WorldWideScience

Sample records for evolutionary distant temporal

  1. Realigning thunder and lightning: temporal adaptation to spatiotemporally distant events.

    Directory of Open Access Journals (Sweden)

    Jordi Navarra

    Full Text Available The brain is able to realign asynchronous signals that approximately coincide in both space and time. Given that many experience-based links between visual and auditory stimuli are established in the absence of spatiotemporal proximity, we investigated whether or not temporal realignment arises in these conditions. Participants received a 3-min exposure to visual and auditory stimuli that were separated by 706 ms and appeared either from the same (Experiment 1 or from different spatial positions (Experiment 2. A simultaneity judgment task (SJ was administered right afterwards. Temporal realignment between vision and audition was observed, in both Experiment 1 and 2, when comparing the participants' SJs after this exposure phase with those obtained after a baseline exposure to audiovisual synchrony. However, this effect was present only when the visual stimuli preceded the auditory stimuli during the exposure to asynchrony. A similar pattern of results (temporal realignment after exposure to visual-leading asynchrony but not after exposure to auditory-leading asynchrony was obtained using temporal order judgments (TOJs instead of SJs (Experiment 3. Taken together, these results suggest that temporal recalibration still occurs for visual and auditory stimuli that fall clearly outside the so-called temporal window for multisensory integration and appear from different spatial positions. This temporal realignment may be modulated by long-term experience with the kind of asynchrony (vision-leading that we most frequently encounter in the outside world (e.g., while perceiving distant events.

  2. Critical factors in the empirical performance of temporal difference and evolutionary methods for reinforcement learning

    NARCIS (Netherlands)

    Whiteson, S.; Taylor, M.E.; Stone, P.

    2010-01-01

    Temporal difference and evolutionary methods are two of the most common approaches to solving reinforcement learning problems. However, there is little consensus on their relative merits and there have been few empirical studies that directly compare their performance. This article aims to address

  3. Evolution in the block: common elements of 5S rDNA organization and evolutionary patterns in distant fish genera.

    Science.gov (United States)

    Campo, Daniel; García-Vázquez, Eva

    2012-01-01

    The 5S rDNA is organized in the genome as tandemly repeated copies of a structural unit composed of a coding sequence plus a nontranscribed spacer (NTS). The coding region is highly conserved in the evolution, whereas the NTS vary in both length and sequence. It has been proposed that 5S rRNA genes are members of a gene family that have arisen through concerted evolution. In this study, we describe the molecular organization and evolution of the 5S rDNA in the genera Lepidorhombus and Scophthalmus (Scophthalmidae) and compared it with already known 5S rDNA of the very different genera Merluccius (Merluccidae) and Salmo (Salmoninae), to identify common structural elements or patterns for understanding 5S rDNA evolution in fish. High intra- and interspecific diversity within the 5S rDNA family in all the genera can be explained by a combination of duplications, deletions, and transposition events. Sequence blocks with high similarity in all the 5S rDNA members across species were identified for the four studied genera, with evidences of intense gene conversion within noncoding regions. We propose a model to explain the evolution of the 5S rDNA, in which the evolutionary units are blocks of nucleotides rather than the entire sequences or single nucleotides. This model implies a "two-speed" evolution: slow within blocks (homogenized by recombination) and fast within the gene family (diversified by duplications and deletions).

  4. Distant Relations

    DEFF Research Database (Denmark)

    Søndergaard, Morten

    2011-01-01

    Art EntrepreneurshipIvo Zander Mikael Scherdin This project is funded and sponsored by the Knowledge Foundation, the Bank of Sweden Tercentenary Foundation, and the Department of Business Studies, Uppsala University2008-2009This cutting edge project asks what art and artistic processes can contri......) Entrepreneurship on the art arena - An ecological perspective (Mikael Scherdin and Ivo Zander) Distant relations - Art practice in a global culture (Morten Søndergaard) Art entrepreneurship - A commentary (Daved Barry) Summary and policy implications (Mikael Scherdin and Ivo Zander)...

  5. Maintenance of genetic variation in human personality: Testing evolutionary models by estimating heritability due to common causal variants and investigating the effect of distant inbreeding

    Science.gov (United States)

    Verweij, Karin J.H.; Yang, Jian; Lahti, Jari; Veijola, Juha; Hintsanen, Mirka; Pulkki-Råback, Laura; Heinonen, Kati; Pouta, Anneli; Pesonen, Anu-Katriina; Widen, Elisabeth; Taanila, Anja; Isohanni, Matti; Miettunen, Jouko; Palotie, Aarno; Penke, Lars; Service, Susan K.; Heath, Andrew C.; Montgomery, Grant W.; Raitakari, Olli; Kähönen, Mika; Viikari, Jorma; Räikkönen, Katri; Eriksson, Johan G; Keltikangas-Järvinen, Liisa; Lehtimäki, Terho; Martin, Nicholas G.; Järvelin, Marjo-Riitta; Visscher, Peter M.; Keller, Matthew C.; Zietsch, Brendan P.

    2012-01-01

    Personality traits are basic dimensions of behavioural variation, and twin, family, and adoption studies show that around 30% of the between-individual variation is due to genetic variation. There is rapidly-growing interest in understanding the evolutionary basis of this genetic variation. Several evolutionary mechanisms could explain how genetic variation is maintained in traits, and each of these makes predictions in terms of the relative contribution of rare and common genetic variants to personality variation, the magnitude of nonadditive genetic influences, and whether personality is affected by inbreeding. Using genome-wide SNP data from >8,000 individuals, we estimated that little variation in the Cloninger personality dimensions (7.2% on average) is due to the combined effect of common, additive genetic variants across the genome, suggesting that most heritable variation in personality is due to rare variant effects and/or a combination of dominance and epistasis. Furthermore, higher levels of inbreeding were associated with less socially-desirable personality trait levels in three of the four personality dimensions. These findings are consistent with genetic variation in personality traits having been maintained by mutation-selection balance. PMID:23025612

  6. Simulating Spatio-Temporal Slip Evolution of Fault Zones at Different Evolutionary Stages

    Science.gov (United States)

    Hillers, G.; Mai, M.; Ben-Zion, Y.

    2004-12-01

    Previous studies of spatio-temporal evolution of slip on a fault governed by rate-and-state friction (e.g., Rice, 1993; Ben-Zion and Rice, 1995, 1997; Tullis, 1996; Lapusta et al., 2000) employed frictional properties corresponding to fairly homogeneous faults. In most cases, the only types of heterogeneities were the lab-based depth-variations of the parameters a and b that produce transitions between stable velocity-strengthening and unstable velocity-weakening regimes. In this study we use a constant a-b profile and a depth-dependent distribution of the critical slip distance parameter L. In addition, correlated heterogeneities of L along strike are used to model geometrical heterogeneities on faults related to roughness. More specifically, we will perform 3D quasi-static and quasi-dynamic simulations of slip on a strike-slip fault using a family of 2D anisotropic correlated distributions of L having different correlation lengths along strike and downdip. The depth-variation of L over the depth range 3km histories. The 3D code with various cases of anisotropic correlated distributions of L will be used to study many issues related to observed complex behavior of seismogenic faults including: (1) Nucleation and arrest properties of failure episodes on a heterogeneous fault governed by RSD friction. (2) Comparison between properties of final simulated slip histories and those of the inverted slip histories. (3) Frequency-size and temporal statistics of simulated earthquakes on a heterogeneous fault governed by rate-and-state friction.

  7. The evolutionary origins of human patience: temporal preferences in chimpanzees, bonobos, and human adults.

    Science.gov (United States)

    Rosati, Alexandra G; Stevens, Jeffrey R; Hare, Brian; Hauser, Marc D

    2007-10-09

    To make adaptive choices, individuals must sometimes exhibit patience, forgoing immediate benefits to acquire more valuable future rewards [1-3]. Although humans account for future consequences when making temporal decisions [4], many animal species wait only a few seconds for delayed benefits [5-10]. Current research thus suggests a phylogenetic gap between patient humans and impulsive, present-oriented animals [9, 11], a distinction with implications for our understanding of economic decision making [12] and the origins of human cooperation [13]. On the basis of a series of experimental results, we reject this conclusion. First, bonobos (Pan paniscus) and chimpanzees (Pan troglodytes) exhibit a degree of patience not seen in other animals tested thus far. Second, humans are less willing to wait for food rewards than are chimpanzees. Third, humans are more willing to wait for monetary rewards than for food, and show the highest degree of patience only in response to decisions about money involving low opportunity costs. These findings suggest that core components of the capacity for future-oriented decisions evolved before the human lineage diverged from apes. Moreover, the different levels of patience that humans exhibit might be driven by fundamental differences in the mechanisms representing biological versus abstract rewards.

  8. Limited Spatial and Temporal Variability in Meiofauna and Nematode Communities at Distant but Environmentally Similar Sites in an Area of Interest for Deep-Sea Mining

    Directory of Open Access Journals (Sweden)

    Ellen Pape

    2017-06-01

    Full Text Available To be able to adequately assess potential environmental impacts of deep-sea polymetallic nodule mining, the establishment of a proper environmental baseline, incorporating both spatial and temporal variability, is essential. The aim of the present study was to evaluate both spatial and intra-annual variability in meiofauna (higher taxa and nematode communities (families and genera, and Halalaimus species within the license area of Global Sea mineral Resources (GSR in the northeastern Clarion Clipperton Fracture Zone (CCFZ, and to determine the efficiency of the current sampling of meiofauna and nematode diversity. In October 2015, three polymetallic nodule-bearing sites, about 60–270 km apart, located at similar depths (ca. 4,500 m were sampled, of which one site was sampled in April in that same year. Despite the relatively large geographical distances and the statistically significant, but small, differences in sedimentary characteristics between sites, meiofauna and nematode communities were largely similar in terms of abundance, composition and diversity. Between-site differences in community composition were mainly driven by a set of rare and less abundant taxa. Moreover, although surface primary productivity in April exceeded that in October, no significant changes were observed in sedimentary characteristics or in meiofauna and nematode communities. At all sites and in both periods, Nematoda were the prevailing meiofaunal phylum, which was in turn dominated by Monhysterid genera and Acantholaimus. Our findings support the earlier purported notion of a low degree of endemism for nematode genera and meiofauna taxa in the deep sea, and hint at the possibility of large distribution ranges for at least some Halalaimus species. Taxon richness estimators revealed that the current sampling design was able to characterize the majority of the meiofauna and nematode taxa present. To conclude, implications of the present findings for environmental

  9. Evolutionary macroecology

    Directory of Open Access Journals (Sweden)

    José Alexandre F. Diniz-Filho

    2013-10-01

    Full Text Available Macroecology focuses on ecological questions at broad spatial and temporal scales, providing a statistical description of patterns in species abundance, distribution and diversity. More recently, historical components of these patterns have begun to be investigated more deeply. We tentatively refer to the practice of explicitly taking species history into account, both analytically and conceptually, as ‘evolutionary macroecology’. We discuss how the evolutionary dimension can be incorporated into macroecology through two orthogonal and complementary data types: fossils and phylogenies. Research traditions dealing with these data have developed more‐or‐less independently over the last 20–30 years, but merging them will help elucidate the historical components of diversity gradients and the evolutionary dynamics of species’ traits. Here we highlight conceptual and methodological advances in merging these two research traditions and review the viewpoints and toolboxes that can, in combination, help address patterns and unveil processes at temporal and spatial macro‐scales.

  10. Evolutionary dynamics and temporal/geographical correlates of recombination in the human enterovirus echovirus types 9, 11, and 30.

    Science.gov (United States)

    McWilliam Leitch, E C; Cabrerizo, M; Cardosa, J; Harvala, H; Ivanova, O E; Kroes, A C M; Lukashev, A; Muir, P; Odoom, J; Roivainen, M; Susi, P; Trallero, G; Evans, D J; Simmonds, P

    2010-09-01

    The relationship between virus evolution and recombination in species B human enteroviruses was investigated through large-scale genetic analysis of echovirus type 9 (E9) and E11 isolates (n = 85 and 116) from 16 European, African, and Asian countries between 1995 and 2008. Cluster 1 E9 isolates and genotype D5 and A E11 isolates showed evidence of frequent recombination between the VP1 and 3Dpol regions, the latter falling into 23 (E9) and 43 (E11) clades interspersed phylogenetically with 46 3Dpol clades of E30 and with those of other species B serotypes. Remarkably, only 2 of the 112 3Dpol clades were shared by more than one serotype (E11 and E30), demonstrating an extremely large and genetically heterogeneous recombination pool of species B nonstructural-region variants. The likelihood of recombination increased with geographical separation and time, and both were correlated with VP1 divergence, whose substitution rates allowed recombination half-lives of 1.3, 9.8, and 3.1 years, respectively, for E9, E11, and E30 to be calculated. These marked differences in recombination dynamics matched epidemiological patterns of periodic epidemic cycles of 2 to 3 (E9) and 5 to 6 (E30) years and the longer-term endemic pattern of E11 infections. Phylotemporal analysis using a Bayesian Markov chain Monte Carlo method, which placed recombination events within the evolutionary reconstruction of VP1, showed a close relationship with VP1 lineage expansion, with defined recombination events that correlated with their epidemiological periodicity. Whether recombination events contribute directly to changes in transmissibility that drive epidemic behavior or occur stochastically during periodic population bottlenecks is an unresolved issue vital to future understanding of enterovirus molecular epidemiology and pathogenesis.

  11. Evolutionary Dynamics and Temporal/Geographical Correlates of Recombination in the Human Enterovirus Echovirus Types 9, 11, and 30▿

    Science.gov (United States)

    McWilliam Leitch, E. C.; Cabrerizo, M.; Cardosa, J.; Harvala, H.; Ivanova, O. E.; Kroes, A. C. M.; Lukashev, A.; Muir, P.; Odoom, J.; Roivainen, M.; Susi, P.; Trallero, G.; Evans, D. J.; Simmonds, P.

    2010-01-01

    The relationship between virus evolution and recombination in species B human enteroviruses was investigated through large-scale genetic analysis of echovirus type 9 (E9) and E11 isolates (n = 85 and 116) from 16 European, African, and Asian countries between 1995 and 2008. Cluster 1 E9 isolates and genotype D5 and A E11 isolates showed evidence of frequent recombination between the VP1 and 3Dpol regions, the latter falling into 23 (E9) and 43 (E11) clades interspersed phylogenetically with 46 3Dpol clades of E30 and with those of other species B serotypes. Remarkably, only 2 of the 112 3Dpol clades were shared by more than one serotype (E11 and E30), demonstrating an extremely large and genetically heterogeneous recombination pool of species B nonstructural-region variants. The likelihood of recombination increased with geographical separation and time, and both were correlated with VP1 divergence, whose substitution rates allowed recombination half-lives of 1.3, 9.8, and 3.1 years, respectively, for E9, E11, and E30 to be calculated. These marked differences in recombination dynamics matched epidemiological patterns of periodic epidemic cycles of 2 to 3 (E9) and 5 to 6 (E30) years and the longer-term endemic pattern of E11 infections. Phylotemporal analysis using a Bayesian Markov chain Monte Carlo method, which placed recombination events within the evolutionary reconstruction of VP1, showed a close relationship with VP1 lineage expansion, with defined recombination events that correlated with their epidemiological periodicity. Whether recombination events contribute directly to changes in transmissibility that drive epidemic behavior or occur stochastically during periodic population bottlenecks is an unresolved issue vital to future understanding of enterovirus molecular epidemiology and pathogenesis. PMID:20610722

  12. Global analysis of population structure, spatial and temporal dynamics of genetic diversity, and evolutionary lineages of Iris yellow spot virus (Tospovirus: Bunyaviridae).

    Science.gov (United States)

    Iftikhar, Romana; Ramesh, Shunmugiah V; Bag, Sudeep; Ashfaq, Muhammad; Pappu, Hanu R

    2014-08-15

    Thrips-transmitted Iris yellow spot virus is an economically important viral pathogen of Allium crops worldwide. A global analysis of known IYSV nucleocapsid gene (N gene) sequences was carried out to determine the comparative population structure, spatial and temporal dynamics with reference to its genetic diversity and evolution. A total of 98 complete N gene sequences (including 8 sequences reported in this study) available in GenBank and reported from 23 countries were characterized by in-silico RFLP analysis. Based on RFLP, 94% of the isolates could be grouped into NL or BR types while the rest belonged to neither group. The relative proportion of NL and BR types was 46% and 48%, respectively. A temporal shift in the IYSV genotypes with a greater incremental incidence of IYSVBR was found over IYSVNL before 2005 compared to after 2005. The virus population had at least one evolutionarily significant recombination event, involving IYSVBR and IYSVNL. Codon substitution studies did not identify any significant differences among the genotypes of IYSV. However, N gene codons were minimally positively selected, moderately negatively selected denoting the action of purifying selection, thus rejecting the theory of neutral mutation in IYSV population. However, one codon position (139) was found to be positively selected in all the genotypes. Population selection statistics in the IYSVBR, IYSVNL genotypes and in the population as a whole also revealed the action of purifying selection or population expansion, whereas IYSVother displayed a decrease in population size. Genetic differentiation studies showed inherent differentiation and infrequent gene flow between IYSVBR and IYSVNL genotypes corroborating the geographical confinement of these genotypes. Taken together the study suggests that the observed diversity in IYSV population and temporal shift in IYSVBR genotype is attributable to genetic recombination, abundance of purifying selection, insignificant positive

  13. Distant relationships amongst protein domains

    Indian Academy of Sciences (India)

    ncbs

    Concept of distant relationships. ○ Objective method for identification of structural motifs. ○ Computer algorithms and servers that employ structural motifs .... Assessment of a rigorous transitive cascaded sequence search procedure for enhanced remote homology detection. S. Sandhya, S. Chakrabarti, K. Abhinandan, N.

  14. Galactic Teamwork Makes Distant Bubbles

    Science.gov (United States)

    Kohler, Susanna

    2016-03-01

    During the period of reionization that followed the dark ages of our universe, hydrogen was transformed from a neutral state, which is opaque to radiation, to an ionized one, which is transparent to radiation. But what generated the initial ionizing radiation? The recent discovery of multiple distant galaxies offers evidence for how this process occurred.Two Distant GalaxiesWe believe reionization occurred somewhere between a redshift of z = 6 and 7, because Ly-emitting galaxies drop out at roughly this redshift. Beyond this distance, were generally unable to see the light from these galaxies, because the universe is no longer transparent to their emission. This is not always the case, however: if a bubble of ionized gas exists around a distant galaxy, the radiation can escape, allowing us to see the galaxy.This is true of two recently-discovered Ly-emitting galaxies, confirmed to be at a redshift of z~7 and located near one another in a region known as the Bremer Deep Field. The fact that were able to see the radiation from these galaxies means that they are in an ionized HII region presumably one of the earlier regions to have become reionized in the universe.But on their own, neither of these galaxies is capable of generating an ionized bubble large enough for their light to escape. So what ionized the region around them, and what does this mean for our understanding of how reionization occurred in the universe?A Little Help From FriendsLocation in different filters of the objects in the Hubble Bremer Deep Field catalog. The z~7 selection region is outlined by the grey box. BDF-521 and BDF-3299 were the two originally discovered galaxies; the remaining red markers indicate the additional six galaxies discovered in the same region. [Castellano et al. 2016]A team of scientists led by Marco Castellano (Rome Observatory, INAF) investigated the possibility that there are other, faint galaxies near these two that have helped to ionize the region. Performing a survey

  15. Identity disturbance in distant patients.

    Science.gov (United States)

    Hoffman, Irwin

    2013-04-01

    Chronically distant, emotionally isolated patients often present with identity disturbance. Identity, it is argued, develops as a thematic pattern of narcissism, shaped by the nature of the mother's early libidinal influences on the child's sense of self. Identity provides a form of self-definition that addresses the question, Who am I? In the treatment of these patients, resistances to narcissistic vulnerabilities (narcissistic resistances) provide an illusory sense of security and induce the analyst to avoid attention to a central pathological problem: primitive and frightening needs for, and unconscious fantasies of, dependence on, and functionality for, another. Patients' avoidance of material and therapeutic interactions that deal with their dependencies are aspects of a tacit contract with the analyst to foreclose examination of their considerable problems with inner stability. Among these problems are anxieties regarding intrusion and loss of separateness. As analysis proceeds, elements of such a patient's identity become clarified and are used to understand and organize the material for both analyst and patient. This can allow the patient to articulate a more embodied and vital experience of individuality. A case is presented to illustrate the analysis of a patient using this approach.

  16. Evolutionary Nephrology.

    Science.gov (United States)

    Chevalier, Robert L

    2017-05-01

    Progressive kidney disease follows nephron loss, hyperfiltration, and incomplete repair, a process described as "maladaptive." In the past 20 years, a new discipline has emerged that expands research horizons: evolutionary medicine. In contrast to physiologic (homeostatic) adaptation, evolutionary adaptation is the result of reproductive success that reflects natural selection. Evolutionary explanations for physiologically maladaptive responses can emerge from mismatch of the phenotype with environment or evolutionary tradeoffs. Evolutionary adaptation to a terrestrial environment resulted in a vulnerable energy-consuming renal tubule and a hypoxic, hyperosmolar microenvironment. Natural selection favors successful energy investment strategy: energy is allocated to maintenance of nephron integrity through reproductive years, but this declines with increasing senescence after ~40 years of age. Risk factors for chronic kidney disease include restricted fetal growth or preterm birth (life history tradeoff resulting in fewer nephrons), evolutionary selection for APOL1 mutations (that provide resistance to trypanosome infection, a tradeoff), and modern life experience (Western diet mismatch leading to diabetes and hypertension). Current advances in genomics, epigenetics, and developmental biology have revealed proximate causes of kidney disease, but attempts to slow kidney disease remain elusive. Evolutionary medicine provides a complementary approach by addressing ultimate causes of kidney disease. Marked variation in nephron number at birth, nephron heterogeneity, and changing susceptibility to kidney injury throughout life history are the result of evolutionary processes. Combined application of molecular genetics, evolutionary developmental biology (evo-devo), developmental programming and life history theory may yield new strategies for prevention and treatment of chronic kidney disease.

  17. Temporal mortality-colonization dynamic can influence the coexistence and persistence patterns of cooperators and defectors in an evolutionary game model

    Directory of Open Access Journals (Sweden)

    YouHua Chen

    2014-03-01

    Full Text Available In the present report, the coexistence and persistence time patterns of Prisoners' Dilemma game players were explored in 2D spatial grid systems by considering the impacts of the mortality-colonization temporal dynamic specifically. Our results showed that the waiting time for triggering a colonization event could remarkably influence and change the extinction patterns of both cooperators and defectors. Interestingly, a relatively high frequency of stochastic colonization events could promote the persistence of defectors but not cooperators. In contrast, a low frequency of stochastic- or constant-time colonization events could facilitate the persistence of cooperators but not defectors. However, a long waiting time would be detrimental to the survival of both game players and drives them to go extinction in faster rates. At last, it was found that colonization strength played a relatively weak role on influencing the coexistence scenarios of both game players, but should be kept small if the coexistence of game players is needed to maintain. In conclusion, our study provides evidence showing that the temporal trade-off of mortality and colonization activities would influence the evolution of PD game and the persistence of cooperators and defectors.

  18. EVOLUTIONARY PERSPECTIVES IN A MUTUALISM OF SEPIOLID SQUID AND BIOLUMINESCENT BACTERIA: COMBINED USAGE OF MICROBIAL EXPERIMENTAL EVOLUTION AND TEMPORAL POPULATION GENETICS

    Science.gov (United States)

    Soto, W.; Punke, E. B.; Nishiguchi, M. K.

    2013-01-01

    The symbiosis between marine bioluminescent Vibrio bacteria and the sepiolid squid Euprymna is a model for studying animal–bacterial Interactions. Vibrio symbionts native to particular Euprymna species are competitively dominant, capable of outcompeting foreign Vibrio strains from other Euprymna host species. Despite competitive dominance, secondary colonization events by invading nonnative Vibrio fischeri have occurred. Competitive dominance can be offset through superior nonnative numbers and advantage of early start host colonization by nonnatives, granting nonnative vibrios an opportunity to establish beachheads in foreign Euprymna hosts. Here, we show that nonnative V. fischeri are capable of rapid adaptation to novel sepiolid squid hosts by serially passaging V. fischeri JRM200 (native to Hawaiian Euprymna scolopes) lines through the novel Australian squid host E. tasmanica for 500 generations. These experiments were complemented by a temporal population genetics survey of V. fischeri, collected from E. tasmanica over a decade, which provided a perspective from the natural history of V. fischeri evolution over 15,000–20,000 generations in E. tasmanica. No symbiont anagenic evolution within squids was observed, as competitive dominance does not purge V. fischeri genetic diversity through time. Instead, abiotic factors affecting abundance of V. fischeri variants in the planktonic phase sustain temporal symbiont diversity, a property itself of ecological constraints imposed by V. fischeri host adaptation. PMID:22519773

  19. Arming and firing system for DISTANT RUNNER

    Energy Technology Data Exchange (ETDEWEB)

    Skenandore, L.H.; Johnson, J.P.

    1982-03-01

    Sandia A and F systems Division 1132 provided arming and firing support for the DISTANT RUNNER Test Program at White Sands Missile Range. This report describes the field support and the firing system that was used.

  20. Evolutionary Nephrology

    Directory of Open Access Journals (Sweden)

    Robert L. Chevalier

    2017-05-01

    Full Text Available Progressive kidney disease follows nephron loss, hyperfiltration, and incomplete repair, a process described as “maladaptive.” In the past 20 years, a new discipline has emerged that expands research horizons: evolutionary medicine. In contrast to physiologic (homeostatic adaptation, evolutionary adaptation is the result of reproductive success that reflects natural selection. Evolutionary explanations for physiologically maladaptive responses can emerge from mismatch of the phenotype with environment or from evolutionary tradeoffs. Evolutionary adaptation to a terrestrial environment resulted in a vulnerable energy-consuming renal tubule and a hypoxic, hyperosmolar microenvironment. Natural selection favors successful energy investment strategy: energy is allocated to maintenance of nephron integrity through reproductive years, but this declines with increasing senescence after ∼40 years of age. Risk factors for chronic kidney disease include restricted fetal growth or preterm birth (life history tradeoff resulting in fewer nephrons, evolutionary selection for APOL1 mutations (which provide resistance to trypanosome infection, a tradeoff, and modern life experience (Western diet mismatch leading to diabetes and hypertension. Current advances in genomics, epigenetics, and developmental biology have revealed proximate causes of kidney disease, but attempts to slow kidney disease remain elusive. Evolutionary medicine provides a complementary approach by addressing ultimate causes of kidney disease. Marked variation in nephron number at birth, nephron heterogeneity, and changing susceptibility to kidney injury throughout the life history are the result of evolutionary processes. Combined application of molecular genetics, evolutionary developmental biology (evo-devo, developmental programming, and life history theory may yield new strategies for prevention and treatment of chronic kidney disease.

  1. Defining fitness in evolutionary models

    Indian Academy of Sciences (India)

    The analysis of evolutionary models requires an appropriate definition for fitness. In this paper, I review such definitions in relation to the five major dimensions by which models may be described, namely. finite versus infinite (or very large) population size,; type of environment (constant, fixed length, temporally stochastic, ...

  2. Evolutionary Awareness

    Directory of Open Access Journals (Sweden)

    Gregory Gorelik

    2014-10-01

    Full Text Available In this article, we advance the concept of “evolutionary awareness,” a metacognitive framework that examines human thought and emotion from a naturalistic, evolutionary perspective. We begin by discussing the evolution and current functioning of the moral foundations on which our framework rests. Next, we discuss the possible applications of such an evolutionarily-informed ethical framework to several domains of human behavior, namely: sexual maturation, mate attraction, intrasexual competition, culture, and the separation between various academic disciplines. Finally, we discuss ways in which an evolutionary awareness can inform our cross-generational activities—which we refer to as “intergenerational extended phenotypes”—by helping us to construct a better future for ourselves, for other sentient beings, and for our environment.

  3. Evolutionary Expectations

    DEFF Research Database (Denmark)

    Nash, Ulrik William

    2014-01-01

    cognitive bounds will perceive business opportunities identically. In addition, because cues provide information about latent causal structures of the environment, changes in causality must be accompanied by changes in cognitive representations if adaptation is to be maintained. The concept of evolutionary......, they are correlated among people who share environments because these individuals satisfice within their cognitive bounds by using cues in order of validity, as opposed to using cues arbitrarily. Any difference in expectations thereby arise from differences in cognitive ability, because two individuals with identical......The concept of evolutionary expectations descends from cue learning psychology, synthesizing ideas on rational expectations with ideas on bounded rationality, to provide support for these ideas simultaneously. Evolutionary expectations are rational, but within cognitive bounds. Moreover...

  4. [Evolutionary medicine].

    Science.gov (United States)

    Wjst, M

    2013-12-01

    Evolutionary medicine allows new insights into long standing medical problems. Are we "really stoneagers on the fast lane"? This insight might have enormous consequences and will allow new answers that could never been provided by traditional anthropology. Only now this is made possible using data from molecular medicine and systems biology. Thereby evolutionary medicine takes a leap from a merely theoretical discipline to practical fields - reproductive, nutritional and preventive medicine, as well as microbiology, immunology and psychiatry. Evolutionary medicine is not another "just so story" but a serious candidate for the medical curriculum providing a universal understanding of health and disease based on our biological origin. © Georg Thieme Verlag KG Stuttgart · New York.

  5. Receptor conversion in distant breast cancer metastases

    NARCIS (Netherlands)

    Hoefnagel, Laurien D. C.; van de Vijver, Marc J.; van Slooten, Henk-Jan; Wesseling, Pieter; Wesseling, Jelle; Westenend, Pieter J.; Bart, Joost; Seldenrijk, Cornelis A.; Nagtegaal, Iris D.; Oudejans, Joost; van der Valk, Paul; van der Groep, Petra; de Vries, Elisabeth G. E.; van der Wall, Elsken; van Diest, Paul J.

    2010-01-01

    Introduction: When breast cancer patients develop distant metastases, the choice of systemic treatment is usually based on tissue characteristics of the primary tumor as determined by immunohistochemistry (IHC) and/or molecular analysis. Several previous studies have shown that the immunophenotype

  6. Detection of cancer before distant metastasis

    NARCIS (Netherlands)

    Coumans, Frank A. W.; Siesling, Sabine; Terstappen, Leon W. M. M.

    2013-01-01

    Background: To establish a distant metastasis (DM) cells must disseminate from the primary tumor and overcome a series of obstacles, the metastatic cascade. In this study we develop a mathematical model for this cascade to estimate the tumor size and the circulating tumor cell (CTC) load before the

  7. Research traditions and evolutionary explanations in medicine.

    Science.gov (United States)

    Méthot, Pierre-Olivier

    2011-02-01

    In this article, I argue that distinguishing 'evolutionary' from 'Darwinian' medicine will help us assess the variety of roles that evolutionary explanations can play in a number of medical contexts. Because the boundaries of evolutionary and Darwinian medicine overlap to some extent, however, they are best described as distinct 'research traditions' rather than as competing paradigms. But while evolutionary medicine does not stand out as a new scientific field of its own, Darwinian medicine is united by a number of distinctive theoretical and methodological claims. For example, evolutionary medicine and Darwinian medicine can be distinguished with respect to the styles of evolutionary explanations they employ. While the former primarily involves 'forward looking' explanations, the latter depends mostly on 'backward looking' explanations. A forward looking explanation tries to predict the effects of ongoing evolutionary processes on human health and disease in contemporary environments (e.g., hospitals). In contrast, a backward looking explanation typically applies evolutionary principles from the vantage point of humans' distant biological past in order to assess present states of health and disease. Both approaches, however, are concerned with the prevention and control of human diseases. In conclusion, I raise some concerns about the claim that 'nothing in medicine makes sense except in the light of evolution'.

  8. Evolution of microgastropods (Ellobioidea, Carychiidae): integrating taxonomic, phylogenetic and evolutionary hypotheses.

    Science.gov (United States)

    Weigand, Alexander M; Jochum, Adrienne; Slapnik, Rajko; Schnitzler, Jan; Zarza, Eugenia; Klussmann-Kolb, Annette

    2013-01-23

    Current biodiversity patterns are considered largely the result of past climatic and tectonic changes. In an integrative approach, we combine taxonomic and phylogenetic hypotheses to analyze temporal and geographic diversification of epigean (Carychium) and subterranean (Zospeum) evolutionary lineages in Carychiidae (Eupulmonata, Ellobioidea). We explicitly test three hypotheses: 1) morphospecies encompass unrecognized evolutionary lineages, 2) limited dispersal results in a close genetic relationship of geographical proximally distributed taxa and 3) major climatic and tectonic events had an impact on lineage diversification within Carychiidae. Initial morphospecies assignments were investigated by different molecular delimitation approaches (threshold, ABGD, GMYC and SP). Despite a conservative delimitation strategy, carychiid morphospecies comprise a great number of unrecognized evolutionary lineages. We attribute this phenomenon to historic underestimation of morphological stasis and phenotypic variability amongst lineages. The first molecular phylogenetic hypothesis for the Carychiidae (based on COI, 16S and H3) reveals Carychium and Zospeum to be reciprocally monophyletic. Geographical proximally distributed lineages are often closely related. The temporal diversification of Carychiidae is best described by a constant rate model of diversification. The evolution of Carychiidae is characterized by relatively few (long distance) colonization events. We find support for an Asian origin of Carychium. Zospeum may have arrived in Europe before extant members of Carychium. Distantly related Carychium clades inhabit a wide spectrum of the available bioclimatic niche and demonstrate considerable niche overlap. Carychiid taxonomy is in dire need of revision. An inferred wide distribution and variable phenotype suggest underestimated diversity in Zospeum. Several Carychium morphospecies are results of past taxonomic lumping. By collecting populations at their type

  9. New views of the distant stellar halo

    Science.gov (United States)

    Sanderson, Robyn E.; Secunda, Amy; Johnston, Kathryn V.; Bochanski, John J.

    2017-10-01

    Currently, only a small number of Milky Way (MW) stars are known to exist beyond 100 kpc from the Galactic Centre. Though the distribution of these stars in the outer halo is believed to be sparse, they can provide evidence of more recent accretion events than in the inner halo and help map out the MW's dark matter halo to its virial radius. We have re-examined the outermost regions of 11 existing stellar halo models with two synthetic surveys: one mimicking present-day searches for distant M giants and another mimicking RR Lyra (RRL) projections for the Large Synoptic Survey Telescope (LSST). Our models suggest that colour and proper motion cuts currently used to select M giant candidates for follow-up successfully remove nearly all self-contamination from foreground halo dwarf stars and are useful for focusing observations on distant M giants, of which there are thousands to tens of thousands beyond 100 kpc in our models. We likewise expect that LSST will identify comparable numbers of RRLe at these distances. We demonstrate that several observable properties of both tracers, such as proximity of neighbouring stars, proper motions and distances (for RRLe), could help us separate different accreted dwarf galaxies from one another in the distant MW halo. We also discuss prospects for using ratios of M giants to RRLe as a proxy for accretion time, which in the future could provide new constraints on the recent accretion history of our Galaxy.

  10. Evolutionary institutionalism.

    Science.gov (United States)

    Fürstenberg, Dr Kai

    Institutions are hard to define and hard to study. Long prominent in political science have been two theories: Rational Choice Institutionalism (RCI) and Historical Institutionalism (HI). Arising from the life sciences is now a third: Evolutionary Institutionalism (EI). Comparative strengths and weaknesses of these three theories warrant review, and the value-to-be-added by expanding the third beyond Darwinian evolutionary theory deserves consideration. Should evolutionary institutionalism expand to accommodate new understanding in ecology, such as might apply to the emergence of stability, and in genetics, such as might apply to political behavior? Core arguments are reviewed for each theory with more detailed exposition of the third, EI. Particular attention is paid to EI's gene-institution analogy; to variation, selection, and retention of institutional traits; to endogeneity and exogeneity; to agency and structure; and to ecosystem effects, institutional stability, and empirical limitations in behavioral genetics. RCI, HI, and EI are distinct but complementary. Institutional change, while amenable to rational-choice analysis and, retrospectively, to criticaljuncture and path-dependency analysis, is also, and importantly, ecological. Stability, like change, is an emergent property of institutions, which tend to stabilize after change in a manner analogous to allopatric speciation. EI is more than metaphorically biological in that institutional behaviors are driven by human behaviors whose evolution long preceded the appearance of institutions themselves.

  11. Nearby Hot Stars May Change Our View of Distant Sources

    Science.gov (United States)

    Kohler, Susanna

    2017-07-01

    Nebula were thought to have formed only as the star evolved late into its lifetime, Walker and collaborators are now suggesting that all stars regardless of spectral type or evolutionary stage may be surrounded by swarms of tiny molecular clumps. Aroundstars that are hot enough, these clumps become the ionized plasma streamers that can cause interference with the light traveling to us from distant sources.Significant MassTo test this theory, Walker and collaborators explore observations of two distant radio quasars that have both exhibited intra-day variability over many years of observations. The team identified a hot A-type star near each of these two sources: J1819+3845 has Vega nearby, and PKS 1257326 has Alhakim.Locations of stars along the line of site to two distant quasars, J1819+3845 (top panel) and PKS 1257326 (bottom panel). Both have a nearby, hot star (blue markers) radially within 2 pc: Vega (z = 7.7 pc) and Alhakim (z = 18 pc), respectively. [Walker et al. 2017]By modeling the systems of the sources and stars, the authors show that the size, location, orientation, and numbers of plasma concentrations necessary to explain observations are all consistent with an environment similar to that of the Helix Nebula. Walker and collaborators find that the total mass in the molecular clumps surrounding the two stars would need to be comparable to the mass of the stars themselves.If this picture is correct, and if all stars are indeed surrounded by molecular clumps like these, then a substantial fraction of the mass of ourgalaxy could be contained in these clumps. Besides explaining distant quasar scintillation, this idea would therefore have a significant impact on our overall understanding of how mass in galaxies is distributed. More observations of twinkling quasars are the next step toward confirming this picture.CitationMark A. Walker et al 2017 ApJ 843 15. doi:10.3847/1538-4357/aa705c

  12. The Cosmic Dance of Distant Galaxies

    Science.gov (United States)

    2006-03-01

    GIRAFFE at VLT reveals the turbulent life of distant galaxies Studying several tens of distant galaxies, an international team of astronomers found that galaxies had the same amount of dark matter relative to stars 6 billion years ago as they have now. If confirmed, this suggests a much closer interplay between dark and normal matter than previously believed. The scientists also found that as many as 4 out of 10 galaxies are out of balance. These results shed a new light on how galaxies form and evolve since the Universe was only half its current age. ESO PR Photo 10a/06 ESO PR Photo 10a/06 Collision Between Galaxies (Artist's Impression) "This may imply that collisions and merging are important in the formation and evolution of galaxies", said François Hammer, Paris Observatory, France, and one of the leaders of the team [1]. The scientists were interested in finding out how galaxies that are far away - thus seen as they were when the Universe was younger - evolved into the ones nearby. In particular, they wanted to study the importance of dark matter in galaxies. "Dark matter, which composes about 25% of the Universe, is a simple word to describe something we really don't understand," said Hector Flores, co-leader. "From looking at how galaxies rotate, we know that dark matter must be present, as otherwise these gigantic structures would just dissolve." In nearby galaxies, and in our own Milky Way for that matter, astronomers have found that there exists a relation between the amount of dark matter and ordinary stars: for every kilogram of material within a star there is roughly 30 kilograms of dark matter. But does this relation between dark and ordinary matter still hold in the Universe's past? ESO PR Photo 10b/06 ESO PR Photo 10b/06 Mapping Distant Galaxies (FLAMES-GIRAFFE/VLT) This required measuring the velocity in different parts of distant galaxies, a rather tricky experiment: previous measurements were indeed unable to probe these galaxies in sufficient

  13. Distant Site Effects of Ingested Prebiotics

    Directory of Open Access Journals (Sweden)

    Stephanie Collins

    2016-08-01

    Full Text Available The gut microbiome is being more widely recognized for its association with positive health outcomes, including those distant to the gastrointestinal system. This has given the ability to maintain and restore microbial homeostasis a new significance. Prebiotic compounds are appealing for this purpose as they are generally food-grade substances only degraded by microbes, such as bifidobacteria and lactobacilli, from which beneficial short-chain fatty acids are produced. Saccharides such as inulin and other fructo-oligosaccharides, galactooligosaccharides, and polydextrose have been widely used to improve gastrointestinal outcomes, but they appear to also influence distant sites. This review examined the effects of prebiotics on bone strength, neural and cognitive processes, immune functioning, skin, and serum lipid profile. The mode of action is in part affected by intestinal permeability and by fermentation products reaching target cells. As the types of prebiotics available diversify, so too will our understanding of the range of microbes able to degrade them, and the extent to which body sites can be impacted by their consumption.

  14. ALMA Examines a Distant Quasar Host

    Science.gov (United States)

    Kohler, Susanna

    2017-04-01

    The dust continuum (top) and the [CII] emission (bottom) maps for the region around J1120+0641. [Adapted from Venemans et al. 2017]A team of scientists has used the Atacama Large Millimeter/submillimeter Array (ALMA) to explore the host galaxy of the most distant quasar known. Their observations may help us to build a picture of how the first supermassive black holes in the universe formed and evolved.Faraway Monsters and Their GalaxiesWe know that quasars the incredibly luminous and active centers of some distant galaxies are powered by accreting, supermassive black holes. These monstrous powerhouses have been detected out to redshifts of z 7, when the universe was younger than a billion years old.Though weve observed over a hundred quasars at high redshift, we still dont understand how these early supermassive black holes formed, or whether the black holes and the galaxies that host them co-evolved. In order to answer questions like these, however, we first need to gather information about the properties and behavior of various supermassive black holes and their host galaxies.A team of scientists led by Bram Venemans (Max-Planck Institute for Astronomy, Germany) recently used the unprecedented sensitivity and angular resolution of ALMA as well as the Very Large Array and the IRAM Plateau de Bure Interferometer to examine the most distant quasar currently known, J1120+0641, located at a redshift of z = 7.1.A High-Resolution LookThe teams observations of the dust and gas emission from the quasars host galaxy revealed a number of intriguing things:The red and blue sides of the [CII] emission line are shown here as contours, demonstrating that theres no ordered rotational motion of the gas on kpc scales. [Adapted from Venemans et al. 2017]The majority of the galaxys emission is very compact. Around 80% of the observed flux came from a region of only 11.5 kpc in diameter.Despite the fact that the 2.4-billion-solar-mass black hole at the galaxys center is accreting at

  15. Transfer and capture into distant retrograde orbits

    Science.gov (United States)

    Scott, Christopher J.

    This dissertation utilizes theory and techniques derived from the fields of dynamical systems theory, astrodyanamics, celestial mechanics, and fluid mechanics to analyze the phenomenon of satellite capture and interrelated spacecraft transfers in restricted three-body systems. The results extend current knowledge and understanding of capture dynamics in the context of astrodynamics and celestial mechanics. Manifold theory, fast Lyapunov indicator maps, and the classification of space structure facilitate an analysis of the transport of objects from the chaotic reaches of the solar system to the distant retrograde region in the sun-Jupiter system. Apart from past studies this dissertation considers the role of the complex lobe structure encompassing stable regions in the circular restricted three-body problem. These structures are shown to be responsible for the phenomenon of sticky orbits and the transport of objects among stable regions. Since permanent capture can only be achieved through a change in energy, fast Lyapunov indicator maps and other methods which reveal the structure of the conservative system are used to discern capture regions and identify the underpinnings of the dynamics. Fast Lyapunov indicator maps provide an accurate classification of orbits of permanent capture and escape, yet monopolize computational resources. In anticipation of a fully three-dimensional analysis in the dissipative system a new mapping parameter is introduced based on energy degradation and averaged velocity. Although the study specifically addresses the sun-Jupiter system, the qualitative results and devised techniques can be applied throughout the solar system and to capture about extrasolar planets. Extending the analysis beyond the exterior of the stable distant retrograde region fosters the construction of transfer orbits from low-Earth orbit to a stable periodic orbit at the center of the stable distant retrograde region. Key to this analysis is the predictability of

  16. When curiosity kills no cat - but mediates the relation between distant future thoughts and global processing across sensory modalities

    NARCIS (Netherlands)

    Förster, J.; Becker, D.

    2012-01-01

    Four studies examined the effect of primed temporal distance on global versus local perception, using auditory, haptic, gustatory, and olfactory stimuli. The studies show that thinking of the more distant (versus proximal) future facilitated Gestalt perception and impaired perception of details

  17. Arabic medical entity tagging using distant learning

    Directory of Open Access Journals (Sweden)

    Viviana Cotik

    2017-04-01

    Full Text Available A semantic tagger aiming to detect relevant entities in Arabic medical documents and tagging them with their appropriate semantic class is presented. The system takes profit of a Multilingual Framework covering four languages (Arabic, English, French, and Spanish, in a way that resources available for each language can be used to improve the results of the others, this is specially important for less resourced languages as Arabic. The approach has been evaluated against Wikipedia pages of the four languages belonging to the medical domain. The core of the system is the definition of a base tagset consisting of the three most represented classes in SNOMED-CT taxonomy and the learning of a binary classifier for each semantic category in the tagset and each language, using a distant learning approach over three widely used knowledge resources, namely Wikipedia, Dbpedia, and SNOMED-CT.

  18. Black-hole masses of distant quasars

    DEFF Research Database (Denmark)

    Vestergaard, Marianne

    2011-01-01

    A brief overview of the methods commonly used to determine or estimate the black hole mass in quiescent or active galaxies is presented and it is argued that the use of mass-scaling relations is both a reliable and the preferred method to apply to large samples of distant quasars. The method uses...... that the black hole masses are very large, of order 1 to 10 billion solar masses, even at the highest redshifts of 4 to 6. The black holes must build up their mass very fast in the early universe. Yet they do not grow much larger than that: a maximum mass of about 10 billion solar masses is also observed....... Preliminary mass functions of active black holes are presented for several quasar samples, including the Sloan Digital Sky Survey. Finally, common concerns related to the application of the mass scaling relations, especially for high redshift quasars, are briefly discussed....

  19. Snake Envenomation Causing Distant Tracheal Myonecrosis

    Directory of Open Access Journals (Sweden)

    Amina Khimani

    2013-01-01

    Full Text Available Snakebites are often believed to be poisonous. However, this is not always the case. In fact, each bite differs from snake to snake, depending on if the snake is poisonous and if there is envenomation. Venom in pit viper snakebites is often associated with local necrosis. The abundant literature selections and research articles justify local myonecrosis due to envenomation, but there is not much in the literature regarding myonecrosis at a site distant from the snakebite. We hereby present a case of a 42-year-old man who was transferred to our emergency department after a rattlesnake bit him twice. The patient, besides developing local myonecrosis at the site of the snakebite, developed necrosis of the scrotum as well as tracheal pressure myonecrosis at the site of the endotracheal tube balloon. In this review, we will attempt to discuss the myonecrosis pathophysiology and management related to the rattle snakebite.

  20. Evolutionary developmental psychology

    National Research Council Canada - National Science Library

    King, Ashley C; Bjorklund, David F

    2010-01-01

    The field of evolutionary developmental psychology can potentially broaden the horizons of mainstream evolutionary psychology by combining the principles of Darwinian evolution by natural selection...

  1. Accessibility of observable and unobservable characteristics in autobiographical memories of recent and distant past.

    Science.gov (United States)

    Karylowski, Jerzy J; Mrozinski, Blazej

    2017-02-01

    Self-reports regarding how people visualise themselves during events that occurred in the past show that for events from the distant past individuals report assuming a more external perspective than for events from the recent past [Nigro, G., & Neisser, U. (1983). Point of view in personal memories. Cognitive Psychology, 15, 467-482; Pronin, E., & Ross, L. (2006). Temporal differences in trait self-ascription. Journal of Personality & Social Psychology, 90, 197-209]. Thus it appears that, with the passage of time, representations of self embodied in memories of past events lose their position of an insider and assume a more ordinary position of self as an object seen from the perspective of an outside observer. The purpose of the present experiment was to examine this shift using a performance-based measure of accessibility. Results showed that self-judgements regarding unobservable, covert characteristics were faster for recent-compared to more distant-autobiographical events. However, self-judgements regarding observable, overt characteristics were faster for more distant events. This suggests an accessibility-based mechanism underlying the shift from internal to the relatively more external perspective in forming self-images related to the distant past.

  2. Drift and ownership toward a distant virtual body.

    Science.gov (United States)

    Pomés, Ausiàs; Slater, Mel

    2013-01-01

    In body ownership illusions participants feel that a mannequin or virtual body (VB) is their own. Earlier results suggest that body ownership over a body seen from behind in extra personal space is possible when the surrogate body is visually stroked and tapped on its back, while spatially and temporal synchronous tactile stimulation is applied to the participant's back. This result has been disputed with the claim that the results can be explained by self-recognition rather than somatic body ownership. We carried out an experiment with 30 participants in a between-groups design. They all saw the back of a VB 1.2 m in front, that moved in real-time determined by upper body motion capture. All felt tactile stimulation on their back, and for 15 of them this was spatially and temporally synchronous with stimulation that they saw on the back of the VB, but asynchronous for the other 15. After 3 min a revolving fan above the VB descended and stopped at the position of the VB neck. A questionnaire assessed referral of touch to the VB, body ownership, the illusion of drifting forwards toward the VB, and the VB drifting backwards. Heart rate deceleration (HRD) and the amount of head movement during the threat period were used to assess the response to the threat from the fan. Results showed that although referral of touch was significantly greater in the synchronous condition than the asynchronous, there were no other differences between the conditions. However, a further multivariate analysis revealed that in the visuotactile synchronous condition HRD and head movement increased with the illusion of forward drift and decreased with backwards drift. Body ownership contributed positively to these drift sensations. Our conclusion is that the setup results in a contradiction-somatic feelings associated with a distant body-that the brain attempts to resolve by generating drift illusions that would make the two bodies coincide.

  3. Dam removal increases American eel abundance in distant headwater streams

    Science.gov (United States)

    Hitt, Nathaniel P.; Eyler, Sheila; Wofford, John E.B.

    2012-01-01

    American eel Anguilla rostrata abundances have undergone significant declines over the last 50 years, and migration barriers have been recognized as a contributing cause. We evaluated eel abundances in headwater streams of Shenandoah National Park, Virginia, to compare sites before and after the removal of a large downstream dam in 2004 (Embrey Dam, Rappahannock River). Eel abundances in headwater streams increased significantly after the removal of Embrey Dam. Observed eel abundances after dam removal exceeded predictions derived from autoregressive models parameterized with data prior to dam removal. Mann–Kendall analyses also revealed consistent increases in eel abundances from 2004 to 2010 but inconsistent temporal trends before dam removal. Increasing eel numbers could not be attributed to changes in local physical habitat (i.e., mean stream depth or substrate size) or regional population dynamics (i.e., abundances in Maryland streams or Virginia estuaries). Dam removal was associated with decreasing minimum eel lengths in headwater streams, suggesting that the dam previously impeded migration of many small-bodied individuals (<300 mm TL). We hypothesize that restoring connectivity to headwater streams could increase eel population growth rates by increasing female eel numbers and fecundity. This study demonstrated that dams may influence eel abundances in headwater streams up to 150 river kilometers distant, and that dam removal may provide benefits for eel management and conservation at the landscape scale.

  4. Molecular Composition Analysis of Distant Targets

    Science.gov (United States)

    Hughes, Gary B.; Lubin, Philip

    2017-01-01

    This document is the Final Report for NASA Innovative Advanced Concepts (NIAC) Phase I Grant 15-NIAC16A-0145, titled Molecular Composition Analysis of Distant Targets. The research was focused on developing a system concept for probing the molecular composition of cold solar system targets, such as Asteroids, Comets, Planets and Moons from a distant vantage, for example from a spacecraft that is orbiting the target (Hughes et al., 2015). The orbiting spacecraft is equipped with a high-power laser, which is run by electricity from photovoltaic panels. The laser is directed at a spot on the target. Materials on the surface of the target are heated by the laser beam, and begin to melt and then evaporate, forming a plume of asteroid molecules in front of the heated spot. The heated spot glows, producing blackbody illumination that is visible from the spacecraft, via a path through the evaporated plume. As the blackbody radiation from the heated spot passes through the plume of evaporated material, molecules in the plume absorb radiation in a manner that is specific to the rotational and vibrational characteristics of the specific molecules. A spectrometer aboard the spacecraft is used to observe absorption lines in the blackbody signal. The pattern of absorption can be used to estimate the molecular composition of materials in the plume, which originated on the target. Focusing on a single spot produces a borehole, and shallow subsurface profiling of the targets bulk composition is possible. At the beginning of the Phase I research, the estimated Technology Readiness Level (TRL) of the system was TRL-1. During the Phase I research, an end-to-end theoretical model of the sensor system was developed from first principles. The model includes laser energy and optical propagation, target heating, melting and evaporation of target material, plume density, thermal radiation from the heated spot, molecular cross section of likely asteroid materials, and estimation of the

  5. The Distant Type Ia Supernova Rate

    Science.gov (United States)

    Pain, R.; Fabbro, S.; Sullivan, M.; Ellis, R. S.; Aldering, G.; Astier, P.; Deustua, S. E.; Fruchter, A. S.; Goldhaber, G.; Goobar, A.; Groom, D. E.; Hardin, D.; Hook, I. M.; Howell, D. A.; Irwin, M. J.; Kim, A. G.; Kim, M. Y.; Knop, R. A.; Lee, J. C.; Perlmutter, S.; Ruiz-Lapuente, P.; Schahmaneche, K.; Schaefer, B.; Walton, N. A.

    2002-05-28

    We present a measurement of the rate of distant Type Ia supernovae derived using 4 large subsets of data from the Supernova Cosmology Project. Within this fiducial sample, which surveyed about 12 square degrees, thirty-eight supernovae were detected at redshifts 0.25--0.85. In a spatially flat cosmological model consistent with the results obtained by the Supernova Cosmology Project, we derive a rest-frame Type Ia supernova rate at a mean red shift z {approx_equal} 0.55 of 1.53 {sub -0.25}{sub -0.31}{sup 0.28}{sup 0.32} x 10{sup -4} h{sup 3} Mpc{sup -3} yr{sup -1} or 0.58{sub -0.09}{sub -0.09}{sup +0.10}{sup +0.10} h{sup 2} SNu(1 SNu = 1 supernova per century per 10{sup 10} L{sub B}sun), where the first uncertainty is statistical and the second includes systematic effects. The dependence of the rate on the assumed cosmological parameters is studied and the redshift dependence of the rate per unit comoving volume is contrasted with local estimates in the context of possible cosmic star formation histories and progenitor models.

  6. The distant type Ia supernova rate

    Energy Technology Data Exchange (ETDEWEB)

    Pain, R.; Fabbro, S.; Sullivan, M.; Ellis, R.S.; Aldering, G.; Astier, P.; Deustua, S.E.; Fruchter, A.S.; Goldhaber, G.; Goobar, A.; Groom, D.E.; Hardin, D.; Hook, I.M.; Howell, D.A.; Irwin, M.J.; Kim, A.G.; Kim, M.Y.; Knop, R.A.; Lee, J.C.; Perlmutter, S.; Ruiz-Lapuente, P.; Schahmaneche, K.; Schaefer, B.; Walton, N.A.

    2002-05-20

    We present a measurement of the rate of distant Type Ia supernovae derived using 4 large subsets of data from the Supernova Cosmology Project. Within this fiducial sample,which surveyed about 12 square degrees, thirty-eight supernovae were detected at redshifts 0.25--0.85. In a spatially flat cosmological model consistent with the results obtained by the Supernova Cosmology Project, we derive a rest-frame Type Ia supernova rate at a mean red shift z {approx_equal} 0.55 of 1.53 {sub -0.25}{sub -0.31}{sup 0.28}{sup 0.32} x 10{sup -4} h{sup 3} Mpc{sup -3} yr{sup -1} or 0.58{sub -0.09}{sub -0.09}{sup +0.10}{sup +0.10} h{sup 2} SNu(1 SNu = 1 supernova per century per 10{sup 10} L{sub B}sun), where the first uncertainty is statistical and the second includes systematic effects. The dependence of the rate on the assumed cosmological parameters is studied and the redshift dependence of the rate per unit comoving volume is contrasted with local estimates in the context of possible cosmic star formation histories and progenitor models.

  7. Distant retrograde orbits and the asteroid hazard

    Science.gov (United States)

    Perozzi, Ettore; Ceccaroni, Marta; Valsecchi, Giovanni B.; Rossi, Alessandro

    2017-08-01

    Distant Retrograde Orbits (DROs) gained a novel wave of fame in space mission design because of their numerous advantages within the framework of the US plans for bringing a large asteroid sample in the vicinity of the Earth as the next target for human exploration. DROs are stable solutions of the three-body problem that can be used whenever an object, whether of natural or artificial nature, is required to remain in the neighborhood of a celestial body without being gravitationally captured by it. As such, they represent an alternative option to Halo orbits around the collinear Lagrangian points L1 and L2. Also known under other names ( e.g., quasi-satellite orbits, cis-lunar orbits, family- f orbits) these orbital configurations found interesting applications in several mission profiles, like that of a spacecraft orbiting around the small irregularly shaped satellite of Mars Phobos or the large Jovian moon Europa. In this paper a basic explanation of the DRO dynamics is presented in order to clarify some geometrical properties that characterize them. Their accessibility is then discussed from the point of view of mission analysis under different assumptions. Finally, their relevance within the framework of the present asteroid hazard protection programs is shown, stressing the significant increase in warning time they would provide in the prediction of impactors coming from the direction of the Sun.

  8. The Far Distant Future of Alpha Centauri

    Science.gov (United States)

    Beech, M.

    A study is made of the dynamical evolution of the Centauri star system. On the basis that Centauri is composed of the twin Sun-like binary Cen AB and the ternary M-dwarf star Proxima Centauri, we consider the affects of mass loss, first from Cen A and then from Cen B upon the systems orbital characteristics and gravitational bound state. We find that as a result of system mass loss during the advanced evolutionary stages of Cen A that Proxima becomes unbound in approximately 3.5 billion years from the present. We also find that additional mass loss during the advanced evolutionary stages of Cen B results in the disassociation of Cen AB itself in about 12 billion years. The currently iconic Centauri system will ultimately disassemble, therefore, into two white dwarfs (the remnants of Cen A and Cen B) and one M-dwarf (Proxima), which will ply independent and steadily diverging paths about the galactic center. In terms of the potential exploration and even human colonization of hypothetical planets within the system, we find that Proxima Centauri offers the longest-lived and potentially most stable environment in which to settle. In contrast, Cen A will evolve away from the main sequence and enter its giant stage of evolution in about 3 billion years from now, and accordingly any (hypothetical) planets within its habitability zone will become uninhabitable. We additionally find that the habitability zone about Cen B will also be sterilized as Cen A evolves through its red giant phase.

  9. Evolutionary Information Theory

    Directory of Open Access Journals (Sweden)

    Mark Burgin

    2013-04-01

    Full Text Available Evolutionary information theory is a constructive approach that studies information in the context of evolutionary processes, which are ubiquitous in nature and society. In this paper, we develop foundations of evolutionary information theory, building several measures of evolutionary information and obtaining their properties. These measures are based on mathematical models of evolutionary computations, machines and automata. To measure evolutionary information in an invariant form, we construct and study universal evolutionary machines and automata, which form the base for evolutionary information theory. The first class of measures introduced and studied in this paper is evolutionary information size of symbolic objects relative to classes of automata or machines. In particular, it is proved that there is an invariant and optimal evolutionary information size relative to different classes of evolutionary machines. As a rule, different classes of algorithms or automata determine different information size for the same object. The more powerful classes of algorithms or automata decrease the information size of an object in comparison with the information size of an object relative to weaker4 classes of algorithms or machines. The second class of measures for evolutionary information in symbolic objects is studied by introduction of the quantity of evolutionary information about symbolic objects relative to a class of automata or machines. To give an example of applications, we briefly describe a possibility of modeling physical evolution with evolutionary machines to demonstrate applicability of evolutionary information theory to all material processes. At the end of the paper, directions for future research are suggested.

  10. Evolutionary epistemology a multiparadigm program

    CERN Document Server

    Pinxten, Rik

    1987-01-01

    This volume has its already distant origin in an inter­national conference on Evolutionary Epistemology the editors organized at the University of Ghent in November 1984. This conference aimed to follow up the endeavor started at the ERISS (Epistemologically Relevant Internalist Sociology of Science) conference organized by Don Campbell and Alex Rosen­ berg at Cazenovia Lake, New York, in June 1981, whilst in­ jecting the gist of certain current continental intellectual developments into a debate whose focus, we thought, was in danger of being narrowed too much, considering the still underdeveloped state of affairs in the field. Broadly speaking, evolutionary epistemology today con­ sists of two interrelated, yet qualitatively distinct inves­ tigative efforts. Both are drawing on Darwinian concepts, which may explain why many people have failed to discriminate them. One is the study of the evolution of the cognitive apparatus of living organisms, which is first and foremost the province of biologists and...

  11. Grounded Eyes on Distant Watery Skies

    Science.gov (United States)

    Kohler, Susanna

    2017-08-01

    , the authorshigh-resolution observations allowed them to resolve not only the stellar spectrum, but also the spectral lines fromthe hot Jupiter exoplanet itself.Obtaining a thermal spectrum of the planet permitted the team to break the usual observational degeneracy that occurs with exoplanet observations: they were able to disentangle the planet mass and its orbital inclination angle. Piskorz and collaborators found that the planet is roughly 1.7 Jupiter masses and its orbit is inclined 24 relative to our line of sight.Artists illustration of the closest three planets in the upsilon Andromedae system. The system also has a distant red-dwarf binary companion, as well as a possible fourth planet. [NASA/ESA/A. Feild (STScI)]These measurements of the orbital structure of upsilon Andromedae are critical for understanding this unusual system. With non-coplanar planets and a distant red-dwarf companion, the upsilon Andromedae system has long been suspected to lie on the precipice of instability. The new measurements of upsilon Andromeda bs orbital properties will help us to better understand how the system may have formed, evolved, and survived to today.Water FoundOne of the biggest benefits of spectroscopy of an exoplanet is the potentialto learn about its atmospheric composition. Using their NIRSPEC observations of upsilon Andromedae b and detailed atmospheric modeling, Piskorz and collaborators found that the planets opacity structure is dominated by water vapor at the wavelengths they probed.This detection of water vapor in upsilon Andromedae bs atmosphere and the constraints on the planets orbital properties demonstrate the power and potential of ground-based, high-resolution spectroscopy for characterizing exoplanets and constraining the architecture of distantsolar systems.CitationDanielle Piskorz et al 2017 AJ 154 78. doi:10.3847/1538-3881/aa7dd8

  12. Confirmation of the Most Distant Quasar

    Science.gov (United States)

    Tilvi, Vithal

    2017-08-01

    We propose for 8-orbit G141 grism observations to confirm the AGN nature of a z=7.51 galaxy, currently the most distant quasar candidate identified via NV line detection using deep G102 grism observations. The AGN evidence is further supported by a weak line detection in the ground-based MOSFIRE spectrum. Here we request grism observations to better understand the physical processes occurring in this unique galaxy, and confirm its AGN nature via additional lines: CIV, HeII and CIII. Detection of CIV alone will unambiguously confirm its AGN nature. Currently, WFC3 grism is the most efficient instrument for observing these lines as our recent work shows that the flux loss from ground-based slit-spectrographs is significant (>4x) compared with the grism measurements. Furthermore, the CIII line falls on to a bright atmospheric line making it nearly impossible to observe from the ground. Confirmation of the AGN nature of our target will be a tremendous achievement because this discovery implies that the black hole accretion was already in place within the first few million years after the big bang. This also means that at least some fraction of Lyman-break selected galaxies host AGNs, which can enhance the escape of ionizing radiation and thus contribute to the reionization of the intergalactic medium (IGM). Currently there are no observations of faint quasars, M(UV)>-23.2 mag, at z>7. Our proposed observations will push the discoveries to fainter limits, which consequently will start building an excellent base-sample for James Webb Space Telescope for studying the physical nature of sources responsible for reionizing the universe.

  13. ROSAT Discovers Unique, Distant Cluster of Galaxies

    Science.gov (United States)

    1995-06-01

    Brightest X-ray Cluster Acts as Strong Gravitational Lens Based on exciting new data obtained with the ROSAT X-ray satellite and a ground-based telescope at the ESO La Silla Observatory, a team of European astronomers [2] has just discovered a very distant cluster of galaxies with unique properties. It emits the strongest X-ray emission of any cluster ever observed by ROSAT and is accompanied by two extraordinarily luminous arcs that represent the gravitationally deflected images of even more distant objects. The combination of these unusual characteristics makes this cluster, now known as RXJ1347.5-1145, a most interesting object for further cosmological studies. DISCOVERY AND FOLLOW-UP OBSERVATIONS This strange cluster of galaxies was discovered during the All Sky Survey with the ROSAT X-ray satellite as a moderately intense X-ray source in the constellation of Virgo. It could not be identified with any already known object and additional ground-based observations were therefore soon after performed with the Max-Planck-Society/ESO 2.2-metre telescope at the La Silla observatory in Chile. These observations took place within a large--scale redshift survey of X-ray clusters of galaxies detected by the ROSAT All Sky Survey, a so-called ``ESO Key Programme'' led by astronomers from the Max-Planck-Institut fur Extraterrestrische Physik and the Osservatorio Astronomico di Brera. The main aim of this programme is to identify cluster X-ray sources, to determine the distance to the X-ray emitting clusters and to investigate their overall properties. These observations permitted to measure the redshift of the RXJ1347.5-1145 cluster as z = 0.45, i.e. it moves away from us with a velocity (about 106,000 km/sec) equal to about one-third of the velocity of light. This is an effect of the general expansion of the universe and it allows to determine the distance as about 5,000 million light-years (assuming a Hubble constant of 75 km/sec/Mpc). In other words, we see these

  14. Incredibly distant ionospheric responses to earthquake

    Science.gov (United States)

    Yusupov, Kamil; Akchurin, Adel

    2015-04-01

    Attempts to observe ionospheric responses to the earthquake has been going on for decades. In recent years, the greatest progress in the study of this question have GPS-measurements with simultaneous HF-measurements. The use of a dense network of GPS-receivers and getting with it sufficiently detailed two-dimensional maps of the total electron content (TEC) greatly clarified the nature of the ionospheric response to strong earthquakes. For ionospheric responses observation, that are remote more than 1000 km from the strong earthquakes epicentres, it is necessary to applying more sensitive methods than GPS. The most experience in the observation of the ionospheric responses to earthquakes accumulated with Doppler sounding. Using these measurements, ionospheric disturbances characteristic features (signature) have been allocated, which associated with the passage of Rayleigh waves on the surface. Particular, this Rayleigh wave signatures allocation is implemented in the Nostradamus coherent backscatter radar. The authors of this method suggest using radar techniques like a sensitive "ionospheric seismometer." The most productive allocation and studying of the vertical structure ionospheric responses could be ionosonde observations. However, their typical 15 minute sounding rate is quite sufficient for observing the regular ionosphere, but it is not enough for studying the ionospheric responses to earthquakes, because ionospheric responses is often seen only in one ionogram and it is absent in adjacent. The decisive factor in establishing the striking ionospheric response to the earthquake was the Tohoku earthquake in 2011, when there was three ionosondes distant at 870-2000 km from the epicentre. These ionosondes simultaneously showed distortion of the F1-layer traces as its multiple stratification (multiple-cusp signature - MCS), which generated by Rayleigh wave. Note that there was another fourth Japanese ionosonde. It is located a little further near boundaries

  15. LIVE DEMONSTRATION OF DISTANT EARLY WARNING SYSTEM

    Science.gov (United States)

    Hammitzsch, M.; Lendholt, M.; Wächter, J.

    2009-12-01

    The DEWS (Distant Early Warning System) [1] project, funded under the 6th Framework Programme of the European Union, has the objective to create a new generation of interoperable early warning systems based on an open sensor platform. This platform integrates OGC [2] SWE [3] compliant sensor systems for the rapid detection of earthquakes, for the monitoring of sea level, ocean floor events, and ground displacements. Based on the upstream information flow DEWS focuses on the improvement of downstream capacities of warning centres especially by improving information logistics for effective and targeted warning message aggregation for a multilingual environment. Multiple telecommunication channels will be used for the dissemination of warning messages. Wherever possible, existing standards have been integrated. The Command and Control User Interface (CCUI), a rich client application based on Eclipse RCP (Rich Client Platform) [4] and the open source GIS uDig [5], integrates various OGC services. Using WMS (Web Map Service) [6] and WFS (Web Feature Service) [7] spatial data are utilized to depict the situation picture and to integrate a simulation system via WPS (Web Processing Service) [8] to identify affected areas. Warning messages are compiled and transmitted in the OASIS [9] CAP (Common Alerting Protocol) [10] standard together with addressing information defined via EDXL-DE (Emergency Data Exchange Language - Distribution Element) [11]. Internal interfaces are realized with SOAP [12] web services. Based on results of GITEWS [13] - in particular the GITEWS Tsunami Service Bus [14] - the DEWS approach provides an implementation for tsunami early warning systems. The introductory part of the demonstration briefly explains the DEWS project, the CCUI in conjunction with operators’ workflow, the system architecture, details of information logistics and the virtual scenario of live demonstration. The live demonstration exhibits the CCUI on screen and the service

  16. TOA and AOA Statistics for Distant Circular Scattering Model

    Directory of Open Access Journals (Sweden)

    NIAN Xiaohong

    2012-09-01

    Full Text Available General scattering model is local scattering process assumed that the mobile station is located inside the scattering region, in order to study distant scattering model in suburban or hilly propagation environment, a geometrically based statistical distant circular scattering mode in macrocell environment was proposed, the closed-form expressions of the joint probability density function of the time of arrival /the angle of arrival, the marginal probability density function of the angle of arrival and the angle of departure, the marginal probability density function of the time of arrival were derived, this probability density functions provided insight into the properties of the spatial distant scattering channel model.

  17. Evolution of microgastropods (Ellobioidea, Carychiidae: integrating taxonomic, phylogenetic and evolutionary hypotheses

    Directory of Open Access Journals (Sweden)

    Weigand Alexander M

    2013-01-01

    Full Text Available Abstract Background Current biodiversity patterns are considered largely the result of past climatic and tectonic changes. In an integrative approach, we combine taxonomic and phylogenetic hypotheses to analyze temporal and geographic diversification of epigean (Carychium and subterranean (Zospeum evolutionary lineages in Carychiidae (Eupulmonata, Ellobioidea. We explicitly test three hypotheses: 1 morphospecies encompass unrecognized evolutionary lineages, 2 limited dispersal results in a close genetic relationship of geographical proximally distributed taxa and 3 major climatic and tectonic events had an impact on lineage diversification within Carychiidae. Results Initial morphospecies assignments were investigated by different molecular delimitation approaches (threshold, ABGD, GMYC and SP. Despite a conservative delimitation strategy, carychiid morphospecies comprise a great number of unrecognized evolutionary lineages. We attribute this phenomenon to historic underestimation of morphological stasis and phenotypic variability amongst lineages. The first molecular phylogenetic hypothesis for the Carychiidae (based on COI, 16S and H3 reveals Carychium and Zospeum to be reciprocally monophyletic. Geographical proximally distributed lineages are often closely related. The temporal diversification of Carychiidae is best described by a constant rate model of diversification. The evolution of Carychiidae is characterized by relatively few (long distance colonization events. We find support for an Asian origin of Carychium. Zospeum may have arrived in Europe before extant members of Carychium. Distantly related Carychium clades inhabit a wide spectrum of the available bioclimatic niche and demonstrate considerable niche overlap. Conclusions Carychiid taxonomy is in dire need of revision. An inferred wide distribution and variable phenotype suggest underestimated diversity in Zospeum. Several Carychium morphospecies are results of past taxonomic

  18. Distant Supernovae Indicate Ever-Expanding Universe

    Science.gov (United States)

    1998-12-01

    ,000 million light-years) is observed on five dates with the SUSI camera at the 3.6-m New Technology Telescope (NTT). The host galaxy is clearly visible and the supernova reaches its maximum brightness around 13 March 1997, after which it fades. In PR Photo 50b/98 of another supernova that was found at the same time, the image of the host galaxy is barely visible, most probably because it is a low surface brightness galaxy . Here, the redshift of the supernova is z = 0.40 (distance 6,000 million light-years) and the brightness peaks around 16 March 1997. Technical information: All images were obtained through an R (red) optical filtre. The image quality varies somewhat from image to image. Exposure times and seeing values: Photo 50a/98 - 11 March (300 sec; 0.73 arcsec); 13 March (600 sec; 0.79 arcsec); 16 March (600 sec; 0.72 arcsec); 29 March (1200 sec; 1.17 arcsec); 5 April (300 sec; 0.55 arcsec) and Photo 50b/98 - 11 March (300 sec; 0.50 arcsec); 13 March (600 sec; 0.81 arcsec); 16 March (600 sec; 0.90 arcsec); 29 March (1200 sec; 0.83 arcsec); 7 April (300 sec; 1.43 arcsec); 7 May (1800 sec; 1.22 arcsec). These explosions, known as Type Ia Supernovae , are distinguished by their very uniform properties, including their intrinsic brightness; this makes them ideal for the measurement of large distances, cf. ESO PR Photos 50a/98 and 50b/98 , as well as ESO Press Release 09/95. It is by means of observations of remote objects of this type that the all-important distances could be determined with sufficient accuracy. In particular, coordinated observing campaigns of Type Ia Supernovae were carried out at several of the world's major observatories. In this way it became possible to secure the crucial data that provide the basis of the new analysis. Distances to Type Ia Supernovae are larger than expected The new observations show that, compared to their nearby twins, distant supernovae appear too dim, even for a Universe which has been freely coasting (i.e. with no change of the

  19. Distant education of gifted children in the USA

    Directory of Open Access Journals (Sweden)

    Rogozhkina I. B.

    2012-06-01

    Full Text Available Distant teaching which helps to realize the main principles of contemporary education: «teaching throughout» and «lifelong teaching» becomes more and more indemand. The possibility to get education for the residents of remote districts, excess to contemporary data bases, scientific libraries and learning materials of high quality, possibility to study at a time convenient for a student and in a tempo acceptable to the one makes distant education one of the most effective form of work with gifted children. System of distant education in the USA which is one of the most sophisticated one involves a big variety of programs and courses for both ordinary and gifted students. The article analyzes the existing in the USA on-line programs for gifted children, reveals their advantages and disadvantages, discusses the distant forms of work applicable to teaching of gifted children in Russia.

  20. A Start-Up Demonstration Test Involving Distant Failures

    OpenAIRE

    Gera, Amos E.

    2013-01-01

    A new procedure for determining the acceptance or rejection of a system that undergoes a start-up demonstration set of tests is presented. It is a generalization of the recently introduced CSDF model (consecutive successes distant failures). According to the new total successes consecutive successes total failures distant failures (TSCSTFDF) procedure, a unit is accepted when either a total number of successful tests or a specified number of consecutive successes are observed before a total n...

  1. Evolutionary molecular medicine.

    Science.gov (United States)

    Nesse, Randolph M; Ganten, Detlev; Gregory, T Ryan; Omenn, Gilbert S

    2012-05-01

    Evolution has long provided a foundation for population genetics, but some major advances in evolutionary biology from the twentieth century that provide foundations for evolutionary medicine are only now being applied in molecular medicine. They include the need for both proximate and evolutionary explanations, kin selection, evolutionary models for cooperation, competition between alleles, co-evolution, and new strategies for tracing phylogenies and identifying signals of selection. Recent advances in genomics are transforming evolutionary biology in ways that create even more opportunities for progress at its interfaces with genetics, medicine, and public health. This article reviews 15 evolutionary principles and their applications in molecular medicine in hopes that readers will use them and related principles to speed the development of evolutionary molecular medicine.

  2. Protoplanetary Disc Response to Distant Tidal Encounters in Stellar Clusters

    Science.gov (United States)

    Winter, A. J.; Clarke, C. J.; Rosotti, G.; Booth, R. A.

    2018-01-01

    The majority of stars form in a clustered environment. This has an impact on the evolution of surrounding protoplanetary discs (PPDs) due to either photoevaporation or tidal truncation. Consequently, the development of planets depends on formation environment. Here we present the first thorough investigation of tidally induced angular momentum loss in PPDs in the distant regime, partly motivated by claims in the literature for the importance of distant encounters in disc evolution. We employ both theoretical predictions and dynamical/hydrodynamical simulations in 2D and 3D. Our theoretical analysis is based on that of Ostriker (1994) and leads us to conclude that in the limit that the closest approach distance xmin ≫ r, the radius of a particle ring, the fractional change in angular momentum scales as (xmin/r)-5. This asymptotic limit ensures that the cumulative effect of distant encounters is minor in terms of its influence on disc evolution. The angular momentum transfer is dominated by the m = 2 Lindblad resonance for closer encounters and by the m = 1, ω = 0 Lindblad resonance at large xmin/r. We contextualise these results by comparing expected angular momentum loss for the outer edge of a PPD due to distant and close encounters. Contrary to the suggestions of previous works we do not find that distant encounters contribute significantly to angular momentum loss in PPDs. We define an upper limit for closest approach distance where interactions are significant as a function of arbitrary host to perturber mass ratio M2/M1.

  3. Remembering the evolutionary Freud.

    Science.gov (United States)

    Young, Allan

    2006-03-01

    Throughout his career as a writer, Sigmund Freud maintained an interest in the evolutionary origins of the human mind and its neurotic and psychotic disorders. In common with many writers then and now, he believed that the evolutionary past is conserved in the mind and the brain. Today the "evolutionary Freud" is nearly forgotten. Even among Freudians, he is regarded to be a red herring, relevant only to the extent that he diverts attention from the enduring achievements of the authentic Freud. There are three ways to explain these attitudes. First, the evolutionary Freud's key work is the "Overview of the Transference Neurosis" (1915). But it was published at an inopportune moment, forty years after the author's death, during the so-called "Freud wars." Second, Freud eventually lost interest in the "Overview" and the prospect of a comprehensive evolutionary theory of psychopathology. The publication of The Ego and the Id (1923), introducing Freud's structural theory of the psyche, marked the point of no return. Finally, Freud's evolutionary theory is simply not credible. It is based on just-so stories and a thoroughly discredited evolutionary mechanism, Lamarckian use-inheritance. Explanations one and two are probably correct but also uninteresting. Explanation number three assumes that there is a fundamental difference between Freud's evolutionary narratives (not credible) and the evolutionary accounts of psychopathology that currently circulate in psychiatry and mainstream journals (credible). The assumption is mistaken but worth investigating.

  4. Back-translation for discovering distant protein homologies in the presence of frameshift mutations

    Directory of Open Access Journals (Sweden)

    Noé Laurent

    2010-01-01

    Full Text Available Abstract Background Frameshift mutations in protein-coding DNA sequences produce a drastic change in the resulting protein sequence, which prevents classic protein alignment methods from revealing the proteins' common origin. Moreover, when a large number of substitutions are additionally involved in the divergence, the homology detection becomes difficult even at the DNA level. Results We developed a novel method to infer distant homology relations of two proteins, that accounts for frameshift and point mutations that may have affected the coding sequences. We design a dynamic programming alignment algorithm over memory-efficient graph representations of the complete set of putative DNA sequences of each protein, with the goal of determining the two putative DNA sequences which have the best scoring alignment under a powerful scoring system designed to reflect the most probable evolutionary process. Our implementation is freely available at http://bioinfo.lifl.fr/path/. Conclusions Our approach allows to uncover evolutionary information that is not captured by traditional alignment methods, which is confirmed by biologically significant examples.

  5. What can distant galaxies teach us about massive stars?

    Science.gov (United States)

    Stanway, Elizabeth R.

    2017-11-01

    Observations of star-forming galaxies in the distant Universe (z > 2) are starting to confirm the importance of massive stars in shaping galaxy emission and evolution. Inevitably, these distant stellar populations are unresolved, and the limited data available must be interpreted in the context of stellar population synthesis models. With the imminent launch of JWST and the prospect of spectral observations of galaxies within a gigayear of the Big Bang, the uncertainties in modelling of massive stars are becoming increasingly important to our interpretation of the high redshift Universe. In turn, these observations of distant stellar populations will provide ever stronger tests against which to gauge the success of, and flaws in, current massive star models.

  6. DISTANT DAMAGES IN PATIENTS WITH TRAUMATIC DISEASE OF SPINAL CORD

    Directory of Open Access Journals (Sweden)

    O. I. Dulub

    2010-01-01

    Full Text Available Were marked 3 groups of patients with distant damages of spine: with develope of it at early time after vertebro-spinal cord trauma, posttraumatic distant myelopathy and posttraumatic syringogydromyelia. Develope of distant damage was in 54 patients and it was by high powerfulls traumatic action, ft connected to a hard prime damage of spinal cord (79.6% had a completely disturbance of spine cord conduction. Periods of improvement conductions changed for the worse. Confirmation of defeation and level of disturbance of spine cord conduction were done by MRI and different methods of electrophysiology. Medical support and surgical operations (decompressive and bypass operations guarantee the positive neurological results gettin almost patients.

  7. Cenozoic climate change influences mammalian evolutionary dynamics

    OpenAIRE

    Figueirido, Borja; Janis, Christine M.; Pérez-Claros, Juan A.; Renzi, Miquel de; Palmqvist, Paul

    2011-01-01

    Global climate change is having profound impacts on the natural world. However, climate influence on faunal dynamics at macroevolutionary scales remains poorly understood. In this paper we investigate the influence of climate over deep time on the diversity patterns of Cenozoic North American mammals. We use factor analysis to identify temporally correlated assemblages of taxa, or major evolutionary faunas that we can then study in relation to climatic change over the past 65 million years. T...

  8. Neural correlates of self-appraisals in the near and distant future: an event-related potential study.

    Directory of Open Access Journals (Sweden)

    Yangmei Luo

    Full Text Available To investigate perceptual and neural correlates of future self-appraisals as a function of temporal distance, event-related potentials (ERPs were recorded while participants (11 women, eight men made judgments about the applicability of trait adjectives to their near future selves (i.e., one month from now and their distant future selves (i.e., three years from now. Behavioral results indicated people used fewer positive adjectives, more negative adjectives, recalled more specific events coming to mind and felt more psychologically connected to the near future self than the distant future self. Electrophysiological results demonstrated that negative trait adjectives elicited more positive ERP deflections than did positive trait adjectives in the interval between 550 and 800 ms (late positive component within the near future self condition. However, within the same interval, there were no significant differences between negative and positive traits adjectives in the distant future self condition. The results suggest that negative emotional processing in future self-appraisals is modulated by temporal distance, consistent with predictions of construal level theory.

  9. Evolutionary Biology Today

    Indian Academy of Sciences (India)

    Home; Journals; Resonance – Journal of Science Education; Volume 7; Issue 11. Evolutionary Biology Today - The Domain of Evolutionary Biology. Amitabh Joshi. Series Article Volume 7 Issue 11 November 2002 pp 8-17. Fulltext. Click here to view fulltext PDF. Permanent link:

  10. Part E: Evolutionary Computation

    DEFF Research Database (Denmark)

    2015-01-01

    evolutionary algorithms, such as memetic algorithms, which have emerged as a very promising tool for solving many real-world problems in a multitude of areas of science and technology. Moreover, parallel evolutionary combinatorial optimization has been presented. Search operators, which are crucial in all...

  11. Evolutionary Biology Today

    Indian Academy of Sciences (India)

    Amitabh Joshi studies and teaches evolutionary ' genetics and population ecology at the Jawaharlal. Nehru Centre for Advanced. Scientific Research,. Bangalore. His current research interests are in life- history, evolution, the evolutionary genetics of biological clocks, the evolution of ecological specialization dynamics. He.

  12. Evolutionary humanoid robotics

    CERN Document Server

    Eaton, Malachy

    2015-01-01

    This book examines how two distinct strands of research on autonomous robots, evolutionary robotics and humanoid robot research, are converging. The book will be valuable for researchers and postgraduate students working in the areas of evolutionary robotics and bio-inspired computing.

  13. Evolutionary Biology Today

    Indian Academy of Sciences (India)

    Home; Journals; Resonance – Journal of Science Education; Volume 8; Issue 2. Evolutionary Biology Today - What do Evolutionary Biologists do? Amitabh Joshi. Series Article Volume 8 Issue 2 February 2003 pp 6-18. Fulltext. Click here to view fulltext PDF. Permanent link:

  14. Applying evolutionary anthropology

    OpenAIRE

    Gibson, Mhairi A; Lawson, David W

    2015-01-01

    Evolutionary anthropology provides a powerful theoretical framework for understanding how both current environments and legacies of past selection shape human behavioral diversity. This integrative and pluralistic field, combining ethnographic, demographic, and sociological methods, has provided new insights into the ultimate forces and proximate pathways that guide human adaptation and variation. Here, we present the argument that evolutionary anthropological studies of human behavior also h...

  15. Atypical modulation of distant functional connectivity by cognitive state in children with Autism Spectrum Disorders

    Directory of Open Access Journals (Sweden)

    Xiaozhen eYou

    2013-08-01

    Full Text Available We examined whether modulation of functional connectivity by cognitive state differed between pre-adolescent children with Autism Spectrum Disorders (ASD and age and IQ-matched control children. Children underwent functional magnetic resonance imaging (fMRI during two states, a resting state followed by a sustained attention task. A voxel-wise method was used to characterize functional connectivity at two levels, local (within a voxel’s 14 mm neighborhood and distant (outside of the voxel’s 14 mm neighborhood to the rest of the brain and regions exhibiting Group X State interaction were identified for both types of connectivity maps. Distant functional connectivity of regions in the left frontal lobe (dorsolateral [BA 11, 10]; supplementary motor area extending into dorsal anterior cingulate [BA 32/8]; and premotor [BA 6, 8, 9], right parietal lobe (paracentral lobule [BA 6 ]; angular gyrus [BA 39/40], and left posterior middle temporal cortex (BA 19/39 showed a Group X State interaction such that relative to the resting state, connectivity reduced (i.e., became focal in control children but increased (i.e., became diffuse in ASD children during the task state. Higher state-related increase in distant connectivity of left frontal and right angular gyrus predicted worse inattention in ASD children. Two graph theory measures (global efficiency and modularity were also sensitive to Group X State differences, with the magnitude of state-related change predicting inattention in the ASD children. Our results indicate that as ASD children transition from an unconstrained to a sustained attentional state, functional connectivity of frontal and parietal regions with the rest of the brain becomes more widespread in a manner that may be maladaptive as it was associated with attention problems in everyday life.

  16. Oxidative stress inhibits distant metastasis by human melanoma cells.

    Science.gov (United States)

    Piskounova, Elena; Agathocleous, Michalis; Murphy, Malea M; Hu, Zeping; Huddlestun, Sara E; Zhao, Zhiyu; Leitch, A Marilyn; Johnson, Timothy M; DeBerardinis, Ralph J; Morrison, Sean J

    2015-11-12

    Solid cancer cells commonly enter the blood and disseminate systemically, but are highly inefficient at forming distant metastases for poorly understood reasons. Here we studied human melanomas that differed in their metastasis histories in patients and in their capacity to metastasize in NOD-SCID-Il2rg(-/-) (NSG) mice. We show that melanomas had high frequencies of cells that formed subcutaneous tumours, but much lower percentages of cells that formed tumours after intravenous or intrasplenic transplantation, particularly among inefficiently metastasizing melanomas. Melanoma cells in the blood and visceral organs experienced oxidative stress not observed in established subcutaneous tumours. Successfully metastasizing melanomas underwent reversible metabolic changes during metastasis that increased their capacity to withstand oxidative stress, including increased dependence on NADPH-generating enzymes in the folate pathway. Antioxidants promoted distant metastasis in NSG mice. Folate pathway inhibition using low-dose methotrexate, ALDH1L2 knockdown, or MTHFD1 knockdown inhibited distant metastasis without significantly affecting the growth of subcutaneous tumours in the same mice. Oxidative stress thus limits distant metastasis by melanoma cells in vivo.

  17. Information Extraction Using Distant Supervision and Semantic Similarities

    Directory of Open Access Journals (Sweden)

    PARK, Y.

    2016-02-01

    Full Text Available Information extraction is one of the main research tasks in natural language processing and text mining that extracts useful information from unstructured sentences. Information extraction techniques include named entity recognition, relation extraction, and co-reference resolution. Among them, relation extraction refers to a task that extracts semantic relations between entities such as personal and geographic names in documents. This is an important research area, which is used in knowledge base construction and question and answering systems. This study presents relation extraction using a distant supervision learning technique among semi-supervised learning methods, which have been spotlighted in recent years to reduce human manual work and costs required for supervised learning. That is, this study proposes a method that can improve relation extraction by improving a distant supervision learning technique by applying a clustering method to create a learning corpus and semantic analysis for relation extraction that is difficult to identify using existing distant supervision. Through comparison experiments of various semantic similarity comparison methods, similarity calculation methods that are useful to relation extraction using distant supervision are searched, and a large number of accurate relation triples can be extracted using the proposed structural advantages and semantic similarity comparison.

  18. Enhancing Distant Learning through Email Communication: A Case of BOU

    Science.gov (United States)

    Rahman, K. M. Rezanur; Anwar, Sadat; Numan, Sharker Md.

    2008-01-01

    Today computer has replaced all means of traditional communication significantly. Many distant learning tools claim to be interactive, but few can offer two-way communication. Email is the most popular means of communication medium now-a-days. Therefore, it may be used as an educational tool for learning. In present socioeconomic condition of…

  19. Distant Group Responsibility in Multi-agent Systems

    NARCIS (Netherlands)

    Yazdanpanah, Vahid; Dastani, Mehdi; Baldoni, Matteo; Chopra, Amit K.; Son, Tran Cao; Hirayama, Katsutoshi; Torroni, Paolo

    2016-01-01

    In this paper, we introduce a specific form of graded group responsibility called “distant responsibility” and provides a formal analysis for this concept in multi-agent settings. This concept of responsibility is formalized in concurrent structures based on the power of agent groups in such

  20. Distinct evolutionary trajectories of primary high-grade serous ovarian cancers revealed through spatial mutational profiling.

    Science.gov (United States)

    Bashashati, Ali; Ha, Gavin; Tone, Alicia; Ding, Jiarui; Prentice, Leah M; Roth, Andrew; Rosner, Jamie; Shumansky, Karey; Kalloger, Steve; Senz, Janine; Yang, Winnie; McConechy, Melissa; Melnyk, Nataliya; Anglesio, Michael; Luk, Margaret T Y; Tse, Kane; Zeng, Thomas; Moore, Richard; Zhao, Yongjun; Marra, Marco A; Gilks, Blake; Yip, Stephen; Huntsman, David G; McAlpine, Jessica N; Shah, Sohrab P

    2013-09-01

    High-grade serous ovarian cancer (HGSC) is characterized by poor outcome, often attributed to the emergence of treatment-resistant subclones. We sought to measure the degree of genomic diversity within primary, untreated HGSCs to examine the natural state of tumour evolution prior to therapy. We performed exome sequencing, copy number analysis, targeted amplicon deep sequencing and gene expression profiling on 31 spatially and temporally separated HGSC tumour specimens (six patients), including ovarian masses, distant metastases and fallopian tube lesions. We found widespread intratumoural variation in mutation, copy number and gene expression profiles, with key driver alterations in genes present in only a subset of samples (eg PIK3CA, CTNNB1, NF1). On average, only 51.5% of mutations were present in every sample of a given case (range 10.2-91.4%), with TP53 as the only somatic mutation consistently present in all samples. Complex segmental aneuploidies, such as whole-genome doubling, were present in a subset of samples from the same individual, with divergent copy number changes segregating independently of point mutation acquisition. Reconstruction of evolutionary histories showed one patient with mixed HGSC and endometrioid histology, with common aetiologic origin in the fallopian tube and subsequent selection of different driver mutations in the histologically distinct samples. In this patient, we observed mixed cell populations in the early fallopian tube lesion, indicating that diversity arises at early stages of tumourigenesis. Our results revealed that HGSCs exhibit highly individual evolutionary trajectories and diverse genomic tapestries prior to therapy, exposing an essential biological characteristic to inform future design of personalized therapeutic solutions and investigation of drug-resistance mechanisms. © 2013 The Authors. Journal of Pathology published by John Wiley & Sons Ltd on behalf of Pathological Society of Great Britain and Ireland.

  1. Project Temporalities

    DEFF Research Database (Denmark)

    Tryggestad, Kjell; Justesen, Lise; Mouritsen, Jan

    2013-01-01

    Purpose – The purpose of this paper is to explore how animals can become stakeholders in interaction with project management technologies and what happens with project temporalities when new and surprising stakeholders become part of a project and a recognized matter of concern to be taken...... into account. Design/methodology/approach – The paper is based on a qualitative case study of a project in the building industry. The authors use actor-network theory (ANT) to analyze the emergence of animal stakeholders, stakes and temporalities. Findings – The study shows how project temporalities can...... multiply in interaction with project management technologies and how conventional linear conceptions of project time may be contested with the emergence of new non-human stakeholders and temporalities. Research limitations/implications – The study draws on ANT to show how animals can become stakeholders...

  2. Evolutionary rewiring of bacterial regulatory networks

    Directory of Open Access Journals (Sweden)

    Tiffany B. Taylor

    2015-07-01

    Full Text Available Bacteria have evolved complex regulatory networks that enable integration of multiple intracellular and extracellular signals to coordinate responses to environmental changes. However, our knowledge of how regulatory systems function and evolve is still relatively limited. There is often extensive homology between components of different networks, due to past cycles of gene duplication, divergence, and horizontal gene transfer, raising the possibility of cross-talk or redundancy. Consequently, evolutionary resilience is built into gene networks – homology between regulators can potentially allow rapid rescue of lost regulatory function across distant regions of the genome. In our recent study [Taylor, et al. Science (2015, 347(6225] we find that mutations that facilitate cross-talk between pathways can contribute to gene network evolution, but that such mutations come with severe pleiotropic costs. Arising from this work are a number of questions surrounding how this phenomenon occurs.

  3. Eco-evolutionary feedbacks, adaptive dynamics and evolutionary rescue theory.

    Science.gov (United States)

    Ferriere, Regis; Legendre, Stéphane

    2013-01-19

    Adaptive dynamics theory has been devised to account for feedbacks between ecological and evolutionary processes. Doing so opens new dimensions to and raises new challenges about evolutionary rescue. Adaptive dynamics theory predicts that successive trait substitutions driven by eco-evolutionary feedbacks can gradually erode population size or growth rate, thus potentially raising the extinction risk. Even a single trait substitution can suffice to degrade population viability drastically at once and cause 'evolutionary suicide'. In a changing environment, a population may track a viable evolutionary attractor that leads to evolutionary suicide, a phenomenon called 'evolutionary trapping'. Evolutionary trapping and suicide are commonly observed in adaptive dynamics models in which the smooth variation of traits causes catastrophic changes in ecological state. In the face of trapping and suicide, evolutionary rescue requires that the population overcome evolutionary threats generated by the adaptive process itself. Evolutionary repellors play an important role in determining how variation in environmental conditions correlates with the occurrence of evolutionary trapping and suicide, and what evolutionary pathways rescue may follow. In contrast with standard predictions of evolutionary rescue theory, low genetic variation may attenuate the threat of evolutionary suicide and small population sizes may facilitate escape from evolutionary traps.

  4. Evolutionary Mechanisms for Loneliness

    Science.gov (United States)

    Cacioppo, John T.; Cacioppo, Stephanie; Boomsma, Dorret I.

    2013-01-01

    Robert Weiss (1973) conceptualized loneliness as perceived social isolation, which he described as a gnawing, chronic disease without redeeming features. On the scale of everyday life, it is understandable how something as personally aversive as loneliness could be regarded as a blight on human existence. However, evolutionary time and evolutionary forces operate at such a different scale of organization than we experience in everyday life that personal experience is not sufficient to understand the role of loneliness in human existence. Research over the past decade suggests a very different view of loneliness than suggested by personal experience, one in which loneliness serves a variety of adaptive functions in specific habitats. We review evidence on the heritability of loneliness and outline an evolutionary theory of loneliness, with an emphasis on its potential adaptive value in an evolutionary timescale. PMID:24067110

  5. Evolutionary behavioral genetics.

    Science.gov (United States)

    Zietsch, Brendan P; de Candia, Teresa R; Keller, Matthew C

    2015-04-01

    We describe the scientific enterprise at the intersection of evolutionary psychology and behavioral genetics-a field that could be termed Evolutionary Behavioral Genetics-and how modern genetic data is revolutionizing our ability to test questions in this field. We first explain how genetically informative data and designs can be used to investigate questions about the evolution of human behavior, and describe some of the findings arising from these approaches. Second, we explain how evolutionary theory can be applied to the investigation of behavioral genetic variation. We give examples of how new data and methods provide insight into the genetic architecture of behavioral variation and what this tells us about the evolutionary processes that acted on the underlying causal genetic variants.

  6. Marine mammals: evolutionary biology

    National Research Council Canada - National Science Library

    Berta, Annalisa; Sumich, James L; Kovacs, Kit M

    2015-01-01

    The third edition of Marine Mammals: Evolutionary Biology provides a comprehensive and current assessment of the diversity, evolution, and biology of marine mammals, while highlighting the latest tools and techniques for their study...

  7. Adaptive introgression from distant Caribbean islands contributed to the diversification of a microendemic adaptive radiation of trophic specialist pupfishes.

    Directory of Open Access Journals (Sweden)

    Emilie J Richards

    2017-08-01

    Full Text Available Rapid diversification often involves complex histories of gene flow that leave variable and conflicting signatures of evolutionary relatedness across the genome. Identifying the extent and source of variation in these evolutionary relationships can provide insight into the evolutionary mechanisms involved in rapid radiations. Here we compare the discordant evolutionary relationships associated with species phenotypes across 42 whole genomes from a sympatric adaptive radiation of Cyprinodon pupfishes endemic to San Salvador Island, Bahamas and several outgroup pupfish species in order to understand the rarity of these trophic specialists within the larger radiation of Cyprinodon. 82% of the genome depicts close evolutionary relationships among the San Salvador Island species reflecting their geographic proximity, but the vast majority of variants fixed between specialist species lie in regions with discordant topologies. Top candidate adaptive introgression regions include signatures of selective sweeps and adaptive introgression of genetic variation from a single population in the northwestern Bahamas into each of the specialist species. Hard selective sweeps of genetic variation on San Salvador Island contributed 5 times more to speciation of trophic specialists than adaptive introgression of Caribbean genetic variation; however, four of the 11 introgressed regions came from a single distant island and were associated with the primary axis of oral jaw divergence within the radiation. For example, standing variation in a proto-oncogene (ski known to have effects on jaw size introgressed into one San Salvador Island specialist from an island 300 km away approximately 10 kya. The complex emerging picture of the origins of adaptive radiation on San Salvador Island indicates that multiple sources of genetic variation contributed to the adaptive phenotypes of novel trophic specialists on the island. Our findings suggest that a suite of factors

  8. A Start-Up Demonstration Test Involving Distant Failures

    Directory of Open Access Journals (Sweden)

    Amos E. Gera

    2013-01-01

    Full Text Available A new procedure for determining the acceptance or rejection of a system that undergoes a start-up demonstration set of tests is presented. It is a generalization of the recently introduced CSDF model (consecutive successes distant failures. According to the new total successes consecutive successes total failures distant failures (TSCSTFDF procedure, a unit is accepted when either a total number of successful tests or a specified number of consecutive successes are observed before a total number of failures or the occurrence of near failures which are too close to each other. The practical advantage of this new procedure is the significant reduction in the expected number of required tests together with improved second-order statistics (standard deviation.

  9. ENHANCING DISTANT LEARNING THROUGH EMAIL COMMUNICATION: A Case of BOU

    Directory of Open Access Journals (Sweden)

    K. M. Rezanur RAHMAN

    2008-04-01

    Full Text Available Today computer has replaced all means of traditional communication significantly. Many distant learning tools claim to be interactive, but few can offer two-way communication. Email is the most popular means of communication medium now-a-days. Therefore, it may be used as an educational tool for learning. In present socio-economic condition of Bangladesh, learners can afford computer, cell phone and Internet. We took this opportunity to investigate the prospective use of these tools for distant learning. The present survey has been carried out to understand the present status of Internet knowledge among the learners and their views for possible introduction of e-mail communication as supporting tool for learning. BOU’s available infrastructural facilities for providing Internet support have been investigated. Furthermore, possible solutions have been pointed out to provide e-mail facility to the learner in a cost effective way.

  10. Development of Distant Learning Laboratory and Creation of Educational Materials

    Science.gov (United States)

    Considine, Michelle

    1995-01-01

    The Office of Education's fundamental goal is to disseminate information, mostly that which relates to science and technology. In this attempt, as I have observed, the office has many programs bringing both students and teachers to NASA Langley to expose them to the facilities and to teach them some about the scientific theory and about available modern technology. As a way of expanding the audience that can be reached, as the expense of bringing people in is limiting, Marchelle Canright has proposed establishing a center dedicated to researching and producing distant learning videos. Although distant learning through telecommunications is not a new concept, as many universities, colleges, and precollege level schools offer televised courses, the research in this field has been limited. Many of the standing distant learning broadcasts are simply recordings of teachers in classrooms giving lectures to their own students; they are not aimed at the television audience. In some cases the videos are produced without a Live-lecture atmosphere, but are still only classroom lectures. In either case, however, the full range of capabilities of video production are not being fully utilized. Methods for best relaying educational material have not been explored. Possibilities for including computerized images and video clips for the purpose of showing diagrams and processes, as well as examples in fitting cases, may add considerably to the educational value of these videos. Also, through Internet and satellite links, it is possible for remote students to interact with the teachers during televised sessions. These possibilities might, also, add to the effectiveness of distant learning programs. Ms. Canright's proposed center will be dedicated to researching these possibilities and eventually spreading the results to distant learning program managers. This is the project I was involved in over the summer. As implied, the center is still at the foundation stages. Ms. Canright has

  11. Proteomics in evolutionary ecology.

    Science.gov (United States)

    Baer, B; Millar, A H

    2016-03-01

    Evolutionary ecologists are traditionally gene-focused, as genes propagate phenotypic traits across generations and mutations and recombination in the DNA generate genetic diversity required for evolutionary processes. As a consequence, the inheritance of changed DNA provides a molecular explanation for the functional changes associated with natural selection. A direct focus on proteins on the other hand, the actual molecular agents responsible for the expression of a phenotypic trait, receives far less interest from ecologists and evolutionary biologists. This is partially due to the central dogma of molecular biology that appears to define proteins as the 'dead-end of molecular information flow' as well as technical limitations in identifying and studying proteins and their diversity in the field and in many of the more exotic genera often favored in ecological studies. Here we provide an overview of a newly forming field of research that we refer to as 'Evolutionary Proteomics'. We point out that the origins of cellular function are related to the properties of polypeptide and RNA and their interactions with the environment, rather than DNA descent, and that the critical role of horizontal gene transfer in evolution is more about coopting new proteins to impact cellular processes than it is about modifying gene function. Furthermore, post-transcriptional and post-translational processes generate a remarkable diversity of mature proteins from a single gene, and the properties of these mature proteins can also influence inheritance through genetic and perhaps epigenetic mechanisms. The influence of post-transcriptional diversification on evolutionary processes could provide a novel mechanistic underpinning for elements of rapid, directed evolutionary changes and adaptations as observed for a variety of evolutionary processes. Modern state-of the art technologies based on mass spectrometry are now available to identify and quantify peptides, proteins, protein

  12. Paleoanthropology and evolutionary theory.

    Science.gov (United States)

    Tattersall, Ian

    2012-01-01

    Paleoanthropologists of the first half of the twentieth century were little concerned either with evolutionary theory or with the technicalities and broader implications of zoological nomenclature. In consequence, the paleoanthropological literature of the period consisted largely of a series of descriptions accompanied by authoritative pronouncements, together with a huge excess of hominid genera and species. Given the intellectual flimsiness of the resulting paleoanthropological framework, it is hardly surprising that in 1950 the ornithologist Ernst Mayr met little resistance when he urged the new postwar generation of paleoanthropologists to accept not only the elegant reductionism of the Evolutionary Synthesis but a vast oversimplification of hominid phylogenetic history and nomenclature. Indeed, the impact of Mayr's onslaught was so great that even when developments in evolutionary biology during the last quarter of the century brought other paleontologists to the realization that much more has been involved in evolutionary histories than the simple action of natural selection within gradually transforming lineages, paleoanthropologists proved highly reluctant to follow. Even today, paleoanthropologists are struggling to reconcile an intuitive realization that the burgeoning hominid fossil record harbors a substantial diversity of species (bringing hominid evolutionary patterns into line with that of other successful mammalian families), with the desire to cram a huge variety of morphologies into an unrealistically minimalist systematic framework. As long as this theoretical ambivalence persists, our perception of events in hominid phylogeny will continue to be distorted.

  13. Applying evolutionary anthropology.

    Science.gov (United States)

    Gibson, Mhairi A; Lawson, David W

    2015-01-01

    Evolutionary anthropology provides a powerful theoretical framework for understanding how both current environments and legacies of past selection shape human behavioral diversity. This integrative and pluralistic field, combining ethnographic, demographic, and sociological methods, has provided new insights into the ultimate forces and proximate pathways that guide human adaptation and variation. Here, we present the argument that evolutionary anthropological studies of human behavior also hold great, largely untapped, potential to guide the design, implementation, and evaluation of social and public health policy. Focusing on the key anthropological themes of reproduction, production, and distribution we highlight classic and recent research demonstrating the value of an evolutionary perspective to improving human well-being. The challenge now comes in transforming relevance into action and, for that, evolutionary behavioral anthropologists will need to forge deeper connections with other applied social scientists and policy-makers. We are hopeful that these developments are underway and that, with the current tide of enthusiasm for evidence-based approaches to policy, evolutionary anthropology is well positioned to make a strong contribution. © 2015 Wiley Periodicals, Inc.

  14. Archaeogenetics in evolutionary medicine.

    Science.gov (United States)

    Bouwman, Abigail; Rühli, Frank

    2016-09-01

    Archaeogenetics is the study of exploration of ancient DNA (aDNA) of more than 70 years old. It is an important part of the wider studies of many different areas of our past, including animal, plant and pathogen evolution and domestication events. Hereby, we address specifically the impact of research in archaeogenetics in the broader field of evolutionary medicine. Studies on ancient hominid genomes help to understand even modern health patterns. Human genetic microevolution, e.g. related to abilities of post-weaning milk consumption, and specifically genetic adaptation in disease susceptibility, e.g. towards malaria and other infectious diseases, are of the upmost importance in contributions of archeogenetics on the evolutionary understanding of human health and disease. With the increase in both the understanding of modern medical genetics and the ability to deep sequence ancient genetic information, the field of archaeogenetic evolutionary medicine is blossoming.

  15. Evolutionary synthetic biology.

    Science.gov (United States)

    Peisajovich, Sergio G

    2012-06-15

    Signaling networks process vast amounts of environmental information to generate specific cellular responses. As cellular environments change, signaling networks adapt accordingly. Here, I will discuss how the integration of synthetic biology and directed evolution approaches is shedding light on the molecular mechanisms that guide the evolution of signaling networks. In particular, I will review studies that demonstrate how different types of mutations, from the replacement of individual amino acids to the shuffling of modular domains, lead to markedly different evolutionary trajectories and consequently to diverse network rewiring. Moreover, I will argue that intrinsic evolutionary properties of signaling proteins, such as the robustness of wild type functions, the promiscuous nature of evolutionary intermediates, and the modular decoupling between binding and catalysis, play important roles in the evolution of signaling networks. Finally, I will argue that rapid advances in our ability to synthesize DNA will radically alter how we study signaling network evolution at the genome-wide level.

  16. Total Integrative Evolutionary Communication

    DEFF Research Database (Denmark)

    Nedergaard Thomsen, Ole; Brier, Søren

    2014-01-01

    In this paper we outline a cybersemiotic foundation for the trend of pragmatics-based functional linguistics, Functional Discourse Grammar. Cybersemiotics is a substantial inter- and transdisciplinary semiotic theory which integrates, on the one hand, second-order cybernetics and autopoiesis theory...... and, on the other, Peircean biosemiotics. According to Cybersemiotics, language is primarily a creative process of total integrative evolutionary communication. It comprises three evolutionary stages: (1) biological reflexive languaging (the reflexive foundation of social coordination), (2......). In this inclusive hierarchy language games subsume the other stages, and thus human evolutionary communication is primarily a symbolic-conventional practice. It is intertwined with the practice of living, that is, with different life forms, including other forms of semiotic behavior. Together they form a coherent...

  17. Teaching evolutionary biology

    Directory of Open Access Journals (Sweden)

    Rosana Tidon

    2004-01-01

    Full Text Available Evolutionary Biology integrates several disciplines of Biology in a complex and interactive manner, where a deep understanding of the subject demands knowledge in diverse areas. Since this knowledge is often inaccessible to the majority of specialized professionals, including the teachers, we present some reflections in order to stimulate discussions aimed at the improvement of the conditions of education in this area. We examine the profile of evolutionary teaching in Brazil, based on questionnaires distributed to teachers in Secondary Education in the Federal District, on data provided by the "National Institute for Educational Studies and Research", and on information collected from teachers working in various regions of this country. Issues related to biological misconceptions, curriculum and didactic material are discussed, and some proposals are presented with the objective of aiding discussions aimed at the improvement of the teaching of evolutionary biology.

  18. Comparative molecular analysis of evolutionarily distant glyceraldehyde-3-phosphate dehydrogenase from Sardina pilchardus and Octopus vulgaris.

    Science.gov (United States)

    Baibai, Tarik; Oukhattar, Laila; Mountassif, Driss; Assobhei, Omar; Serrano, Aurelio; Soukri, Abdelaziz

    2010-12-01

    The NAD(+)-dependent cytosolic glyceraldehyde-3-phosphate dehydrogenase (GAPDH, EC 1.2.1.12), which is recognized as a key to central carbon metabolism in glycolysis and gluconeogenesis and as an important allozymic polymorphic biomarker, was purified from muscles of two marine species: the skeletal muscle of Sardina pilchardus Walbaum (Teleost, Clupeida) and the incompressible arm muscle of Octopus vulgaris (Mollusca, Cephalopoda). Comparative biochemical studies have revealed that they differ in their subunit molecular masses and in pI values. Partial cDNA sequences corresponding to an internal region of the GapC genes from Sardina and Octopus were obtained by polymerase chain reaction using degenerate primers designed from highly conserved protein motifs. Alignments of the deduced amino acid sequences were used to establish the 3D structures of the active site of two enzymes as well as the phylogenetic relationships of the sardine and octopus enzymes. These two enzymes are the first two GAPDHs characterized so far from teleost fish and cephalopod, respectively. Interestingly, phylogenetic analyses indicated that the sardina GAPDH is in a cluster with the archetypical enzymes from other vertebrates, while the octopus GAPDH comes together with other molluscan sequences in a distant basal assembly closer to bacterial and fungal orthologs, thus suggesting their different evolutionary scenarios.

  19. Evolutionary Design in Art

    Science.gov (United States)

    McCormack, Jon

    Evolution is one of the most interesting and creative processes we currently understand, so it should come as no surprise that artists and designers are embracing the use of evolution in problems of artistic creativity. The material in this section illustrates the diversity of approaches being used by artists and designers in relation to evolution at the boundary of art and science. While conceptualising human creativity as an evolutionary process in itself may be controversial, what is clear is that evolutionary processes can be used to complement, even enhance human creativity, as the chapters in this section aptly demonstrate.

  20. Evolutionary Statistical Procedures

    CERN Document Server

    Baragona, Roberto; Poli, Irene

    2011-01-01

    This proposed text appears to be a good introduction to evolutionary computation for use in applied statistics research. The authors draw from a vast base of knowledge about the current literature in both the design of evolutionary algorithms and statistical techniques. Modern statistical research is on the threshold of solving increasingly complex problems in high dimensions, and the generalization of its methodology to parameters whose estimators do not follow mathematically simple distributions is underway. Many of these challenges involve optimizing functions for which analytic solutions a

  1. EVOLUTIONARY FOUNDATIONS FOR MOLECULAR MEDICINE

    Science.gov (United States)

    Nesse, Randolph M.; Ganten, Detlev; Gregory, T. Ryan; Omenn, Gilbert S.

    2015-01-01

    Evolution has long provided a foundation for population genetics, but many major advances in evolutionary biology from the 20th century are only now being applied in molecular medicine. They include the distinction between proximate and evolutionary explanations, kin selection, evolutionary models for cooperation, and new strategies for tracing phylogenies and identifying signals of selection. Recent advances in genomics are further transforming evolutionary biology and creating yet more opportunities for progress at the interface of evolution with genetics, medicine, and public health. This article reviews 15 evolutionary principles and their applications in molecular medicine in hopes that readers will use them and others to speed the development of evolutionary molecular medicine. PMID:22544168

  2. Selections from 2017: Hubble Survey Explores Distant Galaxies

    Science.gov (United States)

    Kohler, Susanna

    2017-12-01

    Editors note:In these last two weeks of 2017, well be looking at a few selections that we havent yet discussed on AAS Nova from among the most-downloaded paperspublished in AAS journals this year. The usual posting schedule will resume in January.CANDELS Multi-Wavelength Catalogs: Source Identification and Photometry in the CANDELS COSMOSSurvey FieldPublished January2017Main takeaway:A publication led byHooshang Nayyeri(UC Irvine and UC Riverside) early this year details acatalog of sources built using the Cosmic Assembly Near-infrared Deep Extragalactic Legacy Survey(CANDELS), a survey carried out by cameras on board the Hubble Space Telescope. The catalogliststhe properties of 38,000 distant galaxies visiblewithin the COSMOS field, a two-square-degree equatorial field explored in depthto answer cosmological questions.Why its interesting:Illustration showing the three-dimensional map of the dark matter distribution in theCOSMOS field. [Adapted from NASA/ESA/R. Massey(California Institute of Technology)]The depth and resolution of the CANDELS observations areuseful for addressingseveral major science goals, including the following:Studying the most distant objects in the universe at the epoch of reionization in the cosmic dawn.Understanding galaxy formation and evolution during the peak epoch of star formation in the cosmic high noon.Studying star formation from deep ultravioletobservations and studying cosmology from supernova observations.Why CANDELS is a major endeavor:CANDELS isthe largest multi-cycle treasury program ever approved on the Hubble Space Telescope using over 900 orbits between 2010 and 2013 withtwo cameras on board the spacecraftto study galaxy formation and evolution throughout cosmic time. The CANDELS images are all publicly available, and the new catalogrepresents an enormous source of information about distant objectsin our universe.CitationH. Nayyeri et al 2017 ApJS 228 7. doi:10.3847/1538-4365/228/1/7

  3. "Spooky actions at a distance": physics, psi, and distant healing.

    Science.gov (United States)

    Leder, Drew

    2005-10-01

    Over decades, consciousness research has accumulated evidence of the real and measureable existence of "spooky actions at a distance"--modes of telepathy, telekinesis, clairvoyance, and the like. More recently scientists have begun rigorous study of the effects of distant healing intention and prayer vis-a-vis nonhuman living systems and patients in clinical trials. A barrier to taking such work seriously may be the belief that it is fundamentally incompatible with the scientific world view. This article suggests that it need not be; contemporary physics has generated a series of paradigms that can be used to make sense of, interpret, and explore "psi" and distant healing. Four such models are discussed, two drawn from relativity theory and two from quantum mechanics. First is the energetic transmission model, presuming the effects of conscious intention to be mediated by an as-yet unknown energy signal. Second is the model of path facilitation. As gravity, according to general relativity, "warps" space-time, easing certain pathways of movement, so may acts of consciousness have warping and facilitating effects on the fabric of the surrounding world. Third is the model of nonlocal entanglement drawn from quantum mechanics. Perhaps people, like particles, can become entangled so they behave as one system with instantaneous and unmediated correlations across a distance. Last discussed is a model involving actualization of potentials. The act of measurement in quantum mechanics collapses a probabilistic wave function into a single outcome. Perhaps conscious healing intention can act similarly, helping to actualize one of a series of possibilities; for example, recovery from a potentially lethal tumor. Such physics-based models are not presented as explanatory but rather as suggestive. Disjunctions as well as compatibilities between the phenomena of modern physics and those of psi and distant healing are explored.

  4. Inference of distant genetic relations in humans using "1000 genomes".

    Science.gov (United States)

    Al-Khudhair, Ahmed; Qiu, Shuhao; Wyse, Meghan; Chowdhury, Shilpi; Cheng, Xi; Bekbolsynov, Dulat; Saha-Mandal, Arnab; Dutta, Rajib; Fedorova, Larisa; Fedorov, Alexei

    2015-01-07

    Nucleotide sequence differences on the whole-genome scale have been computed for 1,092 people from 14 populations publicly available by the 1000 Genomes Project. Total number of differences in genetic variants between 96,464 human pairs has been calculated. The distributions of these differences for individuals within European, Asian, or African origin were characterized by narrow unimodal peaks with mean values of 3.8, 3.5, and 5.1 million, respectively, and standard deviations of 0.1-0.03 million. The total numbers of genomic differences between pairs of all known relatives were found to be significantly lower than their respective population means and in reverse proportion to the distance of their consanguinity. By counting the total number of genomic differences it is possible to infer familial relations for people that share down to 6% of common loci identical-by-descent. Detection of familial relations can be radically improved when only very rare genetic variants are taken into account. Counting of total number of shared very rare single nucleotide polymorphisms (SNPs) from whole-genome sequences allows establishing distant familial relations for persons with eighth and ninth degrees of relationship. Using this analysis we predicted 271 distant familial pairwise relations among 1,092 individuals that have not been declared by 1000 Genomes Project. Particularly, among 89 British and 97 Chinese individuals we found three British-Chinese pairs with distant genetic relationships. Individuals from these pairs share identical-by-descent DNA fragments that represent 0.001%, 0.004%, and 0.01% of their genomes. With affordable whole-genome sequencing techniques, very rare SNPs should become important genetic markers for familial relationships and population stratification. © The Author(s) 2015. Published by Oxford University Press on behalf of the Society for Molecular Biology and Evolution.

  5. When development matters: From evolutionary psychology to evolutionary developmental psychology

    OpenAIRE

    Hernández Blasi, Carlos; Gardiner, Amy K.; Bjorklund, David F.

    2008-01-01

    This article presents evolutionary developmental psychology (EDP) as an emerging field of evolutionary psychology (EP). In describing the core tenets of both approaches and the differences between them, we emphasize the important roles that evolution and development have in understanding human behaviour. We suggest that developmental psychologists should pay more attention to evolutionary issues and, conversely, evolutionary psychologists should take development seriously. Key words: evol...

  6. Temporal naturalism

    Science.gov (United States)

    Smolin, Lee

    2015-11-01

    Two people may claim both to be naturalists, but have divergent conceptions of basic elements of the natural world which lead them to mean different things when they talk about laws of nature, or states, or the role of mathematics in physics. These disagreements do not much affect the ordinary practice of science which is about small subsystems of the universe, described or explained against a background, idealized to be fixed. But these issues become crucial when we consider including the whole universe within our system, for then there is no fixed background to reference observables to. I argue here that the key issue responsible for divergent versions of naturalism and divergent approaches to cosmology is the conception of time. One version, which I call temporal naturalism, holds that time, in the sense of the succession of present moments, is real, and that laws of nature evolve in that time. This is contrasted with timeless naturalism, which holds that laws are immutable and the present moment and its passage are illusions. I argue that temporal naturalism is empirically more adequate than the alternatives, because it offers testable explanations for puzzles its rivals cannot address, and is likely a better basis for solving major puzzles that presently face cosmology and physics. This essay also addresses the problem of qualia and experience within naturalism and argues that only temporal naturalism can make a place for qualia as intrinsic qualities of matter.

  7. Genome-scale rates of evolutionary change in bacteria.

    Science.gov (United States)

    Duchêne, Sebastian; Holt, Kathryn E; Weill, François-Xavier; Le Hello, Simon; Hawkey, Jane; Edwards, David J; Fourment, Mathieu; Holmes, Edward C

    2016-11-01

    Estimating the rates at which bacterial genomes evolve is critical to understanding major evolutionary and ecological processes such as disease emergence, long-term host-pathogen associations and short-term transmission patterns. The surge in bacterial genomic data sets provides a new opportunity to estimate these rates and reveal the factors that shape bacterial evolutionary dynamics. For many organisms estimates of evolutionary rate display an inverse association with the time-scale over which the data are sampled. However, this relationship remains unexplored in bacteria due to the difficulty in estimating genome-wide evolutionary rates, which are impacted by the extent of temporal structure in the data and the prevalence of recombination. We collected 36 whole genome sequence data sets from 16 species of bacterial pathogens to systematically estimate and compare their evolutionary rates and assess the extent of temporal structure in the absence of recombination. The majority (28/36) of data sets possessed sufficient clock-like structure to robustly estimate evolutionary rates. However, in some species reliable estimates were not possible even with 'ancient DNA' data sampled over many centuries, suggesting that they evolve very slowly or that they display extensive rate variation among lineages. The robustly estimated evolutionary rates spanned several orders of magnitude, from approximately 10-5 to 10-8 nucleotide substitutions per site year-1. This variation was negatively associated with sampling time, with this relationship best described by an exponential decay curve. To avoid potential estimation biases, such time-dependency should be considered when inferring evolutionary time-scales in bacteria.

  8. Origins of evolutionary transitions

    Indian Academy of Sciences (India)

    2014-03-15

    Mar 15, 2014 ... I define an evolutionary transition as a shift in the hierarchical level at which heritable fitness variance ... life, for example in eusocial insects, around 150 million years ago. None of these transformations was ...... affecting and heritable trait, and to introduce a mechanism which inhibits them from subsequent ...

  9. Evolutionary Stable Strategy

    Indian Academy of Sciences (India)

    IAS Admin

    After Maynard-Smith and Price [1] mathematically derived why a given behaviour or strategy was adopted by a certain proportion of the population at a given time, it was shown that a strategy which is currently stable in a population need not be stable in evolutionary time (across generations). Additionally it was sug-.

  10. Evolutionary trends in Heteroptera

    NARCIS (Netherlands)

    Cobben, R.H.

    1968-01-01

    1. This work, the first volume of a series dealing with evolutionary trends in Heteroptera, is concerned with the egg system of about 400 species. The data are presented systematically in chapters 1 and 2 with a critical review of the literature after each family.

    2. Chapter 3 evaluates facts

  11. Towards Adaptive Evolutionary Architecture

    DEFF Research Database (Denmark)

    Bak, Sebastian HOlt; Rask, Nina; Risi, Sebastian

    2016-01-01

    This paper presents first results from an interdisciplinary project, in which the fields of architecture, philosophy and artificial life are combined to explore possible futures of architecture. Through an interactive evolutionary installation, called EvoCurtain, we investigate aspects of how...

  12. Origins of evolutionary transitions.

    Science.gov (United States)

    Clarke, Ellen

    2014-04-01

    An 'evolutionary transition in individuality' or 'major transition' is a transformation in the hierarchical level at which natural selection operates on a population. In this article I give an abstract (i.e. level-neutral and substrate-neutral) articulation of the transition process in order to precisely understand how such processes can happen, especially how they can get started.

  13. Evolutionary pattern search algorithms

    Energy Technology Data Exchange (ETDEWEB)

    Hart, W.E.

    1995-09-19

    This paper defines a class of evolutionary algorithms called evolutionary pattern search algorithms (EPSAs) and analyzes their convergence properties. This class of algorithms is closely related to evolutionary programming, evolutionary strategie and real-coded genetic algorithms. EPSAs are self-adapting systems that modify the step size of the mutation operator in response to the success of previous optimization steps. The rule used to adapt the step size can be used to provide a stationary point convergence theory for EPSAs on any continuous function. This convergence theory is based on an extension of the convergence theory for generalized pattern search methods. An experimental analysis of the performance of EPSAs demonstrates that these algorithms can perform a level of global search that is comparable to that of canonical EAs. We also describe a stopping rule for EPSAs, which reliably terminated near stationary points in our experiments. This is the first stopping rule for any class of EAs that can terminate at a given distance from stationary points.

  14. Optimal Mixing Evolutionary Algorithms

    NARCIS (Netherlands)

    D. Thierens (Dirk); P.A.N. Bosman (Peter); N. Krasnogor

    2011-01-01

    htmlabstractA key search mechanism in Evolutionary Algorithms is the mixing or juxtaposing of partial solutions present in the parent solutions. In this paper we look at the efficiency of mixing in genetic algorithms (GAs) and estimation-of-distribution algorithms (EDAs). We compute the mixing

  15. Learning: An Evolutionary Analysis

    Science.gov (United States)

    Swann, Joanna

    2009-01-01

    This paper draws on the philosophy of Karl Popper to present a descriptive evolutionary epistemology that offers philosophical solutions to the following related problems: "What happens when learning takes place?" and "What happens in human learning?" It provides a detailed analysis of how learning takes place without any direct transfer of…

  16. Evolutionary mysteries in meiosis

    NARCIS (Netherlands)

    Lenormand, Thomas; Engelstädter, Jan; Johnston, Susan E.; Wijnker, Erik; Haag, Christoph R.

    2016-01-01

    Meiosis is a key event of sexual life cycles in eukaryotes. Its mechanistic details have been uncovered in several model organisms, and most of its essential features have received various and often contradictory evolutionary interpretations. In this perspective, we present an overview of these

  17. Editorial overview: Evolutionary psychology

    NARCIS (Netherlands)

    Gangestad, S.W.; Tybur, J.M.

    2016-01-01

    Functional approaches in psychology - which ask what behavior is good for - are almost as old as scientific psychology itself. Yet sophisticated, generative functional theories were not possible until developments in evolutionary biology in the mid-20th century. Arising in the last three decades,

  18. Evolutionary Developmental Psychology.

    Science.gov (United States)

    Geary, David C.; Bjorklund, David F.

    2000-01-01

    Describes evolutionary developmental psychology as the study of the genetic and ecological mechanisms that govern the development of social and cognitive competencies common to all human beings and the epigenetic (gene-environment interactions) processes that adapt these competencies to local conditions. Outlines basic assumptions and domains of…

  19. Origins of evolutionary transitions

    Indian Academy of Sciences (India)

    An `evolutionary transition in individuality' or `major transition' is a transformation in the hierarchical level at which natural selection operates on a population. In this article I give an abstract (i.e. level-neutral and substrate-neutral) articulation of the transition process in order to precisely understand how such processes can ...

  20. Evolutionary Theory under Fire.

    Science.gov (United States)

    Lewin, Roger

    1980-01-01

    Summarizes events of a conference on evolutionary biology in Chicago entitled: "Macroevolution." Reviews the theory of modern synthesis, a term used to explain Darwinism in terms of population biology and genetics. Issues presented at the conference are discussed in detail. (CS)

  1. Evolutionary developmental psychology.

    Science.gov (United States)

    King, Ashley C; Bjorklund, David F

    2010-02-01

    The field of evolutionary developmental psychology can potentially broaden the horizons of mainstream evolutionary psychology by combining the principles of Darwinian evolution by natural selection with the study of human development, focusing on the epigenetic effects that occur between humans and their environment in a way that attempts to explain how evolved psychological mechanisms become expressed in the phenotypes of adults. An evolutionary developmental perspective includes an appreciation of comparative research and we, among others, argue that contrasting the cognition of humans with that of nonhuman primates can provide a framework with which to understand how human cognitive abilities and intelligence evolved. Furthermore, we argue that several aspects of childhood (e.g., play and immature cognition) serve both as deferred adaptations as well as imparting immediate benefits. Intense selection pressure was surely exerted on childhood over human evolutionary history and, as a result, neglecting to consider the early developmental period of children when studying their later adulthood produces an incomplete picture of the evolved adaptations expressed through human behavior and cognition.

  2. Evolutionary Theories of Detection

    Energy Technology Data Exchange (ETDEWEB)

    Fitch, J P

    2005-04-29

    Current, mid-term and long range technologies for detection of pathogens and toxins are briefly described in the context of performance metrics and operational scenarios. Predictive (evolutionary) and speculative (revolutionary) assessments are given with trade-offs identified, where possible, among competing performance goals.

  3. Negotiation From a Near and Distant Time Perspective

    Science.gov (United States)

    Henderson, Marlone D.; Trope, Yaacov; Carnevale, Peter J.

    2011-01-01

    Across 3 experiments, the authors examined the effects of temporal distance on negotiation behavior. They found that greater temporal distance from negotiation decreased preference for piecemeal, single-issue consideration over integrative, multi-issue consideration (Experiment 1). They also found that greater temporal distance from an event being negotiated increased interest in conceding on the lowest priority issue and decreased interest in conceding on the highest priority issue (Experiment 2). Lastly, they found increased temporal distance from an event being negotiated produced a greater proportion of multi-issue offers, a greater likelihood of conceding on the lowest priority issue in exchange for a concession on the highest priority issue, and greater individual and joint outcomes (Experiment 3). Implications for conflict resolution and construal level theory are discussed. PMID:17014295

  4. Intraspinal meningioma with malignant transformation and distant metastasis.

    Science.gov (United States)

    Ito, Kenyu; Imagama, Shiro; Ando, Kei; Kobayashi, Kazuyoshi; Shido, Yoji; Go, Yoshida; Arima, Hideyuki; Kanbara, Shunsuke; Hirose, Takanori; Matsuyama, Yukihiro; Nishida, Yoshihiro; Ishiguro, Naoki

    2017-02-01

    Meningioma is typically considered to be a benign tumor. Malignant transformation and metastasis of meningiomas are rare. Moreover, most meningiomas are intracranial, and there are few reports on intraspinal meningiomas. This report aimed to describe the clinical features and pathological findings of a case of malignant transformation and distant metastasis of intraspinal meningioma, with a review of the literature. A 44-year-old man with a bilateral lower limb paresis was diagnosed with an intradural extramedullary tumor of the thoracic spine. Primary tumor resection was performed, and the histological findings revealed atypical meningioma. The meningioma recurred 2 years after the primary surgery, and a second resection was performed, but only partial resection was possible because of decreased motor evoked potential. At age 48, the patient's lower limb weakness returned, and a third resection was performed, and the histological finding remained atypical meningioma. At age 54, the tumor increased and stereotactic irradiation was performed. At age 60, the patient was diagnosed with metastatic tumors of the rib, lumbar vertebra, cervical spine, and sacrum. Biopsy of the rib metastatic tumor was performed, and the histological findings revealed anaplastic meningioma. This case is the first report of an intraspinal meningioma that transformed from atypical to anaplastic meningioma with distant hematogenous metastasis.

  5. Breast cancer subtypes predispose the site of distant metastases.

    Science.gov (United States)

    Soni, Abha; Ren, Zhiyong; Hameed, Omar; Chanda, Diptiman; Morgan, Charity J; Siegal, Gene P; Wei, Shi

    2015-04-01

    The distant organs to which breast cancer preferentially metastasizes are of significant clinical importance. We explored the relationship between the clinicopathologic factors and the common sites of distant metastasis in 531 consecutive patients with advanced breast cancer. Breast cancer subtype as a variable was significantly associated with all five common sites of relapse by multivariate analysis. The luminal tumors were remarkable for their significant bone-seeking phenotype and were less frequently observed in lung, brain, and pleural metastases and less likely to be associated with multiorgan relapse. The HER2 subtype demonstrated a significant liver-homing characteristic. African Americans were significantly less likely to have brain-only metastasis in patients with brain relapse. These findings further articulate that breast cancer subtypes differ not only in tumor characteristics but also in their metastatic behavior, thus raising the possibility that this knowledge could potentially be used in determining the appropriate strategy for follow-up of patients with newly diagnosed breast cancer. Copyright© by the American Society for Clinical Pathology.

  6. Video-mediated communication to support distant family connectedness.

    Science.gov (United States)

    Furukawa, Ryoko; Driessnack, Martha

    2013-02-01

    It can be difficult to maintain family connections with geographically distant members. However, advances in computer-human interaction (CHI) systems, including video-mediated communication (VMC) are emerging. While VMC does not completely substitute for physical face-to-face communication, it appears to provide a sense of virtual copresence through the addition of visual and contextual cues to verbal communication between family members. The purpose of this study was to explore current patterns of VMC use, experiences, and family functioning among self-identified VMC users separated geographically from their families. A total of 341 participants (ages 18 to above 70) completed an online survey and Family APGAR. Ninty-six percent of the participants reported that VMC was the most common communication method used and 60% used VMC at least once/week. The most common reason cited for using VMC over other methods of communication was the addition of visual cues. A significant difference between the Family APGAR scores and the number of positive comments about VMC experience was also found. This exploratory study provides insight into the acceptance of VMC and its usefulness in maintaining connections with distant family members.

  7. Skipping Posterior Dynamic Transpedicular Stabilization for Distant Segment Degenerative Disease

    Directory of Open Access Journals (Sweden)

    Bilgehan Solmaz

    2012-01-01

    Full Text Available Objective. To date, there is still no consensus on the treatment of spinal degenerative disease. Current surgical techniques to manage painful spinal disorders are imperfect. In this paper, we aimed to evaluate the prospective results of posterior transpedicular dynamic stabilization, a novel surgical approach that skips the segments that do not produce pain. This technique has been proven biomechanically and radiologically in spinal degenerative diseases. Methods. A prospective study of 18 patients averaging 54.94 years of age with distant spinal segment degenerative disease. Indications consisted of degenerative disc disease (57%, herniated nucleus pulposus (50%, spinal stenosis (14.28%, degenerative spondylolisthesis (14.28%, and foraminal stenosis (7.1%. The Oswestry Low-Back Pain Disability Questionnaire and visual analog scale (VAS for pain were recorded preoperatively and at the third and twelfth postoperative months. Results. Both the Oswestry and VAS scores showed significant improvement postoperatively (P<0.05. We observed complications in one patient who had spinal epidural hematoma. Conclusion. We recommend skipping posterior transpedicular dynamic stabilization for surgical treatment of distant segment spinal degenerative disease.

  8. Evolutionary Thinking in Environmental Economics

    NARCIS (Netherlands)

    van den Bergh, J.C.J.M.

    2007-01-01

    Evolutionary and environmental economics have a potentially close relationship. This paper reviews past and identifies potential applications of evolutionary concepts and methods to environmental economics. This covers a number of themes: resource use and ecosystem management; growth and

  9. Rhabdomyosarcoma in Children and Adolescents: Patterns and Risk Factors of Distant Metastasis.

    Science.gov (United States)

    Kim, Jeong Rye; Yoon, Hee Mang; Koh, Kyung-Nam; Jung, Ah Young; Cho, Young Ah; Lee, Jin Seong

    2017-08-01

    The objective of this study is to evaluate patterns of distant metastasis and identified factors that may increase the risk of distant metastasis in pediatric patients with rhabdomyosarcoma. This retrospective study included 69 patients (age, ≤ 20 years) who had rhabdomyosarcoma diagnosed between January 2000 and February 2016. Various imaging features, including distant metastasis, were evaluated on initial and follow-up imaging studies. Differences in the distribution of distant metastasis on the basis of the primary location were analyzed. Logistic regression analysis was performed to identify factors associated with distant metastasis. Twenty-six of the 69 patients (37.7%) had distant metastasis. Nineteen of the 26 patients had distant metastasis noted at initial presentation, and 15 of the 26 patients had new metastasis noted during follow-up. The most common site of metastasis was bone (n = 14), followed by lung (n = 12) and distant lymph nodes (n = 9). Lymph node metastasis more frequently developed in patients with primary rhabdomyosarcoma in an extremity than in patients with primary rhabdomyosarcoma that developed at other sites (p = 0.003). Of 15 patients who had metastasis during follow-up, nine (60%) did not appear to have simultaneous locoregional recurrence at the time of the discovery of distant metastasis. Older age at presentation and unfavorable sites of the primary tumor were significantly associated with distant metastasis in multivariate analysis. Distant metastasis of rhabdomyosarcomas in pediatric patients showed different patterns according to the location of the primary tumor and even occurred without local recurrence.

  10. Evolution and development: some insights from evolutionary theory

    Directory of Open Access Journals (Sweden)

    DAVID JEAN R.

    2001-01-01

    Full Text Available Developmental biology and evolutionary biology are both mature integrative disciplines which started in the 19th century and then followed parallel and independent scientific pathways. Recently, a genetical component has stepped into both disciplines (developmental genetics and evolutionary genetics pointing out the need for future convergent maturation. Indeed, the Evo-Devo approach is becoming popular among developmental biologists, based on the facts that distant groups share a common ancestry, that precise phylogenies can be worked out and that homologous genes often play similar roles during the development of very different organisms. In this essay, I try to show that the real future of Evo-Devo thinking is still broader. The evolutionary theory is a set of diverse concepts which can and should be used in any biological field. Evolutionary thinking trains to ask « why » questions and to provide logical and plausible answers. It can shed some light on a diversity of general problems such as how to distinguish homologies from analogies, the costs and benefits of multicellularity, the origin of novel structures (e.g. the head, or the evolution of sexual reproduction. In the next decade, we may expect a progressive convergence between developmental genetics and quantitative genetics.

  11. Structural organization of very small chromosomes: study on a single-celled evolutionary distant eukaryote Giardia intestinalis.

    Science.gov (United States)

    Tůmová, Pavla; Uzlíková, Magdalena; Wanner, Gerhard; Nohýnková, Eva

    2015-03-01

    During mitotic prophase, chromosomes of the pathogenic unicellular eukaryote Giardia intestinalis condense in each of the cell's two nuclei. In this study, Giardia chromosomes were investigated using light microscopy, high-resolution field emission scanning electron microscopy, and in situ hybridization. For the first time, we describe the overall morphology, condensation stages, and mitotic segregation of these chromosomes. Despite the absence of several genes involved in the cohesion and condensation pathways in the Giardia genome, we observed chromatin organization similar to those found in eukaryotes, i.e., 10-nm nucleosomal fibrils, 30-nm fibrils coiled to chromomeres or in parallel arrangements, and closely aligned sister chromatids. DNA molecules of Giardia terminate with telomeric repeats that we visualized on each of the four chromatid endings of metaphase chromosomes. Giardia chromosomes lack primary and secondary constrictions, thus preventing their classification based on the position of the centromere. The anaphase poleward segregation of sister chromatids is atypical in orientation and tends to generate lagging chromatids between daughter nuclei. In the Giardia genome database, we identified two putative members of the kleisin family thought to be responsible for condensin ring establishment. Thus far, Giardia chromosomes (300 nm to 1.5 μm) are the smallest chromosomes that were analyzed at the ultrastructural level. This study complements the existing molecular and sequencing data on Giardia chromosomes with cytological and ultrastructural information.

  12. Distant, delayed and ancient earthquake-induced landslides

    Science.gov (United States)

    Havenith, Hans-Balder; Torgoev, Almaz; Braun, Anika; Schlögel, Romy; Micu, Mihai

    2016-04-01

    On the basis of a new classification of seismically induced landslides we outline particular effects related to the delayed and distant triggering of landslides. Those cannot be predicted by state-of-the-art methods. First, for about a dozen events the 'predicted' extension of the affected area is clearly underestimated. The most problematic cases are those for which far-distant triggering of landslides had been reported, such as for the 1988 Saguenay earthquake. In Central Asia reports for such cases are known for areas marked by a thick cover of loess. One possible contributing effect could be a low-frequency resonance of the thick soils induced by distant earthquakes, especially those in the Pamir - Hindu Kush seismic region. Such deep focal and high magnitude (>>7) earthquakes are also found in Europe, first of all in the Vrancea region (Romania). For this area and others in Central Asia we computed landslide event sizes related to scenario earthquakes with M>7.5. The second particular and challenging type of triggering is the one delayed with respect to the main earthquake event: case histories have been reported for the Racha earthquake in 1991 when several larger landslides only started moving 2 or 3 days after the main shock. Similar observations were also made after other earthquake events in the U.S., such as after the 1906 San Francisco, the 1949 Tacoma, the 1959 Hebgen Lake and the 1983 Bora Peak earthquakes. Here, we will present a series of detailed examples of (partly monitored) mass movements in Central Asia that mainly developed after earthquakes, some even several weeks after the main shock: e.g. the Tektonik and Kainama landslides triggered in 1992 and 2004, respectively. We believe that the development of the massive failures is a consequence of the opening of tension cracks during the seismic shaking and their filling up with water during precipitations that followed the earthquakes. The third particular aspect analysed here is the use of large

  13. On the Existence of Evolutionary Learning Equilibriums

    Directory of Open Access Journals (Sweden)

    Masudul Alam Choudhury

    2011-12-01

    Full Text Available The usual kinds of Fixed-Point Theorems formalized on the existence of competitive equilibrium that explain much of economic theory at the core of economics can operate only on bounded and closed sets with convex mappings. But these conditions are hardly true of the real world of economic and financial complexities and perturbations. The category of learning sets explained by continuous fields of interactive, integrative and evolutionary behaviour caused by dynamic preferences at the individual and institutional and social levels cannot maintain the assumption of closed, bounded and convex sets. Thus learning sets and multi-system inter-temporal relations explained by pervasive complementarities and  participation between variables and entities, and evolution by learning, have evolutionary equilibriums. Such a study requires a new methodological approach. This paper formalizes such a methodology for evolutionary equilibriums in learning spaces. It briefly points out the universality of learning equilibriums in all mathematical structures. For a particular case though, the inter-systemic interdependence between sustainable development and ethics and economics in the specific understanding of learning domain is pointed out.

  14. Studies in evolutionary agroecology

    DEFF Research Database (Denmark)

    Wille, Wibke

    Darwinian evolution by natural selection is driven primarily by differential survival and reproduction among individuals in a population. When the evolutionary interest of an individual is in conflict with the interests of the population, the genes increasing individual fitness at the cost...... performance are not in conflict, it is unlikely that plant breeding can radically improve the results of millions of years of evolution through natural selection. However, efforts to improve crops can be very successful, when breeding is directed towards goals diverging from natural selection. The potential...... of Evolutionary Agroecology that the highest yielding individuals do not necessarily perform best as a population. The investment of resources into strategies and structures increasing individual competitive ability carries a cost. If a whole population consists of individuals investing resources to compete...

  15. Evolutionary constrained optimization

    CERN Document Server

    Deb, Kalyanmoy

    2015-01-01

    This book makes available a self-contained collection of modern research addressing the general constrained optimization problems using evolutionary algorithms. Broadly the topics covered include constraint handling for single and multi-objective optimizations; penalty function based methodology; multi-objective based methodology; new constraint handling mechanism; hybrid methodology; scaling issues in constrained optimization; design of scalable test problems; parameter adaptation in constrained optimization; handling of integer, discrete and mix variables in addition to continuous variables; application of constraint handling techniques to real-world problems; and constrained optimization in dynamic environment. There is also a separate chapter on hybrid optimization, which is gaining lots of popularity nowadays due to its capability of bridging the gap between evolutionary and classical optimization. The material in the book is useful to researchers, novice, and experts alike. The book will also be useful...

  16. Making evolutionary history count: biodiversity planning for coral reef fishes and the conservation of evolutionary processes

    Science.gov (United States)

    von der Heyden, Sophie

    2017-03-01

    Anthropogenic activities are having devastating impacts on marine systems with numerous knock-on effects on trophic functioning, species interactions and an accelerated loss of biodiversity. Establishing conservation areas can not only protect biodiversity, but also confer resilience against changes to coral reefs and their inhabitants. Planning for protection and conservation in marine systems is complex, but usually focuses on maintaining levels of biodiversity and protecting special and unique landscape features while avoiding negative impacts to socio-economic benefits. Conversely, the integration of evolutionary processes that have shaped extant species assemblages is rarely taken into account. However, it is as important to protect processes as it is to protect patterns for maintaining the evolutionary trajectories of populations and species. This review focuses on different approaches for integrating genetic analyses, such as phylogenetic diversity, phylogeography and the delineation of management units, temporal and spatial monitoring of genetic diversity and quantification of adaptive variation for protecting evolutionary resilience, into marine spatial planning, specifically for coral reef fishes. Many of these concepts are not yet readily applied to coral reef fish studies, but this synthesis highlights their potential and the importance of including historical processes into systematic biodiversity planning for conserving not only extant, but also future, biodiversity and its evolutionary potential.

  17. Anxiety: an evolutionary approach.

    OpenAIRE

    Bateson, M; Brilot, B; Nettle, D.

    2011-01-01

    Anxiety disorders are among the most common mental illnesses, with huge attendant suffering. Current treatments are not universally effective, suggesting that a deeper understanding of the causes of anxiety is needed. To understand anxiety disorders better, it is first necessary to understand the normal anxiety response. This entails considering its evolutionary function as well as the mechanisms underlying it. We argue that the function of the human anxiety response, and homologues in other ...

  18. Electron beam sounding rocket experiments for probing the distant magnetosphere

    Science.gov (United States)

    Nemzek, R. J.; Winckler, J. R.

    1991-01-01

    Electron accelerators on sounding rockets have injected 8-40-keV electrons on closed magnetospheric tail field lines near 250 km altitude in the northern auroral zone. These beams mirrored at the southern conjugate point ad returned as 'echoes' which were detected on the rocket system. The 20 percent of the beam that returned was sufficient to measure field line lengths and verify magnetospheric magnetic models, to measure fluctuating electric fields, and electron pitch angle scattering (6-10) R(E) distant, and to identify 10-100 V field-aligned potentials above the rocket. The experiment gives new insight into the motion of natural electrons in the outer Van Allen radiation belt.

  19. Topological networks for quantum communication between distant qubits

    Science.gov (United States)

    Lang, Nicolai; Büchler, Hans Peter

    2017-11-01

    Efficient communication between qubits relies on robust networks, which allow for fast and coherent transfer of quantum information. It seems natural to harvest the remarkable properties of systems characterized by topological invariants to perform this task. Here, we show that a linear network of coupled bosonic degrees of freedom, characterized by topological bands, can be employed for the efficient exchange of quantum information over large distances. Important features of our setup are that it is robust against quenched disorder, all relevant operations can be performed by global variations of parameters, and the time required for communication between distant qubits approaches linear scaling with their distance. We demonstrate that our concept can be extended to an ensemble of qubits embedded in a two-dimensional network to allow for communication between all of them.

  20. The evolutionary position of turtles revised

    Science.gov (United States)

    Zardoya, Rafael; Meyer, Axel

    2001-05-01

    Consensus on the evolutionary position of turtles within the amniote phylogeny has eluded evolutionary biologists for more than a century. This phylogenetic problem has remained unsolved partly because turtles have such a unique morphology that only few characters can be used to link them with any other group of amniotes. Among the many alternative hypotheses that have been postulated to explain the origin and phylogenetic relationships of turtles, a general agreement among paleontologists emerged in favoring the placement of turtles as the only living survivors of the anapsid reptiles (those that lack temporal fenestrae in the skull). However, recent morphological and molecular studies have radically changed our view of amniote phylogenetic relationships, and evidence is accumulating that supports the diapsid affinities of turtles. Molecular studies favor archosaurs (crocodiles and birds) as the living sister group of turtles, whereas morphological studies support lepidosaurs (tuatara, lizards, and snakes) as the closest living relatives of turtles. Accepting these hypotheses implies that turtles cannot be viewed any longer as primitive reptiles, and that they might have lost the temporal holes in the skull secondarily rather than never having had them.

  1. Asymmetric Evolutionary Games.

    Directory of Open Access Journals (Sweden)

    Alex McAvoy

    2015-08-01

    Full Text Available Evolutionary game theory is a powerful framework for studying evolution in populations of interacting individuals. A common assumption in evolutionary game theory is that interactions are symmetric, which means that the players are distinguished by only their strategies. In nature, however, the microscopic interactions between players are nearly always asymmetric due to environmental effects, differing baseline characteristics, and other possible sources of heterogeneity. To model these phenomena, we introduce into evolutionary game theory two broad classes of asymmetric interactions: ecological and genotypic. Ecological asymmetry results from variation in the environments of the players, while genotypic asymmetry is a consequence of the players having differing baseline genotypes. We develop a theory of these forms of asymmetry for games in structured populations and use the classical social dilemmas, the Prisoner's Dilemma and the Snowdrift Game, for illustrations. Interestingly, asymmetric games reveal essential differences between models of genetic evolution based on reproduction and models of cultural evolution based on imitation that are not apparent in symmetric games.

  2. Evolutionary theory and teleology.

    Science.gov (United States)

    O'Grady, R T

    1984-04-21

    The order within and among living systems can be explained rationally by postulating a process of descent with modification, effected by factors which are extrinsic or intrinsic to the organisms. Because at the time Darwin proposed his theory of evolution there was no concept of intrinsic factors which could evolve, he postulated a process of extrinsic effects--natural selection. Biological order was thus seen as an imposed, rather than an emergent, property. Evolutionary change was seen as being determined by the functional efficiency (adaptedness) of the organism in its environment, rather than by spontaneous changes in intrinsically generated organizing factors. The initial incompleteness of Darwin's explanatory model, and the axiomatization of its postulates in neo-Darwinism, has resulted in a theory of functionalism, rather than structuralism. As such, it introduces an unnecessary teleology which confounds evolutionary studies and reduces the usefulness of the theory. This problem cannot be detected from within the neo-Darwinian paradigm because the different levels of end-directed activity--teleomatic, teleonomic, and teleological--are not recognized. They are, in fact, considered to influence one another. The theory of nonequilibrium evolution avoids these problems by returning to the basic principles of biological order and developing a structuralist explanation of intrinsically generated change. Extrinsic factors may affect the resultant evolutionary pattern, but they are neither necessary nor sufficient for evolution to occur.

  3. Evolutionary mysteries in meiosis.

    Science.gov (United States)

    Lenormand, Thomas; Engelstädter, Jan; Johnston, Susan E; Wijnker, Erik; Haag, Christoph R

    2016-10-19

    Meiosis is a key event of sexual life cycles in eukaryotes. Its mechanistic details have been uncovered in several model organisms, and most of its essential features have received various and often contradictory evolutionary interpretations. In this perspective, we present an overview of these often 'weird' features. We discuss the origin of meiosis (origin of ploidy reduction and recombination, two-step meiosis), its secondary modifications (in polyploids or asexuals, inverted meiosis), its importance in punctuating life cycles (meiotic arrests, epigenetic resetting, meiotic asymmetry, meiotic fairness) and features associated with recombination (disjunction constraints, heterochiasmy, crossover interference and hotspots). We present the various evolutionary scenarios and selective pressures that have been proposed to account for these features, and we highlight that their evolutionary significance often remains largely mysterious. Resolving these mysteries will likely provide decisive steps towards understanding why sex and recombination are found in the majority of eukaryotes.This article is part of the themed issue 'Weird sex: the underappreciated diversity of sexual reproduction'. © 2016 The Author(s).

  4. Asymmetric Evolutionary Games.

    Science.gov (United States)

    McAvoy, Alex; Hauert, Christoph

    2015-08-01

    Evolutionary game theory is a powerful framework for studying evolution in populations of interacting individuals. A common assumption in evolutionary game theory is that interactions are symmetric, which means that the players are distinguished by only their strategies. In nature, however, the microscopic interactions between players are nearly always asymmetric due to environmental effects, differing baseline characteristics, and other possible sources of heterogeneity. To model these phenomena, we introduce into evolutionary game theory two broad classes of asymmetric interactions: ecological and genotypic. Ecological asymmetry results from variation in the environments of the players, while genotypic asymmetry is a consequence of the players having differing baseline genotypes. We develop a theory of these forms of asymmetry for games in structured populations and use the classical social dilemmas, the Prisoner's Dilemma and the Snowdrift Game, for illustrations. Interestingly, asymmetric games reveal essential differences between models of genetic evolution based on reproduction and models of cultural evolution based on imitation that are not apparent in symmetric games.

  5. Ixodes ricinus defensins attack distantly-related pathogens.

    Science.gov (United States)

    Tonk, Miray; Cabezas-Cruz, Alejandro; Valdés, James J; Rego, Ryan O M; Grubhoffer, Libor; Estrada-Peña, Agustín; Vilcinskas, Andreas; Kotsyfakis, Michalis; Rahnamaeian, Mohammad

    2015-12-01

    Antimicrobial peptides are ubiquitous components of eukaryotic innate immunity. Defensins are a well-known family of antimicrobial peptides, widely distributed in ticks, insects, plants and mammals, showing activity against bacteria, viruses, fungi, yeast and protozoan parasites. Ixodes ricinus is the most common tick species in Europe and is a vector of pathogens affecting human and animal health. Recently, six defensins (including two isoforms) were identified in I. ricinus. We investigated the evolution of the antimicrobial activity of I. ricinus defensins. Among the five unique defensins, only DefMT3, DefMT5 and DefMT6 showed in vitro antimicrobial activity. Each defensin was active against rather distantly-related bacteria (P < 0.05), significantly among Gram-negative species (P < 0.0001). These three defensins represent different clades within the family of tick defensins, suggesting that the last common ancestor of tick defensins may have had comparable antimicrobial activity. Differences in electrostatic potential, and amino acid substitutions in the β-hairpin and the loop bridging the α-helix and β-sheet may affect the antimicrobial activity in DefMT2 and DefMT7, which needs to be addressed. Additionally, the antimicrobial activity of the γ-core motif of selected defensins (DefMT3, DefMT6, and DefMT7) was also tested. Interestingly, compared to full length peptides, the γ-core motifs of these defensins were effective against less species of bacteria. However, the antifungal activity of the γ-core was higher than full peptides. Our results broaden the scope of research in the field of antimicrobial peptides highlighting the overlooked ability of arthropod defensins to act against distantly-related microorganisms. Copyright © 2015 Elsevier Ltd. All rights reserved.

  6. Chandra Finds Well-Established Black Holes In Distant Quasars

    Science.gov (United States)

    2002-03-01

    Pushing further back toward the first generation of objects to form in the universe, NASA's Chandra X-ray Observatory has observed the three most distant known quasars and found them to be prodigious producers of X-rays. This indicates that the supermassive black holes powering them were already in place when the Universe was only about one billion years old. "Chandra's superb sensitivity has allowed the detection of X-rays from the dawn of the modern universe, when the first massive black holes and galaxies were forming," said Niel Brandt of Penn State University, leader of one the teams involved. "These results indicate that future X-ray surveys should be able to detect the first black holes to form in the Universe." The three quasars were recently discovered at optical wavelengths by the Sloan Digital Sky Survey and are 13 billion light years from Earth, making them the most distant known quasars. The X-rays Chandra detected were emitted when the universe was only a billion years old, about 7 percent of the present age of the Universe. Since X-rays reveal conditions in the immediate vicinity of supermassive black holes, Brandt proposed that Chandra look at these objects in three snapshots of about two hours each to see if they were different from their older counterparts. The observations on January 29, 2002 were made public immediately and the four different teams quickly went to work on them. Brandt's team concluded that the quasars looked similar to ones that were at least twice as old, so the conditions around the central black hole had not changed much in that time, contrary to some theoretical expectations. A team led by Smita Mathur of Ohio State University reached a similar conclusion. "These young quasars do not appear to be any different from their older cousins, based upon our current understanding and assumptions," said Mathur. "Perhaps the most remarkable thing about them may be that they are so absolutely unremarkable." Jill Bechtold of the

  7. Comparative profiling of miRNAs and target gene identification in distant-grafting between tomato and Lycium (goji berry

    Directory of Open Access Journals (Sweden)

    A B M Khaldun

    2016-10-01

    Full Text Available Local translocation of small RNAs between cells is proved. Long distance translocation between rootstock and scion is also well documented in the homo-grafting system, but the process in distant-grafting is widely unexplored where rootstock and scion belonging to different genera. Micro RNAs are a class of small, endogenous, noncoding, gene silencing RNAs that regulate target genes of a wide range of important biological pathways in plants. In this study, tomato was grafted onto goji (Lycium chinense Mill. to reveal the insight of miRNAs regulation and expression patterns within a distant-grafting system. Goji is an important traditional Chinese medicinal plant with enriched phytochemicals. Illumina sequencing technology has identified 68 evolutionary known miRNAs of 37 miRNA families. Moreover, 168 putative novel miRNAs were also identified. Compared with control tomato, 43 (11 known and 32 novels and 163 (33 known and 130 novels miRNAs were expressed significantly different in shoot and fruit of grafted tomato, respectively. The fruiting stage was identified as the most responsive in the distant-grafting approach and 123 miRNAs were found as up-regulating in the grafted fruit which is remarkably higher compare to the grafted shoot tip (28. Potential targets of differentially expressed miRNAs were found to be involved in diverse metabolic and regulatory pathways. ADP binding activities, molybdopterin synthase complex and RNA helicase activity were found as enriched terms in GO (Gene Ontology analysis. Additionally, ‘metabolic pathways’ was revealed as the most significant pathway in KEGG (Kyoto Encyclopedia of Genes and Genomes analysis. The information of the small RNA transcriptomes that are obtained from this study might be the first miRNAs elucidation for a distant-grafting system, particularly between goji and tomato. The results from this study will provide the insights into the molecular aspects of miRNA-mediated regulation in the

  8. Transcriptome analysis of pancreatic cells across distant species highlights novel important regulator genes.

    Science.gov (United States)

    Tarifeño-Saldivia, Estefania; Lavergne, Arnaud; Bernard, Alice; Padamata, Keerthana; Bergemann, David; Voz, Marianne L; Manfroid, Isabelle; Peers, Bernard

    2017-03-21

    Defining the transcriptome and the genetic pathways of pancreatic cells is of great interest for elucidating the molecular attributes of pancreas disorders such as diabetes and cancer. As the function of the different pancreatic cell types has been maintained during vertebrate evolution, the comparison of their transcriptomes across distant vertebrate species is a means to pinpoint genes under strong evolutionary constraints due to their crucial function, which have therefore preserved their selective expression in these pancreatic cell types. In this study, RNA-sequencing was performed on pancreatic alpha, beta, and delta endocrine cells as well as the acinar and ductal exocrine cells isolated from adult zebrafish transgenic lines. Comparison of these transcriptomes identified many novel markers, including transcription factors and signaling pathway components, specific for each cell type. By performing interspecies comparisons, we identified hundreds of genes with conserved enriched expression in endocrine and exocrine cells among human, mouse, and zebrafish. This list includes many genes known as crucial for pancreatic cell formation or function, but also pinpoints many factors whose pancreatic function is still unknown. A large set of endocrine-enriched genes can already be detected at early developmental stages as revealed by the transcriptomic profiling of embryonic endocrine cells, indicating a potential role in cell differentiation. The actual involvement of conserved endocrine genes in pancreatic cell differentiation was demonstrated in zebrafish for myt1b, whose invalidation leads to a reduction of alpha cells, and for cdx4, selectively expressed in endocrine delta cells and crucial for their specification. Intriguingly, comparison of the endocrine alpha and beta cell subtypes from human, mouse, and zebrafish reveals a much lower conservation of the transcriptomic signatures for these two endocrine cell subtypes compared to the signatures of pan

  9. The evolution of planetary nebulae. VII. Modelling planetary nebulae of distant stellar systems

    Science.gov (United States)

    Schönberner, D.; Jacob, R.; Sandin, C.; Steffen, M.

    2010-11-01

    Aims: By means of hydrodynamical models we do the first investigations of how the properties of planetary nebulae are affected by their metal content and what can be learned from spatially unresolved spectrograms of planetary nebulae in distant stellar systems. Methods: We computed a new series of 1D radiation-hydrodynamics planetary nebulae model sequences with central stars of 0.595 M⊙ surrounded by initial envelope structures that differ only by their metal content. At selected phases along the evolutionary path, the hydrodynamic terms were switched off, allowing the models to relax for fixed radial structure and radiation field into their equilibrium state with respect to energy and ionisation. The analyses of the line spectra emitted from both the dynamical and static models enabled us to systematically study the influence of hydrodynamics as a function of metallicity and evolution. We also recomputed selected sequences already used in previous publications, but now with different metal abundances. These sequences were used to study the expansion properties of planetary nebulae close to the bright cut-off of the planetary nebula luminosity function. Results: Our simulations show that the metal content strongly influences the expansion of planetary nebulae: the lower the metal content, the weaker the pressure of the stellar wind bubble, but the faster the expansion of the outer shell because of the higher electron temperature. This is in variance with the predictions of the interacting-stellar-winds model (or its variants) according to which only the central-star wind is thought to be responsible for driving the expansion of a planetary nebula. Metal-poor objects around slowly evolving central stars become very dilute and are prone to depart from thermal equilibrium because then adiabatic expansion contributes to gas cooling. We find indications that photoheating and line cooling are not fully balanced in the evolved planetary nebulae of the Galactic halo

  10. Effects of the distant population density on spatial patterns of demographic dynamics

    Science.gov (United States)

    Tamura, Kohei; Masuda, Naoki

    2017-08-01

    Spatio-temporal patterns of population changes within and across countries have various implications. Different geographical, demographic and econo-societal factors seem to contribute to migratory decisions made by individual inhabitants. Focusing on internal (i.e. domestic) migration, we ask whether individuals may take into account the information on the population density in distant locations to make migratory decisions. We analyse population census data in Japan recorded with a high spatial resolution (i.e. cells of size 500×500 m) for the entirety of the country, and simulate demographic dynamics induced by the gravity model and its variants. We show that, in the census data, the population growth rate in a cell is positively correlated with the population density in nearby cells up to a distance of 20 km as well as that of the focal cell. The ordinary gravity model does not capture this empirical observation. We then show that the empirical observation is better accounted for by extensions of the gravity model such that individuals are assumed to perceive the attractiveness, approximated by the population density, of the source or destination cell of migration as the spatial average over a circle of radius ≈1 km.

  11. Evolutionary factors affecting the cross-species utility of newly developed microsatellite markers in seabirds.

    Science.gov (United States)

    Moodley, Yoshan; Masello, Juan F; Cole, Theresa L; Calderon, Luciano; Munimanda, Gopi K; Thali, Marco R; Alderman, Rachael; Cuthbert, Richard J; Marin, Manuel; Massaro, Melanie; Navarro, Joan; Phillips, Richard A; Ryan, Peter G; Suazo, Cristián G; Cherel, Yves; Weimerskirch, Henri; Quillfeldt, Petra

    2015-09-01

    Microsatellite loci are ideal for testing hypotheses relating to genetic segregation at fine spatio-temporal scales. They are also conserved among closely related species, making them potentially useful for clarifying interspecific relationships between recently diverged taxa. However, mutations at primer binding sites may lead to increased nonamplification, or disruptions that may result in decreased polymorphism in nontarget species. Furthermore, high mutation rates and constraints on allele size may also with evolutionary time, promote an increase in convergently evolved allele size classes, biasing measures of interspecific genetic differentiation. Here, we used next-generation sequencing to develop microsatellite markers from a shotgun genome sequence of the sub-Antarctic seabird, the thin-billed prion (Pachyptila belcheri), that we tested for cross-species amplification in other Pachyptila and related sub-Antarctic species. We found that heterozygosity decreased and the proportion of nonamplifying loci increased with phylogenetic distance from the target species. Surprisingly, we found that species trees estimated from interspecific FST provided better approximations of mtDNA relationships among the studied species than those estimated using DC , even though FST was more affected by null alleles. We observed a significantly nonlinear second order polynomial relationship between microsatellite and mtDNA distances. We propose that the loss of linearity with increasing mtDNA distance stems from an increasing proportion of homoplastic allele size classes that are identical in state, but not identical by descent. Therefore, despite high cross-species amplification success and high polymorphism among the closely related Pachyptila species, we caution against the use of microsatellites in phylogenetic inference among distantly related taxa. © 2015 John Wiley & Sons Ltd.

  12. Transplantes cardiopulmonar e pulmonar com doador em localidade distante Distant donor procurement for heart-lung and lung transplantation

    Directory of Open Access Journals (Sweden)

    Luis Sérgio Fragomeni

    1988-12-01

    Full Text Available Em situações específicas, os transplantes clínicos cardiopulmonar e pulmonar são, hoje, formas estabelecidas de tratamento para estágio final de doença cardiopulmonar e pulmonar. A obtenção de doadores adequados permanece o maior problema e a remoção de órgãos em localidades distantes é, hoje, uma necessidade. Embora muitos métodos de preservação pulmonar possam ser empregados, para períodos isquémicos de até 5 horas, a hipotermia e o uso de solução cardioplégica com infusão da solução de Collins modificada no tronco pulmonar tem sido método simples e eficiente para preservação do bloco coração-pulmão. Descrevemos, aqui, o método corrente que empregamos, com o qual os transplantes cardiopulmonar e pulmonar combinados foram sucedidos de excelente função cárdio-respiratória.In special situations, clinical heart-lung and lung transplantation are today established methods of therapy for end stage cardiopulmonary and pulmonary disease. Adequate donor availability remains a major problem and distant organ procurement is today a necessity. Although many methods of lung preservation can be used, for periods of up to 5 hours, hypothermic storage with cardioplegic arrest and pulmonary artery flush with modified Collins solution has proven to be a simple and reliable method of heart-lung preservation. We here describe our current method of heart-lung block protection, in which heart-lung and double lung transplantation were performed followed by excelent cardiac and pulmonary function.

  13. RNA Editing During Sexual Development Occurs in Distantly Related Filamentous Ascomycetes.

    Science.gov (United States)

    Teichert, Ines; Dahlmann, Tim A; Kück, Ulrich; Nowrousian, Minou

    2017-04-01

    RNA editing is a post-transcriptional process that modifies RNA molecules leading to transcript sequences that differ from their template DNA. A-to-I editing was found to be widely distributed in nuclear transcripts of metazoa, but was detected in fungi only recently in a study of the filamentous ascomycete Fusarium graminearum that revealed extensive A-to-I editing of mRNAs in sexual structures (fruiting bodies). Here, we searched for putative RNA editing events in RNA-seq data from Sordaria macrospora and Pyronema confluens, two distantly related filamentous ascomycetes, and in data from the Taphrinomycete Schizosaccharomyces pombe. Like F. graminearum, S. macrospora is a member of the Sordariomycetes, whereas P. confluens belongs to the early-diverging group of Pezizomycetes. We found extensive A-to-I editing in RNA-seq data from sexual mycelium from both filamentous ascomycetes, but not in vegetative structures. A-to-I editing was not detected in different stages of meiosis of S. pombe. A comparison of A-to-I editing in S. macrospora with F. graminearum and P. confluens, respectively, revealed little conservation of individual editing sites. An analysis of RNA-seq data from two sterile developmental mutants of S. macrospora showed that A-to-I editing is strongly reduced in these strains. Sequencing of cDNA fragments containing more than one editing site from P. confluens showed that at the beginning of sexual development, transcripts were incompletely edited or unedited, whereas in later stages transcripts were more extensively edited. Taken together, these data suggest that A-to-I RNA editing is an evolutionary conserved feature during fruiting body development in filamentous ascomycetes. © The Author(s) 2017. Published by Oxford University Press on behalf of the Society for Molecular Biology and Evolution.

  14. The Most Distant Object Yet Discovered in the Universe

    Science.gov (United States)

    2009-04-01

    ESO's Very Large Telescope has shown that a faint gamma-ray burst detected last Thursday is the signature of the explosion of the earliest, most distant known object in the Universe (a redshift of 8.2). The explosion apparently took place more than 13 billion years ago, only about 600 million years after the Big Bang. ESO PR Photo 17a/09 Artist's impression of a gamma-ray burst Gamma-ray bursts (GRBs) are powerful flashes of energetic gamma-rays lasting from less than a second to several minutes. They release a tremendous amount of energy in this short time making them the most powerful events in the Universe. They are thought to be mostly associated with the explosion of stars that collapse into black holes. The gamma-ray burst GRB 090423 was detected by the NASA/STFC/ASI Swift satellite during the morning (CEST) of Thursday 23 April 2009. The 10 second burst was located in the constellation of Leo (the Lion). It was soon being followed by a whole range of telescopes on the ground, including the 2.2-metre ESO/MPG telescope at La Silla and ESO's Very Large Telescope (VLT) at Paranal, both in Chile. VLT infrared observations, made 17 hours after the burst detection, allowed astronomers to establish the distance to the explosion. "We find that the light coming from the explosion has been stretched, or redshifted, considerably by the expansion of the Universe", says Nial Tanvir, the leader of the team who made the VLT observations. "With a redshift of 8.2 this is the most remote gamma-ray burst ever detected, and also the most distant object ever discovered -- by some way." Because light moves at a finite speed, looking farther into the Universe means looking back in time. The explosion occurred when the Universe was about 600 million years old, less than 5 percent of its current age. It is believed that the very first stars only formed when the Universe was between 200 and 400 million years old. "This discovery proves the importance of gamma-ray bursts in probing the

  15. Distant World in Peril Discovered from La Silla

    Science.gov (United States)

    2003-01-01

    Giant Exoplanet Orbits Giant Star Summary When, in a distant future, the Sun begins to expand and evolves into a "giant" star, the surface temperature on the Earth will rise dramatically and our home planet will eventually be incinerated by that central body. Fortunately for us, this dramatic event is several billion years away. However, that sad fate will befall another planet, just discovered in orbit about the giant star HD 47536, already within a few tens of millions of years. At a distance of nearly 400 light-years from us, it is the second-remotest planetary system discovered to date [1]. This is an interesting side-result of a major research project, now carried out by a European-Brazilian team of astronomers [2]. In the course of a three-year spectroscopic survey, they have observed about 80 giant stars in the southern sky with the advanced FEROS spectrograph on the 1.52-m telescope installed at the ESO La Silla Observatory (Chile). It is one of these stars that has just been found to host a giant planet. This is only the fourth such case known and with a diameter of about 33 million km (or 23.5 times that of our Sun), HD 47536 is by far the largest of those giant stars [1]. The distance of the planet from the star is still of the order of 300 million km (or twice the distance of the Earth from the Sun), a safe margin now, but this will not always be so. The orbital period is 712 days, i.e., somewhat less than two Earth years, and the planet's mass is 5 - 10 times that of Jupiter. The presence of exoplanets in orbit around giant stars, some of which will eventually perish into their central star (be "cannibalized"), provides a possible explanation of the anomalous abundance of certain chemical elements that is observed in the atmospheres of some stars, cf. ESO PR 10/01. This interesting discovery bodes well for coming observations of exoplanetary systems with new, more powerful instruments, like HARPS to be installed next year at the ESO 3.6-m telescope on

  16. Evolutionary genomics of Entamoeba

    Science.gov (United States)

    Weedall, Gareth D.; Hall, Neil

    2011-01-01

    Entamoeba histolytica is a human pathogen that causes amoebic dysentery and leads to significant morbidity and mortality worldwide. Understanding the genome and evolution of the parasite will help explain how, when and why it causes disease. Here we review current knowledge about the evolutionary genomics of Entamoeba: how differences between the genomes of different species may help explain different phenotypes, and how variation among E. histolytica parasites reveals patterns of population structure. The imminent expansion of the amount genome data will greatly improve our knowledge of the genus and of pathogenic species within it. PMID:21288488

  17. Comparative genomics and evolutionary biology.

    Science.gov (United States)

    Kondrashov, A S

    1999-12-01

    Data of large-scale DNA sequencing are relevant to some of the most fundamental issues in evolutionary biology: suboptimality, homology, hierarchy, ancestry, novelties, the role of natural selection, and the relative importance of directional versus stabilizing selection. Already, these data provided the best available evidence for some evolutionary phenomena, and in several cases led to refinement of old concepts. Still, the Darwinian evolutionary paradigm will successfully accommodate comparative genomics.

  18. Evolutionary contingency and SETI revisited

    Science.gov (United States)

    Cirkovic, Milan M.

    2014-07-01

    The well-known argument against the Search for ExtraTerrestrial Intelligence (SETI) due to George Gaylord Simpson is re-analyzed almost half a century later, in the light of our improved understanding of preconditions for the emergence of life and intelligence brought about by the ongoing "astrobiological revolution". Simpson's argument has been enormously influential, in particular in biological circles, and it arguably fueled the most serious opposition to SETI programmes and their funding. I argue that both proponents and opponents of Simpson's argument have occasionally mispresented its core content. Proponents often oversimplify it as just another consequence of biological contingency, thus leaving their position open to general arguments limiting the scope of contingency in evolution (such as the recent argument of Geerat Vermeij based on selection effects in the fossil record). They also tend to neglect that the argument has been presented as essentially atemporal, while referring to entities and processes that are likely to change over time; this has become even less justifiable as our astrobiological knowledge increased in recent years. Opponents have failed to see that the weaknesses in Simpson's position could be removed by restructuring of the argument; I suggest one way of such restructuring, envisioned long ago in the fictional context by Stanislaw Lem. While no firm consensus has emerged on the validity of Simpson's argument so far, I suggest that, contrary to the original motivation, today it is less an anti-SETI argument, and more an astrobiological research programme. In this research programme, SETI could be generalized into a platform for testing some of the deepest assumptions about evolutionary continuity and the relative role of contingency versus convergence on unprecedented spatial and temporal scales.

  19. Evolutionary process of deep-sea bathymodiolus mussels.

    Directory of Open Access Journals (Sweden)

    Jun-Ichi Miyazaki

    Full Text Available BACKGROUND: Since the discovery of deep-sea chemosynthesis-based communities, much work has been done to clarify their organismal and environmental aspects. However, major topics remain to be resolved, including when and how organisms invade and adapt to deep-sea environments; whether strategies for invasion and adaptation are shared by different taxa or unique to each taxon; how organisms extend their distribution and diversity; and how they become isolated to speciate in continuous waters. Deep-sea mussels are one of the dominant organisms in chemosynthesis-based communities, thus investigations of their origin and evolution contribute to resolving questions about life in those communities. METHODOLOGY/PRINCIPAL FINDING: We investigated worldwide phylogenetic relationships of deep-sea Bathymodiolus mussels and their mytilid relatives by analyzing nucleotide sequences of the mitochondrial cytochrome c oxidase subunit I (COI and NADH dehydrogenase subunit 4 (ND4 genes. Phylogenetic analysis of the concatenated sequence data showed that mussels of the subfamily Bathymodiolinae from vents and seeps were divided into four groups, and that mussels of the subfamily Modiolinae from sunken wood and whale carcasses assumed the outgroup position and shallow-water modioline mussels were positioned more distantly to the bathymodioline mussels. We provisionally hypothesized the evolutionary history of Bathymodilolus mussels by estimating evolutionary time under a relaxed molecular clock model. Diversification of bathymodioline mussels was initiated in the early Miocene, and subsequently diversification of the groups occurred in the early to middle Miocene. CONCLUSIONS/SIGNIFICANCE: The phylogenetic relationships support the "Evolutionary stepping stone hypothesis," in which mytilid ancestors exploited sunken wood and whale carcasses in their progressive adaptation to deep-sea environments. This hypothesis is also supported by the evolutionary transition of

  20. Evolutionary relationships and systematics of the alphaviruses.

    Science.gov (United States)

    Powers, A M; Brault, A C; Shirako, Y; Strauss, E G; Kang, W; Strauss, J H; Weaver, S C

    2001-11-01

    Partial E1 envelope glycoprotein gene sequences and complete structural polyprotein sequences were used to compare divergence and construct phylogenetic trees for the genus Alphavirus. Tree topologies indicated that the mosquito-borne alphaviruses could have arisen in either the Old or the New World, with at least two transoceanic introductions to account for their current distribution. The time frame for alphavirus diversification could not be estimated because maximum-likelihood analyses indicated that the nucleotide substitution rate varies considerably across sites within the genome. While most trees showed evolutionary relationships consistent with current antigenic complexes and species, several changes to the current classification are proposed. The recently identified fish alphaviruses salmon pancreas disease virus and sleeping disease virus appear to be variants or subtypes of a new alphavirus species. Southern elephant seal virus is also a new alphavirus distantly related to all of the others analyzed. Tonate virus and Venezuelan equine encephalitis virus strain 78V3531 also appear to be distinct alphavirus species based on genetic, antigenic, and ecological criteria. Trocara virus, isolated from mosquitoes in Brazil and Peru, also represents a new species and probably a new alphavirus complex.

  1. A molecular study of microbe transfer between distant environments.

    Directory of Open Access Journals (Sweden)

    Sean D Hooper

    Full Text Available BACKGROUND: Environments and their organic content are generally not static and isolated, but in a constant state of exchange and interaction with each other. Through physical or biological processes, organisms, especially microbes, may be transferred between environments whose characteristics may be quite different. The transferred microbes may not survive in their new environment, but their DNA will be deposited. In this study, we compare two environmental sequencing projects to find molecular evidence of transfer of microbes over vast geographical distances. METHODOLOGY: By studying synonymous nucleotide composition, oligomer frequency and orthology between predicted genes in metagenomics data from two environments, terrestrial and aquatic, and by correlating with phylogenetic mappings, we find that both environments are likely to contain trace amounts of microbes which have been far removed from their original habitat. We also suggest a bias in direction from soil to sea, which is consistent with the cycles of planetary wind and water. CONCLUSIONS: Our findings support the Baas-Becking hypothesis formulated in 1934, which states that due to dispersion and population sizes, microbes are likely to be found in widely disparate environments. Furthermore, the availability of genetic material from distant environments is a possible font of novel gene functions for lateral gene transfer.

  2. Earth-Mars transfers through Moon Distant Retrograde Orbits

    Science.gov (United States)

    Conte, Davide; Di Carlo, Marilena; Ho, Koki; Spencer, David B.; Vasile, Massimiliano

    2018-02-01

    This paper focuses on the trajectory design which is relevant for missions that would exploit the use of asteroid mining in stable cis-lunar orbits to facilitate deep space missions, specifically human Mars exploration. Assuming that a refueling "gas station" is present at a given lunar Distant Retrograde Orbit (DRO), ways of departing from the Earth to Mars via that DRO are analyzed. Thus, the analysis and results presented in this paper add a new cis-lunar departure orbit for Earth-Mars missions. Porkchop plots depicting the required C3 at launch, v∞ at arrival, Time of Flight (TOF), and total Δ V for various DRO departure and Mars arrival dates are created and compared with results obtained for low Δ V Low Earth Orbit (LEO) to Mars trajectories. The results show that propellant-optimal trajectories from LEO to Mars through a DRO have higher overall mission Δ V due to the additional stop at the DRO. However, they have lower Initial Mass in LEO (IMLEO) and thus lower gear ratio as well as lower TOF than direct LEO to Mars transfers. This results in a lower overall spacecraft dry mass that needs to be launched into space from Earth's surface.

  3. Radio Selection of the Most Distant Galaxy Clusters

    Science.gov (United States)

    Daddi, E.; Jin, S.; Strazzullo, V.; Sargent, M. T.; Wang, T.; Ferrari, C.; Schinnerer, E.; Smolčić, V.; Calabró, A.; Coogan, R.; Delhaize, J.; Delvecchio, I.; Elbaz, D.; Gobat, R.; Gu, Q.; Liu, D.; Novak, M.; Valentino, F.

    2017-09-01

    We show that the most distant X-ray-detected cluster known to date, Cl J1001 at {z}{spec}=2.506, hosts a strong overdensity of radio sources. Six of them are individually detected (within 10\\prime\\prime ) in deep 0\\buildrel{\\prime\\prime}\\over{.} 75 resolution VLA 3 GHz imaging, with {S}3{GHz}> 8 μ {Jy}. Of the six, an active galactic nucleus (AGN) likely affects the radio emission in two galaxies, while star formation is the dominant source powering the remaining four. We searched for cluster candidates over the full COSMOS 2 deg2 field using radio-detected 3 GHz sources and looking for peaks in {{{Σ }}}5 density maps. Cl J1001 is the strongest overdensity by far with > 10σ , with a simple {z}{phot}> 1.5 preselection. A cruder photometric rejection of zgeneration of forming galaxy clusters. In these remarkable structures, widespread star formation and AGN activity of massive galaxy cluster members, residing within the inner cluster core, will ultimately lead to radio continuum as one of the most effective means for their identification, with detection rates expected in the ballpark of 0.1-1 per square degree at z≳ 2.5. Samples of hundreds such high-redshift clusters could potentially constrain cosmological parameters and test cluster and galaxy formation models.

  4. Jupiter's distant magnetic equator region in energetic charged particle data

    Science.gov (United States)

    Paranicas, C.; Mauk, B.; Haggerty, D. K.; Clark, G. B.; Kollmann, P.; Rymer, A. M.; Connerney, J. E. P.; Bagenal, F.; Bolton, S. J.; Levin, S.

    2016-12-01

    The Juno spacecraft entered Jupiter orbit in July 2016. The first two orbits are unique, lasting 53.5 days each. Subsequent planned orbits are 14 days long. The large orbits have their apoapses close to the Jovian spin equator whereas in the later, shorter orbits, the apoapses move south away from it. The Jupiter Energetic Particle Detector Instrument (JEDI) Investigation on Juno measures ions and electrons in the tens of keV to tens of MeV energy range. JEDI is three separate instruments each with a fan of detectors. Two of the JEDI's are mounted with all their fields-of-view nearly perpendicular to the spacecraft spin axis. The third JEDI is mounted so that the FOVs usually capture directions between those toward and those away from the sun. Together with the spin rate of 2 rpm, the instruments regularly obtain a nearly complete view of the sky. In this talk, we will present the first results of a several-day campaign that will collect data near the distant magnetic equator. Juno magnetometer data is used primarily to determine charged particle pitch angles. We will also discuss the relationship between the magnetic equator and the high latitude magnetosphere in that region. JEDI data contain good diagnostic indicators that characterize magnetospheric regions; for example, times inside and outside the magnetopause are frequently apparent in energetic electron data. The data presented here will be the first of many to characterize Jupiter's complex magnetodisk.

  5. Plasmon-assisted quantum control of distant emitters

    Energy Technology Data Exchange (ETDEWEB)

    Susa, Cristian E. [Departamento de Física, Universidad del Valle, A.A. 25360, Cali (Colombia); Reina, John H., E-mail: john.reina@correounivalle.edu.co [Departamento de Física, Universidad del Valle, A.A. 25360, Cali (Colombia); Departamento de Óptica, Facultad de Física, Universidad Complutense, 28040 Madrid (Spain); Hildner, Richard [Experimentalphysik IV, Universität Bayreuth, Universitätsstrasse 30, 95447 Bayreuth (Germany)

    2014-06-27

    We show how to generate and control the correlations in a set of two distant quantum emitters coupled to a one-dimensional dissipative plasmonic waveguide. An external laser field enhances the dimer's steady-state correlations and allows an active control (switching on/off) of nonclassical correlations. The plasmon-assisted dipolar-interacting qubits exhibit persistent correlations, which in turn can be decoupled and made to evolve independently from each other. The setup enables long-distance (∼1 μm) qubit control that works for both resonant and detuned emitters. For suitable emitter initialization, we also show that the quantum correlation is always greater than the classical one. - Highlights: • Experimentally realistic setup: single emitters coupled to plasmon waveguide. • Conditional dynamics and qubit control of quantum emitters at long (>μm) distance. • Quantum mechanism: plasmon-assisted qubit coupling and driving by laser field. • Quantum discord dominates induced conditional dynamics. • Long-range quantum mechanism effective for both resonant and detuned emitters.

  6. GRBs: The Most Distant Signposts in our Universe

    Science.gov (United States)

    Kouveliotou, Chryssa

    2007-01-01

    Gamma-Ray Bursts (GRBs) are the most powerful photon sources in the Universe, rivaled only by supernovae in the magnitude of their energy release. In 1997 GRB were found to originate in host galaxies at cosmological distances, revealing the total energy of their explosions to be an astounding approx.10(exp 52) - 10(exp 53)ergs. GRB durations span over five orders of magnitude, ranging from milliseconds to thousands of seconds. The underlying sources of the energy release remain, however, unknown. Leading candidates are mergers, either of two neutron stars or of a black hole and a neutron star, and core collapses of very massive stars, called "collapsars". To date the furthest GRB galaxy has been found at a cosmological redshift of 6.29, very close to the most distant quasar (at z=6.4). Since the Swift satellite continues to observe these phenomena at a rate of approx.120 per year, and with the upcoming launch of GLAST with two burst instruments on board, we will be able to use GRBs as beacons to probe very high redshifts. Thus bursts found at 6

  7. Distant collaboration in drug discovery: The LINK3D project

    Science.gov (United States)

    Pastor, Manuel; Benedetti, Paolo; Carotti, Angelo; Carrieri, Antonio; Díaz, Carlos; Herráiz, Cristina; Höltje, Hans-Dieter; Loza, M. Isabel; Oprea, Tudor; Padín, Fernando; Pubill, Francesc; Sanz, Ferran; Stoll, Friederike; the LINK3D Consortium

    2002-11-01

    The work describes the development of novel software supporting synchronous distant collaboration between scientists involved in drug discovery and development projects. The program allows to visualize and share data as well as to interact in real time using standard intranets and Internet resources. Direct visualization of 2D and 3D molecular structures is supported and original tools for facilitating remote discussion have been integrated. The software is multiplatform (MS-Windows, SGI-IRIX, Linux), allowing for a seamless integration of heterogeneous working environments. The project aims to support collaboration both within and between academic and industrial institutions. Since confidentiality is very important in some scenarios, special attention has been paid to security aspects. The article presents the research carried out to gather the requirements of collaborative software in the field of drug discovery and development and describes the features of the first fully functional prototype obtained. Real-world testing activities carried out on this prototype in order to guarantee its adequacy in diverse environments are also described and discussed.

  8. Evolutionary status of Polaris

    Science.gov (United States)

    Fadeyev, Yu. A.

    2015-05-01

    Hydrodynamic models of short-period Cepheids were computed to determine the pulsation period as a function of evolutionary time during the first and third crossings of the instability strip. The equations of radiation hydrodynamics and turbulent convection for radial stellar pulsations were solved with the initial conditions obtained from the evolutionary models of Population I stars (X = 0.7, Z = 0.02) with masses from 5.2 to 6.5 M⊙ and the convective core overshooting parameter 0.1 ≤ αov ≤ 0.3. In Cepheids with period of 4 d the rate of pulsation period change during the first crossing of the instability strip is over 50 times larger than that during the third crossing. Polaris is shown to cross the instability strip for the first time and to be the fundamental mode pulsator. The best agreement between the predicted and observed rates of period change was obtained for the model with mass of 5.4 M⊙ and the overshooting parameter αov = 0.25. The bolometric luminosity and radius are L = 1.26 × 103 L⊙ and R = 37.5 R⊙, respectively. In the HR diagram, Polaris is located at the red edge of the instability strip.

  9. Evolutionary explanations for natural language: criteria from evolutionary biology

    NARCIS (Netherlands)

    Zuidema, W.; de Boer, B.

    2008-01-01

    Theories of the evolutionary origins of language must be informed by empirical and theoretical results from a variety of different fields. Complementing recent surveys of relevant work from linguistics, animal behaviour and genetics, this paper surveys the requirements on evolutionary scenarios that

  10. Active Tobacco Smoking and Distant Metastasis in Patients With Oropharyngeal Cancer

    Energy Technology Data Exchange (ETDEWEB)

    McBride, Sean M. [Harvard Radiation Oncology Program, Boston, Massachusetts (United States); Department of Radiation Oncology, Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts (United States); Ali, Nawal N. [Department of Radiation Oncology, Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts (United States); Margalit, Danielle N. [Harvard Radiation Oncology Program, Boston, Massachusetts (United States); Department of Radiation Oncology, Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts (United States); Chan, Annie W., E-mail: awchan@partners.org [Department of Radiation Oncology, Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts (United States)

    2012-09-01

    Purpose: Distant metastasis is the site of first relapse in approximately one-third of patients with locally advanced oropharyngeal carcinoma, irrespective of human papillomavirus status. Yet the risk factors associated with distant metastasis are not well characterized. We sought to characterize the relationship between smoking status and distant metastasis. Methods and Materials: We evaluated the association between tobacco smoking status and distant metastasis in a retrospective cohort study of 132 patients who underwent definitive radiation therapy and chemotherapy for Stage III-IVA/B oropharyngeal cancer. Information on tobacco smoking was prospectively collected by patient questionnaires and physician notes at the time of diagnosis. Thirty-three percent of the patients were nonsmokers, 51% were former smokers, 16% were active smokers. The cumulative lifetime tobacco smoking in pack-years was 20 (range, 0-150). Results: With a median follow-up time of 52 months, the overall rate of distant metastasis at 4 years was 8%. Distant metastasis was the most common first site of relapse, occurring in 56% of the patients with recurrences. Active smokers had higher rates of distant metastasis than non-active smokers (including never- and former smokers; 31% vs. 4%, p < 0.001) and former smokers (31% vs. 3%, p < 0.001). There was no statistically significant difference in the risk of distant metastasis for patients with lifetime cumulative pack-years >20 and {<=}20 (10% vs. 4%, p = 0.19). In univariate analysis, active smoking (p = 0.0004) and N category (p = 0.009) were predictive of increased risk of distant metastasis. In multivariate analysis, active smoking was the most significant predictive factor for increased risk of distant metastasis (hazard ratio, 12.7, p < 0.0001). Conclusions: This study identified a strong association between active smoking and distant metastasis in patients with oropharyngeal cancer.

  11. Evolutionary genomics of yeast pathogens in the Saccharomycotina

    Science.gov (United States)

    Naranjo-Ortíz, Miguel A.; Marcet-Houben, Marina

    2016-01-01

    Saccharomycotina comprises a diverse group of yeasts that includes numerous species of industrial or clinical relevance. Opportunistic pathogens within this clade are often assigned to the genus Candida but belong to phylogenetically distant lineages that also comprise non-pathogenic species. This indicates that the ability to infect humans has evolved independently several times among Saccharomycotina. Although the mechanisms of infection of the main groups of Candida pathogens are starting to be unveiled, we still lack sufficient understanding of the evolutionary paths that led to a virulent phenotype in each of the pathogenic lineages. Deciphering what genomic changes underlie the evolutionary emergence of a virulence trait will not only aid the discovery of novel virulence mechanisms but it will also provide valuable information to understand how new pathogens emerge, and what clades may pose a future danger. Here we review recent comparative genomics efforts that have revealed possible evolutionary paths to pathogenesis in different lineages, focusing on the main three agents of candidiasis worldwide: Candida albicans, C. parapsilosis and C. glabrata. We will discuss what genomic traits may facilitate the emergence of virulence, and focus on two different genome evolution mechanisms able to generate drastic phenotypic changes and which have been associated to the emergence of virulence: gene family expansion and interspecies hybridization. PMID:27493146

  12. A numerical experiment on light pollution from distant sources

    Science.gov (United States)

    Kocifaj, M.

    2011-08-01

    To predict the light pollution of the night-time sky realistically over any location or measuring point on the ground presents quite a difficult calculation task. Light pollution of the local atmosphere is caused by stray light, light loss or reflection of artificially illuminated ground objects or surfaces such as streets, advertisement boards or building interiors. Thus it depends on the size, shape, spatial distribution, radiative pattern and spectral characteristics of many neighbouring light sources. The actual state of the atmospheric environment and the orography of the surrounding terrain are also relevant. All of these factors together influence the spectral sky radiance/luminance in a complex manner. Knowledge of the directional behaviour of light pollution is especially important for the correct interpretation of astronomical observations. From a mathematical point of view, the light noise or veil luminance of a specific sky element is given by a superposition of scattered light beams. Theoretical models that simulate light pollution typically take into account all ground-based light sources, thus imposing great requirements on CPU and MEM. As shown in this paper, a contribution of distant sources to the light pollution might be essential under specific conditions of low turbidity and/or Garstang-like radiative patterns. To evaluate the convergence of the theoretical model, numerical experiments are made for different light sources, spectral bands and atmospheric conditions. It is shown that in the worst case the integration limit is approximately 100 km, but it can be significantly shortened for light sources with cosine-like radiative patterns.

  13. Distant cancer effects on standardised testing of peripheral vision.

    Science.gov (United States)

    Dawson, W W; Jordan, B L; Marsh, R D; Hazariwala, K; Flowers, F P; Fang, T

    2001-03-01

    Profound central-retinal visual losses have been a major presenting factor reported in cancer and melanoma associated retinopathies (CAR, MAR). However, it is well established that standardised tests of peripheral retinal function are often the most sensitive detectors of early eye disease. This is a preliminary investigation of the responsiveness of the peripheral retina to "distant" (non-eye or CNS) cancers using easily obtained standardised tests. The design is a single blind study where test results are compared with published norms and a small age matched control group. Of 120 ambulatory cancer outpatients who were interviewed at routine follow up examinations, 111 volunteered and admitted a range of mild visual changes. 25 cancer patients completed all tests of peripheral vision function and a clinical screening. There were seven control subjects of the same age range. 98% (49 of 50) of eyes from the patient cohort were judged clinically normal following examinations which emphasised the central retina, fundus appearance, and static fields. On testing which emphasised the visual periphery, 46 (92%) eyes showed one or more quantitative abnormalities >2 SD from the age adjusted norm means. These abnormalities clustered mainly about dark adaptation (rod cell) sensitivity (31, 62% of measured sites), the blue sensitive retinal cells (17, 34% of measured eyes), and the oscillatory component (OP) of the electroretinogram (23, 46% of measured eyes). One control eye (7%) showed a significant dark adaptation abnormality and ERG reduction. There was no identifiable interaction between chemotherapy mode and the cancer associated retinal deficits (CARD). Antiretinal antibodies were found in sera from most patients and controls. CARD is common in the retinal periphery of many cancer patients, and is distinct from rare CAR, MAR central-retinal responses. CARD has numerous potential clinical uses which justify expanded research with more defined large samples.

  14. APPLICATION OF MICROPHONE ARRAYS FOR DISTANT SPEECH CAPTURE

    Directory of Open Access Journals (Sweden)

    M. B. Stolbov

    2015-07-01

    Full Text Available Application of microphone arrays and beamforming techniques for speech information collection has significant advantages compared to systems operating with a single microphone. This paper presents a brief overview of microphone array systems for collecting distant speech information. The paper is based on an analysis of publications on the use of microphone arrays for speech information collection tasks, as well as on the author’s experience in the development and practical application of planar microphone arrays. The paper describes the main stages of the development of systems for remote capture of audio information. It provides a review of the main applications of microphone arrays, the basic types of microphone arrays and their features. The bulk of the paper deals with planar microphone arrays. We analyze the work of microphone arrays in different acoustic environments. The paper contains the basic equations for calculating the parameters of equidistant planar microphone arrays. Some methods of designing non-equidistant arrays are also mentioned (a list of references is included. We also provide a list of basic digital signal processing algorithms for planar microphone arrays, as well as a list of references on processing algorithms in the frequency domain. The paper includes a list of foreign companies offering systems based on microphone arrays for a wide range of tasks associated with the processing of speech and audio signals. We describe some state-of-the-art speech information collection systems based on microphone arrays. Some promising directions for the development of speech information collection systems using microphone arrays are described in conclusion. The material of the review is usable in designing of microphone arrays for specific practical applications.

  15. Imaging the mass structure of distant lens galaxies

    Science.gov (United States)

    Koopmans, Leon

    2005-07-01

    The surface brightness distribution of extended gravitationally lensed arcs and Einstein rings contains super-resolved information about the lensed object, and, more excitingly, about the smooth and clumpy mass distribution of the lens galaxies. The source and lens information can non-parametrically be separated, resulting in a direct "gravitational-mass image" of the inner mass-distribution of cosmologically-distant galaxies {Koopmans 2005}.With this goal in mind, we propose deep HST ACS-F555W/F814W and NICMOS-F160W imaging of 15 gravitational-lens systems with spatially resolved lensed sources, selected from the 17 new lens systems discovered by the Sloan Lens ACS Survey {Bolton et al. 2004}. Each system has been selected from the SDSS and confirmed in a time-efficient HST-ACS snapshot program {cycle-13}; they show highly-magnified arcs or Einstein rings, lensed by a massive early-type lens galaxy. High-fidelity multi-color HST images are required {not delivered by the 420-sec snapshot images} to isolate these lensed images {properly cleaned, dithered and extinction-corrected} from the lens galaxy surface brightness distribution, and apply our "gravitational-mass imaging" technique.The sample of galaxy mass distributions - determined through this method from the arcs and Einstein ring HST images - will be studied to: {i} measure the smooth mass distribution of the lens galaxies {Dark and luminous mass are separated using the HST images and the stellar M/L values derived from a joint stellar-dynamical analysis of each system}; {ii} quantify statistically and individually the incidence of mass-substructure {with or without obvious luminous counter-parts such as dwarf galaxies}. Since dark-matter substructure should be considerably more prevalent at higher redshift, both results provide a direct test of this prediction of the CDM hierarchical structure-formation model.

  16. Anxiety: an evolutionary approach.

    Science.gov (United States)

    Bateson, Melissa; Brilot, Ben; Nettle, Daniel

    2011-12-01

    Anxiety disorders are among the most common mental illnesses, with huge attendant suffering. Current treatments are not universally effective, suggesting that a deeper understanding of the causes of anxiety is needed. To understand anxiety disorders better, it is first necessary to understand the normal anxiety response. This entails considering its evolutionary function as well as the mechanisms underlying it. We argue that the function of the human anxiety response, and homologues in other species, is to prepare the individual to detect and deal with threats. We use a signal detection framework to show that the threshold for expressing the anxiety response ought to vary with the probability of threats occurring, and the individual's vulnerability to them if they do occur. These predictions are consistent with major patterns in the epidemiology of anxiety. Implications for research and treatment are discussed.

  17. Towards Adaptive Evolutionary Architecture

    DEFF Research Database (Denmark)

    Bak, Sebastian HOlt; Rask, Nina; Risi, Sebastian

    2016-01-01

    This paper presents first results from an interdisciplinary project, in which the fields of architecture, philosophy and artificial life are combined to explore possible futures of architecture. Through an interactive evolutionary installation, called EvoCurtain, we investigate aspects of how...... living in the future could occur, if built spaces could evolve and adapt alongside inhabitants. As such, present study explores the interdisciplinary possibilities in utilizing computational power to co-create with users and generate designs based on human input. We argue that this could lead...... to the development of designs tailored to the individual preferences of inhabitants, changing the roles of architects and designers entirely. Architecture-as-it-could-be is a philosophical approach conducted through artistic methods to anticipate the technological futures of human-centered development within...

  18. Topics of Evolutionary Computation 2001

    DEFF Research Database (Denmark)

    Ursem, Rasmus Kjær

    This booklet contains the student reports from the course: Topics of Evolutionary Computation, Fall 2001, given by Thiemo Krink, Rene Thomsen and Rasmus K. Ursem......This booklet contains the student reports from the course: Topics of Evolutionary Computation, Fall 2001, given by Thiemo Krink, Rene Thomsen and Rasmus K. Ursem...

  19. Open Issues in Evolutionary Robotics.

    Science.gov (United States)

    Silva, Fernando; Duarte, Miguel; Correia, Luís; Oliveira, Sancho Moura; Christensen, Anders Lyhne

    2016-01-01

    One of the long-term goals in evolutionary robotics is to be able to automatically synthesize controllers for real autonomous robots based only on a task specification. While a number of studies have shown the applicability of evolutionary robotics techniques for the synthesis of behavioral control, researchers have consistently been faced with a number of issues preventing the widespread adoption of evolutionary robotics for engineering purposes. In this article, we review and discuss the open issues in evolutionary robotics. First, we analyze the benefits and challenges of simulation-based evolution and subsequent deployment of controllers versus evolution on real robotic hardware. Second, we discuss specific evolutionary computation issues that have plagued evolutionary robotics: (1) the bootstrap problem, (2) deception, and (3) the role of genomic encoding and genotype-phenotype mapping in the evolution of controllers for complex tasks. Finally, we address the absence of standard research practices in the field. We also discuss promising avenues of research. Our underlying motivation is the reduction of the current gap between evolutionary robotics and mainstream robotics, and the establishment of evolutionary robotics as a canonical approach for the engineering of autonomous robots.

  20. Conceptual foundations of evolutionary thought

    Indian Academy of Sciences (India)

    K. P. MOHANAN

    2017-07-04

    Jul 4, 2017 ... This article seeks to explore the conceptual foundations of evolutionary thought in the physical, biological, and human sciences. Viewing evolution as symmetry breaking, it explores the concepts of change, history, and evolutionary history, and outlines a concept of biological macroevolution.

  1. Evolutionary dynamics in structured populations

    Science.gov (United States)

    Nowak, Martin A.; Tarnita, Corina E.; Antal, Tibor

    2010-01-01

    Evolutionary dynamics shape the living world around us. At the centre of every evolutionary process is a population of reproducing individuals. The structure of that population affects evolutionary dynamics. The individuals can be molecules, cells, viruses, multicellular organisms or humans. Whenever the fitness of individuals depends on the relative abundance of phenotypes in the population, we are in the realm of evolutionary game theory. Evolutionary game theory is a general approach that can describe the competition of species in an ecosystem, the interaction between hosts and parasites, between viruses and cells, and also the spread of ideas and behaviours in the human population. In this perspective, we review the recent advances in evolutionary game dynamics with a particular emphasis on stochastic approaches in finite sized and structured populations. We give simple, fundamental laws that determine how natural selection chooses between competing strategies. We study the well-mixed population, evolutionary graph theory, games in phenotype space and evolutionary set theory. We apply these results to the evolution of cooperation. The mechanism that leads to the evolution of cooperation in these settings could be called ‘spatial selection’: cooperators prevail against defectors by clustering in physical or other spaces. PMID:20008382

  2. Child Development and Evolutionary Psychology.

    Science.gov (United States)

    Bjorklund, David F.; Pellegrini, Anthony D.

    2000-01-01

    Argues that an evolutionary account provides insight into developmental function and individual differences. Outlines some assumptions of evolutionary psychology related to development. Introduces the developmental systems approach, differential influence of natural selection at different points in ontogeny, and development of evolved…

  3. Waiting for Shadows from the Distant Solar System

    Science.gov (United States)

    Kohler, Susanna

    2016-03-01

    How can we hope to measure the hundreds of thousands of objects in our distant solar system? A team of astronomers is harnessing citizen science to begin to tackle this problem!A light curve from an occultation collected by a RECON site in Quincy, California. As the objects shadow passes, the background stars light dims. [RECON/Charley Arrowsmith (Feather River College)]Occultation InformationEstimates currently place the number of Kuiper belt objects larger than 100 km across at over 100,000. Knowing the sizes and characteristics of these objects is important for understanding the composition of the outer solar system and constraining models of the solar systems formation and evolution.Unfortunately, measuring small, dim bodies at large distances is incredibly difficult! One of the best ways to obtain the sizes of these objects is to watch as they occult a distant star. Timing the object as it passes across the face of the star can give us a good measure of its size and shape, when observed from multiple stations in the path of the shadow.An Extended NetworkOccultations by nearby objects (like main-belt asteroids) can be predicted fairly accurately, but those by trans-Neptunian objects are much more poorly constrained. Only ~900 trans-Neptunian objects have approximately known paths, and occultation-shadow predictions for these objects are often only accurate to ~1000km on the Earths surface. So how can we ensure that theres a telescope in the right location, ready to observe when an occultation occurs?Map of the 56 RECON sites distributed over 2000 km in the western United States. [Buie et al. 2016]The simplest answer is to set up a huge network of observing stations, and wait for the shadows to come to the network. With this approach, even if the predicted path isnt precisely known, some of the stations will still observe the occultation.Due to the number of stations needed, this project lends itself perfectly to citizen science. In a recently published paper by

  4. Automatic Camera Control System for a Distant Lecture with Videoing a Normal Classroom.

    Science.gov (United States)

    Suganuma, Akira; Nishigori, Shuichiro

    The growth of a communication network technology enables students to take part in a distant lecture. Although many lectures are conducted in universities by using Web contents, normal lectures using a blackboard are still held. The latter style lecture is good for a teacher's dynamic explanation. A way to modify it for a distant lecture is to…

  5. A review of the genus Entisberus Distant (Hemiptera: Heteroptera: Rhyparochromidae: Drymini).

    Science.gov (United States)

    Scudder, G G E

    2016-02-18

    The genus Entisberus Distant is reviewed and illustrated and diagnostic characters listed. The type species, E. archetypus Distant is illustrated and diagnostic characteristics noted. The female of E. bergrothi Kondorosy is described for the first time. A new species, E. interruptus from Mindanao [Island] in the Republic of the Philippines, is described, and a revised key to the species of Entisberus is given.

  6. Computer constructed imagery of distant plasma interaction boundaries

    Energy Technology Data Exchange (ETDEWEB)

    Grenstadt, E.W.; Schurr, H.D.; Tsugawa, R.K.

    1982-01-01

    Computer constructed sketches of plasma boundaries arising from the interaction between the solar wind and the magnetosphere can serve as both didactic and research tools. In particular, the structure of the earth's bow shock can be represented as a nonuniform surfce according to the instantaneous orientation of the IMF, and temporal changes in structural distribution can be modeled as a sequence of sketches based on observed sequences of spacecraft-based measurements. Viewed rapidly, such a sequence of sketches can be the basis for representation of plasma processes by computer animation.

  7. Computer constructed imagery of distant plasma interaction boundaries

    Science.gov (United States)

    Greenstadt, E. W.; Schurr, H. D.; Tsugawa, R. K.

    Computer constructed sketches of plasma boundaries arising from the interaction between the solar wind and the magnetosphere can serve as both didactic and research tools. In particular, the structure of the earth's bow shock can be represented as a nonuniform surfce according to the instantaneous orientation of the IMF, and temporal changes in structural distribution can be modeled as a sequence of sketches based on observed sequences of spacecraft-based measurements. Viewed rapidly, such a sequence of sketches can be the basis for representation of plasma processes by computer animation.

  8. Evolutionary Explanations of Eating Disorders

    Directory of Open Access Journals (Sweden)

    Igor Kardum

    2008-12-01

    Full Text Available This article reviews several most important evolutionary mechanisms that underlie eating disorders. The first part clarifies evolutionary foundations of mental disorders and various mechanisms leading to their development. In the second part selective pressures and evolved adaptations causing contemporary epidemic of obesity as well as differences in dietary regimes and life-style between modern humans and their ancestors are described. Concerning eating disorders, a number of current evolutionary explanations of anorexia nervosa are presented together with their main weaknesses. Evolutionary explanations of eating disorders based on the reproductive suppression hypothesis and its variants derived from kin selection theory and the model of parental manipulation were elaborated. The sexual competition hypothesis of eating disorder, adapted to flee famine hypothesis as well as explanation based on the concept of social attention holding power and the need to belonging were also explained. The importance of evolutionary theory in modern conceptualization and research of eating disorders is emphasized.

  9. Adaptation and habitat selection in the eco-evolutionary process.

    Science.gov (United States)

    Morris, Douglas W

    2011-08-22

    The struggle for existence occurs through the vital rates of population growth. This basic fact demonstrates the tight connection between ecology and evolution that defines the emerging field of eco-evolutionary dynamics. An effective synthesis of the interdependencies between ecology and evolution is grounded in six principles. The mechanics of evolution specifies the origin and rules governing traits and evolutionary strategies. Traits and evolutionary strategies achieve their selective value through their functional relationships with fitness. Function depends on the underlying structure of variation and the temporal, spatial and organizational scales of evolution. An understanding of how changes in traits and strategies occur requires conjoining ecological and evolutionary dynamics. Adaptation merges these five pillars to achieve a comprehensive understanding of ecological and evolutionary change. I demonstrate the value of this world-view with reference to the theory and practice of habitat selection. The theory allows us to assess evolutionarily stable strategies and states of habitat selection, and to draw the adaptive landscapes for habitat-selecting species. The landscapes can then be used to forecast future evolution under a variety of climate change and other scenarios.

  10. Most Distant Group of Galaxies Known in the Universe

    Science.gov (United States)

    2002-04-01

    New VLT Discovery Pushes Back the Beginnings Summary Using the ESO Very Large Telescope (VLT) , a team of astronomers from The Netherlands, Germany, France and the USA [1] have discovered the most distant group of galaxies ever seen , about 13.5 billion light-years away. It has taken the light now recorded by the VLT about nine-tenths of the age of the Universe to cover the huge distance. We therefore observe those galaxies as they were at a time when the Universe was only about 10% of its present age . The astronomers conclude that this group of early galaxies will develop into a rich cluster of galaxies, such as those seen in the nearby Universe. The newly discovered structure provides the best opportunity so far for studying when and how galaxies began to form clusters after the initial Big Bang , one of the greatest puzzles in modern cosmology. PR Photo 11a/02 : Sky field with the distant cluster of galaxies. PR Photo 11b/02 : Spectra of some of the galaxies in the cluster. Radio Galaxies as cosmic signposts A most intriguing question in modern astronomy is how the first groupings or "clusters" of galaxies emerged from the gas produced in the Big Bang. Some theoretical models predict that densely populated galaxy clusters ("rich clusters" in current astronomical terminology) are built up through a step-wise process. Clumps develop in the primeval gas, and stars condense out of these clumps to form small galaxies. Then these small galaxies merge together to form larger units. The peculiar class of "radio galaxies" is particularly important for investigating such scenarios. They are called so because their radio emission - a result of violent processes believed to be related to massive black holes located at the centres of these galaxies - is stronger by 5 - 10 orders of magnitude than that of our own Milky Way galaxy. In fact, this radio emission is often so intense that the galaxies can be spotted at extremely large distances, and thus at the remote epoch when

  11. Non-Chemical Distant Cellular Interactions as a potential confounder of Cell Biology Experiments

    Directory of Open Access Journals (Sweden)

    Ashkan eFarhadi

    2014-10-01

    Full Text Available Distant cells can communicate with each other through a variety of methods. Two such methods involve electrical and/or chemical mechanisms. Non-chemical, distant cellular interactions may be another method of communication that cells can use to modify the behavior of other cells that are mechanically separated. Moreover, non-chemical, distant cellular interactions may explain some cases of confounding effects in Cell Biology experiments. In this article, we review non-chemical, distant cellular interactions studies to try to shed light on the mechanisms in this highly unconventional field of cell biology. Despite the existence of several theories that try to explain the mechanism of non-chemical, distant cellular interactions, this phenomenon is still speculative. Among candidate mechanisms, electromagnetic waves appear to have the most experimental support. In this brief article, we try to answer a few key questions that may further clarify this mechanism.

  12. Cenozoic climate change influences mammalian evolutionary dynamics.

    Science.gov (United States)

    Figueirido, Borja; Janis, Christine M; Pérez-Claros, Juan A; De Renzi, Miquel; Palmqvist, Paul

    2012-01-17

    Global climate change is having profound impacts on the natural world. However, climate influence on faunal dynamics at macroevolutionary scales remains poorly understood. In this paper we investigate the influence of climate over deep time on the diversity patterns of Cenozoic North American mammals. We use factor analysis to identify temporally correlated assemblages of taxa, or major evolutionary faunas that we can then study in relation to climatic change over the past 65 million years. These taxa can be grouped into six consecutive faunal associations that show some correspondence with the qualitative mammalian chronofaunas of previous workers. We also show that the diversity pattern of most of these chronofaunas can be correlated with the stacked deep-sea benthic foraminiferal oxygen isotope (δ(18)O) curve, which strongly suggests climatic forcing of faunal dynamics over a large macroevolutionary timescale. This study demonstrates the profound influence of climate on the diversity patterns of North American terrestrial mammals over the Cenozoic.

  13. Evolutionary analysis of DNA-protein-coding regions based on a genetic code cube metric.

    Science.gov (United States)

    Sanchez, Robersy

    2014-01-01

    The right estimation of the evolutionary distance between DNA or protein sequences is the cornerstone of the current phylogenetic analysis based on distance methods. Herein, it is demonstrated that the Manhattan distance (dw), weighted by the evolutionary importance of the nucleotide bases in the codon, is a naturally derived metric in the standard genetic code cube inserted into the three-dimensional Euclidean space. Based on the application of distance dw, a novel evolutionary model is proposed. This model includes insertion/deletion mutations that are very important for cancer studies, but usually discarded in classical evolutionary models. In this study, the new evolutionary model was applied to the phylogenetic analysis of the DNA protein-coding regions of 13 mammal mitochondrial genomes and of four cancer genetic- susceptibility genes (ATM, BRCA1, BRCA2 and p53) from nine mammals. The opossum (a marsupial) was used as an out-group species for both sets of sequences. The new evolutionary model yielded the correct topology, while the current models failed to separate the evolutionarily distant species of mouse and opossum.

  14. SU-F-R-46: Predicting Distant Failure in Lung SBRT Using Multi-Objective Radiomics Model

    Energy Technology Data Exchange (ETDEWEB)

    Zhou, Z; Folkert, M; Iyengar, P; Zhang, Y; Wang, J [UT Southwestern Medical Center, Dallas, TX (United States)

    2016-06-15

    Purpose: To predict distant failure in lung stereotactic body radiation therapy (SBRT) in early stage non-small cell lung cancer (NSCLC) by using a new multi-objective radiomics model. Methods: Currently, most available radiomics models use the overall accuracy as the objective function. However, due to data imbalance, a single object may not reflect the performance of a predictive model. Therefore, we developed a multi-objective radiomics model which considers both sensitivity and specificity as the objective functions simultaneously. The new model is used to predict distant failure in lung SBRT using 52 patients treated at our institute. Quantitative imaging features of PET and CT as well as clinical parameters are utilized to build the predictive model. Image features include intensity features (9), textural features (12) and geometric features (8). Clinical parameters for each patient include demographic parameters (4), tumor characteristics (8), treatment faction schemes (4) and pretreatment medicines (6). The modelling procedure consists of two steps: extracting features from segmented tumors in PET and CT; and selecting features and training model parameters based on multi-objective. Support Vector Machine (SVM) is used as the predictive model, while a nondominated sorting-based multi-objective evolutionary computation algorithm II (NSGA-II) is used for solving the multi-objective optimization. Results: The accuracy for PET, clinical, CT, PET+clinical, PET+CT, CT+clinical, PET+CT+clinical are 71.15%, 84.62%, 84.62%, 85.54%, 82.69%, 84.62%, 86.54%, respectively. The sensitivities for the above seven combinations are 41.76%, 58.33%, 50.00%, 50.00%, 41.67%, 41.67%, 58.33%, while the specificities are 80.00%, 92.50%, 90.00%, 97.50%, 92.50%, 97.50%, 97.50%. Conclusion: A new multi-objective radiomics model for predicting distant failure in NSCLC treated with SBRT was developed. The experimental results show that the best performance can be obtained by combining

  15. Generation of heralded entanglement between distant quantum dot hole spins

    Science.gov (United States)

    Delteil, Aymeric

    Entanglement plays a central role in fundamental tests of quantum mechanics as well as in the burgeoning field of quantum information processing. Particularly in the context of quantum networks and communication, some of the major challenges are the efficient generation of entanglement between stationary (spin) and propagating (photon) qubits, the transfer of information from flying to stationary qubits, and the efficient generation of entanglement between distant stationary (spin) qubits. In this talk, I will present such experimental implementations achieved in our team with semiconductor self-assembled quantum dots.Not only are self-assembled quantum dots good single-photon emitters, but they can host an electron or a hole whose spin serves as a quantum memory, and then present spin-dependent optical selection rules leading to an efficient spin-photon quantum interface. Moreover InGaAs quantum dots grown on GaAs substrate can profit from the maturity of III-V semiconductor technology and can be embedded in semiconductor structures like photonic cavities and Schottky diodes.I will report on the realization of heralded quantum entanglement between two semiconductor quantum dot hole spins separated by more than five meters. The entanglement generation scheme relies on single photon interference of Raman scattered light from both dots. A single photon detection projects the system into a maximally entangled state. We developed a delayed two-photon interference scheme that allows for efficient verification of quantum correlations. Moreover the efficient spin-photon interface provided by self-assembled quantum dots allows us to reach an unprecedented rate of 2300 entangled spin pairs per second, which represents an improvement of four orders of magnitude as compared to prior experiments carried out in other systems.Our results extend previous demonstrations in single trapped ions or neutral atoms, in atom ensembles and nitrogen vacancy centers to the domain of

  16. Verbalizations Affect Visuomotor Control in Hitting Objects to Distant Targets

    Directory of Open Access Journals (Sweden)

    Simone Caljouw

    2017-04-01

    Full Text Available There is a long-standing proposal for the existence of two neuroanatomically and functionally separate visual systems; one supported by the dorsal pathway to control action and the second supported by the ventral pathway to handle explicit perceptual judgments. The dorsal pathway requires fast access to egocentric information, while the ventral pathway primarily requires allocentric information. Despite the evidence for functionally distinct systems, researchers have posited important interactions. This paper examines evidence to what degree the interaction becomes more important when target-identity, the perception of which is supported by the ventral stream, is verbalized during the execution of a target-directed far-aiming movement. In the experiment reported here participants hit balls toward distant targets while concurrently making explicit perceptual judgments of target properties. The endpoint of a shaft served as the target, with conditions including illusory arrow fins at the endpoint. Participants verbalized the location of the target by comparing it to a reference line and calling out “closer” or “further” while propelling the ball to the target. The impact velocity at ball contact was compared for hits toward three shafts of lengths, 94, 100, and 106 cm, with and without verbalizations and delays. It was observed that the meaning of the expressed words modulated movement execution when the verbalizations were consistent with the action characteristics. This effect of semantic content was evident regardless of target visibility during movement execution, demonstrating it was not restricted to movements that rely on visual memory. In addition to a direct effect of semantic content we anticipated an indirect effect of verbalization to result in action shifting toward the use of context-dependent allocentric information. This would result in an illusion bias on the impact velocity when the target is embedded in a M

  17. Time Matters: Framing Antismoking Messages Using Current Smokers' Preexisting Perceptions of Temporal Distance to Smoking-Related Health Risks.

    Science.gov (United States)

    Kim, Kyongseok; Kim, Hyang-Sook

    2017-01-17

    This study examined the effects of temporal framing used in messages about the future likelihood of developing smoking-related diseases on intention to quit smoking. Based on construal level theory (CLT), a causal model delineating the relationships among four variables-perceived temporal distance, personal relevance, perceived susceptibility, and behavioral intention-was proposed. The model was validated by an online experiment with a sample of 222 current smokers, revealing the effects of perceived temporal distance on behavioral intention via personal relevance and perceived susceptibility. Following the CLT-grounded model, the effects of different temporal frames (near future vs. distant future) on the four variables were tested. The near-future frame featured a risk perceived to be more temporally proximal (i.e., heart attack), and the distant-future frame featured a risk perceived to be more temporally distant (i.e., larynx cancer) among current smokers. Participants exposed to the near-future frame reported significantly shorter perceived temporal distance, greater personal relevance and perceived susceptibility to the risk portrayed in the message, and greater intention to quit smoking than participants exposed to the distant-future frame. Implications for antismoking communications are discussed.

  18. Chandra Survey of Distant Galaxies Provides Evidence for Vigorous Starbursts

    Science.gov (United States)

    2000-05-01

    Using NASA's Chandra X-ray Observatory, astronomers have made the first long-duration X-ray survey of the Hubble Deep Field North. They detected X rays from six of the galaxies in the field, and were surprised by the lack of X rays from some of the most energetic galaxies in the field. The X-ray emitting objects discovered by the research team are a distant galaxy thought to contain a central giant black hole, three elliptically shaped galaxies, an extremely red distant galaxy, and a nearby spiral galaxy. "We were expecting about five X-ray sources in this field,"said Professor Niel Brandt of Penn State University, University Park, and one of the leaders of the research team that conducted the survey. "However, it was very surprising to find that none of the X-ray sources lined up with any of the submillimeter sources." The submillimeter sources are extremely luminous, dusty galaxies that produce large amounts of infrared radiation. Because they are over ten billion light years from Earth, their infrared radiation is shifted to longer, submillimeter wavelengths as it traverses the expanding universe. The primary source of the large power of the submillimeter sources is thought to be an unusually high rate of star formation, or the infall, or accretion of matter into a giant black hole in the center of the galaxy. X-ray observations provide the most direct measure of black hole accretion power. X rays, because of their high-energy, would be expected to pass through the gas and dust in these galaxies, unlike visible light. "With Chandra we have been able to place the best X-ray constraints ever on submillimeter sources," said Ann Hornschemeier, also of Penn State, and the lead author of an upcoming Astrophysical Journal paper describing the discovery. "Our results indicate that less than 15 percent of the submillimeter sources can be luminous X-ray sources." "That means," Brandt explains, "Either there is an enormous amount of star formation in those galaxies, or

  19. Industrial Applications of Evolutionary Algorithms

    CERN Document Server

    Sanchez, Ernesto; Tonda, Alberto

    2012-01-01

    This book is intended as a reference both for experienced users of evolutionary algorithms and for researchers that are beginning to approach these fascinating optimization techniques. Experienced users will find interesting details of real-world problems, and advice on solving issues related to fitness computation, modeling and setting appropriate parameters to reach optimal solutions. Beginners will find a thorough introduction to evolutionary computation, and a complete presentation of all evolutionary algorithms exploited to solve different problems. The book could fill the gap between the

  20. Towards General Temporal Aggregation

    DEFF Research Database (Denmark)

    Boehlen, Michael H.; Gamper, Johann; Jensen, Christian Søndergaard

    2008-01-01

    Most database applications manage time-referenced, or temporal, data. Temporal data management is difficult when using conventional database technology, and many contributions have been made for how to better model, store, and query temporal data. Temporal aggregation illustrates well the problem...

  1. Evolutionary biology redux.

    Science.gov (United States)

    Torday, John S

    2013-01-01

    This article offers a novel, enlightened concept for determining the mechanism of evolution. It is based on homeostasis, which distinguishes life from non-life and as such is the universal mechanism for the evolution of all living organisms. This view of evolution is logical, mechanistic, non-scalar, predictive, testable, and falsifiable, and it illuminates the epistemological relationships between physics and biology, ontogeny and phylogeny, development and aging, ultimate and proximate causation, health and disease. In addition to validating Haeckel's biogenetic law and Lamarckian epigenetics, reflecting the enabling value of the cellular approach, this perspective also expresses the evolutionary process at the cell-molecular level, since the mechanism of cell communication itself is universal in biology, in keeping with a Kuhnian paradigm shift. This approach may even elucidate the nature and evolution of consciousness as a manifestation of the cellular continuum from unicellular to multicellular life. We need such a functional genomic mechanism for the process of evolution if we are to make progress in biology and medicine. Like Copernican heliocentrism, a cellular approach to evolution may fundamentally change humankind's perceptions about our place in the universe.

  2. Risk Factors for Distant Metastasis in Patients with Minimally Invasive Follicular Thyroid Carcinoma.

    Directory of Open Access Journals (Sweden)

    Yu-Mi Lee

    Full Text Available Although patients with minimally invasive follicular thyroid carcinoma (MIFTC generally have an excellent prognosis, distant metastasis occurs in some patients. Risk factors for distant metastasis have been reported, none has been found to be conclusive. This study evaluated risk factors for distant metastasis, including protein markers, in patients with MIFTC.A review of patient records identified 259 patients who underwent surgery at Asan Medical Center from 1996 to 2010 and were subsequently diagnosed with MIFTC. After review of pathological slides, 120 patients with paraffin blocks suited for tissue microarrays (TMA were included in this study. Immunohistochemical stain of TMA slides was performed by protein markers; β-catenin, C-MET, CK19, estrogen receptor (ER α, ER β, HBME-1, MMP2, PPAR γ and progesterone receptor.120 patients included 28 males (23.3% and 92 females (76.7%, of mean age 41.5±10.8 years (range, 13-74 years. Eight patients (6.7% had distant metastases during follow-up. Univariate analysis showed that age (≥45 years, male sex, and extensive vascular invasion (≥4 foci were associated with distant metastasis. Multivariate regression analysis showed that extensive vascular invasion was the only independent risk factor for distant metastasis (p = 0.012. Although no protein markers on TMA analysis were directly related to distant metastasis of MIFTC, CK19 expression was more frequent in patients with than without extensive vascular invasion (p = 0.036.Extensive vascular invasion was the only independent risk factor for distant metastasis of MIFTC. No proteins markers were directly related to distant metastasis, but CK19 was associated with extensive vascular invasion.

  3. Clearing the Cosmic Fog - The Most Distant Galaxy Ever Measured

    Science.gov (United States)

    2010-10-01

    distances to such faint and remote objects is an enormous challenge and can only reliably be done using spectroscopy from very large ground-based telescopes [4], by measuring the redshift of the galaxy's light. Matt Lehnert takes up the story: "After the announcement of the candidate galaxies from Hubble we did a quick calculation and were excited to find that the immense light collecting power of the VLT, when combined with the sensitivity of the infrared spectroscopic instrument, SINFONI, and a very long exposure time might just allow us to detect the extremely faint glow from one of these remote galaxies and to measure its distance." On special request to ESO's Director General they obtained telescope time on the VLT and observed a candidate galaxy called UDFy-38135539 [5] for 16 hours. After two months of very careful analysis and testing of their results, the team found that they had clearly detected the very faint glow from hydrogen at a redshift of 8.6, which makes this galaxy the most distant object ever confirmed by spectroscopy. A redshift of 8.6 corresponds to a galaxy seen just 600 million years after the Big Bang. Co-author Nicole Nesvadba (Institut d'Astrophysique Spatiale) sums up this work, "Measuring the redshift of the most distant galaxy so far is very exciting in itself, but the astrophysical implications of this detection are even more important. This is the first time we know for sure that we are looking at one of the galaxies that cleared out the fog which had filled the very early Universe." One of the surprising things about this discovery is that the glow from UDFy-38135539 seems not to be strong enough on its own to clear out the hydrogen fog. "There must be other galaxies, probably fainter and less massive nearby companions of UDFy-38135539, which also helped make the space around the galaxy transparent. Without this additional help the light from the galaxy, no matter how brilliant, would have been trapped in the surrounding hydrogen fog and we

  4. Evolutionary computation for reinforcement learning

    NARCIS (Netherlands)

    Whiteson, S.; Wiering, M.; van Otterlo, M.

    2012-01-01

    Algorithms for evolutionary computation, which simulate the process of natural selection to solve optimization problems, are an effective tool for discovering high-performing reinforcement-learning policies. Because they can automatically find good representations, handle continuous action spaces,

  5. Integrating genomics into evolutionary medicine.

    Science.gov (United States)

    Rodríguez, Juan Antonio; Marigorta, Urko M; Navarro, Arcadi

    2014-12-01

    The application of the principles of evolutionary biology into medicine was suggested long ago and is already providing insight into the ultimate causes of disease. However, a full systematic integration of medical genomics and evolutionary medicine is still missing. Here, we briefly review some cases where the combination of the two fields has proven profitable and highlight two of the main issues hindering the development of evolutionary genomic medicine as a mature field, namely the dissociation between fitness and health and the still considerable difficulties in predicting phenotypes from genotypes. We use publicly available data to illustrate both problems and conclude that new approaches are needed for evolutionary genomic medicine to overcome these obstacles. Copyright © 2014 Elsevier Ltd. All rights reserved.

  6. Phenotypical Behavior and Evolutionary Slavery

    OpenAIRE

    Martins, Andre C. R.

    2000-01-01

    A new evolutionary solution to Prisoner Dilemma situations is proposed in this paper. A specific genetic code may have different phenotypes, meaning different strategies for different individuals carrying that gene. This means that, under the right parameters, it is a good evolutionary solution to create two types of phenotypes with different strategies, here called as leaders and servants. In this solution, servants always cooperate with the leaders and leaders never do with the servants. In...

  7. Optimal Control of Evolutionary Dynamics

    CERN Document Server

    Chakrabarti, Raj; McLendon, George

    2008-01-01

    Elucidating the fitness measures optimized during the evolution of complex biological systems is a major challenge in evolutionary theory. We present experimental evidence and an analytical framework demonstrating how biochemical networks exploit optimal control strategies in their evolutionary dynamics. Optimal control theory explains a striking pattern of extremization in the redox potentials of electron transport proteins, assuming only that their fitness measure is a control objective functional with bounded controls.

  8. Evolutionary Origin of Euglena.

    Science.gov (United States)

    Zakryś, Bożena; Milanowski, Rafał; Karnkowska, Anna

    2017-01-01

    Euglenids (Excavata, Discoba, Euglenozoa, Euglenida) is a group of free-living, single-celled flagellates living in the aquatic environments. The uniting and unique morphological feature of euglenids is the presence of a cell covering called the pellicle. The morphology and organization of the pellicle correlate well with the mode of nutrition and cell movement. Euglenids exhibit diverse modes of nutrition, including phagotrophy and photosynthesis. Photosynthetic species (Euglenophyceae) constitute a single subclade within euglenids. Their plastids embedded by three membranes arose as the result of a secondary endosymbiosis between phagotrophic eukaryovorous euglenid and the Pyramimonas-related green alga. Within photosynthetic euglenids three evolutionary lineages can be distinguished. The most basal lineage is formed by one mixotrophic species, Rapaza viridis. Other photosynthetic euglenids are split into two groups: predominantly marine Eutreptiales and freshwater Euglenales. Euglenales are divided into two families: Phacaceae, comprising three monophyletic genera (Discoplastis, Lepocinclis, Phacus) and Euglenaceae with seven monophyletic genera (Euglenaformis, Euglenaria, Colacium, Cryptoglena, Strombomonas, Trachelomonas, Monomorphina) and polyphyletic genus Euglena. For 150 years researchers have been studying Euglena based solely on morphological features what resulted in hundreds of descriptions of new taxa and many artificial intra-generic classification systems. In spite of the progress towards defining Euglena, it still remains polyphyletic and morphologically almost undistinguishable from members of the recently described genus Euglenaria; members of both genera have cells undergoing metaboly (dynamic changes in cell shape), large chloroplasts with pyrenoids and monomorphic paramylon grains. Model organisms Euglena gracilis Klebs, the species of choice for addressing fundamental questions in eukaryotic biochemistry, cell and molecular biology, is a

  9. Molluscan Evolutionary Genomics

    Energy Technology Data Exchange (ETDEWEB)

    Simison, W. Brian; Boore, Jeffrey L.

    2005-12-01

    In the last 20 years there have been dramatic advances in techniques of high-throughput DNA sequencing, most recently accelerated by the Human Genome Project, a program that has determined the three billion base pair code on which we are based. Now this tremendous capability is being directed at other genome targets that are being sampled across the broad range of life. This opens up opportunities as never before for evolutionary and organismal biologists to address questions of both processes and patterns of organismal change. We stand at the dawn of a new 'modern synthesis' period, paralleling that of the early 20th century when the fledgling field of genetics first identified the underlying basis for Darwin's theory. We must now unite the efforts of systematists, paleontologists, mathematicians, computer programmers, molecular biologists, developmental biologists, and others in the pursuit of discovering what genomics can teach us about the diversity of life. Genome-level sampling for mollusks to date has mostly been limited to mitochondrial genomes and it is likely that these will continue to provide the best targets for broad phylogenetic sampling in the near future. However, we are just beginning to see an inroad into complete nuclear genome sequencing, with several mollusks and other eutrochozoans having been selected for work about to begin. Here, we provide an overview of the state of molluscan mitochondrial genomics, highlight a few of the discoveries from this research, outline the promise of broadening this dataset, describe upcoming projects to sequence whole mollusk nuclear genomes, and challenge the community to prepare for making the best use of these data.

  10. Temporal and spatial neural dynamics in the perception of basic emotions from complex scenes

    NARCIS (Netherlands)

    Costa, T.; Cauda, F.; Crini, M.; Tatu, M.K.; Celeghin, A.; de Gelder, B.; Tamietto, M.

    2014-01-01

    The different temporal dynamics of emotions are critical to understand their evolutionary role in the regulation of interactions with the surrounding environment. Here, we investigated the temporal dynamics underlying the perception of four basic emotions from complex scenes varying in valence and

  11. Evolutionary biology and life histories

    Directory of Open Access Journals (Sweden)

    Brown, C. R.

    2004-06-01

    Full Text Available The demographic processes that drive the spread of populations through environments and in turn determine the abundance of organisms are the same demographic processes that drive the spread of genes through populations and in turn determine gene frequencies and fitness. Conceptually, marked similarities exist in the dynamic processes underlying population ecology and those underlying evolutionary biology. Central to an understanding of both disciplines is life history and its component demographic rates, such as survival, fecundity, and age of first breeding, and biologists from both fields have a vested interest in good analytical machinery for the estimation and analysis of these demographic rates. In the EURING conferences, we have been striving since the mid 1980s to promote a quantitative understanding of demographic rates through interdisciplinary collaboration between ecologists and statisticians. From the ecological side, the principal impetus has come from population biology, and in particular from wildlife biology, but the importance of good quantitative insights into demographic processes has long been recognized by a number of evolutionary biologists (e.g., Nichols & Kendall, 1995; Clobert, 1995; Cooch et al., 2002. In organizing this session, we have aimed to create a forum for those committed to gaining the best possible understanding of evolutionary processes through the application of modern quantitative methods for the collection and interpretation of data on marked animal populations. Here we present a short overview of the material presented in the session on evolutionary biology and life histories. In a plenary talk, Brown & Brown (2004 explored how mark–recapture methods have allowed a better understanding of the evolution of group–living and alternative reproductive tactics in colonial cliff swallows (Petrochelidon pyrrhonota. By estimating the number of transient birds passing through colonies of different sizes, they

  12. P-30 Evaluation of Avatar Mediated Distant-care System by the Elderly

    National Research Council Canada - National Science Library

    Hasegawa, Dai; Yokoyama, Naoki; Morikawa, Hiroyuki; Nakayama, Eijun; Sakuta, Hiroshi

    2017-01-01

    ...’ healthy life expectancy. And under such circumstances, a novel approach of distant-care system has been proposed, in which the elderly persons are represented by an avatar, protecting their privacy...

  13. Hedonic Benefits of Close and Distant Interaction Partners: The Mediating Roles of Social Approval and Authenticity.

    Science.gov (United States)

    Venaglia, Rachel B; Lemay, Edward P

    2017-09-01

    The current research utilized ecological momentary assessment methodology to examine affective responses to interacting with close versus distant interaction partners during naturally occurring social interactions, and to test predictions regarding the mediating roles of perceived social approval and authenticity. Analysis of 4,602 social interactions reported by 176 participants suggested that, relative to interactions with distant partners, interactions with close partners were characterized by more positive affect. This effect was mediated by perceived social approval and authenticity. These findings suggest that social interactions with close others confer greater hedonic benefits relative to interactions with distant partners due to greater confidence in social approval and feelings of authenticity. Exploratory analyses suggested that interactions with close partners featured warmer and less shy behavior, and that participants who placed more importance on close relationships (as measured by high relational-interdependent self-construal) experienced more approval and authenticity in their interactions, particularly with distant partners.

  14. Markers of progression in early-stage invasive breast cancer: a predictive immunohistochemical panel algorithm for distant recurrence risk stratification.

    Science.gov (United States)

    Aleskandarany, Mohammed A; Soria, D; Green, A R; Nolan, C; Diez-Rodriguez, Maria; Ellis, I O; Rakha, E A

    2015-06-01

    Accurate distant metastasis (DM) prediction is critical for risk stratification and effective treatment decisions in breast cancer (BC). Many prognostic markers/models based on tissue marker studies are continually emerging using conventional statistical approaches analysing complex/dimensional data association with DM/poor prognosis. However, few of them have fulfilled satisfactory evidences for clinical application. This study aimed at building DM risk assessment algorithm for BC patients. A well-characterised series of early invasive primary operable BC (n = 1902), with immunohistochemical expression of a panel of biomarkers (n = 31) formed the material of this study. Decision tree algorithm was computed using WEKA software, utilising quantitative biomarkers' expression and the absence/presence of distant metastases. Fifteen biomarkers were significantly associated with DM, with six temporal subgroups characterised based on time to development of DM ranging from 15 years of follow-up. Of these 15 biomarkers, 10 had a significant expression pattern where Ki67LI, HER2, p53, N-cadherin, P-cadherin, PIK3CA and TOMM34 showed significantly higher expressions with earlier development of DM. In contrast, higher expressions of ER, PR and BCL2 were associated with delayed occurrence of DM. DM prediction algorithm was built utilising cases informative for the 15 significant markers. Four risk groups of patients were characterised. Three markers p53, HER2 and BCL2 predicted the probability of DM, based on software-generated cut-offs, with a precision rate of 81.1 % for positive predictive value and 77.3 %, for the negative predictive value. This algorithm reiterates the reported prognostic values of these three markers and underscores their central biological role in BC progression. Further independent validation of this pruned panel of biomarkers is therefore warranted.

  15. Hemifacial Spasm Due to a Large Distant Ipsilateral Posterior Fossa Meningioma

    OpenAIRE

    Harrison, Gregory S.; Chovan, Peter; Lee, Joung H.

    2000-01-01

    A rare case of hemifacial spasm due to an ipsilateral foramen magnum/clival meningioma is described. Magnetic resonance imaging demonstrated that the tumor was located distant to the cranial nerve VII/VIII complex. Resolution of the ipsilateral hemifacial spasm was noted after complete resection of the tumor. The mechanism of hemifacial spasm was likely due to displacement and distortion of the brain stem from the lesion distant to the cranial nerve VII/VIII complex. In our review of the lite...

  16. Treatment of distant metastases from follicular cell-derived thyroid cancer.

    Science.gov (United States)

    Schlumberger, Martin; Leboulleux, Sophie

    2015-01-01

    Distant metastases from thyroid cancer of follicular origin are uncommon. Treatment includes levothyroxine administration at suppressive doses, focal treatment modalities with surgery, external radiation therapy and thermal ablation, and radioiodine in patients with uptake of (131)I in their metastases. Two thirds of distant metastases will become refractory to radioiodine at some point, and when there is a significant tumor burden and documented progression on imaging, a treatment with a kinase inhibitor may provide benefits.

  17. Analysis of loco-regional and distant recurrences in breast cancer after conservative surgery.

    Science.gov (United States)

    Elsayed, Mostafa; Alhussini, Mahmoud; Basha, Ahmed; Awad, A T

    2016-05-14

    A number of patients treated conservatively for breast cancer will develop loco-regional and distant recurrences. Our aim was to determine how their occurrence may be linked to the evolution of the disease. We analyzed 238 women treated by conservative breast surgery and breast irradiation in a single institution. We evaluated the prognostic factors associated with loco-regional and distant recurrences and the prognostic value of local and regional recurrences on systemic progression. After a median follow-up of 5 year (range 1-10), 16 (6.72%) patients in the breast conservative surgery (BCS) groups had loco-regional recurrence. For distant recurrence, 10 (4.2%) patients had experienced distant recurrence. Lympho-vascular invasion (HR 2.55; 95% CI, 076 to 8.49) and an extensive intraductal component (HR, 2.22; 95% CI, 0.69 to 7.15) and nodal status are risk factors for loco-regional recurrence (LRR) after breast conservative therapy (BCT). Tumor size, nodal status, high histologic grade, and breast cancer diagnosed at a young age (≤35 years) are correlated with higher distant recurrence rates after BCT. Risk factors for LRR after BCS include lympho-vascular invasion, extensive inraductal component, and high nodal status, where as risk factors for distant recurrence include tumor size, nodal status, high histologic grade, and breast cancer diagnosed at a young age (≤35 years).

  18. Prognostic aspects of dynamic contrast-enhanced magnetic resonance imaging in synchronous distant metastatic rectal cancer

    Energy Technology Data Exchange (ETDEWEB)

    Yu, Jing; Xu, Qing; Song, Jia-Cheng; Li, Yan; Xu, Lu-Lu; Shi, Hai-Bin [First Affiliated Hospital of Nanjing Medical University, Department of Radiology, Nanjing (China); Huang, Dong-Ya [First Affiliated Hospital of Nanjing Medical University, Department of General Surgery, Nanjing (China)

    2017-05-15

    To explore the correlations between DCE-MRI quantitative parameters and synchronous distant metastasis and the clinicopathological factors in rectal cancers. Sixty-three patients with rectal cancer (synchronous distant metastasis, n = 31; non-metastasis, n = 32) were enrolled in this study. Student's t test and ANOVA were used to compare DCE-MRI parameters (K{sup trans}, K{sub ep} and V{sub e}). The receiver operating characteristic (ROC) analysis was used to find the reasonable threshold of DCE-MRI parameters to differentiate lesions with synchronous distant metastasis from those without metastasis. The K{sup trans}, K{sub ep}, and V{sub e} value were significantly higher in the lesions with distant metastasis than in the lesions without distant metastasis (0.536 ± 0.242 vs. 0.299 ± 0.118 min{sup -1}, p < 0.001; 1.598 ± 0.477 vs. 1.341 ± 0.390 min{sup -1}, p = 0.022; and 0.324 ± 0.173 vs. 0.249 ± 0.091, p = 0.034; respectively). The K{sup trans} showed the highest AUCs of 0.788 (p < 0.001), with sensitivity of 61.29 % and specificity of 87.5 %, respectively. DCE-MRI parameters may represent a prognostic indicator for synchronous distant metastases in patients with rectal cancer. (orig.)

  19. Semantics of Temporal Models with Multiple Temporal Dimensions

    DEFF Research Database (Denmark)

    Kraft, Peter; Sørensen, Jens Otto

    Semantics of temporal models with multi temporal dimensions are examined progressing from non-temporal models unto uni-temporal, and further unto bi- and tri-temporal models. An example of a uni-temporal model is the valid time model, an example of a bi-temporal model is the valid time/transactio...

  20. Wolves (Canis lupus) and dogs (Canis familiaris) differ in following human gaze into distant space but respond similar to their packmates' gaze.

    Science.gov (United States)

    Werhahn, Geraldine; Virányi, Zsófia; Barrera, Gabriela; Sommese, Andrea; Range, Friederike

    2016-08-01

    Gaze following into distant space is defined as visual co-orientation with another individual's head direction allowing the gaze follower to gain information on its environment. Human and nonhuman animals share this basic gaze following behavior, suggested to rely on a simple reflexive mechanism and believed to be an important prerequisite for complex forms of social cognition. Pet dogs differ from other species in that they follow only communicative human gaze clearly addressed to them. However, in an earlier experiment we showed that wolves follow human gaze into distant space. Here we set out to investigate whether domestication has affected gaze following in dogs by comparing pack-living dogs and wolves raised and kept under the same conditions. In Study 1 we found that in contrast to the wolves, these dogs did not follow minimally communicative human gaze into distant space in the same test paradigm. In the observational Study 2 we found that pack-living dogs and wolves, similarly vigilant to environmental stimuli, follow the spontaneous gaze of their conspecifics similarly often. Our findings suggest that domestication did not affect the gaze following ability of dogs itself. The results raise hypotheses about which other dog skills might have been altered through domestication that may have influenced their performance in Study 1. Because following human gaze in dogs might be influenced by special evolutionary as well as developmental adaptations to interactions with humans, we suggest that comparing dogs to other animal species might be more informative when done in intraspecific social contexts. (PsycINFO Database Record (c) 2016 APA, all rights reserved).

  1. Wolves (Canis lupus) and Dogs (Canis familiaris) Differ in Following Human Gaze Into Distant Space But Respond Similar to Their Packmates’ Gaze

    Science.gov (United States)

    Werhahn, Geraldine; Virányi, Zsófia; Barrera, Gabriela; Sommese, Andrea; Range, Friederike

    2017-01-01

    Gaze following into distant space is defined as visual co-orientation with another individual’s head direction allowing the gaze follower to gain information on its environment. Human and nonhuman animals share this basic gaze following behavior, suggested to rely on a simple reflexive mechanism and believed to be an important prerequisite for complex forms of social cognition. Pet dogs differ from other species in that they follow only communicative human gaze clearly addressed to them. However, in an earlier experiment we showed that wolves follow human gaze into distant space. Here we set out to investigate whether domestication has affected gaze following in dogs by comparing pack-living dogs and wolves raised and kept under the same conditions. In Study 1 we found that in contrast to the wolves, these dogs did not follow minimally communicative human gaze into distant space in the same test paradigm. In the observational Study 2 we found that pack-living dogs and wolves, similarly vigilant to environmental stimuli, follow the spontaneous gaze of their conspecifics similarly often. Our findings suggest that domestication did not affect the gaze following ability of dogs itself. The results raise hypotheses about which other dog skills might have been altered through domestication that may have influenced their performance in Study 1. Because following human gaze in dogs might be influenced by special evolutionary as well as developmental adaptations to interactions with humans, we suggest that comparing dogs to other animal species might be more informative when done in intraspecific social contexts. PMID:27244538

  2. Sustainability and the anthropogenic alteration of evolutionary processes

    Directory of Open Access Journals (Sweden)

    John Cairns, Jr.

    2004-08-01

    Full Text Available Persuasive evidence indicates that Earth is now experiencing a major biotic crisis. Even if humankind ceases severe stress on natural systems, the crisis will probably disrupt the basic evolutionary processes that characterized the period preceding the agricultural and industrial revolutions.Proliferation of drug and pesticide resistant species and opportunistic species that thrive in human-dominated ecosystems will become increasingly common. The effect on humankind of altering basic evolutionary processes is uncertain because the understanding of these processes is not robust. The probable result will not be an environment as favorable to humans as the one that has existed for most of human history. Humans probably have altered the environment since Homo sapiens first appeared. However, only in the last two centuries has the degree and rate of change reached levels now considered by many people to be ‘normal’, even though the record shows they are not.Greatly improved technology has facilitated increased exploitation of natural resources to unsustainablelevels. This exploitation, in turn, has led to exponential human population growth, which has depleted natural capital (living systems and the services they provide. Economic globalization has ensured that ecosystems far distant from consumers can be and are profitably exploited. Economicgrowth has become a universal mantra that is coupled with a conviction that such growth can continue indefinitely on a finite planet. A major paradigm shift is essential if sustainable use of the planet is to become a reality.

  3. Impact of transcriptional properties on essentiality and evolutionary rate.

    Science.gov (United States)

    Choi, Jung Kyoon; Kim, Sang Cheol; Seo, Jungmin; Kim, Sangsoo; Bhak, Jong

    2007-01-01

    We characterized general transcriptional activity and variability of eukaryotic genes from global expression profiles of human, mouse, rat, fly, plants, and yeast. The variability shows a higher degree of divergence between distant species, implying that it is more closely related to phenotypic evolution, than the activity. More specifically, we show that transcriptional variability should be a true indicator of evolutionary rate. If we rule out the effect of translational selection, which seems to operate only in yeast, the apparent slow evolution of highly expressed genes should be attributed to their low variability. Meanwhile, rapidly evolving genes may acquire a high level of transcriptional variability and contribute to phenotypic variations. Essentiality also seems to be correlated with the variability, not the activity. We show that indispensable or highly interactive proteins tend to be present in high abundance to maintain a low variability. Our results challenge the current theory that highly expressed genes are essential and evolve slowly. Transcriptional variability, rather than transcriptional activity, might be a common indicator of essentiality and evolutionary rate, contributing to the correlation between the two variables.

  4. Evolutionary foundations for cancer biology.

    Science.gov (United States)

    Aktipis, C Athena; Nesse, Randolph M

    2013-01-01

    New applications of evolutionary biology are transforming our understanding of cancer. The articles in this special issue provide many specific examples, such as microorganisms inducing cancers, the significance of within-tumor heterogeneity, and the possibility that lower dose chemotherapy may sometimes promote longer survival. Underlying these specific advances is a large-scale transformation, as cancer research incorporates evolutionary methods into its toolkit, and asks new evolutionary questions about why we are vulnerable to cancer. Evolution explains why cancer exists at all, how neoplasms grow, why cancer is remarkably rare, and why it occurs despite powerful cancer suppression mechanisms. Cancer exists because of somatic selection; mutations in somatic cells result in some dividing faster than others, in some cases generating neoplasms. Neoplasms grow, or do not, in complex cellular ecosystems. Cancer is relatively rare because of natural selection; our genomes were derived disproportionally from individuals with effective mechanisms for suppressing cancer. Cancer occurs nonetheless for the same six evolutionary reasons that explain why we remain vulnerable to other diseases. These four principles-cancers evolve by somatic selection, neoplasms grow in complex ecosystems, natural selection has shaped powerful cancer defenses, and the limitations of those defenses have evolutionary explanations-provide a foundation for understanding, preventing, and treating cancer.

  5. The major synthetic evolutionary transitions.

    Science.gov (United States)

    Solé, Ricard

    2016-08-19

    Evolution is marked by well-defined events involving profound innovations that are known as 'major evolutionary transitions'. They involve the integration of autonomous elements into a new, higher-level organization whereby the former isolated units interact in novel ways, losing their original autonomy. All major transitions, which include the origin of life, cells, multicellular systems, societies or language (among other examples), took place millions of years ago. Are these transitions unique, rare events? Have they instead universal traits that make them almost inevitable when the right pieces are in place? Are there general laws of evolutionary innovation? In order to approach this problem under a novel perspective, we argue that a parallel class of evolutionary transitions can be explored involving the use of artificial evolutionary experiments where alternative paths to innovation can be explored. These 'synthetic' transitions include, for example, the artificial evolution of multicellular systems or the emergence of language in evolved communicating robots. These alternative scenarios could help us to understand the underlying laws that predate the rise of major innovations and the possibility for general laws of evolved complexity. Several key examples and theoretical approaches are summarized and future challenges are outlined.This article is part of the themed issue 'The major synthetic evolutionary transitions'. © 2016 The Author(s).

  6. Structural symmetry in evolutionary games

    Science.gov (United States)

    McAvoy, Alex; Hauert, Christoph

    2015-01-01

    In evolutionary game theory, an important measure of a mutant trait (strategy) is its ability to invade and take over an otherwise-monomorphic population. Typically, one quantifies the success of a mutant strategy via the probability that a randomly occurring mutant will fixate in the population. However, in a structured population, this fixation probability may depend on where the mutant arises. Moreover, the fixation probability is just one quantity by which one can measure the success of a mutant; fixation time, for instance, is another. We define a notion of homogeneity for evolutionary games that captures what it means for two single-mutant states, i.e. two configurations of a single mutant in an otherwise-monomorphic population, to be ‘evolutionarily equivalent’ in the sense that all measures of evolutionary success are the same for both configurations. Using asymmetric games, we argue that the term ‘homogeneous’ should apply to the evolutionary process as a whole rather than to just the population structure. For evolutionary matrix games in graph-structured populations, we give precise conditions under which the resulting process is homogeneous. Finally, we show that asymmetric matrix games can be reduced to symmetric games if the population structure possesses a sufficient degree of symmetry. PMID:26423436

  7. Evolutionary genomics of environmental pollution.

    Science.gov (United States)

    Whitehead, Andrew

    2014-01-01

    Chemical toxins have been a persistent source of evolutionary challenges throughout the history of life, and deep within the genomic storehouse of evolutionary history lay ancient adaptations to diverse chemical poisons. However, the rate of change of contemporary environments mediated by human-introduced pollutants is rapidly screening this storehouse and severely testing the adaptive potential of many species. In this chapter, we briefly review the deep history of evolutionary adaptation to environmental toxins, and then proceed to describe the attributes of stressors and populations that may facilitate contemporary adaptation to pollutants introduced by humans. We highlight that phenotypes derived to enable persistence in polluted habitats may be multi-dimensional, requiring global genome-scale tools and approaches to uncover their mechanistic basis, and include examples of recent progress in the field. The modern tools of genomics offer promise for discovering how pollutants interact with genomes on physiological timescales, and also for discovering what genomic attributes of populations may enable resistance to pollutants over evolutionary timescales. Through integration of these sophisticated genomics tools and approaches with an understanding of the deep historical forces that shaped current populations, a more mature understanding of the mechanistic basis of contemporary ecological-evolutionary dynamics should emerge.

  8. Europe's space telescope ISO finds water in distant places

    Science.gov (United States)

    1997-04-01

    really is, in the words of an English poet, "Water, water everywhere". A Spanish astronomer, Jose Cernicharo of the Instituto de Estructura de la Materia in Madrid, has played a prominent part in this work. He is delighted by the results. "For the first time, we have a clear impression of the abundance of water in the Galaxy," Cernicharo says. "In relatively dense clouds as many as ten per cent of all oxygen atoms are incorporated into molecules of water vapour. Even more may be in the form of water ice. Water vapour is, after molecular hydrogen and carbon monoxide, one of the most important molecules in space. It plays an important role in the dynamical evolution of the gas inside the molecular clouds of our Galaxy, and hence in the formation of new stars." The water supply of the outer planets The water vapour in Saturn, Uranus and Neptune showed up in analyses of very accurate observations made with ISO's Short Wavelength Spectrometer during October and November 1996. A report to the world's astronomical community tells of a particularly clear water signature from Uranus, in distinctive infrared emissions at eight wavelengths between 28.43 and 44.19 microns. A preliminary analysis indicated that the water vapour exists in the giant planet's outer atmosphere, at a temperature around 0 degrees C. ISO detected six of the same water "lines" in the infrared spectrum of distant Neptune, and three in Saturn, which is closer than Uranus. The puzzle for planetary astronomers is now to figure out where the water comes from. These giant planets are a long way from the Sun. Uranus, for example, is twenty times farther out than the Earth is, and sunlight is feebler by a factor of 400. The planets have their own internal sources of heat, and they are thought to contain plenty of water incorporated when the planets formed. But it would be difficult for water vapour to escape into the outer atmosphere. On the other hand, water in the form of ice is a major constituent of comets

  9. Towards consistent mapping of distant worlds: secondary-eclipse scanning of the exoplanet HD 189733b

    Science.gov (United States)

    de Wit, J.; Gillon, M.; Demory, B.-O.; Seager, S.

    2012-12-01

    Context. Mapping distant worlds is the next frontier for exoplanet infrared (IR) photometry studies. Ultimately, constraining spatial and temporal properties of an exoplanet atmosphere (e.g., its temperature) will provide further insight into its physics. For tidally-locked hot Jupiters that transit and are eclipsed by their host star, the first steps are now possible. Aims: Our aim is to constrain an exoplanet's (1) shape, (2) brightness distribution (BD) and (3) system parameters from its phase curve and eclipse measurements. In particular, we rely on the secondary-eclipse scanning which is obtained while an exoplanet is gradually masked by its host star. Methods: We use archived Spitzer/IRAC 8-μm data of HD 189733 (six transits, eight secondary eclipses, and a phase curve) in a global Markov chain Monte Carlo (MCMC) procedure for mitigating systematics. We also include HD 189733's out-of-transit radial velocity (RV) measurements to assess their incidence on the inferences obtained solely from the photometry. Results: We find a 6σ deviation from the expected occultation of a uniformly-bright disk. This deviation emerges mainly from a large-scale hot spot in HD 189733b's atmosphere, not from HD 189733b's shape. We indicate that the correlation of the exoplanet orbital eccentricity, e, and BD ("uniform time offset") does also depend on the stellar density, ρ⋆, and the exoplanet impact parameter, b ("e-b-ρ⋆-BD correlation"). For HD 189733b, we find that relaxing the eccentricity constraint and using more complex BDs lead to lower stellar/planetary densities and a more localized and latitudinally-shifted hot spot. We, therefore, show that the light curve of an exoplanet does not constrain uniquely its brightness peak localization. Finally, we obtain an improved constraint on the upper limit of HD 189733b's orbital eccentricity, e ≤ 0.011 (95% confidence), when including HD 189733's RV measurements. Conclusions: Reanalysis of archived HD 189733's data

  10. Neuronal boost to evolutionary dynamics.

    Science.gov (United States)

    de Vladar, Harold P; Szathmáry, Eörs

    2015-12-06

    Standard evolutionary dynamics is limited by the constraints of the genetic system. A central message of evolutionary neurodynamics is that evolutionary dynamics in the brain can happen in a neuronal niche in real time, despite the fact that neurons do not reproduce. We show that Hebbian learning and structural synaptic plasticity broaden the capacity for informational replication and guided variability provided a neuronally plausible mechanism of replication is in place. The synergy between learning and selection is more efficient than the equivalent search by mutation selection. We also consider asymmetric landscapes and show that the learning weights become correlated with the fitness gradient. That is, the neuronal complexes learn the local properties of the fitness landscape, resulting in the generation of variability directed towards the direction of fitness increase, as if mutations in a genetic pool were drawn such that they would increase reproductive success. Evolution might thus be more efficient within evolved brains than among organisms out in the wild.

  11. Evolutionary psychology and intelligence research.

    Science.gov (United States)

    Kanazawa, Satoshi

    2010-01-01

    This article seeks to unify two subfields of psychology that have hitherto stood separately: evolutionary psychology and intelligence research/differential psychology. I suggest that general intelligence may simultaneously be an evolved adaptation and an individual-difference variable. Tooby and Cosmides's (1990a) notion of random quantitative variation on a monomorphic design allows us to incorporate heritable individual differences in evolved adaptations. The Savanna-IQ Interaction Hypothesis, which is one consequence of the integration of evolutionary psychology and intelligence research, can potentially explain why less intelligent individuals enjoy TV more, why liberals are more intelligent than conservatives, and why night owls are more intelligent than morning larks, among many other findings. The general approach proposed here will allow us to integrate evolutionary psychology with any other aspect of differential psychology. Copyright 2010 APA, all rights reserved.

  12. Predictive factors for loco regional recurrence and distant metastasis following primary surgical treatment of cutaneous melanoma

    Directory of Open Access Journals (Sweden)

    Vijayalakshmi Deshmane

    2014-01-01

    Full Text Available Background: Cutaneous melanoma (CM has a high propensity for regional and systemic spread. This is one of the largest series of CM reported from India. Aims: To predict factors for loco regional recurrence (LRR and distant metastasis in patients with CM primarily treated with surgery. Study Design: Retrospective analysis of patient database at a tertiary care cancer center with evaluation of factors for LRR and distant metastasis for CM. Materials and Methods: Data from 68 patients treated for CM between January 2006 and December 2010 were reviewed. Data recorded included age, sex, symptoms, investigations, treatment given, histopathology, recurrence and follow-up. Patient factors, tumor factors, pathologic variables, and adjuvant treatment were investigated as predictors′ of LRR and distant metastasis. Results: Mean age of patients was 54 years. Melanoma was more common in males (44. Tumor thickness > 4 mm was found in 43 patients. Lymph node involvement was found in 43 patients. Adjuvant radiotherapy was given in seven patients. At mean follow-up of 16.5 months, LRR was seen in 34 patients and distant metastasis in 28 patients. LRR and distant metastasis were more commonly found in females, age > 40 years, Clark′s level IV and V, Breslow′s depth > 4 mm, patients with lymph node involvement and extra-capsular spread. Conclusion: The age, sex, site, thickness of lesion, involvement of lymph node, and extra-capsular spread were important factors in predicting LRR and distant metastasis. Distant metastasis was also more commonly found in patients with LRR.

  13. Genes from scratch – the evolutionary fate of de novo genes

    Science.gov (United States)

    Schlötterer, Christian

    2015-01-01

    Although considered an extremely unlikely event, many genes emerge from previously noncoding genomic regions. This review covers the entire life cycle of such de novo genes. Two competing hypotheses about the process of de novo gene birth are discussed as well as the high death rate of de novo genes. Despite the high death rate, some de novo genes are retained and remain functional, even in distantly related species, through their integration into gene networks. Further studies combining gene expression with ribosome profiling in multiple populations across different species will be instrumental for an improved understanding of the evolutionary processes operating on de novo genes. PMID:25773713

  14. Correlation analysis for protein evolutionary family based on amino acid position mutations and application in PDZ domain.

    Directory of Open Access Journals (Sweden)

    Qi-Shi Du

    Full Text Available BACKGROUND: It has been widely recognized that the mutations at specific directions are caused by the functional constraints in protein family and the directional mutations at certain positions control the evolutionary direction of the protein family. The mutations at different positions, even distantly separated, are mutually coupled and form an evolutionary network. Finding the controlling mutative positions and the mutative network among residues are firstly important for protein rational design and enzyme engineering. METHODOLOGY: A computational approach, namely amino acid position conservation-mutation correlation analysis (CMCA, is developed to predict mutually mutative positions and find the evolutionary network in protein family. The amino acid position mutative function, which is the foundational equation of CMCA measuring the mutation of a residue at a position, is derived from the MSA (multiple structure alignment database of protein evolutionary family. Then the position conservation correlation matrix and position mutation correlation matrix is constructed from the amino acid position mutative equation. Unlike traditional SCA (statistical coupling analysis approach, which is based on the statistical analysis of position conservations, the CMCA focuses on the correlation analysis of position mutations. CONCLUSIONS: As an example the CMCA approach is used to study the PDZ domain of protein family, and the results well illustrate the distantly allosteric mechanism in PDZ protein family, and find the functional mutative network among residues. We expect that the CMCA approach may find applications in protein engineering study, and suggest new strategy to improve bioactivities and physicochemical properties of enzymes.

  15. Diversity-Guided Evolutionary Algorithms

    DEFF Research Database (Denmark)

    Ursem, Rasmus Kjær

    2002-01-01

    Population diversity is undoubtably a key issue in the performance of evolutionary algorithms. A common hypothesis is that high diversity is important to avoid premature convergence and to escape local optima. Various diversity measures have been used to analyze algorithms, but so far few...... algorithms have used a measure to guide the search. The diversity-guided evolutionary algorithm (DGEA) uses the wellknown distance-to-average-point measure to alternate between phases of exploration (mutation) and phases of exploitation (recombination and selection). The DGEA showed remarkable results...

  16. Exponential Expansion in Evolutionary Economics

    DEFF Research Database (Denmark)

    Frederiksen, Peter; Jagtfelt, Tue

    2013-01-01

    of Thomas Kuhn’s notion of scientific paradigms and criteria for a good theory (1977, 1996). The paper thus aims to augment and assimilate the fragmented and scattered body of concepts presently residing within the field of evolutionary economics, by presenting an intuitive framework, applicable within...... concepts are described in detail. Taken together it provides the rudimentary aspects of an economic system within an analytical perspective. It is argued that the main dynamic processes of the evolutionary perspective can be reduced to these four concepts. The model and concepts are evaluated in the light...

  17. Evolutionary Aesthetics and Print Advertising

    Directory of Open Access Journals (Sweden)

    Kamil Luczaj

    2015-06-01

    Full Text Available The article analyzes the extent to which predictions based on the theory of evolutionary aesthetics are utilized by the advertising industry. The purpose of a comprehensive content analysis of print advertising is to determine whether the items indicated by evolutionists such as animals, flowers, certain types of landscapes, beautiful humans, and some colors are part of real advertising strategies. This article has shown that many evolutionary hypotheses (although not all of them are supported by empirical data. Along with these hypotheses, some inferences from Bourdieu’s cultural capital theory were tested. It turned out that advertising uses both biological schemata and cultural patterns to make an image more likable.

  18. The evolutionary psychology of violence.

    Science.gov (United States)

    Goetz, Aaron T

    2010-02-01

    This paper reviews theory and research on the evolutionary psychology of violence. First, I examine evidence suggesting that humans have experienced an evolutionary history of violence. Next, I discuss violence as a context-sensitive strategy that might have provided benefits to our ancestors under certain circumstances. I then focus on the two most common forms of violence that plague humans -violence over status contests and intimate partner violence- outlining psychological mechanisms involved in each. Finally, I suggest that greater progress will be made by shifting the study from contexts to mechanisms.

  19. The evolutionary psychology of hunger.

    Science.gov (United States)

    Al-Shawaf, Laith

    2016-10-01

    An evolutionary psychological perspective suggests that emotions can be understood as coordinating mechanisms whose job is to regulate various psychological and physiological programs in the service of solving an adaptive problem. This paper suggests that it may also be fruitful to approach hunger from this coordinating mechanism perspective. To this end, I put forward an evolutionary task analysis of hunger, generating novel a priori hypotheses about the coordinating effects of hunger on psychological processes such as perception, attention, categorization, and memory. This approach appears empirically fruitful in that it yields a bounty of testable new hypotheses. Copyright © 2016 Elsevier Ltd. All rights reserved.

  20. Evolutionary Dynamics of Biological Games

    Science.gov (United States)

    Nowak, Martin A.; Sigmund, Karl

    2004-02-01

    Darwinian dynamics based on mutation and selection form the core of mathematical models for adaptation and coevolution of biological populations. The evolutionary outcome is often not a fitness-maximizing equilibrium but can include oscillations and chaos. For studying frequency-dependent selection, game-theoretic arguments are more appropriate than optimization algorithms. Replicator and adaptive dynamics describe short- and long-term evolution in phenotype space and have found applications ranging from animal behavior and ecology to speciation, macroevolution, and human language. Evolutionary game theory is an essential component of a mathematical and computational approach to biology.

  1. Altered structural connectome in temporal lobe epilepsy.

    Science.gov (United States)

    DeSalvo, Matthew N; Douw, Linda; Tanaka, Naoaki; Reinsberger, Claus; Stufflebeam, Steven M

    2014-03-01

    To study differences in the whole-brain structural connectomes of patients with left temporal lobe epilepsy (TLE) and healthy control subjects. This study was approved by the institutional review board, and all individuals gave signed informed consent. Sixty-direction diffusion-tensor imaging and magnetization-prepared rapid acquisition gradient-echo (MP-RAGE) magnetic resonance imaging volumes were analyzed in 24 patients with left TLE and in 24 healthy control subjects. MP-RAGE volumes were segmented into 1015 regions of interest (ROIs) spanning the entire brain. Deterministic white matter tractography was performed after voxelwise tensor calculation. Weighted structural connectivity matrices were generated by using the pairwise density of connecting fibers between ROIs. Graph theoretical measures of connectivity networks were compared between groups by using linear models with permutation testing. Patients with TLE had 22%-45% reduced (P < .01) distant connectivity in the medial orbitofrontal cortex, temporal cortex, posterior cingulate cortex, and precuneus, compared with that in healthy subjects. However, local connectivity, as measured by means of network efficiency, was increased by 85%-270% (P < .01) in the medial and lateral frontal cortices, insular cortex, posterior cingulate cortex, precuneus, and occipital cortex in patients with TLE as compared with healthy subjects. This study suggests that TLE involves altered structural connectivity in a network that reaches beyond the temporal lobe, especially in the default mode network.

  2. Observational Bias and the Clustering of Distant Eccentric Kuiper Belt Objects

    Science.gov (United States)

    Brown, Michael E.

    2017-08-01

    The hypothesis that a massive Planet Nine exists in the outer solar system on a distant eccentric orbit was inspired by observations showing that the objects with the most distant eccentric orbits in the Kuiper Belt have orbits that are physically aligned, that is, they are clustered in longitude of perihelion and have similar orbital planes. Questions have remained, however, about the effects of observational bias on these observations, particularly on the longitudes of perihelion. Specifically, distant eccentric Kuiper Belt objects (KBOs) tend to be faint and only observable near their perihelia, suggesting that the longitudes of perihelion of the known distant objects could be strongly biased by the limited number of locations in the sky where deep surveys have been carried out. We have developed a method to rigorously estimate the bias in longitude of perihelion for Kuiper Belt observations. We find that the probability that the 10 known KBOs with semimajor axis beyond 230 au are drawn from a population with uniform longitude of perihelion is 1.2%. Combined with the observation that the orbital poles of these objects are also clustered, the overall probability of detecting these two independent clusterings in a randomly distributed sample is 0.025%. While observational bias is clearly present in these observations, it is unlikely to explain the observed alignment of the distant eccentric KBOs.

  3. Risk Factors for Distant Metastasis in Patients with Oral Cavity Squamous Cell Carcinoma Undergoing Surgical Treatment.

    Science.gov (United States)

    Aires, Felipe Toyama; Lin, Chin Shien; Matos, Leandro Luongo; Kulcsar, Marco Aurélio Vamondes; Cernea, Claudio Roberto

    2018-01-23

    The aim of this study is to investigate the clinical and pathological factors related to distant metastasis in patients with oral cavity squamous cell carcinoma (OCSCC) undergoing surgery. A retrospective data review was conducted on patients who underwent primary surgery for OCSCC at the Instituto do Cancer do Estado de São Paulo (ICESP) between 2009 and 2015. Distant metastasis rates were calculated and predictive factors were determined by the Cox proportional-hazards model. There was a total of 274 patients, including 210 (76.6%) men and 64 (23.4%) women, with a mean age of 59.9 ± 10.9 years. The incidence of distant metastasis was 9.6%, with the lung being the most common site. The mean time interval between surgical treatment and the diagnosis of distant metastasis was 12 months (range 2-40 months). In the multivariate analysis, angiolymphatic invasion (HR = 2,87; p = 0.023), contralateral cervical metastasis (HR = 3.3; p = 0,007), tumor thickness >25 mm (HR = 3.50; p = 0.009), and locoregional recurrence (HR = 6.59; p 25 mm, angiolymphatic invasion, or locoregional recurrence after surgical treatment have a greater risk of developing distant metastasis. © 2018 S. Karger AG, Basel.

  4. Effects of Distant Green Space on Physical Activity in Sydney, Australia.

    Science.gov (United States)

    Chong, Shanley; Byun, Roy; Mazumdar, Soumya; Bauman, Adrian; Jalaludin, Bin

    2017-01-01

    The aim was to investigate the association between distant green space and physical activity modified by local green space. Information about physical activity, demographic and socioeconomic background at the individual level was extracted from the New South Wales Population Health Survey. The proportion of a postcode that was parkland was used as a proxy measure for access to parklands and was calculated for each individual. There was a significant relationship between distant green space and engaging in moderate-to-vigorous physical activity (MVPA) at least once a week. No significant relationship was found between adequate physical activity and distant green space. No significant relationships were found between adequate physical activity, engaging in MVPA, and local green space. However, if respondents lived in greater local green space (≥25%), there was a significant relationship between engaging in MVPA at least once a week and distance green space of ≥20%. This study highlights the important effect of distant green space on physical activity. Our findings also suggest that moderate size of local green space together with moderate size of distant green space are important levers for participation of physical activity.

  5. Distinguishing synchronous from metachronous manifestation of distant metastases: a prognostic feature in differentiated thyroid carcinoma.

    Science.gov (United States)

    Sabet, Amir; Binse, Ina; Dogan, Semih; Koch, Andrea; Rosenbaum-Krumme, Sandra J; Biersack, Hans-Jürgen; Biermann, Kim; Ezziddin, Samer

    2017-02-01

    Distant metastasis has a negative impact on survival in differentiated thyroid carcinoma (DTC). The timing of this manifestation, however, is of unknown prognostic relevance. The aim of this retrospective study was to investigate the potential significance of discriminating synchronous versus metachronous distant metastases (SDM vs. MDM) for the outcome of patients with DTC. We retrospectively analyzed a consecutive cohort of n = 89 patients with distant metastases of DTC (43 with follicular, 46 with papillary DTC histology; mean age 52.6 ± 17.7 years) undergoing radioiodine treatment at our institution. All patients were treated with the same protocol consisting of ablative radioiodine therapy (RIT, 3.7 GBq) and one post-ablation treatment after 3 months (3.7-11.1 GBq). Further cycles of RIT were administered for recurrent, progressive or newly developed metastatic disease. We distinguished 2 types of distant metastases according to the time of manifestation: SDM (within ≤12 months after DTC diagnosis) and MDM (occurring >12 months after diagnosis). Tumor-related survival was analyzed using the Kaplan-Meier method. Uni- and multivariate analyses including the Cox proportional hazards model were performed with a significance level of p manifestation of distant metastases may add an important prognostic feature to risk stratification in DTC, as proven metachronous appearance is associated with impaired survival.

  6. Can Platelet and Leukocyte Indicators Give Us an Idea about Distant Metastasis in Nasopharyngeal Cancer?

    Science.gov (United States)

    Arıcıgil, Mitat; Dündar, Mehmet Akif; Yücel, Abitter; Arbağ, Hamdi; Aziz, Suhayb Kuria

    This study aimes to evaluate platelet and leucocyte indicators, such as the mean platelet volume, platelet distribution width, plateletcrit, white blood cell count, neutrophil to lymphocyte ratio in nasopharyngeal cancer patients and also to evaluate the relationship between these indicators and nasopharyngeal cancer with distant metastasis. The medical records of 118 patients diagnosed with nasopharyngeal cancer in our hospital between January 2006 and August 2015 were reviewed. The nasopharyngeal cancer group was further sub grouped according to the presence or absence of distant metastasis and TNM (tumour - T, node - N, metastasis - M) classification. A control group consisted of 120 healthy patients. The platelet and leucocyte values at the time of the initial diagnosis were recorded. Neutrophil to lymphocyte ratio and platelet distribution width values were significantly higher in the nasopharyngeal cancer group. But only platelet distribution width values were significantly higher in the nasopharyngeal cancer group with distant metastasis compared to the nasopharyngeal cancer group without distant metastasis. Neutrophil to lymphocyte ratio and platelet distribution width values may increase in nasopharyngeal cancer. But only the platelet distribution width values may give us an idea about the distant metastasis in nasopharyngeal cancer.

  7. Probing the evolutionary history of epigenetic mechanisms: what can we learn from marine diatoms

    Directory of Open Access Journals (Sweden)

    Achal Rastogi

    2015-07-01

    Full Text Available Recent progress made on epigenetic studies revealed the conservation of epigenetic features in deep diverse branching species including Stramenopiles, plants and animals. This suggests their fundamental role in shaping species genomes across different evolutionary time scales. Diatoms are a highly successful and diverse group of phytoplankton with a fossil record of about 190 million years ago. They are distantly related from other super-groups of Eukaryotes and have retained some of the epigenetic features found in mammals and plants suggesting their ancient origin. Phaeodactylum tricornutum and Thalassiosira pseudonana, pennate and centric diatoms, respectively, emerged as model species to address questions on the evolution of epigenetic phenomena such as what has been lost, retained or has evolved in contemporary species. In the present work, we will discuss how the study of non-model or emerging model organisms, such as diatoms, helps understand the evolutionary history of epigenetic mechanisms with a particular focus on DNA methylation and histone modifications.

  8. Evolutionary robotics – A review

    Indian Academy of Sciences (India)

    R. Narasimhan (Krishtel eMaging) 1461 1996 Oct 15 13:05:22

    MS received 26 June 2001; revised 9 May 2003. Abstract. In evolutionary robotics, a suitable robot control system is developed automatically through evolution due to the interactions between the robot and its environment. It is a complicated task, as the robot and the environment constitute a highly dynamical system.

  9. Evolutionary genetics: the Drosophila model

    Indian Academy of Sciences (India)

    Unknown

    Evolutionary genetics straddles the two fundamental processes of life, development (the transition from egg to adult) and reproduction (the generation of eggs from adults), and scrutinizes, from an evolu- tionary perspective, the nature .... script profiles in aging and calorically restricted Drosophila melanogaster. Curr. Biol.

  10. Current Issues in Evolutionary Paleontology.

    Science.gov (United States)

    Scully, Erik Paul

    1987-01-01

    Describes some of the contributions made by the field of paleontology to theories in geology and biology. Suggests that the two best examples of modern evolutionary paleontology relate to the theory of punctuated equilibria, and the possibility that mass extinctions may be cyclic. (TW)

  11. Conceptual foundations of evolutionary thought

    Indian Academy of Sciences (India)

    2017-07-04

    Jul 4, 2017 ... Home; Journals; Journal of Genetics; Volume 96; Issue 3. Conceptual foundations of evolutionary thought. K. P. MOHANAN. Perspectives Volume 96 Issue 3 July 2017 pp 401-412. Fulltext. Click here to view fulltext PDF. Permanent link: http://www.ias.ac.in/article/fulltext/jgen/096/03/0401-0412. Abstract ...

  12. Evolutionary Biology Research in India

    Indian Academy of Sciences (India)

    Home; Journals; Resonance – Journal of Science Education; Volume 5; Issue 10. Evolutionary Biology Research in India. Information and Announcements Volume 5 Issue 10 October 2000 pp 102-104. Fulltext. Click here to view fulltext PDF. Permanent link: http://www.ias.ac.in/article/fulltext/reso/005/10/0102-0104 ...

  13. Haldane and modern evolutionary genetics

    Indian Academy of Sciences (India)

    Home; Journals; Journal of Genetics; Volume 96; Issue 5. Haldane and modern evolutionary genetics. BRIAN CHARLESWORTH. HALDANE AT 125 Volume 96 Issue 5 November 2017 pp 773-782. Fulltext. Click here to view fulltext PDF. Permanent link: http://www.ias.ac.in/article/fulltext/jgen/096/05/0773-0782. Keywords.

  14. Evolutionary trends in directional hearing

    DEFF Research Database (Denmark)

    Carr, Catherine E; Christensen-Dalsgaard, Jakob

    2016-01-01

    Tympanic hearing is a true evolutionary novelty that arose in parallel within early tetrapods. We propose that in these tetrapods, selection for sound localization in air acted upon pre-existing directionally sensitive brainstem circuits, similar to those in fishes. Auditory circuits in birds...

  15. Is evolutionary biology strategic science?

    Science.gov (United States)

    Meagher, Thomas R

    2007-01-01

    There is a profound need for the scientific community to be better aware of the policy context in which it operates. To address this need, Evolution has established a new Outlook feature section to include papers that explore the interface between society and evolutionary biology. This first paper in the series considers the strategic relevance of evolutionary biology. Support for scientific research in general is based on governmental or institutional expenditure that is an investment, and such investment is based on strategies designed to achieve particular outcomes, such as advance in particular areas of basic science or application. The scientific community can engage in the development of scientific strategies on a variety of levels, including workshops to explicitly develop research priorities and targeted funding initiatives to help define emerging scientific areas. Better understanding and communication of the scientific achievements of evolutionary biology, emphasizing immediate and potential societal relevance, are effective counters to challenges presented by the creationist agenda. Future papers in the Outlook feature section should assist the evolutionary biology community in achieving a better collective understanding of the societal relevance of their field.

  16. The Evolutionary Ecology of Mutualism

    NARCIS (Netherlands)

    Ivens, A.B.F.

    2012-01-01

    Mutualism, cooperation between different species, is wide-spread in nature. From bees pollinating plants to bacteria aiding digestion in the human gut: mutualism is essential for life on earth. But how does mutualism evolve? And what mechanisms keep mutualisms stable over evolutionary time and

  17. Evolutionary dynamics of mammalian karyotypes

    Directory of Open Access Journals (Sweden)

    Carlo Alberto Redi

    2012-12-01

    Full Text Available This special volume of Cytogenetic and Genome Research (edited by Roscoe Stanyon, University of Florence and Alexander Graphodatsky, Siberian division of the Russian Academy of Sciences is dedicated to the fascinating long search of the forces behind the evolutionary dynamics of mammalian karyotypes, revealed after the hypotonic miracle of the 1950s....

  18. Euryhalinity in an evolutionary context

    Science.gov (United States)

    Schultz, Eric T.; McCormick, Stephen D.; McCormick, Stephen D.; Farrell, Anthony Peter; Brauner, Colin J.

    2013-01-01

    This chapter focuses on the evolutionary importance and taxonomic distribution of euryhalinity. Euryhalinity refers to broad halotolerance and broad halohabitat distribution. Salinity exposure experiments have demonstrated that species vary tenfold in their range of tolerable salinity levels, primarily because of differences in upper limits. Halotolerance breadth varies with the species’ evolutionary history, as represented by its ordinal classification, and with the species’ halohabitat. Freshwater and seawater species tolerate brackish water; their empirically-determined fundamental haloniche is broader than their realized haloniche, as revealed by the halohabitats they occupy. With respect to halohabitat distribution, a minority of species (<10%) are euryhaline. Habitat-euryhalinity is prevalent among basal actinopterygian fishes, is largely absent from orders arising from intermediate nodes, and reappears in the most derived taxa. There is pronounced family-level variability in the tendency to be halohabitat-euryhaline, which may have arisen during a burst of diversification following the Cretaceous-Palaeogene extinction. Low prevalence notwithstanding, euryhaline species are potent sources of evolutionary diversity. Euryhalinity is regarded as a key innovation trait whose evolution enables exploitation of new adaptive zone, triggering cladogenesis. We review phylogenetically-informed studies that demonstrate freshwater species diversifying from euryhaline ancestors through processes such as landlocking. These studies indicate that some euryhaline taxa are particularly susceptible to changes in halohabitat and subsequent diversification, and some geographic regions have been hotspots for transitions to freshwater. Comparative studies on mechanisms among multiple taxa and at multiple levels of biological integration are needed to clarify evolutionary pathways to, and from, euryhalinity.

  19. Realism, Relativism, and Evolutionary Psychology

    NARCIS (Netherlands)

    Derksen, M.

    Against recent attempts to forge a reconciliation between constructionism and realism, I contend that, in psychology at least, stirring up conflict is a more fruitful strategy. To illustrate this thesis, I confront a school of psychology with strong realist leanings, evolutionary psychology, with

  20. Evolutionary Psychology and Intelligence Research

    Science.gov (United States)

    Kanazawa, Satoshi

    2010-01-01

    This article seeks to unify two subfields of psychology that have hitherto stood separately: evolutionary psychology and intelligence research/differential psychology. I suggest that general intelligence may simultaneously be an evolved adaptation and an individual-difference variable. Tooby and Cosmides's (1990a) notion of random quantitative…

  1. Major evolutionary transitions in individuality

    NARCIS (Netherlands)

    West, S.A.; Fisher, R.M.; Gardner, A.; Kiers, E.T.

    2015-01-01

    The evolution of life on earth has been driven by a small number of major evolutionary transitions. These transitions have been characterized by individuals that could previously replicate independently, cooperating to form a new, more complex life form. For example, archaea and eubacteria formed

  2. Comparative Profiling of miRNAs and Target Gene Identification in Distant-Grafting between Tomato andLycium(Goji Berry).

    Science.gov (United States)

    Khaldun, A B M; Huang, Wenjun; Lv, Haiyan; Liao, Sihong; Zeng, Shaohua; Wang, Ying

    2016-01-01

    Local translocation of small RNAs between cells is proved. Long distance translocation between rootstock and scion is also well documented in the homo-grafting system, but the process in distant-grafting is widely unexplored where rootstock and scion belonging to different genera. Micro RNAs are a class of small, endogenous, noncoding, gene silencing RNAs that regulate target genes of a wide range of important biological pathways in plants. In this study, tomato was grafted onto goji ( Lycium chinense Mill.) to reveal the insight of miRNAs regulation and expression patterns within a distant-grafting system. Goji is an important traditional Chinese medicinal plant with enriched phytochemicals. Illumina sequencing technology has identified 68 evolutionary known miRNAs of 37 miRNA families. Moreover, 168 putative novel miRNAs were also identified. Compared with control tomato, 43 (11 known and 32 novels) and 163 (33 known and 130 novels) miRNAs were expressed significantly different in shoot and fruit of grafted tomato, respectively. The fruiting stage was identified as the most responsive in the distant-grafting approach and 123 miRNAs were found as up-regulating in the grafted fruit which is remarkably higher compare to the grafted shoot tip (28). Potential targets of differentially expressed miRNAs were found to be involved in diverse metabolic and regulatory pathways. ADP binding activities, molybdopterin synthase complex and RNA helicase activity were found as enriched terms in GO (Gene Ontology) analysis. Additionally, "metabolic pathways" was revealed as the most significant pathway in KEGG (Kyoto Encyclopedia of Genes and Genomes) analysis. The information of the small RNA transcriptomes that are obtained from this study might be the first miRNAs elucidation for a distant-grafting system, particularly between goji and tomato. The results from this study will provide the insights into the molecular aspects of miRNA-mediated regulation in the medicinal plant

  3. "Wolves (Canis lupus) and dogs (Canis familiaris) differ in following human gaze into distant space but respond similar to their packmates' gaze": Correction to Werhahn et al. (2016).

    Science.gov (United States)

    2017-02-01

    Reports an error in "Wolves ( Canis lupus ) and dogs ( Canis familiaris ) differ in following human gaze into distant space but respond similar to their packmates' gaze" by Geraldine Werhahn, Zsófia Virányi, Gabriela Barrera, Andrea Sommese and Friederike Range ( Journal of Comparative Psychology , 2016[Aug], Vol 130[3], 288-298). In the article, the affiliations for the second and fifth authors should be Wolf Science Center, Ernstbrunn, Austria, and Comparative Cognition, Messerli Research Institute, University of Veterinary Medicine Vienna/ Medical University of Vienna/University of Vienna. The online version of this article has been corrected. (The following abstract of the original article appeared in record 2016-26311-001.) Gaze following into distant space is defined as visual co-orientation with another individual's head direction allowing the gaze follower to gain information on its environment. Human and nonhuman animals share this basic gaze following behavior, suggested to rely on a simple reflexive mechanism and believed to be an important prerequisite for complex forms of social cognition. Pet dogs differ from other species in that they follow only communicative human gaze clearly addressed to them. However, in an earlier experiment we showed that wolves follow human gaze into distant space. Here we set out to investigate whether domestication has affected gaze following in dogs by comparing pack-living dogs and wolves raised and kept under the same conditions. In Study 1 we found that in contrast to the wolves, these dogs did not follow minimally communicative human gaze into distant space in the same test paradigm. In the observational Study 2 we found that pack-living dogs and wolves, similarly vigilant to environmental stimuli, follow the spontaneous gaze of their conspecifics similarly often. Our findings suggest that domestication did not affect the gaze following ability of dogs itself. The results raise hypotheses about which other dog skills

  4. Evolutionary biology of bacterial and fungal pathogens

    National Research Council Canada - National Science Library

    Baquero, F

    2008-01-01

    ... and Evolutionary Dynamics of Pathogens * 21 Keith A. Crandall and Marcos Pérez-Losada II. Evolutionary Genetics of Microbial Pathogens 4. Environmental and Social Influences on Infectious Disea...

  5. Towards a mechanistic foundation of evolutionary theory.

    Science.gov (United States)

    Doebeli, Michael; Ispolatov, Yaroslav; Simon, Burt

    2017-02-15

    Most evolutionary thinking is based on the notion of fitness and related ideas such as fitness landscapes and evolutionary optima. Nevertheless, it is often unclear what fitness actually is, and its meaning often depends on the context. Here we argue that fitness should not be a basal ingredient in verbal or mathematical descriptions of evolution. Instead, we propose that evolutionary birth-death processes, in which individuals give birth and die at ever-changing rates, should be the basis of evolutionary theory, because such processes capture the fundamental events that generate evolutionary dynamics. In evolutionary birth-death processes, fitness is at best a derived quantity, and owing to the potential complexity of such processes, there is no guarantee that there is a simple scalar, such as fitness, that would describe long-term evolutionary outcomes. We discuss how evolutionary birth-death processes can provide useful perspectives on a number of central issues in evolution.

  6. Dobzhansky and Evolutionary Cytogenetics-Pioneering ...

    Indian Academy of Sciences (India)

    Home; Journals; Resonance – Journal of Science Education; Volume 5; Issue 10. Dobzhansky and Evolutionary Cytogenetics - Pioneering Evolutionary Studies with Chromosomes. Bimalendu B Nath. General Article Volume 5 Issue 10 October 2000 pp 61-65 ...

  7. A method of real-time detection for distant moving obstacles by monocular vision

    Science.gov (United States)

    Jia, Bao-zhi; Zhu, Ming

    2013-12-01

    In this paper, we propose an approach for detection of distant moving obstacles like cars and bicycles by a monocular camera to cooperate with ultrasonic sensors in low-cost condition. We are aiming at detecting distant obstacles that move toward our autonomous navigation car in order to give alarm and keep away from them. Method of frame differencing is applied to find obstacles after compensation of camera's ego-motion. Meanwhile, each obstacle is separated from others in an independent area and given a confidence level to indicate whether it is coming closer. The results on an open dataset and our own autonomous navigation car have proved that the method is effective for detection of distant moving obstacles in real-time.

  8. Age at diagnosis and distant metastasis in breast cancer--a surprising inverse relationship.

    Science.gov (United States)

    Purushotham, A; Shamil, E; Cariati, M; Agbaje, O; Muhidin, A; Gillett, C; Mera, A; Sivanadiyan, K; Harries, M; Sullivan, R; Pinder, S E; Garmo, H; Holmberg, L

    2014-07-01

    Predictors for site of distant metastasis and impact on survival in breast cancer are incompletely understood. Clinico-pathological risk factors for site of distant metastasis and survival were analysed in patients with invasive breast cancer treated between 1986 and 2006. Of 3553 patients, with median follow-up 6.32years, 825 (23%) developed distant metastasis. The site of metastasis was bone in 196/825 (24%), viscera in 540/825 (65%) and unknown in 89 (11%). Larger primary invasive tumour size, higher tumour grade and axillary nodal positivity increased risk of metastasis to all sites. Lobular carcinoma was more likely to first metastasise to bone compared to invasive ductal carcinoma (NST). Oestrogen receptor (ER) negative, progesterone receptor (PgR) negative and/or Human epidermal growth factor (HER2) positive tumours were more likely to metastasise to viscera. A striking relationship between increasing age at diagnosis and a reduction in risk of distant metastasis to bone and viscera was observed. Median time to death from onset of metastatic disease was 1.52 (Interquartile range (IQR) 0.7-2.9)years for patients with bone metastasis and 0.7 (IQR 0.2-1.5)years for visceral metastasis. On multivariate analysis, despite the decrease in risk of distant metastasis with increasing age, there was an elevated hazard for death in patients >50years at diagnosis of metastasis if they developed bone metastasis, with a similar trend observed in the >70years age group if they developed visceral metastasis. These findings indicate that there are biological mechanisms underlying the impact of age on the development of distant metastasis and subsequent death. This may have important implications in the treatment of breast cancer. Copyright © 2014 Elsevier Ltd. All rights reserved.

  9. CD24 expression predicts distant metastasis in extrahepatic bile duct cancer

    Science.gov (United States)

    Kim, Kyubo; Min, Hye Sook; Chie, Eui Kyu; Jang, Jin-Young; Kim, Sun Whe; Han, Sae-Won; Oh, Do-Youn; Im, Seock-Ah; Kim, Tae-You; Bang, Yung-Jue; Jang, Ja-June; Ha, Sung W

    2013-01-01

    AIM: To evaluate the prognostic significance of CD24 expression in patients undergoing adjuvant chemoradiotherapy for extrahepatic bile duct (EHBD) cancer. METHODS: Eighty-four patients with EHBD cancer who underwent curative resection followed by adjuvant chemoradiotherapy were enrolled in this study. Postoperative radiotherapy was delivered to the tumor bed and regional lymph nodes up to a median of 40 Gy (range: 40-56 Gy). All patients also received fluoropyrimidine chemotherapy for radiosensitization during radiotherapy. CD24 expression was assessed with immunohistochemical staining on tissue microarray. Clinicopathologic factors as well as CD24 expression were evaluated in multivariate analysis for clinical outcomes including loco-regional recurrence, distant metastasis-free and overall survival. RESULTS: CD24 was expressed in 36 patients (42.9%). CD24 expression was associated with distant metastasis, but not with loco-regional recurrence nor with overall survival. The 5-year distant metastasis-free survival rates were 55.1% and 29.0% in patients with negative and positive expression, respectively (P = 0.0100). On multivariate analysis incorporating N stage, histologic differentiation and CD24 expression, N stage was the only significant factor predicting distant metastasis-free survival (P = 0.0089), while CD24 expression had borderline significance (P = 0.0733). In subgroup analysis, CD24 expression was significantly associated with 5-year distant metastasis-free survival in node-positive patients (38.4% with negative expression vs 0% with positive expression, P = 0.0110), but not in node-negative patients (62.0% with negative expression vs 64.0% with positive expression, P = 0.8599). CONCLUSION: CD24 expression was a significant predictor of distant metastasis for patients undergoing curative resection followed by adjuvant chemoradiotherapy especially for node-positive EHBD cancer. PMID:23539485

  10. Secondary photons and neutrinos from cosmic rays produced by distant blazars.

    Science.gov (United States)

    Essey, Warren; Kalashev, Oleg E; Kusenko, Alexander; Beacom, John F

    2010-04-09

    Secondary photons and neutrinos produced in the interactions of cosmic ray protons emitted by distant active galactic nuclei (AGN) with the photon background along the line of sight can reveal a wealth of new information about the intergalactic magnetic fields, extragalactic background light, and the acceleration mechanisms of cosmic rays. The secondary photons may have already been observed by gamma-ray telescopes. We show that the secondary neutrinos improve the prospects of discovering distant blazars by IceCube, and we discuss the ramifications for the cosmic backgrounds, magnetic fields, and AGN models.

  11. Controllable and fast quantum-information transfer between distant nodes in two-dimensional networks.

    Science.gov (United States)

    Zhong, Zhi-Rong

    2016-12-05

    We construct shortcuts to adiabatic passage to achieve controllable and fast quantum-information transfer (QIT) between arbitrary two distant nodes in a two-dimensional (2D) quantum network. Through suitable designing of time-dependent Rabi frequencies, we show that perfect QIT between arbitrary two distant nodes can be rapidly achieved. Numerical simulations demonstrate that the proposal is robust to the decoherence caused by atomic spontaneous emission and cavity photon leakage. Additionally, the proposed scheme is also insensitive to the variations of the experimental parameters. Thus, the proposed scheme provides a new perspective on robust quantum information processing in 2D quantum networks.

  12. Model of training of computer science teachers by means of distant education technologies

    Directory of Open Access Journals (Sweden)

    Т А Соловьева

    2009-03-01

    Full Text Available Training of future computer science teachers in conditions of informatization of education is analyzed. Distant educational technologies (DET and traditional process of training, their advantages and disadvantages are considered, active functions of DET as the basis of the model of training by means of DET is stressed. It is shown that mixed education combining both distant ant traditional technologies takes place on the basis of the created model. Practical use of the model is shown on the example of the course «Recursion» for future computer science teachers.

  13. Essays on nonlinear evolutionary game dynamics

    NARCIS (Netherlands)

    Ochea, M.I.

    2010-01-01

    Evolutionary game theory has been viewed as an evolutionary repair of rational actor game theory in the hope that a population of boundedly rational players may attain convergence to classic rational solutions, such as the Nash Equilibrium, via some learning or evolutionary process. In this thesis

  14. The citation field of evolutionary economics.

    NARCIS (Netherlands)

    Dolfsma, W.; Leydesdorff, L.

    2010-01-01

    Evolutionary economics has developed into an academic field of its own, institutionalized around, amongst others, the Journal of Evolutionary Economics (JEE). This paper analyzes the way and extent to which evolutionary economics has become an interdisciplinary journal, as its aim was: a journal

  15. The citation field of evolutionary economics

    NARCIS (Netherlands)

    Dolfsma, Wilfred; Leydesdorff, Loet

    2010-01-01

    Evolutionary economics has developed into an academic field of its own, institutionalized around, amongst others, the Journal of Evolutionary Economics (JEE). This paper analyzes the way and extent to which evolutionary economics has become an interdisciplinary journal, as its aim was: a journal

  16. Inductive Temporal Logic Programming

    OpenAIRE

    Kolter, Robert

    2009-01-01

    We study the extension of techniques from Inductive Logic Programming (ILP) to temporal logic programming languages. Therefore we present two temporal logic programming languages and analyse the learnability of programs from these languages from finite sets of examples. In first order temporal logic the following topics are analysed: - How can we characterize the denotational semantics of programs? - Which proof techniques are best suited? - How complex is the learning task? In propositional ...

  17. Indeterministic Temporal Logic

    Directory of Open Access Journals (Sweden)

    Trzęsicki Kazimierz

    2015-09-01

    Full Text Available The questions od determinism, causality, and freedom have been the main philosophical problems debated since the beginning of temporal logic. The issue of the logical value of sentences about the future was stated by Aristotle in the famous tomorrow sea-battle passage. The question has inspired Łukasiewicz’s idea of many-valued logics and was a motive of A. N. Prior’s considerations about the logic of tenses. In the scheme of temporal logic there are different solutions to the problem. In the paper we consider indeterministic temporal logic based on the idea of temporal worlds and the relation of accessibility between them.

  18. Evolutionary Theories in Environmental and Resource Economics: Approaches and Applications

    NARCIS (Netherlands)

    van den Bergh, J.C.J.M.; Gowdy, J.M.

    2000-01-01

    Recent advances in evolutionary theory have important implications for environmental economics. A short overview is offered of evolutionary thinking in economics. Subsequently, major concepts and approaches in evolutionary biology and evolutionary economics are presented and compared. Attention is

  19. Ultimate Realities: Deterministic and Evolutionary

    Science.gov (United States)

    Moxley, Roy A

    2007-01-01

    References to ultimate reality commonly turn up in the behavioral literature as references to determinism. However, this determinism is often difficult to interpret. There are different kinds of determinisms as well as different kinds of ultimate realities for a behaviorist to consider. To clarify some of the issues involved, the views of ultimate realities are treated as falling along a continuum, with extreme views of complete indeterminism and complete determinism at either end and various mixes in between. Doing so brings into play evolutionary realities and the movement from indeterminism to determinism, as in Peirce's evolutionary cosmology. In addition, this framework helps to show how the views of determinism by B. F. Skinner and other behaviorists have shifted over time. PMID:22478489

  20. Preventive evolutionary medicine of cancers.

    Science.gov (United States)

    Hochberg, Michael E; Thomas, Frédéric; Assenat, Eric; Hibner, Urszula

    2013-01-01

    Evolutionary theory predicts that once an individual reaches an age of sufficiently low Darwinian fitness, (s)he will have reduced chances of keeping cancerous lesions in check. While we clearly need to better understand the emergence of precursor states and early malignancies as well as their mitigation by the microenvironment and tissue architecture, we argue that lifestyle changes and preventive therapies based in an evolutionary framework, applied to identified high-risk populations before incipient neoplasms become clinically detectable and chemoresistant lineages emerge, are currently the most reliable way to control or eliminate early tumours. Specifically, the relatively low levels of (epi)genetic heterogeneity characteristic of many if not most incipient lesions will mean a relatively limited set of possible adaptive traits and associated costs compared to more advanced cancers, and thus a more complete and predictable understanding of treatment options and outcomes. We propose a conceptual model for preventive treatments and discuss the many associated challenges.

  1. Evolutionary neuroscience of cumulative culture.

    Science.gov (United States)

    Stout, Dietrich; Hecht, Erin E

    2017-07-24

    Culture suffuses all aspects of human life. It shapes our minds and bodies and has provided a cumulative inheritance of knowledge, skills, institutions, and artifacts that allows us to truly stand on the shoulders of giants. No other species approaches the extent, diversity, and complexity of human culture, but we remain unsure how this came to be. The very uniqueness of human culture is both a puzzle and a problem. It is puzzling as to why more species have not adopted this manifestly beneficial strategy and problematic because the comparative methods of evolutionary biology are ill suited to explain unique events. Here, we develop a more particularistic and mechanistic evolutionary neuroscience approach to cumulative culture, taking into account experimental, developmental, comparative, and archaeological evidence. This approach reconciles currently competing accounts of the origins of human culture and develops the concept of a uniquely human technological niche rooted in a shared primate heritage of visuomotor coordination and dexterous manipulation.

  2. Evolutionary model of stock markets

    Science.gov (United States)

    Kaldasch, Joachim

    2014-12-01

    The paper presents an evolutionary economic model for the price evolution of stocks. Treating a stock market as a self-organized system governed by a fast purchase process and slow variations of demand and supply the model suggests that the short term price distribution has the form a logistic (Laplace) distribution. The long term return can be described by Laplace-Gaussian mixture distributions. The long term mean price evolution is governed by a Walrus equation, which can be transformed into a replicator equation. This allows quantifying the evolutionary price competition between stocks. The theory suggests that stock prices scaled by the price over all stocks can be used to investigate long-term trends in a Fisher-Pry plot. The price competition that follows from the model is illustrated by examining the empirical long-term price trends of two stocks.

  3. Incorporating Development Into Evolutionary Psychology

    OpenAIRE

    David F. Bjorklund

    2016-01-01

    Developmental thinking is gradually becoming integrated within mainstream evolutionary psychology. This is most apparent with respect to the role of parenting, with proponents of life history theory arguing that cognitive and behavioral plasticity early in life permits children to select different life history strategies, with such strategies being adaptive solutions to different fitness trade-offs. I argue that adaptations develop and are based on the highly plastic nature of infants’ and ch...

  4. 76 FR 31351 - Safety Requirements and Manning Exemption Eligibility on Distant Water Tuna Fleet Vessels

    Science.gov (United States)

    2011-05-31

    ... exemption. For instance, the law requires that there be non-availability of United States licensed workers... allow a distant water tuna fleet vessel to engage foreign citizens under a temporary manning exemption... available in the docket and can be viewed by going to http://www.regulations.gov , inserting USCG- 2011-1146...

  5. The organization of local and distant functional connectivity in the human brain.

    Directory of Open Access Journals (Sweden)

    Jorge Sepulcre

    2010-06-01

    Full Text Available Information processing in the human brain arises from both interactions between adjacent areas and from distant projections that form distributed brain systems. Here we map interactions across different spatial scales by estimating the degree of intrinsic functional connectivity for the local (14 mm interactions. The balance between local and distant functional interactions measured at rest forms a map that separates sensorimotor cortices from heteromodal association areas and further identifies regions that possess both high local and distant cortical-cortical interactions. Map estimates of network measures demonstrate that high local connectivity is most often associated with a high clustering coefficient, long path length, and low physical cost. Task performance changed the balance between local and distant functional coupling in a subset of regions, particularly, increasing local functional coupling in regions engaged by the task. The observed properties suggest that the brain has evolved a balance that optimizes information-processing efficiency across different classes of specialized areas as well as mechanisms to modulate coupling in support of dynamically changing processing demands. We discuss the implications of these observations and applications of the present method for exploring normal and atypical brain function.

  6. UltraVISTA: A VISTA Public Survey of the Distant Universe

    NARCIS (Netherlands)

    McCracken, H. J.; Milvang-Jensen, B.; Dunlop, J.; Franx, M.; Fynbo, J. P. U.; Le Fèvre, O.; Holt, J.; Caputi, K. I.; Goranova, Y.; Buitrago, F.; Emerson, J.; Freudling, W.; Herent, O.; Hudelot, P.; López-Sanjuan, C.; Magnard, F.; Muzzin, A.; Mellier, Y.; Møller, P.; Nilsson, K. K.; Sutherland, W.; Tasca, L.; Zabl, J.

    2013-01-01

    Large samples of distant galaxies covering degree-scale areas are an unparalleled source of information concerning the first sources that ionised the Universe and the origin of cosmic structures. The UltraVISTA public survey, using the unique capabilities of the VISTA telescope, aims to assemble a

  7. UltraVISTA : A VISTA Public Survey of the Distant Universe

    NARCIS (Netherlands)

    McCracken, H. J.; Milvang-Jensen, B.; Dunlop, J.; Franx, M.; Fynbo, J. P. U.; Le Fèvre, O.; Holt, J.; Caputi, K. I.; Goranova, Y.; Buitrago, F.; Emerson, J.; Freudling, W.; Herent, O.; Hudelot, P.; López-Sanjuan, C.; Magnard, F.; Muzzin, A.; Mellier, Y.; Møller, P.; Nilsson, K. K.; Sutherland, W.; Tasca, L.; Zabl, J.

    2013-01-01

    Large samples of distant galaxies covering degree-scale areas are an unparalleled source of information concerning the first sources that ionised the Universe and the origin of cosmic structures. The UltraVISTA public survey, using the unique capabilities of the VISTA telescope, aims to assemble a

  8. Prognosis and determinants of outcome following locoregional or distant recurrence in patients with cutaneous melanoma

    NARCIS (Netherlands)

    Francken, Anne Brecht; Accortt, Neil A.; Shaw, Helen M.; Wiener, Martin; Soong, Seng-jaw; Hoekstra, Harald J.; Thompson, John F.

    Objective: Information on prognosis for patients with cutaneous melanoma after locoregional or distant recurrence is sparse and controversial. The aim of this study was to analyze factors influencing outcome after the development of a first relapse. Methods: Information was extracted from the Sydney

  9. The Detection and Photometric Redshift Determination of Distant Galaxies using SIRTF's Infrared Array Camera

    Science.gov (United States)

    Simpson, C.; Eisenhardt, P.

    1998-01-01

    We investigate the ability of the Space Infrared Telescope Facility's Infrared Array Camera to detect distant (z3) galaxies and measure their photometric redshifts. Our analysis shows that changing the original long wavelength filter specifications provides significant improvements in performance in this and other areas.

  10. The detection and photometric redshift determination of distant galaxies using SIRTF's Infrared Array Camera

    OpenAIRE

    Simpson, Chris; Eisenhardt, Peter

    1999-01-01

    We investigate the ability of the Space Infrared Telescope Facility's Infrared Array Camera to detect distant (z ~ 3)galaxies and measure their photometric redshifts. Our analysis shows that changing the original long wavelength filter specifications provides significant improvements in performance in this and other areas.

  11. Computer-Mediated Communication with Distant Friends: Relations with Adjustment during Students' First Semester in College

    Science.gov (United States)

    Ranney, John D.; Troop-Gordon, Wendy

    2012-01-01

    Because of recent technological innovations, college freshmen can readily communicate with friends who they see infrequently (e.g., friends from home). The current study addressed whether computer-mediated communication with these distant friends can compensate for a lack of high-quality on-campus friendships during students' first semester of…

  12. Dropping out of high school: Effects of close and distant friendships.

    Science.gov (United States)

    Carbonaro, William; Workman, Joseph

    2013-09-01

    Prior research highlights the role of friends in influencing whether a student completes high school. Students who drop out tend to have fewer friends, as well as friends who are less oriented toward school success. We distinguish between close and distant friendships by developing a theoretical framework which predicts close and distant friends likely have distinct effects on dropping out. Close friendships provide valuable emotional support, and forging numerous close friendships at school should decrease one's risk of dropping out. In contrast, the characteristics of distant friends help shape students' social identities and beliefs about "what's normative." Our analyses of the Add Health data set confirm our expectations. Students with more close friendships are less likely to drop out, but close friends' characteristics are unrelated to dropping out. Distant relationships (as measured by affect and regularity of interaction) with friends who have a high risk of dropping out significantly increase a student's own risk of dropping out. Copyright © 2013 Elsevier Inc. All rights reserved.

  13. Timing and Interstellar Scattering of 35 Distant Pulsars Discovered in the PALFA Survey

    NARCIS (Netherlands)

    Nice, D.J.; Altiere, A.; Bogdanov, S.; Cordes, J.M.; Farrington, D.; Hessels, J.W.T.; Kaspi, V.M.; Lyne, A.G.; Popa, L.; Ransom, S.M.; Sanpa-Arsa, S.; Stappers, B.W.; Wang, Y.; Allen, B.; Bhat, N.D.R.; Brazier, A.; Camilo, F.; Champion, D.J.; Chatterjee, S.; Crawford, F.; Deneva, J.S.; Desvignes, G.; Freire, P.C.C.; Jenet, F.A.; Knispel, B.; Lazarus, P.; Lee, K.J.; van Leeuwen, J.; Lorimer, D.R.; Lynch, R.; McLaughlin, M.A.; Scholz, P.; Siemens, X.; Stairs, I.H.; Stovall, K.; Venkataraman, A.; Zhu, W.

    2013-01-01

    We have made extensive observations of 35 distant slow (non-recycled) pulsars discovered in the ongoing Arecibo PALFA pulsar survey. Timing observations of these pulsars over several years at Arecibo Observatory and Jodrell Bank Observatory have yielded high-precision positions and measurements of

  14. The fates of Solar system analogues with one additional distant planet

    Science.gov (United States)

    Veras, Dimitri

    2016-12-01

    The potential existence of a distant planet (`Planet Nine') in the Solar system has prompted a re-think about the evolution of planetary systems. As the Sun transitions from a main-sequence star into a white dwarf, Jupiter, Saturn, Uranus and Neptune are currently assumed to survive in expanded but otherwise unchanged orbits. However, a sufficiently distant and sufficiently massive extra planet would alter this quiescent end scenario through the combined effects of Solar giant branch mass-loss and Galactic tides. Here, I estimate bounds for the mass and orbit of a distant extra planet that would incite future instability in systems with a Sun-like star and giant planets with masses and orbits equivalent to those of Jupiter, Saturn, Uranus and Neptune. I find that this boundary is diffuse and strongly dependent on each of the distant planet's orbital parameters. Nevertheless, I claim that instability occurs more often than not when the planet is as massive as Jupiter and harbours a semimajor axis exceeding about 300 au, or has a mass of a super-Earth and a semimajor axis exceeding about 3000 au. These results hold for orbital pericentres ranging from 100 to at least 400 au. This instability scenario might represent a common occurrence, as potentially evidenced by the ubiquity of metal pollution in white dwarf atmospheres throughout the Galaxy.

  15. Two Women with Multiple Disabilities Communicate with Distant Partners via a Special Text Messaging System

    Science.gov (United States)

    Lancioni, Giulio E.; O'Reilly, Mark F.; Singh, Nirbhay N.; Sigafoos, Jeff; Green, Vanessa A.; Oliva, Doretta; Alberti, Gloria; Carrella, Luigina

    2013-01-01

    This study extended the research on a special text messaging system, which allows persons with multiple disabilities to (a) write and send messages to distant partners and (b) have messages from those partners read out to them. The study involved two women with multiple disabilities (including blindness or minimal residual vision). The system…

  16. The CfA-Rosat Survey of Distant Clusters of Galaxies

    Science.gov (United States)

    McNamara, Brian

    1998-01-01

    We (Vikhlinin, McNamara, Forman, Jones, Hornstrup, Quintana) have completed a new survey of distant clusters of galaxies, which we use to to study cluster evolution over cosmological timescales. The clusters were identified as extended X-ray sources in 650 ROSAT PSPC images of high Galactic latitude fields. Our catalog of approximately 230 extended X-ray sources covers 160 square degrees on the sky. Ours is the largest of the several ROSAT serendipitous cluster surveys in progress (e.g. SHARC, Rosati, WARPS etc.). Using V,R,I imagery obtained at several observatories, we find that greater than 90% of the X-ray sources are associated with distant clusters of galaxies. We have obtained spectroscopic redshifts for nearly 80 clusters in our catalog, and we have measured photometric redshifts for the remaining clusters. Our sample contains more than 20 clusters at z > 0.5. I will discuss the logN-logS relationship for our clusters. Because our large survey area, we are able to confirm the evolution of the most luminous distant clusters first seen in the Einstein Extended Medium Sensitivity Survey. In addition, I will discuss the relationships between optical richness, core radius, and X-ray luminosity for distant, X-ray-selected clusters.

  17. Temporal properties of stereopsis

    NARCIS (Netherlands)

    Gheorghiu, E.

    2005-01-01

    The goal of the research presented in this thesis was to investigate temporal properties of disparity processing and depth perception in human subjects, in response to dynamic stimuli. The results presented in various chapters, reporting findings about different temporal aspects of disparity

  18. Temporal Linear System Structure

    NARCIS (Netherlands)

    Willigenburg, van L.G.; Koning, de W.L.

    2008-01-01

    Piecewise constant rank systems and the differential Kalman decomposition are introduced in this note. Together these enable the detection of temporal uncontrollability/unreconstructability of linear continuous-time systems. These temporal properties are not detected by any of the four conventional

  19. Evolutionary ecology of virus emergence.

    Science.gov (United States)

    Dennehy, John J

    2017-02-01

    The cross-species transmission of viruses into new host populations, termed virus emergence, is a significant issue in public health, agriculture, wildlife management, and related fields. Virus emergence requires overlap between host populations, alterations in virus genetics to permit infection of new hosts, and adaptation to novel hosts such that between-host transmission is sustainable, all of which are the purview of the fields of ecology and evolution. A firm understanding of the ecology of viruses and how they evolve is required for understanding how and why viruses emerge. In this paper, I address the evolutionary mechanisms of virus emergence and how they relate to virus ecology. I argue that, while virus acquisition of the ability to infect new hosts is not difficult, limited evolutionary trajectories to sustained virus between-host transmission and the combined effects of mutational meltdown, bottlenecking, demographic stochasticity, density dependence, and genetic erosion in ecological sinks limit most emergence events to dead-end spillover infections. Despite the relative rarity of pandemic emerging viruses, the potential of viruses to search evolutionary space and find means to spread epidemically and the consequences of pandemic viruses that do emerge necessitate sustained attention to virus research, surveillance, prophylaxis, and treatment. © 2016 New York Academy of Sciences.

  20. Incorporating Development Into Evolutionary Psychology

    Directory of Open Access Journals (Sweden)

    David F. Bjorklund

    2016-09-01

    Full Text Available Developmental thinking is gradually becoming integrated within mainstream evolutionary psychology. This is most apparent with respect to the role of parenting, with proponents of life history theory arguing that cognitive and behavioral plasticity early in life permits children to select different life history strategies, with such strategies being adaptive solutions to different fitness trade-offs. I argue that adaptations develop and are based on the highly plastic nature of infants’ and children’s behavior/cognition/brains. The concept of evolved probabilistic cognitive mechanisms is introduced, defined as information processing mechanisms evolved to solve recurrent problems faced by ancestral populations that are expressed in a probabilistic fashion in each individual in a generation and are based on the continuous and bidirectional interaction over time at all levels of organization, from the genetic through the cultural. Early perceptual/cognitive biases result in behavior that, when occurring in a species-typical environment, produce continuous adaptive changes in behavior (and cognition, yielding adaptive outcomes. Examples from social learning and tool use are provided, illustrating the development of adaptations via evolved probabilistic cognitive mechanisms. The integration of developmental concepts into mainstream evolutionary psychology (and evolutionary concepts into mainstream developmental psychology will provide a clearer picture of what it means to be human.

  1. What's wrong with evolutionary biology?

    Science.gov (United States)

    Welch, John J

    2017-01-01

    There have been periodic claims that evolutionary biology needs urgent reform, and this article tries to account for the volume and persistence of this discontent. It is argued that a few inescapable properties of the field make it prone to criticisms of predictable kinds, whether or not the criticisms have any merit. For example, the variety of living things and the complexity of evolution make it easy to generate data that seem revolutionary (e.g. exceptions to well-established generalizations, or neglected factors in evolution), and lead to disappointment with existing explanatory frameworks (with their high levels of abstraction, and limited predictive power). It is then argued that special discontent stems from misunderstandings and dislike of one well-known but atypical research programme: the study of adaptive function, in the tradition of behavioural ecology. To achieve its goals, this research needs distinct tools, often including imaginary agency, and a partial description of the evolutionary process. This invites mistaken charges of narrowness and oversimplification (which come, not least, from researchers in other subfields), and these chime with anxieties about human agency and overall purpose. The article ends by discussing several ways in which calls to reform evolutionary biology actively hinder progress in the field.

  2. The evolutionary dynamics of language.

    Science.gov (United States)

    Steels, Luc; Szathmáry, Eörs

    2018-02-01

    The well-established framework of evolutionary dynamics can be applied to the fascinating open problems how human brains are able to acquire and adapt language and how languages change in a population. Schemas for handling grammatical constructions are the replicating unit. They emerge and multiply with variation in the brains of individuals and undergo selection based on their contribution to needed expressive power, communicative success and the reduction of cognitive effort. Adopting this perspective has two major benefits. (i) It makes a bridge to neurobiological models of the brain that have also adopted an evolutionary dynamics point of view, thus opening a new horizon for studying how human brains achieve the remarkably complex competence for language. And (ii) it suggests a new foundation for studying cultural language change as an evolutionary dynamics process. The paper sketches this novel perspective, provides references to empirical data and computational experiments, and points to open problems. Copyright © 2017 The Authors. Published by Elsevier B.V. All rights reserved.

  3. Exaptation, adaptation, and evolutionary psychology.

    Science.gov (United States)

    Schulz, Armin

    2013-01-01

    One of the most well known methodological criticisms of evolutionary psychology is Gould's claim that the program pays too much attention to adaptations, and not enough to exaptations. Almost as well known is the standard rebuttal of that criticism: namely, that the study of exaptations in fact depends on the study of adaptations. However, as I try to show in this paper, it is premature to think that this is where this debate ends. First, the notion of exaptation that is commonly used in this debate is different from the one that Gould and Vrba originally defined. Noting this is particularly important, since, second, the standard reply to Gould's criticism only works if the criticism is framed in terms of the former notion of exaptation, and not the latter. However, third, this ultimately does not change the outcome of the debate much, as evolutionary psychologists can respond to the revamped criticism of their program by claiming that the original notion of exaptation is theoretically and empirically uninteresting. By discussing these issues further, I also seek to determine, more generally, which ways of approaching the adaptationism debate in evolutionary biology are useful, and which not.

  4. Temporal Photon Differentials

    DEFF Research Database (Denmark)

    Schjøth, Lars; Frisvad, Jeppe Revall; Erleben, Kenny

    2010-01-01

    , constituting a temporal smoothing of rapidly changing illumination. In global illumination temporal smoothing can be achieved with distribution ray tracing (Cook et al., 1984). Unfortunately, this, and resembling methods, requires a high temporal resolution as samples has to be drawn from in-between frames. We...... present a novel method which is able to produce high quality temporal smoothing for indirect illumination without using in-between frames. Our method is based on ray differentials (Igehy, 1999) as it has been extended in (Sporring et al., 2009). Light rays are traced as bundles creating footprints, which......The finite frame rate also used in computer animated films is cause of adverse temporal aliasing effects. Most noticeable of these is a stroboscopic effect that is seen as intermittent movement of fast moving illumination. This effect can be mitigated using non-zero shutter times, effectively...

  5. Distant Relations

    DEFF Research Database (Denmark)

    Bülow, Anne Marie; Lee, Joyce y. H.; Panteli, Niki

    2016-01-01

    This article explores the role of email in the ambiguous circumstances of an established international partnership that is developing into competition. Using the naturally occurring interaction of a longitudinal ethnographic study, we study the ensuing task and relationship conflicts through the ...

  6. Distant Wanderers

    Science.gov (United States)

    McKay, Christopher P.

    Gaze out into the night sky and wonder: Are we alone? Are there stars like our Sun, with planets like Earth, with life—with complex, and even intelligent, life? We've known for many decades now that there are stars like our Sun. Indeed, we orbit an unremarkable star. But now we have begun to push the question one step further; we know now that there are planets around other stars. Within the past decade, astronomers have discovered large planets orbiting close to Sun-like stars. This is arguably the most exciting result in astronomy for the past twenty years and could herald the beginning of an age of planetary discovery leading to the ultimate prize: the detection of Earth-size planets orbiting in the habitable zone of Sun-like stars.

  7. Genome-wide investigation reveals high evolutionary rates in annual model plants

    Directory of Open Access Journals (Sweden)

    Araki Hitoshi

    2010-11-01

    factors that have genome-wide influence, most likely those associated with annual/perennial life history. Although we acknowledge current limitations of this kind of study, mainly due to a small sample size available and a distant taxonomic relationship of the model organisms, our results indicate that the genome-wide survey is a promising approach toward further understanding of the mechanism determining the molecular evolutionary rate at the genomic level.

  8. [Lymph node and distant metastases of thyroid gland cancer. Metastases in the thyroid glands].

    Science.gov (United States)

    Schmid, K W

    2015-11-01

    The different biological features of the various major entities of thyroid cancer, e.g. papillary, follicular, poorly differentiated, anaplastic and medullary, depend to a large extent on their different metastatic spread. Papillary thyroid cancer (PTC) has a propensity for cervical lymphatic spread that occurs in 20-50 % of patients whereas distant metastasis occurs in thyroid cancer (FTC) has a marked propensity for vascular but not lymphatic invasion and 10-20 % of FTC develop distant metastases. At the time of diagnosis approximately one third of medullary thyroid cancer (MTC) cases show lymph node metastases, in 10-15 % distant metastases and 25 % develop metastases during the course of the disease. Poorly differentiated (PDTC) and anaplastic thyroid cancer (ATC) spread via both lymphatic and vascular invasion. Thus distant metastases are relatively uncommon in DTC and when they occur, long-term stable disease is the typical clinical course. The major sites of distant metastases are the lungs and bone. Metastases to the brain, breasts, liver, kidneys, muscle and skin are relatively rare or even rare. The thyroid gland itself can be a site of metastases from a variety of other tumors. In autopsy series of patients with disseminated cancer disease, metastases to the thyroid gland were found in up to 10 % of cases. Metastases from other primary tumors to the thyroid gland have been reported in 1.4-3 % of patients who have surgery for suspected cancer of the thyroid gland. The most common primary cancers that metastasize to the thyroid gland are renal cell (48.1 %), colorectal (10.4 %), lung (8.3 %) and breast cancer (7.8 %) and surprisingly often sarcomas (4.0 %).

  9. Distant metastasis as the sole initial manifestation of well-differentiated thyroid carcinoma.

    Science.gov (United States)

    See, Anna; Iyer, N Gopalakrishna; Tan, Ngian Chye; Teo, Constance; Ng, Jeremy; Soo, Khee Chee; Tan, Hiang Khoon

    2017-07-01

    Thyroid carcinoma usually presents as a neck lump. Distant metastasis as the sole initial manifestation of well-differentiated thyroid carcinoma (WDTC) is rare and little is known about these patients. The aim of this study is to characterize patients who present with distant metastasis as the sole initial manifestation of WDTC. Retrospective review of case records of WDTC seen at the National Cancer Centre Singapore from 2002 to 2015 was performed. Patients with no prior complaint of neck swelling and whose first presentation was distant metastatic WDTC were included. Patient demographics, disease characteristics, radiological imaging, histopathology, types of treatment administered, and survival outcomes were examined. Nineteen out of seven hundred and thirty-two cases fulfilled inclusion criteria. Mean age was 65.4 years. All patients presented with osseous (36.8%), pulmonary (31.6%), cerebral metastases (5.3%), or a combination of two out of three aforementioned sites (26.3%). Follicular thyroid carcinoma was most common (47.4%), followed by papillary (36.8%) and medullary (15.8%). More than two-thirds of patients had multiple metastatic foci. Thirteen out of nineteen patients (68.4%) underwent total thyroidectomy with or without neck dissection and adjuvant RAI, while the rest declined surgery. The mean length of follow-up was 40.1 ± 5.1 months and 5-year disease-specific survival was 48.0 ± 17.2%. Distant metastasis without a history of neck swelling as the initial presentation of WDTC is extremely rare. Osseous metastasis and follicular thyroid carcinoma are the most common metastatic site and etiology, respectively. Disease-specific survival at 5-year post-diagnosis is lower compared to patients with thyroid carcinoma diagnosed with distant metastasis on further work-up.

  10. Opposite Effects of Coinjection and Distant Injection of Mesenchymal Stem Cells on Breast Tumor Cell Growth.

    Science.gov (United States)

    Zheng, Huilin; Zou, Weibin; Shen, Jiaying; Xu, Liang; Wang, Shu; Fu, Yang-Xin; Fan, Weimin

    2016-09-01

    : Mesenchymal stem cells (MSCs) usually promote tumor growth and metastasis. By using a breast tumor 4T1 cell-based animal model, this study determined that coinjection and distant injection of allogeneic bone marrow-derived MSCs with tumor cells could exert different effects on tumor growth. Whereas the coinjection of MSCs with 4T1 cells promoted tumor growth, surprisingly, the injection of MSCs at a site distant from the 4T1 cell inoculation site suppressed tumor growth. We further observed that, in the distant injection model, MSCs decreased the accumulation of myeloid-derived suppressor cells and regulatory T cells in tumor tissues by enhancing proinflammatory factors such as interferon-γ, tumor necrosis factor-α, Toll-like receptor (TLR)-3, and TLR-4, promoting host antitumor immunity and inhibiting tumor growth. Unlike previous reports, this is the first study reporting that MSCs may exert opposite roles on tumor growth in the same animal model by modulating the host immune system, which may shed light on the potential application of MSCs as vehicles for tumor therapy and other clinical applications. Mesenchymal stem cells (MSCs) have been widely investigated for their potential roles in tissue engineering, autoimmune diseases, and tumor therapeutics. This study explored the impact of coinjection and distant injection of allogeneic bone marrow-derived MSCs on mouse 4T1 breast cancer cells. The results showed that the coinjection of MSCs and 4T1 cells promoted tumor growth. MSCs might act as the tumor stromal precursors and cause immunosuppression to protect tumor cells from immunosurveillance, which subsequently facilitated tumor metastasis. Interestingly, the distant injection of MSCs and 4T1 cells suppressed tumor growth. Together, the results of this study revealed the dual functions of MSCs in immunoregulation. ©AlphaMed Press.

  11. Application of conditional probability analysis to distant metastases from lung cancer.

    Science.gov (United States)

    Oikawa, Akihiro; Takahashi, Hideto; Ishikawa, Hiroichi; Kurishima, Koichi; Kagohashi, Katsunori; Satoh, Hiroaki

    2012-03-01

    The aim of this study was to reveal whether there was non-randomness in the occurrence of metastasis and, if the non-randomness was denied, whether there were specific metastatic patterns in lung cancer patients. Patients who presented with pathologically diagnosed lung cancer between January 1986 and March 2009 at our hospitals were included. A statistical method and conditional probability analysis were used to analyze the data. Under the condition of one metastatic organ A (lung, bone, brain, liver or adrenal gland; the 5 most common metastatic organs), we determined the conditional probability of distant metastasis to a specific organ B, which was written as P(B | A), and compared it with the probability of distant metastasis P(B). The study group consisted of 1,994 patients. Of the 1,994 patients, 839 (42.1%) had distant metastases at the time of the initial diagnosis of lung cancer. With the exception of the comparisons between P(lung) and P(lung | adrenal gland) and between P(adrenal gland) and P(adrenal gland | lung), there were statistically significant differences between P(B | A) and P(B) in the 5 metastatic organs. In addition, P(B | A) and P(C | B | A) varied according to each organ and P(confined to A), P(confined to A and B) and P(confined to A, B and C) were different in each metastatic organ. In lung cancer patients, distant metastasis occurred non-randomly and there may be certain specific patterns of distant metastasis. The accumulation of knowledge of specific patterns of metastasis may aid the approach to individualized treatments.

  12. Adaptation measures to drought in Mongolian rangeland: The long-distant movement of people and livestock

    Science.gov (United States)

    Kakinuma, K.; Kanae, S.

    2015-12-01

    Coping with droughts are one of the most important issues in arid and semi-arid regions. Mongolia, where are located in central Asia, are concerned the increase of droughts in the future (IPCC 2014). Mongolia has long history of livestock grazing. Herders have developed the mobile grazing systems to use spatiotemporal variable vegetation. Especially, they often take a rapid and long-distant movement to avoid drought condition ("otor" in Mongolia). The movement is a main adaptation measure to droughts for herders, and it would be applicable to other regions where will be increase the frequency of droughts in the future. However there are few knowledge about processes and actual conditions of the long-distant movement of herders and livestock across Mongolia. Therefore our objective is to discuss the long-distance movement as adaptation measures to droughts. Mongolia has a climatic gradient along the latitude; rainfall variability in southern regions are higher than that in northern regions. Previous theoretical studies predicted that rainfall variability affect the grazing strategies. Based on them, we established two hypotheses about the relationship between climatic variability and the form of long distant movement. (1) The long-distance movement likely occur in southern regions because the frequency of drought are higher in southern regions than in northern regions (2) Cooperation among herders, such as acceptance of livestock that from other prefectures, are likely occur in southern regions while exclusive management are likely occur in northern regions. We interviewed to local herders, decision makers about the long-distant movement, and investigated the number of livestock that across the border of prefectures in recent year across Mongolia. We will discuss long-distant movements as an adaptation measure to drought thorough these results.

  13. Transcriptionally-active human papillomavirus is consistently retained in the distant metastases of primary oropharyngeal carcinomas.

    Science.gov (United States)

    Mehrad, Mitra; Zhao, Hongwei; Gao, Ge; Wang, Xiaowei; Lewis, James S

    2014-06-01

    High-risk human papillomavirus (HPV) is both causative and prognostic in the majority of oropharyngeal squamous cell carcinomas (OPSCCs). The aim of this study was to evaluate for transcriptionally-active HPV in matched primary OPSCCs and their distant metastases given the implications of HPV status for diagnosis and treatment. Twenty matched pairs of primary OPSCC and their distant metastases were retrieved from departmental files. Two study pathologists reviewed all cases to confirm the diagnoses and to evaluate histologic features. Real-time PCR (RT-PCR) for detection of E6/E7 mRNA for all major high-risk HPV types and p16 immunohistochemistry were performed. Distant metastases were to lung (70 %), bone (20 %), non-regional lymph nodes (5 %) and pericardium (5 %). Histologically, 15 primary tumors were nonkeratinizing, 3 nonkeratinizing with maturation, one basaloid, and one keratinizing. Seventeen (85 %) of the metastases had the same histologic type as the primary tumor. All 20 matched pairs were concordant for HPV status by RT-PCR and for p16 expression with 19 of 20 cases positive for high risk HPV and one negative. HPV types were concordant in all cases. These findings show that the distant metastases from HPV-related primary OPSCCs uniformly retain transcriptionally-active HPV and p16 overexpression. They also retain similar morphology. This argues that HPV status can be utilized to differentiate metastatic OPSCC from separate, new, primary squamous cell carcinomas in other organs, and that therapies specifically targeting HPV or virus-related proteins in patients with distant metastases can be utilized.

  14. Temporal properties of stereopsis

    Science.gov (United States)

    Gheorghiu, E.

    2005-03-01

    The goal of the research presented in this thesis was to investigate temporal properties of disparity processing and depth perception in human subjects, in response to dynamic stimuli. The results presented in various chapters, reporting findings about different temporal aspects of disparity processing, are based on psychophysical experiments and computational model analysis. In chapter 1 we investigated which processes of binocular depth perception in dynamic random-dot stereograms (DRS), i.e., tolerance for interocular delays and temporal integration of correlation, are responsible for the temporal flexibility of the stereoscopic system. Our results demonstrate that (i) disparities from simultaneous monocular inputs dominate those from interocular delayed inputs; (ii) stereopsis is limited by temporal properties of monocular luminance mechanisms; (iii) depth perception in DRS results from cross-correlation-like operation on two simultaneous monocular inputs that represent the retinal images after having been subjected to a process of monocular temporal integration of luminance. In chapter 2 we examined what temporal information is exploited by the mechanisms underlying stereoscopic motion in depth. We investigated systematically the influence of temporal frequency on binocular depth perception in temporally correlated and temporally uncorrelated DRS. Our results show that disparity-defined depth is judged differently in temporally correlated and uncorrelated DRS above a temporal frequency of about 3 Hz. The results and simulations indicate that: (i) above about 20 Hz, the complete absence of stereomotion is caused by temporal integration of luminance; (ii) the difference in perceived depth in temporally correlated and temporally uncorrelated DRS for temporal frequencies between 20 and 3 Hz, is caused by temporal integration of disparity. In chapter 3 we investigated temporal properties of stereopsis at different spatial scales in response to sustained and

  15. Multiple explanations in Darwinian evolutionary theory.

    Science.gov (United States)

    Bock, Walter J

    2010-03-01

    Variational evolutionary theory as advocated by Darwin is not a single theory, but a bundle of related but independent theories, namely: (a) variational evolution; (b) gradualism rather than large leaps; (c) processes of phyletic evolution and of speciation; (d) causes for the formation of varying individuals in populations and for the action of selective agents; and (e) all organisms evolved from a common ancestor. The first four are nomological-deductive explanations and the fifth is historical-narrative. Therefore evolutionary theory must be divided into nomological and historical theories which are both testable against objective empirical observations. To be scientific, historical evolutionary theories must be based on well corroborated nomological theories, both evolutionary and functional. Nomological and general historical evolutionary theories are well tested and must be considered as strongly corroborated scientific theories. Opponents of evolutionary theory are concerned only with historical evolutionary theories, having little interest in nomological theory. Yet given a well corroborated nomological evolutionary theory, historical evolutionary theories follow automatically. If understood correctly, both forms of evolutionary theories stand on their own as corroborated scientific theories and should not be labeled as facts.

  16. Towards Temporal Graph Databases

    OpenAIRE

    Campos, Alexander; Mozzino, Jorge; Vaisman, Alejandro

    2016-01-01

    In spite of the extensive literature on graph databases (GDBs), temporal GDBs have not received too much attention so far. Temporal GBDs can capture, for example, the evolution of social networks across time, a relevant topic in data analysis nowadays. In this paper we propose a data model and query language (denoted TEG-QL) for temporal GDBs, based on the notion of attribute graphs. This allows a straightforward translation to Neo4J, a well-known GBD. We present extensive examples of the use...

  17. INFLUENCE OF RADIOLOGICALLY AND CYTOLOGICALLY ASSESSED DISTANT METASTASES ON THE SURVIVAL OF PATIENTS WITH ESOPHAGEAL AND GASTROESOPHAGEAL JUNCTION CARCINOMA

    NARCIS (Netherlands)

    VANOVERHAGEN, H; BERGER, MY; MEIJERS, H; TILANUS, HW; KOK, TC; STIJNEN, T; LAMERIS, JS

    1993-01-01

    Background. Distant metastasis in carcinoma of the esophagus and gastroesophageal junction is associated with a poor survival after resection. To improve the selection of patients for surgical and nonsurgical treatment, this study determined the influence on survival of distant metastases, as

  18. One shot, one kill: the forces delivered by archer fish shots to distant targets.

    Science.gov (United States)

    Burnette, Morgan F; Ashley-Ross, Miriam A

    2015-10-01

    Archer fishes are skillful hunters of terrestrial prey, firing jets of water that dislodge insects perched on overhead vegetation. In the current investigation, we sought an answer to the question: are distant targets impractical foraging choices? Targets far from the shooter might not be hit with sufficient force to cause them to fall. However, observations from other investigators show that archer fish fire streams of water that travel in a non-ballistic fashion, which is thought to keep on-target forces high, even to targets that are several body lengths distant from the fish. We presented targets at different distances and investigated three aspects of foraging behavior: (i) on-target forces, (ii) shot velocity, (iii) a two-target choice assay to determine if fish would show any preference for downing closer targets or more distant targets. In general, shots from our fish (Toxotes chatareus) showed a mild decrease (less than 15% on average) in on-target forces at our most distant target offered (5.8 body lengths) with respect to the closest target offered (2.3 body lengths). One individual in our investigation showed slightly, but significantly, greater on-target forces as target distance increased. Forces on the furthest targets offered were found to double that of attachment forces for 200mg insects, even for individuals whose on-target forces showed mild decreases with increases in target distance. High-speed video analysis of jet impact with the target revealed that the shot was traveling in a non-ballistic manner, even to our most distant target offered, corroborating previous suppositions that on-target forces should remain high. Fish were able to accomplish this without large changes to shot velocity, but we did find evidence that the water jets appeared to differ in the timing of their acceleration as target distance increased. Our two-target choice experiment revealed that fish show preference for downing the closer target first, even though impact

  19. Temporal degradation of data limits biodiversity research.

    Science.gov (United States)

    Tessarolo, Geiziane; Ladle, Richard; Rangel, Thiago; Hortal, Joaquin

    2017-09-01

    Spatial and/or temporal biases in biodiversity data can directly influence the utility, comparability, and reliability of ecological and evolutionary studies. While the effects of biased spatial coverage of biodiversity data are relatively well known, temporal variation in data quality (i.e., the congruence between recorded and actual information) has received much less attention. Here, we develop a conceptual framework for understanding the influence of time on biodiversity data quality based on three main processes: (1) the natural dynamics of ecological systems-such as species turnover or local extinction; (2) periodic taxonomic revisions, and; (3) the loss of physical and metadata due to inefficient curation, accidents, or funding shortfalls. Temporal decay in data quality driven by these three processes has fundamental consequences for the usage and comparability of data collected in different time periods. Data decay can be partly ameliorated by adopting standard protocols for generation, storage, and sharing data and metadata. However, some data degradation is unavoidable due to natural variations in ecological systems. Consequently, changes in biodiversity data quality over time need be carefully assessed and, if possible, taken into account when analyzing aging datasets.

  20. Evolutionary Accessibility of Mutational Pathways

    Science.gov (United States)

    Franke, Jasper; Klözer, Alexander; de Visser, J. Arjan G. M.; Krug, Joachim

    2011-01-01

    Functional effects of different mutations are known to combine to the total effect in highly nontrivial ways. For the trait under evolutionary selection (‘fitness’), measured values over all possible combinations of a set of mutations yield a fitness landscape that determines which mutational states can be reached from a given initial genotype. Understanding the accessibility properties of fitness landscapes is conceptually important in answering questions about the predictability and repeatability of evolutionary adaptation. Here we theoretically investigate accessibility of the globally optimal state on a wide variety of model landscapes, including landscapes with tunable ruggedness as well as neutral ‘holey’ landscapes. We define a mutational pathway to be accessible if it contains the minimal number of mutations required to reach the target genotype, and if fitness increases in each mutational step. Under this definition accessibility is high, in the sense that at least one accessible pathway exists with a substantial probability that approaches unity as the dimensionality of the fitness landscape (set by the number of mutational loci) becomes large. At the same time the number of alternative accessible pathways grows without bounds. We test the model predictions against an empirical 8-locus fitness landscape obtained for the filamentous fungus Aspergillus niger. By analyzing subgraphs of the full landscape containing different subsets of mutations, we are able to probe the mutational distance scale in the empirical data. The predicted effect of high accessibility is supported by the empirical data and is very robust, which we argue reflects the generic topology of sequence spaces. Together with the restrictive assumptions that lie in our definition of accessibility, this implies that the globally optimal configuration should be accessible to genome wide evolution, but the repeatability of evolutionary trajectories is limited owing to the presence of a

  1. Evolutionary Origin of the Proepicardium

    Directory of Open Access Journals (Sweden)

    Elena Cano

    2013-05-01

    Full Text Available The embryonic epicardium and the cardiac mesenchyme derived from it are critical to heart development. The embryonic epicardium arises from an extracardiac progenitor tissue called the proepicardium, a proliferation of coelomic cells located at the limit between the liver and the sinus venosus. A proepicardium has not been described in invertebrates, and the evolutionary origin of this structure in vertebrates is unknown. We herein suggest that the proepicardium might be regarded as an evolutionary derivative from an ancient pronephric external glomerulus that has lost its excretory role. In fact, we previously described that the epicardium arises by cell migration from the primordia of the right pronephric external glomerulus in a representative of the most primitive vertebrate lineage, the lamprey Petromyzon marinus. In this review, we emphasize the striking similarities between the gene expression profiles of the proepicardium and the developing kidneys, as well as the parallelisms in the signaling mechanisms involved in both cases. We show some preliminary evidence about the existence of an inhibitory mechanism blocking glomerular differentiation in the proepicardium. We speculate as to the possibility that this developmental link between heart and kidney can be revealing a phylogenetically deeper association, supported by the existence of a heart-kidney complex in Hemichordates. Finally, we suggest that primitive hematopoiesis could be related with this heart-kidney complex, thus accounting for the current anatomical association of the hematopoietic stem cells with an aorta-gonad-mesonephros area. In summary, we think that our hypothesis can provide new perspectives on the evolutionary origin of the vertebrate heart.

  2. Positive temporal dependence of the biological clock implies hyperbolic discounting

    Directory of Open Access Journals (Sweden)

    Debajyoti eRay

    2011-01-01

    Full Text Available Temporal preferences of animals and humans often exhibit inconsistencies, whereby an earlier, smaller reward may be preferred when it occurs immediately but not when it is delayed. Such choices reflect hyperbolic discounting of future rewards, rather than the exponential discounting required for temporal consistency. Simultaneously, however, evidence has emerged that suggests that animals and humans have an internal representation of time that often differs from the calendar time used in detection of temporal inconsistencies. Here, we prove that temporal inconsistencies emerge if fixed durations in calendar time are experienced as positively related (positive quadrant dependent. Hence, what are time-consistent choices within the time framework of the decision maker appear as time-inconsistent to an outsider who analyzes choices in calendar time. As the biological clock becomes more variable, the fit of the hyperbolic discounting model improves. A recent alternative explanation for temporal choice inconsistencies builds on persistent under-estimation of the length of distant time intervals. By increasing the expected speed of our stochastic biological clock for time farther into the future, we can emulate this explanation. Ours is therefore an encompassing theoretical framework that predicts context-dependent degrees of intertemporal choice inconsistencies, to the extent that context can generate changes in autocorrelation, variability, and expected speed of the biological clock. Our finding should lead to novel experiments that will clarify the role of time perception in impulsivity, with critical implications for, among others, our understanding of aging, drug abuse and pathological gambling.

  3. Metabolism at Evolutionary Optimal States

    Directory of Open Access Journals (Sweden)

    Iraes Rabbers

    2015-06-01

    Full Text Available Metabolism is generally required for cellular maintenance and for the generation of offspring under conditions that support growth. The rates, yields (efficiencies, adaptation time and robustness of metabolism are therefore key determinants of cellular fitness. For biotechnological applications and our understanding of the evolution of metabolism, it is necessary to figure out how the functional system properties of metabolism can be optimized, via adjustments of the kinetics and expression of enzymes, and by rewiring metabolism. The trade-offs that can occur during such optimizations then indicate fundamental limits to evolutionary innovations and bioengineering. In this paper, we review several theoretical and experimental findings about mechanisms for metabolic optimization.

  4. The Evolutionary Theory of Depression.

    Science.gov (United States)

    Gałecki, Piotr; Talarowska, Monika

    2017-05-13

    The evolutionary success of Homo sapiens is attributed to the following two factors: the upright body posture (which freed our hands and allowed unconstrained operation of various objects) and intensive development of the frontal lobes, mainly the Broca area of the brain. Underlining the uniqueness of the human brain, we often forget about the fact that the frontal lobes - the most developed part of the brain - are at the same time our greatest weakness, exposed to the action of damaging factors in our evolving environment. Is depression the cost of evolution?

  5. Historical change and evolutionary theory.

    Science.gov (United States)

    Masters, Roger D

    2007-09-01

    Despite advances in fields like genetics, evolutionary psychology, and human behavior and evolution--which generally focus on individual or small group behavior from a biological perspective--evolutionary biology has made little impact on studies of political change and social history. Theories of natural selection often seem inapplicable to human history because our social behavior is embedded in language (which makes possible the concepts of time and social identity on which what we call "history" depends). Peter Corning's Holistic Darwinism reconceptualizes evolutionary biology, making it possible to go beyond the barriers separating the social and natural sciences. Corning focuses on two primary processes: "synergy" (complex multivariate interactions at multiple levels between a species and its environment) and "cybernetics" (the information systems permitting communication between individuals and groups over time). Combining this frame of reference with inclusive fitness theory, it is possible to answer the most important (and puzzling) question in human history: How did a species that lived for millennia in hunter-gatherer bands form centralized states governing large populations of non-kin (including multi-ethnic empires as well as modern nation-states)? The fragility and contemporary ethnic violence in Kenya and the Congo should suffice as evidence that these issues need to be taken seriously. To explain the rise and fall of states as well as changes in human laws and customs--the core of historical research--it is essential to show how the provision of collective goods can overcome the challenge of self-interest and free-riding in some instances, yet fail to do so in others. To this end, it is now possible to consider how a state providing public goods can--under circumstances that often include effective leadership--contribute to enhanced inclusive fitness of virtually all its members. Because social behavior needs to adapt to ecology, but ecological

  6. Evolutionary relationships among pollinators and repeated pollinator sharing in sexually deceptive orchids.

    Science.gov (United States)

    Phillips, R D; Brown, G R; Dixon, K W; Hayes, C; Linde, C C; Peakall, R

    2017-09-01

    The mechanism of pollinator attraction is predicted to strongly influence both plant diversification and the extent of pollinator sharing between species. Sexually deceptive orchids rely on mimicry of species-specific sex pheromones to attract their insect pollinators. Given that sex pheromones tend to be conserved among related species, we predicted that in sexually deceptive orchids, (i) pollinator sharing is rare, (ii) closely related orchids use closely related pollinators and (iii) there is strong bias in the wasp lineages exploited by orchids. We focused on species that are pollinated by sexual deception of thynnine wasps in the distantly related genera Caladenia and Drakaea, including new field observations for 45 species of Caladenia. Specialization was extreme with most orchids using a single pollinator species. Unexpectedly, seven cases of pollinator sharing were found, including two between Caladenia and Drakaea, which exhibit strikingly different floral morphology. Phylogenetic analysis of pollinators using four nuclear sequence loci demonstrated that although orchids within major clades primarily use closely related pollinator species, up to 17% of orchids within these clades are pollinated by a member of a phylogenetically distant wasp genus. Further, compared to the total diversity of thynnine wasps within the study region, orchids show a strong bias towards exploiting certain genera. Although these patterns may arise through conservatism in the chemical classes used in sex pheromones, apparent switches between wasp clades suggest unexpected flexibility in floral semiochemical production. Alternatively, wasp sex pheromones within lineages may exhibit greater chemical diversity than currently appreciated. © 2017 European Society For Evolutionary Biology. Journal of Evolutionary Biology © 2017 European Society For Evolutionary Biology.

  7. Temporal Lobe Seizure

    Science.gov (United States)

    ... pregnancy Temporal lobe seizure Symptoms & causes Diagnosis & treatment Advertisement Mayo Clinic does not endorse companies or products. ... a Job Site Map About This Site Twitter Facebook Google YouTube Pinterest Mayo Clinic is a not- ...

  8. Temporal Lobe Seizure

    Science.gov (United States)

    ... functions, including having odd feelings — such as euphoria, deja vu or fear. During a temporal lobe seizure, you ... include: A sudden sense of unprovoked fear A deja vu experience — a feeling that what's happening has happened ...

  9. Multisensory temporal numerosity judgment

    NARCIS (Netherlands)

    Philippi, T.; Erp, J.B.F. van; Werkhoven, P.J.

    2008-01-01

    In temporal numerosity judgment, observers systematically underestimate the number of pulses. The strongest underestimations occur when stimuli are presented with a short interstimulus interval (ISI) and are stronger for vision than for audition and touch. We investigated if multisensory

  10. Neocortical Temporal Lobe Epilepsy

    Science.gov (United States)

    Bercovici, Eduard; Kumar, Balagobal Santosh; Mirsattari, Seyed M.

    2012-01-01

    Complex partial seizures (CPSs) can present with various semiologies, while mesial temporal lobe epilepsy (mTLE) is a well-recognized cause of CPS, neocortical temporal lobe epilepsy (nTLE) albeit being less common is increasingly recognized as separate disease entity. Differentiating the two remains a challenge for epileptologists as many symptoms overlap due to reciprocal connections between the neocortical and the mesial temporal regions. Various studies have attempted to correctly localize the seizure focus in nTLE as patients with this disorder may benefit from surgery. While earlier work predicted poor outcomes in this population, recent work challenges those ideas yielding good outcomes in part due to better localization using improved anatomical and functional techniques. This paper provides a comprehensive review of the diagnostic workup, particularly the application of recent advances in electroencephalography and functional brain imaging, in neocortical temporal lobe epilepsy. PMID:22953057

  11. Massive temporal lobe cholesteatoma

    National Research Council Canada - National Science Library

    Waidyasekara, Pasan; Dowthwaite, Samuel A; Stephenson, Ellison; Bhuta, Sandeep; McMonagle, Brent

    2015-01-01

    .... There had been no relevant symptoms in the interim until 6 weeks prior to this presentation. Imaging demonstrated a large right temporal lobe mass contiguous with the middle ear and mastoid cavity with features consistent with cholesteatoma...

  12. Massive Temporal Lobe Cholesteatoma

    National Research Council Canada - National Science Library

    Waidyasekara, Pasan; Dowthwaite, Samuel A; Stephenson, Ellison; Bhuta, Sandeep; McMonagle, Brent

    2015-01-01

    .... There had been no relevant symptoms in the interim until 6 weeks prior to this presentation. Imaging demonstrated a large right temporal lobe mass contiguous with the middle ear and mastoid cavity with features consistent with cholesteatoma...

  13. Evolutionary developmental biology its roots and characteristics.

    Science.gov (United States)

    Morange, Michel

    2011-09-01

    The rise of evolutionary developmental biology was not the progressive isolation and characterization of developmental genes and gene networks. Many obstacles had to be overcome: the idea that all genes were more or less involved in development; the evidence that developmental processes in insects had nothing in common with those of vertebrates. Different lines of research converged toward the creation of evolutionary developmental biology, giving this field of research its present heterogeneity. This does not prevent all those working in the field from sharing the conviction that a precise characterization of evolutionary variations is required to fully understand the evolutionary process. Some evolutionary developmental biologists directly challenge the Modern Synthesis. I propose some ways to reconcile these apparently opposed visions of evolution. The turbulence seen in evolutionary developmental biology reflects the present entry of history into biology. Copyright © 2011 Elsevier Inc. All rights reserved.

  14. The Evolving Theory of Evolutionary Radiations.

    Science.gov (United States)

    Simões, M; Breitkreuz, L; Alvarado, M; Baca, S; Cooper, J C; Heins, L; Herzog, K; Lieberman, B S

    2016-01-01

    Evolutionary radiations have intrigued biologists for more than 100 years, and our understanding of the patterns and processes associated with these radiations continues to grow and evolve. Recently it has been recognized that there are many different types of evolutionary radiation beyond the well-studied adaptive radiations. We focus here on multifarious types of evolutionary radiations, paying special attention to the abiotic factors that might trigger diversification in clades. We integrate concepts such as exaptation, species selection, coevolution, and the turnover-pulse hypothesis (TPH) into the theoretical framework of evolutionary radiations. We also discuss other phenomena that are related to, but distinct from, evolutionary radiations that have relevance for evolutionary biology. Copyright © 2015 Elsevier Ltd. All rights reserved.

  15. An Evolutionary Perspective on Toxic Leadership

    OpenAIRE

    Lucia Ovidia VREJA; Balan, Sergiu,; Loredana Cornelia BOSCA

    2016-01-01

    Charles Darwin’s prediction from 1859, that future psychology was going to be built on principles derived from evolutionary theory came at last to be fulfilled. Nowadays, there are at least four disciplines that attempt to explain human behaviours as evolutionary adaptations (or maladaptations) to the natural and/or social environment: human sociobiology, human behavioural ecology, evolutionary psychology, memetics and gene–culture coevolution theory (in our view, the most adequate of all). A...

  16. High-order epistasis shapes evolutionary trajectories.

    OpenAIRE

    Sailer, Zachary R.; Harms, Michael J.

    2017-01-01

    High-order epistasis-where the effect of a mutation is determined by interactions with two or more other mutations-makes small, but detectable, contributions to genotype-fitness maps. While epistasis between pairs of mutations is known to be an important determinant of evolutionary trajectories, the evolutionary consequences of high-order epistasis remain poorly understood. To determine the effect of high-order epistasis on evolutionary trajectories, we computationally removed high-order epis...

  17. High-order epistasis shapes evolutionary trajectories

    OpenAIRE

    Sailer, Zachary R.

    2017-01-01

    High-order epistasis?where the effect of a mutation is determined by interactions with two or more other mutations?makes small, but detectable, contributions to genotype-fitness maps. While epistasis between pairs of mutations is known to be an important determinant of evolutionary trajectories, the evolutionary consequences of high-order epistasis remain poorly understood. To determine the effect of high-order epistasis on evolutionary trajectories, we computationally removed high-order epis...

  18. Evolutionary Theories of Aging and Longevity

    OpenAIRE

    Gavrilov, Leonid A.; Gavrilova, Natalia S.

    2002-01-01

    The purpose of this article is to provide students and researchers entering the field of aging studies with an introduction to the evolutionary theories of aging, as well as to orient them in the abundant modern scientific literature on evolutionary gerontology. The following three major evolutionary theories of aging are discussed: 1) the theory of programmed death suggested by August Weismann, 2) the mutation accumulation theory of aging suggested by Peter Medawar, and 3) the antagonistic p...

  19. An introduction to evolutionary developmental psychology.

    Science.gov (United States)

    Machluf, Karin; Liddle, James R; Bjorklund, David F

    2014-04-29

    Evolutionary developmental psychology represents a synthesis of modern evolutionary theory and developmental psychology. Here we introduce the special issue on evolutionary developmental psychology by briefly discussing the history of this field and then summarizing the variety of topics that are covered. In this special issue, leading researchers provide a collection of theoretical and empirical articles that highlight recent findings and propose promising areas for future research.

  20. An Introduction to Evolutionary Developmental Psychology

    OpenAIRE

    Karin Machluf; James R. Liddle; David F. Bjorklund

    2014-01-01

    Evolutionary developmental psychology represents a synthesis of modern evolutionary theory and developmental psychology. Here we introduce the special issue on evolutionary developmental psychology by briefly discussing the history of this field and then summarizing the variety of topics that are covered. In this special issue, leading researchers provide a collection of theoretical and empirical articles that highlight recent findings and propose promising areas for future research.

  1. An Introduction to Evolutionary Developmental Psychology

    Directory of Open Access Journals (Sweden)

    Karin Machluf

    2014-04-01

    Full Text Available Evolutionary developmental psychology represents a synthesis of modern evolutionary theory and developmental psychology. Here we introduce the special issue on evolutionary developmental psychology by briefly discussing the history of this field and then summarizing the variety of topics that are covered. In this special issue, leading researchers provide a collection of theoretical and empirical articles that highlight recent findings and propose promising areas for future research.

  2. Atypical Distant Metastasis of Breast Malignant Phyllodes Tumors: A Case Report and Literature Review

    Directory of Open Access Journals (Sweden)

    Tiphaine de Foucher

    2017-01-01

    Full Text Available Malignant phyllodes tumors (MPT are rare breast neoplasms. Preoperative diagnosis is often challenging due to the unspecific clinical, radiological, and histological characteristics of the tumor. Dissemination pathways are local with chest wall invasion, regional with lymph nodes metastasis, and distant, hematogenous, mostly to the lungs, bones, and brain. Distant metastasis (DM can be synchronous or appear months to years after the diagnosis and initial management. The current report describes the case of a 57-year-old woman presenting with a giant/neglected MPT of the breast, with no DM at initial staging, treated by radical modified mastectomy. Motor disorders due to medullar compression by a paravertebral mass appeared at short follow-up, also treated surgically. The patient died from several DM of rapid evolution. To our knowledge, this is the only case described of MPT with metastases to soft tissue causing medullar compression. We present a literature review on unusual metastatic localizations of MPT.

  3. TIMING AND INTERSTELLAR SCATTERING OF 35 DISTANT PULSARS DISCOVERED IN THE PALFA SURVEY

    Energy Technology Data Exchange (ETDEWEB)

    Nice, D. J. [Department of Physics, Lafayette College, Easton, PA 18042 (United States); Altiere, E.; Farrington, D.; Popa, L.; Wang, Y. [Department of Physics, Bryn Mawr College, Bryn Mawr, PA 19010 (United States); Bogdanov, S.; Camilo, F. [Columbia Astrophysics Laboratory, Columbia University, New York, NY 10027 (United States); Cordes, J. M.; Brazier, A.; Chatterjee, S. [Astronomy Department, Cornell University, Ithaca, NY 14853 (United States); Hessels, J. W. T. [ASTRON, The Netherlands Institute for Radio Astronomy, Postbus 2, 7990-AA Dwingeloo (Netherlands); Kaspi, V. M. [Department of Physics, McGill University, Montreal, QC H3A 2T8 (Canada); Lyne, A. G.; Stappers, B. W. [Jodrell Bank Centre for Astrophysics, School of Physics and Astronomy, University of Manchester, Manchester M13 9PL (United Kingdom); Ransom, S. M. [NRAO, Charlottesville, VA 22903 (United States); Sanpa-arsa, S. [Department of Astronomy, University of Virginia, Charlottesville, VA 22903 (United States); Allen, B. [Max-Planck-Institut fuer Gravitationsphysik, D-30167 Hannover (Germany); Bhat, N. D. R. [Center for Astrophysics and Supercomputing, Swinburne University, Hawthorn, Victoria 3122 (Australia); Champion, D. J. [Max-Planck-Institut fuer Radioastronomie, D-53121 Bonn (Germany); Crawford, F. [Department of Physics and Astronomy, Franklin and Marshall College, Lancaster, PA 17604-3003 (United States); and others

    2013-07-20

    We have made extensive observations of 35 distant slow (non-recycled) pulsars discovered in the ongoing Arecibo PALFA pulsar survey. Timing observations of these pulsars over several years at Arecibo Observatory and Jodrell Bank Observatory have yielded high-precision positions and measurements of rotation properties. Despite being a relatively distant population, these pulsars have properties that mirror those of the previously known pulsar population. Many of the sources exhibit timing noise, and one underwent a small glitch. We have used multifrequency data to measure the interstellar scattering properties of these pulsars. We find scattering to be higher than predicted along some lines of sight, particularly in the Cygnus region. Finally, we present XMM-Newton and Chandra observations of the youngest and most energetic of the pulsars, J1856+0245, which has previously been associated with the GeV-TeV pulsar wind nebula HESS J1857+026.

  4. Distant Ureteral Metastasis from Colon Adenocarcinoma: Report of a Case and Review of the Literature

    Directory of Open Access Journals (Sweden)

    Ferakis Nikolaos

    2014-01-01

    Full Text Available Carcinomas arising from organs neighbouring the ureter can directly infiltrate the ureter. Distant ureteral metastasis from colon adenocarcinoma is extremely rare and usually an incidental finding in performed autopsies. We report a case of a right ureteral metastasis in a 65-year-old Caucasian male with a history of rectal cancer for which he had been treated 4 years before. He presented with asymptomatic moderate right hydronephrosis. The patient underwent a right nephroureterectomy. Histology of the ureter revealed transmural adenocarcinoma with infiltration of the mucosa. Infiltration of the muscular coat of the bladder was found 2 years later. Thus, cystectomy and left ureterocutaneostomy were performed. The patient died 6 months later due to toxic megacolon during chemotherapy. The differential diagnosis of ureteral adenocarcinoma, especially in patients with previous history of colon adenocarcinoma, should include the possibility of distant metastasis from the primary colonic tumor.

  5. Investigations in the Spectral Properties of Operators with Distant Perturbations (survey

    Directory of Open Access Journals (Sweden)

    A. M. Golovina

    2015-01-01

    Full Text Available We propose a chronological overview of researches on operators with distant perturbations. Let us explain what "distant perturbations" mean. An elementary example of the operator with distant perturbations is a differential operator of the second order with two finite potentials. Supports of these operators are at a great distance from each other, i.e. they are \\distant".The study of such operators has been performed since the middle of the last century, mostly by foreign researchers see eg. R. Ahlrichs, T. Aktosun, M. Klaus, P. Aventini, P. Exner, E.B. Davies, V. Graffi, E.V. Harrell II, H.J. Silverstone, M. Mebkhout, R. Hoegh-Krohn, W. Hun ziker, V. Kostrykin, R. Schrader, J.D. Morgan (III, Y. Pinchover, O.K. Reity, H. Tamura, X. Wang, Y. Wang, S. Kondej, B. Simon, I. Veselic, D.I. Borisov, A.M. Golovina. The main objects of their investigation were the asymptotic behaviors of eigenvalues and corresponding eigenfunctions of perturbed operators. In several papers the research was focused on resolvents and eigenvalues of perturbed operator arising from the edge of the essential spectrum. The main results of the past century are the first members of the asymptotics of perturbed eigenvalues and the corresponding eigenfunctions and the first members of the asymptotics of resolvents of the perturbed operators. The main results of the last fifteen years are full asymptotic expansions for the eigenvalues and their corresponding functions and an explicit formula for the resolvent of the perturbed operator.In this paper, we also note that up to 2004 only different kind of potentials were considered as perturbing operators, and Laplace and Dirac operators were considered as unperturbed operators. Only since 2004, nonpotential perturbing operators appeared in the literature. Since 2012, an arbitrary elliptic differential operator is considered as an unperturbed operator.We propose a classification of investigations on distant perturbations, based on the

  6. An opto-magneto-mechanical quantum interface between distant superconducting qubits

    Science.gov (United States)

    Xia, Keyu; Vanner, Michael R.; Twamley, Jason

    2014-07-01

    A quantum internet, where widely separated quantum devices are coherently connected, is a fundamental vision for local and global quantum information networks and processing. Superconducting quantum devices can now perform sophisticated quantum engineering locally on chip and a detailed method to achieve coherent optical quantum interconnection between distant superconducting devices is a vital, but highly challenging, goal. We describe a concrete opto-magneto-mechanical system that can interconvert microwave-to-optical quantum information with high fidelity. In one such node we utilise the magnetic fields generated by the supercurrent of a flux qubit to coherently modulate a mechanical oscillator that is part of a high-Q optical cavity to achieve high fidelity microwave-to-optical quantum information exchange. We analyze the transfer between two spatially distant nodes connected by an optical fibre and using currently accessible parameters we predict that the fidelity of transfer could be as high as ~80%, even with significant loss.

  7. Atypical Distant Metastasis of Breast Malignant Phyllodes Tumors: A Case Report and Literature Review

    Science.gov (United States)

    de Foucher, Tiphaine; Roussel, Hélène; Hivelin, Mikael; Rossi, Léa; Cornou, Caroline; Bats, Anne-Sophie; Deloménie, Myriam; Lécuru, Fabrice

    2017-01-01

    Malignant phyllodes tumors (MPT) are rare breast neoplasms. Preoperative diagnosis is often challenging due to the unspecific clinical, radiological, and histological characteristics of the tumor. Dissemination pathways are local with chest wall invasion, regional with lymph nodes metastasis, and distant, hematogenous, mostly to the lungs, bones, and brain. Distant metastasis (DM) can be synchronous or appear months to years after the diagnosis and initial management. The current report describes the case of a 57-year-old woman presenting with a giant/neglected MPT of the breast, with no DM at initial staging, treated by radical modified mastectomy. Motor disorders due to medullar compression by a paravertebral mass appeared at short follow-up, also treated surgically. The patient died from several DM of rapid evolution. To our knowledge, this is the only case described of MPT with metastases to soft tissue causing medullar compression. We present a literature review on unusual metastatic localizations of MPT.

  8. PRECISION MEASUREMENT OF THE MOST DISTANT SPECTROSCOPICALLY CONFIRMED SUPERNOVA Ia WITH THE HUBBLE SPACE TELESCOPE

    Energy Technology Data Exchange (ETDEWEB)

    Rubin, D.; Rykoff, E.; Aldering, G.; Barbary, K.; Fakhouri, H. K.; Goldhaber, G.; Hsiao, E. Y. [E. O. Lawrence Berkeley National Lab, 1 Cyclotron Road, Berkeley, CA 94720 (United States); Knop, R. A. [Quest University Canada, Squamish, BC (Canada); Amanullah, R.; Goobar, A. [The Oskar Klein Centre, Department of Physics, AlbaNova, Stockholm University, SE-106 91 Stockholm (Sweden); Burns, M. S. [Colorado College, 14 East Cache La Poudre Street, Colorado Springs, CO 80903 (United States); Conley, A. [Center for Astrophysics and Space Astronomy, 389 UCB, University of Colorado, Boulder, CO 80309 (United States); Connolly, N. [Hamilton College Department of Physics, Clinton, NY 13323 (United States); Deustua, S.; Fruchter, A. S. [Space Telescope Science Institute, 3700 San Martin Drive, Baltimore, MD 21218 (United States); Fadeyev, V. [Santa Cruz Institute for Particle Physics, University of California Santa Cruz, Santa Cruze, CA 94064 (United States); Gibbons, R. A. [Department of Physics and Astronomy, Vanderbilt University, Nashville, TN 37240 (United States); Huang, X. [Department of Physics, University of California Berkeley, Berkeley, CA 94720 (United States); Kowalski, M. [Physikalisches Institut Universitaet Bonn (Germany); Lidman, C. [Australian Astronomical Observatory, P.O. Box 296, Epping, NSW 1710 (Australia); Collaboration: Supernova Cosmology Project; and others

    2013-01-20

    We report the discovery of a redshift 1.71 supernova in the GOODS-North field. The Hubble Space Telescope (HST) ACS spectrum has almost negligible contamination from the host or neighboring galaxies. Although the rest-frame-sampled range is too blue to include any Si II line, a principal component analysis allows us to confirm it as a Type Ia supernova with 92% confidence. A recent serendipitous archival HST WFC3 grism spectrum contributed a key element of the confirmation by giving a host-galaxy redshift of 1.713 {+-} 0.007. In addition to being the most distant SN Ia with spectroscopic confirmation, this is the most distant Ia with a precision color measurement. We present the ACS WFC and NICMOS 2 photometry and ACS and WFC3 spectroscopy. Our derived supernova distance is in agreement with the prediction of {Lambda}CDM.

  9. ChIP-seq Mapping of Distant-Acting Enhancers and Their In Vivo Activities

    Energy Technology Data Exchange (ETDEWEB)

    Visel, Axel; Pennacchio, Len A.

    2011-06-01

    The genomic location and function of most distant-acting transcriptional enhancers in the human genome remains unknown We performed ChIP-seq for various transcriptional coactivator proteins (such as p300) directly from different embryonic mouse tissues, identifying thousands of binding sitesTransgenic mouse experiments show that p300 and other co-activator peaks are highly predictive of genomic location AND tissue-specific activity patterns of distant-acting enhancersMost enhancers are active only in one or very few tissues Genomic location of tissue-specific p300 peaks correlates with tissue-specific expression of nearby genes Most binding sites are conserved, but the global degree of conservation varies between tissues

  10. Evolutionary conservation of regulatory elements in vertebrate HOX gene clusters

    Energy Technology Data Exchange (ETDEWEB)

    Santini, Simona; Boore, Jeffrey L.; Meyer, Axel

    2003-12-31

    Due to their high degree of conservation, comparisons of DNA sequences among evolutionarily distantly-related genomes permit to identify functional regions in noncoding DNA. Hox genes are optimal candidate sequences for comparative genome analyses, because they are extremely conserved in vertebrates and occur in clusters. We aligned (Pipmaker) the nucleotide sequences of HoxA clusters of tilapia, pufferfish, striped bass, zebrafish, horn shark, human and mouse (over 500 million years of evolutionary distance). We identified several highly conserved intergenic sequences, likely to be important in gene regulation. Only a few of these putative regulatory elements have been previously described as being involved in the regulation of Hox genes, while several others are new elements that might have regulatory functions. The majority of these newly identified putative regulatory elements contain short fragments that are almost completely conserved and are identical to known binding sites for regulatory proteins (Transfac). The conserved intergenic regions located between the most rostrally expressed genes in the developing embryo are longer and better retained through evolution. We document that presumed regulatory sequences are retained differentially in either A or A clusters resulting from a genome duplication in the fish lineage. This observation supports both the hypothesis that the conserved elements are involved in gene regulation and the Duplication-Deletion-Complementation model.

  11. Robust Estimation of Evolutionary Distances with Information Theory.

    Science.gov (United States)

    Cao, Minh Duc; Allison, Lloyd; Dix, Trevor I; Bodén, Mikael

    2016-05-01

    Methods for measuring genetic distances in phylogenetics are known to be sensitive to the evolutionary model assumed. However, there is a lack of established methodology to accommodate the trade-off between incorporating sufficient biological reality and avoiding model overfitting. In addition, as traditional methods measure distances based on the observed number of substitutions, their tend to underestimate distances between diverged sequences due to backward and parallel substitutions. Various techniques were proposed to correct this, but they lack the robustness against sequences that are distantly related and of unequal base frequencies. In this article, we present a novel genetic distance estimate based on information theory that overcomes the above two hurdles. Instead of examining the observed number of substitutions, this method estimates genetic distances using Shannon's mutual information. This naturally provides an effective framework for balancing model complexity and goodness of fit. Our distance estimate is shown to be approximately linear to elapsed time and hence is less sensitive to the divergence of sequence data and compositional biased sequences. Using extensive simulation data, we show that our method 1) consistently reconstructs more accurate phylogeny topologies than existing methods, 2) is robust in extreme conditions such as diverged phylogenies, unequal base frequencies data, and heterogeneous mutation patterns, and 3) scales well with large phylogenies. © The Author 2016. Published by Oxford University Press on behalf of the Society for Molecular Biology and Evolution. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  12. Evolutionary Lightsailing Missions for the 100-Year Starship

    Science.gov (United States)

    Friedman, L.; Garber, D.; Heinsheimer, T.

    Incremental milestones towards interstellar flight can be achieved in this century by building on first steps with lightsailing, the only known technology that might someday take us to the stars. That this is now possible is enabled by achievements of first solar sail flights, the use of nano-technology for miniaturization of spacecraft, advances in information processing and the decoding of our genomes into transportable form. This paper quantifies a series of robotic steps through and beyond the solar system that are practical and would stimulate the development of new technologies in guidance, navigation, materials, communication, sensors, information processing etc. while exploring ever-more distant, exciting space objectives at distances impractical for classical rocket-based technologies. There robotic steps may be considered as precursors to human interstellar flight, but they may also be considered as evolutionary steps that provide for a different future: One of virtual human interstellar flight that may bypass the ideas of the past (big rockets launching heavy people) in favour of those of the future ­ networking amongst the stars with information, and the physical transport of digital and biological genomes.

  13. Evolutionary Autonomous Health Monitoring System (EAHMS) Project

    Data.gov (United States)

    National Aeronautics and Space Administration — For supporting NASA's Robotics, Tele-Robotics and Autonomous Systems Roadmap, we are proposing the "Evolutionary Autonomous Health Monitoring System" (EAHMS) for...

  14. Child murder by parents and evolutionary psychology.

    Science.gov (United States)

    Friedman, Susan Hatters; Cavney, James; Resnick, Phillip J

    2012-12-01

    This article explores the contribution of evolutionary theory to the understanding of causation and motive in filicide cases and also reviews special issues in the forensic evaluation of alleged perpetrators of filicide. Evolutionary social psychology seeks to understand the context in which our brains evolved, to understand human behaviors. The authors propose evolutionary theory as a framework theory to meaningfully appreciate research about filicide. Using evolutionary psychology as a theoretical lens, this article reviews the research on filicide over the past 40 years, and describes epidemiologic and typologic studies of filicide, and theoretical analyses from a range of disciplines. Copyright © 2012 Elsevier Inc. All rights reserved.

  15. Evolutionary medicine: its scope, interest and potential

    National Research Council Canada - National Science Library

    Stephen C. Stearns

    2012-01-01

    .... It first describes the range of topics covered by evolutionary medicine, which include human genetic variation, mismatches to modernity, reproductive medicine, degenerative disease, hostpathogen...

  16. Evolutionary psychology: its programs, prospects, and pitfalls.

    Science.gov (United States)

    Neher, Andrew

    2006-01-01

    The emerging specialty of evolutionary psychology presents a challenge to mainstream psychology. It proposes that cognitive, notjust more fundamental, traits in humans are grounded in dedicated evolutionary programs. Specifically, it maintains that the common assumption in psychology-that the complexities of our psyches have been largely freed from evolutionary constraints and are instead based in a general learning capacity-is mistaken. The major premises of evolutionary psychology are examined in light of arguments and evidence presented by both supporters and detractors. Although some of these premises are well grounded, others are questionable and limit the development of the specialty and its integration into mainstream psychology.

  17. An introduction to comparative evolutionary psychology.

    Science.gov (United States)

    Vonk, Jennifer; Shackelford, Todd K

    2013-07-18

    Previously we (Vonk and Shackelford, 2012, in press) proposed an integration of comparative psychology and evolutionary psychology into a new field of "comparative evolutionary psychology." This integrative discipline incorporates principles from ethology, ecology, biology, anthropology, and psychology, broadly defined. We present in this special issue a collection of original empirical and theoretical review articles in which leading researchers propose ways to successfully integrate comparative and evolutionary approaches within their particular areas of study. We showcase the key contributions of these articles and highlight several empirical and theoretical challenges, as well as key future directions, for comparative evolutionary psychology.

  18. Support, attention and distant guidance for chronic pain patients. Case report

    OpenAIRE

    Moretti,Felipe Azevedo; Barsottini, Claudia Galindo Novoa

    2017-01-01

    ABSTRACT BACKGROUND AND OBJECTIVES: Mutual help among patients and distant support tools - such as phone calls and online discussions - are promising strategies to manage chronic conditions, however still poorly explored in the context of pain. This study aimed at evaluating two different remote guidance methods able to help chronic patients: (I) phone calls and (II) engagement in online discussion groups for patients. CASE REPORT: To evaluate these two assistance models, a qualitative rese...

  19. The Influence of Diabetes Mellitus and Metformin on Distant Metastases in Oropharyngeal Cancer: A Multicenter Study

    Energy Technology Data Exchange (ETDEWEB)

    Spratt, Daniel E. [Department of Radiation Oncology, Memorial Sloan Kettering Cancer Center, New York, New York (United States); Beadle, Beth M. [Department of Radiation Oncology, The University of Texas MD Anderson Cancer Center, Houston, Texas (United States); Zumsteg, Zachary S., E-mail: zachary.zumsteg@cshs.org [Department of Radiation Oncology, Memorial Sloan Kettering Cancer Center, New York, New York (United States); Department of Radiation Oncology, Cedars-Sinai Medical Center, Los Angeles, California (United States); Rivera, Andrew [Department of Radiation Oncology, Memorial Sloan Kettering Cancer Center, New York, New York (United States); Skinner, Heath D. [Bobby R. Alford Department of Otolaryngology–Head and Neck Surgery, Baylor College of Medicine, Houston, Texas (United States); Osborne, Joseph R. [Department of Radiology, Memorial Sloan Kettering Cancer Center, New York, New York (United States); Garden, Adam S. [Department of Radiation Oncology, The University of Texas MD Anderson Cancer Center, Houston, Texas (United States); Lee, Nancy Y. [Department of Radiation Oncology, Memorial Sloan Kettering Cancer Center, New York, New York (United States)

    2016-03-01

    Purpose: Local control in oropharyngeal cancer has improved to unprecedented rates with combined modality therapy; as a result, distant metastases are becoming a principal challenge. We aimed to determine the impact of diabetes mellitus and metformin use on clinical outcomes in a large population of oropharyngeal cancer patients treated in the modern era. Methods and Materials: We identified 1745 consecutive patients with oropharyngeal cancer treated at 2 large cancer centers with external beam radiation therapy from 1998 to 2011. A total of 184 patients had diabetes mellitus at the time of diagnosis, of whom 102 were taking metformin. The outcomes assessed included local failure-free survival (LFFS), regional failure-free survival (RFFS), distant metastasis-free survival (DMFS), and overall survival (OS). Results: The median follow-up time was 4.3 years. The 5-year actuarial rates of DMFS were 89.6% for nondiabetic patients and 78.7% for diabetic nonmetformin users (P=.011) and of OS were 83.0% for nondiabetic patients and 70.7% for diabetic nonmetformin users (P=.048). Diabetic metformin users had 5-year DMFS (90.1%) and OS (89.6%) similar to those of nondiabetic patients. Multivariate analysis (diabetic nonmetformin users as reference) demonstrated improved DMFS for nondiabetic patients (adjusted hazard ratio 0.54; 95% confidence interval 0.32-0.93; P=.03) and a trend toward improved DMFS with metformin use (adjusted hazard ratio 0.46; 95% confidence interval 0.20-1.04; P=.06). LFFS and RFFS were high in all groups and were not significantly different by diabetic status or metformin use. Conclusions: Diabetic patients not using metformin independently have significantly higher rates of distant metastases than do nondiabetic patients, whereas metformin users have rates of distant metastases similar to those of nondiabetic patients. Further prospective investigation is warranted to validate the benefit of metformin in oropharyngeal cancer.

  20. Trabecular Bone Loss at a Distant Skeletal Site Following Noninvasive Knee Injury in Mice

    OpenAIRE

    Christiansen, Blaine A.; Emami, Armaun J.; Fyhrie, David P.; Satkunananthan, Patrick B.; Hardisty, Michael R.

    2015-01-01

    Traumatic injuries can have systemic consequences, as the early inflammatory response after trauma can lead to tissue destruction at sites not affected by the initial injury. This systemic catabolism may occur in the skeleton following traumatic injuries such as anterior cruciate ligament (ACL) rupture. However, bone loss following injury at distant, unrelated skeletal sites has not yet been established. In the current study, we utilized a mouse knee injury model to determine whether acute kn...

  1. Validation of the 18-gene classifier as a prognostic biomarker of distant metastasis in breast cancer.

    Directory of Open Access Journals (Sweden)

    Skye Hung-Chun Cheng

    Full Text Available We validated an 18-gene classifier (GC initially developed to predict local/regional recurrence after mastectomy in estimating distant metastasis risk. The 18-gene scoring algorithm defines scores as: <21, low risk; ≥21, high risk. Six hundred eighty-three patients with primary operable breast cancer and fresh frozen tumor tissues available were included. The primary outcome was the 5-year probability of freedom from distant metastasis (DMFP. Two external datasets were used to test the predictive accuracy of 18-GC. The 5-year rates of DMFP for patients classified as low-risk (n = 146, 21.7% and high-risk (n = 537, 78.6% were 96.2% (95% CI, 91.1%-98.8% and 80.9% (74.6%-81.9%, respectively (median follow-up interval, 71.8 months. The 5-year rates of DMFP of the low-risk group in stage I (n = 62, 35.6%, stage II (n = 66, 20.1%, and stage III (n = 18, 10.3% were 100%, 94.2% (78.5%-98.5%, and 90.9% (50.8%-98.7%, respectively. Multivariate analysis revealed that 18-GC is an independent prognostic factor of distant metastasis (adjusted hazard ratio, 5.1; 95% CI, 1.8-14.1; p = 0.0017 for scores of ≥21. External validation showed that the 5-year rate of DMFP in the low- and high-risk patients was 94.1% (82.9%-100% and 80.3% (70.7%-89.9%, p = 0.06 in a Singapore dataset, and 89.5% (81.9%-94.1% and 73.6% (67.2%-79.0%, p = 0.0039 in the GEO-GSE20685 dataset, respectively. In conclusion, 18-GC is a viable prognostic biomarker for breast cancer to estimate distant metastasis risk.

  2. Evaluation of distant results after lamivudine discontinuation in children with chronic hepatitis B.

    Directory of Open Access Journals (Sweden)

    Lech Chyczewski

    2010-08-01

    Full Text Available The aim of this study was to estimate distant results after discontinuation of long term lamivudine treatment in children with chronic hepatitis B. Furthermore, the emergence of HBV polymerase gene variants in YMDD motif during therapy was examined. Additionally, the most commonly occurring type of mutation in the polymerase YMDD region were investigated. The study involved 27 HBeAg positive children with chronic hepatitis B. Children included to lamivudine therapy were previously treated without effects with interferon alpha.

  3. Distant Cutaneous Metastases of Prostate Cancer: A Report of 2 Cases.

    Science.gov (United States)

    Rodríguez-Lojo, R; Castiñeiras, I; Rey-Sanjurjo, J L; Fernández-Díaz, M L

    2016-09-01

    Cutaneous metastases of prostate cancer are extremely rare. We present 2 cases of distant cutaneous metastases at atypical locations of prostate adenocarcinoma, and highlight the value of 2 immunohistochemical stains-prostatic acid phosphatase and prostate-specific membrane antigen-that can aid diagnosis, particularly in cases with negative staining for prostate-specific antigen. Copyright © 2016 AEDV. Publicado por Elsevier España, S.L.U. All rights reserved.

  4. Bell-state preparation for fullerene based electron spins in distant peapod nanotubes

    OpenAIRE

    Yang, W. L.; Wei, H; Zhang, X. L.; Feng, M.

    2008-01-01

    We propose a potentially practical scheme, in combination with the Bell-state analyzer [Zhang et al., Phys. Rev. A 73, 014301 (2006)], to generate Bell states for two electron spins confined, respectively, in two distant fullerenes. To this end, we consider the endohedral fullerenes staying in single walled carbon nanotubes (SWCNTs) and employ auxiliary mobile electrons and selective microwave pulses. The application and the experimental feasibility of our scheme are discussed.

  5. Immunohistochemical markers of distant metastasis in laryngeal and hypopharyngeal squamous cell carcinomas.

    Science.gov (United States)

    Rodrigo, Juan P; Martínez, Patricia; Allonca, Eva; Alonso-Durán, Laura; Suárez, Carlos; Astudillo, Aurora; García-Pedrero, Juana María

    2014-03-01

    Metastasis remains a major cause of mortality in head and neck squamous cell carcinoma (HNSCC). Current clinicopathological features have shown limited predictability for the risk of distant metastasis in individual patients, and therefore more accurate and reliable markers are needed. The aim of this study was to investigate the ability of various molecular markers present in primary tumors to predict the risk of developing distant metastasis. Restrictive clinical criteria were applied for patient selection in order to carry out a case-control study with comparable clinical features on a group-wide basis and a similar risk of metastasis. All patients were surgically treated (with postoperative radiotherapy when appropriate) and classified as stage IV disease. Immunohistochemical analysis was performed for a panel of proteins known to participate in cellular processes relevant to metastatic dissemination (E-cadherin, annexin A2, cortactin, FAK, EGFR, p53, and p-AKT). Results showed that the loss of E-cadherin expression was significantly correlated with the risk of distant metastasis (P = 0.002; log-rank test), while the loss of annexin A2 expression was nearly statistically significant (P = 0.06). None of the other protein markers assessed were associated with the development of distant metastasis. Therefore, according to our data the loss of epithelial adhesion seems to play a central role in the development of metastasis in HNSCC, and more importantly, immunohistochemical assessment of key proteins involved in cell adhesion regulation, such as E-cadherin could represent a useful tool to evaluate easily and routinely the metastatic potential of these carcinomas.

  6. Validation of the 18-gene classifier as a prognostic biomarker of distant metastasis in breast cancer.

    Science.gov (United States)

    Cheng, Skye Hung-Chun; Huang, Tzu-Ting; Cheng, Yu-Hao; Tan, Tee Benita Kiat; Horng, Chen-Fang; Wang, Yong Alison; Brian, Nicholas Shannon; Shih, Li-Sun; Yu, Ben-Long

    2017-01-01

    We validated an 18-gene classifier (GC) initially developed to predict local/regional recurrence after mastectomy in estimating distant metastasis risk. The 18-gene scoring algorithm defines scores as: breast cancer and fresh frozen tumor tissues available were included. The primary outcome was the 5-year probability of freedom from distant metastasis (DMFP). Two external datasets were used to test the predictive accuracy of 18-GC. The 5-year rates of DMFP for patients classified as low-risk (n = 146, 21.7%) and high-risk (n = 537, 78.6%) were 96.2% (95% CI, 91.1%-98.8%) and 80.9% (74.6%-81.9%), respectively (median follow-up interval, 71.8 months). The 5-year rates of DMFP of the low-risk group in stage I (n = 62, 35.6%), stage II (n = 66, 20.1%), and stage III (n = 18, 10.3%) were 100%, 94.2% (78.5%-98.5%), and 90.9% (50.8%-98.7%), respectively. Multivariate analysis revealed that 18-GC is an independent prognostic factor of distant metastasis (adjusted hazard ratio, 5.1; 95% CI, 1.8-14.1; p = 0.0017) for scores of ≥21. External validation showed that the 5-year rate of DMFP in the low- and high-risk patients was 94.1% (82.9%-100%) and 80.3% (70.7%-89.9%, p = 0.06) in a Singapore dataset, and 89.5% (81.9%-94.1%) and 73.6% (67.2%-79.0%, p = 0.0039) in the GEO-GSE20685 dataset, respectively. In conclusion, 18-GC is a viable prognostic biomarker for breast cancer to estimate distant metastasis risk.

  7. A simple solution of the twin paradox also shows anomalous behaviour of rigidly connected distant clocks

    Science.gov (United States)

    Singh Soni, Vidwan

    2002-03-01

    Although it has even been experimentally confirmed that the twin who travels away and comes back will age less, a conceptually very convincing theoretical treatment of the problem is still awaited. This paper presents a very simple solution of the twin paradox based on special relativity which proves from the viewpoint of the traveller twin also that he or she ages less. But with that, an anomalous behaviour of rigidly connected distant clocks is also observed.

  8. Nomograms to predict isolated loco-regional or distant recurrence among women with uterine cancer.

    Science.gov (United States)

    Kondalsamy-Chennakesavan, Srinivas; Yu, Changhong; Kattan, Michael W; Leung, Yee; Sykes, Peter; Nascimento, Marcelo; Nicklin, James; Perrin, Lewis; Crandon, Alex; Chetty, Naven; Land, Russell; Garrett, Andrea; Obermair, Andreas

    2012-06-01

    While there is ample literature on prognostic factors for uterine cancer, currently there are nomeans to estimate an individual's risk for recurrence or to differentiate the risk of loco-regional recurrence from distant recurrence. We addressed this gap by developing nomograms to individualize the risk of recurrence. A total of 2097 consecutive patients who underwent primary surgery between 1997 and 2007 were included. Sixteen covariates were evaluated for their prognostic significance and modeled using multivariable competing risks regression to predict three-year outcomes as part of a nomogram. Each covariate in the nomogram is assigned a value, and a sum of these values form the overall risk score from which three-year incidence probabilities can be predicted for each individual. Predictive accuracy was assessed with concordance index and then corrected for optimism. The median follow-up time (inter-quartile range, IQR) was 50.0 (28.3-77.5) months and 221 patients developed a recurrence (127 patients with isolated loco-regional recurrence, 94 patients with distant recurrence). The nomograms included the following covariates: age at diagnosis, FIGO stage (2009), grade, lymphovascular invasion, histological type, depth of myometrial invasion, and peritoneal cytology. Concordance indices for isolated loco-regional and distant recurrences were 0.73 and 0.86, respectively. Our nomograms quantify an individual patient's risk of isolated loco-regional and distant recurrence, using factors that are routinely collected. They may assist clinicians to assess an individual's prognosis, individualize treatment and also assist in the risk stratification in prospective randomized clinical trials evaluating the effectiveness of treatments for uterine cancer. Copyright © 2012 Elsevier Inc. All rights reserved.

  9. The Evolutionary Puzzle of Suicide

    Directory of Open Access Journals (Sweden)

    Henri-Jean Aubin

    2013-12-01

    Full Text Available Mechanisms of self-destruction are difficult to reconcile with evolution’s first rule of thumb: survive and reproduce. However, evolutionary success ultimately depends on inclusive fitness. The altruistic suicide hypothesis posits that the presence of low reproductive potential and burdensomeness toward kin can increase the inclusive fitness payoff of self-removal. The bargaining hypothesis assumes that suicide attempts could function as an honest signal of need. The payoff may be positive if the suicidal person has a low reproductive potential. The parasite manipulation hypothesis is founded on the rodent—Toxoplasma gondii host-parasite model, in which the parasite induces a “suicidal” feline attraction that allows the parasite to complete its life cycle. Interestingly, latent infection by T. gondii has been shown to cause behavioral alterations in humans, including increased suicide attempts. Finally, we discuss how suicide risk factors can be understood as nonadaptive byproducts of evolved mechanisms that malfunction. Although most of the mechanisms proposed in this article are largely speculative, the hypotheses that we raise accept self-destructive behavior within the framework of evolutionary theory.

  10. Language as an evolutionary system

    Science.gov (United States)

    Brighton, Henry; Smith, Kenny; Kirby, Simon

    2005-09-01

    John Maynard Smith and Eörs Szathmáry argued that human language signified the eighth major transition in evolution: human language marked a new form of information transmission from one generation to another [Maynard Smith J, Szathmáry E. The major transitions in evolution. Oxford: Oxford Univ. Press; 1995]. According to this view language codes cultural information and as such forms the basis for the evolution of complexity in human culture. In this article we develop the theory that language also codes information in another sense: languages code information on their own structure. As a result, languages themselves provide information that influences their own survival. To understand the consequences of this theory we discuss recent computational models of linguistic evolution. Linguistic evolution is the process by which languages themselves evolve. This article draws together this recent work on linguistic evolution and highlights the significance of this process in understanding the evolution of linguistic complexity. Our conclusions are that: (1) the process of linguistic transmission constitutes the basis for an evolutionary system, and (2), that this evolutionary system is only superficially comparable to the process of biological evolution.

  11. Evolutionary potential games on lattices

    Energy Technology Data Exchange (ETDEWEB)

    Szabó, György, E-mail: szabo@mfa.kfki.hu; Borsos, István, E-mail: borsos@mfa.kfki.hu

    2016-04-05

    Game theory provides a general mathematical background to study the effect of pair interactions and evolutionary rules on the macroscopic behavior of multi-player games where players with a finite number of strategies may represent a wide scale of biological objects, human individuals, or even their associations. In these systems the interactions are characterized by matrices that can be decomposed into elementary matrices (games) and classified into four types. The concept of decomposition helps the identification of potential games and also the evaluation of the potential that plays a crucial role in the determination of the preferred Nash equilibrium, and defines the Boltzmann distribution towards which these systems evolve for suitable types of dynamical rules. This survey draws parallel between the potential games and the kinetic Ising type models which are investigated for a wide scale of connectivity structures. We discuss briefly the applicability of the tools and concepts of statistical physics and thermodynamics. Additionally the general features of ordering phenomena, phase transitions and slow relaxations are outlined and applied to evolutionary games. The discussion extends to games with three or more strategies. Finally we discuss what happens when the system is weakly driven out of the “equilibrium state” by adding non-potential components representing games of cyclic dominance.

  12. Evolutionary Biology Needs Wild Microbiomes.

    Science.gov (United States)

    Hird, Sarah M

    2017-01-01

    The microbiome is a vital component to the evolution of a host and much of what we know about the microbiome derives from studies on humans and captive animals. But captivity alters the microbiome and mammals have unique biological adaptations that affect their microbiomes (e.g., milk). Birds represent over 30% of known tetrapod diversity and possess their own suite of adaptations relevant to the microbiome. In a previous study, we showed that 59 species of birds displayed immense variation in their microbiomes and host (bird) taxonomy and ecology were most correlated with the gut microbiome. In this Frontiers Focused Review, I put those results in a broader context by discussing how collecting and analyzing wild microbiomes contributes to the main goals of evolutionary biology and the specific ways that birds are unique microbial hosts. Finally, I outline some of the methodological considerations for adding microbiome sampling to the research of wild animals and urge researchers to do so. To truly understand the evolution of a host, we need to understand the millions of microorganisms that inhabit it as well: evolutionary biology needs wild microbiomes.

  13. Evolutionary Models for Simple Biosystems

    Science.gov (United States)

    Bagnoli, Franco

    The concept of evolutionary development of structures constituted a real revolution in biology: it was possible to understand how the very complex structures of life can arise in an out-of-equilibrium system. The investigation of such systems has shown that indeed, systems under a flux of energy or matter can self-organize into complex patterns, think for instance to Rayleigh-Bernard convection, Liesegang rings, patterns formed by granular systems under shear. Following this line, one could characterize life as a state of matter, characterized by the slow, continuous process that we call evolution. In this paper we try to identify the organizational level of life, that spans several orders of magnitude from the elementary constituents to whole ecosystems. Although similar structures can be found in other contexts like ideas (memes) in neural systems and self-replicating elements (computer viruses, worms, etc.) in computer systems, we shall concentrate on biological evolutionary structure, and try to put into evidence the role and the emergence of network structure in such systems.

  14. Evolutionary development of tensegrity structures.

    Science.gov (United States)

    Lobo, Daniel; Vico, Francisco J

    2010-09-01

    Contributions from the emerging fields of molecular genetics and evo-devo (evolutionary developmental biology) are greatly benefiting the field of evolutionary computation, initiating a promise of renewal in the traditional methodology. While direct encoding has constituted a dominant paradigm, indirect ways to encode the solutions have been reported, yet little attention has been paid to the benefits of the proposed methods to real problems. In this work, we study the biological properties that emerge by means of using indirect encodings in the context of form-finding problems. A novel indirect encoding model for artificial development has been defined and applied to an engineering structural-design problem, specifically to the discovery of tensegrity structures. This model has been compared with a direct encoding scheme. While the direct encoding performs similarly well to the proposed method, indirect-based results typically outperform the direct-based results in aspects not directly linked to the nature of the problem itself, but to the emergence of properties found in biological organisms, like organicity, generalization capacity, or modularity aspects which are highly valuable in engineering. Copyright 2010 Elsevier Ireland Ltd. All rights reserved.

  15. Multiple Distant Origins for Green Sea Turtles Aggregating off Gorgona Island in the Colombian Eastern Pacific

    Science.gov (United States)

    Amorocho, Diego F.; Abreu-Grobois, F. Alberto; Dutton, Peter H.; Reina, Richard D.

    2012-01-01

    Mitochondrial DNA analyses have been useful for resolving maternal lineages and migratory behavior to foraging grounds (FG) in sea turtles. However, little is known about source rookeries and haplotype composition of foraging green turtle aggregations in the southeastern Pacific. We used mitochondrial DNA control region sequences to identify the haplotype composition of 55 green turtles, Chelonia mydas, captured in foraging grounds of Gorgona National Park in the Colombian Pacific. Amplified fragments of the control region (457 bp) revealed the presence of seven haplotypes, with haplotype (h) and nucleotide (π) diversities of h = 0.300±0.080 and π = 0.009±0.005 respectively. The most common haplotype was CMP4 observed in 83% of individuals, followed by CMP22 (5%). The genetic composition of the Gorgona foraging population primarily comprised haplotypes that have been found at eastern Pacific rookeries including Mexico and the Galapagos, as well as haplotypes of unknown stock origin that likely originated from more distant western Pacific rookeries. Mixed stock analysis suggests that the Gorgona FG population is comprised mostly of animals from the Galapagos rookery (80%). Lagrangian drifter data showed that movement of turtles along the eastern Pacific coast and eastward from distant western and central Pacific sites was possible through passive drift. Our results highlight the importance of this protected area for conservation management of green turtles recruited from distant sites along the eastern Pacific Ocean. PMID:22319635

  16. Prediction of residual disease or distant metastasis after resection of locally recurrent rectal cancer.

    Science.gov (United States)

    Kanemitsu, Yukihide; Hirai, Takashi; Komori, Koji; Kato, Tomoyuki

    2010-05-01

    It is important to preoperatively identify patients at high risk of relapse at extrapelvic sites or residual disease after salvage surgery for locally recurrent rectal cancer to maximize the survival benefit by indicating whether a surgical approach might be successful. Data from 101 consecutive patients who underwent exploration with curative intent for local recurrence after radical resection of rectal cancer were retrospectively collected. Preoperative factors were examined in univariate and multivariate analyses for their ability to predict resectability and distant disease-free survival. The 5-year disease-specific survival rates of R0, R1, and R2 resection were 43.3%, 19.5%, and 10.0%, respectively (P sacrum)/lateral invasive type and high-grade lymphatic invasion of the primary tumor were associated with palliative surgery. A Cox regression analysis revealed that upper sacral/lateral invasive type, extrapelvic disease, hydronephrosis at recurrence, and high-grade lymphatic or venous invasion of the primary tumor were associated with a lower distant disease-free survival rate. Patients with one or more of these risk factors had a 3-year distant disease-free survival rate of 6.2% compared with 54.1% for those with none of these risk factors. It was possible to preoperatively identify patients at high risk of relapse or residual disease. This system might be used on an individual basis to select patients with locally recurrent rectal cancer for chemotherapy or radiotherapy before surgical intervention with curative intent.

  17. Multi-objective radiomics model for predicting distant failure in lung SBRT

    Science.gov (United States)

    Zhou, Zhiguo; Folkert, Michael; Iyengar, Puneeth; Westover, Kenneth; Zhang, Yuanyuan; Choy, Hak; Timmerman, Robert; Jiang, Steve; Wang, Jing

    2017-06-01

    Stereotactic body radiation therapy (SBRT) has demonstrated high local control rates in early stage non-small cell lung cancer patients who are not ideal surgical candidates. However, distant failure after SBRT is still common. For patients at high risk of early distant failure after SBRT treatment, additional systemic therapy may reduce the risk of distant relapse and improve overall survival. Therefore, a strategy that can correctly stratify patients at high risk of failure is needed. The field of radiomics holds great potential in predicting treatment outcomes by using high-throughput extraction of quantitative imaging features. The construction of predictive models in radiomics is typically based on a single objective such as overall accuracy or the area under the curve (AUC). However, because of imbalanced positive and negative events in the training datasets, a single objective may not be ideal to guide model construction. To overcome these limitations, we propose a multi-objective radiomics model that simultaneously considers sensitivity and specificity as objective functions. To design a more accurate and reliable model, an iterative multi-objective immune algorithm (IMIA) was proposed to optimize these objective functions. The multi-objective radiomics model is more sensitive than the single-objective model, while maintaining the same levels of specificity and AUC. The IMIA performs better than the traditional immune-inspired multi-objective algorithm.

  18. Diagnosis of Distant Metastasis of Lung Cancer: Based on Clinical and Radiomic Features

    Directory of Open Access Journals (Sweden)

    Hongyu Zhou

    2018-02-01

    Full Text Available OBJECTIVES: To analyze the distant metastasis possibility based on computed tomography (CT radiomic features in patients with lung cancer. METHODS: This was a retrospective analysis of 348 patients with lung cancer enrolled between 2014 and February 2015. A feature set containing clinical features and 485 radiomic features was extracted from the pretherapy CT images. Feature selection via concave minimization (FSV was used to select effective features. A support vector machine (SVM was used to evaluate the predictive ability of each feature. RESULTS: Four radiomic features and three clinical features were obtained by FSV feature selection. Classification accuracy by the proposed SVM with SGD method was 71.02%, and the area under the curve was 72.84% with only the radiomic features extracted from CT. After the addition of clinical features, 89.09% can be achieved. CONCLUSION: The radiomic features of the pretherapy CT images may be used as predictors of distant metastasis. And it also can be used in combination with the patient's gender and tumor T and N phase information to diagnose the possibility of distant metastasis in lung cancer.

  19. Cost of wind energy: comparing distant wind resources to local resources in the midwestern United States.

    Science.gov (United States)

    Hoppock, David C; Patiño-Echeverri, Dalia

    2010-11-15

    The best wind sites in the United States are often located far from electricity demand centers and lack transmission access. Local sites that have lower quality wind resources but do not require as much power transmission capacity are an alternative to distant wind resources. In this paper, we explore the trade-offs between developing new wind generation at local sites and installing wind farms at remote sites. We first examine the general relationship between the high capital costs required for local wind development and the relatively lower capital costs required to install a wind farm capable of generating the same electrical output at a remote site,with the results representing the maximum amount an investor should be willing to pay for transmission access. We suggest that this analysis can be used as a first step in comparing potential wind resources to meet a state renewable portfolio standard (RPS). To illustrate, we compare the cost of local wind (∼50 km from the load) to the cost of distant wind requiring new transmission (∼550-750 km from the load) to meet the Illinois RPS. We find that local, lower capacity factor wind sites are the lowest cost option for meeting the Illinois RPS if new long distance transmission is required to access distant, higher capacity factor wind resources. If higher capacity wind sites can be connected to the existing grid at minimal cost, in many cases they will have lower costs.

  20. Extracting PICO Sentences from Clinical Trial Reports using Supervised Distant Supervision.

    Science.gov (United States)

    Wallace, Byron C; Kuiper, Joël; Sharma, Aakash; Zhu, Mingxi Brian; Marshall, Iain J

    2016-01-01

    Systematic reviews underpin Evidence Based Medicine (EBM) by addressing precise clinical questions via comprehensive synthesis of all relevant published evidence. Authors of systematic reviews typically define a Population/Problem, Intervention, Comparator, and Outcome (a PICO criteria) of interest, and then retrieve, appraise and synthesize results from all reports of clinical trials that meet these criteria. Identifying PICO elements in the full-texts of trial reports is thus a critical yet time-consuming step in the systematic review process. We seek to expedite evidence synthesis by developing machine learning models to automatically extract sentences from articles relevant to PICO elements. Collecting a large corpus of training data for this task would be prohibitively expensive. Therefore, we derive distant supervision (DS) with which to train models using previously conducted reviews. DS entails heuristically deriving 'soft' labels from an available structured resource. However, we have access only to unstructured, free-text summaries of PICO elements for corresponding articles; we must derive from these the desired sentence-level annotations. To this end, we propose a novel method - supervised distant supervision (SDS) - that uses a small amount of direct supervision to better exploit a large corpus of distantly labeled instances by learning to pseudo-annotate articles using the available DS. We show that this approach tends to outperform existing methods with respect to automated PICO extraction.

  1. Looking into the Future: A Match between Self-View and Temporal Distance

    OpenAIRE

    Gerri Spassova; Angela Y Lee

    2013-01-01

    Representing an event in abstract (vs. concrete) terms and as happening in the distant (vs. proximal) future has been shown to have important consequences for cognition and motivation. Less is known about factors that influence construal level and perceived temporal distance. The present research identifies one such factor and explores the implications for persuasion. Four studies show that an independent self-view is associated with abstract representations of future events and with perceivi...

  2. Evolutionary multimodal optimization using the principle of locality

    KAUST Repository

    Wong, Kachun

    2012-07-01

    The principle of locality is one of the most widely used concepts in designing computing systems. To explore the principle in evolutionary computation, crowding differential evolution is incorporated with locality for multimodal optimization. Instead of generating trial vectors randomly, the first method proposed takes advantage of spatial locality to generate trial vectors. Temporal locality is also adopted to help generate offspring in the second method proposed. Temporal and spatial locality are then applied together in the third method proposed. Numerical experiments are conducted to compare the proposed methods with the state-of-the-art methods on benchmark functions. Experimental analysis is undertaken to observe the effect of locality and the synergy between temporal locality and spatial locality. Further experiments are also conducted on two application problems. One is the varied-line-spacing holographic grating design problem, while the other is the protein structure prediction problem. The numerical results demonstrate the effectiveness of the methods proposed. © 2012 Elsevier Inc. All rights reserved.

  3. Temporal attention as a Scaffold for Language Development

    Directory of Open Access Journals (Sweden)

    Ruth eDe Diego-Balaguer

    2016-02-01

    Full Text Available Language is one of the most fascinating abilities that humans possess. Infants demonstrate an amazing repertoire of linguistic abilities from very early on and reach an adult-like form incredibly fast. However, language is not acquired all at once but in an incremental fashion. In this article we propose that the attentional system may be one of the sources for this developmental trajectory in language acquisition. At birth, infants are endowed with an attentional system fully driven by salient stimuli in their environment, such as prosodic information (e.g., rhythm or pitch. Early stages of language acquisition could benefit from this readily available, stimulus-driven attention to simplify the complex speech input and allow word segmentation. At later stages of development, infants are progressively able to selectively attend to specific elements while disregarding others. This attentional ability could allow them to learn distant non-adjacent rules needed for morphosyntactic acquisition. Because non-adjacent dependencies occur at distant moments in time, learning these dependencies may require correctly orienting attention in the temporal domain. Here, we gather evidence uncovering the intimate relationship between the development of attention and language. We aim to provide a novel approach to human development, bridging together temporal attention and language acquisition.

  4. Evolutionary triangulation: informing genetic association studies with evolutionary evidence.

    Science.gov (United States)

    Huang, Minjun; Graham, Britney E; Zhang, Ge; Harder, Reed; Kodaman, Nuri; Moore, Jason H; Muglia, Louis; Williams, Scott M

    2016-01-01

    Genetic studies of human diseases have identified many variants associated with pathogenesis and severity. However, most studies have used only statistical association to assess putative relationships to disease, and ignored other factors for evaluation. For example, evolution is a factor that has shaped disease risk, changing allele frequencies as human populations migrated into and inhabited new environments. Since many common variants differ among populations in frequency, as does disease prevalence, we hypothesized that patterns of disease and population structure, taken together, will inform association studies. Thus, the population distributions of allelic risk variants should reflect the distributions of their associated diseases. Evolutionary Triangulation (ET) exploits this evolutionary differentiation by comparing population structure among three populations with variable patterns of disease prevalence. By selecting populations based on patterns where two have similar rates of disease that differ substantially from a third, we performed a proof of principle analysis for this method. We examined three disease phenotypes, lactase persistence, melanoma, and Type 2 diabetes mellitus. We show that for lactase persistence, a phenotype with a simple genetic architecture, ET identifies the key gene, lactase. For melanoma, ET identifies several genes associated with this disease and/or phenotypes related to it, such as skin color genes. ET was less obviously successful for Type 2 diabetes mellitus, perhaps because of the small effect sizes in known risk loci and recent environmental changes that have altered disease risk. Alternatively, ET may have revealed new genes involved in conferring disease risk for diabetes that did not meet nominal GWAS significance thresholds. We also compared ET to another method used to filter for phenotype associated genes, population branch statistic (PBS), and show that ET performs better in identifying genes known to associate with

  5. Distinguishing synchronous from metachronous manifestation of distant metastases: a prognostic feature in differentiated thyroid carcinoma

    Energy Technology Data Exchange (ETDEWEB)

    Sabet, Amir [University Duisburg-Essen, Department of Nuclear Medicine, Essen (Germany); Saarland University Hospital, Department of Nuclear Medicine, Homburg (Germany); Binse, Ina; Koch, Andrea; Rosenbaum-Krumme, Sandra J. [University Duisburg-Essen, Department of Nuclear Medicine, Essen (Germany); Dogan, Semih; Biersack, Hans-Juergen [University Hospital, Department of Nuclear Medicine, Bonn (Germany); Biermann, Kim [University Hospital, Department of Nuclear Medicine, Bonn (Germany); Confessional Hospital ' ' Barmherzige Brueder' ' , Department of Radiology and Nuclear Medicine, Trier (Germany); Ezziddin, Samer [Saarland University Hospital, Department of Nuclear Medicine, Homburg (Germany); University Hospital, Department of Nuclear Medicine, Bonn (Germany)

    2017-02-15

    Distant metastasis has a negative impact on survival in differentiated thyroid carcinoma (DTC). The timing of this manifestation, however, is of unknown prognostic relevance. The aim of this retrospective study was to investigate the potential significance of discriminating synchronous versus metachronous distant metastases (SDM vs. MDM) for the outcome of patients with DTC. We retrospectively analyzed a consecutive cohort of n = 89 patients with distant metastases of DTC (43 with follicular, 46 with papillary DTC histology; mean age 52.6 ± 17.7 years) undergoing radioiodine treatment at our institution. All patients were treated with the same protocol consisting of ablative radioiodine therapy (RIT, 3.7 GBq) and one post-ablation treatment after 3 months (3.7-11.1 GBq). Further cycles of RIT were administered for recurrent, progressive or newly developed metastatic disease. We distinguished 2 types of distant metastases according to the time of manifestation: SDM (within ≤12 months after DTC diagnosis) and MDM (occurring >12 months after diagnosis). Tumor-related survival was analyzed using the Kaplan-Meier method. Uni- and multivariate analyses including the Cox proportional hazards model were performed with a significance level of p < 0.05. The mean follow-up period was 13.8 ± 1.2 years. SDM were present in 49 (55.1 %), MDM in 40 (44.9 %) patients. MDM were associated with shorter tumor-related survival (p = 0.002). 5-year and 10-year survival rates were 68.5 % and 34.8 % for MDM, and 84.3 % and 66.9 % for SDM, respectively. Within both age subgroups of <45 and ≥45 years, SDM were also linked with longer survival. No effect on tumor-related survival was found for the co-variables sex, lymph node metastases and histologic type. Distinguishing synchronous from metachronous manifestation of distant metastases may add an important prognostic feature to risk stratification in DTC, as proven metachronous appearance is associated with impaired survival. (orig.)

  6. Data from selective harvests underestimate temporal trends in quantitative traits.

    Science.gov (United States)

    Pelletier, Fanie; Festa-Bianchet, Marco; Jorgenson, Jon T

    2012-10-23

    Human harvests can select against phenotypes favoured by natural selection, and natural resource managers should evaluate possible artificial selection on wild populations. Because the required genetic data are extremely difficult to gather, however, managers typically rely on harvested animals to document temporal trends. It is usually unknown whether these data are unbiased. We explore our ability to detect a decline in horn size of bighorn sheep (Ovis canadensis) by comparing harvested males with all males in a population where evolutionary changes owing to trophy hunting were previously reported. Hunting records underestimated the temporal decline, partly because of an increasing proportion of rams that could not be harvested because their horns were smaller than the threshold set by hunting regulations. If harvests are selective, temporal trends measured from harvest records will underestimate the magnitude of changes in wild populations.

  7. Anthropology and the study of menopause: evolutionary, developmental, and comparative perspectives.

    Science.gov (United States)

    Sievert, Lynnette Leidy

    2014-10-01

    This work aims to consider how the discipline of anthropology contributes to the study of menopause through evolutionary, developmental, and comparative perspectives. This study was a review of skeletal and ethnographic evidence for menopause and postreproductive life in humans' distant past, hypotheses for the evolution of menopause and long postreproductive life, variation in age at menopause with focus on childhood environments, and the study of variation in symptom experience across populations. Longevity, rather than capacity for menopause, sets humans apart from other primates. Skeletal evidence demonstrates that some Neanderthals and archaic Homo sapiens lived to the age at menopause and that at least one third of women in traditional foraging populations live beyond menopause. The evolutionary reasons for why women experience a long postreproductive life continue to be debated. A developmental perspective suggests that early childhood may be a critical time for the environment to irreversibly influence the number of oocytes or rate of follicular atresia and, ultimately, age at menopause. A comparative perspective examines symptom experience at midlife through participant observation, qualitative interviews, and quantitative instruments to gain a holistic understanding of the meaning, experience, and sociocultural context of menopause. An evolutionary perspective suggests that menopause is not a recent phenomenon among humans. A developmental perspective focuses on the influence of early childhood on ovarian function. A comparative perspective expands clinical norms and provides knowledge about the range of human variations.

  8. Scalable computing for evolutionary genomics.

    Science.gov (United States)

    Prins, Pjotr; Belhachemi, Dominique; Möller, Steffen; Smant, Geert

    2012-01-01

    Genomic data analysis in evolutionary biology is becoming so computationally intensive that analysis of multiple hypotheses and scenarios takes too long on a single desktop computer. In this chapter, we discuss techniques for scaling computations through parallelization of calculations, after giving a quick overview of advanced programming techniques. Unfortunately, parallel programming is difficult and requires special software design. The alternative, especially attractive for legacy software, is to introduce poor man's parallelization by running whole programs in parallel as separate processes, using job schedulers. Such pipelines are often deployed on bioinformatics computer clusters. Recent advances in PC virtualization have made it possible to run a full computer operating system, with all of its installed software, on top of another operating system, inside a "box," or virtual machine (VM). Such a VM can flexibly be deployed on multiple computers, in a local network, e.g., on existing desktop PCs, and even in the Cloud, to create a "virtual" computer cluster. Many bioinformatics applications in evolutionary biology can be run in parallel, running processes in one or more VMs. Here, we show how a ready-made bioinformatics VM image, named BioNode, effectively creates a computing cluster, and pipeline, in a few steps. This allows researchers to scale-up computations from their desktop, using available hardware, anytime it is required. BioNode is based on Debian Linux and can run on networked PCs and in the Cloud. Over 200 bioinformatics and statistical software packages, of interest to evolutionary biology, are included, such as PAML, Muscle, MAFFT, MrBayes, and BLAST. Most of these software packages are maintained through the Debian Med project. In addition, BioNode contains convenient configuration scripts for parallelizing bioinformatics software. Where Debian Med encourages packaging free and open source bioinformatics software through one central project

  9. Markov Networks in Evolutionary Computation

    CERN Document Server

    Shakya, Siddhartha

    2012-01-01

    Markov networks and other probabilistic graphical modes have recently received an upsurge in attention from Evolutionary computation community, particularly in the area of Estimation of distribution algorithms (EDAs).  EDAs have arisen as one of the most successful experiences in the application of machine learning methods in optimization, mainly due to their efficiency to solve complex real-world optimization problems and their suitability for theoretical analysis. This book focuses on the different steps involved in the conception, implementation and application of EDAs that use Markov networks, and undirected models in general. It can serve as a general introduction to EDAs but covers also an important current void in the study of these algorithms by explaining the specificities and benefits of modeling optimization problems by means of undirected probabilistic models. All major developments to date in the progressive introduction of Markov networks based EDAs are reviewed in the book. Hot current researc...

  10. Evolutionary Games and Social Conventions

    DEFF Research Database (Denmark)

    Hansen, Pelle Guldborg

    2007-01-01

    Some thirty years ago Lewis published his Convention: A Philosophical Study (Lewis, 2002). This laid the foundation for a game-theoretic approach to social conventions, but became more famously known for its seminal analysis of common knowledge; the concept receiving its canonical analysis...... in Aumann (1976) and which, together with the assumptions of perfect rationality, came to be defining of classical game theory. However, classical game theory is currently undergoing severe crisis as a tool for exploring social phenomena; a crisis emerging from the problem of equilibrium selection around......-defined metaphors of individual learning and social imitation processes, from which a revised theory of convention may be erected (see Sugden 2004, Binmore 1993 and Young 1998). This paper makes a general argument in support of the evolutionary turn in the theory of convention by a progressive exposition of its...

  11. Steps towards an evolutionary physics

    CERN Document Server

    Tiezzi, E

    2006-01-01

    If thermodynamics is to physics as logic is to philosophy, recent theoretical advancements lend new coherence to the marvel and dynamism of life on Earth. Enzo Tiezzi's "Steps Towards an Evolutionary Physics" is a primer and guide, to those who would to stand on the shoulders of giants to attain this view: Heisenberg, Planck, Bateson, Varela, and Prigogine as well as notable contemporary scientists. The adventure of such a free and enquiring spirit thrives not so much on answers as on new questions. The book offers a new gestalt on the uncertainty principle and concept of probability. A wide range of examples, enigmas, and paradoxes lead one's imagination on an exquisite dance. Among the applications are: songs and shapes of nature, oscillatory reactions, orientors, goal functions and configurations of processes, and "dissipative structures and the city". Ecodynamics is a new science, which proposes a cross-fertilization between Charles Darwin and Ilya Prigogine. As an enigma in thermodynamics, Entropy forms ...

  12. Piaget, Pedagogy, and Evolutionary Psychology

    Directory of Open Access Journals (Sweden)

    Jeremy E. C. Genovese

    2003-01-01

    Full Text Available Constructivist pedagogy draws on Piaget's developmental theory. Because Piaget depicted the emergence of formal reasoning skills in adolescence as part of the normal developmental pattern, many constructivists have assumed that intrinsic motivation is possible for all academic tasks. This paper argues that Piaget's concept of a formal operational stage has not been empirically verified and that the cognitive skills associated with that stage are in fact “biologically secondary abilities” (Geary and Bjorklund, 2000 culturally determined abilities that are difficult to acquire. Thus, it is unreasonable to expect that intrinsic motivation will suffice for most students for most higher level academic tasks. In addition, a case is made that educational psychology must incorporate the insights of evolutionary psychology.

  13. Evolutionary origin of insect pheromones.

    Science.gov (United States)

    Stökl, Johannes; Steiger, Sandra

    2017-12-01

    Communication via chemical signals, that is, pheromones, is of pivotal importance for most insects. According to current evolutionary theory, insect pheromones originated either from extant precursor compounds being selected for information transfer or by the pheromone components exploiting a pre-existing sensory bias in the receiver. Here, we review the available experimental evidence for both hypotheses. Existing data indicate that most insect pheromones evolved from precursor compounds that were emitted as metabolic by-products or that previously had other non-communicative functions. Many studies have investigated cuticular hydrocarbons that have evolved a communicative function, although examples of pheromones exist that have arisen from defensive secretions, hormones or dietary compounds. We summarize and discuss the selective pressures shaping the pheromone during signal evolution. Copyright © 2017 Elsevier Inc. All rights reserved.

  14. Quantum Mechanics predicts evolutionary biology.

    Science.gov (United States)

    Torday, J S

    2018-01-11

    Nowhere are the shortcomings of conventional descriptive biology more evident than in the literature on Quantum Biology. In the on-going effort to apply Quantum Mechanics to evolutionary biology, merging Quantum Mechanics with the fundamentals of evolution as the First Principles of Physiology-namely negentropy, chemiosmosis and homeostasis-offers an authentic opportunity to understand how and why physics constitutes the basic principles of biology. Negentropy and chemiosmosis confer determinism on the unicell, whereas homeostasis constitutes Free Will because it offers a probabilistic range of physiologic set points. Similarly, on this basis several principles of Quantum Mechanics also apply directly to biology. The Pauli Exclusion Principle is both deterministic and probabilistic, whereas non-localization and the Heisenberg Uncertainty Principle are both probabilistic, providing the long-sought after ontologic and causal continuum from physics to biology and evolution as the holistic integration recognized as consciousness for the first time. Copyright © 2018. Published by Elsevier Ltd.

  15. Evolutionary Inspection and Corruption Games

    Directory of Open Access Journals (Sweden)

    Stamatios Katsikas

    2016-10-01

    Full Text Available We extend a standard two-person, non-cooperative, non-zero sum, imperfect inspection game, considering a large population of interacting inspectees and a single inspector. Each inspectee adopts one strategy, within a finite/infinite bounded set of strategies returning increasingly illegal profits, including compliance. The inspectees may periodically update their strategies after randomly inter-comparing the obtained payoffs, setting their collective behaviour subject to evolutionary pressure. The inspector decides, at each update period, the optimum fraction of his/her renewable budget to invest on his/her interference with the inspectees’ collective effect. To deter the inspectees from violating, he/she assigns a fine to each illegal strategy. We formulate the game mathematically, study its dynamics and predict its evolution subject to two key controls, the inspection budget and the punishment fine. Introducing a simple linguistic twist, we also capture the corresponding version of a corruption game.

  16. Numerical and Evolutionary Optimization Workshop

    CERN Document Server

    Trujillo, Leonardo; Legrand, Pierrick; Maldonado, Yazmin

    2017-01-01

    This volume comprises a selection of works presented at the Numerical and Evolutionary Optimization (NEO) workshop held in September 2015 in Tijuana, Mexico. The development of powerful search and optimization techniques is of great importance in today’s world that requires researchers and practitioners to tackle a growing number of challenging real-world problems. In particular, there are two well-established and widely known fields that are commonly applied in this area: (i) traditional numerical optimization techniques and (ii) comparatively recent bio-inspired heuristics. Both paradigms have their unique strengths and weaknesses, allowing them to solve some challenging problems while still failing in others. The goal of the NEO workshop series is to bring together people from these and related fields to discuss, compare and merge their complimentary perspectives in order to develop fast and reliable hybrid methods that maximize the strengths and minimize the weaknesses of the underlying paradigms. Throu...

  17. Bacterial Actins? An Evolutionary Perspective

    Science.gov (United States)

    Doolittle, Russell F.; York, Amanda L.

    2003-01-01

    According to the conventional wisdom, the existence of a cytoskeleton in eukaryotes and its absence in prokaryotes constitute a fundamental divide between the two domains of life. An integral part of the dogma is that a cytoskeleton enabled an early eukaryote to feed upon prokaryotes, a consequence of which was the occasional endosymbiosis and the eventual evolution of organelles. Two recent papers present compelling evidence that actin, one of the principal components of a cytoskeleton, has a homolog in Bacteria that behaves in many ways like eukaryotic actin. Sequence comparisons reveml that eukaryotic actin and the bacterial homolog (mreB protein), unlike many other proteins common to eukaryotes and Bacteria, have very different and more highly extended evolutionary histories.

  18. Algorithmic Mechanism Design of Evolutionary Computation.

    Science.gov (United States)

    Pei, Yan

    2015-01-01

    We consider algorithmic design, enhancement, and improvement of evolutionary computation as a mechanism design problem. All individuals or several groups of individuals can be considered as self-interested agents. The individuals in evolutionary computation can manipulate parameter settings and operations by satisfying their own preferences, which are defined by an evolutionary computation algorithm designer, rather than by following a fixed algorithm rule. Evolutionary computation algorithm designers or self-adaptive methods should construct proper rules and mechanisms for all agents (individuals) to conduct their evolution behaviour correctly in order to definitely achieve the desired and preset objective(s). As a case study, we propose a formal framework on parameter setting, strategy selection, and algorithmic design of evolutionary computation by considering the Nash strategy equilibrium of a mechanism design in the search process. The evaluation results present the efficiency of the framework. This primary principle can be implemented in any evolutionary computation algorithm that needs to consider strategy selection issues in its optimization process. The final objective of our work is to solve evolutionary computation design as an algorithmic mechanism design problem and establish its fundamental aspect by taking this perspective. This paper is the first step towards achieving this objective by implementing a strategy equilibrium solution (such as Nash equilibrium) in evolutionary computation algorithm.

  19. Investigating Evolutionary Dynamics of RHA1 Operons

    OpenAIRE

    Yong Chen; Dandan Geng; Kristina Ehrhardt; Shaoqiang Zhang

    2016-01-01

    Grouping genes as operons is an important genomic feature of prokaryotic organisms. The comprehensive understanding of the operon organizations would be helpful to decipher transcriptional mechanisms, cellular pathways, and the evolutionary landscape of prokaryotic genomes. Although thousands of prokaryotes have been sequenced, genome-wide investigation of the evolutionary dynamics (division and recombination) of operons among these genomes remains unexplored. Here, we systematically analyzed...

  20. Evolutionary principles and their practical application

    DEFF Research Database (Denmark)

    Hendry, A. P.; Kinnison, M. T.; Heino, M.

    2011-01-01

    Evolutionary principles are now routinely incorporated into medicine and agriculture. Examples include the design of treatments that slow the evolution of resistance by weeds, pests, and pathogens, and the design of breeding programs that maximize crop yield or quality. Evolutionary principles ar...

  1. Handbook of differential equations evolutionary equations

    CERN Document Server

    Dafermos, CM

    2008-01-01

    The material collected in this volume discusses the present as well as expected future directions of development of the field with particular emphasis on applications. The seven survey articles present different topics in Evolutionary PDE's, written by leading experts.- Review of new results in the area- Continuation of previous volumes in the handbook series covering Evolutionary PDEs- Written by leading experts

  2. On the Evolutionary Stability of Bargaining Inefficiency

    DEFF Research Database (Denmark)

    Poulsen, Anders

    This paper investigates whether 'tough' bargaining behavior, which gives rise to inefficiency, can be evolutionary stable. We show that in a two-stage Nash Demand Game tough behavior survives. Indeed, almost all the surplus may be wasted. We also study the Ultimatum Game. Here evolutionary...

  3. Evolutionary Biology in the Medical School Curriculum.

    Science.gov (United States)

    Neese, Randolph M.; Schiffman, Joshua D.

    2003-01-01

    Presents a study in which a questionnaire was given to deans at North American medical schools to determine which aspects of evolutionary biology are included in the curricula and the factors that influence this. Suggests that most future physicians should learn evolutionary biology as undergraduates if they are to learn it at all. (Author/NB)

  4. Evolutionary principles and their practical application.

    Science.gov (United States)

    Hendry, Andrew P; Kinnison, Michael T; Heino, Mikko; Day, Troy; Smith, Thomas B; Fitt, Gary; Bergstrom, Carl T; Oakeshott, John; Jørgensen, Peter S; Zalucki, Myron P; Gilchrist, George; Southerton, Simon; Sih, Andrew; Strauss, Sharon; Denison, Robert F; Carroll, Scott P

    2011-03-01

    Evolutionary principles are now routinely incorporated into medicine and agriculture. Examples include the design of treatments that slow the evolution of resistance by weeds, pests, and pathogens, and the design of breeding programs that maximize crop yield or quality. Evolutionary principles are also increasingly incorporated into conservation biology, natural resource management, and environmental science. Examples include the protection of small and isolated populations from inbreeding depression, the identification of key traits involved in adaptation to climate change, the design of harvesting regimes that minimize unwanted life-history evolution, and the setting of conservation priorities based on populations, species, or communities that harbor the greatest evolutionary diversity and potential. The adoption of evolutionary principles has proceeded somewhat independently in these different fields, even though the underlying fundamental concepts are the same. We explore these fundamental concepts under four main themes: variation, selection, connectivity, and eco-evolutionary dynamics. Within each theme, we present several key evolutionary principles and illustrate their use in addressing applied problems. We hope that the resulting primer of evolutionary concepts and their practical utility helps to advance a unified multidisciplinary field of applied evolutionary biology.

  5. Democratizing evolutionary biology, lessons from insects

    DEFF Research Database (Denmark)

    Dunn, Robert Roberdeau; Beasley, DeAnna E.

    2016-01-01

    The engagement of the public in the scientific process is an old practice. Yet with recent advances in technology, the role of the citizen scientist in studying evolutionary processes has increased. Insects provide ideal models for understanding these evolutionary processes at large scales. This ...

  6. Oversimplifying Evolutionary Psychology Leads to Explanatory Gaps

    Science.gov (United States)

    Tate, Chuck; Ledbetter, Jay N.

    2010-01-01

    Comments on Evolutionary psychology: Controversies, questions, prospects, and limitations by Confer et al. They argued that SST cannot explain the existence of either homosexuality or suicide within the human species. We contend that a sufficiently nuanced evolutionary position has no difficulties explaining either phenomenon. Also in this…

  7. Temporal network epidemiology

    CERN Document Server

    Holme, Petter

    2017-01-01

    This book covers recent developments in epidemic process models and related data on temporally varying networks. It is widely recognized that contact networks are indispensable for describing, understanding, and intervening to stop the spread of infectious diseases in human and animal populations; “network epidemiology” is an umbrella term to describe this research field. More recently, contact networks have been recognized as being highly dynamic. This observation, also supported by an increasing amount of new data, has led to research on temporal networks, a rapidly growing area. Changes in network structure are often informed by epidemic (or other) dynamics, in which case they are referred to as adaptive networks. This volume gathers contributions by prominent authors working in temporal and adaptive network epidemiology, a field essential to understanding infectious diseases in real society.

  8. Evolutionary history of tissue kallikreins.

    Directory of Open Access Journals (Sweden)

    Athanasia Pavlopoulou

    Full Text Available The gene family of human kallikrein-related peptidases (KLKs encodes proteins with diverse and pleiotropic functions in normal physiology as well as in disease states. Currently, the most widely known KLK is KLK3 or prostate-specific antigen (PSA that has applications in clinical diagnosis and monitoring of prostate cancer. The KLK gene family encompasses the largest contiguous cluster of serine proteases in humans which is not interrupted by non-KLK genes. This exceptional and unique characteristic of KLKs makes them ideal for evolutionary studies aiming to infer the direction and timing of gene duplication events. Previous studies on the evolution of KLKs were restricted to mammals and the emergence of KLKs was suggested about 150 million years ago (mya. In order to elucidate the evolutionary history of KLKs, we performed comprehensive phylogenetic analyses of KLK homologous proteins in multiple genomes including those that have been completed recently. Interestingly, we were able to identify novel reptilian, avian and amphibian KLK members which allowed us to trace the emergence of KLKs 330 mya. We suggest that a series of duplication and mutation events gave rise to the KLK gene family. The prominent feature of the KLK family is that it consists of tandemly and uninterruptedly arrayed genes in all species under investigation. The chromosomal co-localization in a single cluster distinguishes KLKs from trypsin and other trypsin-like proteases which are spread in different genetic loci. All the defining features of the KLKs were further found to be conserved in the novel KLK protein sequences. The study of this unique family will further assist in selecting new model organisms for functional studies of proteolytic pathways involving KLKs.

  9. Evolutionary genomics of dog domestication.

    Science.gov (United States)

    Wayne, Robert K; vonHoldt, Bridgett M

    2012-02-01

    We review the underlying principles and tools used in genomic studies of domestic dogs aimed at understanding the genetic changes that have occurred during domestication. We show that there are two principle modes of evolution within dogs. One primary mode that accounts for much of the remarkable diversity of dog breeds is the fixation of discrete mutations of large effect in individual lineages that are then crossed to various breed groupings. This transfer of mutations across the dog evolutionary tree leads to the appearance of high phenotypic diversity that in actuality reflects a small number of major genes. A second mechanism causing diversification involves the selective breeding of dogs within distinct phenotypic or functional groups, which enhances specific group attributes such as heading or tracking. Such progressive selection leads to a distinct genetic structure in evolutionary trees such that functional and phenotypic groups cluster genetically. We trace the origin of the nuclear genome in dogs based on haplotype-sharing analyses between dogs and gray wolves and show that contrary to previous mtDNA analyses, the nuclear genome of dogs derives primarily from Middle Eastern or European wolves, a result more consistent with the archeological record. Sequencing analysis of the IGF1 gene, which has been the target of size selection in small breeds, further supports this conclusion. Finally, we discuss how a black coat color mutation that evolved in dogs has transformed North American gray wolf populations, providing a first example of a mutation that appeared under domestication and selectively swept through a wild relative.

  10. Evolutionary design assistants for architecture

    Directory of Open Access Journals (Sweden)

    N. Onur Sönmez

    2015-04-01

    Full Text Available In its parallel pursuit of an increased competitivity for design offices and more pleasurable and easier workflows for designers, artificial design intelligence is a technical, intellectual, and political challenge. While human-machine cooperation has become commonplace through Computer Aided Design (CAD tools, a more improved collaboration and better support appear possible only through an endeavor into a kind of artificial design intelligence, which is more sensitive to the human perception of affairs. Considered as part of the broader Computational Design studies, the research program of this quest can be called Artificial / Autonomous / Automated Design (AD. The current available level of Artificial Intelligence (AI for design is limited and a viable aim for current AD would be to develop design assistants that are capable of producing drafts for various design tasks. Thus, the overall aim of this thesis is the development of approaches, techniques, and tools towards artificial design assistants that offer a capability for generating drafts for sub-tasks within design processes. The main technology explored for this aim is Evolutionary Computation (EC, and the target design domain is architecture. The two connected research questions of the study concern, first, the investigation of the ways to develop an architectural design assistant, and secondly, the utilization of EC for the development of such assistants. While developing approaches, techniques, and computational tools for such an assistant, the study also carries out a broad theoretical investigation into the main problems, challenges, and requirements towards such assistants on a rather overall level. Therefore, the research is shaped as a parallel investigation of three main threads interwoven along several levels, moving from a more general level to specific applications. The three research threads comprise, first, theoretical discussions and speculations with regard to both

  11. Evolutionary design assistants for architecture

    Directory of Open Access Journals (Sweden)

    N. Onur Sönmez

    2015-04-01

    Full Text Available In its parallel pursuit of an increased competitivity for design offices and more pleasurable and easier workflows for designers, artificial design intelligence is a technical, intellectual, and political challenge. While human-machine cooperation has become commonplace through Computer Aided Design (CAD tools, a more improved collaboration and better support appear possible only through an endeavor into a kind of artificial design intelligence, which is more sensitive to the human perception of affairs.Considered as part of the broader Computational Design studies, the research program of this quest can be called Artificial / Autonomous / Automated Design (AD. The current available level of Artificial Intelligence (AI for design is limited and a viable aim for current AD would be to develop design assistants that are capable of producing drafts for various design tasks. Thus, the overall aim of this thesis is the development of approaches, techniques, and tools towards artificial design assistants that offer a capability for generating drafts for sub-tasks within design processes. The main technology explored for this aim is Evolutionary Computation (EC, and the target design domain is architecture. The two connected research questions of the study concern, first, the investigation of the ways to develop an architectural design assistant, and secondly, the utilization of EC for the development of such assistants.While developing approaches, techniques, and computational tools for such an assistant, the study also carries out a broad theoretical investigation into the main problems, challenges, and requirements towards such assistants on a rather overall level. Therefore, the research is shaped as a parallel investigation of three main threads interwoven along several levels, moving from a more general level to specific applications. The three research threads comprise, first, theoretical discussions and speculations with regard to both existing

  12. Evolutionary theory in letters to the editor.

    Science.gov (United States)

    Silva, Eric Orion; Lowe, Clayton Cory

    2015-05-01

    This research note presents the results of a content analysis of 234 letters to the editors that discuss evolutionary theory and were published in American newspapers. We find that letters to the editor both support and hinder the cause of teaching evolutionary theory in American secondary schools. On the one hand, anti-evolutionary theory messages are marginalized in the letters section. This marginalization signals a low level of legitimacy for creationism. It might also contribute to the sense of tension that sustains creationist identities. On the other hand, relatively few letters explicitly note the fact that scientists or the scientific community accept evolution. Interestingly, the obscuration of the scientific community's support for evolutionary theory occurs both in letters supporting and opposing evolutionary theory. © The Author(s) 2014.

  13. A Hybrid Chaotic Quantum Evolutionary Algorithm

    DEFF Research Database (Denmark)

    Cai, Y.; Zhang, M.; Cai, H.

    2010-01-01

    A hybrid chaotic quantum evolutionary algorithm is proposed to reduce amount of computation, speed up convergence and restrain premature phenomena of quantum evolutionary algorithm. The proposed algorithm adopts the chaotic initialization method to generate initial population which will form...... and enhance the global search ability. A large number of tests show that the proposed algorithm has higher convergence speed and better optimizing ability than quantum evolutionary algorithm, real-coded quantum evolutionary algorithm and hybrid quantum genetic algorithm. Tests also show that when chaos...... is introduced to quantum evolutionary algorithm, the hybrid chaotic search strategy is superior to the carrier chaotic strategy, and has better comprehensive performance than the chaotic mutation strategy in most of cases. Especially, the proposed algorithm is the only one that has 100% convergence rate in all...

  14. Vivienda temporal para refugiados

    OpenAIRE

    Amonarraiz Gutiérrez, Ana

    2015-01-01

    El proyecto se centra en el diseño y desarrollo de un espacio destinado a vivienda temporal para dar hogar a personas que han perdido su casa. Este tipo de vivienda es fundamental dentro del proceso de recuperación post-desastre ya que la construcción inmediata de viviendas permanentes es utópica. El objetivo principal es la construcción de una vivienda temporal formada por elementos prefabricados, logrando así una mayor rapidez en su montaje. Esto también permitirá que cualquier component...

  15. Leveraging Distant Relatedness to Quantify Human Mutation and Gene-Conversion Rates

    NARCIS (Netherlands)

    Palamara, Pier Francesco; Francioli, Laurent C; Wilton, Peter R; Genovese, Giulio; Gusev, Alexander; Finucane, Hilary K; Sankararaman, Sriram; Sunyaev, Shamil R; de Bakker, Paul I W; Wakeley, John; Pe'er, Itsik; Price, Alkes L

    2015-01-01

    The rate at which human genomes mutate is a central biological parameter that has many implications for our ability to understand demographic and evolutionary phenomena. We present a method for inferring mutation and gene-conversion rates by using the number of sequence differences observed in

  16. Inflated impact factors? The true impact of evolutionary papers in non-evolutionary journals.

    Directory of Open Access Journals (Sweden)

    Erik Postma

    Full Text Available Amongst the numerous problems associated with the use of impact factors as a measure of quality are the systematic differences in impact factors that exist among scientific fields. While in theory this can be circumvented by limiting comparisons to journals within the same field, for a diverse and multidisciplinary field like evolutionary biology, in which the majority of papers are published in journals that publish both evolutionary and non-evolutionary papers, this is impossible. However, a journal's overall impact factor may well be a poor predictor for the impact of its evolutionary papers. The extremely high impact factors of some multidisciplinary journals, for example, are by many believed to be driven mostly by publications from other fields. Despite plenty of speculation, however, we know as yet very little about the true impact of evolutionary papers in journals not specifically classified as evolutionary. Here I present, for a wide range of journals, an analysis of the number of evolutionary papers they publish and their average impact. I show that there are large differences in impact among evolutionary and non-evolutionary papers within journals; while the impact of evolutionary papers published in multidisciplinary journals is substantially overestimated by their overall impact factor, the impact of evolutionary papers in many of the more specialized, non-evolutionary journals is significantly underestimated. This suggests that, for evolutionary biologists, publishing in high-impact multidisciplinary journals should not receive as much weight as it does now, while evolutionary papers in more narrowly defined journals are currently undervalued. Importantly, however, their ranking remains largely unaffected. While journal impact factors may thus indeed provide a meaningful qualitative measure of impact, a fair quantitative comparison requires a more sophisticated journal classification system, together with multiple field

  17. Temporal compressive sensing systems

    Energy Technology Data Exchange (ETDEWEB)

    Reed, Bryan W.

    2017-12-12

    Methods and systems for temporal compressive sensing are disclosed, where within each of one or more sensor array data acquisition periods, one or more sensor array measurement datasets comprising distinct linear combinations of time slice data are acquired, and where mathematical reconstruction allows for calculation of accurate representations of the individual time slice datasets.

  18. Temporal Concurrent Constraint Programming

    DEFF Research Database (Denmark)

    Nielsen, Mogens; Palamidessi, Catuscia; Valencia, Frank Dan

    2002-01-01

    The ntcc calculus is a model of non-deterministic temporal concurrent constraint programming. In this paper we study behavioral notions for this calculus. In the underlying computational model, concurrent constraint processes are executed in discrete time intervals. The behavioral notions studied...

  19. Temporal Concurrent Constraint Programming

    DEFF Research Database (Denmark)

    Valencia, Frank Dan

    Concurrent constraint programming (ccp) is a formalism for concurrency in which agents interact with one another by telling (adding) and asking (reading) information in a shared medium. Temporal ccp extends ccp by allowing agents to be constrained by time conditions. This dissertation studies...

  20. Mesial temporal sclerosis

    African Journals Online (AJOL)

    Kurt

    2005-07-29

    Jul 29, 2005 ... Introduction. Mesial temporal sclerosis is the commonest cause of partial complex seizures. The aetiology of this condi- tion is controversial, but it is postulat- ed that both acquired and develop- mental processes may be involved. Familial cases have also been reported. Magnetic resonance imaging. (MRI) ...

  1. Temporal bone imaging

    Energy Technology Data Exchange (ETDEWEB)

    Lemmerling, Marc [Algemeen Ziekenhuis Sint-Lucas, Gent (Belgium). Dept. of Radiology; Foer, Bert de (ed.) [Sint-Augustinus Ziekenhuis, Wilrijk (Belgium). Dept. of Radiology

    2015-04-01

    Complete overview of imaging of normal and diseased temporal bone. Straightforward structure to facilitate learning. Detailed consideration of newer imaging techniques, including the hot topic of diffusion-weighted imaging. Includes a chapter on anatomy that will be of great help to the novice interpreter of imaging findings. Excellent illustrations throughout. This book provides a complete overview of imaging of normal and diseased temporal bone. After description of indications for imaging and the cross-sectional imaging anatomy of the area, subsequent chapters address the various diseases and conditions that affect the temporal bone and are likely to be encountered regularly in clinical practice. The classic imaging methods are described and discussed in detail, and individual chapters are included on newer techniques such as functional imaging and diffusion-weighted imaging. There is also a strong focus on postoperative imaging. Throughout, imaging findings are documented with the aid of numerous informative, high-quality illustrations. Temporal Bone Imaging, with its straightforward structure based essentially on topography, will prove of immense value in daily practice.

  2. Communication, Technology, Temporality

    Directory of Open Access Journals (Sweden)

    Mark A. Martinez

    2012-08-01

    Full Text Available This paper proposes a media studies that foregrounds technological objects as communicative and historical agents. Specifically, I take the digital computer as a powerful catalyst of crises in communication theories and certain key features of modernity. Finally, the computer is the motor of “New Media” which is at once a set of technologies, a historical epoch, and a field of knowledge. As such the computer shapes “the new” and “the future” as History pushes its origins further in the past and its convergent quality pushes its future as a predominate medium. As treatment of information and interface suggest, communication theories observe computers, and technologies generally, for the mediated languages they either afford or foreclose to us. My project describes the figures information and interface for the different ways they can be thought of as aspects of communication. I treat information not as semantic meaning, formal or discursive language, but rather as a physical organism. Similarly an interface is not a relationship between a screen and a human visual intelligence, but is instead a reciprocal, affective and physical process of contact. I illustrate that historically there have been conceptions of information and interface complimentary to mine, fleeting as they have been in the face of a dominant temporality of mediation. I begin with a theoretically informed approach to media history, and extend it to a new theory of communication. In doing so I discuss a model of time common to popular, scientific, and critical conceptions of media technologies especially in theories of computer technology. This is a predominate model with particular rules of temporal change and causality for thinking about mediation, and limits the conditions of possibility for knowledge production about communication. I suggest a new model of time as integral to any event of observation and analysis, and that human mediation does not exhaust the

  3. Literature mining of protein-residue associations with graph rules learned through distant supervision

    Directory of Open Access Journals (Sweden)

    Ravikumar KE

    2012-10-01

    Full Text Available Abstract Background We propose a method for automatic extraction of protein-specific residue mentions from the biomedical literature. The method searches text for mentions of amino acids at specific sequence positions and attempts to correctly associate each mention with a protein also named in the text. The methods presented in this work will enable improved protein functional site extraction from articles, ultimately supporting protein function prediction. Our method made use of linguistic patterns for identifying the amino acid residue mentions in text. Further, we applied an automated graph-based method to learn syntactic patterns corresponding to protein-residue pairs mentioned in the text. We finally present an approach to automated construction of relevant training and test data using the distant supervision model. Results The performance of the method was assessed by extracting protein-residue relations from a new automatically generated test set of sentences containing high confidence examples found using distant supervision. It achieved a F-measure of 0.84 on automatically created silver corpus and 0.79 on a manually annotated gold data set for this task, outperforming previous methods. Conclusions The primary contributions of this work are to (1 demonstrate the effectiveness of distant supervision for automatic creation of training data for protein-residue relation extraction, substantially reducing the effort and time involved in manual annotation of a data set and (2 show that the graph-based relation extraction approach we used generalizes well to the problem of protein-residue association extraction. This work paves the way towards effective extraction of protein functional residues from the literature.

  4. Influence of road network and population demand assumptions in evacuation modeling for distant tsunamis

    Science.gov (United States)

    Henry, Kevin; Wood, Nathan J.; Frazier, Tim G.

    2017-01-01

    Tsunami evacuation planning in coastal communities is typically focused on local events where at-risk individuals must move on foot in a matter of minutes to safety. Less attention has been placed on distant tsunamis, where evacuations unfold over several hours, are often dominated by vehicle use and are managed by public safety officials. Traditional traffic simulation models focus on estimating clearance times but often overlook the influence of varying population demand, alternative modes, background traffic, shadow evacuation, and traffic management alternatives. These factors are especially important for island communities with limited egress options to safety. We use the coastal community of Balboa Island, California (USA), as a case study to explore the range of potential clearance times prior to wave arrival for a distant tsunami scenario. We use a first-in–first-out queuing simulation environment to estimate variations in clearance times, given varying assumptions of the evacuating population (demand) and the road network over which they evacuate (supply). Results suggest clearance times are less than wave arrival times for a distant tsunami, except when we assume maximum vehicle usage for residents, employees, and tourists for a weekend scenario. A two-lane bridge to the mainland was the primary traffic bottleneck, thereby minimizing the effect of departure times, shadow evacuations, background traffic, boat-based evacuations, and traffic light timing on overall community clearance time. Reducing vehicular demand generally reduced clearance time, whereas improvements to road capacity had mixed results. Finally, failure to recognize non-residential employee and tourist populations in the vehicle demand substantially underestimated clearance time.

  5. Local and distant source contributions to secondary organic aerosol in the Beijing urban area in summer

    Science.gov (United States)

    Lin, Jian; An, Junling; Qu, Yu; Chen, Yong; Li, Ying; Tang, Yujia; Wang, Feng; Xiang, Weiling

    2016-01-01

    Quantification of local and distant source contributions to particulate matter is a key issue to improving air quality in large urban areas, but few studies have focused on secondary organic aerosol (SOA) source contributions in a large area, especially in China. In this study, we extended the Comprehensive Air Quality Model with Extensions (CAMX) version 5.4, replacing the two-product approach by the volatility basis-set (VBS) approach, with updated SOA yields based on smog chamber studies. The modules related to the computationally efficient particulate source apportionment technology (PSAT) used in CAMX v5.4 were extended based on the volatility basis set (VBS) approach. The updated version of the CAMX model was then used to calculate the local and distant source contributions to SOA in Beijing for the first time. The results indicated that the VBS approach substantially improved hourly, daily, and monthly SOA simulations, compared with the two-product approach and the observations. In August 2007, the local source contributions to anthropogenic and biogenic SOA in Beijing were 23.8% and 16.6%, respectively; distant sources dominated for both anthropogenic and biogenic SOA in Beijing: Northern Hebei, Middle Hebei, Northeast China, Inner Mongolia, Shandong, and Tianjin (including Xianghe) contributed 5.1%-18.2% to anthropogenic SOA in Beijing; whereas, Inner Mongolia, Northern Hebei, and Northeast China contributed 12.2%, 18.6%, and 10.1%, respectively, to biogenic SOA in Beijing. Additionally, other areas outside China respectively contributed 5.3% and 10.8% to anthropogenic and biogenic SOA in Beijing: this could be related to strong summer monsoon.

  6. Beclin 1 Expression is Closely Linked to Colorectal Carcinogenesis and Distant Metastasis of Colorectal Carcinoma

    Directory of Open Access Journals (Sweden)

    Mei-Ying Zhang

    2014-08-01

    Full Text Available Beclin 1 participates in development, autophagy, differentiation, anti- apoptosis, neurodegeneration, tumorigenesis and cancer progression. The roles of Beclin 1 in colorectal carcinogenesis and its subsequent progression are still unclear. Here, the mRNA and protein expression of Beclin 1 were determined in colorectal carcinoma and matched mucosa by Reverse transcriptase-polymerase chain reaction and Western blot. Immunohistochemistry and in situ hybridization (ISH were performed on tissue microarryer with colorectal carcinoma, adenoma and mucosa. The expression of Beclin 1 mRNA and protein was found to be higher in colorectal carcinoma than matched mucosa by real-time PCR and Western blot (p < 0.05. According to the ISH data, Beclin 1 expression was lower in colorectal non-neoplastic mucosa (NNM than adenoma and carcinoma (p < 0.05. Immunohistochemically, primary carcinoma showed stronger Beclin 1 expression than NNM and metastatic carcinoma in the liver (p < 0.05. Beclin 1 protein expression was negatively related to liver and distant metastasis (p < 0.05, but not correlated with age, sex, depth of invasion, lymphatic or venous invasion, lymph node metastasis, tumor-node-metastasis (TNM staging, differentiation or serum carcinoembryonic antigen (CEA concentration (p > 0.05. Survival analysis indicated that Beclin 1 expression was not linked to favorable prognosis of the patients with colorectal carcinoma (p > 0.05. Cox’s model indicated that depth of invasion and distant metastasis were independent prognostic factors for colorectal carcinomas (p < 0.05. It was suggested that Beclin 1 expression is closely linked to colorectal carcinogenesis and distant metastasis of colorectal carcinoma.

  7. Molecular predictors of locoregional and distant metastases in oropharyngeal squamous cell carcinoma.

    Science.gov (United States)

    Barber, Brittany R; Biron, Vincent L; Klimowicz, Alexander C; Puttagunta, Lakshmi; Côté, David W J; Seikaly, Hadi

    2013-10-16

    The incidence of oropharyngeal squamous cell carcinoma (OPSCC) is increasing due to fundamental changes in oncogenesis related to effects of the human papilomavirus (HPV). Virally-mediated tumours behave and respond to treatment differently than their classic, carcinogenically-mediated counterparts despite similar stage and grade of disease. This difference in behaviour has lead to investigation of etiologies of OPSCC at the molecular level. This study was designed to identify biomarker profiles predictive of locoregional and distant metastases and recurrence in OPSCC. Cross-sectional study of a prospectively-collected oropharyngeal tumour database was undertaken. All patients with OPSCC presenting to the University of Alberta Hospital from 2002-2009 were included in the study. Data collection from the Alberta Cancer Registry, including demographics, nodal status, distant metastases, treatment, recurrence, and survival, was undertaken. Tissue micro-arrays (TMAs) were constructed for each tumour specimen using triplicate cores (0.6mm) of formalin-fixed, paraffin-embedded (FFPE) pre-treatment tumour tissue. TMAs were processed using immunohistochemistry for p16, EGFR, Ki67, p53, and Bcl-XL. Positivity for each biomarker was determined using quantified AQUAnalysis ® scores on histoplots. Multivariate statistics were utilized to assess the relationship between each biomarker and locoregional and distant metastases, as well as recurrence-free survival (RFS). High expression of p16 (p=0.000) and Bcl-XL (p=0.039) independently demonstrated a significant association with nodal disease at presentation. Kaplan-Meier analysis demonstrated improved RFS in patients with high p16 and decreased RFS in patients with high p53 expression. Cox regression analysis supported p16 as an independent prognosticator for improved RFS. p53 demonstrated an association with recurrence, but when compared to p16 status, nodal status, and staging, was not an independent predictor of recurrence

  8. Distant metastases following permanent interstitial brachytherapy for patients with clinically localized prostate cancer.

    Science.gov (United States)

    Taira, Al V; Merrick, Gregory S; Galbreath, Robert W; Butler, Wayne M; Lief, Jonathan; Adamovich, Edward; Wallner, Kent E

    2012-02-01

    Recent publications have suggested high-risk patients undergoing radical prostatectomy have a lower risk of distant metastases and improved cause-specific survival (CSS) than patients receiving definitive external beam radiation therapy (XRT). To date, none of these studies has compared distant metastases and CSS in brachytherapy patients. In this study, we evaluate such parameters in a consecutive cohort of brachytherapy patients. From April 1995 to June 2007, 1,840 consecutive patients with clinically localized prostate cancer were treated with brachytherapy. Risk groups were stratified according to National Comprehensive Cancer Network (www.nccn.org) guidelines. Subgroups of 658, 893, and 289 patients were assigned to low, intermediate, and high-risk categories. Median follow-up was 7.2 years. Along with brachytherapy implantation, 901 (49.0%) patients received supplemental XRT, and 670 (36.4%) patients received androgen deprivation therapy (median duration, 4 months). The mode of failure (biochemical, local, or distant) was determined for each patient for whom therapy failed. Cause of death was determined for each deceased patient. Multiple parameters were evaluated for impact on outcome. For the entire cohort, metastases-free survival (MFS) and CSS at 12 years were 98.1% and 98.2%, respectively. When rates were stratified by low, intermediate, and high-risk groups, the 12-year MFS was 99.8%, 98.1%, and 93.8% (p treatment, whereas CSS was most closely associated with Gleason score. Excellent CSS and MFS rates are achievable with high-quality brachytherapy for low, intermediate, and high-risk patients. These results compare favorably to alternative treatment modalities. In particular, our MFS and CSS rates for high-risk patients appear superior to those of published radical prostatectomy series. Copyright © 2012 Elsevier Inc. All rights reserved.

  9. Progressive APOBEC3B mRNA expression in distant breast cancer metastases.

    Directory of Open Access Journals (Sweden)

    Anieta M Sieuwerts

    Full Text Available APOBEC3B was recently identified as a gain-of-function enzymatic source of mutagenesis, which may offer novel therapeutic options with molecules that specifically target this enzyme. In primary breast cancer, APOBEC3B mRNA is deregulated in a substantial proportion of cases and its expression is associated with poor prognosis. However, its expression in breast cancer metastases, which are the main causes of breast cancer-related death, remained to be elucidated.RNA was isolated from 55 primary breast cancers and paired metastases, including regional lymph node (N = 20 and distant metastases (N = 35. APOBEC3B mRNA levels were measured by RT-qPCR. Expression levels of the primary tumors and corresponding metastases were compared, including subgroup analysis by estrogen receptor (ER/ESR1 status.Overall, APOBEC3B mRNA levels of distant metastases were significantly higher as compared to the corresponding primary breast tumor (P = 0.0015, an effect that was not seen for loco-regional lymph node metastases (P = 0.23. Subgroup analysis by ER-status showed that increased APOBEC3B levels in distant metastases were restricted to metastases arising from ER-positive primary breast cancers (P = 0.002. However, regarding ER-negative primary tumors, only loco-regional lymph node metastases showed increased APOBEC3B expression when compared to the corresponding primary tumor (P = 0.028.APOBEC3B mRNA levels are significantly higher in breast cancer metastases as compared to the corresponding ER-positive primary tumors. This suggests a potential role for APOBEC3B in luminal breast cancer progression, and consequently, a promising role for anti-APOBEC3B therapies in advanced stages of this frequent form of breast cancer.

  10. Social representations of climate change in Swedish lay focus groups: local or distant, gradual or catastrophic?

    Science.gov (United States)

    Wibeck, Victoria

    2014-02-01

    This paper explores social representations of climate change, investigating how climate change is discussed by Swedish laypeople interacting in focus group interviews. The analysis focuses on prototypical examples and metaphors, which were key devices for objectifying climate change representations. The paper analyzes how the interaction of focus group participants with other speakers, ideas, arguments, and broader social representations shaped their representations of climate change. Climate change was understood as a global but distant issue with severe consequences. There was a dynamic tension between representations of climate change as a gradual vs. unpredictable process. Implications for climate change communication are discussed.

  11. Metaphor, popular science, and semantic tagging: Distant reading with the Historical Thesaurus of English

    OpenAIRE

    Alexander, Marc; Dallachy, Fraser; Piao, Scott; Baron, Alistair; Rayson, Paul

    2015-01-01

    The use of metaphor in popular science is widespread to aid readers’ conceptions of the scientific concepts under discussion. Almost all research in this area has been done by careful close reading of the text(s) in question, but this article describes—for the first time—a digital ‘distant reading’ analysis of popular science, using a system created by a team from Glasgow and Lancaster. This team, as part of the SAMUELS project, has developed semantic tagging software which is based upon the ...

  12. Four new species of the genus Mongoliana Distant (Hemiptera: Fulgoromorpha: Issidae) from southern China.

    Science.gov (United States)

    Meng, Rui; Wang, Yinglun; Qin, Daozheng

    2016-01-05

    Four new species in the planthopper genus Mongoliana Distant from southern China (Hemiptera: Fulgoromorpha: Issidae) are reported. Three of them, M. bistriata sp. nov., M. latistriata sp. nov. and M. albimaculata sp. nov., are described and illustrated; the fourth new one, M. arcuata sp. nov., is briefly described for M. triangularis Chen, Zhang & Chang which was a misidentification of M. triangularis Che, Wang & Chou. M. recurrens (Butler, 1875) is re-described and remarks for its current status is given. A key to all known species of Mongoliana is provided. The distribution and morphological peculiarities of the genus are briefly discussed.

  13. Photo-acoustic and video-acoustic methods for sensing distant sound sources

    Science.gov (United States)

    Slater, Dan; Kozacik, Stephen; Kelmelis, Eric

    2017-05-01

    Long range telescopic video imagery of distant terrestrial scenes, aircraft, rockets and other aerospace vehicles can be a powerful observational tool. But what about the associated acoustic activity? A new technology, Remote Acoustic Sensing (RAS), may provide a method to remotely listen to the acoustic activity near these distant objects. Local acoustic activity sometimes weakly modulates the ambient illumination in a way that can be remotely sensed. RAS is a new type of microphone that separates an acoustic transducer into two spatially separated components: 1) a naturally formed in situ acousto-optic modulator (AOM) located within the distant scene and 2) a remote sensing readout device that recovers the distant audio. These two elements are passively coupled over long distances at the speed of light by naturally occurring ambient light energy or other electromagnetic fields. Stereophonic, multichannel and acoustic beam forming are all possible using RAS techniques and when combined with high-definition video imagery it can help to provide a more cinema like immersive viewing experience. A practical implementation of a remote acousto-optic readout device can be a challenging engineering problem. The acoustic influence on the optical signal is generally weak and often with a strong bias term. The optical signal is further degraded by atmospheric seeing turbulence. In this paper, we consider two fundamentally different optical readout approaches: 1) a low pixel count photodiode based RAS photoreceiver and 2) audio extraction directly from a video stream. Most of our RAS experiments to date have used the first method for reasons of performance and simplicity. But there are potential advantages to extracting audio directly from a video stream. These advantages include the straight forward ability to work with multiple AOMs (useful for acoustic beam forming), simpler optical configurations, and a potential ability to use certain preexisting video recordings. However

  14. Empathy: from mind reading to the reading of a distant text.

    Science.gov (United States)

    Neuman, Yair

    2010-09-01

    In the psychoanalytic literature empathy is commonly discussed as a form of "mind reading", which is deeply associated with the capacity to mirror the other's mental state. In this paper, I propose an alternative perspective on empathy as the process of reading a distant text. This perspective is illustrated through a Talmudic story and by weaving a thread between Bakhtin, Bion and Lacan. The paper concludes by pointing to the danger of empathy as a hidden form of projective identification that provides the reader with a false sense of control rather than with negative capability for otherness.

  15. Feminism and Society: Solidarity Amongst Pakistani Women Still a Distant Dream

    Directory of Open Access Journals (Sweden)

    Dr. Farhat Jabeen

    2013-06-01

    Patriarchal structure of society, socio-customary practices and discrimination against women are very serious concerns/issues which need to be understood as multidimensional problem. This paper examines the role of feminism on gender development in south Asian perspective especially in Pakistan. Pakistani women seem to have been circumscribed in bounds of religious, cultural and national ideologies as envisioned by the patriarchy of Pakistan. Due to certain cultural, male domination state of affairs the solidarity amongst Pakistani women still distant dream. Current research paper would draw attention to issue mentioned above.

  16. Signals from the gut microbiota to distant organs in physiology and disease

    DEFF Research Database (Denmark)

    Schroeder, Bjoern O; Bäckhed, Gert Fredrik

    2016-01-01

    The ecosystem of the human gut consists of trillions of bacteria forming a bioreactor that is fueled by dietary macronutrients to produce bioactive compounds. These microbiota-derived metabolites signal to distant organs in the body, which enables the gut bacteria to connect to the immune...... obesity and inflammatory diseases to behavioral and physiological abnormalities associated with neurodevelopmental disorders. In this Review, we will discuss microbiota-host cross-talk and intestinal microbiome signaling to extraintestinal organs. We will review mechanisms of how this communication might...... contribute to host physiology and discuss how misconfigured signaling might contribute to different diseases....

  17. Piroeletricidade e emissão de infravermelho distante da turmalina

    OpenAIRE

    Fernando Soares Lameiras; Valéria Alves Rodrigues de Melo; José Maria Leal

    2005-01-01

    Um modelo tridimensional de computador de esferas rígidas da estrutura cristalina da turmalina revela que oscilações anarmônicas são impostas ao sítio W, o que, teoricamente, pode explicar a sua piroeletricidade e a emissão de infravermelho distante. Entretanto esses efeitos devem ser pequenos. Medidas das suas grandezas são necessárias para explicação do uso industrial do pó de turmalina.A three dimensional rigid ball computer model of the tourmaline crystal structure shows that anharmonic o...

  18. Upregulation of Claudin-4, CAIX and GLUT-1 in distant breast cancer metastases.

    Science.gov (United States)

    Jiwa, Laura S; van Diest, Paul J; Hoefnagel, Laurien D; Wesseling, Jelle; Wesseling, Pieter; Moelans, Cathy B

    2014-11-22

    Several studies have shown that the immunophenotype of distant breast cancer metastases may differ significantly from that of the primary tumor, especially with regard to differences in the level of hormone receptor protein expression, a process known as receptor conversion. This study aimed to compare expression levels of several membrane proteins between primary breast tumors and their corresponding distant metastases in view of their potential applicability for molecular imaging and drug targeting. Expression of Claudin-4, EGFR, CAIX, GLUT-1 and IGF1R was assessed by immunohistochemistry on tissue microarrays composed of 97 paired primary breast tumors and their distant (non-bone) metastases. In both the primary cancers and the metastases, Claudin-4 was most frequently expressed, followed by GLUT-1, CAIX and EGFR.From primary breast cancers to their distant metastases there was positive to negative conversion, e.g. protein expression in the primary tumor with no expression in its paired metastasis, in 6%, 19%, 12%, 38%, and 0% for Claudin-4 (n.s), GLUT-1 (n.s), CAIX (n.s), EGFR (n.s) and IGF1R (n.s) respectively. Negative to positive conversion was seen in 65%, 47%, 43%, 9% and 0% of cases for Claudin-4 (p = 0.049), GLUT-1 (p = 0.024), CAIX (p = 0.002), EGFR (n.s.) and IGF1R (n.s.) respectively. Negative to positive conversion of Claudin-4 in the metastasis was significantly associated with tumor size (p = 0.015), negative to positive conversion of EGFR with negative PR status (p = 0.046) and high MAI (p = 0.047) and GLUT-1 negative to positive conversion with (neo)adjuvant chemotherapy (p = 0.039) and time to metastasis formation (p = 0.034). CAIX and GLUT-1 expression in the primary tumor were significantly associated with high MAI (p = 0.008 and p = 0.038 respectively). Claudin-4 is frequently expressed in primary breast cancers but especially in their metastases and is thereby an attractive membrane bound molecular imaging and drug target. Conversion in

  19. Historically aggressive types of follicular cell-derived thyroid cancer often have radioactive avid distant metastases: a study of 314 patients with distant metastases at a single institution

    Energy Technology Data Exchange (ETDEWEB)

    Tala, H.P.; Rondeau, G.; Fagin, J.A.; Tuttle, R.M. [Endocrinology Division, Department of Medicine, Nuclear Medicine Division, Memorial Sloan Kettering Cancer Center, New-York (United States); Ghossein, R.A. [Pathology Department, Nuclear Medecine Division, Memorial Sloan Kettering Cancer Center, New-York (United States); Grewal, R.K.; Larson, S.M. [Radiology Department, Nuclear Medicine Division, Memorial Sloan Kettering Cancer Center, New-York (United States)

    2012-07-01

    Radioactive iodine (RAI) remains one of the primary treatment options for metastatic, follicular cell derived thyroid cancers. The aim of this study was to determine the likelihood that metastatic lesions arising from one of the aggressive thyroid cancer histologies [tall cell variant of papillary thyroid carcinoma (TCV-PTC), poorly differentiated thyroid carcinoma (PDTC) and Hurthle cell carcinoma (HCC)] would demonstrate sufficient RAI avidity for visualization on RAI scanning and therefore could potentially benefit from RAI therapy. The study shows that in patients selected for RAI scanning or therapy at our center, RAI avid lesions can be identified in more than two thirds of the patients with distant metastases arising in the setting of C-PTC, WD-FTC, FV-PTC, TCV-PTC, or PDTC primary tumors. While RAI avidity on a post-therapy scan does not always correlate with clinically significant tumor killing activity, it is likely that some of these patients with RAI avid metastatic disease did obtain a clinical benefit

  20. Effects of temperature and food on the development of Dysdercus maurus Distant (Hemiptera, Pyrrhocoridae); Efeitos da temperatura e do alimento no desenvolvimento de Dysdercus maurus Distant (Hemiptera, Pyrrhocoridae)

    Energy Technology Data Exchange (ETDEWEB)

    Almeida, Fabio Souto [Universidade Federal Rural do Rio de Janeiro (UFRRJ), Seropedica, RJ (Brazil). Dept. de Ciencias Ambientais], e-mail: fbio_almeida@yahoo.com.br; Goncalves, Lenicio [Universidade Federal Rural do Rio de Janeiro (UFRRJ), Seropedica, RJ (Brazil). Dept. de Biologia Animal. Area de Biologia], e-mail: lencygon@globo.com

    2007-10-15

    Dysdercus maurus Distant, 1901 (Hemiptera, Pyrrhocoridae) is an important pest on Gossypium spp. (cotton tree), Citrus sinensis Osbeck (Rutaceae) and Citrus reticulata Blanco (Rutaceae) crops. This insect also feeds on seeds of Chorisia speciosa St. Hil. (Bombacaceae). This work aimed to evaluate the effects of temperature and food on the development of D. maurus. Eight treatments were carried out, in six of them bugs were fed with seeds of C. speciosa and kept at 15, 18, 20, 25 and 30 {+-} 1 deg C, 80 {+-} 3% RH and 12h photo phase or in laboratory conditions (23.5 {+-} 2.6 deg C, 73.3 {+-} 9.9 % RH), and in the other two treatments bugs were fed with seeds of cotton variety IAC-22 and kept at 25 or 30 deg C. In all treatments five immature stages were observed. The increase of temperature caused reduction in the developmental time. The temperature of 15 deg C disabled nymphal eclosion and was also lethal to those nymphs ecloded at other temperatures. The lower mortality of nymphs occurred in the temperature of 25 deg C with cotton as food (24.07%). The lower threshold temperature (Tb) occurred for the first instar (11.54 deg C) and the higher for the second instar (15.33 deg C). The females of D. maurus required more degree-days (329.93 degree-days) than males (300.49 degree-days) until adult emergence. (author)

  1. High-order epistasis shapes evolutionary trajectories.

    Science.gov (United States)

    Sailer, Zachary R; Harms, Michael J

    2017-05-01

    High-order epistasis-where the effect of a mutation is determined by interactions with two or more other mutations-makes small, but detectable, contributions to genotype-fitness maps. While epistasis between pairs of mutations is known to be an important determinant of evolutionary trajectories, the evolutionary consequences of high-order epistasis remain poorly understood. To determine the effect of high-order epistasis on evolutionary trajectories, we computationally removed high-order epistasis from experimental genotype-fitness maps containing all binary combinations of five mutations. We then compared trajectories through maps both with and without high-order epistasis. We found that high-order epistasis strongly shapes the accessibility and probability of evolutionary trajectories. A closer analysis revealed that the magnitude of epistasis, not its order, predicts is effects on evolutionary trajectories. We further find that high-order epistasis makes it impossible to predict evolutionary trajectories from the individual and paired effects of mutations. We therefore conclude that high-order epistasis profoundly shapes evolutionary trajectories through genotype-fitness maps.

  2. Evolutionary psychology. Controversies, questions, prospects, and limitations.

    Science.gov (United States)

    Confer, Jaime C; Easton, Judith A; Fleischman, Diana S; Goetz, Cari D; Lewis, David M G; Perilloux, Carin; Buss, David M

    2010-01-01

    Evolutionary psychology has emerged over the past 15 years as a major theoretical perspective, generating an increasing volume of empirical studies and assuming a larger presence within psychological science. At the same time, it has generated critiques and remains controversial among some psychologists. Some of the controversy stems from hypotheses that go against traditional psychological theories; some from empirical findings that may have disturbing implications; some from misunderstandings about the logic of evolutionary psychology; and some from reasonable scientific concerns about its underlying framework. This article identifies some of the most common concerns and attempts to elucidate evolutionary psychology's stance pertaining to them. These include issues of testability and falsifiability; the domain specificity versus domain generality of psychological mechanisms; the role of novel environments as they interact with evolved psychological circuits; the role of genes in the conceptual structure of evolutionary psychology; the roles of learning, socialization, and culture in evolutionary psychology; and the practical value of applied evolutionary psychology. The article concludes with a discussion of the limitations of current evolutionary psychology. 2009 APA, all rights reserved.

  3. Evolutionary history of lorisiform primates.

    Science.gov (United States)

    Rasmussen, D T; Nekaris, K A

    1998-01-01

    be integrated with behavioral and morphological features to develop an adaptive model of lorisoid divergence. By specializing on two different foraging modes early in their radiation, lorisines and galagines subsequently underwent a chain of integrated evolutionary changes eventually having an impact on many components of locomotor behavior, anatomy, physiology, reproduction, life history, and social behavior. Ongoing evolutionary studies of extant galagines are illuminating population phenomena and processes of speciation in an ecological context.

  4. APEX Snaps First Close-up of Star Factories in Distant Universe

    Science.gov (United States)

    2010-03-01

    For the first time, astronomers have made direct measurements of the size and brightness of regions of star-birth in a very distant galaxy, thanks to a chance discovery with the APEX telescope. The galaxy is so distant, and its light has taken so long to reach us, that we see it as it was 10 billion years ago. A cosmic "gravitational lens" is magnifying the galaxy, giving us a close-up view that would otherwise be impossible. This lucky break reveals a hectic and vigorous star-forming life for galaxies in the early Universe, with stellar nurseries forming one hundred times faster than in more recent galaxies. The research is published online today in the journal Nature. Astronomers were observing a massive galaxy cluster [1] with the Atacama Pathfinder Experiment (APEX) telescope, using submillimetre wavelengths of light, when they found a new and uniquely bright galaxy, more distant than the cluster and the brightest very distant galaxy ever seen at submillimetre wavelengths. It is so bright because the cosmic dust grains in the galaxy are glowing after being heated by starlight. The new galaxy has been given the name SMM J2135-0102. "We were stunned to find a surprisingly bright object that wasn't at the expected position. We soon realised it was a previously unknown and more distant galaxy being magnified by the closer galaxy cluster," says Carlos De Breuck from ESO, a member of the team. De Breuck was making the observations at the APEX telescope on the plateau of Chajnantor at an altitude of 5000 m in the Chilean Andes. The new galaxy SMM J2135-0102 is so bright because of the massive galaxy cluster that lies in the foreground. The vast mass of this cluster bends the light of the more distant galaxy, acting as a gravitational lens [2]. As with a telescope, it magnifies and brightens our view of the distant galaxy. Thanks to a fortuitous alignment between the cluster and the distant galaxy, the latter is strongly magnified by a factor of 32. "The magnification

  5. Evolutionary theory and the naturalist fallacy

    DEFF Research Database (Denmark)

    Grodal, Torben Kragh

    2008-01-01

    The article is an invited response to a target article by Joseph Carroll entitled "An evolutionary paradigm for literary study". It argues that the target article  misuse the fact that works of art are based on adaptations that were fitness-enhancing in the era of evolutionary adaptations to claim...... that great work of art are also automatically fitness-enhancing in the present day environment, at that there are simple correllations between whether a work of art has a high aesthetic value and whether it is fitness-enhancing or not.  Keywords :  Evolutionary aesthetics, film theory, literary theory...

  6. Ecological and Temporal Constraints in the Evolution of Bacterial Genomes

    Directory of Open Access Journals (Sweden)

    Jose Luis Martínez

    2011-10-01

    Full Text Available Studies on the experimental evolution of microorganisms, on their in vivo evolution (mainly in the case of bacteria producing chronic infections, as well as the availability of multiple full genomic sequences, are placing bacteria in the playground of evolutionary studies. In the present article we review the differential contribution to the evolution of bacterial genomes that processes such as gene modification, gene acquisition and gene loss may have when bacteria colonize different habitats that present characteristic ecological features. In particular, we review how the different processes contribute to evolution in microbial communities, in free-living bacteria or in bacteria living in isolation. In addition, we discuss the temporal constraints in the evolution of bacterial genomes, considering bacterial evolution from the perspective of processes of short-sighted evolution and punctual acquisition of evolutionary novelties followed by long stasis periods.

  7. Evolutionary optimization of protein folding.

    Directory of Open Access Journals (Sweden)

    Cédric Debès

    Full Text Available Nature has shaped the make up of proteins since their appearance, [Formula: see text]3.8 billion years ago. However, the fundamental drivers of structural change responsible for the extraordinary diversity of proteins have yet to be elucidated. Here we explore if protein evolution affects folding speed. We estimated folding times for the present-day catalog of protein domains directly from their size-modified contact order. These values were mapped onto an evolutionary timeline of domain appearance derived from a phylogenomic analysis of protein domains in 989 fully-sequenced genomes. Our results show a clear overall increase of folding speed during evolution, with known ultra-fast downhill folders appearing rather late in the timeline. Remarkably, folding optimization depends on secondary structure. While alpha-folds showed a tendency to fold faster throughout evolution, beta-folds exhibited a trend of folding time increase during the last [Formula: see text]1.5 billion years that began during the "big bang" of domain combinations. As a consequence, these domain structures are on average slow folders today. Our results suggest that fast and efficient folding of domains shaped the universe of protein structure. This finding supports the hypothesis that optimization of the kinetic and thermodynamic accessibility of the native fold reduces protein aggregation propensities that hamper cellular functions.

  8. Evolutionary genomics of animal personality.

    Science.gov (United States)

    van Oers, Kees; Mueller, Jakob C

    2010-12-27

    Research on animal personality can be approached from both a phenotypic and a genetic perspective. While using a phenotypic approach one can measure present selection on personality traits and their combinations. However, this approach cannot reconstruct the historical trajectory that was taken by evolution. Therefore, it is essential for our understanding of the causes and consequences of personality diversity to link phenotypic variation in personality traits with polymorphisms in genomic regions that code for this trait variation. Identifying genes or genome regions that underlie personality traits will open exciting possibilities to study natural selection at the molecular level, gene-gene and gene-environment interactions, pleiotropic effects and how gene expression shapes personality phenotypes. In this paper, we will discuss how genome information revealed by already established approaches and some more recent techniques such as high-throughput sequencing of genomic regions in a large number of individuals can be used to infer micro-evolutionary processes, historical selection and finally the maintenance of personality trait variation. We will do this by reviewing recent advances in molecular genetics of animal personality, but will also use advanced human personality studies as case studies of how molecular information may be used in animal personality research in the near future.

  9. Evolutionary dynamics under interactive diversity

    Science.gov (United States)

    Su, Qi; Li, Aming; Wang, Long

    2017-10-01

    As evidenced by many cases in human societies, individuals often make different behavior decisions in different interactions, and adaptively adjust their behavior in changeable interactive scenarios. However, up to now, how such diverse interactive behavior affects cooperation dynamics has still remained unknown. Here we develop a general framework of interactive diversity, which models individuals’ separated behavior against distinct opponents and their adaptive adjustment in response to opponents’ strategies, to explore the evolution of cooperation. We find that interactive diversity enables individuals to reciprocate every single opponent, and thus sustains large-scale reciprocal interactions. Our work witnesses an impressive boost of cooperation for a notably extensive range of parameters and for all pairwise games. These results are robust against well-mixed and various networked populations, and against degree-normalized and cumulative payoff patterns. From the perspective of network dynamics, distinguished from individuals competing for nodes in most previous work, in this paper, the system evolves in the form of behavior disseminating along edges. We propose a theoretical method based on evolution of edges, which predicts well both the frequency of cooperation and the compact cooperation clusters. Our thorough investigation clarifies the positive role of interactive diversity in resolving social dilemmas and highlights the significance of understanding evolutionary dynamics from the viewpoint of edge dynamics.

  10. Evolutionary history of the Coccolithoviridae.

    Science.gov (United States)

    Allen, Michael J; Schroeder, Declan C; Holden, Matthew T G; Wilson, William H

    2006-01-01

    We recently determined the genome sequence of the Coccolithoviridae strain Emiliania huxleyi virus 86 (EhV-86), a giant double-stranded DNA (dsDNA) algal virus from the family Phycodnaviridae that infects the marine coccolithophorid E. huxleyi. Here, we determine the phylogenetic relationship between EhV-86 and other large dsDNA viruses. Twenty-five core genes common to nuclear-cytoplasmic large dsDNA virus genomes were identified in the EhV-86 genome; sequence from eight of these genes were used to create a phylogenetic tree in which EhV-86 was placed firmly with the two other members of the Phycodnaviridae. We have also identified a 100-kb region of the EhV-86 genome which appears to have transferred into this genome from an unknown source. Furthermore, the presence of six RNA polymerase subunits (unique among the Phycodnaviridae) suggests both a unique evolutionary history and a unique lifestyle for this intriguing virus.

  11. Evolutionary dynamics of group fairness.

    Science.gov (United States)

    Santos, Fernando P; Santos, Francisco C; Paiva, Ana; Pacheco, Jorge M

    2015-08-07

    The emergence and impact of fairness is commonly studied in the context of 2-person games, notably the Ultimatum Game. Often, however, humans face problems of collective action involving more than two individuals where fairness is known to play a very important role, and whose dynamics cannot be inferred from what is known from 2-person games. Here, we propose a generalization of the Ultimatum Game for an arbitrary number of players--the Multiplayer Ultimatum Game. Proposals are made to a group of responders who must individually reject or accept the proposal. If the total number of individual acceptances stands below a given threshold, the offer will be rejected; otherwise, the offer will be accepted, and equally shared by all responders. We investigate the evolution of fairness in populations of individuals by means of evolutionary game theory, providing both analytical insights and results from numerical simulations. We show how imposing stringent consensuses significantly increases the value of the proposals, leading to fairer outcomes and more tolerant players. Furthermore, we show how stochastic effects--such as imitation errors and/or errors when assessing the fitness of others--may further enhance the overall success in reaching fair collective action. Copyright © 2015 Elsevier Ltd. All rights reserved.

  12. Human adoption in evolutionary perspective.

    Science.gov (United States)

    Silk, J B

    1990-03-01

    Exploitation is a fundamental element of the parental strategies of many species of birds. Cuckoos, for example, lay their eggs in the nest of other birds, who often unwittingly rear the alien nestlings as their own. Nest parasitism is an efficient reproductive strategy for cuckoos, who do not have to worry about building a nest, incubating their eggs, or feeding their nestlings. But not all hosts respond passively to such intrusions. In response to parasitic cowbirds, for example, robins have evolved the ability to detect and selectively eject alien young from their nests. Human parenting strategies differ sharply from the strategies of cuckoos and robins. Unlike cuckoos, we are reluctant to allow our children to be raised by others. Unlike robins, we knowingly rear strange young. What makes human behavior toward children so different from that of cuckoos and robins? Humans seem to share a number of predispositions that facilitate successful adoptive relationships, and the desire to raise children seems to be pervasive among modern humans. Despite these commonalities, patterns of adoption transactions vary greatly among contemporary human societies. This paper considers the origins and causes of cross-cultural variation in human adoptive behavior from an evolutionary perspective.

  13. Evolutionary dynamics of language systems

    Science.gov (United States)

    Wu, Chieh-Hsi; Hua, Xia; Dunn, Michael; Levinson, Stephen C.; Gray, Russell D.

    2017-01-01

    Understanding how and why language subsystems differ in their evolutionary dynamics is a fundamental question for historical and comparative linguistics. One key dynamic is the rate of language change. While it is commonly thought that the rapid rate of change hampers the reconstruction of deep language relationships beyond 6,000–10,000 y, there are suggestions that grammatical structures might retain more signal over time than other subsystems, such as basic vocabulary. In this study, we use a Dirichlet process mixture model to infer the rates of change in lexical and grammatical data from 81 Austronesian languages. We show that, on average, most grammatical features actually change faster than items of basic vocabulary. The grammatical data show less schismogenesis, higher rates of homoplasy, and more bursts of contact-induced change than the basic vocabulary data. However, there is a core of grammatical and lexical features that are highly stable. These findings suggest that different subsystems of language have differing dynamics and that careful, nuanced models of language change will be needed to extract deeper signal from the noise of parallel evolution, areal readaptation, and contact. PMID:29073028

  14. The Evolutionary Origins of Hierarchy.

    Directory of Open Access Journals (Sweden)

    Henok Mengistu

    2016-06-01

    Full Text Available Hierarchical organization-the recursive composition of sub-modules-is ubiquitous in biological networks, including neural, metabolic, ecological, and genetic regulatory networks, and in human-made systems, such as large organizations and the Internet. To date, most research on hierarchy in networks has been limited to quantifying this property. However, an open, important question in evolutionary biology is why hierarchical organization evolves in the first place. It has recently been shown that modularity evolves because of the presence of a cost for network connections. Here we investigate whether such connection costs also tend to cause a hierarchical organization of such modules. In computational simulations, we find that networks without a connection cost do not evolve to be hierarchical, even when the task has a hierarchical structure. However, with a connection cost, networks evolve to be both modular and hierarchical, and these networks exhibit higher overall performance and evolvability (i.e. faster adaptation to new environments. Additional analyses confirm that hierarchy independently improves adaptability after controlling for modularity. Overall, our results suggest that the same force-the cost of connections-promotes the evolution of both hierarchy and modularity, and that these properties are important drivers of network performance and adaptability. In addition to shedding light on the emergence of hierarchy across the many domains in which it appears, these findings will also accelerate future research into evolving more complex, intelligent computational brains in the fields of artificial intelligence and robotics.

  15. Natural pedagogy as evolutionary adaptation.

    Science.gov (United States)

    Csibra, Gergely; Gergely, György

    2011-04-12

    We propose that the cognitive mechanisms that enable the transmission of cultural knowledge by communication between individuals constitute a system of 'natural pedagogy' in humans, and represent an evolutionary adaptation along the hominin lineage. We discuss three kinds of arguments that support this hypothesis. First, natural pedagogy is likely to be human-specific: while social learning and communication are both widespread in non-human animals, we know of no example of social learning by communication in any other species apart from humans. Second, natural pedagogy is universal: despite the huge variability in child-rearing practices, all human cultures rely on communication to transmit to novices a variety of different types of cultural knowledge, including information about artefact kinds, conventional behaviours, arbitrary referential symbols, cognitively opaque skills and know-how embedded in means-end actions. Third, the data available on early hominin technological culture are more compatible with the assumption that natural pedagogy was an independently selected adaptive cognitive system than considering it as a by-product of some other human-specific adaptation, such as language. By providing a qualitatively new type of social learning mechanism, natural pedagogy is not only the product but also one of the sources of the rich cultural heritage of our species.

  16. Evolutionary games in the multiverse.

    Science.gov (United States)

    Gokhale, Chaitanya S; Traulsen, Arne

    2010-03-23

    Evolutionary game dynamics of two players with two strategies has been studied in great detail. These games have been used to model many biologically relevant scenarios, ranging from social dilemmas in mammals to microbial diversity. Some of these games may, in fact, take place between a number of individuals and not just between two. Here we address one-shot games with multiple players. As long as we have only two strategies, many results from two-player games can be generalized to multiple players. For games with multiple players and more than two strategies, we show that statements derived for pairwise interactions no longer hold. For two-player games with any number of strategies there can be at most one isolated internal equilibrium. For any number of players with any number of strategies , there can be at most isolated internal equilibria. Multiplayer games show a great dynamical complexity that cannot be captured based on pairwise interactions. Our results hold for any game and can easily be applied to specific cases, such as public goods games or multiplayer stag hunts.

  17. Evolutionary advantages of adaptive rewarding

    Science.gov (United States)

    Szolnoki, Attila; Perc, Matjaž

    2012-09-01

    Our well-being depends on both our personal success and the success of our society. The realization of this fact makes cooperation an essential trait. Experiments have shown that rewards can elevate our readiness to cooperate, but since giving a reward inevitably entails paying a cost for it, the emergence and stability of such behavior remains elusive. Here we show that allowing for the act of rewarding to self-organize in dependence on the success of cooperation creates several evolutionary advantages that instill new ways through which collaborative efforts are promoted. Ranging from indirect territorial battle to the spontaneous emergence and destruction of coexistence, phase diagrams and the underlying spatial patterns reveal fascinatingly rich social dynamics that explain why this costly behavior has evolved and persevered. Comparisons with adaptive punishment, however, uncover an Achilles heel of adaptive rewarding, coming from over-aggression, which in turn hinders optimal utilization of network reciprocity. This may explain why, despite its success, rewarding is not as firmly embedded into our societal organization as punishment.

  18. Genes from scratch--the evolutionary fate of de novo genes.

    Science.gov (United States)

    Schlötterer, Christian

    2015-04-01

    Although considered an extremely unlikely event, many genes emerge from previously noncoding genomic regions. This review covers the entire life cycle of such de novo genes. Two competing hypotheses about the process of de novo gene birth are discussed as well as the high death rate of de novo genes. Despite the high death rate, some de novo genes are retained and remain functional, even in distantly related species, through their integration into gene networks. Further studies combining gene expression with ribosome profiling in multiple populations across different species will be instrumental for an improved understanding of the evolutionary processes operating on de novo genes. Copyright © 2015 The Author. Published by Elsevier Ltd.. All rights reserved.

  19. The spatial organization of intra-tumour heterogeneity and evolutionary trajectories of metastases in hepatocellular carcinoma

    Science.gov (United States)

    Zhai, Weiwei; Lim, Tony Kiat-Hon; Zhang, Tong; Phang, Su-Ting; Tiang, Zenia; Guan, Peiyong; Ng, Ming-Hwee; Lim, Jia Qi; Yao, Fei; Li, Zheng; Ng, Poh Yong; Yan, Jie; Goh, Brian K.; Chung, Alexander Yaw-Fui; Choo, Su-Pin; Khor, Chiea Chuen; Soon, Wendy Wei-Jia; Sung, Ken Wing-Kin; Foo, Roger Sik-Yin; Chow, Pierce Kah-Hoe

    2017-02-01

    Hepatocellular carcinoma (HCC) has one of the poorest survival rates among cancers. Using multi-regional sampling of nine resected HCC with different aetiologies, here we construct phylogenetic relationships of these sectors, showing diverse levels of genetic sharing, spanning early to late diversification. Unlike the variegated pattern found in colorectal cancers, a large proportion of HCC display a clear isolation-by-distance pattern where spatially closer sectors are genetically more similar. Two resected intra-hepatic metastases showed genetic divergence occurring before and after primary tumour diversification, respectively. Metastatic tumours had much higher variability than their primary tumours, suggesting that intra-hepatic metastasis is accompanied by rapid diversification at the distant location. The presence of co-existing mutations offers the possibility of drug repositioning for HCC treatment. Taken together, these insights into intra-tumour heterogeneity allow for a comprehensive understanding of the evolutionary trajectories of HCC and suggest novel avenues for personalized therapy.

  20. Advanced Image Enhancement Method for Distant Vessels and Structures in Capsule Endoscopy

    Science.gov (United States)

    Pedersen, Marius

    2017-01-01

    This paper proposes an advanced method for contrast enhancement of capsule endoscopic images, with the main objective to obtain sufficient information about the vessels and structures in more distant (or darker) parts of capsule endoscopic images. The proposed method (PM) combines two algorithms for the enhancement of darker and brighter areas of capsule endoscopic images, respectively. The half-unit weighted-bilinear algorithm (HWB) proposed in our previous work is used to enhance darker areas according to the darker map content of its HSV's component V. Enhancement of brighter areas is achieved thanks to the novel threshold weighted-bilinear algorithm (TWB) developed to avoid overexposure and enlargement of specular highlight spots while preserving the hue, in such areas. The TWB performs enhancement operations following a gradual increment of the brightness of the brighter map content of its HSV's component V. In other words, the TWB decreases its averaged weights as the intensity content of the component V increases. Extensive experimental demonstrations were conducted, and, based on evaluation of the reference and PM enhanced images, a gastroenterologist (Ø.H.) concluded that the PM enhanced images were the best ones based on the information about the vessels, contrast in the images, and the view or visibility of the structures in more distant parts of the capsule endoscopy images. PMID:29225668

  1. THE RELATIONSHIP BETWEEN TEACHER IMMEDIACY BEHAVIOURS AND DISTANT LEARNERS’ SOCIAL PRESENCE PERCEPTIONS IN VIDEOCONFERENCING APPLICATIONS

    Directory of Open Access Journals (Sweden)

    Mujgan BOZKAYA

    2008-01-01

    Full Text Available ABSTRACTVideoconferencing systems combine face-to-face and mediated interactions in distance education. We extend the use of a Social Presence measure to on-site (face-to-face learners and distant learners. Comparison between physically present and distant located learners did not indicate significant differences in social presence. Also results indicate that the predicted social presence score for distance instruction is slightly lower than for the on-site instruction for high nonverbal behavior while the reverse is true of low non verbal behaviors. Predicted social presence for face to face instruction is quite higher than for the distance instruction for the high verbal behaviors while the reverse is true of low verbal behaviors. It means that students’ social presence is predicted to be higher in the face to face setting comparing to the videoconferencing course in both models. Additionally, when both nonverbal and verbal behaviors increase, the predicted social presence is facilitated, controlling for the grouping variable. In other words, instructors’ nonverbal and verbal communication skills enhance learners’ social presence in either environment.

  2. Cryptic distant relatives are common in both isolated and cosmopolitan genetic samples.

    Directory of Open Access Journals (Sweden)

    Brenna M Henn

    Full Text Available Although a few hundred single nucleotide polymorphisms (SNPs suffice to infer close familial relationships, high density genome-wide SNP data make possible the inference of more distant relationships such as 2(nd to 9(th cousinships. In order to characterize the relationship between genetic similarity and degree of kinship given a timeframe of 100-300 years, we analyzed the sharing of DNA inferred to be identical by descent (IBD in a subset of individuals from the 23andMe customer database (n = 22,757 and from the Human Genome Diversity Panel (HGDP-CEPH, n = 952. With data from 121 populations, we show that the average amount of DNA shared IBD in most ethnolinguistically-defined populations, for example Native American groups, Finns and Ashkenazi Jews, differs from continentally-defined populations by several orders of magnitude. Via extensive pedigree-based simulations, we determined bounds for predicted degrees of relationship given the amount of genomic IBD sharing in both endogamous and 'unrelated' population samples. Using these bounds as a guide, we detected tens of thousands of 2(nd to 9(th degree cousin pairs within a heterogenous set of 5,000 Europeans. The ubiquity of distant relatives, detected via IBD segments, in both ethnolinguistic populations and in large 'unrelated' populations samples has important implications for genetic genealogy, forensics and genotype/phenotype mapping studies.

  3. Cryptic distant relatives are common in both isolated and cosmopolitan genetic samples.

    Science.gov (United States)

    Henn, Brenna M; Hon, Lawrence; Macpherson, J Michael; Eriksson, Nick; Saxonov, Serge; Pe'er, Itsik; Mountain, Joanna L

    2012-01-01

    Although a few hundred single nucleotide polymorphisms (SNPs) suffice to infer close familial relationships, high density genome-wide SNP data make possible the inference of more distant relationships such as 2(nd) to 9(th) cousinships. In order to characterize the relationship between genetic similarity and degree of kinship given a timeframe of 100-300 years, we analyzed the sharing of DNA inferred to be identical by descent (IBD) in a subset of individuals from the 23andMe customer database (n = 22,757) and from the Human Genome Diversity Panel (HGDP-CEPH, n = 952). With data from 121 populations, we show that the average amount of DNA shared IBD in most ethnolinguistically-defined populations, for example Native American groups, Finns and Ashkenazi Jews, differs from continentally-defined populations by several orders of magnitude. Via extensive pedigree-based simulations, we determined bounds for predicted degrees of relationship given the amount of genomic IBD sharing in both endogamous and 'unrelated' population samples. Using these bounds as a guide, we detected tens of thousands of 2(nd) to 9(th) degree cousin pairs within a heterogenous set of 5,000 Europeans. The ubiquity of distant relatives, detected via IBD segments, in both ethnolinguistic populations and in large 'unrelated' populations samples has important implications for genetic genealogy, forensics and genotype/phenotype mapping studies.

  4. Plant pressure sensitive adhesives: similar chemical properties in distantly related plant lineages.

    Science.gov (United States)

    Frenzke, Lena; Lederer, Albena; Malanin, Mikhail; Eichhorn, Klaus-Jochen; Neinhuis, Christoph; Voigt, Dagmar

    2016-07-01

    A mixture of resins based on aliphatic esters and carboxylic acids occurs in distantly related genera Peperomia and Roridula , serving different functions as adhesion in seed dispersal and prey capture. According to mechanical characteristics, adhesive secretions on both leaves of the carnivorous flypaper Roridula gorgonias and epizoochorous fruits of Peperomia polystachya were expected to be similar. The chemical analysis of these adhesives turned out to be challenging because of the limited available mass for analysis. Size exclusion chromatography and Fourier transform infrared spectroscopy were suitable methods for the identification of a mixture of compounds, most appropriately containing natural resins based on aliphatic esters and carboxylic acids. The IR spectra of the Peperomia and Roridula adhesive resemble each other; they correspond to that of a synthetic ethylene-vinyl acetate copolymer, but slightly differ from that of natural tree resins. Thus, the pressure sensitive adhesive properties of the plant adhesives are chemically proved. Such adhesives seem to appear independently in distantly related plant lineages, habitats, life forms, as well as plant organs, and serve different functions such as prey capture in Roridula and fruit dispersal in Peperomia. However, more detailed chemical analyses still remain challenging because of the small available volume of plant adhesive.

  5. Bacteria may contribute to distant species recognition in ant-aphid mutualistic relationships.

    Science.gov (United States)

    Fischer, Christophe Y; Detrain, Claire; Thonart, Philippe; Haubruge, Eric; Francis, Frédéric; Verheggen, François J; Lognay, Georges C

    2017-04-01

    Mutualistic interactions between ant and aphid species have been the subject of considerable historical and contemporary investigations, the primary benefits being cleaning and protection for the aphids and carbohydrate-rich honeydew for the ants. Questions remained, however, as to the volatile semiochemical factor influencing this relationship. A recent study highlighted the role of bacterial honeydew volatile compounds in ant attraction. Here, ant's ability to distantly discriminate 2 aphid species was investigated based on bacterial honeydew semiochemicals emissions using a two-way olfactometer. Both the mutualistic aphid Aphis fabae L. and the nonmyrmecophilous aphid Acyrthosiphon pisum Harris were found to be attractive for the ant Lasius niger L. The level of attraction was similar in both assays (control vs. one of the aphid species). However, when given a choice between these 2 aphid species, ants showed a significant preference for Aphis fabae. Honeydew volatiles, mostly from bacterial origins, are known to be a key element in ant attraction. Using the same olfactometry protocol, the relative attractiveness of volatiles emitted by honeydews collected from each aphid species and by bacteria isolated from each honeydew was investigated. Again, ants significantly preferred volatiles released by Aphis fabae honeydew and bacteria. This information suggests that microbial honeydew volatiles enable ants to distantly discriminate aphid species. These results strengthen the interest of studying the occurrence and potential impact of microorganisms in insect symbioses. © 2015 Institute of Zoology, Chinese Academy of Sciences.

  6. Nano-pulse stimulation induces potent immune responses, eradicating local breast cancer while reducing distant metastases.

    Science.gov (United States)

    Guo, Siqi; Jing, Yu; Burcus, Niculina I; Lassiter, Brittany P; Tanaz, Royena; Heller, Richard; Beebe, Stephen J

    2018-02-01

    Nano-pulse stimulation (NPS) as a developing technology has been studied for minimally invasive, nonthermal local cancer elimination for more than a decade. Here we show that a single NPS treatment results in complete regression of the poorly immunogenic, metastatic 4T1-Luc mouse mammary carcinoma. Impressively, spontaneous distant organ metastases were largely prevented, even in those animals with incomplete tumor regression. All tumor-free mice were protected from secondary tumor cell challenge, demonstrating a vaccine-like effect. NPS treatment induced antitumor immunity, long-term memory T cells, destruction of tumor microenvironment and reversal of the massive increase of immune suppressor cells in the tumor microenvironment and blood. NPS-treated 4T1 cells exhibited release of damage-associated molecular patterns (DAMPs), including calreticulin, HMGB1 and ATP, and activated dendritic cells. Those findings suggest that NPS is a potent immunogenic cell death inducer that elicits antitumor immunity to prevent distant metastases in addition to local tumor eradication. © 2017 UICC.

  7. Expression of Lysyl Oxidase Predictive of Distant Metastasis of Laryngeal Cancer.

    Science.gov (United States)

    Lee, Yoon Se; Park, Yangsoon; Kwon, Minsu; Roh, Jong-Lyel; Choi, Seung-Ho; Nam, Soon Yuhl; Kim, Sang Yoon

    2017-03-01

    Objective To investigate the prognostic significance of lysyl oxidase (LOX) expression in laryngeal cancer. Study Design Retrospective chart review and histologic analysis. Setting Tertiary referral academic center. Subjects and Methods Patients (N = 100) underwent surgical treatment for laryngeal cancer and had tissue specimens available. Immunohistochemical staining for LOX was performed on laryngeal cancer tissue microarrays, and the proportion and intensity of staining were evaluated. Patients with LOX scores ≤6 were classified into the low LOX group, while those with scores >6 were classified into the high LOX group. We analyzed the correlation between LOX expression and clinical factors as well as prognosis. Results LOX was predominantly expressed in the cytoplasm and nuclei of tumor cells. Kaplan-Meier analysis revealed that the high LOX group had worse overall survival and recurrence-free survival rates than the low LOX group ( P < .05). LOX expression exhibited marginally significant correlation with lymph node metastasis. In the Cox regression analysis, LOX expression and lymph node metastasis were significant factors correlated with overall survival rate (odds ratio [OR] = 3.92, 95% confidence interval [95% CI]: 1.35-11.37, P = .012; OR = 1.96, 95% CI: 0.93-1.43, P = .024, respectively). LOX expression was related to distant metastasis free survival rate (OR = 7.72, 95% CI: 1.02-19.18, P = .048). Conclusion A high expression level of LOX is associated with lymph node and distant metastasis as well as poor prognosis among patients with laryngeal cancer.

  8. Understanding the Population of Distant Ultracool-Dwarfs from WISPS and 3d-HST

    Science.gov (United States)

    Ryan, Russell

    2013-10-01

    We are the proposing largest, most comprehensive archival campaign with HST to identify and characterize distant brown dwarfs to date. By exploiting the unprecedented sensitivity and excellent field-of-view of the WFC3/IR detector, we expect to find 110 M- and 30 L-dwarfs out to heliocentric distances of >1000 pc {for an L8-dwarf}, whereas current surveys are limited to 90% complete to J 24 and nearly 100% free of contaminating objects {such as giants, subdwarfs, or high-redshift quasars}. We have four main science goals for these ultracool dwarfs:{1} Identify ultracool dwarfs from water absorption;{2} Measure the vertical scale height as a function of spectral type;{3} Characterize the atmospheric properties of distant ultracool-dwarfs; and {4} Search for rare T/Y transition dwarfs by complete water/methane and enhanced ammonia absorption.We plan to mine 0.5 square degrees of archival grism data in G141 taken by the pure-parallel {WISPS} and the Legacy {3d-HST} surveys. Our approach represents the most efficient means of surveying these low luminosity objects at kiloparsec distances with robust spectral types.

  9. Extracting microRNA-gene relations from biomedical literature using distant supervision.

    Directory of Open Access Journals (Sweden)

    Andre Lamurias

    Full Text Available Many biomedical relation extraction approaches are based on supervised machine learning, requiring an annotated corpus. Distant supervision aims at training a classifier by combining a knowledge base with a corpus, reducing the amount of manual effort necessary. This is particularly useful for biomedicine because many databases and ontologies have been made available for many biological processes, while the availability of annotated corpora is still limited. We studied the extraction of microRNA-gene relations from text. MicroRNA regulation is an important biological process due to its close association with human diseases. The proposed method, IBRel, is based on distantly supervised multi-instance learning. We evaluated IBRel on three datasets, and the results were compared with a co-occurrence approach as well as a supervised machine learning algorithm. While supervised learning outperformed on two of those datasets, IBRel obtained an F-score 28.3 percentage points higher on the dataset for which there was no training set developed specifically. To demonstrate the applicability of IBRel, we used it to extract 27 miRNA-gene relations from recently published papers about cystic fibrosis. Our results demonstrate that our method can be successfully used to extract relations from literature about a biological process without an annotated corpus. The source code and data used in this study are available at https://github.com/AndreLamurias/IBRel.

  10. Galaxy Transformation as probed by Morphology and Velocity Fields of Distant Cluster Galaxies

    Science.gov (United States)

    Ziegler, Bodo

    2005-07-01

    We seek to obtain ACS imaging of four distant {0.3images. The velocity field and the morphology in restframe-UV light will reveal possible transformation mechanisms affecting not only the stellar populations but also the mass distribution of the galaxies. Additionally, it will be possible to pin down the nature of the interaction {e.g. tidally or ram-pressure induced}. This assessment gets supported by our N-body/SPH simulations {including star formation} of different interaction processes that allow the direct comparison of structural and kinematical characteristics at each time step with the observations on an individual basis taking into account all observational constraints for a given galaxy. All together, we will be able to explore the relative efficiency of the various proposed transformation phenomena. In the case of non-disturbed spirals, a rotation curve can be extracted from the full 2D velocity field with unprecedented quality, from which the maximum rotation speed can be derived with high confidence. In combination with accurate size and luminosity determinations from the ACS images, we will be able to establish the Tully-Fisher and Fundamental Plane relations of cluster spiral members at cosmological epochs. At these distances cluster assembly is predicted to peak and we can probe the galaxies' luminosity, size and mass evolution with robust methods. Together with our already existing sample of 200 distant {z<=1} spiral galaxies in the field, we will put strong constraints on current theories of galaxy formation and evolution in different environments.

  11. Overexpression of c-Myb is associated with suppression of distant metastases in colorectal carcinoma.

    Science.gov (United States)

    Tichý, Michal; Knopfová, Lucia; Jarkovský, Jiří; Pekarčíková, Lucie; Veverková, Lenka; Vlček, Petr; Katolická, Jana; Čapov, Ivan; Hermanová, Markéta; Šmarda, Jan; Beneš, Petr

    2016-08-01

    The MYB gene codes for the c-Myb transcription factor maintaining proliferation of colon epithelial progenitors, thus controlling colon development and homeostasis. This gene is overexpressed in early phases of colorectal cancer (CRC) tumorigenesis. The aim of this study was to examine the expression of c-Myb in CRC tissue samples both at the messenger RNA (mRNA) and protein levels and to evaluate their associations with clinicopathological characteristics in a group of 108 CRC patients. Statistically significant negative association was found between the frequency of the c-Myb-positive tumor cells assessed by immunohistochemistry and the presence of distant metastases (p Myb protein level in the tumor tissue correlated with its mRNA level, no significant association between MYB mRNA and any clinicopathological characteristics was observed. We conclude that albeit overexpression of c-Myb is considered as an important factor contributing to early phases of CRC tumorigenesis, it may later have negative effect on tumor cell dissemination as observed recently in breast cancer as well. Further studies are required to explain the role of c-Myb during formation of CRC distant metastases.

  12. Exploring the Structure of the Distant Universe with MUSE Data Cubes

    Science.gov (United States)

    MacDougall, Mason; Christensen, Lise

    2018-01-01

    The mass distribution in intergalactic and circumgalactic space is not well known since it is difficult to characterize objects in the distant universe. An ideal tool for studying such distant structure is the Multi-Unit Spectroscopic Explorer (MUSE) of the Very Large Telescope array, which employs a wide field-of-view and a large spectral range to produce high spatial resolution datasets. Here we exploit the 2 spatial dimensions and 1 spectral dimension of a particular MUSE “data cube” to identify and characterize emission line sources near the line-of-sight to quasar PKS1937-101, which lies at a redshift of z=3.787. In particular, we search for galaxy companions to a z=3.572 Lyman-limit system measured in the quasar spectrum and find an associated Lyman-alpha emitter at z=3.556 with a projected distance of 30.2 kpc from the quasar line-of-sight. Through a combination of automated source extraction and manual investigation, we also identify 25 emission line galaxies and 1 other Lyman-alpha emitter in our field. The proximity of several of these objects to the quasar line-of-sight allows us to reliably identify absorption lines in the quasar spectrum that can be associated with observed emission lines with resolved fluxes. This will help characterize the metallicities and kinematics of galaxy halos and circumgalactic media in the early universe.

  13. Electric coupling between distant nitrate reduction and sulfide oxidation in marine sediment.

    Science.gov (United States)

    Marzocchi, Ugo; Trojan, Daniela; Larsen, Steffen; Meyer, Rikke Louise; Revsbech, Niels Peter; Schramm, Andreas; Nielsen, Lars Peter; Risgaard-Petersen, Nils

    2014-08-01

    Filamentous bacteria of the Desulfobulbaceae family can conduct electrons over centimeter-long distances thereby coupling oxygen reduction at the surface of marine sediment to sulfide oxidation in deeper anoxic layers. The ability of these cable bacteria to use alternative electron acceptors is currently unknown. Here we show that these organisms can use also nitrate or nitrite as an electron acceptor thereby coupling the reduction of nitrate to distant oxidation of sulfide. Sulfidic marine sediment was incubated with overlying nitrate-amended anoxic seawater. Within 2 months, electric coupling of spatially segregated nitrate reduction and sulfide oxidation was evident from: (1) the formation of a 4-6-mm-deep zone separating sulfide oxidation from the associated nitrate reduction, and (2) the presence of pH signatures consistent with proton consumption by cathodic nitrate reduction, and proton production by anodic sulfide oxidation. Filamentous Desulfobulbaceae with the longitudinal structures characteristic of cable bacteria were detected in anoxic, nitrate-amended incubations but not in anoxic, nitrate-free controls. Nitrate reduction by cable bacteria using long-distance electron transport to get privileged access to distant electron donors is a hitherto unknown mechanism in nitrogen and sulfur transformations, and the quantitative importance for elements cycling remains to be addressed.

  14. Nuclear magnetic resonance signal dynamics of liquids in the presence of distant dipolar fields, revisited.

    Science.gov (United States)

    Barros, Wilson; Gochberg, Daniel F; Gore, John C

    2009-05-07

    The description of the nuclear magnetic resonance magnetization dynamics in the presence of long-range dipolar interactions, which is based upon approximate solutions of Bloch-Torrey equations including the effect of a distant dipolar field, has been revisited. New experiments show that approximate analytic solutions have a broader regime of validity as well as dependencies on pulse-sequence parameters that seem to have been overlooked. In order to explain these experimental results, we developed a new method consisting of calculating the magnetization via an iterative formalism where both diffusion and distant dipolar field contributions are treated as integral operators incorporated into the Bloch-Torrey equations. The solution can be organized as a perturbative series, whereby access to higher order terms allows one to set better boundaries on validity regimes for analytic first-order approximations. Finally, the method legitimizes the use of simple analytic first-order approximations under less demanding experimental conditions, it predicts new pulse-sequence parameter dependencies for the range of validity, and clarifies weak points in previous calculations.

  15. The Prader-Willi syndrome murine imprinting center is not involved in the spatio-temporal transcriptional regulation of the Necdin gene

    Directory of Open Access Journals (Sweden)

    Dandolo Luisa

    2005-01-01

    Full Text Available Abstract Background The human Prader-Willi syndrome (PWS domain and its mouse orthologue include a cluster of paternally expressed genes which imprinted expression is co-ordinately regulated by an imprinting center (IC closely associated to the Snurf-Snrpn gene. Besides their co-regulated imprinted expression, two observations suggest that the spatio-temporal expression of these genes could also be co-regulated. First, the PWS genes have all been reported to be expressed in the mouse nervous system. Second, Snurf-Snrpn and its associated IC are the most ancient elements of the domain which later acquired additional functional genes by retrotransposition. Although located at least 1.5 megabases from the IC, these retroposons acquired the same imprinted regulation as Snurf-Snrpn. In this study, we ask whether the IC, in addition to its function in imprinting, could also be involved in the spatio-temporal regulation of genes in the PWS domain. Results We compared the expression pattern of Snurf-Snrpn and C/D-box small nucleolar RNAs (snoRNAs MBII-85 and MBII-52 to the expression pattern of the two evolutionary related retroposons Ndn and Magel2, in the developing mouse embryo. We show that these genes have highly similar expression patterns in the central nervous system, suggesting that they share a common central nervous system-specific regulatory element. Among these genes, Ndn and Magel2 display the most similar expression patterns. Using transgenic mice containing the Ndn and Magel2 genes, we show that the transgenic Ndn gene whereas not imprinted is correctly expressed. Search for DNase I hypersensitive sites in the Ndn-Magel2 genomic region and comparative genomic analyses were performed in order to identify potential transcriptional cis-regulatory elements. Conclusions These results strongly suggest that paternally expressed genes of the PWS domain share a common central nervous system-specific regulatory element. We proposed that this

  16. An Evolutionary Explanation for the Perturbation of the Dynamics of Metastatic Tumors Induced by Surgery and Acute Inflammation

    Energy Technology Data Exchange (ETDEWEB)

    Bayonas, Alberto Carmona [Department of Hematology and Medical Oncology, Hospital Morales Meseguer, Murcia (Spain)

    2011-03-02

    Surgery has contributed to unveil a tumor behavior that is difficult to reconcile with the models of tumorigenesis based on gradualism. The postsurgical patterns of progression include unexpected features such as distant interactions and variable rhythms. The underlying evidence can be summarized as follows: (1) the resection of the primary tumor is able to accelerate the evolution of micrometastasis in early stages, and (2) the outcome is transiently opposed in advanced tumors. The objective of this paper is to give some insight into tumorigenesis and surgery-related effects, by applying the concepts of the evolutionary theory in those tumor behaviors that gompertzian and tissular-centered models are unable to explain. According to this view, tumors are the consequence of natural selection operating at the somatic level, which is the basic mechanism of tumorigenesis, notwithstanding the complementary role of the intrinsic constrictions of complex networks. A tumor is a complicated phenomenon that entails growth, evolution and development simultaneously. So, an evo-devo perspective can explain how and why tumor subclones are able to translate competition from a metabolic level into neoangiogenesis and the immune response. The paper proposes that distant interactions are an extension of the ecological events at the local level. This notion explains the evolutionary basis for tumor dormancy, and warns against the teleological view of tumorigenesis as a process directed towards the maximization of a concrete trait such as aggressiveness.

  17. ADHD and temporality

    DEFF Research Database (Denmark)

    Nielsen, Mikka

    According to the official diagnostic manual, ADHD is defined by symptoms of inattention, hyperactivity, and impulsivity and patterns of behaviour are characterized as failure to pay attention to details, excessive talking, fidgeting, or inability to remain seated in appropriate situations (DSM-5......). In this paper, however, I will ask if we can understand what we call ADHD in a different way than through the symptom descriptions and will advocate for a complementary, phenomenological understanding of ADHD as a certain being in the world – more specifically as a matter of a phenomenological difference...... in temporal experience and/or rhythm. Inspired by both psychiatry’s experiments with people diagnosed with ADHD and their assessment of time and phenomenological perspectives on mental disorders and temporal disorientation I explore the experience of ADHD as a disruption in the phenomenological experience...

  18. Temporal lobe epilepsy semiology.

    Science.gov (United States)

    Blair, Robert D G

    2012-01-01

    Epilepsy represents a multifaceted group of disorders divided into two broad categories, partial and generalized, based on the seizure onset zone. The identification of the neuroanatomic site of seizure onset depends on delineation of seizure semiology by a careful history together with video-EEG, and a variety of neuroimaging technologies such as MRI, fMRI, FDG-PET, MEG, or invasive intracranial EEG recording. Temporal lobe epilepsy (TLE) is the commonest form of focal epilepsy and represents almost 2/3 of cases of intractable epilepsy managed surgically. A history of febrile seizures (especially complex febrile seizures) is common in TLE and is frequently associated with mesial temporal sclerosis (the commonest form of TLE). Seizure auras occur in many TLE patients and often exhibit features that are relatively specific for TLE but few are of lateralizing value. Automatisms, however, often have lateralizing significance. Careful study of seizure semiology remains invaluable in addressing the search for the seizure onset zone.

  19. Useful parasites: the evolutionary biology and biotechnology ...

    Indian Academy of Sciences (India)

    , transposable elements have long been considered as 'parasitic' or 'selfish'. Today, we ... research niche and deserve to be included into the agenda of molecular ecologists, evolutionary geneticists, conservation biologists and plant breeders.

  20. Evolutionary history of dog rabies in Brazil

    National Research Council Canada - National Science Library

    Kobayashi, Yuki; Suzuki, Yoshiyuki; Itou, Takuya; Ito, Fumio H; Sakai, Takeo; Gojobori, Takashi

    2011-01-01

    .... In order to investigate the evolutionary history of dog rabies virus (RABV) in Brazil, we performed a phylogenetic analysis of carnivore RABV isolates from around the world and estimated the divergence times for dog RABV in Brazil...

  1. Evolutionary algorithms for mobile ad hoc networks

    CERN Document Server

    Dorronsoro, Bernabé; Danoy, Grégoire; Pigné, Yoann; Bouvry, Pascal

    2014-01-01

    Describes how evolutionary algorithms (EAs) can be used to identify, model, and minimize day-to-day problems that arise for researchers in optimization and mobile networking. Mobile ad hoc networks (MANETs), vehicular networks (VANETs), sensor networks (SNs), and hybrid networks—each of these require a designer’s keen sense and knowledge of evolutionary algorithms in order to help with the common issues that plague professionals involved in optimization and mobile networking. This book introduces readers to both mobile ad hoc networks and evolutionary algorithms, presenting basic concepts as well as detailed descriptions of each. It demonstrates how metaheuristics and evolutionary algorithms (EAs) can be used to help provide low-cost operations in the optimization process—allowing designers to put some “intelligence” or sophistication into the design. It also offers efficient and accurate information on dissemination algorithms topology management, and mobility models to address challenges in the ...

  2. Evolutionary biology of centipedes (Myriapoda: Chilopoda).

    Science.gov (United States)

    Edgecombe, Gregory D; Giribet, Gonzalo

    2007-01-01

    New insights into the anatomy, systematics, and biogeography of centipedes have put these predatory terrestrial arthropods at the forefront of evolutionary studies. Centipedes have also played a pivotal role in understanding high-level arthropod relationships. Their deep evolutionary history, with a fossil record spanning 420 million years, explains their current worldwide distribution. Recent analyses of combined morphological and molecular data provide a stable phylogeny that underpins evolutionary interpretations of their biology. The centipede trunk, with its first pair of legs modified into a venom-delivering organ followed by 15 to 191 leg pairs, is a focus of arthropod segmentation studies. Gene expression studies and phylogenetics shed light on key questions in evolutionary developmental biology concerning the often group-specific fixed number of trunk segments, how some centipedes add segments after hatching whereas others hatch with the complete segment count, the addition of segments through evolution, and the invariably odd number of leg-bearing trunk segments.

  3. Hybridizing Evolutionary Algorithms with Opportunistic Local Search

    DEFF Research Database (Denmark)

    Gießen, Christian

    2013-01-01

    There is empirical evidence that memetic algorithms (MAs) can outperform plain evolutionary algorithms (EAs). Recently the first runtime analyses have been presented proving the aforementioned conjecture rigorously by investigating Variable-Depth Search, VDS for short (Sudholt, 2008). Sudholt...

  4. A Philosophical Perspective on Evolutionary Systems Biology.

    Science.gov (United States)

    O'Malley, Maureen A; Soyer, Orkun S; Siegal, Mark L

    2015-03-01

    Evolutionary systems biology (ESB) is an emerging hybrid approach that integrates methods, models, and data from evolutionary and systems biology. Drawing on themes that arose at a cross-disciplinary meeting on ESB in 2013, we discuss in detail some of the explanatory friction that arises in the interaction between evolutionary and systems biology. These tensions appear because of different modeling approaches, diverse explanatory aims and strategies, and divergent views about the scope of the evolutionary synthesis. We locate these discussions in the context of long-running philosophical deliberations on explanation, modeling, and theoretical synthesis. We show how many of the issues central to ESB's progress can be understood as general philosophical problems. The benefits of addressing these philosophical issues feed back into philosophy too, because ESB provides excellent examples of scientific practice for the development of philosophy of science and philosophy of biology.

  5. Evolutionary origins of leadership and followership.

    Science.gov (United States)

    Van Vugt, Mark

    2006-01-01

    Drawing upon evolutionary logic, leadership is reconceptualized in terms of the outcome of strategic interactions among individuals who are following different, yet complementary, decision rules to solve recurrent coordination problems. This article uses the vast psychological literature on leadership as a database to test several evolutionary hypotheses about the origins of leadership and followership in humans. As expected, leadership correlates with initiative taking, trait measures of intelligence, specific task competencies, and several indicators of generosity. The review finds no link between leadership and dominance. The evolutionary analysis accounts for reliable age, health, and sex differences in leadership emergence. In general, evolutionary theory provides a useful, integrative framework for studying leader-follower relationships and generates various novel research hypotheses.

  6. Evolutionary medicine: its scope, interest and potential.

    Science.gov (United States)

    Stearns, Stephen C

    2012-11-07

    This review is aimed at readers seeking an introductory overview, teaching courses and interested in visionary ideas. It first describes the range of topics covered by evolutionary medicine, which include human genetic variation, mismatches to modernity, reproductive medicine, degenerative disease, host-pathogen interactions and insights from comparisons with other species. It then discusses priorities for translational research, basic research and health management. Its conclusions are that evolutionary thinking should not displace other approaches to medical science, such as molecular medicine and cell and developmental biology, but that evolutionary insights can combine with and complement established approaches to reduce suffering and save lives. Because we are on the cusp of so much new research and innovative insights, it is hard to estimate how much impact evolutionary thinking will have on medicine, but it is already clear that its potential is enormous.

  7. Complex evolutionary systems in behavioral finance

    NARCIS (Netherlands)

    Hommes, C.; Wagener, F.

    2008-01-01

    Traditional finance is built on the rationality paradigm. This chapter discusses simple models from an alternative approach in which financial markets are viewed as complex evolutionary systems. Agents are boundedly rational and base their investment decisions upon market forecasting heuristics.

  8. Mean-Potential Law in Evolutionary Games

    Science.gov (United States)

    Nałecz-Jawecki, Paweł; Miekisz, Jacek

    2018-01-01

    The Letter presents a novel way to connect random walks, stochastic differential equations, and evolutionary game theory. We introduce a new concept of a potential function for discrete-space stochastic systems. It is based on a correspondence between one-dimensional stochastic differential equations and random walks, which may be exact not only in the continuous limit but also in finite-state spaces. Our method is useful for computation of fixation probabilities in discrete stochastic dynamical systems with two absorbing states. We apply it to evolutionary games, formulating two simple and intuitive criteria for evolutionary stability of pure Nash equilibria in finite populations. In particular, we show that the 1 /3 law of evolutionary games, introduced by Nowak et al. [Nature, 2004], follows from a more general mean-potential law.

  9. Evolutionary Theories of Aging and Longevity

    Directory of Open Access Journals (Sweden)

    Leonid A. Gavrilov

    2002-01-01

    Full Text Available The purpose of this article is to provide students and researchers entering the field of aging studies with an introduction to the evolutionary theories of aging, as well as to orient them in the abundant modern scientific literature on evolutionary gerontology. The following three major evolutionary theories of aging are discussed: 1 the theory of programmed death suggested by August Weismann, 2 the mutation accumulation theory of aging suggested by Peter Medawar, and 3 the antagonistic pleiotropy theory of aging suggested by George Williams. We also discuss a special case of the antagonistic pleiotropy theory, the disposable soma theory developed by Tom Kirkwood and Robin Holliday. The theories are compared with each other as well as with recent experimental findings. At present the most viable evolutionary theories are the mutation accumulation theory and the antagonistic pleiotropy theory; these theories are not mutually exclusive, and they both may become a part of a future unifying theory of aging.

  10. An evolutionary basis for pollination ecology

    OpenAIRE

    Willemstein, S.C.

    1987-01-01

    In the introduction and chapter 2 the incentives and way of reasoning are given for the description of an evolutionary basis of pollination ecology. Starting from the until recently rather anecdotical character of the study of pollination ecology as a whole, and in the absence of large-scale correlations of flowerecologically important character states with angiosperm and insect phylogeny (in the sense of Hennig, 1966), an attempt is made to derive directed evolutionary lines (transformation ...

  11. Financial Markets as Nonlinear Adaptive Evolutionary Systems

    OpenAIRE

    Hommes, C.H.

    2001-01-01

    This paper gives an overview of joint work with Buz Brock, on evolutionary adaptive belief systems (ABS) for modelling financial markets. Recent work with Andrea Gaunersdorfer is also reviewed and some recent experimental work on expectation formation in financial markets is also discussed. Financial markets are viewed as evolutionary systems between different, competing trading strategies. Agents are boundedly rational in the sense that they tend to follow strategies that have performed well...

  12. An evolutionary behaviorist perspective on orgasm

    OpenAIRE

    Fleischman, Diana S

    2016-01-01

    Evolutionary explanations for sexual behavior and orgasm most often posit facilitating reproduction as the primary function (i.e. greater rate of fertilization). Other reproductive benefits of sexual pleasure and orgasm such as improved bonding of parents have also been discussed but not thoroughly. Although sex is known to be highly reinforcing, behaviorist principles are rarely invoked alongside evolutionary psychology in order to account for human sexual and social behavior. In this paper,...

  13. Evolutionary scenarios of Notch proteins.

    Science.gov (United States)

    Theodosiou, Athina; Arhondakis, Stilianos; Baumann, Marc; Kossida, Sophia

    2009-07-01

    Notch is a highly conserved family of transmembrane receptors and transcription factors that are key players in several developmental processes. In this study, we identified novel Notch sequences from various species covering from worm to human and conducted a comprehensive phylogenetic analysis in order to confirm and extend the evolutionary history of Notch. Our findings confirm an independent duplication event in Caenorhabditis elegans resulting in two Notch genes and show that the vertebrate Notch genes resulted from two duplication events, both of which occurred before the divergence of teleosts and tetrapoda. Furthermore, we demonstrate that the vertebrate Notch2 group is phylogenetically closer to Notch3 and that Notch2 appeared at the first round of vertebrate duplication events. Moreover, there is evidence that the two Notch1 genes in fish, appeared by a recent duplication of Notch1 in teleost after the divergence of teleost and tetrapoda. Whether this is from ancient whole genome duplication (WGD) or gene duplication remains to be elucidated. The fourth group of Notch (Notch4) was found only in mammals. We suggest two possible scenarios for the origin of the Notch4 subfamily: 1) Notch4 appeared at the time of the two WGDs in the early chordate but has been maintained only in the mammalian lineage and was lost in the other lineages, 2) a recent independent duplication event took place in the mammalian lineage. The increase of the sequencing data from Xenopus tropicalis, Gallus gallus genome projects and of other avian and reptile genomes will shed more light on this event. Nevertheless, the great divergence of Notch4, from the other three Notch genes, suggests a rapid divergence raising questions about the functional implication of this event. In addition, comparison of the organization of Notch syntenic genes among species supports the coordinated rearrangements during evolution for Ntch, PBX, and BRD families that may lead to possible functional

  14. [Evolutionary Concept Analysis of Spirituality].

    Science.gov (United States)

    Ko, Il Sun; Choi, So Young; Kim, Jin Sook

    2017-04-01

    This study was done to clarify attributes, antecedents, and consequences of spirituality. Rodgers's evolutionary concept analysis was used to analyze fifty seven studies from the literature related to spirituality as it appears in systematic literature reviews of theology, medicine, counseling & psychology, social welfare, and nursing. Spirituality was found to consist of two dimensions and eight attributes: 1) vertical dimension: 'intimacy and connectedness with God' and 'holy life and belief', 2) horizontal dimension: 'self-transcendence', 'meaning and purpose in life', 'self-integration', and 'self-creativity' in relationship with self, 'connectedness' and 'trust' in relationship with others·neighbors·nature. Antecedents of spirituality were socio-demographic, religious, psychological, and health related characteristics. Consequences of spirituality were positive and negative. Being positive included 'life centered on God' in vertical dimension, and among horizontal dimension 'joy', 'hope', 'wellness', 'inner peace', and 'self-actualization' in relationship with self, 'doing in love' and 'extended life toward neighbors and the world' in relationship with others·neighbors·nature. Being negative was defined as having 'guilt', 'inner conflict', 'loneliness', and 'spiritual distress'. Facilitators of spirituality were stressful life events and experiences. Spirituality is a multidimensional concept. Unchangeable attributes of spirituality are 'connectedness with God', 'self-transcendence', 'meaning of life' and 'connectedness with others·nature'. Unchangeable consequences of spirituality are 'joy' and 'hope'. The findings suggest that the dimensional framework of spirituality can be used to assess the current spiritual state of patients. Based on these results, the development of a Korean version of the scale measuring spirituality is recommended.

  15. Distant Metastasis Risk Stratification for Patients Undergoing Curative Resection Followed by Adjuvant Chemoradiation for Extrahepatic Bile Duct Cancer

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Kyubo [Department of Radiation Oncology, Seoul National University College of Medicine, Seoul (Korea, Republic of); Chie, Eui Kyu, E-mail: ekchie93@snu.ac.kr [Department of Radiation Oncology, Seoul National University College of Medicine, Seoul (Korea, Republic of); Jang, Jin-Young; Kim, Sun Whe [Department of Surgery, Seoul National University College of Medicine, Seoul (Korea, Republic of); Han, Sae-Won; Oh, Do-Youn; Im, Seock-Ah; Kim, Tae-You; Bang, Yung-Jue [Department of Internal Medicine, Seoul National University College of Medicine, Seoul (Korea, Republic of); Ha, Sung W. [Department of Radiation Oncology, Seoul National University College of Medicine, Seoul (Korea, Republic of); Institute of Radiation Medicine, Medical Research Center, Seoul National University (Korea, Republic of)

    2012-09-01

    Purpose: To analyze the prognostic factors predicting distant metastasis in patients undergoing adjuvant chemoradiation for extrahepatic bile duct (EHBD) cancer. Methods and Materials: Between January 1995 and August 2006, 166 patients with EHBD cancer underwent resection with curative intent, followed by adjuvant chemoradiation. There were 120 males and 46 females, and median age was 61 years (range, 34-86). Postoperative radiotherapy was delivered to tumor bed and regional lymph nodes (median dose, 40 Gy; range, 34-56 Gy). A total of 157 patients also received fluoropyrimidine chemotherapy as a radiosensitizer, and fluoropyrimidine-based maintenance chemotherapy was administered to 127 patients. Median follow-up duration was 29 months. Results: The treatment failed for 97 patients, and the major pattern of failure was distant metastasis (76 patients, 78.4%). The 5-year distant metastasis-free survival rate was 49.4%. The most common site of distant failure was the liver (n = 36). On multivariate analysis, hilar tumor, tumor size {>=}2 cm, involved lymph node, and poorly differentiated tumor were associated with inferior distant metastasis-free survival (p = 0.0348, 0.0754, 0.0009, and 0.0078, respectively), whereas T stage was not (p = 0.8081). When patients were divided into four groups based on these risk factors, the 5-year distant metastasis-free survival rates for patients with 0, 1, 2, and 3 risk factors were 86.4%, 59.9%, 32.5%, and 0%, respectively (p < 0.0001). Conclusion: Despite maintenance chemotherapy, distant metastasis was the major pattern of failure in patients undergoing adjuvant chemoradiation for EHBD cancer after resection with curative intent. Intensified chemotherapy is warranted to improve the treatment outcome, especially in those with multiple risk factors.

  16. Why an extended evolutionary synthesis is necessary.

    Science.gov (United States)

    Müller, Gerd B

    2017-10-06

    Since the last major theoretical integration in evolutionary biology-the modern synthesis (MS) of the 1940s-the biosciences have made significant advances. The rise of molecular biology and evolutionary developmental biology, the recognition of ecological development, niche construction and multiple inheritance systems, the '-omics' revolution and the science of systems biology, among other developments, have provided a wealth of new knowledge about the factors responsible for evolutionary change. Some of these results are in agreement with the standard theory and others reveal different properties of the evolutionary process. A renewed and extended theoretical synthesis, advocated by several authors in this issue, aims to unite pertinent concepts that emerge from the novel fields with elements of the standard theory. The resulting theoretical framework differs from the latter in its core logic and predictive capacities. Whereas the MS theory and its various amendments concentrate on genetic and adaptive variation in populations, the extended framework emphasizes the role of constructive processes, ecological interactions and systems dynamics in the evolution of organismal complexity as well as its social and cultural conditions. Single-level and unilinear causation is replaced by multilevel and reciprocal causation. Among other consequences, the extended framework overcomes many of the limitations of traditional gene-centric explanation and entails a revised understanding of the role of natural selection in the evolutionary process. All these features stimulate research into new areas of evolutionary biology.

  17. Pulmonary CT image classification with evolutionary programming.

    Science.gov (United States)

    Madsen, M T; Uppaluri, R; Hoffman, E A; McLennan, G

    1999-12-01

    It is often difficult to classify information in medical images from derived features. The purpose of this research was to investigate the use of evolutionary programming as a tool for selecting important features and generating algorithms to classify computed tomographic (CT) images of the lung. Training and test sets consisting of 11 features derived from multiple lung CT images were generated, along with an indicator of the target area from which features originated. The images included five parameters based on histogram analysis, 11 parameters based on run length and co-occurrence matrix measures, and the fractal dimension. Two classification experiments were performed. In the first, the classification task was to distinguish between the subtle but known differences between anterior and posterior portions of transverse lung CT sections. The second classification task was to distinguish normal lung CT images from emphysematous images. The performance of the evolutionary programming approach was compared with that of three statistical classifiers that used the same training and test sets. Evolutionary programming produced solutions that compared favorably with those of the statistical classifiers. In separating the anterior from the posterior lung sections, the evolutionary programming results were better than two of the three statistical approaches. The evolutionary programming approach correctly identified all the normal and abnormal lung images and accomplished this by using less features than the best statistical method. The results of this study demonstrate the utility of evolutionary programming as a tool for developing classification algorithms.

  18. Evolutionary theories of aging and longevity.

    Science.gov (United States)

    Gavrilov, Leonid A; Gavrilova, Natalia S

    2002-02-07

    The purpose of this article is to provide students and researchers entering the field of aging studies with an introduction to the evolutionary theories of aging, as well as to orient them in the abundant modern scientific literature on evolutionary gerontology. The following three major evolutionary theories of aging are discussed: 1) the theory of programmed death suggested by August Weismann, 2) the mutation accumulation theory of aging suggested by Peter Medawar, and 3) the antagonistic pleiotropy theory of aging suggested by George Williams. We also discuss a special case of the antagonistic pleiotropy theory, the disposable soma theory developed by Tom Kirkwood and Robin Holliday. The theories are compared with each other as well as with recent experimental findings. At present the most viable evolutionary theories are the mutation accumulation theory and the antagonistic pleiotropy theory; these theories are not mutually exclusive, and they both may become a part of a future unifying theory of aging. Evolutionary theories of aging are useful because they open new opportunities for further research by suggesting testable predictions, but they have also been harmful in the past when they were used to impose limitations on aging studies. At this time, the evolutionary theories of aging are not ultimate completed theories, but rather a set of ideas that themselves require further elaboration and validation. This theoretical review article is written for a wide readership.

  19. Characterizing behavioural 'characters': an evolutionary framework.

    Science.gov (United States)

    Araya-Ajoy, Yimen G; Dingemanse, Niels J

    2014-02-07

    Biologists often study phenotypic evolution assuming that phenotypes consist of a set of quasi-independent units that have been shaped by selection to accomplish a particular function. In the evolutionary literature, such quasi-independent functional units are called 'evolutionary characters', and a framework based on evolutionary principles has been developed to characterize them. This framework mainly focuses on 'fixed' characters, i.e. those that vary exclusively between individuals. In this paper, we introduce multi-level variation and thereby expand the framework to labile characters, focusing on behaviour as a worked example. We first propose a concept of 'behavioural characters' based on the original evolutionary character concept. We then detail how integration of variation between individuals (cf. 'personality') and within individuals (cf. 'individual plasticity') into the framework gives rise to a whole suite of novel testable predictions about the evolutionary character concept. We further propose a corresponding statistical methodology to test whether observed behaviours should be considered expressions of a hypothesized evolutionary character. We illustrate the application of our framework by characterizing the behavioural character 'aggressiveness' in wild great tits, Parus major.

  20. Evolutionary cell biology: two origins, one objective.

    Science.gov (United States)

    Lynch, Michael; Field, Mark C; Goodson, Holly V; Malik, Harmit S; Pereira-Leal, José B; Roos, David S; Turkewitz, Aaron P; Sazer, Shelley

    2014-12-02

    All aspects of biological diversification ultimately trace to evolutionary modifications at the cellular level. This central role of cells frames the basic questions as to how cells work and how cells come to be the way they are. Although these two lines of inquiry lie respectively within the traditional provenance of cell biology and evolutionary biology, a comprehensive synthesis of evolutionary and cell-biological thinking is lacking. We define evolutionary cell biology as the fusion of these two eponymous fields with the theoretical and quantitative branches of biochemistry, biophysics, and population genetics. The key goals are to develop a mechanistic understanding of general evolutionary processes, while specifically infusing cell biology with an evolutionary perspective. The full development of this interdisciplinary field has the potential to solve numerous problems in diverse areas of biology, including the degree to which selection, effectively neutral processes, historical contingencies, and/or constraints at the chemical and biophysical levels dictate patterns of variation for intracellular features. These problems can now be examined at both the within- and among-species levels, with single-cell methodologies even allowing quantification of variation within genotypes. Some results from this emerging field have already had a substantial impact on cell biology, and future findings will significantly influence applications in agriculture, medicine, environmental science, and synthetic biology.