within populations were substantially influenced by local ecological processes. Soil depth (an indicator of local water availability) and tree size (an indicator of colonized timing) modestly explained the within-population variations, implying other local environmental factors and/or random processes are also important in local phenotypic diversity. This study provides an insight about how phenotypic diversity of plant species is maintained from local to landscape levels.

Snapshot of the supports of communication used by patients at a French psychiatric hospital: a digital or social division?

PubMed

Girard, Murielle; Nubukpo, Philippe; Malauzat, Dominique

2017-02-01

The role of information and communications technology is becoming increasingly prevalent in daily life and in the organization of medical care: are some people being left out? To evaluate access to and the uses of communication resources by psychiatric patients, focusing on the means of communication (e.g. mobile phones and computers), access and frequency of internet use. A questionnaire was distributed, over a period of 1 week, to inpatients or day hospitalised patients aged over 12 years in all care units. Access to and the uses of modern communication resources were lower than in the general population. Among places and means of internet consultation, the personal computer was most often cited, but only by 34%, and the use of mobile phones is still not widespread. Finally, day hospitalised subjects, the elderly, or subjects being treated in the psychosis care sector use internet and technology the least. Some differences exist between this population with mental illness and the general population on the use of new communication technologies. The possibility of integrating these techniques in individualized psychiatric care requires prior equipment and/or updates.

Population genetic structure of traditional populations in the Peruvian Central Andes and implications for South American population history.

PubMed

Cabana, Graciela S; Lewis, Cecil M; Tito, Raúl Y; Covey, R Alan; Cáceres, Angela M; Cruz, Augusto F De La; Durand, Diana; Housman, Genevieve; Hulsey, Brannon I; Iannacone, Gian Carlo; López, Paul W; Martínez, Rolando; Medina, Ángel; Dávila, Olimpio Ortega; Pinto, Karla Paloma Osorio; Santillán, Susan I Polo; Domínguez, Percy Rojas; Rubel, Meagan; Smith, Heather F; Smith, Silvia E; Massa, Verónica Rubín de Celis; Lizárraga, Beatriz; Stone, Anne C

2014-01-01

Molecular-based characterizations of Andean peoples are traditionally conducted in the service of elucidating continent-level evolutionary processes in South America. Consequently, genetic variation among "western" Andean populations is often represented in relation to variation among "eastern" Amazon and Orinoco River Basin populations. This west-east contrast in patterns of population genetic variation is typically attributed to large-scale phenomena, such as dual founder colonization events or differing long-term microevolutionary histories. However, alternative explanations that consider the nature and causes of population genetic diversity within the Andean region remain underexplored. Here we examine population genetic diversity in the Peruvian Central Andes using data from the mtDNA first hypervariable region and Y-chromosome short tandem repeats among 17 newly sampled populations and 15 published samples. Using this geographically comprehensive data set, we first reassessed the currently accepted pattern of western versus eastern population genetic structure, which our results ultimately reject: mtDNA population diversities were lower, rather than higher, within Andean versus eastern populations, and only highland Y-chromosomes exhibited significantly higher within-population diversities compared with eastern groups. Multiple populations, including several highland samples, exhibited low genetic diversities for both genetic systems. Second, we explored whether the implementation of Inca state and Spanish colonial policies starting at about ad 1400 could have substantially restructured population genetic variation and consequently constitute a primary explanation for the extant pattern of population diversity in the Peruvian Central Andes. Our results suggest that Peruvian Central Andean population structure cannot be parsimoniously explained as the sole outcome of combined Inca and Spanish policies on the region's population demography: highland populations differed from coastal and lowland populations in mtDNA genetic structure only; highland groups also showed strong evidence of female-biased gene flow and/or effective sizes relative to other Peruvian ecozones. Taken together, these findings indicate that population genetic structure in the Peruvian Central Andes is considerably more complex than previously reported and that characterizations of and explanations for genetic variation may be best pursued within more localized regions and defined time periods.

Spatial and temporal drivers of phenotypic diversity in polymorphic snakes.

PubMed

Cox, Christian L; Davis Rabosky, Alison R

2013-08-01

Color polymorphism in natural populations presents an ideal opportunity to study the evolutionary drivers of phenotypic diversity. Systems with striking spatial, temporal, and qualitative variation in color can be leveraged to study the mechanisms promoting the distribution of different types of variation in nature. We used the highly polymorphic ground snake (Sonora semiannulata), a putative coral snake mimic with both cryptic and conspicuous morphs, to compare patterns of neutral genetic variation and variation over space and time in color polymorphism to investigate the mechanistic drivers of phenotypic variation across scales. We found that strong selection promotes color polymorphism across spatial and temporal scales, with morph frequencies differing markedly between juvenile and adult age classes within a single population, oscillating over time within multiple populations, and varying drastically over the landscape despite minimal population genetic structure. However, we found no evidence that conspicuousness of morphs was related to which color pattern was favored by selection or to any geographic factors, including sympatry with coral snakes. We suggest that complex patterns of phenotypic variation in polymorphic systems may be a fundamental outcome of the conspicuousness of morphs and that explicit tests of temporal and geographic variation are critical to the interpretation of conspicuousness and mimicry.

Adolescent and parent use of new technologies for health communication: a study in an urban latino community.

PubMed

Smaldone, Arlene; Stockwell, Melissa S; Osborne, Jennel C; Cortes, Yamnia; Bekele, ElShadey; Green, Nancy S

2015-02-20

Mobile communication technologies provide novel opportunities to support clinic-based health initiatives. Adoption of technologies for daily use and for health communication can differ between communities, depending upon demographic and cultural characteristics. A survey was administered in adolescent primary care and subspecialty clinics to assess parent-adolescent preferences in use of mobile technologies and social media to support provider-patient communication in an urban Latino community. Of 130 respondents (65 parent-adolescent pairs), approximately half frequently sent and received text messages but lacked agreement regarding the other's text messaging use. In contrast, adolescents only rarely used email compared to parents (15.4% versus 37.5%, P=0.006). Of social media, Facebook™/MySpace™ was most frequently used by parents and youth (60% and 55.4%, P=0.59); however, most lacked interest in using social media for health communication. Parents reported more interest than adolescents in receiving email (73.4% versus 35.9%, P<0.001) and text messages (58.5% versus 33.9%, P=0.005) for health, but had more concerns about privacy issues (26.2% versus 9.2%, P=0.01). Respondents who were American born (aOR 5.7, 95%CI 1.2-28.5) or regularly used Instant Messaging or Facebook™/MySpace™ (aOR 4.6, 95%CI 1.4-14.7) were more likely to be interested in using social media for health communication. These findings underscore the importance of targeted assessment for planning the utilization of communication technologies and social media in clinical care or research for underserved youth. Significance for public healthCommunication technologies provide novel opportunities to support clinic-based health initiatives for underserved youth. However, adoption of technologies among communities may differ depending upon demographic and cultural characteristics. We surveyed a sample of urban Latino parents and youth regarding their current use of mobile and social media technologies and preferences for use of these technologies for health communication. This is the first study to compare the perspective of underserved parents and their youth regarding use of a wide variety of mobile and social communication technologies, concordance between youth-parent pairs in perceived use of texting and preferences for the purpose of health communication. Our findings differ from those from adults surveyed in other under-served communities, highlighting heterogeneity between communities. Variations in use of communication technologies and social media and preferences between parent-youth pairs suggest that understanding these factors within target populations is crucial for successful use to support health and health services.

Improving the quality of communication in organised cervical cancer screening programmes.

PubMed

Giordano, Livia; Webster, Premila; Anthony, Charles; Szarewski, Anne; Davies, Philip; Arbyn, Marc; Segnan, Nereo; Austoker, Joan

2008-07-01

To provide health professionals involved in cervical cancer screening with an insight into the complex issues relating to communication about screening and to provide a framework for a more effective communication strategy. This paper has been compiled by a multidisciplinary pan-European group of health professionals and cancer advocates from several European screening programmes. European surveys on screening communication, literature reviews and group discussion were used for this purpose. Information on cervical screening must be accessible, relevant, comprehensible, comprehensive, client-centred, phase-specific and multilevel. An effective communication strategy should consider health professionals' screening knowledge and their communication skills, consumers' health literacy skills and the communication needs of specific sub-groups in the target population. Co-operation between screening professionals, advocacy groups and journalists should be promoted. To communicate effectively and appropriately is a complex task which can be influenced by a number of factors. Screening workers need better information themselves and must take into account the needs and characteristics of the target population. This document should provide a useful tool to help screening professionals in designing and developing good quality and effective communication strategies.

Genetic variation of the endangered Gentiana lutea L. var. aurantiaca (Gentianaceae) in populations from the Northwest Iberian Peninsula.

PubMed

González-López, Oscar; Polanco, Carlos; György, Zsuzsanna; Pedryc, Andrzej; Casquero, Pedro A

2014-06-05

Gentiana lutea L. (G. lutea L.) is an endangered plant, patchily distributed along the mountains of Central and Southern Europe. In this study, inter-simple sequence repeat (ISSR) markers were used to investigate the genetic variation in this species within and among populations of G. lutea L. var. aurantiaca of the Cantabrian Mountains (Northwest Iberian Peninsula). Samples of G. lutea L. collected at different locations of the Pyrenees and samples of G. lutea L. subsp. vardjanii of the Dolomites Alps were also analyzed for comparison. Using nine ISSR primers, 106 bands were generated, and 89.6% of those were polymorphic. The populations from the Northwest Iberian Peninsula were clustered in three different groups, with a significant correlation between genetic and geographic distances. Gentiana lutea L. var. aurantiaca showed 19.8% private loci and demonstrated a remarkable level of genetic variation, both among populations and within populations; those populations with the highest level of isolation show the lowest genetic variation within populations. The low number of individuals, as well as the observed genetic structure of the analyzed populations makes it necessary to protect them to ensure their survival before they are too small to persist naturally.

Genetic Variation of the Endangered Gentiana lutea L. var. aurantiaca (Gentianaceae) in Populations from the Northwest Iberian Peninsula

PubMed Central

González-López, Oscar; Polanco, Carlos; György, Zsuzsanna; Pedryc, Andrzej; Casquero, Pedro A.

2014-01-01

Gentiana lutea L. (G. lutea L.) is an endangered plant, patchily distributed along the mountains of Central and Southern Europe. In this study, inter-simple sequence repeat (ISSR) markers were used to investigate the genetic variation in this species within and among populations of G. lutea L. var. aurantiaca of the Cantabrian Mountains (Northwest Iberian Peninsula). Samples of G. lutea L. collected at different locations of the Pyrenees and samples of G. lutea L. subsp. vardjanii of the Dolomites Alps were also analyzed for comparison. Using nine ISSR primers, 106 bands were generated, and 89.6% of those were polymorphic. The populations from the Northwest Iberian Peninsula were clustered in three different groups, with a significant correlation between genetic and geographic distances. Gentiana lutea L. var. aurantiaca showed 19.8% private loci and demonstrated a remarkable level of genetic variation, both among populations and within populations; those populations with the highest level of isolation show the lowest genetic variation within populations. The low number of individuals, as well as the observed genetic structure of the analyzed populations makes it necessary to protect them to ensure their survival before they are too small to persist naturally. PMID:24905405

Population structure and cultural geography of a folktale in Europe

PubMed Central

Ross, Robert M.; Greenhill, Simon J.; Atkinson, Quentin D.

2013-01-01

Despite a burgeoning science of cultural evolution, relatively little work has focused on the population structure of human cultural variation. By contrast, studies in human population genetics use a suite of tools to quantify and analyse spatial and temporal patterns of genetic variation within and between populations. Human genetic diversity can be explained largely as a result of migration and drift giving rise to gradual genetic clines, together with some discontinuities arising from geographical and cultural barriers to gene flow. Here, we adapt theory and methods from population genetics to quantify the influence of geography and ethnolinguistic boundaries on the distribution of 700 variants of a folktale in 31 European ethnolinguistic populations. We find that geographical distance and ethnolinguistic affiliation exert significant independent effects on folktale diversity and that variation between populations supports a clustering concordant with European geography. This pattern of geographical clines and clusters parallels the pattern of human genetic diversity in Europe, although the effects of geographical distance and ethnolinguistic boundaries are stronger for folktales than genes. Our findings highlight the importance of geography and population boundaries in models of human cultural variation and point to key similarities and differences between evolutionary processes operating on human genes and culture. PMID:23390109

Communication variations related to leader personality

NASA Technical Reports Server (NTRS)

Kanki, Barbara G.; Palmer, Mark T.; Veinott, Elizabeth S.

1991-01-01

While communication and captain personality type have been separately shown to relate to overall crew performance, this study attempts to establish a link between communication and personality among 12 crews whose captains represent three pre-selected personality profiles (IE+, I-, Ec-). Results from analyzing transcribed speech from one leg of a full-mission simulation study, so far indicate several discriminating patterns involving ratios of total initiating speech (captain to crew members); in particular commands, questions and observations.

Effects of Wolbachia on mitochondrial DNA variation in populations of Athetis lepigone (Lepidoptera: Noctuidae) in China

USDA-ARS?s Scientific Manuscript database

Wolbachia are endosymbiotic bacteria that infect arthropods and incompatibility among strains can affect gene flow within host insect populations, that can result in significant host mitochondrial DNA (MtD) variation. The effects of Wolbachia infection on mtDNA variation was studied in Athetis lepi...

Intercultural Leadership Toolkit for Librarians: Building Awareness to Effectively Serve Diverse Multicultural Populations

ERIC Educational Resources Information Center

Allard, Suzie; Mehra, Bharat; Qayyum, M. Asim

2007-01-01

This paper presents five tools for librarians to use in building effective intercultural communication that reaches out to diverse populations. Librarians can more successfully cross intercultural boundaries if they are aware of the key tenets of intercultural communication and information provision, and then apply the five leadership tools in…

Natural areas and urban populations: communication and environmental education challenges and actions in outdoor recreation

Treesearch

Deborah J. Chavez

2005-01-01

Challenges, opportunities, and actions exist in areas where large urban populations interface with natural areas, such as outdoor recreation sites in southern California. Challenges in the interface include intense recreation use, public safety issues, and complex information strategies. Research results on communications and environmental education offer opportunities...

New Bottles, Old Wine: Communicative Language Teaching in China.

ERIC Educational Resources Information Center

Hui, Leng

1997-01-01

As the largest English-learning population in the world, China is deeply involved in communicative language teaching (CLT). Because of economic, administrative, cultural, and population constraints, and the academic abilities of classroom teachers, China has to work to Adapt CLT to local conditions. This situation must be overcome or traditional,…

Within and between Population Variation in Epidermal Club Cell Investment in a Freshwater Prey Fish: A Cautionary Tale for Evolutionary Ecologists

PubMed Central

Manek, Aditya K.; Ferrari, Maud C. O.; Pollock, Robyn J.; Vicente, Daniel; Weber, Lynn P.; Chivers, Douglas P.

2013-01-01

Many prey fishes possess large club cells in their epidermis. The role of these cells has garnered considerable attention from evolutionary ecologists. These cells likely form part of the innate immune system of fishes, however, they also have an alarm function, releasing chemical cues that serve to warn nearby conspecifics of danger. Experiments aimed at understanding the selection pressures leading to the evolution of these cells have been hampered by a surprisingly large intraspecific variation in epidermal club cell (ECC) investment. The goal of our current work was to explore the magnitude and nature of this variation in ECC investment. In a field survey, we documented large differences in ECC investment both within and between several populations of minnows. We then tested whether we could experimentally reduce variation in mean ECC number by raising fish under standard laboratory conditions for 4 weeks. Fish from different populations responded very differently to being held under standard laboratory conditions; some populations showed an increase in ECC investment while others remained unchanged. More importantly, we found some evidence that we could reduce within population variation in ECC investment through time, but could not reduce among-population variation in mean ECC investment. Given the large variation we observed in wild fish and our limited ability to converge mean cell number by holding the fish under standard conditions, we caution that future studies may be hard pressed to find subtle effects of various experimental manipulations; this will make elucidating the selection pressures leading to the evolution of the cells challenging. PMID:23469175

Between-year variation in population sex ratio increases with complexity of the breeding system in Hymenoptera.

PubMed

Kümmerli, Rolf; Keller, Laurent

2011-06-01

While adaptive adjustment of sex ratio in the function of colony kin structure and food availability commonly occurs in social Hymenoptera, long-term studies have revealed substantial unexplained between-year variation in sex ratio at the population level. In order to identify factors that contribute to increased between-year variation in population sex ratio, we conducted a comparative analysis across 47 Hymenoptera species differing in their breeding system. We found that between-year variation in population sex ratio steadily increased as one moved from solitary species, to primitively eusocial species, to single-queen eusocial species, to multiple-queen eusocial species. Specifically, between-year variation in population sex ratio was low (6.6% of total possible variation) in solitary species, which is consistent with the view that in solitary species, sex ratio can vary only in response to fluctuations in ecological factors such as food availability. In contrast, we found significantly higher (19.5%) between-year variation in population sex ratio in multiple-queen eusocial species, which supports the view that in these species, sex ratio can also fluctuate in response to temporal changes in social factors such as queen number and queen-worker control over sex ratio, as well as factors influencing caste determination. The simultaneous adjustment of sex ratio in response to temporal fluctuations in ecological and social factors seems to preclude the existence of a single sex ratio optimum. The absence of such an optimum may reflect an additional cost associated with the evolution of complex breeding systems in Hymenoptera societies.

Evaluating the timeliness of reporting in a First Nations communicable diseases program

PubMed Central

Lam, A; Woods, S; Ndubuka, N

2017-01-01

Background Timely reporting of communicable diseases is necessary to enable a prompt response to mitigate and control outbreaks. This is especially true among First Nations communities due to a number of factors, including unique social determinants of health, which can contribute to rapid disease transmission. Objective To assess the timeliness of reporting for 12 notifiable communicable diseases in the Northern Inter-Tribal Health Authority, which includes 33 First Nations on-reserve communities in Northern Saskatchewan, Canada, and to assess whether there were differences in reporting times depending on degree of remoteness of community, season or year. Methods Data for four sexually transmitted infections (STIs) and eight other communicable diseases were abstracted from the integrated Public Health Information System (iPHIS) between 2008 and 2013 and compared against the targets set for reporting in the Saskatchewan Communicable Disease Control Manual. The reporting time was defined as the duration from client exposure or presentation at clinic to the case notification day at Saskatchewan’s Ministry of Health. Communicable diseases were evaluated for proportion of cases reported within recommended time, and mean reporting time. Geographical and reporting data were also recorded to assess variations in reporting time among different northern communities and according to season or year. Results A total of 9,767 records were identified for the 12 diseases; all had a 14-day recommended reporting time, with the exception of shigellosis, which had a three-day reporting time. Overall, 93.6% of the diseases were reported in the recommended reporting time, although there was variability among the diseases. All four of the STIs (chlamydia, gonococcal infections, HIV and syphilis) had over 90% of cases reported within the 14-day recommended time period. Other communicable diseases reporting times varied from a high of 93.4% for methicillin-resistant Staphylococcus aureus (MRSA), 91.7% for lab-confirmed influenza and 89.1% for streptococcal A-invasive disease to a low of 16.2% for shigellosis and 12.2% for pertussis. Salmonellosis and pneumococcal-invasive disease were intermediary with 77.4% and 72.2%, respectively. Mean reporting times indicated that eight of the 12 diseases (66.7%) had reporting times similar to or better than recommended times. There appeared to be a correlation between longer reporting periods and the more northern communities. There were no seasonal variations found but yearly-trend analysis demonstrated an anomalous year in 2011, in which all communicable diseases with the exception of STIs experienced a peak in reporting delays. Conclusion Overall, communicable disease reporting in this northern health authority program met recommended reporting times, although there were variations according to the disease, the area reporting and the year. Further research is needed to understand these variations in order to inform efforts to strengthen communicable disease surveillance among First Nations communities. PMID:29770078

ITKids part II: variation of postures and muscle activity in children using different information and communication technologies.

PubMed

Ciccarelli, Marina; Straker, Leon; Mathiassen, Svend Erik; Pollock, Clare

2011-01-01

There are concerns that insufficient variation in postural and muscle activity associated with use of modern information and communication technology (ICT) presents a risk for musculoskeletal ill-health among school children. However, scientific knowledge on physical exposure variation in this group is limited. The purpose of this study was to quantify postures and muscle activity of school children using different types of ICT. Postures of the head, upper back and upper arm, and muscle activity of the right and left upper trapezius and right forearm extensors were measured over 10-12 hours in nine school children using different types of ICT at school and away-from-school. Variation in postures and muscle activity was quantified using two indices, EVA{sd} and APDF₉₀-₁₀. Paper-based (Old) ICT tasks produced postures that were less neutral but more variable than electronics-based (New ICT) and Non-ICT tasks. Non-ICT tasks involved mean postures similar to New ICT tasks, but with greater variation. Variation of muscle activity was similar between ICT types in the right and left upper trapezius muscles. Non-ICT tasks produced more muscle activity variation in the right forearm extensor group compared to New and Old ICT tasks. Different ICT tasks produce different degrees of variation in posture and muscle activity. Combining tasks that use different ICT may increase overall exposure variation. More research is needed to determine what degree of postural and muscle activity variation is associated with reduced risk of musculoskeletal ill-health.

Assessment of State- and Territorial-Level Preparedness Capacity for Serving Deaf and Hard-of-Hearing Populations in Disasters

PubMed Central

Tseng, Winston; Dahrouge, Donna; Engelman, Alina; Neuhauser, Linda; Huang, Debbie; Gurung, Sidhanta

2014-01-01

Objectives Substantial evidence exists that emergency preparedness and response efforts are not effectively reaching populations with functional and access needs, especially barriers related to literacy, language, culture, or disabilities. More than 36 million Americans are Deaf or hard of hearing (Deaf/HH). These groups experienced higher risks of injury, death, and property loss in recent disasters than the general public. We conducted a participatory research study to examine national recommendations on preparedness communication for the Deaf/HH. Methods We assessed whether previous recommendations regarding the Deaf/HH have been incorporated into state- and territorial-level emergency operations plans (EOPs), interviewed state- and territorial-level preparedness directors about capacity to serve the Deaf/HH, and proposed strategies to benefit Deaf/HH populations during emergencies. We analyzed 55 EOPs and 50 key informant (KI) interviews with state directors. Results Fifty-five percent of EOPs mentioned vulnerable populations; however, only 31% specifically mentioned Deaf/HH populations in their plan. Study findings indicated significant relationships among the following factors: a state-level KI's familiarity with communication issues for the Deaf/HH, making relay calls (i.e., calls to services to relay communication between Deaf and hearing people), and whether the KI's department provides trainings about serving Deaf/HH populations in emergencies. We found significant associations between a state's percentage of Deaf/HH individuals and a KI's familiarity with Deaf/HH communication issues and provision by government of any disability services to Deaf/HH populations in emergencies. Further, we found significant relationships between KIs attending training on serving the Deaf/HH and familiarity with Deaf/HH communication issues, including how to make relay calls. Conclusion This study provides new knowledge that can help emergency agencies improve their preparedness training, planning, and capacity to serve Deaf/HH populations in emergencies. PMID:24587549

Landscape heterogeneity drives intra-population niche variation and reproduction in an arctic top predator

PubMed Central

L'Hérault, Vincent; Franke, Alastair; Lecomte, Nicolas; Alogut, Adam; Bêty, Joël

2013-01-01

While intra-population variability in resource use is ubiquitous, little is known of how this measure of niche diversity varies in space and its role in population dynamics. Here we examined how heterogeneous breeding environments can structure intra-population niche variation in both resource use and reproductive output. We investigated intra-population niche variation in the Arctic tundra ecosystem, studying peregrine falcon (Falco peregrinus tundrius, White) breeding within a terrestrial-marine gradient near Rankin Inlet, Nunavut, Canada. Using stable isotope analysis, we found that intra-population niches varied at the individual level; we examined within-nest and among-nest variation, though only the latter varied along the terrestrial-marine gradient (i.e., increased among-nest variability among birds nesting within the marine environment, indicating higher degree of specialization). Terrestrial prey species (small herbivores and insectivores) were consumed by virtually all falcons. Falcons nesting within the marine environment made use of marine prey (sea birds), but depended heavily on terrestrial prey (up to 90% of the diet). Using 28-years of peregrine falcon nesting data, we found a positive relationship between the proportion of terrestrial habitat surrounding nest sites and annual nestling production, but no relationship with the likelihood of successfully rearing at least one nestling reaching 25 days old. Annually, successful inland breeders raised 0.47 more young on average compared to offshore breeders, which yields potential fitness consequences for this long-living species. The analyses of niche and reproductive success suggest a potential breeding cost for accessing distant terrestrial prey, perhaps due to additional traveling costs, for those individuals with marine nest site locations. Our study indicates how landscape heterogeneity can generate proximate (niche variation) and ultimate (reproduction) consequences on a population of generalist predator. We also show that within-individual and among-individual variation are not mutually exclusive, but can simultaneously arise and structure intra-population niche variation. PMID:24101979

Predator cannibalism can intensify negative impacts on heterospecific prey.

PubMed

Takatsu, Kunio; Kishida, Osamu

2015-07-01

Although natural populations consist of individuals with different traits, and the degree of phenotypic variation varies among populations, the impact of phenotypic variation on ecological interactions has received little attention, because traditional approaches to community ecology assume homogeneity of individuals within a population. Stage structure, which is a common way of generating size and developmental variation within predator populations, can drive cannibalistic interactions, which can affect the strength of predatory effects on the predator's heterospecific prey. Studies have shown that predator cannibalism weakens predatory effects on heterospecific prey by reducing the size of the predator population and by inducing less feeding activity of noncannibal predators. We predict, however, that predator cannibalism, by promoting rapid growth of the cannibals, can also intensify predation pressure on heterospecific prey, because large predators have large resource requirements and may utilize a wider variety of prey species. To test this hypothesis, we conducted an experiment in which we created carnivorous salamander (Hynobius retardatus) populations with different stage structures by manipulating the salamander's hatch timing (i.e., populations with large or small variation in the timing of hatching), and explored the resultant impacts on the abundance, behavior, morphology, and life history of the salamander's large heterospecific prey, Rana pirica frog tadpoles. Cannibalism was rare in salamander populations having small hatch-timing variation, but was frequent in those having large hatch-timing variation. Thus, giant salamander cannibals occurred only in the latter. We clearly showed that salamander giants exerted strong predation pressure on frog tadpoles, which induced large behavioral and morphological defenses in the tadpoles and caused them to metamorphose late at large size. Hence, predator cannibalism arising from large variation in the timing of hatching can strengthen predatory effects on heterospecific prey and can have impacts on various, traits of both predator and prey. Because animals commonly broaden their diet as they grow, such negative impacts of predator cannibalism on the heterospecific prey may be common in interactions between predators and prey species of similar size.

Low Predictability of Colour Polymorphism in Introduced Guppy (Poecilia reticulata) Populations in Panama

PubMed Central

Martínez, Celestino; Chavarría, Carmen; Sharpe, Diana M. T.; De León, Luis Fernando

2016-01-01

Colour polymorphism is a recurrent feature of natural populations, and its maintenance has been studied in a range of taxa in their native ranges. However, less is known about whether (and how) colour polymorphism is maintained when populations are removed from their native environments, as in the case of introduced species. We here address this issue by analyzing variation in colour patterns in recently-discovered introduced populations of the guppy (Poecilia reticulata) in Panama. Specifically, we use classic colour analysis to estimate variation in the number and the relative area of different colour spots across low predation sites in the introduced Panamanian range of the species. We then compare this variation to that found in the native range of the species under low- and high predation regimes. We found aspects of the colour pattern that were both consistent and inconsistent with the classical paradigm of colour evolution in guppies. On one hand, the same colours that dominated in native populations (orange, iridescent and black) were also the most dominant in the introduced populations in Panama. On the other, there were no clear differences between either introduced-low and native low- and high predation populations. Our results are therefore only partially consistent with the traditional role of female preference in the absence of predators, and suggest that additional factors could influence colour patterns when populations are removed from their native environments. Future research on the interaction between female preference and environmental variability (e.g. multifarious selection), could help understand adaptive variation in this widely-introduced species, and the contexts under which variation in adaptive traits parallels (or not) variation in the native range. PMID:26863538

Low Predictability of Colour Polymorphism in Introduced Guppy (Poecilia reticulata) Populations in Panama.

PubMed

Martínez, Celestino; Chavarría, Carmen; Sharpe, Diana M T; De León, Luis Fernando

2016-01-01

Colour polymorphism is a recurrent feature of natural populations, and its maintenance has been studied in a range of taxa in their native ranges. However, less is known about whether (and how) colour polymorphism is maintained when populations are removed from their native environments, as in the case of introduced species. We here address this issue by analyzing variation in colour patterns in recently-discovered introduced populations of the guppy (Poecilia reticulata) in Panama. Specifically, we use classic colour analysis to estimate variation in the number and the relative area of different colour spots across low predation sites in the introduced Panamanian range of the species. We then compare this variation to that found in the native range of the species under low- and high predation regimes. We found aspects of the colour pattern that were both consistent and inconsistent with the classical paradigm of colour evolution in guppies. On one hand, the same colours that dominated in native populations (orange, iridescent and black) were also the most dominant in the introduced populations in Panama. On the other, there were no clear differences between either introduced-low and native low- and high predation populations. Our results are therefore only partially consistent with the traditional role of female preference in the absence of predators, and suggest that additional factors could influence colour patterns when populations are removed from their native environments. Future research on the interaction between female preference and environmental variability (e.g. multifarious selection), could help understand adaptive variation in this widely-introduced species, and the contexts under which variation in adaptive traits parallels (or not) variation in the native range.

Assessing intraspecific variation in effective dispersal along an altitudinal gradient: a test in two Mediterranean high-mountain plants.

PubMed

Lara-Romero, Carlos; Robledo-Arnuncio, Juan J; García-Fernández, Alfredo; Iriondo, Jose M

2014-01-01

Plant recruitment depends among other factors on environmental conditions and their variation at different spatial scales. Characterizing dispersal in contrasting environments may thus be necessary to understand natural intraspecific variation in the processes underlying recruitment. Silene ciliata and Armeria caespitosa are two representative species of cryophilic pastures above the tree line in Mediterranean high mountains. No explicit estimations of dispersal kernels have been made so far for these or other high-mountain plants. Such data could help to predict their dispersal and recruitment patterns in a context of changing environments under ongoing global warming. We used an inverse modelling approach to analyse effective seed dispersal patterns in five populations of both Silene ciliata and Armeria caespitosa along an altitudinal gradient in Sierra de Guadarrama (Madrid, Spain). We considered four commonly employed two-dimensional seedling dispersal kernels exponential-power, 2Dt, WALD and log-normal. No single kernel function provided the best fit across all populations, although estimated mean dispersal distances were short (<1 m) in all cases. S. ciliata did not exhibit significant among-population variation in mean dispersal distance, whereas significant differences in mean dispersal distance were found in A. caespitosa. Both S. ciliata and A. caespitosa exhibited among-population variation in the fecundity parameter and lacked significant variation in kernel shape. This study illustrates the complexity of intraspecific variation in the processes underlying recruitment, showing that effective dispersal kernels can remain relatively invariant across populations within particular species, even if there are strong variations in demographic structure and/or physical environment among populations, while the invariant dispersal assumption may not hold for other species in the same environment. Our results call for a case-by-case analysis in a wider range of plant taxa and environments to assess the prevalence and magnitude of intraspecific dispersal variation.

Epigenetic differentiation and relationship to adaptive genetic divergence in discrete populations of the violet Viola cazorlensis.

PubMed

Herrera, Carlos M; Bazaga, Pilar

2010-08-01

*In plants, epigenetic variations based on DNA methylation are often heritable and could influence the course of evolution. Before this hypothesis can be assessed, fundamental questions about epigenetic variation remain to be addressed in a real-world context, including its magnitude, structuring within and among natural populations, and autonomy in relation to the genetic context. *Extent and patterns of cytosine methylation, and the relationship to adaptive genetic divergence between populations, were investigated for wild populations of the southern Spanish violet Viola cazorlensis (Violaceae) using the methylation-sensitive amplified polymorphism (MSAP) technique, a modification of the amplified fragment length polymorphism method (AFLP) based on the differential sensitivity of isoschizomeric restriction enzymes to site-specific cytosine methylation. *The genome of V. cazorlensis plants exhibited extensive levels of methylation, and methylation-based epigenetic variation was structured into distinct between- and within- population components. Epigenetic differentiation of populations was correlated with adaptive genetic divergence revealed by a Bayesian population-genomic analysis of AFLP data. Significant associations existed at the individual genome level between adaptive AFLP loci and the methylation state of methylation-susceptible MSAP loci. *Population-specific, divergent patterns of correlated selection on epigenetic and genetic individual variation could account for the coordinated epigenetic-genetic adaptive population differentiation revealed by this study.

Balancing selection on the number of repeats in the ribosomal intergenic spacer present in naturally occurring yellow perch (Perca flavescens) populations.

PubMed

Bélanger-Lépine, Frédérique; Leung, Christelle; Glémet, Hélène; Angers, Bernard

2018-01-01

The ribosomal intergenic spacer (IGS), responsible for the rate of transcription of rRNA genes, is associated with the growth and fecundity of individuals. A previous study of IGS length variants in a yellow perch (Perca flavescens) population revealed the presence of two predominant alleles differing by 1 kb due to variation in the number of repeat units. This study aims to assess whether length variation of IGS is the result of selection in natural populations. Length variation of IGS and 11 neutral microsatellite loci were assessed in geographically distant yellow perch populations. Most populations displayed the very same IGS alleles; they did not differ in frequencies among populations and the F ST was not significantly different from zero. In contrast, diversity at microsatellite loci was high and differed among populations (F ST = 0.18). Selection test based on F ST identified IGS as a significant outlier from neutral expectations for population differentiation. Heterozygote excess was also detected in one specific cohort, suggesting temporal variation in the selection regime. While the exact mechanism remains to be specified, together the results of this study support the contention that balancing selection is acting to maintain two distinct IGS alleles in natural fish populations.

A Spatiotemporal Analysis of Extreme Heat Vulnerability Across the United States using Geospatial Techniques

NASA Astrophysics Data System (ADS)

Schoessow, F. S.; Li, Y.; Howe, P. D.

2016-12-01

Extreme heat events are the deadliest natural hazard in the United States and are expected to increase in both severity and frequency in the coming years due to the effects of climate change. The risks of climate change and weather-related events such as heat waves to a population can be more comprehensively assessed by coupling the traditional examination of natural hazards using remote sensing and geospatial analysis techniques with human vulnerability factors and individual perceptions of hazards. By analyzing remote-sensed and empirical survey data alongside national hazards advisories, this study endeavors to establish a nationally-representative baseline quantifying the spatiotemporal variation of individual heat vulnerabilities at multiple scales and between disparate population groups affected by their unique socioenvironmental factors. This is of immediate academic interest because the study of heat waves risk perceptions remains relatively unexplored - despite the intensification of extreme heat events. The use of "human sensors", georeferenced & timestamped individual response data, provides invaluable contextualized data at a high spatial resolution, which will enable policy-makers to more effectively implement targeted strategies for risk prevention, mitigation, and communication. As climate change risks are further defined, this cognizance will help identify vulnerable populations and enhance national hazard preparedness and recovery frameworks.

Demographic variation across successional stages and their effects on the population dynamics of the neotropical palm Euterpe precatoria.

PubMed

Otárola, Mauricio Fernández; Avalos, Gerardo

2014-06-01

• Premise of the study: Environmental heterogeneity is a strong selective force shaping adaptation and population dynamics across temporal and spatial scales. Natural and anthropogenic gradients influence the variation of environmental and biotic factors, which determine population demography and dynamics. Successional gradients are expected to influence demographic parameters, but the relationship between these gradients and the species life history, habitat requirements, and degree of variation in demographic traits remains elusive.• Methods: We used the palm Euterpe precatoria to test the effect of successional stage on plant demography within a continuous population. We calculated demographic parameters for size stages and performed matrix analyses to investigate the demographic variation within primary and secondary forests of La Selva, Costa Rica.• Key results: We observed differences in mortality and recruitment of small juveniles between primary and secondary forests. Matrix models described satisfactorily the chronosequence of population changes, which were characterized by high population growth rate in disturbed areas, and decreased growth rate in old successional forests until reaching stability.• Conclusions: Different demographic parameters can be expressed in contiguous subpopulations along a gradient of successional stages with important consequences for population dynamics. Demographic variation superimposed on these gradients contributes to generate subpopulations with different demographic composition, density, and ecological properties. Therefore, the effects of spatial variation must be reconsidered in the design of demographic analyses of tropical palms, which are prime examples of subtle local adaptation. These considerations are crucial in the implementation of management plans for palm species within spatially complex and heterogeneous tropical landscapes. © 2014 Botanical Society of America, Inc.

Transposable elements generate population-specific insertional patterns and allelic variation in genes of wild emmer wheat (Triticum turgidum ssp. dicoccoides).

PubMed

Domb, Katherine; Keidar, Danielle; Yaakov, Beery; Khasdan, Vadim; Kashkush, Khalil

2017-10-27

Natural populations of the tetraploid wild emmer wheat (genome AABB) were previously shown to demonstrate eco-geographically structured genetic and epigenetic diversity. Transposable elements (TEs) might make up a significant part of the genetic and epigenetic variation between individuals and populations because they comprise over 80% of the wild emmer wheat genome. In this study, we performed detailed analyses to assess the dynamics of transposable elements in 50 accessions of wild emmer wheat collected from 5 geographically isolated sites. The analyses included: the copy number variation of TEs among accessions in the five populations, population-unique insertional patterns, and the impact of population-unique/specific TE insertions on structure and expression of genes. We assessed the copy numbers of 12 TE families using real-time quantitative PCR, and found significant copy number variation (CNV) in the 50 wild emmer wheat accessions, in a population-specific manner. In some cases, the CNV difference reached up to 6-fold. However, the CNV was TE-specific, namely some TE families showed higher copy numbers in one or more populations, and other TE families showed lower copy numbers in the same population(s). Furthermore, we assessed the insertional patterns of 6 TE families using transposon display (TD), and observed significant population-specific insertional patterns. The polymorphism levels of TE-insertional patterns reached 92% among all wild emmer wheat accessions, in some cases. In addition, we observed population-specific/unique TE insertions, some of which were located within or close to protein-coding genes, creating allelic variations in a population-specific manner. We also showed that those genes are differentially expressed in wild emmer wheat. For the first time, this study shows that TEs proliferate in wild emmer wheat in a population-specific manner, creating new alleles of genes, which contribute to the divergent evolution of homeologous genes from the A and B subgenomes.

Internet and social media for health-related information and communication in health care: preferences of the Dutch general population.

PubMed

Van de Belt, Tom H; Engelen, Lucien J L P G; Berben, Sivera A A; Teerenstra, Steven; Samsom, Melvin; Schoonhoven, Lisette

2013-10-02

Health care is increasingly featured by the use of Web 2.0 communication and collaborative technologies that are reshaping the way patients and professionals interact. These technologies or tools can be used for a variety of purposes: to instantly debate issues, discover news, analyze research, network with peers, crowd-source information, seek support, and provide advice. Not all tools are implemented successfully; in many cases, the nonusage attrition rates are high. Little is known about the preferences of the Dutch general population regarding the use of the Internet and social media in health care. To determine the preferences of the general population in the Netherlands regarding the use of the Internet and social media in health care. A cross-sectional survey was disseminated via a popular Dutch online social network. Respondents were asked where they searched for health-related information, how they qualified the value of different sources, and their preferences regarding online communication with health care providers. Results were weighed for the Dutch population based on gender, age, and level of education using official statistics. Numbers and percentages or means and standard deviations were presented for different subgroups. One-way ANOVA was used to test for statistical differences. The survey was completed by 635 respondents. The Internet was found to be the number one source for health-related information (82.7%), closely followed by information provided by health care professionals (71.1%). Approximately one-third (32.3%) of the Dutch population search for ratings of health care providers. The most popular information topics were side effects of medication (62.5%) and symptoms (59.7%). Approximately one-quarter of the Dutch population prefer to communicate with a health care provider via social media (25.4%), and 21.2% would like to communicate via a webcam. The Internet is the main source of health-related information for the Dutch population. One in 4 persons wants to communicate with their physician via social media channels and it is expected that this number will further increase. Health care providers should explore new ways of communicating online and should facilitate ways for patients to connect with them. Future research should aim at comparing different patient groups and diseases, describing best practices, and determining cost-effectiveness.

Internet and Social Media For Health-Related Information and Communication in Health Care: Preferences of the Dutch General Population

PubMed Central

Engelen, Lucien JLPG; Berben, Sivera AA; Teerenstra, Steven; Samsom, Melvin; Schoonhoven, Lisette

2013-01-01

Background Health care is increasingly featured by the use of Web 2.0 communication and collaborative technologies that are reshaping the way patients and professionals interact. These technologies or tools can be used for a variety of purposes: to instantly debate issues, discover news, analyze research, network with peers, crowd-source information, seek support, and provide advice. Not all tools are implemented successfully; in many cases, the nonusage attrition rates are high. Little is known about the preferences of the Dutch general population regarding the use of the Internet and social media in health care. Objective To determine the preferences of the general population in the Netherlands regarding the use of the Internet and social media in health care. Methods A cross-sectional survey was disseminated via a popular Dutch online social network. Respondents were asked where they searched for health-related information, how they qualified the value of different sources, and their preferences regarding online communication with health care providers. Results were weighed for the Dutch population based on gender, age, and level of education using official statistics. Numbers and percentages or means and standard deviations were presented for different subgroups. One-way ANOVA was used to test for statistical differences. Results The survey was completed by 635 respondents. The Internet was found to be the number one source for health-related information (82.7%), closely followed by information provided by health care professionals (71.1%). Approximately one-third (32.3%) of the Dutch population search for ratings of health care providers. The most popular information topics were side effects of medication (62.5%) and symptoms (59.7%). Approximately one-quarter of the Dutch population prefer to communicate with a health care provider via social media (25.4%), and 21.2% would like to communicate via a webcam. Conclusions The Internet is the main source of health-related information for the Dutch population. One in 4 persons wants to communicate with their physician via social media channels and it is expected that this number will further increase. Health care providers should explore new ways of communicating online and should facilitate ways for patients to connect with them. Future research should aim at comparing different patient groups and diseases, describing best practices, and determining cost-effectiveness. PMID:24088272

Natural Genetic Variation and Candidate Genes for Morphological Traits in Drosophila melanogaster

PubMed Central

Carreira, Valeria Paula; Mensch, Julián; Hasson, Esteban; Fanara, Juan José

2016-01-01

Body size is a complex character associated to several fitness related traits that vary within and between species as a consequence of environmental and genetic factors. Latitudinal and altitudinal clines for different morphological traits have been described in several species of Drosophila and previous work identified genomic regions associated with such variation in D. melanogaster. However, the genetic factors that orchestrate morphological variation have been barely studied. Here, our main objective was to investigate genetic variation for different morphological traits associated to the second chromosome in natural populations of D. melanogaster along latitudinal and altitudinal gradients in Argentina. Our results revealed weak clinal signals and a strong population effect on morphological variation. Moreover, most pairwise comparisons between populations were significant. Our study also showed important within-population genetic variation, which must be associated to the second chromosome, as the lines are otherwise genetically identical. Next, we examined the contribution of different candidate genes to natural variation for these traits. We performed quantitative complementation tests using a battery of lines bearing mutated alleles at candidate genes located in the second chromosome and six second chromosome substitution lines derived from natural populations which exhibited divergent phenotypes. Results of complementation tests revealed that natural variation at all candidate genes studied, invected, Fasciclin 3, toucan, Reticulon-like1, jing and CG14478, affects the studied characters, suggesting that they are Quantitative Trait Genes for morphological traits. Finally, the phenotypic patterns observed suggest that different alleles of each gene might contribute to natural variation for morphological traits. However, non-additive effects cannot be ruled out, as wild-derived strains differ at myriads of second chromosome loci that may interact epistatically with mutant alleles. PMID:27459710

Variation in the ovine cortisol response to systemic bacterial endotoxin challenge is predominantly determined by signalling within the hypothalamic-pituitary-adrenal axis

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

You Qiumei; Karrow, Niel A.; Cao Honghe

Bi-directional communication between the neuroendocrine and immune systems is designed, in part, to maintain or restore homeostasis during physiological stress. Exposure to endotoxin during Gram-negative bacterial infection for example, elicits the release of pro-inflammatory cytokines that activate the hypothalamic-pituitary-adrenal axis (HPAA). The secretion of adrenal glucocorticoids subsequently down regulates the host inflammatory response, minimizing potential tissue damage. Sequence and epigenetic variants in genes involved in regulating the neuroendocrine and immune systems are likely to contribute to individual differences in the HPAA response, and this may influence the host anti-inflammatory response to toxin exposure and susceptibility to inflammatory disease. In thismore » study, high (HCR) and low (LCR) cortisol responders were selected from a normal population of 110 female sheep challenged iv with Escherichia coli endotoxin (400 ng/kg) to identify potential determinants that contribute to variation in the cortisol response phenotype. This phenotype was stable over several years in the HCR and LCR animals, and did not appear to be attributed to differences in expression of hepatic immune-related genes or systemic pro-inflammatory cytokine concentrations. Mechanistic studies using corticotrophin-releasing factor (0.5 {mu}g/kg body weight), arginine vasopressin (0.5 {mu}g/kg), and adrenocorticotropic hormone (0.5 {mu}g/kg) administered iv demonstrated that variation in this phenotype is largely determined by signalling within the HPAA. Future studies will use this ovine HCR/LCR model to investigate potential genetic and epigenetic variants that may contribute to variation in cortisol responsiveness to bacterial endotoxin.« less

Acoustic voice analysis of prelingually deaf adults before and after cochlear implantation.

PubMed

Evans, Maegan K; Deliyski, Dimitar D

2007-11-01

It is widely accepted that many severe to profoundly deaf adults have benefited from cochlear implants (CIs). However, limited research has been conducted to investigate changes in voice and speech of prelingually deaf adults who receive CIs, a population well known for presenting with a variety of voice and speech abnormalities. The purpose of this study was to use acoustic analysis to explore changes in voice and speech for three prelingually deaf males pre- and postimplantation over 6 months. The following measurements, some measured in varying contexts, were obtained: fundamental frequency (F0), jitter, shimmer, noise-to-harmonic ratio, voice turbulence index, soft phonation index, amplitude- and F0-variation, F0-range, speech rate, nasalance, and vowel production. Characteristics of vowel production were measured by determining the first formant (F1) and second formant (F2) of vowels in various contexts, magnitude of F2-variation, and rate of F2-variation. Perceptual measurements of pitch, pitch variability, loudness variability, speech rate, and intonation were obtained for comparison. Results are reported using descriptive statistics. The results showed patterns of change for some of the parameters while there was considerable variation across the subjects. All participants demonstrated a decrease in F0 in at least one context and demonstrated a change in nasalance toward the norm as compared to their normal hearing control. The two participants who were oral-language communicators were judged to produce vowels with an average of 97.2% accuracy and the sign-language user demonstrated low percent accuracy for vowel production.

Different effects of variation in Xanthium strumarium L. (Compositae) on two insect seed predators.

PubMed

Hare, J Daniel; Futuyma, Douglas J

1978-01-01

To determine the relative importance of variation in several plant characters on susceptibility to herbivores, we examined patterns of seed predation by two monophagous insect species and patterns of variation in ten populations of the cocklebur, Xanthium strumarium. Multiple regression analysis disclosed that one seed predator was most influenced by plant chemical variation, the other was significantly influenced by both chemical and morphological variation, but variation in yet another character, general burr size, was most important in conferring resistance to both insects simultaneously. The plant populations differed most in this character. Although many of the plant characters were correlated with each other, those important in determining susceptibility to each insect species were uncorrelated and independent of those conferring resistance to both insects simultaneously.These results imply that ecological similar herbivores may be influenced by different aspects of plant variation, and that predictions of evolutionary responses of local plant populations to herbivory may require knowledge of the structure of local herbivore communities and the dynamics of their establishment.

Extremely long posterior communicating artery diagnosed by MR angiography: report of two cases.

PubMed

Uchino, Akira; Suzuki, Chihiro; Tanaka, Masahiko

2015-07-01

We report two cases of an extremely long left posterior communicating artery (PCoA) diagnosed by magnetic resonance (MR) angiography. The PCoA arose from the normal point of the supraclinoid internal carotid artery and fused with the posterior cerebral artery (PCA) at its posterior ambient segment, forming an extremely long PCoA and extremely long precommunicating segment of the PCA. To our knowledge, this is the first report of such variation. Careful observation of MR angiographic images is important for detecting rare arterial variations. To identify these anomalous arteries on MR angiography, partial maximum-intensity-projection images are useful.

An evaluation of multiple-schedule variations to reduce high-rate requests in the picture exchange communication system.

PubMed

Landa, Robin; Hanley, Gregory P

2016-06-01

Using procedures similar to those of Tiger, Hanley, and Heal (2006), we compared two multiple-schedule variations (S+/S- and S+ only) to treat high-rate requests for edible items in the Picture Exchange Communication System (PECS). Two individuals with autism participated, after they showed persistent requests for edible items after PECS training. Stimulus control was achieved only with the multiple schedule that involved presentation of a discriminative stimulus during reinforcement components and its removal during extinction components (S+ only). Discriminated requests were maintained for the 1 participant who experienced schedule thinning. © 2016 Society for the Experimental Analysis of Behavior.

Genetic differentiation among populations of Pinus ponderosa from the upper Colorado River Basin

Treesearch

Gerald Rehfeldt

1990-01-01

Genetic variation among 62 populations of ponderosa pine was studied by comparing seedlings from all populations according to (1) growth and development of 4-yr-old seedlings in three disparate common gardens and (2) patterns of shoot elongation of 2-yr-old seedlings in a greenhouse. Genetic variation was detected among populations for 19 of the variables, most of...

Conserving genomic variability in large mammals: Effect of population fluctuations and variance in male reproductive success on variability in Yellowstone bison

Treesearch

Andres Perez-Figueroa; Rick L. Wallen; Tiago Antao; Jason A. Coombs; Michael K. Schwartz; P. J. White; Gordon Luikart

2012-01-01

Loss of genetic variation through genetic drift can reduce population viability. However, relatively little is known about loss of variation caused by the combination of fluctuating population size and variance in reproductive success in age structured populations. We built an individual-based computer simulation model to examine how actual culling and hunting...

Genetic mapping of variation in dauer larvae development in growing populations of Caenorhabditis elegans.

PubMed

Green, J W M; Snoek, L B; Kammenga, J E; Harvey, S C

2013-10-01

In the nematode Caenorhabditis elegans, the appropriate induction of dauer larvae development within growing populations is likely to be a primary determinant of genotypic fitness. The underlying genetic architecture of natural genetic variation in dauer formation has, however, not been thoroughly investigated. Here, we report extensive natural genetic variation in dauer larvae development within growing populations across multiple wild isolates. Moreover, bin mapping of introgression lines (ILs) derived from the genetically divergent isolates N2 and CB4856 reveals 10 quantitative trait loci (QTLs) affecting dauer formation. Comparison of individual ILs to N2 identifies an additional eight QTLs, and sequential IL analysis reveals six more QTLs. Our results also show that a behavioural, laboratory-derived, mutation controlled by the neuropeptide Y receptor homolog npr-1 can affect dauer larvae development in growing populations. These findings illustrate the complex genetic architecture of variation in dauer larvae formation in C. elegans and may help to understand how the control of variation in dauer larvae development has evolved.

Should the governments of 'developed' countries be held responsible for equalizing the indigenous health gap?

PubMed

Abdolhosseini, Parirash; Bonner, Chantel; Montano, Alexandra; Young, Yves-Yvette; Wadsworth, Daniel; Williams, Michelle; Stoner, Lee

2016-12-01

Across the globe there is significant variation between and within indigenous populations in terms of world view, culture, and socio-political forces. However, many indigenous groups do share a striking commonality: greater rates of non-communicable diseases and shorter life expectancies than non-indigenous compatriots. Notably, this health gap persists for 'developed' countries, including Australia, Canada, New Zealand and the United States. The question of who is responsible for equalizing the gap is complicated. Using Australia as an exemplar context, this commentary will present arguments 'for' and 'against' the governments of developed nations being held liable for closing the indigenous health gap. We will discuss the history and nature of the health gap, actions needed to 'close the gap', and which party has the necessary resources to do so. © The Author(s) 2015.

Variations in the branching pattern of posterior division of mandibular nerve: a case report.

PubMed

Muraleedharan, Aparna; Veeramani, Raveendranath; Chand, Parkash

2014-11-01

Abnormal communications among the branches of mandibular nerve especially the posterior division are significant due to various procedures undertaken in this region. These variations are worth reporting as they pose serious implications in several interventions in this region, and may even lead to false diagnosis. During routine dissection, the mandibular nerve and its branches were dissected in the infratemporal fossa. The branches from the posterior division of the mandibular nerve namely the inferior alveolar and auriculotemporal nerves were carefully dissected, and their abnormal branching pattern was noted. There was a communicating branch between left inferior alveolar and auriculotemporal nerve. There was also a variant recurrent branch from the left inferior alveolar nerve that supplied the lateral pterygoid muscle. Such variant branches and communications between the branches of mandibular nerve as seen in this case have an embryological basis and are clinically important in this region especially for dental surgeries and anesthesia.

Family-centered services for children with complex communication needs: the practices and beliefs of school-based speech-language pathologists.

PubMed

Mandak, Kelsey; Light, Janice

2018-06-01

This study used an online focus group to examine the beliefs and practices of school-based speech-language pathologists (SLPs) who served children with complex communication needs regarding their provision of family-centered services. Participants revealed that despite their desire for family involvement and reported beliefs in the importance of family-centered services, there were barriers in place that often limited family-centered service provision. Across the SLPs, many were dissatisfied with their current provision of family-centered services. The SLPs varied in their reported practices, with some reporting family-centered services and others, professional-centered services. Future research is recommended in order to investigate which factors contribute to the variation among SLPs and how the variation impacts children who require augmentative and alternative communication (AAC) and their families. Potential clinical implications for in-service and pre-service SLPs are discussed to improve future family-centered AAC services.

Effects of Genetic Drift and Gene Flow on the Selective Maintenance of Genetic Variation

PubMed Central

Star, Bastiaan; Spencer, Hamish G.

2013-01-01

Explanations for the genetic variation ubiquitous in natural populations are often classified by the population–genetic processes they emphasize: natural selection or mutation and genetic drift. Here we investigate models that incorporate all three processes in a spatially structured population, using what we call a construction approach, simulating finite populations under selection that are bombarded with a steady stream of novel mutations. As expected, the amount of genetic variation compared to previous models that ignored the stochastic effects of drift was reduced, especially for smaller populations and when spatial structure was most profound. By contrast, however, for higher levels of gene flow and larger population sizes, the amount of genetic variation found after many generations was greater than that in simulations without drift. This increased amount of genetic variation is due to the introduction of slightly deleterious alleles by genetic drift and this process is more efficient when migration load is higher. The incorporation of genetic drift also selects for fitness sets that exhibit allele-frequency equilibria with larger domains of attraction: they are “more stable.” Moreover, the finiteness of populations strongly influences levels of local adaptation, selection strength, and the proportion of allele-frequency vectors that can be distinguished from the neutral expectation. PMID:23457235

Food and fitness: associations between crop yields and life-history traits in a longitudinally monitored pre-industrial human population.

PubMed

Hayward, Adam D; Holopainen, Jari; Pettay, Jenni E; Lummaa, Virpi

2012-10-22

Severe food shortage is associated with increased mortality and reduced reproductive success in contemporary and historical human populations. Studies of wild animal populations have shown that subtle variation in environmental conditions can influence patterns of mortality, fecundity and natural selection, but the fitness implications of such subtle variation on human populations are unclear. Here, we use longitudinal data on local grain production, births, marriages and mortality so as to assess the impact of crop yield variation on individual age-specific mortality and fecundity in two pre-industrial Finnish populations. Although crop yields and fitness traits showed profound year-to-year variation across the 70-year study period, associations between crop yields and mortality or fecundity were generally weak. However, post-reproductive individuals of both sexes, and individuals of lower socio-economic status experienced higher mortality when crop yields were low. This is the first longitudinal, individual-based study of the associations between environmental variation and fitness traits in pre-industrial humans, which emphasizes the importance of a portfolio of mechanisms for coping with low food availability in such populations. The results are consistent with evolutionary ecological predictions that natural selection for resilience to food shortage is likely to weaken with age and be most severe on those with the fewest resources.

Chloroplast microsatellites reveal population genetic diversity in red pine, Pinus resinosa Ait

Treesearch

Craig S. Echt; L.L. DeVerno; M. Anzidei; G.G. Vendramin

1998-01-01

Variation in paternally inherited chloroplast microsatellite (cpSSR) DNA was used to study population genetic structure in red pine (Pinus resinosa Ait.), a species characterized by morphological uniformity, no allozyme variation, and limited RAPD variation. Using nine cpSSR loci, a total of 23 chloroplast haplotypes and 25 cpSSR alleles were were...

Spatial variation in the relationship between performance and metabolic rate in wild juvenile Atlantic salmon

Treesearch

Grethe Robertsen; John D. Armstrong; Keith H. Nislow; Ivar Herfindal; Simon McKelvey; Sigurd Einum; Martin Genner

2014-01-01

Maintenance of metabolic rate (MR, the energy cost of self-maintenance) is linked to behavioural traits and fitness and varies substantially within populations. Despite having received much attention, the causes and consequences of this variation remain obscure. Theoretically, such within-population variation in fitness-related traits can be maintained by environmental...

Burn Injuries and Their Impact on Cognitive-Communication Skills in the Inpatient Rehabilitation Setting.

PubMed

Hendricks, Carla Tierney; Camara, Kristin; Violick Boole, Kathryn; Napoli, Maureen F; Goldstein, Richard; Ryan, Colleen M; Schneider, Jeffrey C

The prevalence and extent of cognitive-communication disorders and factors that have impact on outcomes are examined in the burn population within an inpatient rehabilitation facility. A retrospective data analysis was conducted on adults diagnosed with burn injury (n = 144). Descriptive statistics were used to identify the prevalence of cognitive-communication deficits on admission and discharge. The main outcomes were cognitive-communication ratings on discharge from inpatient rehabilitation as measured by the memory and problem-solving domains of the Functional Independence Measure (FIM) and composite score of the Functional Communication Measure (FCM). Medical, demographic and rehabilitation predictors of the main outcomes were assessed using regression analyses. On admission to inpatient rehabilitation, 79% of the total population presented with cognitive-communication impairments, and of them, 27% presented with persistent deficits on discharge. Admission FIM memory score, marital status, and age were significant predictors of discharge FIM memory score. Admission FIM problem-solving score, age, marital status, and prehospital living-with were significant predictors of discharge FIM problem-solving score. Admission FCM score and age were significant predictors of discharge FCM cognitive score. Persons with burn injuries are at risk for cognitive-communication impairments, which may persist after inpatient rehabilitation. FIM data obtained on admission can be used as a screening tool to identify these at-risk patients. Future work is needed to assess the efficacy of speech-language pathologist intervention for cognitive-communication deficits within the burn injury population.

Ecological association between HIV and concurrency point-prevalence in South Africa's ethnic groups.

PubMed

Kenyon, Chris

2013-11-01

HIV prevalence between different ethnic groups within South Africa exhibits considerable variation. Numerous authors believe that elevated sexual partner concurrency rates are important in the spread of HIV. Few studies have, however, investigated if differential concurrency rates could explain differential HIV spread within ethnic groups in South Africa. This ecological analysis, explores how much of the variation in HIV prevalence by ethnic group is explained by differential concurrency rates. Using a nationally representative survey (the South African National HIV Prevalence, HIV Incidence, Behaviour and Communication Survey, 2005) the HIV prevalence in each of eight major ethnic groups was calculated. Linear regression analysis was used to assess the association between an ethnic group's HIV prevalence and the point-prevalence of concurrency. Results showed that HIV prevalence rates varied considerably between South Africa's ethnic groups. This applied to both different racial groups and to different ethnic groups within the black group. The point-prevalence of concurrency by ethnic group was strongly associated with HIV prevalence (R(2) = 0.83; p = 0.001). Tackling the key drivers of high HIV transmission in this population may benefit from more emphasis on partner reduction interventions.

Effect of Modality and Task Type on Interlanguage Variation

ERIC Educational Resources Information Center

Kim, Hye Yeong

2017-01-01

An essential component for assessing the accuracy and fluency of language learners is understanding how mode of communication and task type affect performance in second-language (L2) acquisition. This study investigates how text-based synchronous computer-mediated communication (SCMC) and face-to-face (F2F) oral interaction can influence the…

The Impact of Electronic Communication on Writing. ERIC Digest.

ERIC Educational Resources Information Center

Abdullah, Mardziah Hayati

Noting that electronic communication places new demands on language that leads to interesting variations in written language use, this Digest summarizes insights gained from research on writing behavior and performance in the electronic age. It concludes that both the process and the content of writing are evolving in response to the increased use…

Assessment and Management of the Communication Difficulties of Children with Cerebral Palsy: A UK Survey of SLT Practice

ERIC Educational Resources Information Center

Watson, Rose Mary; Pennington, Lindsay

2015-01-01

Background: Communication difficulties are common in cerebral palsy (CP) and are frequently associated with motor, intellectual and sensory impairments. Speech and language therapy research comprises single-case experimental design and small group studies, limiting evidence-based intervention and possibly exacerbating variation in practice. Aims:…

The Educational Nature of Different Ways Teachers Communicate with Children about Natural Phenomena

ERIC Educational Resources Information Center

Gustavsson, Laila; Pramling, Niklas

2014-01-01

This empirical study analyses the qualitatively different ways in which teachers approach children's learning in and about nature. The empirical data consists of video observations of children and teachers communicating with one another around natural phenomena found during excursions into a forest. Variation theory is presented as a framework for…

Increasing Communication Skills: A Case Study of a Man with Autism Spectrum Disorder and Vision Loss

ERIC Educational Resources Information Center

Kee, S. Brian; Casey, Laura Baylot; Cea, Clayton R.; Bicard, David F.; Bicard, Sara E.

2012-01-01

According to the "Diagnostic and Statistical Manual of Mental Disorders" (DSM-IV-TR; American Psychiatric Association, APA, 2000), autism is a neurodevelopmental disorder that is characterized by impairments in social and communicative behaviors with great variations in ability, depending on developmental level, intelligence, and chronological…

Variation is function: Are single cell differences functionally important?: Testing the hypothesis that single cell variation is required for aggregate function.

PubMed

Dueck, Hannah; Eberwine, James; Kim, Junhyong

2016-02-01

There is a growing appreciation of the extent of transcriptome variation across individual cells of the same cell type. While expression variation may be a byproduct of, for example, dynamic or homeostatic processes, here we consider whether single-cell molecular variation per se might be crucial for population-level function. Under this hypothesis, molecular variation indicates a diversity of hidden functional capacities within an ensemble of identical cells, and this functional diversity facilitates collective behavior that would be inaccessible to a homogenous population. In reviewing this topic, we explore possible functions that might be carried by a heterogeneous ensemble of cells; however, this question has proven difficult to test, both because methods to manipulate molecular variation are limited and because it is complicated to define, and measure, population-level function. We consider several possible methods to further pursue the hypothesis that variation is function through the use of comparative analysis and novel experimental techniques. © 2015 The Authors. BioEssays published by WILEY Periodicals, Inc.

Hybrid Mobile Communication Networks for Planetary Exploration

NASA Technical Reports Server (NTRS)

Alena, Richard; Lee, Charles; Walker, Edward; Osenfort, John; Stone, Thom

2007-01-01

A paper discusses the continuing work of the Mobile Exploration System Project, which has been performing studies toward the design of hybrid communication networks for future exploratory missions to remote planets. A typical network could include stationary radio transceivers on a remote planet, mobile radio transceivers carried by humans and robots on the planet, terrestrial units connected via the Internet to an interplanetary communication system, and radio relay transceivers aboard spacecraft in orbit about the planet. Prior studies have included tests on prototypes of these networks deployed in Arctic and desert regions chosen to approximate environmental conditions on Mars. Starting from the findings of the prior studies, the paper discusses methods of analysis, design, and testing of the hybrid communication networks. It identifies key radio-frequency (RF) and network engineering issues. Notable among these issues is the study of wireless LAN throughput loss due to repeater use, RF signal strength, and network latency variations. Another major issue is that of using RF-link analysis to ensure adequate link margin in the face of statistical variations in signal strengths.

MAINTENANCE OF ECOLOGICALLY SIGNIFICANT GENETIC VARIATION IN THE TIGER SWALLOWTAIL BUTTERFLY THROUGH DIFFERENTIAL SELECTION AND GENE FLOW.

PubMed

Bossart, J L; Scriber, J M

1995-12-01

Differential selection in a heterogeneous environment is thought to promote the maintenance of ecologically significant genetic variation. Variation is maintained when selection is counterbalanced by the homogenizing effects of gene flow and random mating. In this study, we examine the relative importance of differential selection and gene flow in maintaining genetic variation in Papilio glaucus. Differential selection on traits contributing to successful use of host plants (oviposition preference and larval performance) was assessed by comparing the responses of southern Ohio, north central Georgia, and southern Florida populations of P. glaucus to three hosts: Liriodendron tulipifera, Magnolia virginiana, and Prunus serotina. Gene flow among populations was estimated using allozyme frequencies from nine polymorphic loci. Significant genetic differentiation was observed among populations for both oviposition preference and larval performance. This differentiation was interpreted to be the result of selection acting on Florida P. glaucus for enhanced use of Magnolia, the prevalent host in Florida. In contrast, no evidence of population differentiation was revealed by allozyme frequencies. F ST -values were very small and Nm, an estimate of the relative strengths of gene flow and genetic drift, was large, indicating that genetic exchange among P. glaucus populations is relatively unrestricted. The contrasting patterns of spatial differentiation for host-use traits and lack of differentiation for electrophoretically detectable variation implies that differential selection among populations will be counterbalanced by gene flow, thereby maintaining genetic variation for host-use traits. © 1995 The Society for the Study of Evolution.

Genetic diversity and variation of Chinese fir from Fujian province and Taiwan, China, based on ISSR markers

PubMed Central

Chen, Yu; Peng, Zhuqing; Wu, Chao; Ma, Zhihui; Ding, Guochang; Cao, Guangqiu; Ruan, Shaoning; Lin, Sizu

2017-01-01

Genetic diversity and variation among 11 populations of Chinese fir from Fujian province and Taiwan were assessed using inter-simple sequence repeat (ISSR) markers to reveal the evolutionary relationship in their distribution range in this report. Analysis of genetic parameters of the different populations showed that populations in Fujian province exhibited a greater level of genetic diversity than did the populations in Taiwan. Compared to Taiwan populations, significant limited gene flow were observed among Fujian populations. An UPGMA cluster analysis showed that the most individuals of Taiwan populations formed a single cluster, whereas 6 discrete clusters were formed by each population from Fujian. All populations were divided into 3 main groups and that all 5 populations from Taiwan were gathered into a subgroup combined with 2 populations, Dehua and Liancheng, formed one of the 3 main groups, which indicated relative stronger relatedness. It is supported by a genetic structure analysis. All those results are suggesting different levels of genetic diversity and variation of Chinese fir between Fujian and Taiwan, and indicating different patterns of evolutionary process and local environmental adaption. PMID:28406956

Genetic diversity and variation of Chinese fir from Fujian province and Taiwan, China, based on ISSR markers.

PubMed

Chen, Yu; Peng, Zhuqing; Wu, Chao; Ma, Zhihui; Ding, Guochang; Cao, Guangqiu; Ruan, Shaoning; Lin, Sizu

2017-01-01

Genetic diversity and variation among 11 populations of Chinese fir from Fujian province and Taiwan were assessed using inter-simple sequence repeat (ISSR) markers to reveal the evolutionary relationship in their distribution range in this report. Analysis of genetic parameters of the different populations showed that populations in Fujian province exhibited a greater level of genetic diversity than did the populations in Taiwan. Compared to Taiwan populations, significant limited gene flow were observed among Fujian populations. An UPGMA cluster analysis showed that the most individuals of Taiwan populations formed a single cluster, whereas 6 discrete clusters were formed by each population from Fujian. All populations were divided into 3 main groups and that all 5 populations from Taiwan were gathered into a subgroup combined with 2 populations, Dehua and Liancheng, formed one of the 3 main groups, which indicated relative stronger relatedness. It is supported by a genetic structure analysis. All those results are suggesting different levels of genetic diversity and variation of Chinese fir between Fujian and Taiwan, and indicating different patterns of evolutionary process and local environmental adaption.

Conservation genetics of extremely isolated urban populations of the northern dusky salamander (Desmognathus fuscus) in New York City

PubMed Central

Zak, Yana; Pehek, Ellen

2013-01-01

Urbanization is a major cause of amphibian decline. Stream-dwelling plethodontid salamanders are particularly susceptible to urbanization due to declining water quality and hydrological changes, but few studies have examined these taxa in cities. The northern dusky salamander (Desmognathus fuscus) was once common in the New York City metropolitan area, but has substantially declined throughout the region in recent decades. We used five tetranucleotide microsatellite loci to examine population differentiation, genetic variation, and bottlenecks among five remnant urban populations of dusky salamanders in NYC. These genetic measures provide information on isolation, prevalence of inbreeding, long-term prospects for population persistence, and potential for evolutionary responses to future environmental change. All populations were genetically differentiated from each other, and the most isolated populations in Manhattan have maintained very little genetic variation (i.e. <20% heterozygosity). A majority of the populations also exhibited evidence of genetic bottlenecks. These findings contrast with published estimates of high genetic variation within and lack of structure between populations of other desmognathine salamanders sampled over similar or larger spatial scales. Declines in genetic variation likely resulted from population extirpations and the degradation of stream and terrestrial paths for dispersal in NYC. Loss of genetic variability in populations isolated by human development may be an underappreciated cause and/or consequence of the decline of this species in urbanized areas of the northeast USA. PMID:23646283

Genetic variation for resistance to ergot (Claviceps purpurea [Fr.] Tul.) among full-sib families of five populations of winter rye (Secale cereale L.).

PubMed

Mirdita, V; Dhillon, B S; Geiger, H H; Miedaner, T

2008-12-01

Ergot (Claviceps purpurea [Fr.] Tul.) is a serious disease of rye (Secale cereale L.) and it adversely affects the quality of grain. The present investigation was undertaken to study genotypic variability among full-sib families (FSF) of five open-pollinated (OP) winter rye populations of highly diverse origin, namely Dankovskie Selekcyine (Poland), Charkovskaja (Ukraine), NEM4 (Russia), Halo and Carokurz, both from Germany. About 50 FSF were developed at random in each population, and the FSF of each population were evaluated in separate but adjacent experiments conducted in four environments under artificial inoculation. A mixture of conidia of C. purpurea isolates was sprayed thrice during the flowering period. The materials were manually harvested at yellow-ripe stage. Resistance trait recorded was disease severity, i.e. percent ergot sclerotia in grain by weight. Mean ergot severity ranged from 2.29 to 4.08% for the five populations across environments. Significant genotypic variation (P < 0.01) due to FSF and FSF x environment interaction was observed within each population. Genotypic variation within all populations was higher than that among five populations. All populations showed high estimates of heritability (0.72-0.89). The study indicated that the evaluated OP populations are rich reservoirs of genetic variation that should also be used in hybrid breeding. Recurrent selection to further improve ergot resistance should be successful.

Discussing race-related limitations of genomic testing for colon cancer risk: implications for education and counseling.

PubMed

Butrick, Morgan N; Vanhusen, Lauren; Leventhal, Kara-Grace; Hooker, Gillian W; Nusbaum, Rachel; Peshkin, Beth N; Salehizadeh, Yasmin; Pavlick, Jessica; Schwartz, Marc D; Graves, Kristi D

2014-08-01

This study examines communication about limitations of genomic results interpretation for colon cancer risk during education and counseling of minority participants. As part of a larger study conducted from 2010 to 2012, participants recruited from a large primary care clinic were offered testing for a research panel of 3 genomic markers (single nucleotide polymorphisms or SNPs) for colorectal cancer risk. Genetic counselors conducted pre- and post-test sessions which included discussion of limitations of result interpretation due to the lack of racial/ethnic diversity in research populations from which risk data are derived. Sessions were audio-recorded, transcribed and thematically analyzed. Many participants did not respond directly to this limitation. Among the participants that responded directly to this race-related limitation, many responses were negative. However, a few participants connected the limited minority information about SNPs with the importance of their current research participation. Genetic counselor discussions of this limitation were biomedically focused with limited explanations for the lacking data. The communication process themes identified included: low immediacy (infrequent use of language directly involving a participant), verbal dominance (greater speaking ratio of the counselor to the patient) and wide variation in the degree of interactivity (or the amount of turn-taking during the discussion). Placed within the larger literature on patient-provider communication, these present results provide insight into the dynamics surrounding race-related educational content for genomic testing and other emerging technologies. Clinicians may be better able to engage patients in the use of new genomic technology by increasing their awareness of specific communication processes and patterns during education or counseling sessions. Copyright © 2014 Elsevier Ltd. All rights reserved.

Dynamics of newly established elk populations

USGS Publications Warehouse

Sargeant, G.A.; Oehler, M.W.

2007-01-01

The dynamics of newly established elk (Cervus elaphus) populations can provide insights about maximum sustainable rates of reproduction, survival, and increase. However, data used to estimate rates of increase typically have been limited to counts and rarely have included complementary estimates of vital rates. Complexities of population dynamics cannot be understood without considering population processes as well as population states. We estimated pregnancy rates, survival rates, age ratios, and sex ratios for reintroduced elk at Theodore Roosevelt National Park, North Dakota, USA; combined vital rates in a population projection model; and compared model projections with observed elk numbers and population ratios. Pregnancy rates in January (early in the second trimester of pregnancy) averaged 54.1% (SE = 5.4%) for subadults and 91.0% (SE = 1.7%) for adults, and 91.6% of pregnancies resulted in recruitment at 8 months. Annual survival rates of adult females averaged 0.96 (95% CI = 0.94-0.98) with hunting included and 0.99 (95% CI = 0.97-0.99) with hunting excluded from calculations. Our fitted model explained 99.8% of past variation in population estimates and represents a useful new tool for short-term management planning. Although we found no evidence of temporal variation in vital rates, variation in population composition caused substantial variation in projected rates of increase (??=1.20-1.36). Restoring documented hunter harvests and removals of elk by the National Park Service led to a potential rate of ?? = 1.26. Greater rates of increase substantiated elsewhere were within the expected range of chance variation, given our model and estimates of vital rates. Rates of increase realized by small elk populations are too variable to support inferences about habitat quality or density dependence.

Molecular phylogenetic analysis of Chinese indigenous blue-shelled chickens inferred from whole genomic region of the SLCO1B3 gene.

PubMed

Dalirsefat, Seyed Benyamin; Dong, Xianggui; Deng, Xuemei

2015-08-01

In total, 246 individuals from 8 Chinese indigenous blue- and brown-shelled chicken populations (Yimeng Blue, Wulong Blue, Lindian Blue, Dongxiang Blue, Lushi Blue, Jingmen Blue, Dongxiang Brown, and Lushi Brown) were genotyped for 21 SNP markers from the SLCO1B3 gene to evaluate phylogenetic relationships. As a representative of nonblue-shelled breeds, White Leghorn was included in the study for reference. A high proportion of SNP polymorphism was observed in Chinese chicken populations, ranging from 89% in Jingmen Blue to 100% in most populations, with a mean of 95% across all populations. The White Leghorn breed showed the lowest polymorphism, accounting for 43% of total SNPs. The mean expected heterozygosity varied from 0.11 in Dongxiang Blue to 0.46 in Yimeng Blue. Analysis of molecular variation (AMOVA) for 2 groups of Chinese chickens based on eggshell color type revealed 52% within-group and 43% between-group variations of the total genetic variation. As expected, FST and Reynolds' genetic distance were greatest between White Leghorn and Chinese chicken populations, with average values of 0.40 and 0.55, respectively. The first and second principal coordinates explained approximately 92% of the total variation and supported the clustering of the populations according to their eggshell color type and historical origins. STRUCTURE analysis showed a considerable source of variation among populations for the clustering into blue-shelled and nonblue-shelled chicken populations. The low estimation of genetic differentiation (FST) between Chinese chicken populations is possibly due to a common historical origin and high gene flow. Remarkably similar population classifications were obtained with all methods used in the study. Aligning endogenous avian retroviral (EAV)-HP insertion sequences showed no difference among the blue-shelled chickens. © 2015 Poultry Science Association Inc.

Genetics and the conservation of natural populations: allozymes to genomes.

PubMed

Allendorf, Fred W

2017-01-01

I consider how the study of genetic variation has influenced efforts to conserve natural populations over the last 50 years. Studies with allozymes in the 1970s provided the first estimates of the amount of genetic variation within and between natural populations at multiple loci. These early studies played an important role in developing plans to conserve species. The description of genetic variation in mitochondrial DNA in the early 1980s laid the foundation for the field of phylogeography, which provided a deeper look in time of the relationships and connectivity among populations. The development of microsatellites in the 1990s provided much more powerful means to describe genetic variation at nuclear loci, including the ability to detect past bottlenecks and estimate current effective population size with a single temporal sample. In the 2000s, single nucleotide polymorphisms presented a cornucopia of loci that has greatly improved power to estimate genetic and population demographic parameters important for conservation. Today, population genomics presents the ability to detect regions of the genome that are affected by natural selection (e.g. local adaptation or inbreeding depression). In addition, the ability to genotype historical samples has provided power to understand how climate change and other anthropogenic phenomena have affected populations. Modern molecular techniques provide unprecedented power to understand genetic variation in natural populations. Nevertheless, application of this information requires sound understanding of population genetics theory. I believe that current training in conservation genetics focuses too much on the latest techniques and too little on understanding the conceptual basis which is needed to interpret these data and ask good questions. © 2016 John Wiley & Sons Ltd.

Promoting Conditional Use of Communication Skills for Learners With Complex Communication Needs: A Tutorial.

PubMed

Simacek, Jessica; Reichle, Joe; Byiers, Breanne J; Parker-McGowan, Quannah; Dimian, Adele F; Elmquist, Marianne

2018-05-03

Conditional use of communication skills refers to the ability of a learner to appropriately generalize and discriminate when, where, and how to communicate based on constant variation and shifts in environmental cues. We describe discrimination and generalization challenges encountered by learners with complex communication needs and ways in which these challenges are fostered through traditional communication intervention programming. We address arrangements in instruction that maximize the probability of learners acquiring the conditional use of new vocabulary and the modest instructional technology implemented when planning for generalization. We propose establishing well-discriminated and generalized use of new vocabulary items through the application of a general case instruction framework to communication intervention programming. We provide intervention methodology, including intervention steps for general case instruction, a plethora of functional examples, and graphic displays to assess and intervene to promote conditional use of communication skills for learners with complex communication needs.

New Regions of the Human Genome Linked to Skin Color Variation in Some African Populations

Cancer.gov

In the first study of its kind, an international team of genomics researchers has identified new regions of the human genome that are associated with skin color variation in some African populations, opening new avenues for research on skin diseases and cancer in all populations.

Family losses following truncation selection in populations of half-sib families

Treesearch

J. H. Roberds; G. Namkoong; H. Kang

1980-01-01

Family losses during truncation selection may be sizable in populations of half-sib families. Substantial losses may occur even in populations containing little or no variation among families. Heavier losses will occur, however, under conditions of high heritability where there is considerable family variation. Standard deviations and therefore variances of family loss...

Associations between media use and health information-seeking behavior on vaccinations in South Korea.

PubMed

Kim, Jiyeon; Jung, Minsoo

2017-09-11

Although vaccinations are critical for preventing emerging infectious diseases, scant research has been conducted on risk communication. With socio-economic characteristics, health behavior, and underlying diseases under control, we investigated associations between media use, health information-seeking behavior, health information type, and vaccination in the population. This study relied on a national survey of Korean adults (n = 1367). Participants were adult males and females age 20 and older. Web and face-to-face surveys were conducted throughout July 2014. The main outcome was vaccination (categorized as yes or no). Independent variables were time spent on media, frequency of health information-seeking behavior, and types of health information sought. Controlling for co-variates, logistic regression analysis was conducted to identify factors that influence Korean adults being vaccinated. Results revealed that accessible information about emerging infectious diseases, listening to the radio, and reading the newspaper were associated with increased odds of being vaccinated. Active seeking health information as well as being female and of higher socio-economic status were positively correlated with Korean adults being vaccinated. It is critical to promote health information-seeking behavior and use diverse media channels to increase acceptance and awareness of emerging infectious diseases and vaccinations. Because there are differences in vaccination awareness depending on social class, it is critical to reduce communication inequality, strengthen accessibility to vaccinations, and devise appropriate risk communication strategies that ensure Korean adults receive vaccinations.

Isolation and genetic diversity of endangered grey nurse shark (Carcharias taurus) populations.

PubMed

Stow, Adam; Zenger, Kyall; Briscoe, David; Gillings, Michael; Peddemors, Victor; Otway, Nicholas; Harcourt, Robert

2006-06-22

Anthropogenic impacts are believed to be the primary threats to the eastern Australian population of grey nurse sharks (Carcharias taurus), which is listed as critically endangered, and the most threatened population globally. Analyses of 235 polymorphic amplified fragment length polymorphisms (AFLP) loci and 700 base pairs of mitochondrial DNA control region provide the first account of genetic variation and geographical partitioning (east and west coasts of Australia, South Africa) in C. taurus. Assignment tests, analysis of relatedness and Fst values all indicate that the Australian populations are isolated from South Africa, with negligible migration between the east and west Australian coasts. There are significant differences in levels of genetic variation among regions. Australian C. taurus, particularly the eastern population, has significantly less AFLP variation than the other sampling localities. Further, the eastern Australian sharks possess only a single mitochondrial haplotype, also suggesting a small number of founding individuals. Therefore, historical, rather than anthropogenic processes most likely account for their depauperate genetic variation. These findings have implications for the viability of the eastern Australian population of grey nurse sharks.

Singapore Genome Variation Project: a haplotype map of three Southeast Asian populations.

PubMed

Teo, Yik-Ying; Sim, Xueling; Ong, Rick T H; Tan, Adrian K S; Chen, Jieming; Tantoso, Erwin; Small, Kerrin S; Ku, Chee-Seng; Lee, Edmund J D; Seielstad, Mark; Chia, Kee-Seng

2009-11-01

The Singapore Genome Variation Project (SGVP) provides a publicly available resource of 1.6 million single nucleotide polymorphisms (SNPs) genotyped in 268 individuals from the Chinese, Malay, and Indian population groups in Southeast Asia. This online database catalogs information and summaries on genotype and phased haplotype data, including allele frequencies, assessment of linkage disequilibrium (LD), and recombination rates in a format similar to the International HapMap Project. Here, we introduce this resource and describe the analysis of human genomic variation upon agglomerating data from the HapMap and the Human Genome Diversity Project, providing useful insights into the population structure of the three major population groups in Asia. In addition, this resource also surveyed across the genome for variation in regional patterns of LD between the HapMap and SGVP populations, and for signatures of positive natural selection using two well-established metrics: iHS and XP-EHH. The raw and processed genetic data, together with all population genetic summaries, are publicly available for download and browsing through a web browser modeled with the Generic Genome Browser.

Singapore Genome Variation Project: A haplotype map of three Southeast Asian populations

PubMed Central

Teo, Yik-Ying; Sim, Xueling; Ong, Rick T.H.; Tan, Adrian K.S.; Chen, Jieming; Tantoso, Erwin; Small, Kerrin S.; Ku, Chee-Seng; Lee, Edmund J.D.; Seielstad, Mark; Chia, Kee-Seng

2009-01-01

The Singapore Genome Variation Project (SGVP) provides a publicly available resource of 1.6 million single nucleotide polymorphisms (SNPs) genotyped in 268 individuals from the Chinese, Malay, and Indian population groups in Southeast Asia. This online database catalogs information and summaries on genotype and phased haplotype data, including allele frequencies, assessment of linkage disequilibrium (LD), and recombination rates in a format similar to the International HapMap Project. Here, we introduce this resource and describe the analysis of human genomic variation upon agglomerating data from the HapMap and the Human Genome Diversity Project, providing useful insights into the population structure of the three major population groups in Asia. In addition, this resource also surveyed across the genome for variation in regional patterns of LD between the HapMap and SGVP populations, and for signatures of positive natural selection using two well-established metrics: iHS and XP-EHH. The raw and processed genetic data, together with all population genetic summaries, are publicly available for download and browsing through a web browser modeled with the Generic Genome Browser. PMID:19700652

Stellar metallicity variations across spiral arms in disk galaxies with multiple populations

NASA Astrophysics Data System (ADS)

Khoperskov, S.; Di Matteo, P.; Haywood, M.; Combes, F.

2018-03-01

This Letter studies the formation of azimuthal metallicity variations in the disks of spiral galaxies in the absence of initial radial metallicity gradients. Using high-resolution N-body simulations, we model composite stellar discs, made of kinematically cold and hot stellar populations, and study their response to spiral arm perturbations. We find that, as expected, disk populations with different kinematics respond differently to a spiral perturbation, with the tendency for dynamically cooler populations to show a larger fractional contribution to spiral arms than dynamically hotter populations. By assuming a relation between kinematics and metallicity, namely the hotter the population, the more metal-poor it is, this differential response to the spiral arm perturbations naturally leads to azimuthal variations in the mean metallicity of stars in the simulated disk. Thus, azimuthal variations in the mean metallicity of stars across a spiral galaxy are not necessarily a consequence of the reshaping, by radial migration, of an initial radial metallicity gradient. They indeed arise naturally also in stellar disks which have initially only a negative vertical metallicity gradient.

Geographic variation in the response of Culex pipiens life history traits to temperature.

PubMed

Ruybal, Jordan E; Kramer, Laura D; Kilpatrick, A Marm

2016-02-29

Climate change is predicted to alter the transmission of many vector-borne pathogens. The quantitative impact of climate change is usually estimated by measuring the temperature-performance relationships for a single population of vectors, and then mapping this relationship across a range of temperatures or locations. However, life history traits of different populations often differ significantly. Specifically, performance across a range of temperatures is likely to vary due to local adaptation to temperature and other factors. This variation can cause spatial variation in pathogen transmission and will influence the impact of climate change on the transmission of vector-borne pathogens. We quantified variation in life history traits for four populations of Culex pipiens (Linnaeus) mosquitoes. The populations were distributed along altitudinal and latitudinal gradients in the eastern United States that spanned ~3 °C in mean summer temperature, which is similar to the magnitude of global warming expected in the next 3-5 decades. We measured larval and adult survival, development rate, and biting rate at six temperatures between 16 and 35 °C, in a common garden experiment. Temperature had strong and consistent non-linear effects on all four life history traits for all four populations. Adult female development time decreased monotonically with increasing temperature, with the largest decrease at cold temperatures. Daily juvenile and adult female survival also decreased with increasing temperature, but the largest decrease occurred at higher temperatures. There was significant among-population variation in the thermal response curves for the four life history traits across the four populations, with larval survival, adult survival, and development rate varying up to 45, 79, and 84 % among populations, respectively. However, variation was not correlated with local temperatures and thus did not support the local thermal adaptation hypothesis. These results suggest that the impact of climate change on vector-borne disease will be more variable than previous predictions, and our data provide an estimate of this uncertainty. In addition, the variation among populations that we observed will shape the response of vectors to changing climates.

Genetic evidence supports song learning in the three-wattled bellbird Procnias tricarunculata (Cotingidae).

PubMed

Saranathan, Vinodkumar; Hamilton, Deborah; Powell, George V N; Kroodsma, Donald E; Prum, Richard O

2007-09-01

Vocal learning is thought to have evolved in three clades of birds (parrots, hummingbirds, and oscine passerines), and three clades of mammals (whales, bats, and primates). Behavioural data indicate that, unlike other suboscine passerines, the three-wattled bellbird Procnias tricarunculata (Cotingidae) is capable of vocal learning. Procnias tricarunculata shows conspicuous vocal ontogeny, striking geographical variation in song, and rapid temporal change in song within a population. Deprivation studies of vocal development in P. tricarunculata are impractical. Here, we report evidence from mitochondrial DNA sequences and nuclear microsatellite loci that genetic variation within and among the four allopatric breeding populations of P. tricarunculata is not congruent with variation in vocal behaviour. Sequences of the mitochondrial DNA control region document extensive haplotype sharing among localities and song types, and no phylogenetic resolution of geographical populations or behavioural groups. The vocally differentiated, allopatric breeding populations of P. tricarunculata are only weakly genetically differentiated populations, and are not distinct taxa. Mitochondrial DNA and microsatellite variation show small (2.9% and 13.5%, respectively) but significant correlation with geographical distance, but no significant residual variation by song type. Estimates of the strength of selection that would be needed to maintain the observed geographical pattern in vocal differentiation if songs were genetically based are unreasonably high, further discrediting the hypothesis of a genetic origin of vocal variation. These data support a fourth, phylogenetically independent origin of avian vocal learning in Procnias. Geographical variations in P. tricarunculata vocal behaviour are likely culturally evolved dialects.

Some Aspects of Communicable and Non-Communicable Diseases in Pacific Island Countries

ERIC Educational Resources Information Center

Gani, Azmat

2009-01-01

This study provides an overview of the incidence of the communicable and non-communicable diseases in Pacific Island countries. Available health statistics confirms that children continue to die annually due to neonatal causes, diarrhoeal diseases, pneumonia and measles. The adult population in several countries reveals presence and emergence of…

[Genetic structure of Hemibarbus labeo and Hemibarbus medius in South China based on mtDNA COI and ND5 genes].

PubMed

Lan, Zhao Jun; Lin, Long Feng; Zhao, Jun

2017-04-18

Both Hemibarbus labeo and H. medius (Cypriniformes: Cyprinidae: Gobioninae) are primary freshwater fishes and are widely distributed. As such, they provide an ideal model for phylogeographical studies. However, the similarity in morphological characters between these two species made the description of their distributions and the validation of species quite challenging. Here we employed variations in the DNA sequences of mitochondrial COI and ND5 genes (2151 bp) to solve this challenge and to study the population genetics structure of these two species. Among the 130 specimens belonging to 8 populations of H. labeo and 9 populations of H. medius from 17 drainage systems in southern China,196 variable sites (9.1% in the full sequences) falling into 50 haplotypes were identified. The haplotype diversity (h) and the nucleotide diversity (π) were 0.964 and 0.019, respectively, indicating a high level of genetic diversity and an evolutionary potential in both species. The result of neighbor-joining tree based on composite nucleotide sequences of the mtDNA COI and ND5 genes showed that the H. labeo and H. medius fell into two major clades (clade1and clade2): clade1was composed of some specimens of Oujiang River, all the specimens of Hanjiang River and Jiulongjiang River, whereas all remaining populations fell in clade2. The genetic distance between clade I and clade II was 0.036, while that between H. labeo and H. medius was 0.027. The haplotype network analyses indicated that the populations of Hanjiang River and Jiulongjiang River had relatively high genetic variation with the rest rivers. The po-pulations of Hainan Island migrated northward to Moyangjaing River. Haplotypes of the rivers of Hainan Island and Moyangjang River had relatively higher genetic variation with the Yangtze River than Pearl River. The populations of Xiangjiang River had no genetic variation with the populations of Guijiang River and Liujiang River. Analysis of molecular variance (AMOVA) indicated that the genetic variance mainly presented in individuals between geographical regions. The genetic variation of populations among regions was 71.2%, the genetic variation among populations within regions was 16.6%, and that within populations within the regions was 12.2%, indicating that most of the genetic variations resided in the populations among regions. The results of mismatch distribution and tests of neutrality suggested that in all populations, H. labeo, H. medius, clade1and clade2 were relatively stable.

Population-genetic properties of differentiated copy number variations in cattle.

PubMed

Xu, Lingyang; Hou, Yali; Bickhart, Derek M; Zhou, Yang; Hay, El Hamidi Abdel; Song, Jiuzhou; Sonstegard, Tad S; Van Tassell, Curtis P; Liu, George E

2016-03-23

While single nucleotide polymorphism (SNP) is typically the variant of choice for population genetics, copy number variation (CNV) which comprises insertion, deletion and duplication of genomic sequence, is an informative type of genetic variation. CNVs have been shown to be both common in mammals and important for understanding the relationship between genotype and phenotype. However, CNV differentiation, selection and its population genetic properties are not well understood across diverse populations. We performed a population genetics survey based on CNVs derived from the BovineHD SNP array data of eight distinct cattle breeds. We generated high resolution results that show geographical patterns of variations and genome-wide admixture proportions within and among breeds. Similar to the previous SNP-based studies, our CNV-based results displayed a strong correlation of population structure and geographical location. By conducting three pairwise comparisons among European taurine, African taurine, and indicine groups, we further identified 78 unique CNV regions that were highly differentiated, some of which might be due to selection. These CNV regions overlapped with genes involved in traits related to parasite resistance, immunity response, body size, fertility, and milk production. Our results characterize CNV diversity among cattle populations and provide a list of lineage-differentiated CNVs.

Low Variation in the Polymorphic Clock Gene Poly-Q Region Despite Population Genetic Structure across Barn Swallow (Hirundo rustica) Populations

PubMed Central

Dor, Roi; Lovette, Irby J.; Safran, Rebecca J.; Billerman, Shawn M.; Huber, Gernot H.; Vortman, Yoni; Lotem, Arnon; McGowan, Andrew; Evans, Matthew R.; Cooper, Caren B.; Winkler, David W.

2011-01-01

Recent studies of several species have reported a latitudinal cline in the circadian clock gene, Clock, which influences rhythms in both physiology and behavior. Latitudinal variation in this gene may hence reflect local adaptation to seasonal variation. In some bird populations, there is also an among-individual association between Clock poly-Q genotype and clutch initiation date and incubation period. We examined Clock poly-Q allele variation in the Barn Swallow (Hirundo rustica), a species with a cosmopolitan geographic distribution and considerable variation in life-history traits that may be influenced by the circadian clock. We genotyped Barn Swallows from five populations (from three subspecies) and compared variation at the Clock locus to that at microsatellite loci and mitochondrial DNA (mtDNA). We found very low variation in the Clock poly-Q region, as >96% of individuals were homozygous, and the two other alleles at this locus were globally rare. Genetic differentiation based on the Clock poly-Q locus was not correlated with genetic differentiation based on either microsatellite loci or mtDNA sequences. Our results show that high diversity in Clock poly-Q is not general across avian species. The low Clock variation in the background of heterogeneity in microsatellite and mtDNA loci in Barn Swallows may be an outcome of stabilizing selection on the Clock locus. PMID:22216124

Tolerance and potential for adaptation of a Baltic Sea rockweed under predicted climate change conditions.

PubMed

Rugiu, Luca; Manninen, Iita; Rothäusler, Eva; Jormalainen, Veijo

2018-03-01

Climate change is threating species' persistence worldwide. To predict species responses to climate change we need information not just on their environmental tolerance but also on its adaptive potential. We tested how the foundation species of rocky littoral habitats, Fucus vesiculosus, responds to combined hyposalinity and warming projected to the Baltic Sea by 2070-2099. We quantified responses of replicated populations originating from the entrance, central, and marginal Baltic regions. Using replicated individuals, we tested for the presence of within-population tolerance variation. Future conditions hampered growth and survival of the central and marginal populations whereas the entrance populations fared well. Further, both the among- and within-population variation in responses to climate change indicated existence of genetic variation in tolerance. Such standing genetic variation provides the raw material necessary for adaptation to a changing environment, which may eventually ensure the persistence of the species in the inner Baltic Sea. Copyright © 2017 Elsevier Ltd. All rights reserved.

An examination of relations between participation, communication and age in children with complex communication needs.

PubMed

Clarke, Michael; Newton, Caroline; Petrides, Konstantinos; Griffiths, Tom; Lysley, Andrew; Price, Katie

2012-03-01

The aim of this study was to examine variation in the frequency of children's participation in out-of-school activities as a function of speech intelligibility, perceived effectiveness of the child's communication aid, and age. Sixty-nine caregivers of children with complex communication needs provided with communication aids completed a questionnaire survey. Rate of participation was higher for younger than for older children, particularly in recreational activities. Younger children with partial intelligibility participated more frequently in recreational and social activities than both younger children without speech and older children. Results and limitations are discussed within the context of participation research in childhood disability, highlighting the impact of communicative resources and maturation on everyday participation.

Frequencies of Null Alleles at Enzyme Loci in Natural Populations of Ponderosa and Red Pine

PubMed Central

Allendorf, Fred W.; Knudsen, Kathy L.; Blake, George M.

1982-01-01

Pinus ponderosa and P. resinosa population samples have mean frequencies of enzymatically inactive alleles of 0.0031 and 0.0028 at 29 and 27 enzyme loci, respectively. Such alleles are rare and are apparently maintained by selection-mutation balance. Ponderosa pine have much higher amounts of allozymic and polygenic phenotypic variation than red pine, yet both species have similar frequencies of null alleles. Thus, null alleles apparently do not contribute to polygenic variation, as has been suggested. The concordance between allozymic and polygenic variation adds support to the view that allozyme studies may be valuable in predicting the relative amount of polygenic variation in populations. PMID:17246067

Spatial variation in pollinator-mediated selection on phenology, floral display and spur length in the orchid Gymnadenia conopsea.

PubMed

Chapurlat, Elodie; Ågren, Jon; Sletvold, Nina

2015-12-01

Spatial variation in plant-pollinator interactions may cause variation in pollinator-mediated selection on floral traits, but to establish this link conclusively experimental studies are needed. We quantified pollinator-mediated selection on flowering phenology and morphology in four populations of the fragrant orchid Gymnadenia conopsea, and compared selection mediated by diurnal and nocturnal pollinators in two of the populations. Variation in pollinator-mediated selection explained most of the among-population variation in the strength of directional and correlational selection. Pollinators mediated correlational selection on pairs of display traits, and on one display trait and spur length, a trait affecting pollination efficiency. Only nocturnal pollinators selected for longer spurs, and mediated stronger selection on the number of flowers compared with diurnal pollinators in one population. The two types of pollinators caused correlational selection on different pairs of traits and selected for different combinations of spur length and number of flowers. The results demonstrate that spatial variation in interactions with pollinators may result in differences in directional and correlational selection on floral traits in a plant with a semi-generalized pollination system, and suggest that differences in the relative importance of diurnal and nocturnal pollinators can cause variation in selection. © 2015 The Authors. New Phytologist © 2015 New Phytologist Trust.

Intra-specific variation in genome size in maize: cytological and phenotypic correlates

PubMed Central

Realini, María Florencia; Poggio, Lidia; Cámara-Hernández, Julián; González, Graciela Esther

2016-01-01

Genome size variation accompanies the diversification and evolution of many plant species. Relationships between DNA amount and phenotypic and cytological characteristics form the basis of most hypotheses that ascribe a biological role to genome size. The goal of the present research was to investigate the intra-specific variation in the DNA content in maize populations from Northeastern Argentina and further explore the relationship between genome size and the phenotypic traits seed weight and length of the vegetative cycle. Moreover, cytological parameters such as the percentage of heterochromatin as well as the number, position and sequence composition of knobs were analysed and their relationships with 2C DNA values were explored. The populations analysed presented significant differences in 2C DNA amount, from 4.62 to 6.29 pg, representing 36.15 % of the inter-populational variation. Moreover, intra-populational genome size variation was found, varying from 1.08 to 1.63-fold. The variation in the percentage of knob heterochromatin as well as in the number, chromosome position and sequence composition of the knobs was detected among and within the populations. Although a positive relationship between genome size and the percentage of heterochromatin was observed, a significant correlation was not found. This confirms that other non-coding repetitive DNA sequences are contributing to the genome size variation. A positive relationship between DNA amount and the seed weight has been reported in a large number of species, this relationship was not found in the populations studied here. The length of the vegetative cycle showed a positive correlation with the percentage of heterochromatin. This result allowed attributing an adaptive effect to heterochromatin since the length of this cycle would be optimized via selection for an appropriate percentage of heterochromatin. PMID:26644343

Genetic Variation in the Acorn Barnacle from Allozymes to Population Genomics

PubMed Central

Flight, Patrick A.; Rand, David M.

2012-01-01

Understanding the patterns of genetic variation within and among populations is a central problem in population and evolutionary genetics. We examine this question in the acorn barnacle, Semibalanus balanoides, in which the allozyme loci Mpi and Gpi have been implicated in balancing selection due to varying selective pressures at different spatial scales. We review the patterns of genetic variation at the Mpi locus, compare this to levels of population differentiation at mtDNA and microsatellites, and place these data in the context of genome-wide variation from high-throughput sequencing of population samples spanning the North Atlantic. Despite considerable geographic variation in the patterns of selection at the Mpi allozyme, this locus shows rather low levels of population differentiation at ecological and trans-oceanic scales (FST ∼ 5%). Pooled population sequencing was performed on samples from Rhode Island (RI), Maine (ME), and Southwold, England (UK). Analysis of more than 650 million reads identified approximately 335,000 high-quality SNPs in 19 million base pairs of the S. balanoides genome. Much variation is shared across the Atlantic, but there are significant examples of strong population differentiation among samples from RI, ME, and UK. An FST outlier screen of more than 22,000 contigs provided a genome-wide context for interpretation of earlier studies on allozymes, mtDNA, and microsatellites. FST values for allozymes, mtDNA and microsatellites are close to the genome-wide average for random SNPs, with the exception of the trans-Atlantic FST for mtDNA. The majority of FST outliers were unique between individual pairs of populations, but some genes show shared patterns of excess differentiation. These data indicate that gene flow is high, that selection is strong on a subset of genes, and that a variety of genes are experiencing diversifying selection at large spatial scales. This survey of polymorphism in S. balanoides provides a number of genomic tools that promise to make this a powerful model for ecological genomics of the rocky intertidal. PMID:22767487

Intraspecific divergence in sperm morphology of the green sea urchin, Strongylocentrotus droebachiensis: implications for selection in broadcast spawners

PubMed Central

2008-01-01

Background Sperm morphology can be highly variable among species, but less is known about patterns of population differentiation within species. Most studies of sperm morphometric variation are done in species with internal fertilization, where sexual selection can be mediated by complex mating behavior and the environment of the female reproductive tract. Far less is known about patterns of sperm evolution in broadcast spawners, where reproductive dynamics are largely carried out at the gametic level. We investigated variation in sperm morphology of a broadcast spawner, the green sea urchin (Strongylocentrotus droebachiensis), within and among spawnings of an individual, among individuals within a population, and among populations. We also examined population-level variation between two reproductive seasons for one population. We then compared among-population quantitative genetic divergence (QST) for sperm characters to divergence at neutral microsatellite markers (FST). Results All sperm traits except total length showed strong patterns of high diversity among populations, as did overall sperm morphology quantified using multivariate analysis. We also found significant differences in almost all traits among individuals in all populations. Head length, axoneme length, and total length had high within-male repeatability across multiple spawnings. Only sperm head width had significant within-population variation across two reproductive seasons. We found signatures of directional selection on head length and head width, with strong selection possibly acting on head length between the Pacific and West Atlantic populations. We also discuss the strengths and limitations of the QST-FST comparison. Conclusion Sperm morphology in S. droebachiensis is highly variable, both among populations and among individuals within populations, and has low variation within an individual across multiple spawnings. Selective pressures acting among populations may differ from those acting within, with directional selection implicated in driving divergence among populations and balancing selection as a possible mechanism for producing variability among males. Sexual selection in broadcast spawners may be mediated by different processes from those acting on internal fertilizers. Selective divergence in sperm head length among populations is associated with ecological differences among populations that may play a large role in mediating sexual selection in this broadcast spawner. PMID:18851755

Changing practice: implications of the World Report on Disability for responding to communication disability in under-served populations.

PubMed

Wylie, Karen; McAllister, Lindy; Davidson, Bronwyn; Marshall, Julie

2013-02-01

The World Report on Disability provides a major challenge to the conceptualization and delivery of services for people with communication disabilities around the world. Many people, in both Majority and Minority World countries, receive limited or no support in relation to their communication disability. In this paper the prevalence of communication disability across the world (and the challenges to obtaining these data) are discussed, particularly in relation to disability more broadly. Populations that are under-served by speech-language pathology services in both Majority and Minority World countries are described. The paper describes organizational change theory and the potential it has, together with a biopsychosocial model of disability, to assist in understanding and influencing development of relevant services for people with communication disabilities (PWCD), particularly those who are under-served. Aspects of, and influences on, service delivery for PWCD are described. The need for novel ways of conceptualizing development of services, including population-based approaches, is highlighted. Finally, the challenges and opportunities for PWCD and for speech-language pathologists which arise from the nine recommendations of the World Report on Disability are considered and readers are encouraged to consider new and novel ways of developing equitable services for people with communication disabilities, in both majority and minority world settings.

Low Genetic Variation of Red-Crowned Cranes on Hokkaido Island, Japan, Over the Hundred Years.

PubMed

Akiyama, Takuya; Momose, Kunikazu; Onuma, Manabu; Matsumoto, Fumio; Masuda, Ryuichi

2017-06-01

The red-crowned crane (Grus japonensis) is recognized internationally as an endangered species. Migratory populations breed in eastern Russia and northeastern China, whereas the resident population inhabits the island of Hokkaido, Japan. Although the population inhabiting Hokkaido had experienced a severe bottleneck by the end of the 19th century, the population size has recovered to about 1500 and continues to increase now thanks to conservation efforts. A previous study reported that no marked genetic differences were seen in the island population, and that the genetic variation of the whole population on Hokkaido was lower than that of the continental population. However, the precise genetic structure of the island population in the past or near present remains unclear. To better understand the spatiotemporal changes in the genetic structure of the island population, we performed mitochondrial DNA (mtDNA) analyses using stuffed specimens (years 1878-2001) and tissue or blood samples (years 1970-2014). We found three haplotypes in the island population, one of which was a novel mtDNA haplotype in 1997 and 2007 samples. In addition, there was no clear difference in the haplotype frequency through the time span. These results suggest that the low genetic variation of the island population persisted for the last hundred years. It is thus nearly impossible for the island population to recover its genetic variation in isolation. Conservation plans for this species should therefore include the promotion of genetic exchanges between the continental and island populations, such as through artificial introduction to Hokkaido.

Oral infection of Aedes aegypti with yellow fever virus: geographic variation and genetic considerations.

PubMed

Tabachnick, W J; Wallis, G P; Aitken, T H; Miller, B R; Amato, G D; Lorenz, L; Powell, J R; Beaty, B J

1985-11-01

Twenty-eight populations representing a worldwide distribution of Aedes aegypti were tested for their ability to become orally infected with yellow fever virus (YFV). Populations had been analyzed for genetic variations at 11 isozyme loci and assigned to one of 8 genetic geographic groups of Ae. aegypti. Infection rates suggest that populations showing isozyme genetic relatedness also demonstrate similarity to oral infection rates with YFV. The findings support the hypothesis that genetic variation exists for oral susceptibility to YFV in Ae. aegypti.

Geographic isolation drives divergence of uncorrelated genetic and song variation in the Ruddy-capped Nightingale-Thrush (Catharus frantzii; Aves: Turdidae).

PubMed

Ortiz-Ramírez, Marco F; Andersen, Michael J; Zaldívar-Riverón, Alejandro; Ornelas, Juan Francisco; Navarro-Sigüenza, Adolfo G

2016-01-01

Montane barriers influence the evolutionary history of lineages by promoting isolation of populations. The effects of these historical processes are evident in patterns of differentiation among extant populations, which are often expressed as genetic and behavioral variation between populations. We investigated the effects of geographic barriers on the evolutionary history of a Mesoamerican bird by studying patterns of genetic and vocal variation in the Ruddy-capped Nightingale-Thrush (Turdidae: Catharus frantzii), a non-migratory oscine bird that inhabits montane forests from central Mexico to Panama. We reconstructed the phylogeographic history and estimated divergence times between populations using Bayesian and maximum likelihood methods. We found strong support for the existence of four mitochondrial lineages of C. frantzii corresponding to isolated mountain ranges: Sierra Madre Oriental; Sierra Madre del Sur; the highlands of Chiapas, Guatemala, and El Salvador; and the Talamanca Cordillera. Vocal features in C. frantzii were highly variable among the four observed clades, but vocal variation and genetic variation were uncorrelated. Song variation in C. frantzii suggests that sexual selection and cultural drift could be important factors driving song differentiation in C. frantzii. Copyright © 2015 Elsevier Inc. All rights reserved.

Spatiotemporal variation in reproductive parameters of yellow-bellied marmots.

PubMed

Ozgul, Arpat; Oli, Madan K; Olson, Lucretia E; Blumstein, Daniel T; Armitage, Kenneth B

2007-11-01

Spatiotemporal variation in reproductive rates is a common phenomenon in many wildlife populations, but the population dynamic consequences of spatial and temporal variability in different components of reproduction remain poorly understood. We used 43 years (1962-2004) of data from 17 locations and a capture-mark-recapture (CMR) modeling framework to investigate the spatiotemporal variation in reproductive parameters of yellow-bellied marmots (Marmota flaviventris), and its influence on the realized population growth rate. Specifically, we estimated and modeled breeding probabilities of two-year-old females (earliest age of first reproduction), >2-year-old females that have not reproduced before (subadults), and >2-year-old females that have reproduced before (adults), as well as the litter sizes of two-year old and >2-year-old females. Most reproductive parameters exhibited spatial and/or temporal variation. However, reproductive parameters differed with respect to their relative influence on the realized population growth rate (lambda). Litter size had a stronger influence than did breeding probabilities on both spatial and temporal variations in lambda. Our analysis indicated that lambda was proportionately more sensitive to survival than recruitment. However, the annual fluctuation in litter size, abetted by the breeding probabilities, accounted for most of the temporal variation in lambda.

Determining the drivers of population structure in a highly urbanized landscape to inform conservation planning.

PubMed

Thomassen, Henri A; Harrigan, Ryan J; Semple Delaney, Kathleen; Riley, Seth P D; Serieys, Laurel E K; Pease, Katherine; Wayne, Robert K; Smith, Thomas B

2018-02-01

Understanding the environmental contributors to population structure is of paramount importance for conservation in urbanized environments. We used spatially explicit models to determine genetic population structure under current and future environmental conditions across a highly fragmented, human-dominated environment in Southern California to assess the effects of natural ecological variation and urbanization. We focused on 7 common species with diverse habitat requirements, home-range sizes, and dispersal abilities. We quantified the relative roles of potential barriers, including natural environmental characteristics and an anthropogenic barrier created by a major highway, in shaping genetic variation. The ability to predict genetic variation in our models differed among species: 11-81% of intraspecific genetic variation was explained by environmental variables. Although an anthropogenically induced barrier (a major highway) severely restricted gene flow and movement at broad scales for some species, genetic variation seemed to be primarily driven by natural environmental heterogeneity at a local level. Our results show how assessing environmentally associated variation for multiple species under current and future climate conditions can help identify priority regions for maximizing population persistence under environmental change in urbanized regions. © 2017 Society for Conservation Biology.

[Direccion General de Comunicacion. Programa Nacional de Comunicacion en Poblacion].

PubMed

1988-06-01

Peru's National Population Council is currently developing a national program of population communication. The program will be coordinated with public and private sector activities and will seek help from international organizations. The objective of the program is to promote changes in population knowledge, attitudes, and behaviors in priority social sectors and general public opinion to achieve a better harmony between population growth and distribution and socioeconomic development. The program strategy is to begin with identification of priority audiences. Other components of the strategy include quality control, coordination, decentralization, participation, use of low-cost technologies with high impact, and a multidisciplinary focus. An inventory of institutional activities in population communication will be a major activity.

Development of a model forecasting Dermanyssus gallinae's population dynamics for advancing Integrated Pest Management in laying hen facilities.

PubMed

Mul, Monique F; van Riel, Johan W; Roy, Lise; Zoons, Johan; André, Geert; George, David R; Meerburg, Bastiaan G; Dicke, Marcel; van Mourik, Simon; Groot Koerkamp, Peter W G

2017-10-15

The poultry red mite, Dermanyssus gallinae, is the most significant pest of egg laying hens in many parts of the world. Control of D. gallinae could be greatly improved with advanced Integrated Pest Management (IPM) for D. gallinae in laying hen facilities. The development of a model forecasting the pests' population dynamics in laying hen facilities without and post-treatment will contribute to this advanced IPM and could consequently improve implementation of IPM by farmers. The current work describes the development and demonstration of a model which can follow and forecast the population dynamics of D. gallinae in laying hen facilities given the variation of the population growth of D. gallinae within and between flocks. This high variation could partly be explained by house temperature, flock age, treatment, and hen house. The total population growth variation within and between flocks, however, was in part explained by temporal variation. For a substantial part this variation was unexplained. A dynamic adaptive model (DAP) was consequently developed, as models of this type are able to handle such temporal variations. The developed DAP model can forecast the population dynamics of D. gallinae, requiring only current flock population monitoring data, temperature data and information of the dates of any D. gallinae treatment. Importantly, the DAP model forecasted treatment effects, while compensating for location and time specific interactions, handling the variability of these parameters. The characteristics of this DAP model, and its compatibility with different mite monitoring methods, represent progression from existing approaches for forecasting D. gallinae that could contribute to advancing improved Integrated Pest Management (IPM) for D. gallinae in laying hen facilities. Copyright © 2017 Elsevier B.V. All rights reserved.

The genetic effect of copy number variations on the risk of alcoholism in a Korean population.

PubMed

Bae, Joon Seol; Jung, Myung Hun; Lee, Boung Chul; Cheong, Hyun Sub; Park, Byung Lae; Kim, Lyoung Hyo; Kim, Jeong-Hyun; Pasaje, Charisse Flerida A; Lee, Jin Sol; Jung, Kyoung Hwa; Chai, Young Gyu; Shin, Hyoung Doo; Choi, Ihn-Geun

2012-01-01

Alcoholism, a chronic behavioral disorder characterized by excessive alcohol consumption, has been a leading cause of morbidity and premature death. This condition is believed to be influenced by genetic factors. As copy number variation (CNV) has been recently discovered in human genome, genomic diversity of human genome is more frequent than previously thought. Many studies have reported evidences that CNV is associated with the development of complex diseases. In this study, we hypothesized that CNV can predict the risk of alcoholism. Using the Illumina HumanHap660W-Quad BeadChip (∼660 k markers), genome-wide genotyping was performed to obtain signal and allelic intensities from 116 alcoholic cases and 1,022 healthy controls (total n = 1,138) in a Korean population. To identify alcoholism-associated CNV regions, we performed a genome-wide association analysis, using multivariate logistic regression model controlling for age and gender. We identified a total of 255,732 individual CNVs and 3,261 CNV regions (1,067 common CNV regions, frequency > 1%) in this study. Results from multivariate logistic regression showed that the chr20:61195302-61195978 regions were significantly associated with the risk of alcoholism after multiple corrections (p = 5.02E-05, p(corr) = 0.04). Most of the identified variations in this study overlapped with the previously reported CNVs in the Database of Genomic Variants (95.3%). The identified CNVs, which encompassed 3,226 functional genes, were significantly enriched in the cellular part, in the membrane-bound organelle, in the cell part, in developmental processes, in cell communication, in neurological system process, in sensory perception of smell and chemical stimulus, and in olfactory receptor activity. This is the first genome-wide association study to investigate the relationship between common CNV and alcoholism. Our results suggest that the newly identified CNV regions may contribute to the development of alcoholism. Copyright © 2011 by the Research Society on Alcoholism.

Feed-Forward Propagation of Temporal and Rate Information between Cortical Populations during Coherent Activation in Engineered In Vitro Networks.

PubMed

DeMarse, Thomas B; Pan, Liangbin; Alagapan, Sankaraleengam; Brewer, Gregory J; Wheeler, Bruce C

2016-01-01

Transient propagation of information across neuronal assembles is thought to underlie many cognitive processes. However, the nature of the neural code that is embedded within these transmissions remains uncertain. Much of our understanding of how information is transmitted among these assemblies has been derived from computational models. While these models have been instrumental in understanding these processes they often make simplifying assumptions about the biophysical properties of neurons that may influence the nature and properties expressed. To address this issue we created an in vitro analog of a feed-forward network composed of two small populations (also referred to as assemblies or layers) of living dissociated rat cortical neurons. The populations were separated by, and communicated through, a microelectromechanical systems (MEMS) device containing a strip of microscale tunnels. Delayed culturing of one population in the first layer followed by the second a few days later induced the unidirectional growth of axons through the microtunnels resulting in a primarily feed-forward communication between these two small neural populations. In this study we systematically manipulated the number of tunnels that connected each layer and hence, the number of axons providing communication between those populations. We then assess the effect of reducing the number of tunnels has upon the properties of between-layer communication capacity and fidelity of neural transmission among spike trains transmitted across and within layers. We show evidence based on Victor-Purpura's and van Rossum's spike train similarity metrics supporting the presence of both rate and temporal information embedded within these transmissions whose fidelity increased during communication both between and within layers when the number of tunnels are increased. We also provide evidence reinforcing the role of synchronized activity upon transmission fidelity during the spontaneous synchronized network burst events that propagated between layers and highlight the potential applications of these MEMs devices as a tool for further investigation of structure and functional dynamics among neural populations.

Feed-Forward Propagation of Temporal and Rate Information between Cortical Populations during Coherent Activation in Engineered In Vitro Networks

PubMed Central

DeMarse, Thomas B.; Pan, Liangbin; Alagapan, Sankaraleengam; Brewer, Gregory J.; Wheeler, Bruce C.

2016-01-01

Transient propagation of information across neuronal assembles is thought to underlie many cognitive processes. However, the nature of the neural code that is embedded within these transmissions remains uncertain. Much of our understanding of how information is transmitted among these assemblies has been derived from computational models. While these models have been instrumental in understanding these processes they often make simplifying assumptions about the biophysical properties of neurons that may influence the nature and properties expressed. To address this issue we created an in vitro analog of a feed-forward network composed of two small populations (also referred to as assemblies or layers) of living dissociated rat cortical neurons. The populations were separated by, and communicated through, a microelectromechanical systems (MEMS) device containing a strip of microscale tunnels. Delayed culturing of one population in the first layer followed by the second a few days later induced the unidirectional growth of axons through the microtunnels resulting in a primarily feed-forward communication between these two small neural populations. In this study we systematically manipulated the number of tunnels that connected each layer and hence, the number of axons providing communication between those populations. We then assess the effect of reducing the number of tunnels has upon the properties of between-layer communication capacity and fidelity of neural transmission among spike trains transmitted across and within layers. We show evidence based on Victor-Purpura’s and van Rossum’s spike train similarity metrics supporting the presence of both rate and temporal information embedded within these transmissions whose fidelity increased during communication both between and within layers when the number of tunnels are increased. We also provide evidence reinforcing the role of synchronized activity upon transmission fidelity during the spontaneous synchronized network burst events that propagated between layers and highlight the potential applications of these MEMs devices as a tool for further investigation of structure and functional dynamics among neural populations. PMID:27147977

Blood Mercury Levels of Zebra Finches Are Heritable: Implications for the Evolution of Mercury Resistance

PubMed Central

Buck, Kenton A.; Varian-Ramos, Claire W.; Cristol, Daniel A.; Swaddle, John P.

2016-01-01

Mercury is a ubiquitous metal contaminant that negatively impacts reproduction of wildlife and has many other sub-lethal effects. Songbirds are sensitive bioindicators of mercury toxicity and may suffer population declines as a result of mercury pollution. Current predictions of mercury accumulation and biomagnification often overlook possible genetic variation in mercury uptake and elimination within species and the potential for evolution in affected populations. We conducted a study of dietary mercury exposure in a model songbird species, maintaining a breeding population of zebra finches (Taeniopygia guttata) on standardized diets ranging from 0.0–2.4 μg/g methylmercury. We applied a quantitative genetics approach to examine patterns of variation and heritability of mercury accumulation within dietary treatments using a method of mixed effects modeling known as the 'animal model'. Significant variation in blood mercury accumulation existed within each treatment for birds exposed at the same dietary level; moreover, this variation was highly repeatable for individuals. We observed substantial genetic variation in blood mercury accumulation for birds exposed at intermediate dietary concentrations. Taken together, this is evidence that genetic variation for factors affecting blood mercury accumulation could be acted on by selection. If similar heritability for mercury accumulation exists in wild populations, selection could result in genetic differentiation for populations in contaminated locations, with possible consequences for mercury biomagnification in food webs. PMID:27668745

Variation in probability of first reproduction of Weddell seals.

PubMed

Hadley, Gillian L; Rotella, Jay J; Garrott, Robert A; Nichols, James D

2006-09-01

1. For many species, when to begin reproduction is an important life-history decision that varies by individual and can have substantial implications for lifetime reproductive success and fitness. 2. We estimated age-specific probabilities of first-time breeding and modelled variation in these rates to determine age at first reproduction and understand why it varies in a population of Weddell seals in Erebus Bay, Antarctica. We used multistate mark-recapture modelling methods and encounter histories of 4965 known-age female seals to test predictions about age-related variation in probability of first reproduction and the effects of annual variation, cohort and population density. 3. Mean age at first reproduction in this southerly located study population (7.62 years of age, SD=1.71) was greater than age at first reproduction for a Weddell seal population at a more northerly and typical latitude for breeding Weddell seals (mean=4-5 years of age). This difference suggests that age at first reproduction may be influenced by whether a population inhabits the core or periphery of its range. 4. Age at first reproduction varied from 4 to 14 years, but there was no age by which all seals recruited to the breeding population, suggesting that individual heterogeneity exists among females in this population. 5. In the best model, the probability of breeding for the first time varied by age and year, and the amount of annual variation varied with age (average variance ratio for age-specific rates=4.3%). 6. Our results affirmed the predictions of life-history theory that age at first reproduction in long-lived mammals will be sensitive to environmental variation. In terms of life-history evolution, this variability suggests that Weddell seals display flexibility in age at first reproduction in order to maximize reproductive output under varying environmental conditions. Future analyses will attempt to test predictions regarding relationships between environmental covariates and annual variation in age at first reproduction and evaluate the relationship between age at first reproduction and lifetime reproductive success.

Genetic variation between populations of the stable fly, Stomoxys calcitrans (L.)(Diptera: Muscidae) from Nebraska, Denmark and Australia

USDA-ARS?s Scientific Manuscript database

The stable fly, Stomoxys calcitrans L., is a cosmopolitan, major pest of livestock. Previous studies on this insect, from samples within the United States, suggested a large amount of gene flow; more genetic variation was detected within populations than between populations. To compare the genetic v...

Altitudinal genetic variation among Pinus oocarpa populations in Michoacan, Mexico: implications for seed zoning, conservation, tree breeding and global warming

Treesearch

Cuauhtemoc Saenz-Romero; R. Ricardo Guzman-Reyna; Gerald E. Rehfeldt

2006-01-01

Pinus oocarpa has a large natural distribution in the sub-tropical forests of Mexico. Populations, however, are rapidly disappearing particularly in the Michoacan State as native forests are converted to avocado (Persea sp.) orchards.We investigated the patterning of genetic variation among P. oocarpa populations...

Population diversity and evidence of introgression among the black oaks of California

Treesearch

Richard S. Dodd; Nasser Kashani; Zara Afzal-Rafii

2002-01-01

The black oaks of California include 4 tree species (California black oak, coast live oak, Shreve oak, interior live oak) that are known to hybridize. Complex patterns of population variation within each species are likely to result from these hybrid combinations and from subsequent introgressions. We have been studying population variation using biochemical and...

Landscape location affects genetic variation of Canada lynx (Lynx canadensis)

Treesearch

M. K. Schwartz; L. S. Mills; Y. Ortega; L. F. Ruggiero; F. W. Allendorf

2003-01-01

The effect of a population's location on the landscape on genetic variation has been of interest to population genetics for more than half a century. However, most studies do not consider broadscale biogeography when interpreting genetic data. In this study, we propose an operational definition of a peripheral population, and then explore whether peripheral...

GENETIC STRUCTURE OF NORWAY SPRUCE (PICEA ABIES): CONCORDANCE OF MORPHOLOGICAL AND ALLOZYMIC VARIATION.

PubMed

Lagercrantz, Ulf; Ryman, Nils

1990-02-01

This study describes the population structure of Norway spruce (Picea abies) as revealed by protein polymorphisms and morphological variation. Electrophoretically detectable genetic variability was examined at 22 protein loci in 70 populations from the natural range of the species in Europe. Like other conifers, Norway spruce exhibits a relatively large amount of genetic variability and little differentiation among populations. Sixteen polymorphic loci (73%) segregate for a total of 51 alleles, and average heterozygosity per population is 0.115. Approximately 5% of the total genetic diversity is explained by differences between populations (G ST = 0.052), and Nei's standard genetic distance is less than 0.04 in all cases. We suggest that the population structure largely reflects relatively recent historical events related to the last glaciation and that Norway spruce is still in a process of adaptation and differentiation. There is a clear geographic pattern in the variation of allele frequencies. A major part of the allelefrequency variation can be accounted for by a few synthetic variables (principal components), and 80% of the variation of the first principal component is "explained" by latitude and longitude. The central European populations are consistently depauperate of genetic variability, most likely as an effect of severe restrictions of population size during the last glaciation. The pattern of differentiation at protein loci is very similar to that observed for seven morphological traits examined. This similarity suggests that the same evolutionary forces have acted upon both sets of characters. © 1990 The Society for the Study of Evolution.

Improvement of Effective Communication--The Case of Subtraction

ERIC Educational Resources Information Center

Olteanu, Constanta; Olteanu, Lucian

2012-01-01

The research study this article is based on aims to implement research knowledge to teaching, that is, the concept of critical aspects and dimensions of variation used in the variation theory. To do this, the researchers worked with willing teachers to explore how to make mathematics teaching more effective. This paper illustrates how teachers…

Stakeholders' Perceptions of Language Variation, English Language Teaching and Language Use: The Case of Hong Kong

ERIC Educational Resources Information Center

Chan, Jim Yee Him

2017-01-01

This study examines Hong Kong major stakeholders' (secondary students, university students, teachers and professionals) perceptions of language variation, English language teaching (ELT) and language use in their everyday communication via a large-scale questionnaire survey (N = 1893). Based on principal components analysis of the questionnaire…

Empirical Distributions of F ST from Large-Scale Human Polymorphism Data

PubMed Central

Elhaik, Eran

2012-01-01

Studies of the apportionment of human genetic variation have long established that most human variation is within population groups and that the additional variation between population groups is small but greatest when comparing different continental populations. These studies often used Wright’s F ST that apportions the standardized variance in allele frequencies within and between population groups. Because local adaptations increase population differentiation, high-F ST may be found at closely linked loci under selection and used to identify genes undergoing directional or heterotic selection. We re-examined these processes using HapMap data. We analyzed 3 million SNPs on 602 samples from eight worldwide populations and a consensus subset of 1 million SNPs found in all populations. We identified four major features of the data: First, a hierarchically F ST analysis showed that only a paucity (12%) of the total genetic variation is distributed between continental populations and even a lesser genetic variation (1%) is found between intra-continental populations. Second, the global F ST distribution closely follows an exponential distribution. Third, although the overall F ST distribution is similarly shaped (inverse J), F ST distributions varies markedly by allele frequency when divided into non-overlapping groups by allele frequency range. Because the mean allele frequency is a crude indicator of allele age, these distributions mark the time-dependent change in genetic differentiation. Finally, the change in mean-F ST of these groups is linear in allele frequency. These results suggest that investigating the extremes of the F ST distribution for each allele frequency group is more efficient for detecting selection. Consequently, we demonstrate that such extreme SNPs are more clustered along the chromosomes than expected from linkage disequilibrium for each allele frequency group. These genomic regions are therefore likely candidates for natural selection. PMID:23185452

Empirical distributions of F(ST) from large-scale human polymorphism data.

PubMed

Elhaik, Eran

2012-01-01

Studies of the apportionment of human genetic variation have long established that most human variation is within population groups and that the additional variation between population groups is small but greatest when comparing different continental populations. These studies often used Wright's F(ST) that apportions the standardized variance in allele frequencies within and between population groups. Because local adaptations increase population differentiation, high-F(ST) may be found at closely linked loci under selection and used to identify genes undergoing directional or heterotic selection. We re-examined these processes using HapMap data. We analyzed 3 million SNPs on 602 samples from eight worldwide populations and a consensus subset of 1 million SNPs found in all populations. We identified four major features of the data: First, a hierarchically F(ST) analysis showed that only a paucity (12%) of the total genetic variation is distributed between continental populations and even a lesser genetic variation (1%) is found between intra-continental populations. Second, the global F(ST) distribution closely follows an exponential distribution. Third, although the overall F(ST) distribution is similarly shaped (inverse J), F(ST) distributions varies markedly by allele frequency when divided into non-overlapping groups by allele frequency range. Because the mean allele frequency is a crude indicator of allele age, these distributions mark the time-dependent change in genetic differentiation. Finally, the change in mean-F(ST) of these groups is linear in allele frequency. These results suggest that investigating the extremes of the F(ST) distribution for each allele frequency group is more efficient for detecting selection. Consequently, we demonstrate that such extreme SNPs are more clustered along the chromosomes than expected from linkage disequilibrium for each allele frequency group. These genomic regions are therefore likely candidates for natural selection.

Genetic variation in laboratory and field populations of the vector of bluetongue virus, Culicoides variipennis (Diptera: Ceratopogonidae).

PubMed

Tabachnick, W J

1990-01-01

Laboratory colonies and several natural populations of the biting midge Culicoides variipennis (Coquillett) were analyzed for genetic variation at 21 electrophoretic loci. The laboratory colonies maintained high levels of genetic variation measured by average expected heterozygosities (He = 0.142 +/- 0.008), although levels were lower than those observed in field collections (He = 0.198 +/- 0.009). A field population from Colorado, analyzed five times over a 1-yr period, showed a consistent trend in the change in gene frequencies at two loci. Genetic comparisons between natural populations were consistent with the existence of two subspecies. C. variipennis variipennis and C. variipennis sonorensis Wirth & Jones.

The Evolution of Human Genetic and Phenotypic Variation in Africa

PubMed Central

Campbell, Michael C.

2010-01-01

Africa is the birthplace of modern humans, and is the source of the geographic expansion of ancestral populations into other regions of the world. Indigenous Africans are characterized by high levels of genetic diversity within and between populations. The pattern of genetic variation in these populations has been shaped by demographic events occurring over the last 200,000 years. The dramatic variation in climate, diet, and exposure to infectious disease across the continent has also resulted in novel genetic and phenotypic adaptations in extant Africans. This review summarizes some recent advances in our understanding of the demographic history and selective pressures that have influenced levels and patterns of diversity in African populations. PMID:20178763

An Investigation of the Relationship between Health Literacy and Social Communication Skills in Older Adults

ERIC Educational Resources Information Center

Hester, Eva Jackson

2009-01-01

The purpose of this study was to examine connections between health literacy and social communication skills in older adults, a population that experiences chronic health conditions but is reported to have low health literacy and declines in communication skills. Sixty-three older adults were administered the "Social Communication"…

Characterizing Communicative Development in Children Referred for Autism Spectrum Disorders Using the MacArthur-Bates Communicative Development Inventory (CDI)

ERIC Educational Resources Information Center

Luyster, Rhiannon; Lopez, Kristina; Lord, Catherine

2007-01-01

Characterizing early communicative development in children with Autism Spectrum Disorders (ASD) is valuable for understanding profiles of ability in this population. The current investigation was modeled on Charman, Drew, Baird & Baird (2003b). Analyses explored parent report of early vocabulary, non-verbal communication, functional object use and…

A framework for estimating the determinants of spatial and temporal variation in vital rates and inferring the occurrence of unobserved extreme events

PubMed Central

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

A framework for estimating the determinants of spatial and temporal variation in vital rates and inferring the occurrence of unobserved extreme events.

PubMed

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.

Learning Intercultural Communication Skills with Virtual Humans: Feedback and Fidelity

ERIC Educational Resources Information Center

Lane, H. Chad; Hays, Matthew Jensen; Core, Mark G.; Auerbach, Daniel

2013-01-01

In the context of practicing intercultural communication skills, we investigated the role of fidelity in a game-based, virtual learning environment as well as the role of feedback delivered by an intelligent tutoring system. In 2 experiments, we compared variations on the game interface, use of the tutoring system, and the form of the feedback.…

Social Networking and Pedagogical Variations: An Integrated Approach for Effective Interpersonal and Group Communications Skills Development

ERIC Educational Resources Information Center

Okoro, Ephraim

2012-01-01

Electronic communication and social networking are effective and useful tools in the process of teaching and learning and have increasingly improved the quality of students' learning outcomes in higher education in recent years. The system encourages and supports students' active engagement, collaboration, and participation in class activities and…

Mitochondrial DNA variation in natural populations of endangered Indian feather-back fish, Chitala chitala.

PubMed

Mandal, Anup; Mohindra, Vindhya; Singh, Rajeev Kumar; Punia, Peyush; Singh, Ajay Kumar; Lal, Kuldeep Kumar

2012-02-01

Genetic variation at mitochondrial cytochrome b (cyt b) and D-loop region reveals the evidence of population sub-structuring in Indian populations of highly endangered primitive feather-back fish Chitala chitala. Samples collected through commercial catches from eight riverine populations from different geographical locations of India were analyzed for cyt b region (307 bp) and D-loop region (636-716 bp). The sequences of the both the mitochondrial regions revealed high haplotype diversity and low nucleotide diversity. The patterns of genetic diversity, haplotypes networks clearly indicated two distinct mitochondrial lineages and mismatch distribution strongly suggest a historical influence on the genetic structure of C. chitala populations. The baseline information on genetic variation and the evidence of population sub-structuring generated from this study would be useful for planning effective strategies for conservation and rehabilitation of this highly endangered species.

Trophic status drives interannual variability in nesting numbers of marine turtles.

PubMed

Broderick, A C; Godley, B J; Hays, G C

2001-07-22

Large annual fluctuations are seen in breeding numbers in many populations of non-annual breeders. We examined the interannual variation in nesting numbers of populations of green (Chelonia mydas) (n = 16 populations), loggerhead (Caretta caretta) (n = 10 populations), leatherback (Dermochelys coriacea) (n = 9 populations) and hawksbill turtles (Eretmochelys imbricata) (n = 10 populations). Interannual variation was greatest in the green turtle. When comparing green and loggerhead turtles nesting in Cyprus we found that green turtles were more likely to change the interval between laying seasons and showed greater variation in the number of clutches laid in a season. We suggest that these differences are driven by the varying trophic statuses of the different species. Green turtles are herbivorous, feeding on sea grasses and macro-algae, and this primary production will be more tightly coupled with prevailing environmental conditions than the carnivorous diet of the loggerhead turtle.

Pharmacogenomic Research in South Africa: Lessons Learned and Future Opportunities in the Rainbow Nation.

PubMed

Warnich, Louise; Drögemöller, Britt I; Pepper, Michael S; Dandara, Collet; Wright, Galen E B

2011-09-01

South Africa, like many other developing countries, stands to benefit from novel diagnostics and drugs developed by pharmacogenomics guidance due to high prevalence of disease burden in the region. This includes both communicable (e.g., HIV/AIDS and tuberculosis) and non-communicable (e.g., diabetes and cardiovascular) diseases. For example, although only 0.7% of the world's population lives in South Africa, the country carries 17% of the global HIV/AIDS burden and 5% of the global tuberculosis burden. Nobel Peace Prize Laureate Archbishop Emeritus Desmond Tutu has coined the term Rainbow Nation, referring to a land of wealth in its many diverse peoples and cultures. It is now timely and necessary to reflect on how best to approach new genomics biotechnologies in a manner that carefully considers the public health needs and extant disease burden in the region. The aim of this paper is to document and review the advances in pharmacogenomics in South Africa and importantly, to evaluate the direction that future research should take. Previous research has shown that the populations in South Africa exhibit unique allele frequencies and novel genetic variation in pharmacogenetically relevant genes, often differing from other African and global populations. The high level of genetic diversity, low linkage disequilibrium and the presence of rare variants in these populations question the feasibility of the use of current commercially available genotyping platforms, and may partially account for genotype-phenotype discordance observed in past studies. However, the employment of high throughput technologies for genomic research, within the context of large clinical trials, combined with interdisciplinary studies and appropriate regulatory guidelines, should aid in acceleration of pharmacogenomic discoveries in high priority therapeutic areas in South Africa. Finally, we suggest that projects such as the H3Africa Initiative, the SAHGP and PGENI should play an integral role in the coordination of genomic research in South Africa, but also other African countries, by providing infrastructure and capital to local researchers, as well as providing aid in addressing the computational and statistical bottlenecks encountered at present.

Pharmacogenomic Research in South Africa: Lessons Learned and Future Opportunities in the Rainbow Nation

PubMed Central

Warnich, Louise; Drögemöller, Britt I; Pepper, Michael S; Dandara, Collet; Wright, Galen E.B

2011-01-01

South Africa, like many other developing countries, stands to benefit from novel diagnostics and drugs developed by pharmacogenomics guidance due to high prevalence of disease burden in the region. This includes both communicable (e.g., HIV/AIDS and tuberculosis) and non-communicable (e.g., diabetes and cardiovascular) diseases. For example, although only 0.7% of the world’s population lives in South Africa, the country carries 17% of the global HIV/AIDS burden and 5% of the global tuberculosis burden. Nobel Peace Prize Laureate Archbishop Emeritus Desmond Tutu has coined the term Rainbow Nation, referring to a land of wealth in its many diverse peoples and cultures. It is now timely and necessary to reflect on how best to approach new genomics biotechnologies in a manner that carefully considers the public health needs and extant disease burden in the region. The aim of this paper is to document and review the advances in pharmacogenomics in South Africa and importantly, to evaluate the direction that future research should take. Previous research has shown that the populations in South Africa exhibit unique allele frequencies and novel genetic variation in pharmacogenetically relevant genes, often differing from other African and global populations. The high level of genetic diversity, low linkage disequilibrium and the presence of rare variants in these populations question the feasibility of the use of current commercially available genotyping platforms, and may partially account for genotype-phenotype discordance observed in past studies. However, the employment of high throughput technologies for genomic research, within the context of large clinical trials, combined with interdisciplinary studies and appropriate regulatory guidelines, should aid in acceleration of pharmacogenomic discoveries in high priority therapeutic areas in South Africa. Finally, we suggest that projects such as the H3Africa Initiative, the SAHGP and PGENI should play an integral role in the coordination of genomic research in South Africa, but also other African countries, by providing infrastructure and capital to local researchers, as well as providing aid in addressing the computational and statistical bottlenecks encountered at present. PMID:22563365

Genetic variation for pseudo-self-compatibility in self-incompatible populations of Leavenworthia alabamica (Brassicaceae).

PubMed

Baldwin, Sarah J; Schoen, Daniel J

2017-01-01

Self-incompatibility (SI) promotes outcrossing, but transitions to self-compatibility (SC) are frequent. Population genetic theory describing the breakdown of SI to SC suggests that, under most conditions, populations should be composed of either SI or SC individuals. Under a narrow range of conditions, theory suggests that SI may persist alongside reduced expression of SI (pseudo-SI, PSI) in mixed-mating populations. We studied genetic variation for PSI segregating in four SI populations of Leavenworthia alabamica by measurement of the heritability of pollen tube number after self-pollination. We tested for the role of the S-locus in this variation by sequencing seven S-alleles from plants with high pseudo-SC (PSC) and testing for the co-segregation of these alleles with PSC. We found a continuous distribution of PSC in all populations and 90% of plants exhibited PSC. The heritability ranged from 0.39 to 0.57. All seven S-alleles from plants with high PSC exhibited trans-specific polymorphism, and no stop codons were observed within the c. 600-bp region sequenced. One of these S-alleles was directly associated with the inheritance of PSC. We conclude that heritable variation in PSC is largely a result of genetic variation in the signaling cascade downstream of the S-locus reaction, together with the presence of one leaky S-allele. © 2016 The Authors. New Phytologist © 2016 New Phytologist Trust.

Postpollination discrimination between self and outcross pollen covaries with the mating system of a self-compatible flowering plant.

PubMed

Cruzan, Mitchell B; Barrett, Spencer C H

2016-03-01

Variation in the mating system of hermaphroditic plant populations is determined by interactions between genetic and environmental factors operating via both pre- and postmating processes. Models predicting the maintenance of intermediate outcrossing rates in animal-pollinated plants often assume that the mating system is primarily controlled by floral morphology and pollinator availability, but rarely has the influence of postpollination processes on variation in outcrossing been examined. We investigated the influence of stylar discrimination between illegitimate and legitimate pollen-tube growth and the pollen-load capacity of stigmas on mating-system variation in the annual, tristylous species Eichhornia paniculata using controlled crosses and genetic markers. This species exhibits an exceptionally broad range of outcrossing rates in natural populations. There was significant variation among populations in the pollen-load capacity of stigmas and the ability of styles to discriminate between illegitimate vs. legitimate pollen. There was strong correspondence between stylar-discrimination ability and variation in outcrossing rate among populations and style morphs. The combination of stigmatic pollen-load capacity and stylar discrimination explained more than 80% of the variation in outcrossing rates among populations. The finding that stigmatic pollen-load capacity and stylar-discrimination ability contributed significantly to explaining the wide range of outcrossing rates in E. paniculata suggests that postpollination mechanisms play an important role in governing mating patterns in this species. The difference in levels of stylar discrimination between outcrossing and selfing populations may reflect a trade-off between selection for increased outcrossing and greater reproductive assurance. © 2016 Botanical Society of America.

Genetic diversity and differentiation in a wide ranging anadromous fish, American shad (Alosa sapidissima), is correlated with latitude.

PubMed

Hasselman, Daniel J; Ricard, Daniel; Bentzen, Paul

2013-03-01

Studies that span entire species ranges can provide insight into the relative roles of historical contingency and contemporary factors that influence population structure and can reveal patterns of genetic variation that might otherwise go undetected. American shad is a wide ranging anadromous clupeid fish that exhibits variation in demographic histories and reproductive strategies (both semelparity and iteroparity) and provides a unique perspective on the evolutionary processes that govern the genetic architecture of anadromous fishes. Using 13 microsatellite loci, we examined the magnitude and spatial distribution of genetic variation among 33 populations across the species' range to (i) determine whether signals of historical demography persist among contemporary populations and (ii) assess the effect of different reproductive strategies on population structure. Patterns of genetic diversity and differentiation among populations varied widely and reflect the differential influences of historical demography, microevolutionary processes and anthropogenic factors across the species' range. Sequential reductions of diversity with latitude among formerly glaciated rivers are consistent with stepwise postglacial colonization and successive population founder events. Weak differentiation among U.S. iteroparous populations may be a consequence of human-mediated gene flow, while weak differentiation among semelparous populations probably reflects natural gene flow. Evidence for an effect of reproductive strategy on population structure suggests an important role for environmental variation and suggests that the factors that are responsible for shaping American shad life history patterns may also influence population genetic structure. © 2013 Blackwell Publishing Ltd.

Whole genome sequencing of Turkish genomes reveals functional private alleles and impact of genetic interactions with Europe, Asia and Africa.

PubMed

Alkan, Can; Kavak, Pinar; Somel, Mehmet; Gokcumen, Omer; Ugurlu, Serkan; Saygi, Ceren; Dal, Elif; Bugra, Kuyas; Güngör, Tunga; Sahinalp, S Cenk; Özören, Nesrin; Bekpen, Cemalettin

2014-11-07

Turkey is a crossroads of major population movements throughout history and has been a hotspot of cultural interactions. Several studies have investigated the complex population history of Turkey through a limited set of genetic markers. However, to date, there have been no studies to assess the genetic variation at the whole genome level using whole genome sequencing. Here, we present whole genome sequences of 16 Turkish individuals resequenced at high coverage (32×-48×). We show that the genetic variation of the contemporary Turkish population clusters with South European populations, as expected, but also shows signatures of relatively recent contribution from ancestral East Asian populations. In addition, we document a significant enrichment of non-synonymous private alleles, consistent with recent observations in European populations. A number of variants associated with skin color and total cholesterol levels show frequency differentiation between the Turkish populations and European populations. Furthermore, we have analyzed the 17q21.31 inversion polymorphism region (MAPT locus) and found increased allele frequency of 31.25% for H1/H2 inversion polymorphism when compared to European populations that show about 25% of allele frequency. This study provides the first map of common genetic variation from 16 western Asian individuals and thus helps fill an important geographical gap in analyzing natural human variation and human migration. Our data will help develop population-specific experimental designs for studies investigating disease associations and demographic history in Turkey.

Estimation and Partitioning of Heritability in Human Populations using Whole Genome Analysis Methods

PubMed Central

Vinkhuyzen, Anna AE; Wray, Naomi R; Yang, Jian; Goddard, Michael E; Visscher, Peter M

2014-01-01

Understanding genetic variation of complex traits in human populations has moved from the quantification of the resemblance between close relatives to the dissection of genetic variation into the contributions of individual genomic loci. But major questions remain unanswered: how much phenotypic variation is genetic, how much of the genetic variation is additive and what is the joint distribution of effect size and allele frequency at causal variants? We review and compare three whole-genome analysis methods that use mixed linear models (MLM) to estimate genetic variation, using the relationship between close or distant relatives based on pedigree or SNPs. We discuss theory, estimation procedures, bias and precision of each method and review recent advances in the dissection of additive genetic variation of complex traits in human populations that are based upon the application of MLM. Using genome wide data, SNPs account for far more of the genetic variation than the highly significant SNPs associated with a trait, but they do not account for all of the genetic variance estimated by pedigree based methods. We explain possible reasons for this ‘missing’ heritability. PMID:23988118

Flower-level developmental plasticity to nutrient availability in Datura stramonium: implications for the mating system.

PubMed

Camargo, Iván Darío; Nattero, Julieta; Careaga, Sonia A; Núñez-Farfán, Juan

2017-10-17

Studies of phenotypic plasticity in plants have mainly focused on (1) the effect of environmental variation on whole-plant traits related to the number of modules rather than on (2) the phenotypic consequences of environmental variation in traits of individual modules. Since environmental and developmental factors can produce changes in traits related to the mating system, this study used the second approach to investigate whether within-individual variation in herkogamy-related traits is affected by the environment during plant development in two populations of Datura stramonium , an annual herb with a hypothesized persistent mixed mating system, and to determine which morphological traits may promote self-fertilization. Full-sib families of two Mexican populations of D. stramonium , with contrasting ecological histories, were grown under low, mid and high nutrient availability to investigate the effects of genetic, environmental and within-plant flower position on flower size, corolla, stamen and pistil lengths, and herkogamy. Populations showed differences in familial variation, plasticity and familial differences in plasticity in most floral traits analysed. In one population (Ticumán), the effect of flower position on trait variation varied among families, whereas in the other (Pedregal) the effect of flower position interacted with the nutrient environment. Flower size varied with the position of flowers, but in the opposite direction between populations in low nutrients; a systematic within-plant trend of reduction in flower size, pistil length and herkogamy with flower position increased the probability of self-fertilization in the Pedregal population. Besides genetic variation in floral traits between and within populations, environmental variation affects phenotypic floral trait values at the whole-plant level, as well as among flower positions. The interaction between flower position and nutrient environment can affect the plant's mating system, and this differs between populations. Thus, reductions in herkogamy with flower positions may be expected in environments with either low pollinator abundance or low nutrients. © The Author 2017. Published by Oxford University Press on behalf of the Annals of Botany Company. All rights reserved. For Permissions, please email: journals.permissions@oup.com

The genealogy and genetic viability of reintroduced Yellowstone grey wolves.

PubMed

Vonholdt, Bridgett M; Stahler, Daniel R; Smith, Douglas W; Earl, Dent A; Pollinger, John P; Wayne, Robert K

2008-01-01

The recovery of the grey wolf in Yellowstone National Park is an outstanding example of a successful reintroduction. A general question concerning reintroduction is the degree to which genetic variation has been preserved and the specific behavioural mechanisms that enhance the preservation of genetic diversity and reduce inbreeding. We have analysed 200 Yellowstone wolves, including all 31 founders, for variation in 26 microsatellite loci over the 10-year reintroduction period (1995-2004). The population maintained high levels of variation (1995 H(0) = 0.69; 2004 H(0) = 0.73) with low levels of inbreeding (1995 F(IS) = -0.063; 2004 F(IS) = -0.051) and throughout, the population expanded rapidly (N(1995) = 21; N(2004) = 169). Pedigree-based effective population size ratios did not vary appreciably over the duration of population expansion (1995 N(e)/N(g) = 0.29; 2000 N(e)/N(g) = 0.26; 2004 N(e)/N(g) = 0.33). We estimated kinship and found only two of 30 natural breeding pairs showed evidence of being related (average r = -0.026, SE = 0.03). We reconstructed the genealogy of 200 wolves based on genetic and field data and discovered that they avoid inbreeding through a wide variety of behavioural mechanisms including absolute avoidance of breeding with related pack members, male-biased dispersal to packs where they breed with nonrelatives, and female-biased subordinate breeding. We documented a greater diversity of such population assembly patterns in Yellowstone than previously observed in any other natural wolf population. Inbreeding avoidance is nearly absolute despite the high probability of within-pack inbreeding opportunities and extensive interpack kinship ties between adjacent packs. Simulations showed that the Yellowstone population has levels of genetic variation similar to that of a population managed for high variation and low inbreeding, and greater than that expected for random breeding within packs or across the entire breeding pool. Although short-term losses in variation seem minimal, future projections of the population at carrying capacity suggest significant inbreeding depression will occur without connectivity and migratory exchange with other populations.

Intrapopulation variation in stature and body proportions: social status and sex differences in an Italian medieval population (Trino Vercellese, VC).

PubMed

Vercellotti, Giuseppe; Stout, Sam D; Boano, Rosa; Sciulli, Paul W

2011-06-01

The phenotypic expression of adult body size and shape results from synergistic interactions between hereditary factors and environmental conditions experienced during growth. Variation in body size and shape occurs even in genetically relatively homogeneous groups, due to different occurrence, duration, and timing of growth insults. Understanding the causes and patterns of intrapopulation variation can foster meaningful information on early life conditions in living and past populations. This study assesses the pattern of biological variation in body size and shape attributable to sex and social status in a medieval Italian population. The sample includes 52 (20 female, 32 male) adult individuals from the medieval population of Trino Vercellese, Italy. Differences in element size and overall body size (skeletal height and body mass) were assessed through Monte Carlo methods, while univariate non-parametric tests and Principal Component Analysis (PCA) were employed to examine segmental and overall body proportions. Discriminant Analysis was employed to determine the predictive value of individual skeletal elements for social status in the population. Our results highlight a distinct pattern in body size and shape variation in relation to status and sex. Male subsamples exhibit significant postcranial variation in body size, while female subsamples express smaller, nonsignificant differences. The analysis of segmental proportions highlighted differences in trunk/lower limb proportions between different status samples, and PCA indicated that in terms of purely morphological variation high status males were distinct from all other groups. The pattern observed likely resulted from a combination of biological factors and cultural practices. Copyright © 2011 Wiley-Liss, Inc.

Genetic variation in bacterial kidney disease (BKD) susceptibility in Lake Michigan Chinook Salmon and its progenitor population from the Puget Sound.

PubMed

Purcell, Maureen K; Hard, Jeffrey J; Neely, Kathleen G; Park, Linda K; Winton, James R; Elliott, Diane G

2014-03-01

Mass mortality events in wild fish due to infectious diseases are troubling, especially given the potential for long-term, population-level consequences. Evolutionary theory predicts that populations with sufficient genetic variation will adapt in response to pathogen pressure. Chinook Salmon Oncorhynchus tshawytscha were introduced into Lake Michigan in the late 1960s from a Washington State hatchery population. In the late 1980s, collapse of the forage base and nutritional stress in Lake Michigan were thought to contribute to die-offs of Chinook Salmon due to bacterial kidney disease (BKD). Previously, we demonstrated that Lake Michigan Chinook Salmon from a Wisconsin hatchery have greater survival following BKD challenge relative to their progenitor population. Here, we evaluated whether the phenotypic divergence of these populations in BKD susceptibility was due to selection rather than genetic drift. Comparison of the overall magnitude of quantitative trait to neutral marker divergence between the populations suggested selection had occurred but a direct test of quantitative trait divergence was not significant, preventing the rejection of the null hypothesis of differentiation through genetic drift. Estimates of phenotypic variation (VP ), additive genetic variation (VA ) and narrow-sense heritability (h (2)) were consistently higher in the Wisconsin relative to the Washington population. If selection had acted on the Wisconsin population there was no evidence of a concomitant loss of genetic variation in BKD susceptibility. The Renibacterium salmoninarum exposures were conducted at both 14°C and 9°C; the warmer temperature accelerated time to death in both populations and there was no evidence of phenotypic plasticity or a genotype-by-environment (G × E) interaction. High h (2) estimates for BKD susceptibility in the Wisconsin population, combined with a lack of phenotypic plasticity, predicts that future adaptive gains in BKD resistance are still possible and that these adaptive gains would be stable under the temperature range evaluated here.

Genetic variation in bacterial kidney disease (BKD) susceptibility in Lake Michigan Chinook Salmon and its progenitor population from the Puget Sound

USGS Publications Warehouse

Purcell, Maureen K.; Hard, Jeffrey J.; Neely, Kathleen G.; Park, Linda K.; Winton, James R.; Elliott, Diane G.

2014-01-01

Mass mortality events in wild fish due to infectious diseases are troubling, especially given the potential for long-term, population-level consequences. Evolutionary theory predicts that populations with sufficient genetic variation will adapt in response to pathogen pressure. Chinook Salmon Oncorhynchus tshawytscha were introduced into Lake Michigan in the late 1960s from a Washington State hatchery population. In the late 1980s, collapse of the forage base and nutritional stress in Lake Michigan were thought to contribute to die-offs of Chinook Salmon due to bacterial kidney disease (BKD). Previously, we demonstrated that Lake Michigan Chinook Salmon from a Wisconsin hatchery have greater survival following BKD challenge relative to their progenitor population. Here, we evaluated whether the phenotypic divergence of these populations in BKD susceptibility was due to selection rather than genetic drift. Comparison of the overall magnitude of quantitative trait to neutral marker divergence between the populations suggested selection had occurred but a direct test of quantitative trait divergence was not significant, preventing the rejection of the null hypothesis of differentiation through genetic drift. Estimates of phenotypic variation (VP), additive genetic variation (VA) and narrow-sense heritability (h2) were consistently higher in the Wisconsin relative to the Washington population. If selection had acted on the Wisconsin population there was no evidence of a concomitant loss of genetic variation in BKD susceptibility. The Renibacterium salmoninarum exposures were conducted at both 14°C and 9°C; the warmer temperature accelerated time to death in both populations and there was no evidence of phenotypic plasticity or a genotype-by-environment (G × E) interaction. High h2 estimates for BKD susceptibility in the Wisconsin population, combined with a lack of phenotypic plasticity, predicts that future adaptive gains in BKD resistance are still possible and that these adaptive gains would be stable under the temperature range evaluated here.

Patterns of genetic differentiation at MHC class I genes and microsatellites identify conservation units in the giant panda.

PubMed

Zhu, Ying; Wan, Qiu-Hong; Yu, Bin; Ge, Yun-Fa; Fang, Sheng-Guo

2013-10-22

Evaluating patterns of genetic variation is important to identify conservation units (i.e., evolutionarily significant units [ESUs], management units [MUs], and adaptive units [AUs]) in endangered species. While neutral markers could be used to infer population history, their application in the estimation of adaptive variation is limited. The capacity to adapt to various environments is vital for the long-term survival of endangered species. Hence, analysis of adaptive loci, such as the major histocompatibility complex (MHC) genes, is critical for conservation genetics studies. Here, we investigated 4 classical MHC class I genes (Aime-C, Aime-F, Aime-I, and Aime-L) and 8 microsatellites to infer patterns of genetic variation in the giant panda (Ailuropoda melanoleuca) and to further define conservation units. Overall, we identified 24 haplotypes (9 for Aime-C, 1 for Aime-F, 7 for Aime-I, and 7 for Aime-L) from 218 individuals obtained from 6 populations of giant panda. We found that the Xiaoxiangling population had the highest genetic variation at microsatellites among the 6 giant panda populations and higher genetic variation at Aime-MHC class I genes than other larger populations (Qinling, Qionglai, and Minshan populations). Differentiation index (FST)-based phylogenetic and Bayesian clustering analyses for Aime-MHC-I and microsatellite loci both supported that most populations were highly differentiated. The Qinling population was the most genetically differentiated. The giant panda showed a relatively higher level of genetic diversity at MHC class I genes compared with endangered felids. Using all of the loci, we found that the 6 giant panda populations fell into 2 ESUs: Qinling and non-Qinling populations. We defined 3 MUs based on microsatellites: Qinling, Minshan-Qionglai, and Daxiangling-Xiaoxiangling-Liangshan. We also recommended 3 possible AUs based on MHC loci: Qinling, Minshan-Qionglai, and Daxiangling-Xiaoxiangling-Liangshan. Furthermore, we recommend that a captive breeding program be considered for the Qinling panda population.

The Roles of Standing Genetic Variation and Evolutionary History in Determining the Evolvability of Anti-Predator Strategies

PubMed Central

Dworkin, Ian; Wagner, Aaron P.

2014-01-01

Standing genetic variation and the historical environment in which that variation arises (evolutionary history) are both potentially significant determinants of a population's capacity for evolutionary response to a changing environment. Using the open-ended digital evolution software Avida, we evaluated the relative importance of these two factors in influencing evolutionary trajectories in the face of sudden environmental change. We examined how historical exposure to predation pressures, different levels of genetic variation, and combinations of the two, affected the evolvability of anti-predator strategies and competitive abilities in the presence or absence of threats from new, invasive predator populations. We show that while standing genetic variation plays some role in determining evolutionary responses, evolutionary history has the greater influence on a population's capacity to evolve anti-predator traits, i.e. traits effective against novel predators. This adaptability likely reflects the relative ease of repurposing existing, relevant genes and traits, and the broader potential value of the generation and maintenance of adaptively flexible traits in evolving populations. PMID:24955847

Sex ratio variation shapes the ecological effects of a globally introduced freshwater fish

PubMed Central

Fryxell, David C.; Arnett, Heather A.; Apgar, Travis M.; Kinnison, Michael T.; Palkovacs, Eric P.

2015-01-01

Sex ratio and sexual dimorphism have long been of interest in population and evolutionary ecology, but consequences for communities and ecosystems remain untested. Sex ratio could influence ecological conditions whenever sexual dimorphism is associated with ecological dimorphism in species with strong ecological interactions. We tested for ecological implications of sex ratio variation in the sexually dimorphic western mosquitofish, Gambusia affinis. This species causes strong pelagic trophic cascades and exhibits substantial variation in adult sex ratios. We found that female-biased populations induced stronger pelagic trophic cascades compared with male-biased populations, causing larger changes to key community and ecosystem responses, including zooplankton abundance, phytoplankton abundance, productivity, pH and temperature. The magnitude of such effects indicates that sex ratio is important for mediating the ecological role of mosquitofish. Because both sex ratio variation and sexual dimorphism are common features of natural populations, our findings should encourage broader consideration of the ecological significance of sex ratio variation in nature, including the relative contributions of various sexually dimorphic traits to these effects. PMID:26490793

Analysis of the “naming game” with learning errors in communications

NASA Astrophysics Data System (ADS)

Lou, Yang; Chen, Guanrong

2015-07-01

Naming game simulates the process of naming an objective by a population of agents organized in a certain communication network. By pair-wise iterative interactions, the population reaches consensus asymptotically. We study naming game with communication errors during pair-wise conversations, with error rates in a uniform probability distribution. First, a model of naming game with learning errors in communications (NGLE) is proposed. Then, a strategy for agents to prevent learning errors is suggested. To that end, three typical topologies of communication networks, namely random-graph, small-world and scale-free networks, are employed to investigate the effects of various learning errors. Simulation results on these models show that 1) learning errors slightly affect the convergence speed but distinctively increase the requirement for memory of each agent during lexicon propagation; 2) the maximum number of different words held by the population increases linearly as the error rate increases; 3) without applying any strategy to eliminate learning errors, there is a threshold of the learning errors which impairs the convergence. The new findings may help to better understand the role of learning errors in naming game as well as in human language development from a network science perspective.

Analysis of the "naming game" with learning errors in communications.

PubMed

Lou, Yang; Chen, Guanrong

2015-07-16

Naming game simulates the process of naming an objective by a population of agents organized in a certain communication network. By pair-wise iterative interactions, the population reaches consensus asymptotically. We study naming game with communication errors during pair-wise conversations, with error rates in a uniform probability distribution. First, a model of naming game with learning errors in communications (NGLE) is proposed. Then, a strategy for agents to prevent learning errors is suggested. To that end, three typical topologies of communication networks, namely random-graph, small-world and scale-free networks, are employed to investigate the effects of various learning errors. Simulation results on these models show that 1) learning errors slightly affect the convergence speed but distinctively increase the requirement for memory of each agent during lexicon propagation; 2) the maximum number of different words held by the population increases linearly as the error rate increases; 3) without applying any strategy to eliminate learning errors, there is a threshold of the learning errors which impairs the convergence. The new findings may help to better understand the role of learning errors in naming game as well as in human language development from a network science perspective.

Life history variation among geographically close populations of the toad-headed lizard (Phrynocephalus przewalskii): Exploring environmental and physiological associations

NASA Astrophysics Data System (ADS)

Zeng, Zhi-Gao; Zhao, Jia-Ming; Sun, Bao-Jun

2013-08-01

Geographic variation in life history traits has been extensively studied along latitudinal and altitudinal clines, but life history variation among geographically close populations has received much less attention. We collected gravid female toad-headed lizards (Phrynocephalus przewalskii) and environmental data from three localities (Alxa Zuoqi, Alxa Youqi, and Shandan) across the Gobi desert in China, to examine among-population differences in reproductive strategies. The precipitation was significantly lower in Alxa Youqi than Alxa Zouqi and Shandan. Food availability was highest in Shandan, lowest in Alxa Zuoqi, with Alxa Youqi in between. Females from Shandan population were larger and produced more and larger eggs than their counterparts from the other two populations. Incubation period also differed among the populations, with the lowest incubation period in Alxa Youqi population, and the longest incubation period in Alxa Zuoqi population. Our data on the physiological mechanisms of incubation period indicated that the shortened incubation period in Alxa Youqi population was due to advanced embryogenesis completed prior to oviposition rather than higher embryonic heart rates during incubation. Therefore, our data support the hypothesis that geographically close populations can show different reproductive strategies if environmental factors vary among these populations.

Phenotypic expression of partial AZFc deletions is independent of the variations in DAZL and BOULE in a Han population.

PubMed

Chen, Pu; Ma, Mingyi; Li, Lei; Zhang, Sizhong; Su, Dan; Ma, Yongxin; Liu, Yunqiang; Tao, Dachang; Lin, Li; Yang, Yuan

2010-01-01

DAZ on the Y chromosome and 2 autosomal ancestral genes DAZL and BOULE are suggested to represent functional conservation in spermatogenesis. The partial AZFc deletion, a common mutation of the Y chromosome, always involves 2 DAZ copies and represents a different spermatogenic phenotype in the populations studied. To investigate whether the variations in DAZL and BOULE influence partial AZFc deletion phenotype, the genotyping of 15 loci variations, including 4 known mutations and 11 single-nucleotide polymorphisms (SNPs), was carried out in 157 azoo-/oligzoospermic men and 57 normozoospermic men, both groups with partial AZFc deletions. The frequencies of the alleles, genotypes, and haplotypes of the variations were compared between the 2 groups. As a result, for 9 exonic variations in DAZL and BOULE, only T12A was observed in both groups with similar frequency, and I71V was identified in an azoospermic man with b2/b3 deletion, whereas the rest were absent in the population. The distribution of DAZL haplotypes from 4 variations, including T12A, and of BOULE haplotypes from 2 SNPs was similar between men with normozoospermia and spermatogenic failure. Our findings indicate that the contribution of DAZL and BOULE variations to spermatogenic impairment in men with the DAZ defect is greatly limited, suggesting that expression of spermatogenic phenotypes of partial AZFc deletions is independent of the variations in DAZL and BOULE in the Han population.

Evaluating abundance and trends in a Hawaiian avian community using state-space analysis

USGS Publications Warehouse

Camp, Richard J.; Brinck, Kevin W.; Gorresen, P.M.; Paxton, Eben H.

2016-01-01

Estimating population abundances and patterns of change over time are important in both ecology and conservation. Trend assessment typically entails fitting a regression to a time series of abundances to estimate population trajectory. However, changes in abundance estimates from year-to-year across time are due to both true variation in population size (process variation) and variation due to imperfect sampling and model fit. State-space models are a relatively new method that can be used to partition the error components and quantify trends based only on process variation. We compare a state-space modelling approach with a more traditional linear regression approach to assess trends in uncorrected raw counts and detection-corrected abundance estimates of forest birds at Hakalau Forest National Wildlife Refuge, Hawai‘i. Most species demonstrated similar trends using either method. In general, evidence for trends using state-space models was less strong than for linear regression, as measured by estimates of precision. However, while the state-space models may sacrifice precision, the expectation is that these estimates provide a better representation of the real world biological processes of interest because they are partitioning process variation (environmental and demographic variation) and observation variation (sampling and model variation). The state-space approach also provides annual estimates of abundance which can be used by managers to set conservation strategies, and can be linked to factors that vary by year, such as climate, to better understand processes that drive population trends.

Communicating effectively with vulnerable populations during water contamination events.

PubMed

Nsiah-Kumi, Phyllis A

2008-01-01

Water contamination events are a public health concern worldwide with significant potential to impact the global community. When communicating with the public during these crisis situations, it is vital to consider the multiple audiences who receive the messages. Before developing or delivering messages to a particular community, it is essential to be familiar with the community's characteristics, needs, concerns, and who is considered credible to that community. Vulnerable populations are those with difficulties in comprehension or accessibility that may limit their full understanding of risks and may mitigate the effectiveness of public health strategies. Vulnerable populations include, but are not limited to, the urban/rural poor, those who are mentally ill, intellectually disabled, medically vulnerable, at the extremes of age (children and the elderly), racial/ethnic minorities, and those with low literacy or limited English proficiency.A water contamination event poses a unique opportunity to work with diverse populations to effectively convey important health messages. Each population needs to receive appropriate public health messages. Becoming familiar with vulnerable populations and their needs prior to a water contamination event will help in identifying barriers and developing and refining effective messages in such a crisis. In water contamination crises, our publics' health depends on effective, targeted crisis communication.

Can We Communicate with Other Generations?

ERIC Educational Resources Information Center

Mellert, Robert B.

Communicating with future generations is not merely a question of "how" to communicate, but also of "what." Our major moral responsibilities to future generations concern the size of future populations, conservation of nonrenewable resources, diversity of the gene pool, and quality of the environment. To determine our…

Seasonal variation in the free-running period in two Talitrus saltator populations from Italian beaches differing in morphodynamics and human disturbance

NASA Astrophysics Data System (ADS)

Nardi, M.; Morgan, E.; Scapini, F.

2003-10-01

The sandhopper Talitrus saltator Montagu (Amphipoda) is a widespread species adapted to different changing environmental conditions and which typically shows a clear circadian rhythm of locomotor activity. The populations from two beaches on the western Italian coast differing in coastline dynamics (eroded versus dynamically stable) and human disturbance (inside a natural park versus freely used and cleaned for leisure) were studied to highlight intrapopulation variation in the endogenous locomotor rhythm. The activity of adult sandhoppers was studied under constant laboratory conditions within individual recording chambers. Variation of the free-running period was analysed at individual level within each population. Greater variability was found than previously reported for the circadian rhythm period of T. saltator, and seasonal variation was shown for the first time. Differences in the level of variation were correlated with coastline dynamics.

Architecture and functional ecology of the human gastrocnemius muscle-tendon unit.

PubMed

Butler, Erin E; Dominy, Nathaniel J

2016-04-01

The gastrocnemius muscle-tendon unit (MTU) is central to human locomotion. Structural variation in the human gastrocnemius MTU is predicted to affect the efficiency of locomotion, a concept most often explored in the context of performance activities. For example, stiffness of the Achilles tendon varies among individuals with different histories of competitive running. Such a finding highlights the functional variation of individuals and raises the possibility of similar variation between populations, perhaps in response to specific ecological or environmental demands. Researchers often assume minimal variation in human populations, or that industrialized populations represent the human species as well as any other. Yet rainforest hunter-gatherers, which often express the human pygmy phenotype, contradict such assumptions. Indeed, the human pygmy phenotype is a potential model system for exploring the range of ecomorphological variation in the architecture of human hindlimb muscles, a concept we review here. © 2015 Anatomical Society.

Genetic diversity and population structure in contemporary house sparrow populations along an urbanization gradient

PubMed Central

Vangestel, C; Mergeay, J; Dawson, D A; Callens, T; Vandomme, V; Lens, L

2012-01-01

House sparrow (Passer domesticus) populations have suffered major declines in urban as well as rural areas, while remaining relatively stable in suburban ones. Yet, to date no exhaustive attempt has been made to examine how, and to what extent, spatial variation in population demography is reflected in genetic population structuring along contemporary urbanization gradients. Here we use putatively neutral microsatellite loci to study if and how genetic variation can be partitioned in a hierarchical way among different urbanization classes. Principal coordinate analyses did not support the hypothesis that urban/suburban and rural populations comprise two distinct genetic clusters. Comparison of FST values at different hierarchical scales revealed drift as an important force of population differentiation. Redundancy analyses revealed that genetic structure was strongly affected by both spatial variation and level of urbanization. The results shown here can be used as baseline information for future genetic monitoring programmes and provide additional insights into contemporary house sparrow dynamics along urbanization gradients. PMID:22588131

Genetic diversity and population structure in contemporary house sparrow populations along an urbanization gradient.

PubMed

Vangestel, C; Mergeay, J; Dawson, D A; Callens, T; Vandomme, V; Lens, L

2012-09-01

House sparrow (Passer domesticus) populations have suffered major declines in urban as well as rural areas, while remaining relatively stable in suburban ones. Yet, to date no exhaustive attempt has been made to examine how, and to what extent, spatial variation in population demography is reflected in genetic population structuring along contemporary urbanization gradients. Here we use putatively neutral microsatellite loci to study if and how genetic variation can be partitioned in a hierarchical way among different urbanization classes. Principal coordinate analyses did not support the hypothesis that urban/suburban and rural populations comprise two distinct genetic clusters. Comparison of FST values at different hierarchical scales revealed drift as an important force of population differentiation. Redundancy analyses revealed that genetic structure was strongly affected by both spatial variation and level of urbanization. The results shown here can be used as baseline information for future genetic monitoring programmes and provide additional insights into contemporary house sparrow dynamics along urbanization gradients.

Variation in Age and Size in Fennoscandian Three-Spined Sticklebacks (Gasterosteus aculeatus)

PubMed Central

DeFaveri, Jacquelin; Merilä, Juha

2013-01-01

Average age and maximum life span of breeding adult three-spined sticklebacks (Gasterosteus aculeatus) were determined in eight Fennoscandian localities with the aid of skeletochronology. The average age varied from 1.8 to 3.6 years, and maximum life span from three to six years depending on the locality. On average, fish from marine populations were significantly older than those from freshwater populations, but variation within habitat types was large. We also found significant differences in mean body size among different habitat types and populations, but only the population differences remained significant after accounting for variation due to age effects. These results show that generation length and longevity in three-spined sticklebacks can vary significantly from one locality to another, and that population differences in mean body size cannot be explained as a simple consequence of differences in population age structure. We also describe a nanistic population from northern Finland exhibiting long life span and small body size. PMID:24260496

Variation in age and size in Fennoscandian three-spined sticklebacks (Gasterosteus aculeatus).

PubMed

DeFaveri, Jacquelin; Merilä, Juha

2013-01-01

Average age and maximum life span of breeding adult three-spined sticklebacks (Gasterosteus aculeatus) were determined in eight Fennoscandian localities with the aid of skeletochronology. The average age varied from 1.8 to 3.6 years, and maximum life span from three to six years depending on the locality. On average, fish from marine populations were significantly older than those from freshwater populations, but variation within habitat types was large. We also found significant differences in mean body size among different habitat types and populations, but only the population differences remained significant after accounting for variation due to age effects. These results show that generation length and longevity in three-spined sticklebacks can vary significantly from one locality to another, and that population differences in mean body size cannot be explained as a simple consequence of differences in population age structure. We also describe a nanistic population from northern Finland exhibiting long life span and small body size.

Stakeholder opinion of functional communication activities following traumatic brain injury.

PubMed

Larkins, B M; Worrall, L E; Hickson, L M

2004-07-01

To establish a process whereby assessment of functional communication reflects the authentic communication of the target population. The major functional communication assessments available from the USA may not be as relevant to those who reside elsewhere, nor assessments developed primarily for persons who have had a stroke as relevant for traumatic brain injury rehabilitation. The investigation used the Nominal Group Technique to elicit free opinion and support individuals who have compromised communication ability. A survey mailed out sampled a larger number of stakeholders to test out differences among groups. Five stakeholder groups generated items and the survey determined relative 'importance'. The stakeholder groups in both studies comprised individuals with traumatic brain injury and their families, health professionals, third-party payers, employers, and Maori, the indigenous population of New Zealand. There was no statistically significant difference found between groups for 19 of the 31 items. Only half of the items explicitly appear on a well-known USA functional communication assessment. The present study has implications for whether functional communication assessments are valid across cultures and the type of impairment.

Ecological significance of microsatellite variation in western North American populations of Bromus tectorum

Treesearch

Alisa P. Ramakrishnan; Susan Meyer; Daniel J. Fairbanks; Craig E. Coleman

2006-01-01

Bromus tectorum (cheatgrass or downy brome) is an exotic annual weed that is abundant in western USA. We examined variation in six microsatellite loci for 17 populations representing a range of habitats in Utah, Idaho, Nevada and Colorado (USA) and then intensively sampled four representative populations, for a total sample size of approximately 1000 individuals. All...

Genetic conservation and management of the Californian endemic, Torrey Pine (Pinus torreyana Parry)

Treesearch

Jill A. Hamilton; Jessica W. Wright; F. Thomas Ledig

2017-01-01

Torrey pine (Pinus torreyana) is one of the rarest pine species in the world. Restricted to one mainland and one island population in California, Torrey pine is a species of conservation concern under threat due to low population sizes, lack of genetic variation, and environmental stochasticity. Previous research points to a lack of within population variation that is...

Phenotypic selection varies with pollination intensity across populations of Sabatia angularis.

PubMed

Emel, Sarah L; Franks, Steven J; Spigler, Rachel B

2017-07-01

Pollinators are considered primary selective agents acting on plant traits, and thus variation in the strength of the plant-pollinator interaction might drive variation in the opportunity for selection and selection intensity across plant populations. Here, we examine whether these critical evolutionary parameters covary with pollination intensity across wild populations of the biennial Sabatia angularis. We quantified pollination intensity in each of nine S. angularis populations as mean stigmatic pollen load per population. For female fitness and three components, fruit number, fruit set (proportion of flowers setting fruit) and number of seeds per fruit, we evaluated whether the opportunity for selection varied with pollination intensity. We used phenotypic selection analyses to test for interactions between pollination intensity and selection gradients for five floral traits, including flowering phenology. The opportunity for selection via fruit set and seeds per fruit declined significantly with increasing pollen receipt, as expected. We demonstrated significant directional selection on multiple traits across populations. We also found that selection intensity for all traits depended on pollination intensity. Consistent with general theory about the relationship between biotic interaction strength and the intensity of selection, our study suggests that variation in pollination intensity drives variation in selection across S. angularis populations. © 2017 The Authors. New Phytologist © 2017 New Phytologist Trust.

Genetic Variation and Geographic Differentiation Among Populations of the Nonmigratory Agricultural Pest Oedaleus infernalis (Orthoptera: Acridoidea) in China

PubMed Central

Sun, Wei; Dong, Hui; Gao, Yue-Bo; Su, Qian-Fu; Qian, Hai-Tao; Bai, Hong-Yan; Zhang, Zhu-Ting; Cong, Bin

2015-01-01

The nonmigratory grasshopper Oedaleus infernalis Saussure (Orthoptera : Acridoidea) is an agricultural pest to crops and forage grasses over a wide natural geographical distribution in China. The genetic diversity and genetic variation among 10 geographically separated populations of O. infernalis was assessed using polymerase chain reaction-based molecular markers, including the intersimple sequence repeat and mitochondrial cytochrome oxidase sequences. A high level of genetic diversity was detected among these populations from the intersimple sequence repeat (H: 0.2628, I: 0.4129, Hs: 0.2130) and cytochrome oxidase analyses (Hd: 0.653). There was no obvious geographical structure based on an unweighted pair group method analysis and median-joining network. The values of FST, θII, and Gst estimated in this study are low, and the gene flow is high (Nm > 4). Analysis of the molecular variance suggested that most of the genetic variation occurs within populations, whereas only a small variation takes place between populations. No significant correlation was found between the genetic distance and geographical distance. Overall, our results suggest that the geographical distance plays an unimpeded role in the gene flow among O. infernalis populations. PMID:26496789

Lotka-Volterra system in a random environment.

PubMed

Dimentberg, Mikhail F

2002-03-01

Classical Lotka-Volterra (LV) model for oscillatory behavior of population sizes of two interacting species (predator-prey or parasite-host pairs) is conservative. This may imply unrealistically high sensitivity of the system's behavior to environmental variations. Thus, a generalized LV model is considered with the equation for preys' reproduction containing the following additional terms: quadratic "damping" term that accounts for interspecies competition, and term with white-noise random variations of the preys' reproduction factor that simulates the environmental variations. An exact solution is obtained for the corresponding Fokker-Planck-Kolmogorov equation for stationary probability densities (PDF's) of the population sizes. It shows that both population sizes are independent gamma-distributed stationary random processes. Increasing level of the environmental variations does not lead to extinction of the populations. However it may lead to an intermittent behavior, whereby one or both population sizes experience very rare and violent short pulses or outbreaks while remaining on a very low level most of the time. This intermittency is described analytically by direct use of the solutions for the PDF's as well as by applying theory of excursions of random functions and by predicting PDF of peaks in the predators' population size.

Lotka-Volterra system in a random environment

NASA Astrophysics Data System (ADS)

Dimentberg, Mikhail F.

2002-03-01

Classical Lotka-Volterra (LV) model for oscillatory behavior of population sizes of two interacting species (predator-prey or parasite-host pairs) is conservative. This may imply unrealistically high sensitivity of the system's behavior to environmental variations. Thus, a generalized LV model is considered with the equation for preys' reproduction containing the following additional terms: quadratic ``damping'' term that accounts for interspecies competition, and term with white-noise random variations of the preys' reproduction factor that simulates the environmental variations. An exact solution is obtained for the corresponding Fokker-Planck-Kolmogorov equation for stationary probability densities (PDF's) of the population sizes. It shows that both population sizes are independent γ-distributed stationary random processes. Increasing level of the environmental variations does not lead to extinction of the populations. However it may lead to an intermittent behavior, whereby one or both population sizes experience very rare and violent short pulses or outbreaks while remaining on a very low level most of the time. This intermittency is described analytically by direct use of the solutions for the PDF's as well as by applying theory of excursions of random functions and by predicting PDF of peaks in the predators' population size.

Genetic Structure of First Nation Communities in the Pacific Northwest.

PubMed

Hughes, Cris E; Rogers, Mary P; Owings, Amanda C; Petzelt, Barbara; Mitchell, Joycelynn; Harry, Harold; Williams, Theresa; Goldberg, Dena; Labuda, Damian; Smith, David Glenn; Cybulski, Jerome S; Malhi, Ripan S

2016-10-01

This study presents genetic data for nine Native American populations from northern North America. Analyses of genetic variation focus on the Pacific Northwest (PNW). Using mitochondrial, Y chromosomal, and autosomal DNA variants, we aimed to more closely address the relationships of geography and language with present genetic diversity among the regional PNW Native American populations. Patterns of genetic diversity exhibited by the three genetic systems were consistent with our hypotheses: genetic variation was more strongly explained by geographic proximity than by linguistic structure. Our findings were corroborated through a variety on analytic approaches, with the unrooted trees for the three genetic systems consistently separating inland from coastal PNW populations. Furthermore, analyses of molecular variance support the trends exhibited by the unrooted trees, with geographic partitioning of PNW populations (F CT = 19.43%, p = 0.010 ± 0.009) accounting for over twice as much of the observed genetic variation as linguistic partitioning of the same populations (F CT = 9.15%, p = 0.193 ± 0.013). These findings demonstrate a consensus with previous PNW population studies examining the relationships of genome-wide variation, mitochondrial haplogroup frequencies, and skeletal morphology with geography and language.

The role of sexual selection and conflict in mediating among-population variation in mating strategies and sexually dimorphic traits in Sepsis punctum.

PubMed

Dmitriew, Caitlin; Blanckenhorn, Wolf U

2012-01-01

The black scavenger fly Sepsis punctum exhibits striking among-population variation in the direction and magnitude of sexual size dimorphism, modification to the male forelimb and pre-copulatory behaviour. In some populations, male-biased sexual size dimorphism is observed; in other, less dimorphic, populations males court prior to mating. Such variation in reproductive traits is of interest to evolutionary biologists because it has the potential to limit gene flow among populations, contributing to speciation. Here, we investigate whether large male body size and modified forefemur are associated with higher male mating success within populations, whether these traits are associated with higher mating success among populations, and if these traits carry viability costs that could constrain their response to sexual selection. Flies from five distinct populations were reared at high or low food, generating high and low quality males. The expression of body size, forelimb morphology and courtship rate were each greater at high food, but high food males experienced higher mating success or reduced latency to first copulation in only one of the populations. Among populations, overall mating success increased with the degree of male-bias in overall body size and forelimb modification, suggesting that these traits have evolved as a means of increasing male mating rate. The increased mating success observed in large-male populations raises the question of why variation in magnitude of dimorphism persists among populations. One reason may be that costs of producing a large size constrain the evolution of ever-larger males. We found no evidence that juvenile mortality under food stress was greater for large-male populations, but development time was considerably longer and may represent an important constraint in an ephemeral and competitive growth environment.

Genome-wide single nucleotide polymorphisms reveal population history and adaptive divergence in wild guppies.

PubMed

Willing, Eva-Maria; Bentzen, Paul; van Oosterhout, Cock; Hoffmann, Margarete; Cable, Joanne; Breden, Felix; Weigel, Detlef; Dreyer, Christine

2010-03-01

Adaptation of guppies (Poecilia reticulata) to contrasting upland and lowland habitats has been extensively studied with respect to behaviour, morphology and life history traits. Yet population history has not been studied at the whole-genome level. Although single nucleotide polymorphisms (SNPs) are the most abundant form of variation in many genomes and consequently very informative for a genome-wide picture of standing natural variation in populations, genome-wide SNP data are rarely available for wild vertebrates. Here we use genetically mapped SNP markers to comprehensively survey genetic variation within and among naturally occurring guppy populations from a wide geographic range in Trinidad and Venezuela. Results from three different clustering methods, Neighbor-net, principal component analysis (PCA) and Bayesian analysis show that the population substructure agrees with geographic separation and largely with previously hypothesized patterns of historical colonization. Within major drainages (Caroni, Oropouche and Northern), populations are genetically similar, but those in different geographic regions are highly divergent from one another, with some indications of ancient shared polymorphisms. Clear genomic signatures of a previous introduction experiment were seen, and we detected additional potential admixture events. Headwater populations were significantly less heterozygous than downstream populations. Pairwise F(ST) values revealed marked differences in allele frequencies among populations from different regions, and also among populations within the same region. F(ST) outlier methods indicated some regions of the genome as being under directional selection. Overall, this study demonstrates the power of a genome-wide SNP data set to inform for studies on natural variation, adaptation and evolution of wild populations.

Genetic variation and evolution of Polaskia chichipe (Cactaceae) under domestication in the Tehuacán Valley, central Mexico.

PubMed

Otero-Arnaiz, Adriana; Casas, Alejandro; Hamrick, James L; Cruse-Sanders, Jennifer

2005-05-01

Polaskia chichipe is a columnar cactus under artificial selection in central Mexico because of its edible fruits. Our study explored the effect of human manipulation on levels and distribution of genetic variation in wild, silviculturally managed and cultivated sympatric populations. Total genetic variation, estimated in nine populations with five microsatellite loci, was H(T) = 0.658 +/- 0.026 SE, which was mainly distributed within populations (H(S) = 0.646) with low differentiation among them (F(ST) = 0.015). Fixation index (F(IS)) in all populations was positive, indicating a deficit of heterozygous individuals with respect to Hardy-Weinberg expectations. When populations were pooled by management type, the highest expected heterozygosity (H(E) = 0.631 +/- 0.031 SE) and the lowest fixation index (F(IS) = 0.07) were observed in wild populations, followed by cultivated populations (H(E) = 0.56 +/- 0.03 SE, F(IS) = 0.14), whereas the lowest variation was found in silviculturally managed populations (H(E) = 0.51 +/- 0.05 SE, F(IS) = 0.17). Low differentiation among populations under different management types (F(ST) 0.005, P < 0.04) was observed. A pattern of migration among neighbouring populations, suggested from isolation by distance (r2 = 0.314, P < 0.01), may have contributed to homogenizing populations and counteracting the effects of artificial selection. P. chichipe, used and managed for at least 700 generations, shows morphological differentiation, changes in breeding system and seed germination patterns associated with human management, with only slight genetic differences detected by neutral markers.

Variation in inpatient hospital prices and outpatient service quantities drive geographic differences in private spending in Texas.

PubMed

Franzini, Luisa; White, Chapin; Taychakhoonavudh, Suthira; Parikh, Rohan; Zezza, Mark; Mikhail, Osama

2014-12-01

To measure the contribution of market-level prices, utilization, and health risk to medical spending variation among the Blue Cross Blue Shield of Texas (BCBSTX) privately insured population and the Texas Medicare population. Claims data for all BCBSTX members and publicly available CMS data for Texas in 2011. We used observational data and decomposed overall and service-specific spending into health status and health status adjusted utilization and input prices and input prices adjusted for the BCBSTX and Medicare populations. Variation in overall BCBSTX spending across HRRs appeared driven by price variation, whereas utilization variation factored more prominently in Medicare. The contribution of price to spending variation differed by service category. Price drove inpatient spending variation, while utilization drove outpatient and professional spending variation in BCBSTX. The context in which negotiations occur may help explain the patterns across services. The conventional wisdom that Medicare does a better job of controlling prices and private plans do a better job of controlling volume is an oversimplification. BCBSTX does a good job of controlling outpatient and professional prices, but not at controlling inpatient prices. Strategies to manage the variation in spending may need to differ substantially depending on the service and payer. © Health Research and Educational Trust.

Variation in Inpatient Hospital Prices and Outpatient Service Quantities Drive Geographic Differences in Private Spending in Texas

PubMed Central

Franzini, Luisa; White, Chapin; Taychakhoonavudh, Suthira; Parikh, Rohan; Zezza, Mark; Mikhail, Osama

2014-01-01

Objective To measure the contribution of market-level prices, utilization, and health risk to medical spending variation among the Blue Cross Blue Shield of Texas (BCBSTX) privately insured population and the Texas Medicare population. Data Sources Claims data for all BCBSTX members and publicly available CMS data for Texas in 2011. Study Design We used observational data and decomposed overall and service-specific spending into health status and health status adjusted utilization and input prices and input prices adjusted for the BCBSTX and Medicare populations. Principal Findings Variation in overall BCBSTX spending across HRRs appeared driven by price variation, whereas utilization variation factored more prominently in Medicare. The contribution of price to spending variation differed by service category. Price drove inpatient spending variation, while utilization drove outpatient and professional spending variation in BCBSTX. The context in which negotiations occur may help explain the patterns across services. Conclusions The conventional wisdom that Medicare does a better job of controlling prices and private plans do a better job of controlling volume is an oversimplification. BCBSTX does a good job of controlling outpatient and professional prices, but not at controlling inpatient prices. Strategies to manage the variation in spending may need to differ substantially depending on the service and payer. PMID:24919408