WorldWideScience

Sample records for assimilating assorted acquaintance

  1. VirusPKT: A Search Tool For Assimilating Assorted Acquaintance For Viruses

    CERN Document Server

    Manicassamy, Jayanthi

    2009-01-01

    Viruses utilize various means to circumvent the immune detection in the biological systems. Several mathematical models have been investigated for the description of viral dynamics in the biological system of human and various other species. One common strategy for evasion and recognition of viruses is, through acquaintance in the systems by means of search engines. In this perspective a search tool have been developed to provide a wider comprehension about the structure and other details on viruses which have been narrated in this paper. This provides an adequate knowledge in evolution and building of viruses, its functions through information extraction from various websites. Apart from this, tool aim to automate the activities associated with it in a self-maintainable, self-sustainable, proactive one which has been evaluated through analysis made and have been discussed in this paper.

  2. VirusPKT: A Search Tool For Assimilating Assorted Acquaintance For Viruses

    Directory of Open Access Journals (Sweden)

    Jayanthi Manicassamy

    2009-11-01

    Full Text Available Viruses utilize various means to circumvent the immune detection in the biological systems. Several mathematical models have been investigated for the description of viral dynamics in the biological system of human and various other species. One common strategy for evasion and recognition of viruses is, through acquaintance in the systems by means of search engines. In this perspective a search tool have been developed to provide a wider comprehension about the structure and other details on viruses which have been narrated in this paper. This provides an adequate knowledge in evolution and building of viruses, its functions through information extraction from various websites. Apart from this, tool aim to automate the activities associated with it in a self-maintainable, self-sustainable, proactive one which has been evaluated through analysis made and have been discussed in this paper.

  3. Leveling the Playing Field: Longer Acquaintance Predicts Reduced Assortative Mating on Attractiveness.

    Science.gov (United States)

    Hunt, Lucy L; Eastwick, Paul W; Finkel, Eli J

    2015-07-01

    Clear empirical demonstrations of the theoretical principles underlying assortative mating remain elusive. This article examines a moderator of assortative mating--how well couple members knew each other before dating--suggested by recent findings related to market-based (i.e., competition) theories. Specifically, competition is pervasive to the extent that people achieve consensus about who possesses desirable qualities (e.g., attractiveness) and who does not. Because consensus is stronger earlier in the acquaintance process, assortative mating based on attractiveness should be stronger among couples who formed a relationship after a short period rather than a long period of acquaintance. A study of 167 couples included measures of how long partners had known each other before dating and whether they had been friends before dating, as well as coders' ratings of physical attractiveness. As predicted, couples revealed stronger evidence of assortative mating to the extent that they knew each other for a short time and were not friends before initiating a romantic relationship. PMID:26068893

  4. How acquainting shows verbally

    DEFF Research Database (Denmark)

    Hermann, Jesper

    2004-01-01

    A central tenet of the integrational view of language and communication is an anchoring in the acting and integrating behaviour of the communicants themselves. In this way the integrational approach has a certain phenomenological slant. What happens when this approach is combined with a ¿psychology...... of linguistic exertion¿ based upon the descriptions of the  stream of thought, and of conception (>acquainting) by William James? Text-examples taken from an internet site for dieters illustrate the combined James'ian & integrational approach in practice. Some of the examples are also specifically related...

  5. Optimizing Retail Assortments

    NARCIS (Netherlands)

    Rooderkerk, Robert P.; van Heerde, Harald J.; Bijmolt, Tammo H. A.

    2013-01-01

    Retailers face the problem of finding the assortment that maximizes category profit. This is a challenging task because the number. of potential assortments is very large when there are many stock-keeping units (SKUs) to choose from. Moreover, SKIT sales can be cannibalized by other SKUs in the asso

  6. Acquaintance Rape: Effective Avoidance Strategies.

    Science.gov (United States)

    Levine-MacCombie, Joyce; Koss, Mary P.

    1986-01-01

    Determined that acknowledged and unacknowledged acquaintance rape victims and rape avoiders could be discriminated by situational variables and response strategies. Avoiders were less likely to have experienced passive or internalizing emotions at the time of the assault, perceived the assault as less violent, and were more likely to have utilized…

  7. Risk Appraisal in Scripted Acquaintance Rape Scenarios.

    Science.gov (United States)

    Wright, Doris J.

    Cognitive appraisals are believed to influence how women judge or appraise risk in acquaintance interactions which lead to sexual assault. Ways in which men and women judge the presence of risk factors in scripted acquaintance rape scenarios, and whether alcohol was a significant factor in assessing risk, are examined in this paper. Participants…

  8. Campus Acquaintance Rape: An Ethical Analysis.

    Science.gov (United States)

    Haggard, William K.

    1992-01-01

    Introduces idea of including ethics in acquaintance rape prevention programming. Applies education model for ethical analysis of sexual behavior to problem of acquaintance rape among college and university students to provide practitioners with new insights which will motivate inclusion of moral and ethical objectives in future prevention…

  9. Reactions to Stranger and Acquaintance Rape.

    Science.gov (United States)

    Tetreault, Patricia A.; Barnett, Mark A.

    1987-01-01

    Investigated reactions to a woman who presumably had been raped by a stranger or an acquaintance. Undergraduates read one of two rape descriptions prior to watching a videotape of the woman who (they were led to believe) had been the victim of the rape. Females and males showed markedly different reactions to stranger and acquaintance rape and…

  10. Acquaintance Rape on Campus: A Literature Review.

    Science.gov (United States)

    Benson, Dennis; And Others

    1992-01-01

    Examines issues related to acquaintance rape: cultural context, legal issues, adolescent attitudes and development, alcohol and sexual assault, the assailants, the victims, and the institutional response, and makes recommendations for a system that all colleges should have in place. (SM)

  11. Chromosome assortment in Saccharum.

    Science.gov (United States)

    Al-Janabi, S M; Honeycutt, R J; Sobral, B W

    1994-12-01

    Recent work has revealed random chromosome pairing and assortment in Saccharum spontaneum L., the most widely distributed, and morphologically and cytologically variable of the species of Saccharum. This conclusion was based on the analysis of a segregating population from across between S. spontaneum 'SES 208' and a spontaneously-doubled haploid of itself, derived from anther culture. To determine whether polysomic inheritance is common in Saccharum and whether it is observed in a typical biparental cross, we studied chromosome pairing and assortment in 44 progeny of a cross between euploid, meiotically regular, 2n=80 forms of Saccharum officinarum 'LA Purple' and Saccharum robustum ' Mol 5829'. Papuan 2n=80 forms of S. robustum have been suggested as the immediate progenitor species for cultivated sugarcane (S. officinarum). A total of 738 loci in LA Purple and 720 loci in Mol 5829 were amplified and typed in the progeny by arbitrarily primed PCR using 45 primers. Fifty and 33 single-dose polymorphisms were identified in the S. officinarum and S. robustum genomes, respectively (χ 2 at 98%). Linkage analysis of single-dose polymorphisms in both genomes revealed linkages in repulsion and coupling phases. In the S. officinarum genome, a map hypothesis gave 7 linkage groups with 17 linked and 33 unlinked markers. Four of 13 pairwise linkages were in repulsion phase and 9 were in coupling phase. In the S. robustum genome, a map hypothesis gave 5 linkage groups, defined by 12 markers, with 21 markers unlinked, and 2 of 9 pairwise linkages were in repulsion phase. Therefore, complete polysomic inheritance was not observed in either species, suggesting that chromosomal behavior is different from that observed by linkage analysis of over 500 markers in the S. spontaneum map. Implications of this finding for evolution and breeding are discussed.

  12. Immunity of multiplex networks via acquaintance vaccination

    Science.gov (United States)

    Wang, Zhen; Zhao, Da-Wei; Wang, Lin; Sun, Gui-Quan; Jin, Zhen

    2015-11-01

    How to find the effective approach of immunizing a population is one open question in the research of complex systems. Up to now, there have been a great number of works focusing on the efficiency of various immunization strategies. However, the majority of these existing achievements are limited to isolated networks, how immunization affects disease spreading in multiplex networks seems to need further exploration. In this letter, we explore the impact of the acquaintance immunization in multiplex networks, where two kinds of immunization strategies, multiplex node-based acquaintance immunization and layer node-based acquaintance immunization, are proposed. With the generating function method, our theoretical framework is able to accurately calculate the critical immunization threshold which is one of the most important indexes to predict the epidemic regime. Moreover, we further uncover that, with the increment of degree correlation between network layers, the immunization threshold declines for multiplex node-based acquaintance immunization, but slowly increases for layer node-based acquaintance immunization.

  13. Product Assortment in a Triopoly

    OpenAIRE

    Steven M. Shugan

    1989-01-01

    Producers of super-premium ice cream, such as Häagen-Dazs, offer a smaller assortment of flavors than the producers of lesser quality ice cream. Examples of this phenomenon can be found in other industries as well. In many industries, the producers of higher-quality products offer a smaller assortment of flavors, colors, sizes, patterns, textures, fragrances, tones, styles, models, designs, types or other options. This paper explores when and why producers of super-premium products should fin...

  14. Acquaintance Rape on College and University Campuses

    Science.gov (United States)

    Romeo, Felicia F.

    2004-01-01

    While a university experience offers young women many rewards, unfortunately, there are also significant dangers, and one of these dangers is men who are sexual predators. Acquaintance rape is a sexual assault perpetrated by someone who is known to the victim. It is a violent and serious crime that is far too common an occurrence at our…

  15. Attitudes toward Acquaintance Rape and Risk Appraisal.

    Science.gov (United States)

    Wright, Doris J.

    1999-01-01

    Examines how men and women judge the presence of risk factors in a scripted acquaintance rape scenario and if alcohol was a significant factor in assessing risk. Significant differences were found in African American and Caucasian participants' attitudes toward rape and risk appraisal. There was a negative correlation between risk appraisal and…

  16. Acquaintance Rape and the College Social Scene.

    Science.gov (United States)

    Ward, Sally K.; And Others

    1991-01-01

    Estimated incidence of unwanted sexual experiences on one college campus. Based on self-administered survey, estimated that 34 percent of women had experienced contact; 20 percent experienced attempted intercourse; and 10 percent experienced completed intercourse. Argues that stranger-acquaintance dichotomy be abandoned in favor of typology…

  17. Acquaintance Rape: A Case Study Approach.

    Science.gov (United States)

    Marinelli, Rosalie D.

    1994-01-01

    Describes a case study approach to acquaintance rape used in a Personal Health and Lifestyles course at the University of Nevada in Reno that allows students to discuss the characters in a scenario, an instructional process seen as less threatening than describing personal experiences. (MDM)

  18. Japanese International Students' Attitudes toward Acquaintance Rape.

    Science.gov (United States)

    Motoike, Janice; Stockdale, Margaret

    This study looked at the influence of an Asian sociocultural variable, loss of face or social integrity, as a predictor of perceptions of acquaintance rape among Japanese students. In addition to the expected associations between gender, sexism, and perceptions of rape, loss of face was predicted to interact with the perpetrator's reference group…

  19. Acquaintance Rape on Campus: A Model for Institutional Response.

    Science.gov (United States)

    Burling, Philip

    This booklet explains the actions that college or university administrators should take to prevent or respond to incidents of acquaintance rape ("date rape") on campus. It outlines specific preventive measures, risk management procedures, and internal disciplinary procedures for acquaintance rape cases. Institutions should define acquaintance rape…

  20. More choice is better : Effects of assortment size and composition on assortment evaluations

    NARCIS (Netherlands)

    Koelemeijer, K.; Oppewal, H.

    2005-01-01

    This study focuses on effects of assortment size and composition on assortment evaluation. Data from a choice experiment conducted with members of a large consumer panel suggest that adding any item improves assortment evaluation, regardless of their attributes or the size of the assortment. Althoug

  1. Assortment Variety : Attribute versus Product-Based

    NARCIS (Netherlands)

    van Herpen, H.W.I.; Pieters, R.

    2000-01-01

    Retailers need to decide on the content and structure of their product assortments, and thereby on the degree of variety that they offer to their customers.This paper compares measures of assortment variety and relates them to underlying variety components.We conceptualize assortment variety from a

  2. Consensus in personality judgments at zero acquaintance.

    Science.gov (United States)

    Albright, L; Kenny, D A; Malloy, T E

    1988-09-01

    This research focused on the target effect on a perceiver's judgments of personality when the perceiver and the target are unacquainted. The perceiver was given no opportunity to interact with the target, a condition we refer to as zero acquaintance. We reasoned that in order to make personality judgments, perceivers would use the information available to them (physical appearance). Consensus in personality judgments would result, then, from shared stereotypes about particular physical appearance characteristics. Results from three separate studies with 259 subjects supported this hypothesis. On two of the five dimensions (extraversion and conscientiousness) on which subjects rated each other, a significant proportion of variance was due to the stimulus target. Consensus on judgments of extraversion appears to have been largely mediated by judgments of physical attractiveness. Across the three studies there was also evidence that the consensus in judgments on these two dimensions had some validity, in that they correlated with self-judgments on those two dimensions. PMID:3171912

  3. Date and Acquaintance Rape: Perceptions and Attitude Change Strategies.

    Science.gov (United States)

    Harrison, Patrick J.; And Others

    1991-01-01

    Investigated the dimensions of university students' (n=96) attitudes toward date and acquaintance rape. Examined the effects of a program designed to change those attitudes. Found college men had substantially greater tendencies to blame the victim for date and acquaintance rape than did women. (Author/ABL)

  4. Product assortment and individual decision processes.

    Science.gov (United States)

    Chernev, Alexander

    2003-07-01

    Research presented in this article examines the impact of product assortment on individuals' decisions. Four experiments report converging evidence that the impact of assortment is moderated by the degree to which individuals have articulated attribute preferences, whereby individuals with an articulated ideal point are more likely to prefer larger assortments than individuals without articulated preferences. The data further show that choices made from large assortments are associated with more selective, alternative-based, and confirmatory processing for individuals with articulated preferences and more comprehensive, attribute-based, and comparative processing for those without articulated preferences.

  5. Understanding Consumer Reactions to Assortment Unavailability

    NARCIS (Netherlands)

    L.M. Sloot (Laurens)

    2006-01-01

    textabstractAny regular grocery shopper will be familiar with the annoying situation in which his or her preferred product is not available at the moment (s) he wants to buy it. Assortment unavailability can be temporary (e.g., out-of-stock) or permanent in nature (e.g., assortment reduction). Shop

  6. Perceptions and evaluations of assortment variety

    NARCIS (Netherlands)

    van Herpen, H.W.I.

    2001-01-01

    Given the explosive growth in the number of products, managing their assortments is a challenging task for retailers. An understanding of consumer responses to changes in assortment size and composition is required. This dissertation examines consumers' perceptions and evaluations of product assortm

  7. An Ideal Assortative Network and Synchronization

    Institute of Scientific and Technical Information of China (English)

    DONG Cheng-Dong; LIU Zeng-Rong

    2007-01-01

    This paper proposes a novel complex network with assortative property based on multi-center networks. The average path length and clustering coefficient of the network are calculated, and the impact on the network topology is investigated. A simple dynamic system established on the proposed network is used to analyze how the assortative property of the network affects synchronization.

  8. The factors affecting sexual assaults committed by strangers and acquaintances.

    Science.gov (United States)

    Pazzani, Lynn M

    2007-07-01

    Research on the causes of sexual assault typically analyzes rape committed by acquaintances and strangers together, despite the fact that the characteristics of the assault in these two circumstances are very different. Thus, this work examines whether the causes of each type of sexual assault--stranger and acquaintance rape--differ. The results of the analyses reveal that variables that describe a culture of gender equality, prior child abuse, and prior sexual assaults are associated with acquaintance assaults. In contrast, a culture of "hypermasculinity" is associated with stranger rape. The implications of these findings are discussed. PMID:17600307

  9. Geo-Social Group Queries with Minimum Acquaintance Constraint

    OpenAIRE

    Zhu, Qijun; Hu, Haibo; Xu, Jianliang; Lee, Wang-Chien

    2014-01-01

    The prosperity of location-based social networking services enables geo-social group queries for group-based activity planning and marketing. This paper proposes a new family of geo-social group queries with minimum acquaintance constraint (GSGQs), which are more appealing than existing geo-social group queries in terms of producing a cohesive group that guarantees the worst-case acquaintance level. GSGQs, also specified with various spatial constraints, are more complex than conventional spa...

  10. Assortment of encounters and evolution of cooperativeness.

    Science.gov (United States)

    Eshel, I; Cavalli-Sforza, L L

    1982-02-01

    The method of evolutionary stable strategies (ESS), in its current form, is confronted with a difficulty when it tries to explain how some social behaviors initiate their evolution. We show that this difficulty may be removed by changing the assumption made tacitly in game theory (and in ESS) of randomness of meetings or encounters. In reality, such randomness seems to be rare in nature. Family, population and social structure, customs, and habits impose various types of deviation from randomness. Introducing nonrandomness of meeting in a way formally similar to assortative mating, we show that the bar to initial increase of inherited cooperative or altruistic behaviors can be removed, provided there is sufficient assortment of meetings. Family structure may cause contacts predominantly between certain types of relatives, and one can reconstruct some results of classical kin selection in terms of evolutionary stable strategy with assortative meetings. Neighbor effects and group selection might be similarly treated. Assortment need not be a passive consequence of population and social structure, but it can also be actively pursued. Behaviors favoring the choice of cooperative companions will have the effect of favoring the evolution of cooperativeness. It can be shown that discrimination in the choice of companions, especially if combined with assortment, can favor the development of cooperativeness, making initial increase of cooperative behavior possible even at levels of assortment passively imposed which would not be adequate, per se, to guarantee the increase of cooperativeness. It is possible that, in some cases, cooperativeness and behavior favoring some type of assortment are coselected.

  11. The Personal Acquaintance Measure: a tool for appraising one's acquaintance with any person.

    Science.gov (United States)

    Starzyk, Katherine B; Holden, Ronald R; Fabrigar, Leandre R; Macdonald, Tara K

    2006-05-01

    The authors developed and evaluated the psychometric properties of the 18-item Personal Acquaintance Measure (PAM) and investigated how the PAM relates to self- other agreement in personality ratings. Results support that 6 factors represent the PAM (Duration, Frequency of Interaction, Knowledge of Goals, Physical Intimacy, Self-Disclosure, Social Network Familiarity), which showed evidence of internal consistency, test-retest reliability over 3 weeks, sensitivity to known group differences, discriminant validity from socially desirable responding, and convergent validity with other relationship inventories. Results also show that the PAM positively predicted self-other agreement. The authors discuss the implications of these findings for the PAM and research in person perception, although this measure may also be used in other research areas. PMID:16737376

  12. Marital assortment and phenotypic convergence: longitudinal evidence.

    Science.gov (United States)

    Caspi, A; Herbener, E S

    1993-01-01

    This study provides a direct test of whether the observed similarity of spouses is due to initial assortment rather than to convergence of phenotypes. With data from three well-known longitudinal studies, phenotypic convergence is examined using both variable- and person-centered analyses. The longitudinal evidence does not support the hypothesis that couples increasingly resemble each other with time. Spouse correlations most likely reflect initial assortment at marriage and not the convergence of phenotypes.

  13. Rate of phenotypic assortment in Tetrahymena thermophila.

    Science.gov (United States)

    Doerder, F P; Deak, J C; Lief, J H

    1992-01-01

    During vegetative, asexual reproduction in heterozygous Tetrahymena thermophila, the macronucleus divides amitotically to produce clonal lineages that express either one or the other allele but not both. Because such phenotypic assortment has been described for every locus studied, its mechanism has important implications concerning the development and structure of the macronucleus. The primary tools to study assortment are Rf, the rate at which subclones come to express a single allele stably, and the output ratio, the ratio of assortee classes. Because Rf is related to the number of assorting units, a constant Rf for all loci suggests that all genes are maintained at the same copy number. Output ratios reflect the input ratio of assorting units, with a 1:1 output ratio implying equal numbers of alleles at the end of macronuclear development. Because different outcomes would suggest a different macronuclear structure, it is crucial that these parameters be accurately measured. Although published Rf values are similar for all loci measured, there has been no commonly accepted form of presentation and analysis. Here we examine the experimental determination of Rf. First, we use computer simulation to describe how the variability inherent in the assortment process affects experimental determination of Rf. Second, we describe a simple method of plotting assortment data that permits the uniform calculation of Rf, and we describe how to measure Rf accurately in instances when it is possible to score only the recessive allele. Using this method to produce truly comparable Rfs for all published data, we find that most, if not all, loci assort at Rfs consistent with approximately 45 assorting units, as has been asserted.

  14. Higher order assortativity in complex networks

    CERN Document Server

    Arcagni, Alberto; Stefani, Silvana; Torriero, Anna

    2016-01-01

    Assortativity was first introduced by Newman and has been extensively studied and applied to many real world networked systems since then. Assortativity is a graph metrics and describes the tendency of high degree nodes to be directly connected to high degree nodes and low degree nodes to low degree nodes. It can be interpreted as a first order measure of the connection between nodes, i.e. the first autocorrelation of the degree-degree vector. Even though assortativity has been used so extensively, to the author's knowledge, no attempt has been made to extend it theoretically. This is the scope of our paper. We will introduce higher order assortativity by extending the Newman index based on a suitable choice of the matrix driving the connections. Higher order assortativity will be defined for paths, shortest paths, random walks of a given time length, connecting any couple of nodes. The Newman assortativity is achieved for each of these measures when the matrix is the adjacency matrix, or, in other words, the...

  15. An improved acquaintance immunization strategy for complex network.

    Science.gov (United States)

    Chen, Li; Wang, Dongyi

    2015-11-21

    The acquaintance immunization strategy is a common strategy to suppress epidemic on complex network which achieves a seemingly perfect balance between cost and effectiveness compared with other canonical immunization strategies. However, the acquaintance immunization strategy fails to take the time-varying factor and local information of nodes into consideration, which limits its effectiveness in some specific network topology. Our improved immunization strategy is based on a new mathematical model Network Structure Index (NSI), which digs deep to measure the connection property and surrounding influence of a node's neighbor nodes to better determine the importance of nodes during immunization. Both mathematical derivation and the simulation program tested on various network topology support our idea that this improved acquaintance immunization strategy protects more nodes from infection and immunizes important nodes more efficiently than the original strategies. As to say, our strategy has more adaptability and achieves a more reasonable balanced point between cost and effectiveness.

  16. Simple models of assortment through environmental feedback.

    Science.gov (United States)

    Pepper, John W

    2007-01-01

    Social evolution depends critically on assortment, or segregation versus even mixing, between cooperators and noncooperators. Altruistic traits, which reduce the absolute fitness of their bearers, cannot evolve without positive assortment (excess segregation). The question of how positive assortment can arise has been controversial, but most evolutionary biologists believe that common descent is the only effective general mechanism. Here I investigate another recently proposed mechanism for generating nonrandom assortment, termed environmental feedback. This requires only that two forms of a trait affect the quality of the local environment differently in such a way that all individuals are more likely to leave low-quality locales. Experiments with simple computational models confirm that environmental feedback generates significant levels of genetic similarity among non-kin within locales. The mechanism is fairly general, and can under some conditions produce levels of genetic similarity comparable to those resulting from close genealogical relationship. Environmental feedback can also generate the negative assortment necessary for the evolution of spiteful traits. Environmental feedback is expected to create positive frequency-dependent selection, which thus favor any social trait that becomes common in the population. Results from this stylized model suggest that environmental feedback could be important in the evolution of both cooperation and spite, within as well as between species.

  17. Young Children's Collaboration on the Computer with Friends and Acquaintances

    Science.gov (United States)

    Chen, Yi-Jeng

    2016-01-01

    The processes and patterns of strategies used by children when drawing on the computer with friends and acquaintances were investigated in a case study. The participants were five-and-six-year-old children and the study took place in their home settings. The data collection methods consisted of interviews, observations, audio recordings, video…

  18. Gender Norms and Retaliatory Violence against Spouses and Acquaintances

    Science.gov (United States)

    Feld, Scott L.; Felson, Richard B.

    2008-01-01

    This article examines an experiment embedded within a nationally representative survey of adult Americans to investigate gender norms regarding retaliatory violence between spouses and acquaintances. Contrary to claims that societal norms permit violence within marriage, respondents disapproved of retaliatory violence against spouses more than…

  19. Hidden, Unacknowledged, Acquaintance, and Date Rape: Looking Back, Looking Forward

    Science.gov (United States)

    Koss, Mary P.

    2011-01-01

    In this commentary, the author reflects on two articles that have been among the most highly cited publications in "Psychology of Women Quarterly" ("PWQ") over its first 35 years, "The Hidden Rape Victim: Personality, Attitudinal, and Situational Characteristics" (Koss, 1985) and "Stranger and Acquaintance Rape: Are There Differences in the…

  20. A Model Acquaintance Rape Prevention Program for Men.

    Science.gov (United States)

    Berkowitz, Alan D.

    1994-01-01

    Describes the underlying philosophy, content and evaluation issues, and selection and training of facilitators for a model acquaintance rape prevention program for male students conducted at Hobart College. Provides guidelines to help other colleges and universities implement a model rape prevention program for men that uses small-group discussion…

  1. Date and Acquaintance Rape among a Sample of College Students.

    Science.gov (United States)

    Mills, Crystal S.; Granoff, Barbara J.

    1992-01-01

    Conducted date and acquaintance rape needs-assessment survey on 106 male and 113 female college students. Thirty-two women acknowledged that they were victims of rape or attempted rape, and majority reported multiple victimizations. Eighteen men admitted to committing acts that met legal definition of sexual assault in Hawaii. (Author/NB)

  2. Acquaintance Rape on College Campuses: A Review of the Literature.

    Science.gov (United States)

    Kier, Frederick J.

    Although research on acquaintance, or date rape, dates back to the late 1950's, only recently has the literature in this area focused on prevention. In addition, although research has shown that, conservatively, 1 out of 10 women on university campuses has been raped by someone with whom she is familiar, little appears to have been done about the…

  3. Acquaintance Rape on Campus: The Problem, the Victims, and Prevention.

    Science.gov (United States)

    Neff, Laurie

    1988-01-01

    Asserts that, although providing educational programs and materials on acquaintance rape and prevention strategies is important, attention must also be given to victims. Discusses recognition of stress response pattern of victims suffering from Rape Trauma Syndrome and provision of appropriate referral and support services. Includes selected list…

  4. Multivariate models of mixed assortment: phenotypic assortment and social homogamy for education and fluid ability.

    Science.gov (United States)

    Reynolds, C A; Baker, L A; Pedersen, N L

    2000-11-01

    Phenotypic assortment is assumed to be the principal mechanism of spouse similarity in most biometrical studies. Other assortment mechanisms, such as social homogamy, may be plausible. Two models are presented that consider phenotypic assortment and social homogamy simultaneously (i.e., mixed assortment), where selective associations between social background factors (Model I) versus selective associations between total environments (Model II) distinguish the models. A series of illustrative analyses was undertaken for education and fluid ability available on a sample of 116 Swedish twin pairs and their spouses. On the basis of several fit criteria Model I was preferred over Model II. Both social homogamy and phenotypic assortment may contribute to spouse similarity for educational attainment and fluid ability. Furthermore, spouse similarity for fluid ability may arise indirectly from social homogamy and phenotypic assortment for educational attainment. Power analyses indicated greater observed power for Model I than Model II. Additional power analyses indicated that considerably more twin-spouse sets would be needed for Model II than Model I, to resolve social homogamy and phenotypic assortment. Effects of misspecification of mechanisms of spouse similarity are also briefly discussed.

  5. Assortativity in generalized preferential attachment models

    CERN Document Server

    Krot, Alexander

    2016-01-01

    In this paper, we analyze assortativity of preferential attachment models. We deal with a wide class of preferential attachment models (PA-class). It was previously shown that the degree distribution in all models of the PA-class follows a power law. Also, the global and the average local clustering coefficients were analyzed. We expand these results by analyzing the assortativity property of the PA-class of models. Namely, we analyze the behavior of $d_{nn}(d)$ which is the average degree of a neighbor of a vertex of degree $d$.

  6. Assortative mating by unwed biological parents of adopted children.

    Science.gov (United States)

    Plomin, R; DeFries, J C; Roberts, M K

    1977-04-22

    Analyses of data obtained from 662 unwed couples whose children were relinquished for adoption reveal that biological parents of adopted children mate assortatively. For physical characters, assortative mating of unwed parents was similar to that of wed parents; for behavior characters, however, there was less assortative mating by the unwed parents. Because assortative mating inflates estimates of genetic parameters in adoption studies, future studies should collect information on both biological parents.

  7. Anticipated identification costs: Improving assortment evaluation by diagnostic attributes

    NARCIS (Netherlands)

    Herpen, van E.; Pieters, F.G.M.

    2007-01-01

    Abstract Consumers often make quick assessments of product assortments, to determine if these are worthwhile for further investigation. They anticipate how difficult it will be to distinguish the various options in the assortment, which will influence their assortment evaluations. We reason that the

  8. Stranger and Acquaintance Rape: Are There Differences in the Victim's Experience?

    Science.gov (United States)

    Koss, Mary P.; And Others

    1988-01-01

    Examined rape by strangers and by acquaintances, including nonromantic acquaintances, casual dates, steady dates, and family members in 489 rape victims. Acquaintance rape typically involved single offender and multiple episodes, was less often perceived as rape or revealed to anyone, and, except for rapes by family members, was rated less…

  9. Assortment and the evolution of generalized reciprocity.

    Science.gov (United States)

    Rankin, Daniel J; Taborsky, Michael

    2009-07-01

    Reciprocity is often invoked to explain cooperation. Reciprocity is cognitively demanding, and both direct and indirect reciprocity require that individuals store information about the propensity of their partners to cooperate. By contrast, generalized reciprocity, wherein individuals help on the condition that they received help previously, only relies on whether an individual received help in a previous encounter. Such anonymous information makes generalized reciprocity hard to evolve in a well-mixed population, as the strategy will lose out to pure defectors. Here we analyze a model for the evolution of generalized reciprocity, incorporating assortment of encounters, to investigate the conditions under which it will evolve. We show that, in a well-mixed population, generalized reciprocity cannot evolve. However, incorporating assortment of encounters can favor the evolution of generalized reciprocity in which indiscriminate cooperation and defection are both unstable. We show that generalized reciprocity can evolve under both the prisoner's dilemma and the snowdrift game.

  10. Assortativity Decreases the Robustness of Interdependent Networks

    CERN Document Server

    Zhou, Di; Scala, Antonio; Stanley, H Eugene

    2012-01-01

    The protection of critical infrastructures is one of the highest priorities in our technological society. It was recently recognized that interdependencies among different networks can play a crucial role in triggering cascading failures and hence system-wide disasters. A recent model shows how pairs of interdependent networks can exhibit an abrupt percolation transition as failures accumulate. We report on the effects of topology on failure propagation for a model system consisting of two interdependent networks. We find that the internal node correlations in each of the two interdependent networks significantly changes the critical density of failures that triggers the total disruption of the two-network system. We find, in particular, that the assortativity within a single network decreases the robustness of the entire system. The results of this study on the influence of assortativity may provide insights into ways of improving the robustness of network architecture, and thus enhance the level of protecti...

  11. Phenotypic assortment in Tetrahymena thermophila: assortment kinetics of antibiotic-resistance markers, tsA, death, and the highly amplified rDNA locus.

    Science.gov (United States)

    Merriam, E V; Bruns, P J

    1988-10-01

    Phenotypic assortment in Tetrahymena thermophila results from random distribution of alleles during amitotic division of the macronucleus. The rate of assortment is dependent on input ratio and the number of assorting units. The assortment of the antibiotic resistance markers Chx, Mpr and gal was determined and is consistent for each with the model of 45 assorting chromosomes. The gene tsA (previously ts-1) shows normal assortment, in contrast to previous reports. A mutation in the highly amplified ribosomal locus (rdnA2) assorts as if present at only 45 copies. Death of clones occurred at a rate consistent with assortment for a single gene.

  12. Emergence of clustering in an acquaintance model without homophily

    International Nuclear Information System (INIS)

    We introduce an agent-based acquaintance model in which social links are created by processes in which there is no explicit homophily. In spite of the homogeneous nature of the social interactions, highly-clustered social networks can arise. The crucial feature of our model is that of variable transitive interactions. Namely, when an agent introduces two unconnected friends, the rate at which a connection actually occurs between them depends on the number of their mutual acquaintances. As this transitive interaction rate is varied, the social network undergoes a dramatic clustering transition. Close to the transition, the network consists of a collection of well-defined communities. As a function of time, the network can also undergo an incomplete gelation transition, in which the gel, or giant cluster, does not constitute the entire network, even at infinite time. Some of the clustering properties of our model also arise, but in a more gradual manner, in Facebook networks. Finally, we discuss a more realistic variant of our original model in which network realizations can be constructed that quantitatively match Facebook networks. (paper)

  13. Assortative mating for relative weight: genetic implications.

    Science.gov (United States)

    Allison, D B; Neale, M C; Kezis, M I; Alfonso, V C; Heshka, S; Heymsfield, S B

    1996-03-01

    Most work on the genetics of relative weight has not considered the role of assortative mating, i.e., mate selection based on similarity between mates. We investigated the extent to which engaged men and women in an archival longitudinal database were similar to each other in relative body weight prior to marriage and cohabitation. After controlling for age, a small but statistically significant mate correlation was found for relative weight (r=.13, p=.023), indicating some assortative mating. Furthermore, we examined whether mate similarity in relative weight prior to marriage predicts survival of the marriage. No significant effects were found. In sum, these results are consistent with those of other studies in suggesting that there is a small but significant intermate correlation for relative weight. However, they are unique in showing that these results cannot be explained on the basis of (a) cohabitation, (b) age similarity, or (c) selective survival of marriages between couples more similar in relative weight. The implications of these findings for heritability studies, linkage studies, and the estimation of shared environmental effects are discussed. PMID:8639146

  14. ASSORTMENT AND PRICE POLICY OF STATE PHARMACIES OF MOSCOW

    Directory of Open Access Journals (Sweden)

    I. V. Voronovich

    2015-01-01

    Full Text Available The most important index which determines the level and quality of pharmaceutical support is the correspondence of assortment to consumers needs. Assortment policy is determined by the functions implemented, and the problems of organization of pharmaceutical support of medicinal organizations within the frameworks of substantiated and reasonable expenditure of budget funds, and affordable pharmaceutical support of the population. The purpose of this research was the study of assortment and price policy of state pharmacies of Moscow. The objects were pharmacy subdivisions of state pharmacy network of Moscow. We have used sociological methods (questionnaire, interviewing, method of marketing, and statistic analysis. We have studied the assortment structure, assortment groups’ distribution on price segments. We have established that the drugs, more than 60% of which are foreign-made occupied more than a half of the assortment. Medicinal drugs in 50 rubles price spectrum occupy the biggest share of pharmacy assortment. Distribution within every assortment group revealed that more than a half of drugs are in average price spectrum from 50 to 500 rubles. Average charge for VED amounts to 21.87%, and for drugs which were not included in VED list – 34.07%. The charge for the goods, the price of which is not regulated, trade charge is more. 

  15. Change in BMI accurately predicted by social exposure to acquaintances.

    Directory of Open Access Journals (Sweden)

    Rahman O Oloritun

    Full Text Available Research has mostly focused on obesity and not on processes of BMI change more generally, although these may be key factors that lead to obesity. Studies have suggested that obesity is affected by social ties. However these studies used survey based data collection techniques that may be biased toward select only close friends and relatives. In this study, mobile phone sensing techniques were used to routinely capture social interaction data in an undergraduate dorm. By automating the capture of social interaction data, the limitations of self-reported social exposure data are avoided. This study attempts to understand and develop a model that best describes the change in BMI using social interaction data. We evaluated a cohort of 42 college students in a co-located university dorm, automatically captured via mobile phones and survey based health-related information. We determined the most predictive variables for change in BMI using the least absolute shrinkage and selection operator (LASSO method. The selected variables, with gender, healthy diet category, and ability to manage stress, were used to build multiple linear regression models that estimate the effect of exposure and individual factors on change in BMI. We identified the best model using Akaike Information Criterion (AIC and R(2. This study found a model that explains 68% (p<0.0001 of the variation in change in BMI. The model combined social interaction data, especially from acquaintances, and personal health-related information to explain change in BMI. This is the first study taking into account both interactions with different levels of social interaction and personal health-related information. Social interactions with acquaintances accounted for more than half the variation in change in BMI. This suggests the importance of not only individual health information but also the significance of social interactions with people we are exposed to, even people we may not consider as

  16. Assortment structure in beech coppice stands in Boljevac region

    Directory of Open Access Journals (Sweden)

    Danilović Milorad

    2004-01-01

    Full Text Available Assortment structure in beech coppice stands was studied in the area of Boljevac. Assortment structure was evaluated according to the articles of the valid standard (JUS. The assortments represented in the assortment structure, based on the stemwood quality are: Logs for matches, sawlogs I II and III classes, mine timber, technical roundwood, pulpwood, wood for excelsior and fuelwood, I and II classes. The results of the analyses show that the value assortment structure (sum of the values of assortments produced from one tree grows significantly with the increase of tree diameter and this dependence is presented by a degree function. The value percentage of logs for matches, sawlogs of the I and II classes, technical roundwood, mine timber, fuelwood and pulpwood, grows with the increase of the tree diameter. The occurrence of better quality logs (sawlogs in these stands, in contrast to the beech coppice stand in the area of Crni Vrh results from the more favourable diameter structure. There are no statistically significant differences between the value assortment structure on the established sample plot series within the same locality, consequently the data ere united. Because of the differences in stand age, the data are not unified for the localities, although there are no statistically significant differences between value assortment structure for diameter degrees represented in them. False heart (red heart is one of very significant defects of beech wood, and its incidence, inter alia, depends on tree age. The low effect of this defect of wood resulted in a significant percentage of logs for matches. Along with the value assortment structure this paper also presents the percentage of assortments depending on tree diameter.

  17. A Review of Acquaintance/Date Rape Research: Implications for the University Campus.

    Science.gov (United States)

    Drapeau, Robert F.

    1992-01-01

    Reviews literature on incidence and ramifications of acquaintance rape and discusses specific gender-related factors. Identifies four areas that require proactive college response: access and intrusion, nonnegligent hiring and training, alcohol and drugs, and awareness education. Concludes that effective response to acquaintance rape requires…

  18. Preventing Alcohol-Related Problems on Campus: Acquaintance Rape. A Guide for Program Coordinators.

    Science.gov (United States)

    Finn, Peter

    This is a guide for college and university program coordinators and planning committees on how to establish, expand, or improve a program on the prevention of acquaintance rape. Information is given for Presidents, Vice Presidents, and Deans on the relationship between acquaintance rape and alcohol, reasons for top administrators to become…

  19. College Women's Fears and Precautionary Behaviors Relating to Acquaintance Rape and Stranger Rape.

    Science.gov (United States)

    Hickman, Susan E.; Muehlenhard, Charlene L.

    1997-01-01

    Studied the fears, beliefs, and behaviors of 139 college women about acquaintance and stranger rape. Women were more afraid of stranger rape and took more precautions against it but paradoxically believed that acquaintance rape was more common. Precautionary behaviors were best predicted by level of fear. Theoretical and educational implications…

  20. Where Do I Start?: A Parents' Guide for Talking to Teens about Acquaintance Rape.

    Science.gov (United States)

    Bateman, Py; Stringer, Gayle M.

    This is a booklet designed for parents interested in helping their teenage children avoid the possibility of sexual assault. The first section of the booklet provides background on acquaintance rape, discussing attitudes about acquaintance rape, what boys and girls learn about sexual activity, gender different perceptions, and teenagers and peer…

  1. A Comparison of Strategies for Changing College Students' Attitudes toward Acquaintance Rape.

    Science.gov (United States)

    Nelson, Eileen S.; Torgler, Cyndee C.

    1990-01-01

    Compared effects of strategies for informing college students about date rape. Assigned students to either experimental group that viewed videotape on acquaintance rape (n=33), experimental group that read brochure on acquaintance rape (n=31), or control group (n=25). Findings revealed no significant difference between effects of videotape and…

  2. Evolution of assortative mating in a population expressing dominance.

    Directory of Open Access Journals (Sweden)

    Kristan A Schneider

    Full Text Available In this article, we study the influence of dominance on the evolution of assortative mating. We perform a population-genetic analysis of a two-locus two-allele model. We consider a quantitative trait that is under a mixture of frequency-independent stabilizing selection and density- and frequency-dependent selection caused by intraspecific competition for a continuum of resources. The trait is determined by a single (ecological locus and expresses intermediate dominance. The second (modifier locus determines the degree of assortative mating, which is expressed in females only. Assortative mating is based on similarities in the quantitative trait ('magic trait' model. Analytical conditions for the invasion of assortment modifiers are derived in the limit of weak selection and weak assortment. For the full model, extensive numerical iterations are performed to study the global dynamics. This allows us to gain a better understanding of the interaction of the different selective forces. Remarkably, depending on the size of modifier effects, dominance can have different effects on the evolution of assortment. We show that dominance hinders the evolution of assortment if modifier effects are small, but promotes it if modifier effects are large. These findings differ from those in previous work based on adaptive dynamics.

  3. Assortative mating for cultural identification as indicated by language use.

    Science.gov (United States)

    Nagoshi, C T; Johnson, R C; Danko, G P

    1990-01-01

    Persons of Japanese ancestry from Hawaii who marry within their own racial/ethnic group show a significant degree of homogamous assortative mating for "pidgin" and for standard English usage, variables reflective of important cultural differences in Hawaii. Persons of Japanese ancestry who married persons of other racial/ethnic groups had less exposure to pidgin in their parental homes and were less likely to speak this dialect of English. Sibling-spouse analyses suggested that assortment for such language use is entirely due to social homogamy rather than active phenotypic assortment.

  4. Interdisciplinary Matchmaking: Choosing Collaborators by Skill, Acquaintance and Trust

    Science.gov (United States)

    Hupa, Albert; Rzadca, Krzysztof; Wierzbicki, Adam; Datta, Anwitaman

    Social networks are commonly used to enhance recommender systems. Most of such systems recommend a single resource or a person. However, complex problems or projects usually require a team of experts that must work together on a solution. Team recommendation is much more challenging, mostly because of the complex interpersonal relations between members. This chapter presents fundamental concepts on how to score a team based on members' social context and their suitability for a particular project. We represent the social context of an individual as a three-dimensional social network (3DSN) composed of a knowledge dimension expressing skills, a trust dimension and an acquaintance dimension. Dimensions of a 3DSN are used to mathematically formalize the criteria for prediction of the team's performance. We use these criteria to formulate the team recommendation problem as a multi-criteria optimization problem. We demonstrate our approach on empirical data crawled from two web2.0 sites: onephoto.net and a social networking site. We construct 3DSNs and analyze properties of team's performance criteria.

  5. Assortative mixing in functional brain networks during epileptic seizures

    CERN Document Server

    Bialonski, Stephan

    2013-01-01

    We investigate assortativity of functional brain networks before, during, and after one-hundred epileptic seizures with different anatomical onset locations. We construct binary functional networks from multi-channel electroencephalographic data recorded from 60 epilepsy patients, and from time-resolved estimates of the assortativity coefficient we conclude that positive degree-degree correlations are inherent to seizure dynamics. While seizures evolve, an increasing assortativity indicates a segregation of the underlying functional network into groups of brain regions that are only sparsely interconnected, if at all. Interestingly, assortativity decreases already prior to seizure end. Together with previous observations of characteristic temporal evolutions of global statistical properties and synchronizability of epileptic brain networks, our findings may help to gain deeper insights into the complicated dynamics underlying generation, propagation, and termination of seizures.

  6. Lower bound of assortativity coefficient in scale-free networks

    CERN Document Server

    Yang, Dan; Zhou, Tao

    2016-01-01

    The degree-degree correlation is important in understanding the structural organization of a network and the dynamics upon a network. Such correlation is usually measured by the assortativity coefficient $r$, with natural bounds $r \\in [-1,1]$. For scale-free networks with power-law degree distribution $p(k) \\sim k^{-\\gamma}$, we analytically obtain the lower bound of assortativity coefficient in the limit of large network size, which is not -1 but dependent on the power-law exponent $\\gamma$. This work challenges the validation of assortativity coefficient in heterogeneous networks, suggesting that one cannot judge whether a network is positively or negatively correlated just by looking at its assortativity coefficient.

  7. Continuous microfluidic assortment of interactive ligands (CMAIL)

    Science.gov (United States)

    Hsiao, Yi-Hsing; Huang, Chao-Yang; Hu, Chih-Yung; Wu, Yen-Yu; Wu, Chung-Hsiun; Hsu, Chia-Hsien; Chen, Chihchen

    2016-08-01

    Finding an interactive ligand-receptor pair is crucial to many applications, including the development of monoclonal antibodies. Biopanning, a commonly used technique for affinity screening, involves a series of washing steps and is lengthy and tedious. Here we present an approach termed continuous microfluidic assortment of interactive ligands, or CMAIL, for the screening and sorting of antigen-binding single-chain variable antibody fragments (scFv) displayed on bacteriophages (phages). Phages carrying native negative charges on their coat proteins were electrophoresed through a hydrogel matrix functionalized with target antigens under two alternating orthogonal electric fields. During the weak horizontal electric field phase, phages were differentially swept laterally depending on their affinity for the antigen, and all phages were electrophoresed down to be collected during the strong vertical electric field phase. Phages of different affinity were spatially separated, allowing the continuous operation. More than 105 CFU (colony forming unit) antigen-interacting phages were isolated with ~100% specificity from a phage library containing 3 × 109 individual members within 40 minutes of sorting using CMAIL. CMAIL is rapid, sensitive, specific, and does not employ washing, elution or magnetic beads. In conclusion, we have developed an efficient and cost-effective method for isolating and sorting affinity reagents involving phage display.

  8. The Algebra of Assortative Encounters and the Evolution of Cooperation

    OpenAIRE

    Bergstrom, Ted

    2001-01-01

    This paper explores the quantitative relation between non random, assortative matching and the maintenance of cooperative behavior under evolutionary dynamics. We consider a population of individuals who are \\hardwired" to play either cooperate or defect. They meet other individuals according to some random process and play their programmed strategy in a game of Prisoners' Dilemma. The type that gets the higher expected payoff reproduces more rapidly. We de¯ne an index of assortativity of en...

  9. Assortative and disassortative mixing investigated using the spectra of graphs

    CERN Document Server

    Jalan, Sarika

    2015-01-01

    We investigate the impact of degree-degree correlations on the spectra of networks. Even though density distributions exhibit drastic changes depending on the (dis)assortative mixing and the network architecture, the short range correlations in eigenvalues exhibit universal RMT predictions. The long range correlations turn out to be a measure of randomness in (dis)assortative networks. The analysis further provides insight in to the origin of high degeneracy at the zero eigenvalue displayed by majority of the biological networks.

  10. Managing assortment in terms of foreign economic activity of the enterprise trade

    Directory of Open Access Journals (Sweden)

    Sergei Udin

    2015-02-01

    Full Text Available Assortment management is the main task of trade enterprises. Assortment is a basic tool in the marketing mix, it affects the sales and distribution costs. Management of assortment is an important issue for interna-tional companies, because they have a high cost of export-import operations, and this fact influences the financial result. The article considers the information technology assortment management aimed at increas-ing turnover and reducing distribution costs by forming a balanced assortment structure.

  11. When Granny Is the Wolf: Understanding and Approaching College-aged Female Victims of Acquaintance Rape

    OpenAIRE

    Lam, Charlene; Roman, Brenda

    2009-01-01

    College is generally felt to be an exciting time in the lives of young people; however, some college-aged students find themselves in difficult situations. For young women especially, acquaintance rape in the college years is a risk. While men can also be victims of sexual assault, it is far more common for women to be victimized. This article reviews the literature of acquaintance rape, including situational risk factors, perpetrator characteristics, and victim characteristics, as well as st...

  12. Bridging across nations. The social capital of diversity, brokerage and closure in transnational migrant networks: a study on assimilation patterns in Milan and Barcelona

    OpenAIRE

    Vacca,, C.

    2013-01-01

    This dissertation deals with the network effects on immigrant assimilation: how the composition and structure of migrants' personal networks affect patterns of assimilation in host societies. A personal network is the set of all current and active social contacts that a focal individual (Ego) has, including family, friends and acquaintances. It is operationalized here as the list of 45 alters who were mentioned by Ego (the migrant) as people with whom he had some kind of contact in the las...

  13. Assortment structure in beech coppice stands in the Crni vrh region

    Directory of Open Access Journals (Sweden)

    Danilović Milorad

    2003-01-01

    Full Text Available Assortment structure in beech coppice stands was studied for the region of Crni vrh. Assortment structure was determined according to the standard (JUS in two ecological units. The study results show that the assortment value structure significantly increases with the increase of tree diameter and that there are no statistically significant differences in assortment structure between the selected ecological units. The dependence of the assortment value structure on tree diameter can be represented by an exponential function. The value percentage of assortments made of stem wood in theoretical crosscutting depending on tree diameter has an increasing tendency, except for the wood for excelsior.

  14. Assimilating atmosphere reanalysis in coupled data assimilation

    Science.gov (United States)

    Liu, Huaran; Lu, Feiyu; Liu, Zhengyu; Liu, Yun; Zhang, Shaoqing

    2016-06-01

    This paper tests the idea of substituting the atmospheric observations with atmospheric reanalysis when setting up a coupled data assimilation system. The paper focuses on the quantification of the effects on the oceanic analysis resulted from this substitution and designs four different assimilation schemes for such a substitution. A coupled Lorenz96 system is constructed and an ensemble Kalman filter is adopted. The atmospheric reanalysis and oceanic observations are assimilated into the system and the analysis quality is compared to a benchmark experiment where both atmospheric and oceanic observations are assimilated. Four schemes are designed for assimilating the reanalysis and they differ in the generation of the perturbed observation ensemble and the representation of the error covariance matrix. The results show that when the reanalysis is assimilated directly as independent observations, the root-mean-square error increase of oceanic analysis relative to the benchmark is less than 16% in the perfect model framework; in the biased model case, the increase is less than 22%. This result is robust with sufficient ensemble size and reasonable atmospheric observation quality (e.g., frequency, noisiness, and density). If the observation is overly noisy, infrequent, sparse, or the ensemble size is insufficiently small, the analysis deterioration caused by the substitution is less severe since the analysis quality of the benchmark also deteriorates significantly due to worse observations and undersampling. The results from different assimilation schemes highlight the importance of two factors: accurate representation of the error covariance of the reanalysis and the temporal coherence along each ensemble member, which are crucial for the analysis quality of the substitution experiment.

  15. Assimilation in multilingual cities

    OpenAIRE

    Ortega, Javier

    2011-01-01

    Using the Public Use Microdata Files of the 2001 and 2006 Canadian Censuses, we study the determinants of the assimilation of language minorities into the city majority language. We show that official minority members (i.e. francophones in English-speaking cities and anglophones in French-speaking cities) assimilate less than the "allophones" (the individuals with a mother tongue other than English or French), and that immigrants generally assimilate less than natives. In addition, the langua...

  16. Assimilation of Images

    OpenAIRE

    Vidard, Arthur; Titaud, Olivier

    2014-01-01

    International audience Data assimilation aims at determining as accurately as possible the state of a dynamical system by combining heterogeneous sources of information in an optimal way. Generally speaking, the mathematical methods of data assimilation describe algorithms for forming optimal combinations of observations of a system, a numerical model that describes its evolution, and appropriate prior information. Data assimilation has a long history of application to high-dimensional geo...

  17. Assortment and packaging of the segmented rotavirus genome.

    Science.gov (United States)

    McDonald, Sarah M; Patton, John T

    2011-03-01

    The rotavirus (RV) genome comprises 11 segments of double-stranded RNA (dsRNA) and is contained within a non-enveloped, icosahedral particle. During assembly, a highly coordinated selective packaging mechanism ensures that progeny RV virions contain one of each genome segment. Cis-acting signals thought to mediate assortment and packaging are associated with putative panhandle structures formed by base-pairing of the ends of RV plus-strand RNAs (+RNAs). Viral polymerases within assembling core particles convert the 11 distinct +RNAs to dsRNA genome segments. It remains unclear whether RV +RNAs are assorted before or during encapsidation, and the functions of viral proteins during these processes are not resolved. However, as reviewed here, recent insights gained from the study of RV and two other segmented RNA viruses, influenza A virus and bacteriophage Φ6, reveal potential mechanisms of RV assortment and packaging.

  18. Geometric Assortative Growth Model for Small-World Networks

    Directory of Open Access Journals (Sweden)

    Yilun Shang

    2014-01-01

    Full Text Available It has been shown that both humanly constructed and natural networks are often characterized by small-world phenomenon and assortative mixing. In this paper, we propose a geometrically growing model for small-world networks. The model displays both tunable small-world phenomenon and tunable assortativity. We obtain analytical solutions of relevant topological properties such as order, size, degree distribution, degree correlation, clustering, transitivity, and diameter. It is also worth noting that the model can be viewed as a generalization for an iterative construction of Farey graphs.

  19. Geometric assortative growth model for small-world networks.

    Science.gov (United States)

    Shang, Yilun

    2014-01-01

    It has been shown that both humanly constructed and natural networks are often characterized by small-world phenomenon and assortative mixing. In this paper, we propose a geometrically growing model for small-world networks. The model displays both tunable small-world phenomenon and tunable assortativity. We obtain analytical solutions of relevant topological properties such as order, size, degree distribution, degree correlation, clustering, transitivity, and diameter. It is also worth noting that the model can be viewed as a generalization for an iterative construction of Farey graphs.

  20. Lilium: breeding history of the modern cultivated assortment

    NARCIS (Netherlands)

    Tuyl, van J.M.; Arens, P.

    2011-01-01

    During the last 50 years the lily has become worldwide one of the most important flower bulbs and cut flowers. They are mainly cultivated in The Netherlands with bulb production acreage of more than 5000 ha. The assortment of lilies consists of thousands of cultivars which can be classified in diffe

  1. [Influence of seedling assortment on Panax notoginseng growth and yield].

    Science.gov (United States)

    Cui, X; Wang, C; Chen, Z

    1998-02-01

    Making Panax notoginseng seedling assortment according to seedling size before transplanting, the result shows that the influence is better, the yield of root tuber and fruit is higher. Culturing good seedling is the fundamental measure to increase yield of P. notoginseng.

  2. Unusual assortment of segments in 2 rare human rotavirus genomes.

    Science.gov (United States)

    De Grazia, Simona; Giammanco, Giovanni M; Potgieter, Christiaan A; Matthijnssens, Jelle; Banyai, Krisztian; Platia, Maria A; Colomba, Claudia; Martella, Vito

    2010-05-01

    Using full-length genome sequence analysis, we investigated 2 rare G3P[9] human rotavirus strains isolated from children with diarrhea. The genomes were recognized as assortments of genes closely related to rotaviruses originating from cats, ruminants, and humans. Results suggest multiple transmissions of genes from animal to human strains of rotaviruses.

  3. The Variety of An Assortment : An Extension to the Attribute-Based Approach

    NARCIS (Netherlands)

    Herpen, van H.W.I.; Pieters, F.G.M.

    2002-01-01

    In recent years, interest in category management has surged, and as a consequence, large retailers now systematically review their product assortments. Variety is a key property of assortments. Assortment variety can determine consumers' store choice and is only gaining in importance with today's in

  4. When Granny Is the Wolf: Understanding and Approaching College-aged Female Victims of Acquaintance Rape.

    Science.gov (United States)

    Lam, Charlene; Roman, Brenda

    2009-08-01

    College is generally felt to be an exciting time in the lives of young people; however, some college-aged students find themselves in difficult situations. For young women especially, acquaintance rape in the college years is a risk. While men can also be victims of sexual assault, it is far more common for women to be victimized. This article reviews the literature of acquaintance rape, including situational risk factors, perpetrator characteristics, and victim characteristics, as well as strategies to prevent revictimization, utilizing a female victim as the composite case. PMID:19763203

  5. Assortativity Effects on Diffusion-like Processes in Scale-free Networks

    CERN Document Server

    D'Agostino, Gregorio; Zlatić, Vinko; Caldarelli, Guido

    2011-01-01

    We study the variation in epidemic thresholds in complex networks with different assortativity properties. We determine the thresholds by applying spectral analysis to the matrices associated to the graphs. In order to produce graphs with a specific assortativity we introduce a procedure to sample the space of all the possible networks with a given degree sequence. Our analysis shows that while disassortative networks have an higher epidemiological threshold, assortative networks have a slower diffusion time for diseases. We also used these networks for evaluating the effects of assortativity in a specific dynamic model of sandpile. We show that immunization procedures give different results according to the assortativity of the network considered.

  6. An Acquaintance Rape Education Program for Students Transitioning to High School

    Science.gov (United States)

    Fay, Karen E.; Medway, Frederic J.

    2006-01-01

    Based on Parrot's work with college students, a six-activity acquaintance rape prevention program for first-year high school students living in a rural South Carolina community was implemented and evaluated. The program decreased students' acceptance of rape myths compared with non-participating students both on a scale developed by Burt and on…

  7. Acquaintance Rape Workshops: Their Effectiveness in Changing the Attitudes of First Year College Men

    Science.gov (United States)

    Earle, James P.

    2009-01-01

    The statistics on acquaintance rape and sexual assault against women are a clear indication that this is a problem that needs to be confronted. An increasing number of articles address the problems that rape survivors face and examine methods mental health professionals can use to assist survivors in dealing with these problems. Articles that…

  8. Date and Acquaintance Rape: The Legal Point of View. Part 1. The Traditional Law of Rape.

    Science.gov (United States)

    Julian, Frank H.

    1993-01-01

    First article in two-part series on date and acquaintance rape explains unique circumstances of rape trials and looks at development of traditional rape law. Examines judicial history of rape, and reviews elements of rape (penetration, intent, force, and consent). (Author/NB)

  9. Five Year Campus Acquaintance Rape Education: Evaluating the Impact of a Mandatory Intervention.

    Science.gov (United States)

    Lonsway, Kimberly A.; Kothari, Chevon

    2000-01-01

    Evaluated the impact of a mandatory acquaintance rape education program for college freshmen. Surveys of participating and nonparticipating students immediately and several months following the program indicated a positive impact of participation on attitudes and judgements immediately following participation. Increases in knowledge were…

  10. Acquaintance Rape and Alcohol Consumption on College Campuses: How Are They Linked?

    Science.gov (United States)

    Abbey, Antonia

    1991-01-01

    Explores the links between acquaintance rape and alcohol consumption among college students, two serious problems on campus. Seven explanations for the relationship focus on alcohol consumption by the perpetrator and by the victim. The need to conduct further studies and develop prevention programs is addressed. (Author/SM)

  11. Acquaintance Rape of College Students. Problem-Oriented Guides for Police Series.

    Science.gov (United States)

    Sampson, Rana

    Guides in this series summarize knowledge about how police can reduce the harm caused by specific crime and disorder problems. They are guides to prevention, not to investigating offenses of handling incidents. This guide focuses on rape of college students by acquaintances. It is estimated that almost 25% of college women have been victims of…

  12. Suggested Acquaintance/Date Rape Education & Prevention Strategies for School Health Instruction.

    Science.gov (United States)

    Weiler, Robert M.; Walls, Nicole A.

    Data suggest that acquaintance and date rape may account for 50-70 percent of all reported rapes in the United States. Recent findings also indicate that one in four college women have been raped or a victim of attempted rape. As most rape victims are between 15 and 24 years of age, high school-based education programs must be provided if society…

  13. The Impact of Acquaintance Rape Stories and Case-Specific Pretrial Publicity on Juror Decision Making.

    Science.gov (United States)

    Mullin, Charles; And Others

    1996-01-01

    Reports on a trial simulation in which exposure to publicity regarding the defendant and general stories about acquaintance rape were manipulated; participants then viewed an enacted rape trial. Finds that male subjects exposed to predatory rape publicity were pro-defendant, whereas women were unaffected. Discusses male reaction to information…

  14. Gender, Sex-Role Stereotypes, and the Attribution of Responsibility for Date and Acquaintance Rape.

    Science.gov (United States)

    Proite, Rosanne; And Others

    1993-01-01

    Examined college student attitudes toward women and attribution of responsibility for acquaintance rape. Findings from 417 students revealed that, in situations described in scenarios, male college students were more likely to assign responsibility to the woman. They more strongly believed that the woman wanted to have sexual intercourse and that…

  15. "Nobody Told Me It Was Rape": A Parent's Guide for Talking with Teenagers about Acquaintance Rape and Sexual Exploitation.

    Science.gov (United States)

    Adams, Caren; Fay, Jennifer

    This book was written to help parents talk to their adolescent children about acquaintance rape and sexual exploitation. It may also be useful to family life educators presenting units on rape and sexual exploitation. Acquaintance rape and sexual exploitation are explained in the first section. The second section discusses talking with teenagers…

  16. Differential Characteristics of Intimate Partner, Acquaintance, and Stranger Rape Survivors Examined by a Sexual Assault Nurse Examiner (SANE)

    Science.gov (United States)

    Logan, TK; Cole, Jennifer; Capillo, Anita

    2007-01-01

    Relatively little is known about characteristics of sexual assault survivors who present to the emergency room. Examination of differences in survivor, assault, and exam characteristics by type of offender (intimate partner, acquaintance, acquaintance-just-met, and stranger) was conducted using intake data collected from 331 women who presented to…

  17. An Acquaintance Rape Prevention Program: Effects on Attitudes Toward Women, Rape-Related Attitudes, and Perceptions of Rape Scenarios.

    Science.gov (United States)

    Pinzone-Glover, Holly A.; Gidycz, Christine A.; Jacobs, Cecilia Dine

    1998-01-01

    Studied the effects of an acquaintance-rape prevention program on college students' attitudes (n=152) toward rape and attitudes toward women, perceptions of acquaintance rape scenarios, and rape empathy. Positive attitude change was stronger among men, who became more certain of rape definitions. Contains 53 references. (SLD)

  18. The Effectiveness of Personalizing Acquaintance Rape Prevention: Programs on Perception of Vulnerability and on Reducing Risk-Taking Behavior.

    Science.gov (United States)

    Gray, Michael D.; And Others

    1990-01-01

    Tested hypothesis that a personalized acquaintance rape prevention program reduces risk-taking behavior and increases perception of vulnerability. Seventy female college students were exposed to Acquaintance Rape Prevention Program with experimentals and controls receiving personalized or nonpersonalized instruction, respectively. Findings showed…

  19. Displacement Data Assimilation

    CERN Document Server

    Rosenthal, W Steven; Mariano, Arthur J; Restrepo, Juan M

    2016-01-01

    We show that modifying a Bayesian data assimilation scheme by incorporating kinematically-consistent displacement corrections produces a scheme that is demonstrably better at estimating partially observed state vectors in a setting where feature information important. While the displacement transformation is not tied to any particular assimilation scheme, here we implement it within an ensemble Kalman Filter and demonstrate its effectiveness in tracking stochastically perturbed vortices.

  20. Evaluating Data Assimilation Algorithms

    CERN Document Server

    Law, K J H

    2011-01-01

    Data assimilation refers to methodologies for the incorporation of noisy observations of a physical system into an underlying model in order to infer the properties of the state of the system (and/or parameters). The model itself is typically subject to uncertainties, in the input data and in the physical laws themselves. This leads naturally to a Bayesian formulation in which the posterior probability distribution of the system state, given the observations, plays a central conceptual role. The aim of this paper is to use this Bayesian posterior probability distribution as a gold standard against which to evaluate various commonly used data assimilation algorithms. A key aspect of geophysical data assimilation is the high dimensionality of the computational model. With this in mind, yet with the goal of allowing an explicit and accurate computation of the posterior distribution in order to facilitate our evaluation, we study the 2D Navier-Stokes equations in a periodic geometry. We compute the posterior prob...

  1. The role of race and respectability in attributions of responsibility for acquaintance rape.

    Science.gov (United States)

    Dupuis, Erin C; Clay, Jason A

    2013-01-01

    Previous researchers have explored the role of race and respectability, independently, on attributions of responsibility; however, the interaction between race and respectability has not been analyzed in situations of acquaintance rape. Participants (N = 241) read a vignette detailing a case of acquaintance rape that manipulated the race of both the victim and the perpetrator and the respectability of the victim. Regression and ANOVA analyses indicated that victim race and respectability interacted in such a way that when Black victims were respectable, they were held less responsible than respectable White victims; however, less respected Black victims were held more responsible than less respected White victims. Manipulating perpetrator race revealed surprising results; the White perpetrator was found guilty more often than the Black perpetrator (although this appeared to be related to victim race). PMID:24547682

  2. Reflective acquaintance with other minds and the double-sided disclosure of the lived-body

    DEFF Research Database (Denmark)

    Farley, Adam

    2015-01-01

    This paper will consider the phenomenological disclosure of the reflecting-body vis-à-vis subject’s reflective acquaintance with other minds. To this end, phenomenological accounts regarding the double-sided disclosure of the lived-body will be expounded and developed. It will be argued...... that the latter can, and must, be considered as synchronously disclosed across the subject’s pre-reflective and reflective modes of acquaintance. Further, in order to maintain the distinction between these modes, it will be argued that a differential configuration of the lived-body’s double-sidedness must...... be admitted across these modes. To this end, observations regarding the lived disclosure of reflective acts vis-à-vis their embodied conduct are provided; suggesting that a partial inversion of the lived-body’s double-sidedness occurs during the transition to the reflective mode. Directions for future...

  3. Romantic Partners, Friends, Friends with Benefits, and Casual Acquaintances As Sexual Partners

    OpenAIRE

    Furman, Wyndol; Shaffer, Laura

    2011-01-01

    The purpose of the present study was to provide a detailed examination of sexual behavior with different types of partners. A sample of 163 young adults reported on their light nongenital, heavy nongenital, and genital sexual activity with romantic partners, friends, and casual acquaintances. They described their sexual activity with “friends with benefits” as well as with friends in general. Young adults were most likely to engage in sexual behavior with romantic partners, but sexual behavio...

  4. Judge me, judge me not: The role of eye size and observer gender on acquaintance rape

    OpenAIRE

    María Clara Ferrão; Gabriela Gonçalves; Jean Christophe Giger; Tiago Parreira

    2016-01-01

    The purpose of this study was to examine the effect of eye size and observer gender on perceived initial attraction, honesty, and attributions of responsibility for rape. A 3 (eye size: small vs. normal vs. large) x 2 (observer gender: female vs. male) experimental design was tested. Ninety participants (45 women and 45 men) observed one of three randomly assigned female faces (with eye size manipulation), and rated initial attraction and honesty. They were then asked to read an acquaintance ...

  5. Women’s Situational Coping With Acquaintance Sexual Assault: Applying an Appraisal-Based Model

    OpenAIRE

    Nurius, Paula S.; Norris, Jeanette; Macy, Rebecca J.; Huang, Bu

    2004-01-01

    Drawing on theories of appraisal-based coping, the present study applied structural modeling to examine relationships among personal goal orientations, primary and secondary appraisals of acquaintance sexual assault, and women’s emotional and behavioral responses to it. Based on 415 college women’s reports of a sexual assault experience, the model shows both direct and indirect effects. Assertive, diplomatic, and immobilized responding were each predicted by a unique profile of appraisals and...

  6. Optimality in Data Assimilation

    Science.gov (United States)

    Nearing, Grey; Yatheendradas, Soni

    2016-04-01

    It costs a lot more to develop and launch an earth-observing satellite than it does to build a data assimilation system. As such, we propose that it is important to understand the efficiency of our assimilation algorithms at extracting information from remote sensing retrievals. To address this, we propose that it is necessary to adopt completely general definition of "optimality" that explicitly acknowledges all differences between the parametric constraints of our assimilation algorithm (e.g., Gaussianity, partial linearity, Markovian updates) and the true nature of the environmetnal system and observing system. In fact, it is not only possible, but incredibly straightforward, to measure the optimality (in this more general sense) of any data assimilation algorithm as applied to any intended model or natural system. We measure the information content of remote sensing data conditional on the fact that we are already running a model and then measure the actual information extracted by data assimilation. The ratio of the two is an efficiency metric, and optimality is defined as occurring when the data assimilation algorithm is perfectly efficient at extracting information from the retrievals. We measure the information content of the remote sensing data in a way that, unlike triple collocation, does not rely on any a priori presumed relationship (e.g., linear) between the retrieval and the ground truth, however, like triple-collocation, is insensitive to the spatial mismatch between point-based measurements and grid-scale retrievals. This theory and method is therefore suitable for use with both dense and sparse validation networks. Additionally, the method we propose is *constructive* in the sense that it provides guidance on how to improve data assimilation systems. All data assimilation strategies can be reduced to approximations of Bayes' law, and we measure the fractions of total information loss that are due to individual assumptions or approximations in the

  7. The Sex and the Uni: Educational Assortative Matching the Over-Education*

    OpenAIRE

    Alessandro Tampieri

    2010-01-01

    Educational assortative matching encourages individuals to acquire education so as to increase the probability of marrying a high-income partner. But since everyone is more educated, the chances of a good match do not change. Hence over education emerges, as in absence of educational assortative matching individuals could reach their optimal level of education by exploiting less educational resources. Over-education is stronger the higher the probability of educational assortative matching, t...

  8. On Assimilation of English Sounds

    Institute of Scientific and Technical Information of China (English)

    刘恩华

    2015-01-01

    This paper makes a careful study of assimilation in English speaking, meanwhile a systematic knowledge of assimilation wil be helpful for the pronunciations of English learners, facilitate English fluency and improve listening comprehension.

  9. Reconsidering the heritability of intelligence in adulthood: taking assortative mating and cultural transmission into account.

    Science.gov (United States)

    Vinkhuyzen, Anna A E; van der Sluis, Sophie; Maes, Hermine H M; Posthuma, Danielle

    2012-03-01

    Heritability estimates of general intelligence in adulthood generally range from 75 to 85%, with all heritability due to additive genetic influences, while genetic dominance and shared environmental factors are absent, or too small to be detected. These estimates are derived from studies based on the classical twin design and are based on the assumption of random mating. Yet, considerable positive assortative mating has been reported for general intelligence. Unmodeled assortative mating may lead to biased estimates of the relative magnitude of genetic and environmental factors. To investigate the effects of assortative mating on the estimates of the variance components of intelligence, we employed an extended twin-family design. Psychometric IQ data were available for adult monozygotic and dizygotic twins, their siblings, the partners of the twins and siblings, and either the parents or the adult offspring of the twins and siblings (N = 1314). Two underlying processes of assortment were considered: phenotypic assortment and social homogamy. The phenotypic assortment model was slightly preferred over the social homogamy model, suggesting that assortment for intelligence is mostly due to a selection of mates on similarity in intelligence. Under the preferred phenotypic assortment model, the variance of intelligence in adulthood was not only due to non-shared environmental (18%) and additive genetic factors (44%) but also to non-additive genetic factors (27%) and phenotypic assortment (11%).This non-additive nature of genetic influences on intelligence needs to be accommodated in future GWAS studies for intelligence.

  10. Assortative marriages by body mass index have increased simultaneously with the obesity epidemic

    DEFF Research Database (Denmark)

    Adeltoft, Teresa Ajslev; Ängquist, Lars Henrik; Silventoinen, Karri;

    2012-01-01

    Background: The genetic predisposition to obesity may have contributed to the obesity epidemic through assortative mating. We investigated whether spouses were positively assorted by body mass index (BMI; = kg/m(2)) in late childhood, and whether changes in assorted marriage by upper BMI...... percentile were higher and increased more; from 1.39, 1.10-1.81, to 2.39, 1.85-3.09 (p = 0.004). Interpretation: Spousal correlations by pre-marital BMIs were small and stable during the past 65 years. Yet, there were assorted marriages between spouses with high BMI at age 13 years and the tendency increased...

  11. Detecting network communities beyond assortativity-related attributes

    Science.gov (United States)

    Liu, Xin; Murata, Tsuyoshi; Wakita, Ken

    2014-07-01

    In network science, assortativity refers to the tendency of links to exist between nodes with similar attributes. In social networks, for example, links tend to exist between individuals of similar age, nationality, location, race, income, educational level, religious belief, and language. Thus, various attributes jointly affect the network topology. An interesting problem is to detect community structure beyond some specific assortativity-related attributes ρ, i.e., to take out the effect of ρ on network topology and reveal the hidden community structures which are due to other attributes. An approach to this problem is to redefine the null model of the modularity measure, so as to simulate the effect of ρ on network topology. However, a challenge is that we do not know to what extent the network topology is affected by ρ and by other attributes. In this paper, we propose a distance modularity, which allows us to freely choose any suitable function to simulate the effect of ρ. Such freedom can help us probe the effect of ρ and detect the hidden communities which are due to other attributes. We test the effectiveness of distance modularity on synthetic benchmarks and two real-world networks.

  12. Palindromes drive the re-assortment in Influenza A.

    Science.gov (United States)

    Zubaer, Abdullah; Thapa, Simrika

    2011-01-01

    Different subtypes of Influenza A virus are associated with species specific, zoonotic or pandemic Influenza. The cause of its severity underlies in complicated evolution of its segmented RNA genome. Although genetic shift and genetic drift are well known in the evolution of this virus, we reported the significant role of unique RNA palindromes in its evolution. Our computational approach identified the existence of unique palindromes in each subtype of Influenza A virus with its absence in Influenza B relating the fact of virulence and vigorous genetic hitchhiking in Influenza A. The current study focused on the re-assortment event responsible for the emergence of pandemic-2009 H1N1 virus, which is associated with outgrow of new palindrome and in turn, changing its RNA structure. We hypothesize that the change in RNA structure due to the presence of palindrome facilitates the event of re-assortment in Influenza A. Thus the evolutionary process of Influenza A is much more complicated as previously known, and that has been demonstrated in this study.

  13. The role of active assortment in spousal similarity.

    Science.gov (United States)

    Watson, David; Beer, Andrew; McDade-Montez, Elizabeth

    2014-04-01

    Previous research has established the existence of active assortment, that is, a preference for similarity in a potential mate. Few studies, however, have directly related mate preferences to dyadic similarity by examining them in the same participants. We collected both similarity and mate preference data in two studies: undergraduate students (N = 519) and newlyweds (N = 335). In both studies, women placed a higher value on desirable personality characteristics (e.g., higher Conscientiousness and Agreeableness, lower Neuroticism) than did men. Nevertheless, our data also provided strong evidence of consensual mate preferences: Men and women both desired partners who were agreeable, conscientious, emotionally stable, intelligent, and physically attractive; furthermore, participants desired partners who were better (e.g., more agreeable and attractive) than they were. In contrast, attitudinal variables such as religiousness and political orientation displayed much weaker consensus but showed significant dyadic similarity in both samples; similarity coefficients for personality tended to be positive, but lower. Finally, analyses revealed a direct link between actual and desired similarity: Couples displayed the strongest similarity on those variables for which participants expressed the strongest preference for similarity. Our findings strongly suggest that active assortment is partly responsible for dyadic similarity.

  14. Explosive Synchronization and Emergence of Assortativity on Adaptive Networks

    Institute of Scientific and Technical Information of China (English)

    JIANG Hui-Jun; WU Hao; HOU Zhong-Huai

    2011-01-01

    @@ We report an explosive transition from incoherence to synchronization of coupled phase oscillators on adaptive networks,following an Achlioptas process based on dynamic clustering information.During each adaptive step of the network topology,a portion of the links is randomly removed and the same amount of new links is generated following the so-called product rules(PRs) applied to the dynamic clusters.Particularly,two types of PRs are considered,namely,the min-PR and max-PR.We demonstrate that the synchronization transition becomes explosive in both cases.Interestingly,we find that the min-PR rule can lead to disassortativity of the network topology,while the max-PR rule leads to assortativity.%We report an explosive transition from incoherence to synchronization of coupled phase oscillators on adaptive networks, following an Achlioptas process based on dynamic clustering information. During each adaptive step of the network topology, a portion of the links is randomly removed and the same amount of new links is generated following the so-called product rules (PRs) applied to the dynamic clusters. Particularly, two types of PRs are considered, namely, the min-PR and max-PR. We demonstrate that the synchronization transition becomes explosive in both cases. Interestingly, we find that the min-PR rule can lead to disassortativity of the network topology, while the max-PR rule leads to assortativity.

  15. Assimilation in multilingual cities

    OpenAIRE

    Ortega, Javier; Verdugo, Gregory

    2015-01-01

    International audience We characterise how the assimilation patterns of minorities into the strong and the weak language differ in a situation of asymmetric bilingualism. Using large variations in language composition in Canadian cities from the 2001 and 2006 Censuses, we show that the differences in the knowledge of English by immigrant allophones (i.e. the immigrants with a mother tongue other than English and French) in English-majority cities are mainly due to sorting across cities. In...

  16. Over-Education and Assortative Matching in Partnerships: A Theoretical Analysis

    Science.gov (United States)

    Tampieri, Alessandro

    2016-01-01

    This paper argues that assortative matching may explain over-education. Education determines individuals' income and, due to the presence of assortative matching, the quality of partners in personal, social and working life. Thus, an individual acquires education to improve the expected partners' quality. However, since every individual of the…

  17. Innovative approaches to the prices management within the framework of product assortment

    Directory of Open Access Journals (Sweden)

    O.I. Laburtseva

    2011-03-01

    Full Text Available The article is devoted to the development of methodical recommendations on a products prices management with presence of substitution or complementation connections in the product assortment. The variants of product intercommunications in the assortment of enterprise are systematized, the proper methodical approaches to pricing are recommended and the results of business-approbation of recommendations are presented.

  18. Methods of forming and realization of assortment policy of retail business enterprises

    Directory of Open Access Journals (Sweden)

    Kudenko Kiril

    2016-07-01

    Full Text Available Within the framework of the article systematisation of methods of forming and realisation of assortment policy of enterprises of retail business is done. Recommendations concerning the priority of the use of separate methods of forming and realisation of assortment policy with different purposes, taking into account their content, advantages and disadvantages are developed.

  19. ASESMENT POST TRAUMATIC STRESS DISORDER (PTSD PADA PEREMPUAN KORBAN PERKOSAAN (ACQUAINTANCE RAPE

    Directory of Open Access Journals (Sweden)

    Mutingatu Solichah

    2013-08-01

    Full Text Available AbstractThis research was intended to find out whether Post Traumatic Stress Disorder (PTSD symptom manifested in 5 women acquaintance rape survivors.PTSD Symptom was measured by the Clinician-Administered PTSD Scale (CAPS, a semi structured interview guide that assesses 17 clinical symptoms of PTSD outlines in DSM IV criterion along with 3 associated features of PTSD symptoms. Quantitative data is used todetermine the categorical rating of the PTSD diagnostic status of the participants (PTSD present or absent, symptom severity, and changes gradations of symptom severity over time. Participants were 5 women survivors of acquaintance rape, aged 17 – 35 years old. The results show 4 from 5 participants was diagnosed having PTSD which symptom severity varied. The CAPS’ PTSD diagnostic procedure is combined between the DSM IV defined 20 symptom criteria and its symptom’s frequency and intensity, so the score should range from 20 the lowest up to 160. The participants score range from 35– 125, but one participant was not eligiblefor PTSD diagnostic status due to failure to meet DSM IV criterion for PTSD. The interval time between the traumatic event (rape and research was ranging from 4 to 31 years, however PTSD symptom’s severity in participants remain high.Keywords: acquaintance rape, Clinician-Administered PTSD Scale (CAPS, DSM IV.

  20. Young heterosexual men’s use of the miscommunication model in explaining acquaintance rape

    OpenAIRE

    Hansen, Susan; O'Byrne, Racheal; Rapley, Mark

    2010-01-01

    This article describes a program of research that systematically examined the ways in which young heterosexual men draw on widely culturally shared accounts of rape to account for sexual coercion and sexual assault. In particular, the authors discuss the reliance placed on a lay version of Tannen’s (1992) miscommunication model of (acquaintance) rape—the claim that rape is a consequence of men’s not knowing—and young men’s use of this account as a device to accomplish exculpation. The authors...

  1. ASESMENT POST TRAUMATIC STRESS DISORDER (PTSD) PADA PEREMPUAN KORBAN PERKOSAAN (ACQUAINTANCE RAPE)

    OpenAIRE

    Mutingatu Solichah

    2013-01-01

    AbstractThis research was intended to find out whether Post Traumatic Stress Disorder (PTSD) symptom manifested in 5 women acquaintance rape survivors.PTSD Symptom was measured by the Clinician-Administered PTSD Scale (CAPS), a semi structured interview guide that assesses 17 clinical symptoms of PTSD outlines in DSM IV criterion along with 3 associated features of PTSD symptoms. Quantitative data is used todetermine the categorical rating of the PTSD diagnostic status of the participan...

  2. Colour assortative pairing in a colour polymorphic lizard is independent of population morph diversity

    Science.gov (United States)

    Pérez i de Lanuza, Guillem; Font, Enrique; Carretero, Miguel Ángel

    2016-10-01

    Previous work with a colour polymorphic population of Podarcis muralis (Lacertidae) revealed that lizards pair by ventral colour, favouring the same colour (i.e. homomorphic) pairs. Such assortative pairing, which probably results in colour assortative mating, can have consequences for the genetic structure of the population and potentially promote speciation. The population previously studied, located in the Pyrenees, encompasses white, yellow and orange animals, as well as intermediate white-orange and yellow-orange morphs. However, other Pyrenean populations of P. muralis have less ventral colour morphs. Our aim in this study is to test the generality of the assortative colour pairing system, extending our previous analyses to populations with different morph compositions and frequencies. The results show that the assortative pattern of pairing is similar in all the populations analysed and, hence, independent of morph composition and not restricted to pentamorphic populations. This suggests that assortative pairing by colour is a general phenomenon for colour polymorphic populations of P. muralis.

  3. Predation risk as a driving force for phenotypic assortment: a cross-population comparison.

    Science.gov (United States)

    Croft, D P; Darden, S K; Ruxton, G D

    2009-05-22

    Frequency-dependent predation has been proposed as a general mechanism driving the phenotypic assortment of social groups via the 'oddity effect', which occurs when the presence of odd individuals in a group allows a predator to fixate on a single prey item, increasing the predator's attack-to-kill ratio. However, the generality of the oddity effect has been debated and, previously, there has not been an ecological assessment of the role of predation risk in driving the phenotypic assortment of social groups. Here, we compare the levels of body length assortment of social groups between populations of the Trinidadian guppy (Poecilia reticulata) that experience differences in predation risk. As predicted by the oddity effect hypothesis, we observe phenotypic assortment by body length to be greater under high predation risk. However, we found that a number of low-predation populations were also significantly assorted by body length, suggesting that other mechanisms may have a role to play.

  4. Inducing Self-Organized Criticality in a network toy model by neighborhood assortativity

    CERN Document Server

    Allen-Perkins, Alfonso; Pastor, Juan Manuel

    2016-01-01

    Complex networks are a recent type of frameworks used to study complex systems with many interacting elements, such as Self-Organized Criticality (SOC). The network node's tendency to link to other nodes of similar type is characterized by assortative mixing. Real networks exhibit assortative mixing by vertex degree, however typical random network models, such as Erdos-Renyi or Barabasi-Albert, show no assortative arrangements. In this paper we introduce the neighborhood assortativity notion, as the tendency of a node to belong to a community (its neighborhood) showing an average property similar to its own. Imposing neighborhood assortative mixing by degree in a network toy model, SOC dynamics can be found. The long-range correlations resulting from the criticality have been characterized by means of fluctuation analysis and show an anticorrelation in the node's activity. The model contains only one parameter and its statistics plots for different values of the parameter can be collapsed into a single curve....

  5. Snow Radiance Assimilation Studies

    Science.gov (United States)

    Kim, E. J.; Durand, M. T.; Toure, A.; Margulis, S. A.; Goita, K.; Royer, A.; Lu, H.

    2009-12-01

    Passive microwave-based retrievals of terrestrial snow parameters from satellite observations form a 30-year global record which will continue for the forseeable future. So far, these snow retrievals have been generated primarily by regression-based empirical “inversion” methods based on snapshots in time, and are limited to footprints around 25 km in diameter. Assimilation of microwave radiances into physical land surface models may be used to create a retrieval framework that is inherently self-consistent with respect to model physics as well as a more physically-based approach vs. legacy retrieval/inversion methods. This radiance assimilation approach has been used for years for atmospheric parameters by the operational weather forecasting community with great success, and represents one motivation for our work. A radiance assimilation scheme for snow requires a snowpack land surface model (LSM) coupled to a radiative transfer model (RTM). In previous local-scale studies, Durand, Kim, & Margulis (2008) explored the requirements on LSM model fidelity (i.e., snowpack state information) required in order for the RTM to produce brightness temperatures suitable for radiance assimilation purposes at a local scale, using the well-known Microwave Emission Model for Layered Snowpacks (MEMLS) as the RTM and a combination of Simple SIB (SSiB) and Snow Atmosphere (SAST) as the LSM. They also demonstrated improvement of simulated snow depth through the use of an ensemble Kalman filter scheme at this local scale (2009). This modeling framework reflects another motivation—namely, possibilities for downscaling. Our focus at this stage has been at the local scale where high-quality ground truth data is available in order to evaluate radiance assimilation under a “best case scenario.” The quantitative results then form a benchmark for future assessment of effects such as sparse forcing data, upscaling/downscaling, forest attenuation, and model details. Field data from

  6. Phenotypic robustness and the assortativity signature of human transcription factor networks.

    Directory of Open Access Journals (Sweden)

    Dov A Pechenick

    2014-08-01

    Full Text Available Many developmental, physiological, and behavioral processes depend on the precise expression of genes in space and time. Such spatiotemporal gene expression phenotypes arise from the binding of sequence-specific transcription factors (TFs to DNA, and from the regulation of nearby genes that such binding causes. These nearby genes may themselves encode TFs, giving rise to a transcription factor network (TFN, wherein nodes represent TFs and directed edges denote regulatory interactions between TFs. Computational studies have linked several topological properties of TFNs - such as their degree distribution - with the robustness of a TFN's gene expression phenotype to genetic and environmental perturbation. Another important topological property is assortativity, which measures the tendency of nodes with similar numbers of edges to connect. In directed networks, assortativity comprises four distinct components that collectively form an assortativity signature. We know very little about how a TFN's assortativity signature affects the robustness of its gene expression phenotype to perturbation. While recent theoretical results suggest that increasing one specific component of a TFN's assortativity signature leads to increased phenotypic robustness, the biological context of this finding is currently limited because the assortativity signatures of real-world TFNs have not been characterized. It is therefore unclear whether these earlier theoretical findings are biologically relevant. Moreover, it is not known how the other three components of the assortativity signature contribute to the phenotypic robustness of TFNs. Here, we use publicly available DNaseI-seq data to measure the assortativity signatures of genome-wide TFNs in 41 distinct human cell and tissue types. We find that all TFNs share a common assortativity signature and that this signature confers phenotypic robustness to model TFNs. Lastly, we determine the extent to which each of the four

  7. Phenotypic robustness and the assortativity signature of human transcription factor networks.

    Science.gov (United States)

    Pechenick, Dov A; Payne, Joshua L; Moore, Jason H

    2014-08-01

    Many developmental, physiological, and behavioral processes depend on the precise expression of genes in space and time. Such spatiotemporal gene expression phenotypes arise from the binding of sequence-specific transcription factors (TFs) to DNA, and from the regulation of nearby genes that such binding causes. These nearby genes may themselves encode TFs, giving rise to a transcription factor network (TFN), wherein nodes represent TFs and directed edges denote regulatory interactions between TFs. Computational studies have linked several topological properties of TFNs - such as their degree distribution - with the robustness of a TFN's gene expression phenotype to genetic and environmental perturbation. Another important topological property is assortativity, which measures the tendency of nodes with similar numbers of edges to connect. In directed networks, assortativity comprises four distinct components that collectively form an assortativity signature. We know very little about how a TFN's assortativity signature affects the robustness of its gene expression phenotype to perturbation. While recent theoretical results suggest that increasing one specific component of a TFN's assortativity signature leads to increased phenotypic robustness, the biological context of this finding is currently limited because the assortativity signatures of real-world TFNs have not been characterized. It is therefore unclear whether these earlier theoretical findings are biologically relevant. Moreover, it is not known how the other three components of the assortativity signature contribute to the phenotypic robustness of TFNs. Here, we use publicly available DNaseI-seq data to measure the assortativity signatures of genome-wide TFNs in 41 distinct human cell and tissue types. We find that all TFNs share a common assortativity signature and that this signature confers phenotypic robustness to model TFNs. Lastly, we determine the extent to which each of the four components of the

  8. A framework for analyzing contagion in assortative banking networks

    CERN Document Server

    Hurd, Thomas R; Melnik, Sergey

    2016-01-01

    We introduce a probabilistic framework that represents stylized banking networks with the aim of predicting the size of contagion events. Most previous work on random financial networks assumes independent connections between banks, whereas our framework explicitly allows for (dis)assortative edge probabilities (e.g., a tendency for small banks to link to large banks). We analyze default cascades triggered by shocking the network and find that the cascade can be understood as an explicit iterated mapping on a set of edge probabilities that converges to a fixed point. We derive a cascade condition that characterizes whether or not an infinitesimal shock to the network can grow to a finite size cascade, in analogy to the basic reproduction number $R_0$ in epidemic modelling. The cascade condition provides an easily computed measure of the systemic risk inherent in a given banking network topology. Using the percolation theory for random networks we also derive an analytic formula for the frequency of global cas...

  9. A survey on acquaintance, orientation and behavior of general medical practitioners toward periodontal diseases

    Directory of Open Access Journals (Sweden)

    Supreet Kaur

    2015-01-01

    Full Text Available Background: An association between oral conditions such as periodontal diseases and systemic conditions is noted. As such, periodontal disease is associated with an increased risk of systemic illnesses such as cardiovascular disease, diabetes, adverse pregnancy outcome, atherosclerosis, stroke and hospital acquired pneumonia. The concept of diagnosing and treating a potential patient to minimize the deleterious effects of this chronic infectious and inflammatory condition on systemic conditions represents both an unprecedented challenge and opportunity to our profession. Keeping this in view, the present survey was designed to evaluate the acquaintance, orientation and behavior of general medical practitioners; concerning the effects of periodontal disease on systemic health. Materials and Methods: A typed questionnaire carrying four sets of questions was distributed among general medical practitioners of seven different government and private medical colleges and hospitals. Questionnaire was developed to assess the acquaintance, orientation and behavior of general medical practitioners toward periodontal disease. Results: Most of the respondents have knowledge regarding the signs and symptoms of periodontal disease and its association with cardiovascular disease. However, majority of them do not know about the potential effect of periodontal disease on other organ systems. Conclusion: General medical practitioners have inadequate knowledge regarding periodontal diseases. Hence, oral health related training should be an integral part of the medical curriculum.

  10. Data assimilation in hydrological modelling

    OpenAIRE

    Drecourt, Jean-Philippe; Rosbjerg, Dan

    2004-01-01

    Data assimilation is an invaluable tool in hydrological modelling as it allows to efficiently combine scarce data with a numerical model to obtain improved model predictions. In addition, data assimilation also provides an uncertainty analysis of the predictions made by the hydrological model. In this thesis, the Kalman filter is used for data assimilation with a focus on groundwater modelling. However the developed techniques are general and can be applied also in other modelling domains. Mo...

  11. Assimilation: central and peripheral effects

    OpenAIRE

    Weert, C.M.M. de; Kruysbergen, N.A.W.H. van

    1997-01-01

    Assimilation and contrast have opposite effects: Contrast leads to an increase of perceived differences between neighbouring fields, whereas assimilation leads to a reduction. It is relatively easy to demonstrate these effects, but the precise localisation of these effects in the perceptual system is not yet possible. In an experiment the strength of assimilation effects was modified by adding spatial noise. By varying the localisation in perceived space of the added noise (by presentation of...

  12. Regional Ocean Data Assimilation

    KAUST Repository

    Edwards, Christopher A.

    2015-01-03

    This article reviews the past 15 years of developments in regional ocean data assimilation. A variety of scientific, management, and safety-related objectives motivate marine scientists to characterize many ocean environments, including coastal regions. As in weather prediction, the accurate representation of physical, chemical, and/or biological properties in the ocean is challenging. Models and observations alone provide imperfect representations of the ocean state, but together they can offer improved estimates. Variational and sequential methods are among the most widely used in regional ocean systems, and there have been exciting recent advances in ensemble and four-dimensional variational approaches. These techniques are increasingly being tested and adapted for biogeochemical applications.

  13. Integrated Data Assimilation Architecture Project

    Data.gov (United States)

    National Aeronautics and Space Administration — The Integrated Data Assimilation Architecture (IDAA) is a middleware architecture that facilitates the incorporation of heterogeneous sensing and control devices...

  14. Integrated Data Assimilation Architecture Project

    Data.gov (United States)

    National Aeronautics and Space Administration — The Integrated Data Assimilation Architecture (IDAA) addresses the fundamental problem of command, control, and communications systems interoperability....

  15. Assimilation Dynamic Network (ADN) Project

    Data.gov (United States)

    National Aeronautics and Space Administration — The Assimilation Dynamic Network (ADN) is a dynamic inter-processor communication network that spans heterogeneous processor architectures, unifying components,...

  16. Determination of timber assortments obtainable from coppice chestnut stands (Susa Valley, Northern Italy

    Directory of Open Access Journals (Sweden)

    Nosenzo A

    2007-01-01

    Full Text Available Chestnut (Castanea sativa L. coppice stands currently cover about 195.000 ha of Piedmont (North-Western Italy surface, corresponding to 22.4 % of the overall forested area in the region. Most of these forest stands are usually older than the typical rotation period. As a consequence from these stands timber assortments with a higher value could be obtained. The purpose of this study is to assess the amount of timber assortments and to propose a sorting methodology based on measurements on standing trees within these chestnut stands.Five study areas were selected in the Susa Valley, where forest measurements were realized within sampling plots. Timber assortments obtainable from each coppice shoot were then determined by means of the Bitterlich’s relascope. More than 1.000 timber logs were measured. The data elaboration allowed to assess the timber assortment production of the investigated stands. The proposed methodology makes it possible to better exploit timber assortments. In fact, while usually the whole production from chestnut coppices is directly destined to secondary products, the subdivision into assortments could result in a 20 % of products with higher commercial value. It is important to notice that within these stands no tending operation is currently realized. The definition of qualitative features to classify timber assortments can provide useful suggestions on the main yield targets that could be reached through silvicultural management.

  17. Assimilating seizure dynamics.

    Science.gov (United States)

    Ullah, Ghanim; Schiff, Steven J

    2010-05-01

    Observability of a dynamical system requires an understanding of its state-the collective values of its variables. However, existing techniques are too limited to measure all but a small fraction of the physical variables and parameters of neuronal networks. We constructed models of the biophysical properties of neuronal membrane, synaptic, and microenvironment dynamics, and incorporated them into a model-based predictor-controller framework from modern control theory. We demonstrate that it is now possible to meaningfully estimate the dynamics of small neuronal networks using as few as a single measured variable. Specifically, we assimilate noisy membrane potential measurements from individual hippocampal neurons to reconstruct the dynamics of networks of these cells, their extracellular microenvironment, and the activities of different neuronal types during seizures. We use reconstruction to account for unmeasured parts of the neuronal system, relating micro-domain metabolic processes to cellular excitability, and validate the reconstruction of cellular dynamical interactions against actual measurements. Data assimilation, the fusing of measurement with computational models, has significant potential to improve the way we observe and understand brain dynamics. PMID:20463875

  18. Assimilating seizure dynamics.

    Directory of Open Access Journals (Sweden)

    Ghanim Ullah

    2010-05-01

    Full Text Available Observability of a dynamical system requires an understanding of its state-the collective values of its variables. However, existing techniques are too limited to measure all but a small fraction of the physical variables and parameters of neuronal networks. We constructed models of the biophysical properties of neuronal membrane, synaptic, and microenvironment dynamics, and incorporated them into a model-based predictor-controller framework from modern control theory. We demonstrate that it is now possible to meaningfully estimate the dynamics of small neuronal networks using as few as a single measured variable. Specifically, we assimilate noisy membrane potential measurements from individual hippocampal neurons to reconstruct the dynamics of networks of these cells, their extracellular microenvironment, and the activities of different neuronal types during seizures. We use reconstruction to account for unmeasured parts of the neuronal system, relating micro-domain metabolic processes to cellular excitability, and validate the reconstruction of cellular dynamical interactions against actual measurements. Data assimilation, the fusing of measurement with computational models, has significant potential to improve the way we observe and understand brain dynamics.

  19. Assimilate Partitioning and Plant Development

    Institute of Scientific and Technical Information of China (English)

    Yong-Ling Ruan; John W.Patrick; Hans Weber

    2010-01-01

    @@ It has been a pleasure to organize this special issue of Molecular Plant on 'Assimilate Partitioning and Plant Development'. Assimilate, a collective term describing organic carbon (C) and nitrogen (N), is of paramount importance for plant development and realization of crop productivity.

  20. Judge me, judge me not: The role of eye size and observer gender on acquaintance rape

    Directory of Open Access Journals (Sweden)

    María Clara Ferrão

    2016-01-01

    Full Text Available The purpose of this study was to examine the effect of eye size and observer gender on perceived initial attraction, honesty, and attributions of responsibility for rape. A 3 (eye size: small vs. normal vs. large x 2 (observer gender: female vs. male experimental design was tested. Ninety participants (45 women and 45 men observed one of three randomly assigned female faces (with eye size manipulation, and rated initial attraction and honesty. They were then asked to read an acquaintance rape scenario with a traditional woman, rating the victim and perpetrator responsibility. Eye size was shown to affect all the study variables: the female face with large eyes was seen as more attractive and honest, was held less responsible for her own victimization, and the offender was held more responsible. Gender was proven to affect perceived initial attraction and victim responsibility. Theoretical and práctical implications were discussed.

  1. Multi-agent Contracting and Reconfiguration in Competitive Environments using Acquaintance Models

    Directory of Open Access Journals (Sweden)

    J. Bíba

    2006-01-01

    Full Text Available Cooperation of agents in competitive environments is more complicated than in collaborative environments. Both replanning and reconfiguration play a crucial role in cooperation, and introduce a means for implementating a system flexibility. The concepts of commitments, decommitments with penalties and subcontracting may facilitate effective reconfiguration and replanning. Agents in competitive environments are fully autonomous and selfinterested. Therefore the setting of penalties and profit computation cannot be provided centrally. Both the costs and the gain differ from agent to agent with respect to contracts already agreed and resources load. This paper proposes an acquaintance model for contracting in competitive environments and introduces possibilities of reconfigurating in competitive environments as a means of decommitment optimization with respect to resources load and profit maximization. The presented algorithm for contract price setting does not use any centralized knowledge and provides results corresponding to a realistic environment. A simple customerprovider scenario proves this algorithm in competitive contracting. 

  2. Spatial Assimilation in Denmark?

    DEFF Research Database (Denmark)

    Andersen, Hans Skifter

    2010-01-01

    In most European countries ethnic minorities have had a tendency to settle in certain parts of cities, and often in social housing, together with other immigrants in so-called multiethnic neighbourhoods. An explanation for this could be low income combined with lack of knowledge of the housing...... market and discrimination, which limits the housing possibilities for ethnic minorities. Another explanation could be that immigrants for different reasons choose to settle in so-called ethnic enclaves where they can find an ethnic social network, which can support them in their new country. In...... traditional research literature about immigration it has been shown that for many immigrants living in enclaves has been a temporary situation. The 'spatial assimilation theory' says that this situation ends when the family has become more integrated in the new society and then moves to other parts of the...

  3. Nonlinear data assimilation

    CERN Document Server

    Van Leeuwen, Peter Jan; Reich, Sebastian

    2015-01-01

    This book contains two review articles on nonlinear data assimilation that deal with closely related topics but were written and can be read independently. Both contributions focus on so-called particle filters. The first contribution by Jan van Leeuwen focuses on the potential of proposal densities. It discusses the issues with present-day particle filters and explorers new ideas for proposal densities to solve them, converging to particle filters that work well in systems of any dimension, closing the contribution with a high-dimensional example. The second contribution by Cheng and Reich discusses a unified framework for ensemble-transform particle filters. This allows one to bridge successful ensemble Kalman filters with fully nonlinear particle filters, and allows a proper introduction of localization in particle filters, which has been lacking up to now.

  4. 76 FR 14115 - Culturally Significant Objects Imported for Exhibition Determinations: “Assorted Greek and Roman...

    Science.gov (United States)

    2011-03-15

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF STATE Culturally Significant Objects Imported for Exhibition Determinations: ``Assorted Greek and Roman Objects... Greek and Roman Objects'' imported from abroad for temporary exhibition within the United States, are...

  5. Actuality of assortment policy in the modern management of retail business enterprise

    Directory of Open Access Journals (Sweden)

    Yefimova Yevheniia

    2016-07-01

    Full Text Available In the result of research it has been found, that the assortment policy defines the course of actions for managing a point-of-sale assortment which foresees clarification and specification of strategic purpose and current tasks; development and grounding of facilities, methods and forms of activity for their achievement; determination of the real resources providing the realization of the plan. The constituents of assortment policy of enterprise of retail business are identified. It is well-proved that with the help of assortment policy achievement of ultimate goals of an enterprise is provided, the constituents of commercial strategy associate together and the possibility of the most effective usage of resources has arrived.

  6. Assortativity and leadership emergence from anti-preferential attachment in heterogeneous networks

    CERN Document Server

    Sendiña-Nadal, I; Wang, Z; Havlin, S; Boccaletti, S

    2015-01-01

    Many real-world networks exhibit degree-assortativity, with nodes of similar degree more likely to link to one another. Particularly in social networks, the contribution to the total assortativity varies with degree, featuring a distinctive peak slightly past the average degree. The way traditional models imprint assortativity on top of pre-defined topologies is via degree-preserving link permutations, which however destroy the particular graph's hierarchical traits of clustering. Here, we propose the first generative model which creates heterogeneous networks with scale-free-like properties and tunable realistic assortativity. In our approach, two distinct populations of nodes are added to an initial network seed: one (the followers) that abides by usual preferential rules, and one (the potential leaders) connecting via anti-preferential attachments, i.e. selecting lower degree nodes for their initial links. The latter nodes come to develop a higher average degree, and convert eventually into the final hubs....

  7. Understanding the Impact of Brand Delistings on Assortment Evaluations and Store Switching and Complaining Intentions

    NARCIS (Netherlands)

    L.M. Sloot (Laurens); P.C. Verhoef (Peter)

    2004-01-01

    textabstractRecently, retailers have begun considering which brands they can delist without reducing customer satisfaction, losing category sales, or increasing store switching behavior. Although several studies have considered assortment reductions, none has explicitly investigated the impact of to

  8. Recombination and assortment in the macronucleus of Tetrahymena thermophila: a theoretical study by computer simulation.

    Science.gov (United States)

    Doerder, F P; Diblasi, S L

    1984-12-01

    The compound nature of the macronucleus of Tetrahymena thermophila presents multiple opportunities for recombination between genes on the same macronuclear chromosome. Such recombinants should be detectable through their assortment at subsequent amitotic macronuclear divisions. Thus, a macronucleus that is initially AB/ab should produce recombinant assortees of the genotypes Ab/aB. Computer simulation shows that, when the recombination frequency is two or fewer times per cell cycle, recombinant assortees are produced at experimentally measurable frequencies of less than 40%. At higher recombination frequencies, linked genes appear to assort independently. The simulations also show that recombination during macronuclear development can be distinguished from recombination in subsequent cell cycles only if the first appearance of recombinant assortees is 100 or more fissions after conjugation. The use of macronuclear recombination and assortment as a means of mapping macronuclear genes is severely constrained by the large variances in assortment outcomes; with experimentally small sample sizes, such mapping is impossible.

  9. A mechanism for the evolution of altruism among nonkin: positive assortment through environmental feedback.

    Science.gov (United States)

    Pepper, John W; Smuts, Barbara B

    2002-08-01

    The evolution of altruism often requires genetic similarity among interactors. For structured populations in which a social trait affects all group members, this entails positive assortment, meaning that cooperators and noncooperators tend to be segregated into different groups. Several authors have claimed that mechanisms other than common descent can produce positive assortment, but this claim has not been generally accepted. Here, we describe one such mechanism. The process of "environmental feedback" requires only that the cooperative trait affects the quality of the local environment and that individuals are more likely to leave low-quality than high-quality environments. We illustrate this dynamic using an agent-based spatial model of feeding restraint. Depending on parameter settings, results included both positive assortment (required for the evolution of altruism) and negative assortment (required for the evolution of spite). The mechanism of environmental feedback appears to be a general one that could play a role in the evolution of many forms of cooperation.

  10. Educational assortative mating and economic inequality: a comparative analysis of three Latin American countries.

    Science.gov (United States)

    Torche, Florencia

    2010-05-01

    Educational assortative mating and economic inequality are likely to be endogenously determined, but very little research exists on their empirical association. Using census data and log-linear and log-multiplicative methods, I compare the patterns of educational assortative mating in Brazil, Chile, and Mexico, and explore the association between marital sorting and earnings inequality across countries. The analysis finds substantial variation in the strength of specific barriers to educational intermarriage between countries, and a close association between these barriers and the earnings gaps across educational categories within countries. This finding suggests an isomorphism between assortative mating and economic inequality. Furthermore, educational marital sorting is remarkably symmetric across gender in spite of the different resources that men and women bring to the union. This study highlights the limitations of using single aggregate measures of spousal educational resemblance (such as the correlation coefficient between spouses' schooling) to capture variation in assortative mating and its relationship with socioeconomic inequality.

  11. An institutional mechanism for assortment in an ecology of games.

    Science.gov (United States)

    Smaldino, Paul E; Lubell, Mark

    2011-01-01

    Recent research has revived Long's "ecology of games" model to analyze how social actors cooperate in the context of multiple political and social games. However, there is still a paucity of theoretical work that considers the mechanisms by which large-scale cooperation can be promoted in a dynamic institutional landscape, in which actors can join new games and leave old ones. This paper develops an agent-based model of an ecology of games where agents participate in multiple public goods games. In addition to contribution decisions, the agents can leave and join different games, and these processes are de-coupled. We show that the payoff for cooperation is greater than for defection when limits to the number of actors per game ("capacity constraints") structure the population in ways that allow cooperators to cluster, independent of any complex individual-level mechanisms such as reputation or punishment. Our model suggests that capacity constraints are one effective mechanism for producing positive assortment and increasing cooperation in an ecology of games. The results suggest an important trade-off between the inclusiveness of policy processes and cooperation: Fully inclusive policy processes reduce the chances of cooperation.

  12. Reconsidering the Heritability of Intelligence in Adulthood: Taking Assortative Mating and Cultural Transmission into Account

    OpenAIRE

    Vinkhuyzen, Anna A E; van der Sluis, Sophie; Maes, Hermine H. M.; Posthuma, Danielle

    2011-01-01

    Heritability estimates of general intelligence in adulthood generally range from 75 to 85%, with all heritability due to additive genetic influences, while genetic dominance and shared environmental factors are absent, or too small to be detected. These estimates are derived from studies based on the classical twin design and are based on the assumption of random mating. Yet, considerable positive assortative mating has been reported for general intelligence. Unmodeled assortative mating may ...

  13. Assortment structure in poplar plantation Populus x euramerjcana I-214 based on European standard

    Directory of Open Access Journals (Sweden)

    Danilović Milorad

    2005-01-01

    Full Text Available Assortment structure in poplar plantation Populus x euramericana I-214 was obtained by European standard for round wood. Based on the data of theoretical cutting, the correlation between total volume of assortments and tree diameter at breast height was established. Model of the function representing the relation between total volume of assortments of superior quality and tree diameter is reciprocal. The relation between total volumes of normal-quality assortments can be represented by a logarithm model of the function, and the relation between total volume of assortments which cannot be classified into any quality class and tree diameter is best represented by a degree model. Knots up to the height of 6 m had a significant effect on the percentage of classes of superior quality. If the lower branches were pruned from standing trees up to the height of 6 m, the percentage of this class would increase averagely by 22.07%. This shows that pruning of lower branches is a very significant plantation tending measure and that it should be performed in time. Sweep also caused the decrease of percentage of superior assortments, but not to the expected degree, because the plantation is situated along the river Sava.

  14. The relationship between intraspecific assortative mating and reproductive isolation between divergent populations

    Institute of Scientific and Technical Information of China (English)

    Daniel I.BOLNICK; Mark KIRKPATRICK

    2012-01-01

    The term'assortative mating' has been applied to describe two very different phenomena:(1) the tendency for individuals to choose phenotypically similar mates from among conspecifics; or (2) the tendency to prefer conspecific over heterospecific mates (behavioral reproductive isolation).Both forms of assortative mating are widespread in nature,but the relationship between these behaviors remains unclear.Namely,it is plausible that a preference for phenotypically similar conspecifics incidentally reduces the probability of mating with phenotypically divergent heterospecifics.We present a model to calculate how the level of reproductive isolation depends on intraspecific assortative mating and the phenotypic divergence between species.For empirically reasonable levels of intraspecific assortment on a single trait axis,we show that strong reproductive isolation requires very substantial phenotypic divergence.We illustrate this point by applying our model to empirical data from threespine stickleback Gasterosteus aculeatus and Darwin's Finches (Geospiza spp).We conclude that typical levels of intraspecific assortment cannot generally be extrapolated to explain levels of interspecitie reproductive isolation.Instead,reproductive isolation between species likely arises from different mate choice behaviors,or multivariate assortative mating.

  15. Linking intra- and interspecific assortative mating: Consequences for asymmetric sexual isolation.

    Science.gov (United States)

    Svensson, Erik I; Nordén, Anna; Waller, John T; Runemark, Anna

    2016-06-01

    Assortative mating is of interest because of its role in speciation and the maintenance of species boundaries. However, we know little about how within-species assortment is related to interspecific sexual isolation. Most previous studies of assortative mating have focused on a single trait in males and females, rather than utilizing multivariate trait information. Here, we investigate how intraspecific assortative mating relates to sexual isolation in two sympatric and congeneric damselfly species (genus Calopteryx). We connect intraspecific assortment to interspecific sexual isolation by combining field observations, mate preference experiments, and enforced copulation experiments. Using canonical correlation analysis, we demonstrate multivariate intraspecific assortment for body size and body shape. Males of the smaller species mate more frequently with heterospecific females than males of the larger species, which showed less attraction to small heterospecific females. Field experiments suggest that sexual isolation asymmetry is caused by male preferences for large heterospecific females, rather than by mechanical isolation due to interspecific size differences or female preferences for large males. Male preferences for large females and male-male competition for high quality females can therefore counteract sexual isolation. This sexual isolation asymmetry indicates that sexual selection currently opposes a species boundary. PMID:27151764

  16. Linking intra- and interspecific assortative mating: Consequences for asymmetric sexual isolation.

    Science.gov (United States)

    Svensson, Erik I; Nordén, Anna; Waller, John T; Runemark, Anna

    2016-06-01

    Assortative mating is of interest because of its role in speciation and the maintenance of species boundaries. However, we know little about how within-species assortment is related to interspecific sexual isolation. Most previous studies of assortative mating have focused on a single trait in males and females, rather than utilizing multivariate trait information. Here, we investigate how intraspecific assortative mating relates to sexual isolation in two sympatric and congeneric damselfly species (genus Calopteryx). We connect intraspecific assortment to interspecific sexual isolation by combining field observations, mate preference experiments, and enforced copulation experiments. Using canonical correlation analysis, we demonstrate multivariate intraspecific assortment for body size and body shape. Males of the smaller species mate more frequently with heterospecific females than males of the larger species, which showed less attraction to small heterospecific females. Field experiments suggest that sexual isolation asymmetry is caused by male preferences for large heterospecific females, rather than by mechanical isolation due to interspecific size differences or female preferences for large males. Male preferences for large females and male-male competition for high quality females can therefore counteract sexual isolation. This sexual isolation asymmetry indicates that sexual selection currently opposes a species boundary.

  17. Assessing the Impact of Acquaintance Rape: Interviews with Women Who Are Victims/Survivors of Sexual Assault while in College

    Science.gov (United States)

    Guerette, Sarah M.; Caron, Sandra L.

    2007-01-01

    This is a study consisting of in-depth interviews with 12 women who were victims/survivors of acquaintance rape while attending a university in the Northeast. The interviews focused on research questions concerning actions taken by the victim/survivor after the assault, reactions to her disclosure of the assault, and the impact of assault. It was…

  18. Gender, Gender Identity, Rape Myth Acceptance, and Time of Initial Resistance on the Perception of Acquaintance Rape Blame and Avoidability.

    Science.gov (United States)

    Kopper, Beverly A.

    1996-01-01

    Investigated the role of gender, gender role identity, rape myth acceptance, and initial resistance in assigning blame in the case of acquaintance rape, and studied the perceived avoidability of the assault for 355 female and 179 male college students. The gender differences in responses are discussed. (SLD)

  19. Beyond "No Means No." Outcomes of an Intensive Program to Train Peer Facilitators for Campus Acquaintance Rape Education.

    Science.gov (United States)

    Lonsway, Kimberly A.; Klaw, Elena L.; Berg, Dianne R.; Waldo, Craig R.; Kothari, Chevon; Mazurek, Christopher J.; Hegeman, Kurt E.

    1998-01-01

    Examines the effects of a university course designed to train peer facilitators to conduct rape education workshops, Campus Acquaintance Rape Education (CARE). Participants (N=74) experienced comprehensive attitude change; both men and women participants became more willing and able to directly express themselves and assert their needs in ways…

  20. Date and Acquaintance Rape: The Legal Point of View. Part 2. Reform of Rape Laws and Alternatives to Criminal Prosecution.

    Science.gov (United States)

    Julian, Frank H.

    1993-01-01

    Second article in two-part series on date and acquaintance rape examines modern reforms in rape laws and alternatives to criminal prosecution. Explains the Rape Shield Law, designed to prevent victim's sexual history from being used against her to prove promiscuity, tendency to lie, or low moral character. Other common statutory revisions are…

  1. Beyond No Means No: Outcomes of an Intensive Program To Train Peer Facilitators for Campus Acquaintance Rape Education.

    Science.gov (United States)

    Lonsway, Kimberly A.; Klaw, Elena L.; Berg, Dianne R.; Waldo, Craig R.; Kothari, Chevon; Mazurek, Christopher J.; Hegeman, Kurt E.

    As part of a larger multimethod evaluation, the present study examined the effects of a uniquely intensive rape education program. Participants included 74 undergraduates (53 women and 21 men) enrolled in Campus Acquaintance Rape Education (CARE), a semester-long university course designed to train peer facilitators to conduct rape education…

  2. Data assimilation in hydrological modelling

    DEFF Research Database (Denmark)

    Drecourt, Jean-Philippe

    Data assimilation is an invaluable tool in hydrological modelling as it allows to efficiently combine scarce data with a numerical model to obtain improved model predictions. In addition, data assimilation also provides an uncertainty analysis of the predictions made by the hydrological model...... with model non-linearities and biased errors. A literature review analyzes the most popular techniques and their application in hydrological modelling. Since bias is an important problem in groundwater modelling, two bias aware Kalman filters have been implemented and compared using an artificial test case....... In this thesis, the Kalman filter is used for data assimilation with a focus on groundwater modelling. However the developed techniques are general and can be applied also in other modelling domains. Modelling involves conceptualization of the processes of Nature. Data assimilation provides a way to deal...

  3. Global Land Data Assimilation System

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — The goal of the Global Land Data Assimilation System (GLDAS) is to ingest satellite- and ground-based observational data products, using advanced land surface...

  4. Global Data Assimilation System (GDAS)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The Global Data Assimilation System (GDAS) is the system used by the Global Forecast System (GFS) model to place observations into a gridded model space for the...

  5. WAVE ASSIMILATION AND NUMERICAL PREDICTION

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    An adjoint variational method for wave data assimilation in the LAGFD-WAM wave model is proposed. The adjoint equation of the wavenumber energy spectrum balance equation is derived. And fortunately, its characteristic equations are the same as those in the LAGFD-WAM wave model. Simple experiments on the functional optimization and assimilation effectiveness during the prediction period indicated that the adjoint variational method is effective for wave assimilation and that the initial optimization of the wave model is important for the short-range wave prediction. All of this is under the assumption that the wind field is accurate, the method is the important first step for combined wind and wave data assimilation systems.

  6. Genome assortment, not serogroup, defines Vibrio cholerae pandemic strains

    Energy Technology Data Exchange (ETDEWEB)

    Brettin, Thomas S [Los Alamos National Laboratory; Bruce, David C [Los Alamos National Laboratory; Challacombe, Jean F [Los Alamos National Laboratory; Detter, John C [Los Alamos National Laboratory; Han, Cliff S [Los Alamos National Laboratory; Munik, A C [Los Alamos National Laboratory; Chertkov, Olga [Los Alamos National Laboratory; Meincke, Linda [Los Alamos National Laboratory; Saunders, Elizabeth [Los Alamos National Laboratory; Choi, Seon Y [SEOUL NATL. UNIV.; Haley, Bradd J [U. MARYLAND; Taviani, Elisa [U. MARYLAND; Jeon, Yoon - Seong [INTL. VACCINE INST. SEOUL; Kim, Dong Wook [INTL. VACCINE INST. SEOUL; Lee, Jae - Hak [SEOUL NATL. UNIV.; Walters, Ronald A [PNNL; Hug, Anwar [NATL. INST. CHOLERIC ENTERIC DIS.; Colwell, Rita R [U. MARYLAND

    2009-01-01

    Vibrio cholerae, the causative agent of cholera, is a bacterium autochthonous to the aquatic environment, and a serious public health threat. V. cholerae serogroup O1 is responsible for the previous two cholera pandemics, in which classical and El Tor biotypes were dominant in the 6th and the current 7th pandemics, respectively. Cholera researchers continually face newly emerging and re-emerging pathogenic clones carrying combinations of new serogroups as well as of phenotypic and genotypic properties. These genotype and phenotype changes have hampered control of the disease. Here we compare the complete genome sequences of 23 strains of V. cholerae isolated from a variety of sources and geographical locations over the past 98 years in an effort to elucidate the evolutionary mechanisms governing genetic diversity and genesis of new pathogenic clones. The genome-based phylogeny revealed 12 distinct V. cholerae phyletic lineages, of which one, designated the V. cholerae core genome (CG), comprises both O1 classical and EI Tor biotypes. All 7th pandemic clones share nearly identical gene content, i.e., the same genome backbone. The transition from 6th to 7th pandemic strains is defined here as a 'shift' between pathogenic clones belonging to the same O1 serogroup, but from significantly different phyletic lineages within the CG clade. In contrast, transition among clones during the present 7th pandemic period can be characterized as a 'drift' between clones, differentiated mainly by varying composition of laterally transferred genomic islands, resulting in emergence of variants, exemplified by V.cholerae serogroup O139 and V.cholerae O1 El Tor hybrid clones that produce cholera toxin of classical biotype. Based on the comprehensive comparative genomics presented in this study it is concluded that V. cholerae undergoes extensive genetic recombination via lateral gene transfer, and, therefore, genome assortment, not serogroup, should be used to

  7. Instant RubyMine assimilation

    CERN Document Server

    Jones, Dave

    2013-01-01

    Filled with practical, step-by-step instructions and clear explanations for the most important and useful tasks. Get the job done and learn as you go. A practical guide comprising of easy-to-follow recipes which provide concise and clear steps to help you enter the world of RubyMine.Instant RubyMine is ideal for you, if you are new to RubyMine or well acquainted with the technology. All you need is basic knowledge of writing in Ruby or Ruby on Rails.

  8. Ethnic goods and immigrant assimilation

    OpenAIRE

    Abdulloev, Ilhom; Epstein, Gil S.; Ira N. Gang

    2014-01-01

    Some immigrants try to keep their ethnicity hidden while others become ever deeply more mired in their home culture. We argue that among immigrants this struggle manifests itself in the ethnic goods they choose to consume. Different types of ethnic goods have vastly different effects on immigrant assimilation. We develop a simple theoretical model useful for capturing the consequences of this struggle, illustrating it with examples of Central Asian assimilation into the Muscovite economy.

  9. Data Assimilation Applications in Hydrology

    OpenAIRE

    Deliu, Ciprian; Giurma, Ion

    2014-01-01

    In this paper we review some data assimilation applications in hydrology and we investigate the benefits of applying the ensemble Kalman filter methods on a specific hydrodynamic model of a river network using the MIKE 11 software. We explore the efects of assimilating measurements from different locations (generated by a reference model) into a model forced with erroneous boundary conditions and also examine the effect of using coloured noise for describing uncertainty in the upstream bounda...

  10. Assortative social learning and its implications for human (and animal?) societies.

    Science.gov (United States)

    Katsnelson, Edith; Lotem, Arnon; Feldman, Marcus W

    2014-07-01

    Choosing from whom to learn is an important element of social learning. It affects learner success and the profile of behaviors in the population. Because individuals often differ in their traits and capabilities, their benefits from different behaviors may also vary. Homophily, or assortment, the tendency of individuals to interact with other individuals with similar traits, is known to affect the spread of behaviors in humans. We introduce models to study the evolution of assortative social learning (ASL), where assorting on a trait acts as an individual-specific mechanism for filtering relevant models from which to learn when that trait varies. We show that when the trait is polymorphic, ASL may maintain a stable behavioral polymorphism within a population (independently of coexistence with individual learning in a population). We explore the evolution of ASL when assortment is based on a nonheritable or partially heritable trait, and when ASL competes with different non-ASL strategies: oblique (learning from the parental generation) and vertical (learning from the parent). We suggest that the tendency to assort may be advantageous in the context of social learning, and that ASL might be an important concept for the evolutionary theory of social learning.

  11. 'Prudent habitat choice': a novel mechanism of size-assortative mating.

    Science.gov (United States)

    Taborsky, B; Guyer, L; Demus, P

    2014-06-01

    Assortative mating, an ubiquitous form of nonrandom mating, strongly impacts Darwinian fitness and can drive biological diversification. Despite its ecological and evolutionary importance, the behavioural processes underlying assortative mating are often unknown, and in particular, mechanisms not involving mate choice have been largely ignored so far. Here, we propose that assortative mating can arise from 'prudent habitat choice', a general mechanism that acts under natural selection, and that it can occur despite a complete mixing of phenotypes. We show that in the cichlid Eretmodus cyanostictus size-assortative mating ensues, because individuals of weaker competitive ability ignore high-quality but strongly competed habitat patches. Previous studies showed that in E. cyanostictus, size-based mate preferences are absent. By field and laboratory experiments, here we showed that (i) habitat quality and body size are correlated in this species; (ii) territories with more stone cover are preferred by both sexes in the absence of competition; and (iii) smaller fish prudently occupy vacant territories of worse quality than do larger fish. Prudent habitat choice is likely to be a widespread mechanism of assortative mating, as both preferences for and dominance-based access to high-quality habitats are generic phenomena in animals.

  12. Phenotypic assortment in wild primate networks: implications for the dissemination of information.

    Science.gov (United States)

    Carter, Alecia J; Lee, Alexander E G; Marshall, Harry H; Ticó, Miquel Torrents; Cowlishaw, Guy

    2015-05-01

    Individuals' access to social information can depend on their social network. Homophily-a preference to associate with similar phenotypes-may cause assortment within social networks that could preclude information transfer from individuals who generate information to those who would benefit from acquiring it. Thus, understanding phenotypic assortment may lead to a greater understanding of the factors that could limit the transfer of information between individuals. We tested whether there was assortment in wild baboon (Papio ursinus) networks, using data collected from two troops over 6 years for six phenotypic traits-boldness, age, dominance rank, sex and the propensity to generate/exploit information-using two methods for defining a connection between individuals-time spent in proximity and grooming. Our analysis indicated that assortment was more common in grooming than proximity networks. In general, there was homophily for boldness, age, rank and the propensity to both generate and exploit information, but heterophily for sex. However, there was considerable variability both between troops and years. The patterns of homophily we observed for these phenotypes may impede information transfer between them. However, the inconsistency in the strength of assortment between troops and years suggests that the limitations to information flow may be quite variable.

  13. METHODOLOGY OF KNOWLEDGE RESOURCES AUDIT FOR FORMATION OF PHARMACY ORGANIZATION ASSORTMENT

    Directory of Open Access Journals (Sweden)

    I. M. Razdorskaya

    2015-01-01

    Full Text Available The timeliness of this subject is conditioned by the increase of a role of knowledge in pharmacy organizations (PO management, significance increase of non-material assets in a competition on the pharmaceutical market. The development and substantiation of methodology of knowledge resources audit significance on the example of drug assortment formation for allergic rhinitis treatment. We have used sociological, statistic, expert methods of a study. Close attention was paid to the method of target management, construction of target tree. The construction of the target tree of the knowledge resources audit was based on the main target establishment, targets of the first level, and eight subtargets. We have offered new special positions of assortment formation. “Formation of consumers’ loyalty” is the target of the first level, subtargets “Analysis of clients preferences”, “Transformation of clients preferences”, “Positioning of consumers by the compliance degree”. We have determined the relevance significance by the main target achievement – rational assortment formation. We have shown that the achievement of the first level target “Formation of consumers’  loyalty” conduce the achievement of the main target by 40%. The analysis of the current assortment and a process of assortment upgrading guarantee the achievement of the target by 30% each. The methodology is prospective for knowledge resources audit by the principal business processes of pharmacy organizations.  

  14. Using Social Network Methods to Test for Assortment of Prosociality among Korean High School Students.

    Science.gov (United States)

    Kim, Jun-Hong; Holman, Darryl J; Goodreau, Steven M

    2015-01-01

    Assortative interaction among altruistic individuals is a necessary condition for the evolution of cooperation. The requirement for assortment holds regardless of whether a meta-population is subdivided into distinct and isolated subgroups or has ephemeral boundaries with a high migration rate. The assumption, however, is rarely tested directly. In this paper, we develop a method to test for assortment of prosociality in network-structured data. The method is applied to a friendship network collected from 238 Korean students attending the same high school. A mixing matrix was used to explore the presence of assortative friendship among more prosocial individuals. An exponential random graph model of network structure that accounts for additional observed relational propensities (higher-than-expected number of people nominating no friends) and sampling constraints (upper bound on friendship nominations) found that individual prosociality predicted friendship propensity, and that individuals with higher prosocial scores had a higher probability of befriending other more prosocial individuals. The results reveal that a considerable level of assortment of prosociality characterizes this population.

  15. Comparison of different assimilation schemes in a sequential Kalman filter assimilation system

    OpenAIRE

    Yan, Yajing; Barth, Alexander; Beckers, Jean-Marie

    2014-01-01

    In this paper, four assimilation schemes, including an intermittent assimilation scheme (INT) and three incremental assimilation schemes (IAU 0, IAU 50 and IAU 100), are compared in the same assimilation experiments with a nonlinear ocean circulation model using the Ensemble Kalman Filter as assimilation method. The three IAU schemes differ from each other in the position of the increment update window that has the same size as the assimilation window. 0, 50 and 100 correspond to the degree o...

  16. Effective Assimilation of Global Precipitation

    Science.gov (United States)

    Lien, G.; Kalnay, E.; Miyoshi, T.; Huffman, G. J.

    2012-12-01

    Assimilating precipitation observations by modifying the moisture and sometimes temperature profiles has been shown successful in forcing the model precipitation to be close to the observed precipitation, but only while the assimilation is taking place. After the forecast start, the model tends to "forget" the assimilation changes and lose their extra skill after few forecast hours. This suggests that this approach is not an efficient way to modify the potential vorticity field, since this is the variable that the model would remember. In this study, the ensemble Kalman filter (EnKF) method is used to effectively change the potential vorticity field by allowing ensemble members with better precipitation to receive higher weights. In addition to using an EnKF, two other changes in the precipitation assimilation process are proposed to solve the problems related to the highly non-Gaussian nature of the precipitation variable: a) transform precipitation into a Gaussian distribution based on its climatological distribution, and b) only assimilate precipitation at the location where some ensemble members have positive precipitation. The idea is first tested by the observing system simulation experiments (OSSEs) using SPEEDY, a simplified but realistic general circulation model. When the global precipitation is assimilated in addition to conventional rawinsonde observations, both the analyses and the medium range forecasts are significantly improved as compared to only having rawinsonde observations. The improvement is much reduced when only modifying the moisture field with the same approach, which shows the importance of the error covariance between precipitation and all other model variables. The effect of precipitation assimilation is larger in the Southern Hemisphere than that in the Northern Hemisphere because the Northern Hemisphere analyses are already accurate as a result of denser rawinsonde stations. Assimilation of precipitation using a more comprehensive

  17. Fear of acquaintance versus stranger rape as a "master status": towards refinement of the "shadow of sexual assault".

    Science.gov (United States)

    Wilcox, Pamela; Jordan, Carol E; Pritchard, Adam J

    2006-06-01

    Using a sample of 1010 women from a southeastern state university, we explore whether associations between fear of sexual assault and other crime-specific fears vary based on presumed victim-offender relationship. More specifically, we assess the extent to which fear of stranger- and acquaintance-perpetrated sexual assaults differ in the extent to which they are correlated with fear of other crime victimizations. Multivariate logistic regression analysis revealed that both fear of stranger-perpetrated sexual assault and fear of acquaintance-perpetrated sexual assault were positively associated with nearly all other crime-specific fears under examination. However, associations were particularly strong between fear of sexual assault by a stranger and fear of other stranger-perpetrated crimes. Findings have significant implications for how academic institutions should comprehensively address direct and indirect negative influences of violence against college women. PMID:16761859

  18. The gendered embodiment of shame: Intersections of acquaintance rape, trauma and self-blame in Pompidou posse by Sarah Lotz

    OpenAIRE

    Jessica Murray

    2014-01-01

    This article offers a feminist literary analysis of the gendered embodiment of shame in Pompidou posse by Sarah Lotz. In this novel, Lotz depicts female characters who are sexually assaulted by acquaintances and the resultant shame and trauma reside in their bodies. I will demonstrate that the embodied shame of these characters is distinctly gendered and that this shapes their attempts to cope with the aftermath of the sexual assaults. A close reading of the text reveals that the characters a...

  19. Women's Preference for a Male Acquaintance Enhances Social Reward Processing of Material Goods in the Anterior Cingulate Cortex.

    Directory of Open Access Journals (Sweden)

    Jun Nakagawa

    Full Text Available Men, like the male of many animal species, use gifts to build satisfactory relationships with a desired woman. From the woman's perspective, all gifts are not always equally rewarding; the reward value of a gift depends on two factors: (1 the giver and (2 the type of the gift (the gift's social meaning. In this study, we investigated how these two factors interactively determine the reward value of a gift. Specifically, we examined how the neural processing for understanding a gift's social meaning is modulated by preferences for the giver. We performed a functional magnetic resonance imaging (fMRI study in which a female participant was asked to judge a gift from a male she was acquainted with in real life. We examined the interactive effects between (1 the female participant's attitude toward the male acquaintance (liked vs. uninteresting and (2 the type of the gift (romantic [e.g., bouquet, earrings, and perfumes] vs. non-romantic [e.g., pencils, memo pad, and moneybox]. We found that preference for an acquaintance selectively modulated activity in the anterior cingulate cortex (ACC in response to romantic gifts, compared to non-romantic gifts. In contrast, if the woman was indifferent toward an acquaintance, no activity modulation was observed in this area for the same gifts. In addition, the ACC showed functional connectivity with the supplementary motor area/dorsal ACC (SMA/dACC, an area within the dorsal mediofrontal cortex, suggesting that it integrates action monitoring and emotional and cognitive processing in decision-making. These results suggest that attitude toward an opposite sex member has a modulatory role in recognizing the social meaning of material goods--preference for the member is a powerful modulator of social reward processing.

  20. Robustness and assortativity for diffusion-like processes in scale-free networks

    Science.gov (United States)

    D'Agostino, G.; Scala, A.; Zlatić, V.; Caldarelli, G.

    2012-03-01

    By analysing the diffusive dynamics of epidemics and of distress in complex networks, we study the effect of the assortativity on the robustness of the networks. We first determine by spectral analysis the thresholds above which epidemics/failures can spread; we then calculate the slowest diffusional times. Our results shows that disassortative networks exhibit a higher epidemiological threshold and are therefore easier to immunize, while in assortative networks there is a longer time for intervention before epidemic/failure spreads. Moreover, we study by computer simulations the sandpile cascade model, a diffusive model of distress propagation (financial contagion). We show that, while assortative networks are more prone to the propagation of epidemic/failures, degree-targeted immunization policies increases their resilience to systemic risk.

  1. THE IMPROVING OF ASSORTMENT BY «BUMFA GROUP» IN CHERKESSK

    Directory of Open Access Journals (Sweden)

    Gayduk V. I.

    2015-09-01

    Full Text Available The article presents and analyzes the assortment of "Bumfa Group" with the methods of ABC analysis, XYZ-analysis. It gives the description of the goods offered by the organization, its customers and its main competitors. The profile of competitive advantages and disadvantages is compiled. It presents the results of marketing research of consumers acquiring products offered by LLC "Bumfa Group" - the goods in terms of popularity, the factors influencing the decision to purchase, customers’ satisfaction in price, packaging and product quality, the results of customers’choice of new products to update the assortment, customers’ satisfaction in volume of incoming advertising information about the products of "Bumfa Group." The necessity to optimize the assortment of the organization is founded. To achieve this aim we developed a project to introduce new products in the range of goods - wet wipes for office equipment. The characteristics of the new product, the production plan and performance indicators of the project are supplied

  2. Manufacturer and retailer brands in food retail assortments: Notes from a shopping trip across Europe

    DEFF Research Database (Denmark)

    Esbjerg, Lars; Grunert, Klaus G.; Bech-Larsen, Tino;

    retailer branded products in an attempt to differentiate themselves by offering goods only available in their stores. Despite the importance of branding to retailers, the branding literature has focused on how manufacturers develop and maintain strong brands. Relatively little work has been done...... food retailers focus on whether they offer the "right" assort-ment to consumers. Under headings such as efficient consumer response (ECR) and cate-gory management (CM), retailers have been readjusting their assortments, delisting many brands that were deemed to be under-performing and including...... of 'retailer brand archi-tecture', we use this concept to investigate the brand architecture of a number of European food retailers in order to determine similarities and differences in brand architecture strategies. The paper is structured as follows: firstly, the concept of brand archi-tecture is presented...

  3. Geographically selective assortment of cycles in pandemics: meta-analysis of data collected by Chizhevsky.

    Science.gov (United States)

    Gumarova, L; Cornélissen, G; Hillman, D; Halberg, F

    2013-10-01

    In the incidence patterns of cholera, diphtheria and croup during the past when they were of epidemic proportions, we document a set of cycles (periods), one of which was reported and discussed by A. L. Chizhevsky in the same data with emphasis on the mirroring in human disease of the ~11-year sunspot cycle. The data in this study are based on Chizhevsky’s book The Terrestrial Echo of Solar Storms and on records from the World Health Organization. For meta-analysis, we used the extended linear and nonlinear cosinor. We found a geographically selective assortment of various cycles characterizing the epidemiology of infections, which is the documented novel topic of this paper, complementing the earlier finding in the 21st century or shortly before, of a geographically selective assortment of cycles characterizing human sudden cardiac death. Solar effects, if any, interact with geophysical processes in contributing to this assortment.

  4. The cultural context of nondisclosure of alcohol-involved acquaintance rape among Asian American college women: a qualitative study.

    Science.gov (United States)

    Koo, Kelly H; Nguyen, Hong V; Andrasik, Michele P; George, William H

    2015-01-01

    With high college enrollment and increasing alcohol use, Asian American (AA) college women may be at particular risk for experiencing alcohol-involved acquaintance rape. Although AA women have expressed the weakest intentions to report rape when compared to other ethnic groups, cultural factors influencing these intentions remain unexamined. Guided by grounded theory, 17 self-identified AA college women were interviewed about how the average AA college woman would respond to an alcohol-involved acquaintance rape. Despite awareness of benefits of disclosing rape, participants emphasized that nondisclosure would be the normative response. Three themes emerged from participants: institutional, sociocultural, and psychological contexts of nondisclosure. At an institutional level, nondisclosure referenced mental health and police services, which included Asian stereotypes and mistrust of police. Within a sociocultural context, rape nondisclosure focused on negative consequences on relationships with parents and, to a lesser extent, on friendships. Emotional avoidance and not labeling an acquaintance rape as rape were psychological strategies for rape nondisclosure. Participant's conceptualizations of mental and physical health concerns, specifically post-rape concerns, were framed within sociocultural/macrostructural contexts and may not match that of the more individualistic U.S. mainstream conceptualizations of health. Culturally sensitive rape education may be more effective in increasing rape prevention and support. PMID:24215167

  5. Co-assortment in integron-associated gene cassette assemblages in environmental DNA samples

    Directory of Open Access Journals (Sweden)

    Michael Carolyn A

    2010-08-01

    Full Text Available Abstract Background It has been shown that integron-associated gene cassettes exist largely in tandem arrays of variable size, ranging from antibiotic resistance arrays of three to five cassettes up to arrays of more than 100 cassettes associated with the vibrios. Further, the ecology of the integron/gene cassette system has been investigated by showing that very many different cassettes are present in even small environmental samples. In this study, we seek to extend the ecological perspective on the integron/gene cassette system by investigating the way in which this diverse cassette metagenome is apportioned amongst prokaryote lineages in a natural environment. Results We used a combination of PCR-based techniques applied to environmental DNA samples and ecological analytical techniques to establish co-assortment within cassette populations, then establishing the relationship between this co-assortment and genomic structures. We then assessed the distribution of gene cassettes within the environment and found that the majority of gene cassettes existed in large co-assorting groups. Conclusions Our results suggested that the gene cassette diversity of a relatively pristine sampling environment was structured into co-assorting groups, predominantly containing large numbers of cassettes per group. These co-assorting groups consisted of different gene cassettes in stoichiometric relationship. Conservatively, we then attributed co-assorting cassettes to the gene cassette complements of single prokaryote lineages and by implication, to large integron-associated arrays. The prevalence of large arrays in the environment raises new questions about the assembly, maintenance and utility of large cassette arrays in prokaryote populations.

  6. Storm surge variational assimilation model

    Directory of Open Access Journals (Sweden)

    Shi-li HUANG

    2010-06-01

    Full Text Available To eliminate errors caused by uncertainty of parameters and further improve capability of storm surge forecasting, the variational data assimilation method is applied to the storm surge model based on unstructured grid with high spatial resolution. The method can effectively improve the forecasting accuracy of storm surge induced by typhoon through controlling wind drag force coefficient parameter. The model is first theoretically validated with synthetic data. Then, the real storm surge process induced by the TC 0515 typhoon is forecasted by the variational data assimilation model, and results show the feasibility of practical application.

  7. From sparse to dense and from assortative to disassortative in online social networks

    CERN Document Server

    Li, Menghui; Gong, Xiaofeng; Li, Kun; Wu, Jinshan; Di, Zengru; Lai, Choy-Heng

    2013-01-01

    In this paper, inspired by the analysis on several empirical online social networks, we propose a simple reaction-diffusion-like coevolving model, in which individuals are activated to create links based on their states influenced by local dynamics and their own intension. It is shown that the model can reproduce the remarkable properties observed in empirical online social networks, particularly, that the assortative coefficients are neural or negative and the power law exponents are smaller than 2. Moreover, we demonstrate that, under feasible conditions, the modeling networks naturally convert from assortative to disassortative, and from sparse to dense. Our model is helpful for understanding the formation and evolution of online social networks.

  8. Effect of assortative mixing in the second-order Kuramoto model

    CERN Document Server

    Peron, Thomas K DM; Rodrigues, Francisco A; Kurths, Jürgen

    2015-01-01

    In this paper we analyze the second-order Kuramoto model presenting a positive correlation between the heterogeneity of the connections and the natural frequencies in scale-free networks. We numerically show that discontinuous transitions emerge not just in disassortative but also in assortative networks, in contrast with the first-order model. We also find that the effect of assortativity on network synchronization can be compensated by adjusting the phase damping. Our results show that it is possible to control collective behavior of damped Kuramoto oscillators by tuning the network structure or by adjusting the dissipation related to the phases movement.

  9. Female preference for male color is necessary and sufficient for assortative mating in 2 cichlid sister species

    NARCIS (Netherlands)

    Selz, Oliver M.; Pierotti, Michele E. R.; Maan, Martine E.; Schmid, Corinne; Seehausen, Ole

    2014-01-01

    A critical step for speciation in the face of gene flow is the origination of reproductive isolation. The evolution of assortative mating greatly facilitates this process. Assortative mating can be mediated by one or multiple cues across an array of sensory modalities. We here explore possible cues

  10. Data assimilation techniques in modeling ocean processes

    Digital Repository Service at National Institute of Oceanography (India)

    Mahadevan, R.; Fernandes, A.A.; Naqvi, S.W.A.

    control theory method are discussed. Application of data assimilation technique to physical problems governed by linear and nonlinear ordinary differential equations are explained. The formulation of data assimilation technique in one-dimensional models...

  11. Data assimilation the ensemble Kalman filter

    CERN Document Server

    Evensen, Geir

    2006-01-01

    Covers data assimilation and inverse methods, including both traditional state estimation and parameter estimation. This text and reference focuses on various popular data assimilation methods, such as weak and strong constraint variational methods and ensemble filters and smoothers.

  12. The Phonological Assimilation of Borrowing.

    Science.gov (United States)

    Suleiman, Saleh M.

    Linguistic borrowing from English to Jordanian Arabic at the lexical level is described, focusing on phonology and the extent to which Jordanian Arabic has affected the phonetic structure of English loans assimilated partially or completely into it. Conspicuous distinctive sound features in the two languages that may affect non-native speakers'…

  13. Data assimilation in reservoir management

    NARCIS (Netherlands)

    Rommelse, J.R.

    2009-01-01

    The research presented in this thesis aims at improving computer models that allow simulations of water, oil and gas flows in subsurface petroleum reservoirs. This is done by integrating, or assimilating, measurements into physics-bases models. In recent years petroleum technology has developed rapi

  14. Acquaintance ratings of the Big Five personality traits: incremental validity beyond and interactive effects with self-reports in the prediction of workplace deviance.

    Science.gov (United States)

    Kluemper, Donald H; McLarty, Benjamin D; Bing, Mark N

    2015-01-01

    It is widely established that the Big Five personality traits of conscientiousness, agreeableness, and emotional stability are antecedents to workplace deviance (Berry, Ones, & Sackett, 2007). However, these meta-analytic findings are based on self-reported personality traits. A recent meta-analysis by Oh, Wang, and Mount (2011) identified the value of acquaintance-reported personality in the prediction of job performance. The current investigation extends prior work by comparing the validities of self- and acquaintance-reported personality in the prediction of workplace deviance across 2 studies. We also hypothesized and tested an interactive, value-added integration of self- with acquaintance-reported personality using socioanalytic personality theory (R. T. Hogan, 1991). Both studies assessed self- and acquaintance-rated Big Five traits, along with supervisor-rated workplace deviance. However, the studies varied the measures of workplace deviance, and the 2nd study also included a self-rated workplace deviance criterion for additional comparison. Across both studies, the traits of conscientiousness and agreeableness were strong predictors of workplace deviance, and acquaintance-reported personality provided incremental validity beyond self-reports. Additionally, acquaintance-reported conscientiousness and agreeableness moderated the prediction of workplace deviance by interacting with the corresponding self-reported traits. Implications for personality theory and measurement are discussed along with applications for practice.

  15. Assortativity and leadership emerge from anti-preferential attachment in heterogeneous networks

    Science.gov (United States)

    Sendiña-Nadal, I.; Danziger, M. M.; Wang, Z.; Havlin, S.; Boccaletti, S.

    2016-02-01

    Real-world networks have distinct topologies, with marked deviations from purely random networks. Many of them exhibit degree-assortativity, with nodes of similar degree more likely to link to one another. Though microscopic mechanisms have been suggested for the emergence of other topological features, assortativity has proven elusive. Assortativity can be artificially implanted in a network via degree-preserving link permutations, however this destroys the graph’s hierarchical clustering and does not correspond to any microscopic mechanism. Here, we propose the first generative model which creates heterogeneous networks with scale-free-like properties in degree and clustering distributions and tunable realistic assortativity. Two distinct populations of nodes are incrementally added to an initial network by selecting a subgraph to connect to at random. One population (the followers) follows preferential attachment, while the other population (the potential leaders) connects via anti-preferential attachment: they link to lower degree nodes when added to the network. By selecting the lower degree nodes, the potential leader nodes maintain high visibility during the growth process, eventually growing into hubs. The evolution of links in Facebook empirically validates the connection between the initial anti-preferential attachment and long term high degree. In this way, our work sheds new light on the structure and evolution of social networks.

  16. The genetic correlation between height and IQ: shared genes or assortative mating?

    Directory of Open Access Journals (Sweden)

    Matthew C Keller

    2013-04-01

    Full Text Available Traits that are attractive to the opposite sex are often positively correlated when scaled such that scores increase with attractiveness, and this correlation typically has a genetic component. Such traits can be genetically correlated due to genes that affect both traits ("pleiotropy" and/or because assortative mating causes statistical correlations to develop between selected alleles across the traits ("gametic phase disequilibrium". In this study, we modeled the covariation between monozygotic and dizygotic twins, their siblings, and their parents (total N = 7,905 to elucidate the nature of the correlation between two potentially sexually selected traits in humans: height and IQ. Unlike previous designs used to investigate the nature of the height-IQ correlation, the present design accounts for the effects of assortative mating and provides much less biased estimates of additive genetic, non-additive genetic, and shared environmental influences. Both traits were highly heritable, although there was greater evidence for non-additive genetic effects in males. After accounting for assortative mating, the correlation between height and IQ was found to be almost entirely genetic in nature. Model fits indicate that both pleiotropy and assortative mating contribute significantly and about equally to this genetic correlation.

  17. The Genetic Correlation between Height and IQ: Shared Genes or Assortative Mating?

    Science.gov (United States)

    Keller, Matthew C.; Garver-Apgar, Christine E.; Wright, Margaret J.; Martin, Nicholas G.; Corley, Robin P.; Stallings, Michael C.; Hewitt, John K.; Zietsch, Brendan P.

    2013-01-01

    Traits that are attractive to the opposite sex are often positively correlated when scaled such that scores increase with attractiveness, and this correlation typically has a genetic component. Such traits can be genetically correlated due to genes that affect both traits (“pleiotropy”) and/or because assortative mating causes statistical correlations to develop between selected alleles across the traits (“gametic phase disequilibrium”). In this study, we modeled the covariation between monozygotic and dizygotic twins, their siblings, and their parents (total N = 7,905) to elucidate the nature of the correlation between two potentially sexually selected traits in humans: height and IQ. Unlike previous designs used to investigate the nature of the height–IQ correlation, the present design accounts for the effects of assortative mating and provides much less biased estimates of additive genetic, non-additive genetic, and shared environmental influences. Both traits were highly heritable, although there was greater evidence for non-additive genetic effects in males. After accounting for assortative mating, the correlation between height and IQ was found to be almost entirely genetic in nature. Model fits indicate that both pleiotropy and assortative mating contribute significantly and about equally to this genetic correlation. PMID:23593038

  18. VA-Index: Quantifying Assortativity Patterns in Networks with Multidimensional Nodal Attributes.

    Directory of Open Access Journals (Sweden)

    Konstantinos Pelechrinis

    Full Text Available Network connections have been shown to be correlated with structural or external attributes of the network vertices in a variety of cases. Given the prevalence of this phenomenon network scientists have developed metrics to quantify its extent. In particular, the assortativity coefficient is used to capture the level of correlation between a single-dimensional attribute (categorical or scalar of the network nodes and the observed connections, i.e., the edges. Nevertheless, in many cases a multi-dimensional, i.e., vector feature of the nodes is of interest. Similar attributes can describe complex behavioral patterns (e.g., mobility of the network entities. To date little attention has been given to this setting and there has not been a general and formal treatment of this problem. In this study we develop a metric, the vector assortativity index (VA-index for short, based on network randomization and (empirical statistical hypothesis testing that is able to quantify the assortativity patterns of a network with respect to a vector attribute. Our extensive experimental results on synthetic network data show that the VA-index outperforms a baseline extension of the assortativity coefficient, which has been used in the literature to cope with similar cases. Furthermore, the VA-index can be calibrated (in terms of parameters fairly easy, while its benefits increase with the (co-variance of the vector elements, where the baseline systematically over(underestimate the true mixing patterns of the network.

  19. VA-Index: Quantifying Assortativity Patterns in Networks with Multidimensional Nodal Attributes.

    Science.gov (United States)

    Pelechrinis, Konstantinos; Wei, Dong

    2016-01-01

    Network connections have been shown to be correlated with structural or external attributes of the network vertices in a variety of cases. Given the prevalence of this phenomenon network scientists have developed metrics to quantify its extent. In particular, the assortativity coefficient is used to capture the level of correlation between a single-dimensional attribute (categorical or scalar) of the network nodes and the observed connections, i.e., the edges. Nevertheless, in many cases a multi-dimensional, i.e., vector feature of the nodes is of interest. Similar attributes can describe complex behavioral patterns (e.g., mobility) of the network entities. To date little attention has been given to this setting and there has not been a general and formal treatment of this problem. In this study we develop a metric, the vector assortativity index (VA-index for short), based on network randomization and (empirical) statistical hypothesis testing that is able to quantify the assortativity patterns of a network with respect to a vector attribute. Our extensive experimental results on synthetic network data show that the VA-index outperforms a baseline extension of the assortativity coefficient, which has been used in the literature to cope with similar cases. Furthermore, the VA-index can be calibrated (in terms of parameters) fairly easy, while its benefits increase with the (co-)variance of the vector elements, where the baseline systematically over(under)estimate the true mixing patterns of the network. PMID:26816262

  20. The short- and long-term impact of an assortment reduction on category sales

    NARCIS (Netherlands)

    Sloot, Laurens M.; Fok, Dennis; Verhoef, Peter C.

    2006-01-01

    In a collaborative study with a major Dutch retailer, the authors assess the short- and long-term effects of a 25% item reduction on-category sales. On an aggregate level, a major assortment reduction can lead to substantive short-term category sales losses but only a weak negative long-term categor

  1. Genetic and socioeconomic study of mate choice in Latinos reveals novel assortment patterns.

    Science.gov (United States)

    Zou, James Y; Park, Danny S; Burchard, Esteban G; Torgerson, Dara G; Pino-Yanes, Maria; Song, Yun S; Sankararaman, Sriram; Halperin, Eran; Zaitlen, Noah

    2015-11-01

    Nonrandom mating in human populations has important implications for genetics and medicine as well as for economics and sociology. In this study, we performed an integrative analysis of a large cohort of Mexican and Puerto Rican couples using detailed socioeconomic attributes and genotypes. We found that in ethnically homogeneous Latino communities, partners are significantly more similar in their genomic ancestries than expected by chance. Consistent with this, we also found that partners are more closely related--equivalent to between third and fourth cousins in Mexicans and Puerto Ricans--than matched random male-female pairs. Our analysis showed that this genomic ancestry similarity cannot be explained by the standard socioeconomic measurables alone. Strikingly, the assortment of genomic ancestry in couples was consistently stronger than even the assortment of education. We found enriched correlation of partners' genotypes at genes known to be involved in facial development. We replicated our results across multiple geographic locations. We discuss the implications of assortment and assortment-specific loci on disease dynamics and disease mapping methods in Latinos.

  2. Spotting altruistic dictator game players and mingling with them : the elective assortation of classmates

    NARCIS (Netherlands)

    Pradel, Julia; Euler, Harald A.; Fetchenhauer, Detlef

    2009-01-01

    Altruism can evolve through assortation if the selfish advantage of egoistic individuals is outcompeted by the benefits of mutual cooperation between altruists. This selection process is possible if (a) individuals can distinguish altruists from egoists and (b) altruists cooperate electively with ot

  3. The small world phenomenon and assortative mixing in Polish corporate board and director networks

    Science.gov (United States)

    Sankowska, Anna; Siudak, Dariusz

    2016-02-01

    This paper investigates the corporate board and director networks in the Polish capital market in 2014. We examined real board and director networks in comparison with networks that were randomly constructed. Through empirical analyses, we demonstrated that the real networks have the characteristics of small-world networks. In addition, the networks are assortative and highly clustered, which imposes certain behaviors on them.

  4. Assortative mating and gene flow generate clinal phenological variation in trees

    Directory of Open Access Journals (Sweden)

    Soularue Jean-Paul

    2012-06-01

    Full Text Available Abstract Background On-going climate change is shifting the timing of bud burst (TBB of broad leaf and conifer trees in temperate areas, raising concerns about the abilities of natural populations to respond to these shifts. The level of expected evolutionary change depends on the level and distribution of genetic variation of TBB. While numerous experimental studies have highlighted the role of divergent selection in promoting clinal TBB differentiation, we explored whether the observed patterns of variation could be generated by the joint effects of assortative mating for TBB and gene flow among natural populations. We tested this hypothesis using an in silico approach based on quantitative genetic models. Results Our simulations showed that genetic clines can develop even without divergent selection. Assortative mating in association with environmental gradients substantially shifted the mean genetic values of populations. Owing to assortative mating, immigrant alleles were screened for proximal or distant populations depending on the strength of the environmental cline. Furthermore, we confirmed that assortative mating increases the additive genetic variance within populations. However, we observed also a rapid decline of the additive genetic variance caused by restricted gene flow between neighboring populations resulting from preferential matings between phenologically-matching phenotypes. Conclusions We provided evidence that the patterns of genetic variation of phenological traits observed in forest trees can be generated solely by the effects of assortative mating and gene flow. We anticipate that predicted temperature increases due to climate change will further enhance genetic differentiation across the landscape. These trends are likely to be reinforced or counteracted by natural selection if phenological traits are correlated to fitness.

  5. Assimilate partitioning during reproductive growth

    International Nuclear Information System (INIS)

    Leaves having various phyllotactic relationships to fruitlets were labeled for 1 hour with 10/sub r/Ci of 14CO2. Fruitlets were also labeled. Fruitlets did fix 14CO2. Translocation of radioactivity from the peel into the fruit occurred slowly and to a limited extent. No evidence of translocation out of the fruitlets was observed. Assimilate partitioning in avocado was strongly influenced by phyllotaxy. If a fruit and the labeled leaf had the same phyllotaxy then greater than 95% of the radiolabel was present in this fruit. When the fruit did not have the same phyllotaxy as the labeled leaf, the radiolabel distribution was skewed with 70% of the label going to a single adjacent position. Avocado fruitlets exhibit uniform labeling throughout a particular tissue. In avocado, assimilates preferentially move from leaves to fruits with the same phyllotaxy

  6. Assimilation, Criminality and Ethnic Conflict

    OpenAIRE

    Dasgupta, Indraneel; Mukherjee, Diganta

    2014-01-01

    We examine the consequences, of integrating large minorities into productivity-relevant majority ethno-linguistic norms, for distribution, ethnic conflict and crime. We develop a two-community model where such assimilation generates social gains by: (a) facilitating economic interaction, and (b) dampening religious or racial conflict over symbolic and normative contents of the public sphere. However, integration shifts the distribution of both material and symbolic goods against the minority....

  7. Financial assimilation of immigrants conference

    OpenAIRE

    anonymous

    2003-01-01

    On June 24, the Consumer and Community Affairs division of the Federal Reserve Bank of Chicago convened, “An Informed Discussion of the Financial Assimilation of Immigrants” in Des Moines, Iowa. The conference was part of the larger, long-term program by the Chicago Reserve Bank to study the ways and means by which immigrants to the United States access mainstream financial services. This Special Edition of PNV comprises summaries of each of the conference presentations.

  8. Wavelet Approximation in Data Assimilation

    Science.gov (United States)

    Tangborn, Andrew; Atlas, Robert (Technical Monitor)

    2002-01-01

    Estimation of the state of the atmosphere with the Kalman filter remains a distant goal because of high computational cost of evolving the error covariance for both linear and nonlinear systems. Wavelet approximation is presented here as a possible solution that efficiently compresses both global and local covariance information. We demonstrate the compression characteristics on the the error correlation field from a global two-dimensional chemical constituent assimilation, and implement an adaptive wavelet approximation scheme on the assimilation of the one-dimensional Burger's equation. In the former problem, we show that 99%, of the error correlation can be represented by just 3% of the wavelet coefficients, with good representation of localized features. In the Burger's equation assimilation, the discrete linearized equations (tangent linear model) and analysis covariance are projected onto a wavelet basis and truncated to just 6%, of the coefficients. A nearly optimal forecast is achieved and we show that errors due to truncation of the dynamics are no greater than the errors due to covariance truncation.

  9. Coevolutionary, coexisting learning and teaching agents model for prisoner’s dilemma games enhancing cooperation with assortative heterogeneous networks

    Science.gov (United States)

    Tanimoto, Jun

    2013-07-01

    Unlike other natural network systems, assortativity can be observed in most human social networks, although it has been reported that a social dilemma situation represented by the prisoner’s dilemma favors dissortativity to enhance cooperation. We established a new coevolutionary model for both agents’ strategy and network topology, where teaching and learning agents coexist. Remarkably, this model enables agents’ enhancing cooperation more than a learners-only model on a time-frozen scale-free network and produces an underlying assortative network with a fair degree of power-law distribution. The model may imply how and why assortative networks are adaptive in human society.

  10. From sparse to dense and from assortative to disassortative in online social networks.

    Science.gov (United States)

    Li, Menghui; Guan, Shuguang; Wu, Chensheng; Gong, Xiaofeng; Li, Kun; Wu, Jinshan; Di, Zengru; Lai, Choy-Heng

    2014-01-01

    Inspired by the analysis of several empirical online social networks, we propose a simple reaction-diffusion-like coevolving model, in which individuals are activated to create links based on their states, influenced by local dynamics and their own intention. It is shown that the model can reproduce the remarkable properties observed in empirical online social networks; in particular, the assortative coefficients are neutral or negative, and the power law exponents γ are smaller than 2. Moreover, we demonstrate that, under appropriate conditions, the model network naturally makes transition(s) from assortative to disassortative, and from sparse to dense in their characteristics. The model is useful in understanding the formation and evolution of online social networks.

  11. New Assortment of Sizing Adhesive%浆纱粘着剂新品种

    Institute of Scientific and Technical Information of China (English)

    刘海文; 何新勇; 张秀敏; 贾立霞; 王联军

    2001-01-01

    The general property , special property and major t echnical index of new assortment of sizing adhesive such as modified starch, mod ified polyvinyl alcohol, acrylic,polyester etc.the four assortments 21 kind products which are in initial use in practice at home and abroad have been intr oduced.%介绍了国内外生产实践中初见使用的一些浆纱粘着剂新品种,例变性淀粉类、变性 聚乙烯醇类、丙烯酸类、聚酯类等4大类21种产品的共性、特性和主要技术指标。

  12. Interactive computer program for learning genetic principles of segregation and independent assortment through meiosis.

    Science.gov (United States)

    Yang, Xiaoli; Ge, Rong; Yang, Yufei; Shen, Hao; Li, Yingjie; Tseng, Charles C

    2009-01-01

    Teaching fundamental principles of genetics such as segregation and independent assortment of genes could be challenging for high school and college biology instructors. Students without thorough knowledge in meiosis often end up of frustration and failure in genetics courses. Although all textbooks and laboratory manuals have excellent graphic demonstrations and photographs of meiotic process, students may not always master the concept due to the lack of hands-on exercise. In response to the need for an effective lab exercise to understand the segregation of allelic genes and the independent assortment of the unlinked genes, we developed an interactive program for students to manually manipulate chromosome models and visualize each major step of meiosis so that these two genetic principles can be thoroughly understood.

  13. Relative importance of social synergy, assortation and networks in the evolution of social cooperation

    CERN Document Server

    Montoreano, Claudia

    2013-01-01

    We compare the likelihood of different socially relevant features to allow the evolutionary emergence and maintenance of cooperation in a generalized variant of the iterated Prisoners Dilemma game. Results show that the average costs/benefit balance of cooperation is the primary constraint for its establishment and maintenance. Behavior increasing inclusive fitness such as assortation, homophily, kin-selection and tagging of individuals, is second in importance. Networks characteristics were the least important in favoring the establishment and maintenance of cooperation, despite being the most popular in recent research on the subject. Results suggest that inclusive fitness theory with its expansions to include assortative and economic considerations is more general, powerful and relevant in analyzing social phenomena than kin selection theory with its emphasis on genetic relatedness. Merging economics with evolutionary theory will be necessary to reveal more about the nature of social dynamics.

  14. Cytological evidence for assortment mitosis leading to loss of heterozygosity in rice.

    Science.gov (United States)

    Wang, Richard R-C; Li, Xiaomei; Chatterton, N Jerry

    2006-05-01

    In the root meristem cells of the rice line AMR, which causes loss of heterozygosity in its hybrids, both normal and assortment mitoses were observed. During normal mitosis, chromosomes did not form homologous pairs at metaphase; all chromosomes lined up at the equatorial plate and 2 chromatids of each chromosome disjoined at the centromere and moved toward opposite poles. During assortment mitosis, varying numbers of paired homologues were observed at mitotic metaphase. Two groups of 12 chromosomes separated and moved towards the opposite poles of daughter cells with few chromosomes having their chromatids separated at anaphase. These observations support the proposed mechanism that is responsible for early genotype fixation in rice hybrids involving AMR.

  15. Heterosexual romantic couples mate assortatively for facial symmetry, but not masculinity.

    Science.gov (United States)

    Burriss, Robert P; Roberts, S Craig; Welling, Lisa L M; Puts, David A; Little, Anthony C

    2011-05-01

    Preferences for partners with symmetric and sex-typical faces are well documented and considered evidence for the good-genes theory of mate choice. However, it is unclear whether preferences for these traits drive the real-world selection of mates. In two samples of young heterosexual couples from the United Kingdom (Study 1) and the United States (Study 2), the authors found assortment for facial symmetry but not for sex typicality or independently rated attractiveness. Within-couple similarity in these traits did not predict relationship duration or quality, although female attractiveness and relationship duration were negatively correlated among couples in which the woman was the more attractive partner. The authors conclude that humans may mate assortatively on facial symmetry, but this remains just one of the many physical and nonphysical traits to which people likely attend when forming romantic partnerships. This is also the first evidence that preferences for symmetry transfer from the laboratory to a real-world setting.

  16. Effect of genetic heterogeneity and assortative mating on linkage analysis: a simulation study.

    OpenAIRE

    Falk, C T

    1997-01-01

    Linkage studies of complex genetic traits raise questions about the effects of genetic heterogeneity and assortative mating on linkage analysis. To further understand these problems, I have simulated and analyzed family data for a complex genetic disease in which disease phenotype is determined by two unlinked disease loci. Two models were studied, a two-locus threshold model and a two-locus heterogeneity model. Information was generated for a marker locus linked to one of the disease-definin...

  17. The gender divide in urban China: Singlehood and assortative mating by age and education

    OpenAIRE

    Yue Qian; Zhenchao Qian

    2014-01-01

    Objective: Chinese media labels highly educated, urban women who are still single in their late 20s as "leftover ladies". We investigate whether indeed highly educated women are less likely to marry than their less-educated counterparts, and how assortative mating patterns by age and education play a role in singleness. Methods: We use data from the urban samples of the Chinese General Social Surveys in the 2000s. In the analysis we calculate marriage rates to examine the likelihood of ent...

  18. Assortative marriages by body mass index have increased simultaneously with the obesity epidemic

    Directory of Open Access Journals (Sweden)

    Teresa Adeltoft Ajslev

    2012-07-01

    Full Text Available Background: The genetic predisposition to obesity may have contributed to the obesity epidemic through assortative mating. We investigated whether spouses were positively assorted by body mass index (BMI; =kg/m2 in late childhood, and whether changes in assorted marriage by upper BMI-percentiles occurred during the obesity epidemic. Methods: In the Copenhagen School Health Records Register boys and girls with measures of BMI at age 13 years later became 37 792 spousal-pairs who married from 1945–2010. Trends in the spousal BMI correlations using sex-, age- and birth cohort-specific BMI z-scores across time were investigated. Odds ratios (ORs of marriage among spouses both with BMI z-scores >90th or >95th percentile compared with marriage among spouses ≤90th percentile were analysed for marriages entered during the years prior to (1945–1970, and during the obesity epidemic (1971–2010.Findings: Spousal BMI correlations were small and stayed similar across time. ORs of marriage among spouses with BMIs >90th percentile at age 13 were 1.21, 1.05–1.39, in 1945–1970, and increased to 1.63, 1.40–1.91, in 1971–2010 (p=0.006. ORs of marriage among spouses both >95th BMI percentile were higher and increased more; from 1.39, 1.10–1.81, to 2.39, 1.85–3.09 (p=0.004.Interpretation: Spousal correlations by pre-marital BMIs were stable during the past 65 years. Yet, assorted marriages between spouses with BMIs in the upper percentiles were observed and increased significantly across the two marriage periods, and this may possibly influence the following generations’ susceptibility to obesity.

  19. Why Does Spousal Education Matter for Earnings? Assortative Mating or Cross-productivity

    OpenAIRE

    Chong Huang; Hongbin Li; Pak Wai Liu; Junsen Zhang

    2006-01-01

    In interpreting the positive relationship between spousal education and one's earnings, economists have two major hypotheses: cross-productivity between couples and assortative mating. However, no prior empirical study has been able to separate the two effects. This paper empirically disentangles the two effects by using twins data that we collected from urban China. We have two major innovations: we use twins data to control for the unobserved mating effect in our estimations, and we estimat...

  20. Marketing Strategy Development Directions of Web Assortment in the Republic of Serbia

    OpenAIRE

    Jelena Končar; Zita Petrović-Katai; Goran Vukmirović

    2010-01-01

    Electronic commerce is a contemporary way of doing trade activities based on the use of information and communication technologies. In contemporary business conditions, trade faces numerous changes, which are mostly, before all, the result of market globalization, as well as information technology development. The Web assortment in electronic commerce is the key marketing instrument in a trade organization. The basic task of Serbian companies understands the need of tracking all the changes i...

  1. Growth and yield models, assortment type and analysis of deadwood in chestnut coppice

    Directory of Open Access Journals (Sweden)

    Marziliano PA

    2013-02-01

    Full Text Available Chestnut (Castanea sativa MILL. is one of the most important forest tree species in Europe, and it is considered a symbol of the natural vegetation in southern Europe. In Calabria (southern Italy chestnut forest covers an area of approximately 87000 hectares, most of which (about 80% managed as coppice. In this study a growth and yield table has been elaborated. Thurthermore, assortment type and quantity of deadwood have been evaluated according to age of coppice and forest fire prevention, respectively. The study site is located in the “Presila of Catanzaro” and the research was carried out in 15 plots; the age of the examined stands ranged from 2 to 50 years old. More than 30000 shoots per hectare were recorded in the first two years after coppicing. As opposed, about 2300 and 1000 shoots per hectare were observed 15 and 50 years after coppicing, respectively. The culmination of the mean annual increment of the forest standing volume (16 m3 ha-1 year-1 was highlighted 25 years after coppicing, while the current annual increment culmination (21 m3 ha-1 year-1 was observed at 15 years. Fifteen years after coppicing, most of the wood production was constituted by small dimension assortments. Twenty five years after coppicing small and large poles were the prevailing assortments while telegraph poles and timber beams increased after 50 years. The amount of deadwood in forest ranged between 11.9 and 68.7 m3 ha-1. The largest component was represented by standing dead shoots. The results show that coppice management can be adopted even if the main purpose of the chestnut stand is the production of large size assortments. In chestnut coppice, highly vulnerable to fire, the reduction of stand density with silvicultural practices (thinning and displacement is the main way to promote the efficiency of forest and a higher strength and resiliency against forest fire.

  2. VA-Index: Quantifying Assortativity Patterns in Networks with Multidimensional Nodal Attributes

    OpenAIRE

    Konstantinos Pelechrinis; Dong Wei

    2016-01-01

    Network connections have been shown to be correlated with structural or external attributes of the network vertices in a variety of cases. Given the prevalence of this phenomenon network scientists have developed metrics to quantify its extent. In particular, the assortativity coefficient is used to capture the level of correlation between a single-dimensional attribute (categorical or scalar) of the network nodes and the observed connections, i.e., the edges. Nevertheless, in many cases a mu...

  3. Quantifying the risk of pandemic influenza virus evolution by mutation and re-assortment.

    Science.gov (United States)

    Reperant, Leslie A; Grenfell, Bryan T; Osterhaus, Albert D M E

    2015-12-01

    Large outbreaks of zoonotic influenza A virus (IAV) infections may presage an influenza pandemic. However, the likelihood that an airborne-transmissible variant evolves upon zoonotic infection or co-infection with zoonotic and seasonal IAVs remains poorly understood, as does the relative importance of accumulating mutations versus re-assortment in this process. Using discrete-time probabilistic models, we determined quantitative probability ranges that transmissible variants with 1-5 mutations and transmissible re-assortants evolve after a given number of zoonotic IAV infections. The systematic exploration of a large population of model parameter values was designed to account for uncertainty and variability in influenza virus infection, epidemiological and evolutionary processes. The models suggested that immunocompromised individuals are at high risk of generating IAV variants with pandemic potential by accumulation of mutations. Yet, both immunocompetent and immunocompromised individuals could generate high viral loads of single and double mutants, which may facilitate their onward transmission and the subsequent accumulation of additional 1-2 mutations in newly-infected individuals. This may result in the evolution of a full transmissible genotype along short chains of contact transmission. Although co-infection with zoonotic and seasonal IAVs was shown to be a rare event, it consistently resulted in high viral loads of re-assortants, which may facilitate their onward transmission among humans. The prevention or limitation of zoonotic IAV infection in immunocompromised and contact individuals, including health care workers, as well as vaccination against seasonal IAVs-limiting the risk of co-infection-should be considered fundamental tools to thwart the evolution of a novel pandemic IAV by accumulation of mutations and re-assortment.

  4. Prices and the assortment offer of the mineral fertilizers in the farmers’ opinion

    OpenAIRE

    Arkadiusz Piwowar

    2011-01-01

    The mineral fertilizers are the basic means of production used by agriculturalists in order to improve the size and quality of the cultivated plants. The retail prices of the most popular mineral fertilizers have risen in the last years. The paper discusses the research results concerning the agriculturalists' opinion about the mineral fertilizers’ prices and assortment in the market. The research revealed that the high prices and their disadvantageous relation to the fruits' of the earth pri...

  5. From Assortative to Ashortative Coupling: Men's Height, Height Heterogamy, and Relationship Dynamics in the United States

    OpenAIRE

    Abigail Weitzman; Dalton Conley

    2014-01-01

    Studies of online dating suggest that physical attraction is a key factor in early relationship formation, but say little about the role of attractiveness in longer-term relationships. Meanwhile, assortative coupling and exchange models widely employed in demographic research overlook the powerful sorting function of initial and sustained physical attraction. This article observes the effects of one physical characteristic of men--height--on various relationship outcomes in longer-term relati...

  6. Ensemble Data Assimilation: Algorithms and Software

    OpenAIRE

    Nerger, Lars

    2014-01-01

    Ensemble data assimilation is nowadays applied to various problems to estimate a model state and model parameters by combining the model predictions with observational data. At the Alfred Wegener Institute, the assimilation focuses on ocean-sea ice models and coupled ocean-biogeochemical models. The high dimension of realistic models requires particularly efficient algorithms that are also usable on supercomputers. For the application of such filters, the Parallel Data Assimilation Framework ...

  7. On the mathematics of data assimilation

    OpenAIRE

    Talagrand, Olivier

    2011-01-01

    The problem of convergence of a “forward-backward” assimilation is considered for the most general dynamical system. Using elementary techniques of stability theory, it is shown that the variation, over one assimilation cycle, of the difference between the assimilating model and the state to be reconstructed is, to the first order, determined by a perfectly defined amplification matrix. This leads to a straightforward criterion for convergence, depending on the eigenvalues of that matrix. Th...

  8. Immigrant Job Search Assimilation in Canada

    OpenAIRE

    Bowlus, Audra J.; Miyairi, Masashi; Robinson, Chris

    2013-01-01

    Immigrant assimilation is a major issue in many countries. While most of the literature studies assimilation through a human capital framework, we examine the role of job search assimilation. To do so, we estimate an equilibrium search model of immigrants operating in the same labor market as natives, where newly arrived immigrants have lower job offer arrival rates than natives but can acquire the same arrival rates according to a stochastic process. Using Canadian panel data, we find substa...

  9. Assimilation and integration of immigrants in Europe

    OpenAIRE

    Aleksynska, Mariya; ALGAN, Yann

    2010-01-01

    This paper documents assimilation of immigrants in European destinations along cultural, civic, and economic dimensions, distinguishing by immigrants' generation, duration of stay, and origin. Based on the European Social Survey, it suggests that assimilation may have multiple facets, and take place at different speed depending on the outcome in question. While assimilation along some economic and cultural outcomes may be correlated, such correlations are not systematic, and imply that progre...

  10. Outline of an Economic Theory of Assimilation

    OpenAIRE

    Schaeffer, Peter V.

    2006-01-01

    In an age of mass immigration, assimilation is critical not only to the success of the immigrants but also to the success of their descendants and of the host society. This paper presents an outline for an economic theory of assimilation based on the assumption that both immigrants and natives invest in assimilation, that both may in fact move in the direction of the "other," and that the notion of "distance" is subjective and reversible.

  11. Review: Game theory of public goods in one-shot social dilemmas without assortment.

    Science.gov (United States)

    Archetti, Marco; Scheuring, István

    2012-04-21

    We review the theory of public goods in biology. In the N-person prisoner's dilemma, where the public good is a linear function of the individual contributions, cooperation requires some form of assortment, for example due to kin discrimination, population viscosity or repeated interactions. In most social species ranging from bacteria to humans, however, public goods are usually a non-linear function of the contributions, which makes cooperation possible without assortment. More specifically, a polymorphic state can be stable in which cooperators and non-cooperators coexist. The existence of mixed equilibria in public goods games is a fundamental result in the study of cooperation that has been overlooked so far, because of the disproportionate attention given to the two- and N-person prisoner's dilemma. Methods and results from games with pairwise interactions or linear benefits cannot, in general, be extended to the analysis of public goods. Game theory helps explain the production of public goods in one-shot, N-person interactions without assortment, it leads to predictions that can be easily tested and allows a prescriptive approach to cooperation.

  12. Assessment of the effect of quality factors on the assortment structure in poplar plantations

    Directory of Open Access Journals (Sweden)

    Danilović Milorad

    2008-01-01

    Full Text Available Quality factors affecting the assortment quality structure in poplar plantations were researched on nine temporary sample plots in the period 1997-2004, from the aspect of the implementation of roundwood standards. Sample plots were selected depending on the factors, the effect of which was studied. The following factors were researched: clonal species, planting pattern, flood risk, pruning of branches, plantation position and age. The study was performed by the original methodology. Based on the study results, it is concluded that knots have the highest effect on the assortment quality structure in poplar plantations, regardless of the site and stand conditions. Their effect rises significantly with the increase of tree diameter. Also, the analyses show that the number of large and rotten knots on the tree trunk increases considerably with the older age. In the flooded area, the sweep of the lower part of the stem is more intensive and multiple curvatures are frequent on the trees growing immediately along the river, whereas curvature decreases with the distance from the river bank. Based on the study results, it is concluded that the percentage of best quality assortments is considerably reduced by the above wood defects.

  13. Povezave med kakovostjo bukovih dreves in iz njih izdelanih sortimentov: Links between beech tree quality and assortments made of them:

    OpenAIRE

    Marenče, Jurij; Šega, Bogdan

    2015-01-01

    In our research we dealt with the standing tree, estimation of the standing tree, evaluation of its quality and evaluation of quality of assortments made of it. Thereby we critically discussed diverse criteria, currently used in the practice - the five-grade scale for standing tree evaluation, used on permanent sampling plots, and current standards for evaluating the quality of the produced assortments. On the basis of a small analyzed sample of the evaluated and afterwards felled trees we we...

  14. Retail Choice Architecture: The Effects of Benefit- and Attribute-Based Assortment Organization on Consumer Perceptions and Choice

    OpenAIRE

    Cait Poynor Lamberton; Kristin Diehl

    2013-01-01

    This article explores the effects of two distinct retail choice architectures--those that organize assortments by attributes and those that organize items by benefits. Relative to attribute-based organizations, benefit-based organizations lead to more abstract construal and heighten similarity perceptions among items in an assortment. Such changes in similarity perceptions alter consumers' strength of preference among items: when choosing from benefit- as opposed to attribute-based organizati...

  15. No evidence for size-assortative mating in the wild despite mutual mate choice in sex-role-reversed pipefishes

    OpenAIRE

    Mobley, K.; Abou Chakra, M.; Jones, A.

    2014-01-01

    Size-assortative mating is a nonrandom association of body size between members of mating pairs and is expected to be common in species with mutual preferences for body size. In this study, we investigated whether there is direct evidence for size-assortative mating in two species of pipefishes, Syngnathus floridae and S. typhle, that share the characteristics of male pregnancy, sex-role reversal, and a polygynandrous mating system. We take advantage of microsatellite- based “genetic-capture”...

  16. The strength of assortative mating for flowering date and its basis in individual variation in flowering schedule.

    Science.gov (United States)

    Weis, A E; Nardone, E; Fox, G A

    2014-10-01

    Although it has been widely asserted that plants mate assortatively by flowering time, there is virtually no published information on the strength or causes of phenological assortment in natural populations. When strong, assortative mating can accelerate the evolution of plant reproductive phenology through its inflationary effect on genetic variance. We estimated potential assortative mating for flowering date in 31 old-field species in Ontario, Canada. For each species, we constructed a matrix of pairwise mating probabilities from the individual flowering schedules, that is the number of flower deployed on successive dates. The matrix was used to estimate the phenotypic correlation between mates, ρ, for flowering date. We also developed a measure of flowering synchrony within species, S, based upon the eigenstructure of the mating matrix. The mean correlation between pollen recipients and potential donors for flowering date was ρ=0.31 (range: 0.05-0.63). A strong potential for assortative mating was found among species with high variance in flowering date, flowering schedules of short duration and skew towards early flower deployment. Flowering synchrony, S, was negatively correlated with potential assortment (r= -0.49), but we go on to show that although low synchrony is a necessary condition for phenological assortative mating, it may not be sufficient to induce assortment for a given phenological trait. The potential correlation between mates showed no seasonal trend; thus, as climate change imposes selection on phenology through longer growing seasons, spring-flowering species are no more likely to experience an accelerated evolutionary response than summer species.

  17. Data Assimilation in Marine Models

    DEFF Research Database (Denmark)

    Frydendall, Jan

    This thesis consists of six research papers published or submitted for publication in the period 2006-2009 together with a summary report. The main topics of this thesis are nonlinear data assimilation techniques and estimation in dynamical models. The focus has been on the nonlinear filtering te...... for the Fokker-Planck equation on a 2 dimensional flexible mesh system. The report details the construction of the finite element solver and investigates the potential benefits of a parallel FORTRAN implementation through a series of experiments....

  18. Towards Operational Data Assimilation in the North and Baltic Seas with the Parallel Data Assimilation Framework

    OpenAIRE

    Nerger, Lars; Loza, Svetlana; Schröter, Jens; Hiller, Wolfgang; F. Janssen

    2010-01-01

    Within the GMES-related project DeMarine Environment, the operational circulation model of the German Maritime and Hydrographic Agency (BSH) is extended into a data assimilation system. The aim of the data assimilation is to improve the forecast of sea surface height, temperatura, currents and salinity in the North and Baltic Seas. For the data assimilation component, the Parallel Data Assimilation Framework (PDAF, http://pdaf.awi.de) is coupled to the operational circulation model. PDAF prov...

  19. Active phenotypic assortment in mate selection: self-descriptions and sought-for attributes of mates in dating advertisements.

    Science.gov (United States)

    Sakai, D K; Johnson, R C

    1997-01-01

    Assortative mating results both from social homogamy (coming for similar environments) and active phenotypic assortment (seeking a mate with desired attributes). Dating advertisements provide a means of assessing the role of active phenotypic assortment in the absence of social homogamy. The relative frequency of mention of different attributes (given limited advertising space) is informative regarding the salience of these attributes in active phenotypic assortment. Sex differences in self descriptions and in attributes desired in others in dating advertisements provide a means of evaluating sociobiological issues. Data were analyzed from 191 ads placed by females and 253 ads placed by males seeking to meet members of the opposite sex. The most frequently mentioned attributes are age, race, occupation, moral characteristics, and physical attractiveness. While close to 80 per cent of the advertisers provided information concerning their own race/ethnicity, only a minority of those providing such information limited their quest for a partner to members of their own race/ethnicity. There is substantial assortative mating for religion, family background, status, and educational attainment, yet these attributes are rarely (religion and education) or never (family background) mentioned in advertisements, suggesting that assortative mating on these dimensions may be solely a consequence of social homogamy.

  20. Compensation for Complete Assimilation in Speech Perception: The Case of Korean Labial-to-Velar Assimilation

    Science.gov (United States)

    Mitterer, Holger; Kim, Sahyang; Cho, Taehong

    2013-01-01

    In connected speech, phonological assimilation to neighboring words can lead to pronunciation variants (e.g., "garden bench" [arrow right] "garde'm' bench"). A large body of literature suggests that listeners use the phonetic context to reconstruct the intended word for assimilation types that often lead to incomplete assimilations (e.g., a…

  1. Multiple mating reveals complex patterns of assortative mating by personality and body size.

    Science.gov (United States)

    Montiglio, Pierre-Olivier; Wey, Tina W; Chang, Ann T; Fogarty, Sean; Sih, Andrew

    2016-01-01

    Understanding patterns of non-random mating is central to predicting the consequences of sexual selection. Most studies quantifying assortative mating focus on testing for correlations among partners' phenotypes in mated pairs. Few studies have distinguished between assortative mating arising from preferences for similar partners (expressed by all or a subset of the population) vs. from phenotypic segregation in the environment. Also, few studies have assessed the robustness of assortative mating against temporal changes in social conditions. We tracked multiple matings by stream water striders (Aquarius remigis) across variable social conditions to investigate mating patterns by both body size and behavioural type (personality). We documented temporal changes in partner availability and used a mixed model approach to analyse individual behaviours and changes in mating status recorded on an hourly basis. We assessed whether all or only a subset of individuals in the population expressed a tendency to mate with similar phenotypes. Our analyses took into account variation in the level of competition and in the phenotypes of available partners. Males and females exhibited significant assortative mating by body size: the largest males and females, and the smallest males and females mated together more often than random. However, individuals of intermediate size were equally likely to mate with small, intermediate or large partners. Individuals also displayed two contrasting patterns of assortative mating by personality (activity level). Individuals generally mated preferentially with partners of similar activity level. However, beyond that general trend, individuals with more extreme personalities tended to exhibit disassortative mating: the most active males mated disproportionately with less active females and the least active males tended to mate with more active females. Our analyses thus revealed multiple, distinct patterns of nonrandom mating. These mating

  2. Assortative mating and differential male mating success in an ash hybrid zone population

    Directory of Open Access Journals (Sweden)

    Frascaria-Lacoste Nathalie

    2006-11-01

    Full Text Available Abstract Background The structure and evolution of hybrid zones depend mainly on the relative importance of dispersal and local adaptation, and on the strength of assortative mating. Here, we study the influence of dispersal, temporal isolation, variability in phenotypic traits and parasite attacks on the male mating success of two parental species and hybrids by real-time pollen flow analysis. We focus on a hybrid zone population between the two closely related ash species Fraxinus excelsior L. (common ash and F. angustifolia Vahl (narrow-leaved ash, which is composed of individuals of the two species and several hybrid types. This population is structured by flowering time: the F. excelsior individuals flower later than the F. angustifolia individuals, and the hybrid types flower in-between. Hybrids are scattered throughout the population, suggesting favorable conditions for their local adaptation. We estimate jointly the best-fitting dispersal kernel, the differences in male fecundity due to variation in phenotypic traits and level of parasite attack, and the strength of assortative mating due to differences in flowering phenology. In addition, we assess the effect of accounting for genotyping error on these estimations. Results We detected a very high pollen immigration rate and a fat-tailed dispersal kernel, counter-balanced by slight phenological assortative mating and short-distance pollen dispersal. Early intermediate flowering hybrids, which had the highest male mating success, showed optimal sex allocation and increased selfing rates. We detected asymmetry of gene flow, with early flowering trees participating more as pollen donors than late flowering trees. Conclusion This study provides striking evidence that long-distance gene flow alone is not sufficient to counter-act the effects of assortative mating and selfing. Phenological assortative mating and short-distance dispersal can create temporal and spatial structuring that appears

  3. Data Assimilation - Advances and Applications

    Energy Technology Data Exchange (ETDEWEB)

    Williams, Brian J. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2014-07-30

    This presentation provides an overview of data assimilation (model calibration) for complex computer experiments. Calibration refers to the process of probabilistically constraining uncertain physics/engineering model inputs to be consistent with observed experimental data. An initial probability distribution for these parameters is updated using the experimental information. Utilization of surrogate models and empirical adjustment for model form error in code calibration form the basis for the statistical methodology considered. The role of probabilistic code calibration in supporting code validation is discussed. Incorporation of model form uncertainty in rigorous uncertainty quantification (UQ) analyses is also addressed. Design criteria used within a batch sequential design algorithm are introduced for efficiently achieving predictive maturity and improved code calibration. Predictive maturity refers to obtaining stable predictive inference with calibrated computer codes. These approaches allow for augmentation of initial experiment designs for collecting new physical data. A standard framework for data assimilation is presented and techniques for updating the posterior distribution of the state variables based on particle filtering and the ensemble Kalman filter are introduced.

  4. The Race Race: Assimilation in America

    Science.gov (United States)

    Balis, Andrea; Aman, Michael

    2013-01-01

    Can race and assimilation be taught? Interdisciplinary pedagogy provides a methodology, context, and use of nontraditional texts culled from American cultural history such as from, theater and historical texts. This approach and these texts prove useful for an examination of race and assimilation in America. The paper describes a course that while…

  5. Data assimilation a mathematical introduction

    CERN Document Server

    Law, Kody; Zygalakis, Konstantinos

    2015-01-01

    This book provides a systematic treatment of the mathematical underpinnings of work in data assimilation, covering both theoretical and computational approaches. Specifically the authors develop a unified mathematical framework in which a Bayesian formulation of the problem provides the bedrock for the derivation, development and analysis of algorithms; the many examples used in the text, together with the algorithms which are introduced and discussed, are all illustrated by the MATLAB software detailed in the book and made freely available online. The book is organized into nine chapters: the first contains a brief introduction to the mathematical tools around which the material is organized; the next four are concerned with discrete time dynamical systems and discrete time data; the last four are concerned with continuous time dynamical systems and continuous time data and are organized analogously to the corresponding discrete time chapters. This book is aimed at mathematical researchers interested in a sy...

  6. Justifying Educational Acquaintance with the Moral Horrors of History on Psycho-Social Grounds: "Facing History and Ourselves" in Critical Perspective

    Science.gov (United States)

    Maxwell, Bruce

    2008-01-01

    This paper challenges a pervasive curricular justification for educationally acquainting young people with stories of genocide and other moral horrors from history. According to this justification, doing so favours the development of psycho-social soft skills connected with interpersonal awareness and the establishment and maintenance of positive…

  7. Recent social environment affects colour-assortative shoaling in juvenile angelfish (Pterophyllum scalare).

    Science.gov (United States)

    Gómez-Laplaza, Luis M

    2009-09-01

    Theory predicts that fish should show colour-assortative shoaling in order to avoid the oddity effect whereby individuals that differ in some feature from the group majority appear to incur increased risk of predation. It has also been shown that early experience plays an important role in affecting social preferences in some fish species. In this study, the importance of colour phenotype in promoting assortative shoaling and the role played by the recent social environment on its expression were investigated in juvenile angelfish, Pterophyllum scalare. Individuals of the uniformly black and golden colour morphs were housed in a group with conspecifics of like and unlike body colour to themselves, as well as in mixed-colour groups for 4 weeks. Subsequently, they were subjected to a binary choice to shoal with a group of conspecifics composed of unfamiliar fish of either a like or unlike colour phenotype to themselves. The response of the individuals to the colour attributes of the shoals was related to their recent social environment. Fish in like- and mixed-colour previous treatments showed a preferential association with like colour conspecifics. In contrast, the shoaling behaviour exhibited by fish previously maintained with a group of unlike-coloured conspecifics (cross-housed treatment) indicated no significant preference for any of the shoals. The results suggest that angelfish use body colouration as an intraspecific shoaling cue and that learning, in the form of recent familiarization with a specific colour phenotype of conspecifics, can affect colour-assortative shoaling preferences in this species. This learning component of the choice need not be restricted to early developmental stages. PMID:19376208

  8. PHYLLOXERA-RESISTANT HYBRID FORM OF GRAPES OF TECHNICAL SORTS FOR IMPROVING THE ASSORTMENT

    OpenAIRE

    Larkina M. D.; Nikulushkina G. E.

    2015-01-01

    Many old varieties of grapes do not meet modern requirements, so there is a need for improved assortment of new high-quality varieties. The translation of the vineyards of the black sea coast of the Krasnodar region on inoculated culture is not fully decided the fate of the viticulture of the area. Weak resistance of American rootstocks to increased content of calcium and salts in the soil, caused the weakening of the bushes, reducing the vigor of the shoots, their maturation and yield of gra...

  9. Marketing Strategy Development Directions of Web Assortment in the Republic of Serbia

    Directory of Open Access Journals (Sweden)

    Jelena Končar

    2010-06-01

    Full Text Available Electronic commerce is a contemporary way of doing trade activities based on the use of information and communication technologies. In contemporary business conditions, trade faces numerous changes, which are mostly, before all, the result of market globalization, as well as information technology development. The Web assortment in electronic commerce is the key marketing instrument in a trade organization. The basic task of Serbian companies understands the need of tracking all the changes in the business environment on the global market with a view of meeting consumers requirements and needs. Business success of an e-commerce trader, besides other factors, greatly depends on the adequate choice of sales programs.

  10. [The marketing analysis of assortment of market of pharmaceuticals applied in treatment of psoriasis in Ukraine].

    Science.gov (United States)

    Kotvitskaya, A A; Karlo, V V

    2013-01-01

    The analysis of assortment of pharmaceuticals for treatment of psoriasis recommended by Minzdrav of Ukraine and present at the national pharmaceutical market is made. The characteristics of distribution of national and foreign producers of antihistamine and anti-psoriatic pharmaceuticals are established The availability of particular medicinal forms of various producers is analyzed too. The characteristics and tendencies in consumption of these groups of pharmaceuticals in natural and monetary units are analyzed including dynamics of changes of mean wholesale prices during the analyzed period.

  11. Assortment of Deep Mantle Fluids and Their Products in Kimberlites from China

    Institute of Scientific and Technical Information of China (English)

    ZHAO Lei; HAO Jinhua; DING Yifei; LIU Yulong

    2004-01-01

    Based on studies of petrography, mineralogy and mineral chemistry, deep mantle fluids and their products in kimberlites and diamonds can be assorted into the ultradeep fluid-transmitted minerals with an oxygen-free feature, the deep fluid metasomatized-minerals characterized by enrichment in TiO2, K2O, BaO, REE and Fe3+, and the deep fluidreformed minerals. The three types show a successive descent in fluid origin depth and metasomatism strength, and they have brought forth a series of corresponding metasomatic products.

  12. A New Approach to Data Assimilation

    Institute of Scientific and Technical Information of China (English)

    Wang Bin; ZHAO Ying

    2006-01-01

    A significant attempt to design a timesaving and efficient four-dimensional variational data assimilation dimensional variational data assimilation of mapped observation (3DVM)' is proposed, based on the new concept of mapped observation and the new idea of backward 4DVar. Like the available 4DVar, 3DVM produces an optimal initial condition (IC) that is consistent with the prediction model due to the inclusion of model constraints and best fits the observations in the assimilation window through the model solution trajectory. Different from the 4DVar, the IC derived from 3DVM is located at the end of the assimilation window rather than at the beginning conventionally. This change greatly reduces the computing cost for the new approach, which is almost the same as that of the three-dimensional variational data assimilation (3DVar). Especially, such a change is able to improve assimilation accuracy because it does not need the tangential linear and adjoint approximations to calculate the gradient of cost function. Therefore,in numerical test, the new approach produces better IC than 4DVar does for 72-h simulation of TY9914(Dan), by assimilating the three-dimensional fields of temperature and wind retrieved from the Advanced Microwave Sounding Unit-A (AMSU-A) observations. Meanwhile, it takes only 1/7 of the computing cost that the 4DVar requires for the same initialization with the same retrieved data.

  13. Positive network assortativity of influenza vaccination at a high school: implications for outbreak risk and herd immunity.

    Science.gov (United States)

    Barclay, Victoria C; Smieszek, Timo; He, Jianping; Cao, Guohong; Rainey, Jeanette J; Gao, Hongjiang; Uzicanin, Amra; Salathé, Marcel

    2014-01-01

    Schools are known to play a significant role in the spread of influenza. High vaccination coverage can reduce infectious disease spread within schools and the wider community through vaccine-induced immunity in vaccinated individuals and through the indirect effects afforded by herd immunity. In general, herd immunity is greatest when vaccination coverage is highest, but clusters of unvaccinated individuals can reduce herd immunity. Here, we empirically assess the extent of such clustering by measuring whether vaccinated individuals are randomly distributed or demonstrate positive assortativity across a United States high school contact network. Using computational models based on these empirical measurements, we further assess the impact of assortativity on influenza disease dynamics. We found that the contact network was positively assortative with respect to influenza vaccination: unvaccinated individuals tended to be in contact more often with other unvaccinated individuals than with vaccinated individuals, and these effects were most pronounced when we analyzed contact data collected over multiple days. Of note, unvaccinated males contributed substantially more than unvaccinated females towards the measured positive vaccination assortativity. Influenza simulation models using a positively assortative network resulted in larger average outbreak size, and outbreaks were more likely, compared to an otherwise identical network where vaccinated individuals were not clustered. These findings highlight the importance of understanding and addressing heterogeneities in seasonal influenza vaccine uptake for prevention of large, protracted school-based outbreaks of influenza, in addition to continued efforts to increase overall vaccine coverage.

  14. Positive network assortativity of influenza vaccination at a high school: implications for outbreak risk and herd immunity.

    Directory of Open Access Journals (Sweden)

    Victoria C Barclay

    Full Text Available Schools are known to play a significant role in the spread of influenza. High vaccination coverage can reduce infectious disease spread within schools and the wider community through vaccine-induced immunity in vaccinated individuals and through the indirect effects afforded by herd immunity. In general, herd immunity is greatest when vaccination coverage is highest, but clusters of unvaccinated individuals can reduce herd immunity. Here, we empirically assess the extent of such clustering by measuring whether vaccinated individuals are randomly distributed or demonstrate positive assortativity across a United States high school contact network. Using computational models based on these empirical measurements, we further assess the impact of assortativity on influenza disease dynamics. We found that the contact network was positively assortative with respect to influenza vaccination: unvaccinated individuals tended to be in contact more often with other unvaccinated individuals than with vaccinated individuals, and these effects were most pronounced when we analyzed contact data collected over multiple days. Of note, unvaccinated males contributed substantially more than unvaccinated females towards the measured positive vaccination assortativity. Influenza simulation models using a positively assortative network resulted in larger average outbreak size, and outbreaks were more likely, compared to an otherwise identical network where vaccinated individuals were not clustered. These findings highlight the importance of understanding and addressing heterogeneities in seasonal influenza vaccine uptake for prevention of large, protracted school-based outbreaks of influenza, in addition to continued efforts to increase overall vaccine coverage.

  15. Brief report on the effect of providing single versus assorted brand name condoms to hospital patients: a descriptive study

    Directory of Open Access Journals (Sweden)

    Cagle Henry H

    2001-06-01

    Full Text Available Abstract Objectives This study examined condom acquisition by persons in a hospital setting when single versus assorted brand name condoms were provided. Methods Condom receptacles were placed in exam rooms of two clinics. During Phase 1, a single brand name was provided; for Phase 2, assorted brand names were added. Number of condoms taken was recorded for each phase. Results For one clinic there was nearly a two-fold increase in number of condoms taken (Phase 1 to Phase 2; for the second clinic there was negligible difference in number of condoms taken. Conclusions The provision of assorted brand name condoms, over a single brand name, can serve to increase condom acquisition. Locations of condoms and target population characteristics are related factors.

  16. Assortative mating and the maintenance of population structure in a natural hybrid zone.

    Science.gov (United States)

    Culumber, Zachary W; Ochoa, Olivia M; Rosenthal, Gil G

    2014-08-01

    Understanding the factors that give rise to natural hybrid zones and govern their dynamics and structure is important to predicting the evolutionary consequences of hybridization. Here we use a combination of multigenerational population genetic data, mating patterns from a natural population, behavioral assays, and mark-recapture data within clinal hybrid zones of the genus Xiphophorus to test the role of assortative mating in maintaining population structure and the potential for ongoing genetic exchange between heterospecifics. Our data demonstrate that population structure is temporally robust and driven largely by assortative mating stemming from precopulatory isolation between pure species. Furthermore, mark-recapture data revealed that rates of migration within the same stream reach are far below the level needed to support population structure. In contrast to many empirical studies of natural hybrid zones, there appeared to be no hybrid male dysfunction or discrimination against hybrid males by pure parental females, and hybrid females mated and associated with pure species and hybrid males at random. Despite strong isolation between pure parentals, hybrids therefore can act as a conduit for genetic exchange between heterospecifics, which has been shown to increase the tempo of evolutionary change. Additionally, our findings highlight the complexity of natural hybrid zone dynamics, demonstrating that sexual and ecological selection together can give rise to patterns that do not fit classical models of hybrid zone evolution.

  17. Assortative mating and the maintenance of population structure in a natural hybrid zone.

    Science.gov (United States)

    Culumber, Zachary W; Ochoa, Olivia M; Rosenthal, Gil G

    2014-08-01

    Understanding the factors that give rise to natural hybrid zones and govern their dynamics and structure is important to predicting the evolutionary consequences of hybridization. Here we use a combination of multigenerational population genetic data, mating patterns from a natural population, behavioral assays, and mark-recapture data within clinal hybrid zones of the genus Xiphophorus to test the role of assortative mating in maintaining population structure and the potential for ongoing genetic exchange between heterospecifics. Our data demonstrate that population structure is temporally robust and driven largely by assortative mating stemming from precopulatory isolation between pure species. Furthermore, mark-recapture data revealed that rates of migration within the same stream reach are far below the level needed to support population structure. In contrast to many empirical studies of natural hybrid zones, there appeared to be no hybrid male dysfunction or discrimination against hybrid males by pure parental females, and hybrid females mated and associated with pure species and hybrid males at random. Despite strong isolation between pure parentals, hybrids therefore can act as a conduit for genetic exchange between heterospecifics, which has been shown to increase the tempo of evolutionary change. Additionally, our findings highlight the complexity of natural hybrid zone dynamics, demonstrating that sexual and ecological selection together can give rise to patterns that do not fit classical models of hybrid zone evolution. PMID:25058282

  18. Extended inclusive fitness theory: synergy and assortment drives the evolutionary dynamics in biology and economics.

    Science.gov (United States)

    Jaffe, Klaus

    2016-01-01

    W.D. Hamilton's Inclusive Fitness Theory explains the conditions that favor the emergence and maintenance of social cooperation. Today we know that these include direct and indirect benefits an agent obtains by its actions, and through interactions with kin and with genetically unrelated individuals. That is, in addition to kin-selection, assortation or homophily, and social synergies drive the evolution of cooperation. An Extended Inclusive Fitness Theory (EIFT) synthesizes the natural selection forces acting on biological evolution and on human economic interactions by assuming that natural selection driven by inclusive fitness produces agents with utility functions that exploit assortation and synergistic opportunities. This formulation allows to estimate sustainable cost/benefit threshold ratios of cooperation among organisms and/or economic agents, using existent analytical tools, illuminating our understanding of the dynamic nature of society, the evolution of cooperation among kin and non-kin, inter-specific cooperation, co-evolution, symbioses, division of labor and social synergies. EIFT helps to promote an interdisciplinary cross fertilization of the understanding of synergy by, for example, allowing to describe the role for division of labor in the emergence of social synergies, providing an integrated framework for the study of both, biological evolution of social behavior and economic market dynamics. Another example is a bio-economic understanding of the motivations of terrorists, which identifies different forms of terrorism. PMID:27468393

  19. Geography, assortative mating, and the effects of sexual selection on speciation with gene flow.

    Science.gov (United States)

    Servedio, Maria R

    2016-01-01

    Theoretical and empirical research on the evolution of reproductive isolation have both indicated that the effects of sexual selection on speciation with gene flow are quite complex. As part of this special issue on the contributions of women to basic and applied evolutionary biology, I discuss my work on this question in the context of a broader assessment of the patterns of sexual selection that lead to, versus inhibit, the speciation process, as derived from theoretical research. In particular, I focus on how two factors, the geographic context of speciation and the mechanism leading to assortative mating, interact to alter the effect that sexual selection through mate choice has on speciation. I concentrate on two geographic contexts: sympatry and secondary contact between two geographically separated populations that are exchanging migrants and two mechanisms of assortative mating: phenotype matching and separate preferences and traits. I show that both of these factors must be considered for the effects of sexual selection on speciation to be inferred. PMID:27087841

  20. The gender divide in urban China: Singlehood and assortative mating by age and education

    Directory of Open Access Journals (Sweden)

    Yue Qian

    2014-12-01

    Full Text Available Objective: Chinese media labels highly educated, urban women who are still single in their late 20s as "leftover ladies". We investigate whether indeed highly educated women are less likely to marry than their less-educated counterparts, and how assortative mating patterns by age and education play a role in singleness. Methods: We use data from the urban samples of the Chinese General Social Surveys in the 2000s. In the analysis we calculate marriage rates to examine the likelihood of entry into marriage, and then apply log-linear models to investigate the assortative mating patterns by age and education. Results: We find that as education increases, the likelihood of marriage increases among men but decreases among women, especially among those over age 30. The results from log-linear models reveal that more marriages involve better-educated, older men and less-educated, younger women. Conclusions: We argue that persistent traditional gender roles, accompanied by the rapid rise in women's education, contribute to low marriage rates among older, highly educated women.

  1. Variation in human mate choice: simultaneously investigating heritability, parental influence, sexual imprinting, and assortative mating.

    Science.gov (United States)

    Zietsch, Brendan P; Verweij, Karin J H; Heath, Andrew C; Martin, Nicholas G

    2011-05-01

    Human mate choice is central to individuals' lives and to the evolution of the species, but the basis of variation in mate choice is not well understood. Here we looked at a large community-based sample of twins and their partners and parents ([Formula: see text] individuals) to test for genetic and family environmental influences on mate choice, while controlling for and not controlling for the effects of assortative mating. Key traits were analyzed, including height, body mass index, age, education, income, personality, social attitudes, and religiosity. This revealed near-zero genetic influences on male and female mate choice over all traits and no significant genetic influences on mate choice for any specific trait. A significant family environmental influence was found for the age and income of females' mate choices, possibly reflecting parental influence over mating decisions. We also tested for evidence of sexual imprinting, where individuals acquire mate-choice criteria during development by using their opposite-sex parent as the template of a desirable mate; there was no such effect for any trait. The main discernible pattern of mate choice was assortative mating; we found that partner similarity was due to initial choice rather than convergence and also at least in part to phenotypic matching.

  2. Evidence that avian reovirus σNS is an RNA chaperone: implications for genome segment assortment.

    Science.gov (United States)

    Borodavka, Alexander; Ault, James; Stockley, Peter G; Tuma, Roman

    2015-08-18

    Reoviruses are important human, animal and plant pathogens having 10-12 segments of double-stranded genomic RNA. The mechanisms controlling the assortment and packaging of genomic segments in these viruses, remain poorly understood. RNA-protein and RNA-RNA interactions between viral genomic segment precursors have been implicated in the process. While non-structural viral RNA-binding proteins, such as avian reovirus σNS, are essential for virus replication, the mechanism by which they assist packaging is unclear. Here we demonstrate that σNS assembles into stable elongated hexamers in vitro, which bind single-stranded nucleic acids with high affinity, but little sequence specificity. Using ensemble and single molecule fluorescence spectroscopy, we show that σNS also binds to a partially double-stranded RNA, resulting in gradual helix unwinding. The hexamer can bind multiple RNA molecules and exhibits strand-annealing activity, thus mediating conversion of metastable, intramolecular stem-loops into more stable heteroduplexes. We demonstrate that the ARV σNS acts as an RNA chaperone facilitating specific RNA-RNA interactions between genomic precursors during segment assortment and packaging.

  3. Extended inclusive fitness theory: synergy and assortment drives the evolutionary dynamics in biology and economics.

    Science.gov (United States)

    Jaffe, Klaus

    2016-01-01

    W.D. Hamilton's Inclusive Fitness Theory explains the conditions that favor the emergence and maintenance of social cooperation. Today we know that these include direct and indirect benefits an agent obtains by its actions, and through interactions with kin and with genetically unrelated individuals. That is, in addition to kin-selection, assortation or homophily, and social synergies drive the evolution of cooperation. An Extended Inclusive Fitness Theory (EIFT) synthesizes the natural selection forces acting on biological evolution and on human economic interactions by assuming that natural selection driven by inclusive fitness produces agents with utility functions that exploit assortation and synergistic opportunities. This formulation allows to estimate sustainable cost/benefit threshold ratios of cooperation among organisms and/or economic agents, using existent analytical tools, illuminating our understanding of the dynamic nature of society, the evolution of cooperation among kin and non-kin, inter-specific cooperation, co-evolution, symbioses, division of labor and social synergies. EIFT helps to promote an interdisciplinary cross fertilization of the understanding of synergy by, for example, allowing to describe the role for division of labor in the emergence of social synergies, providing an integrated framework for the study of both, biological evolution of social behavior and economic market dynamics. Another example is a bio-economic understanding of the motivations of terrorists, which identifies different forms of terrorism.

  4. Assimilative and non-assimilative color spreading in the watercolor configuration

    Directory of Open Access Journals (Sweden)

    Eiji eKimura

    2014-09-01

    Full Text Available A colored line flanking a darker contour will appear to spread its color onto an area enclosed by the line (watercolor effect. The watercolor effect has been characterized as an assimilative effect, but non-assimilative color spreading has also been demonstrated in the same spatial configuration; e.g., when a black inner contour (IC is paired with a blue outer contour (OC, yellow color spreading can be observed. To elucidate visual mechanisms underlying these different color spreading effects, this study investigated the effects of luminance ratio between the double contours on the induced color by systematically manipulating the IC and OC luminances (Experiment 1 as well as the background luminance (Experiment 2. The results showed that the luminance conditions suitable for assimilative and non-assimilative color spreading were nearly opposite. When the Weber contrast of the IC to the background luminances (IC contrast was smaller than that of the OC (OC contrast, the induced color became similar to the IC color (assimilative spreading. In contrast, when the OC contrast was smaller than or equal to the IC contrast, the induced color became yellow (non-assimilative spreading. Extending these findings, Experiment 3 showed that bilateral color spreading, e.g., assimilative spreading on one side and non-assimilative spreading on the other side, can also be observed in the watercolor configuration. These results suggest that the assimilative and non-assimilative spreading were mediated by different visual mechanisms. The properties of the assimilative spreading are consistent with the model proposed to account for neon color spreading [Grossberg, S. & Mingolla, E. (1985 Percept. Psychophys., 38, 141-171] and extended for the watercolor effect [Pinna, B., & Grossberg, S. (2005 J. Opt. Soc. Am. A, 22, 2207-2221]. However, the present results suggest that additional mechanisms are needed to account for the non-assimilative color spreading.

  5. Scalable sequential data assimilation with the Parallel Data Assimilation Framework PDAF

    OpenAIRE

    Nerger, Lars; Hiller, Wolfgang; Schröter, Jens

    2011-01-01

    Data assimilation applications with high-dimensional numerical models exhibit extreme requirements on computational resources. Good scalability of the assimilation system is necessary to make these applications feasible. Sequential data assimilation methods based on ensemble forecasts, like ensemble-based Kalman filters, provide such good scalability, because the forecast of each ensemble member can be performed independently. However, this parallelism has to be combined with the paralleli...

  6. IS ASSIMILATION THEORY DEAD? THE EFFECT OF ASSIMILATION ON ADOLESCENT WELL-BEING

    OpenAIRE

    Greenman, Emily; Xie, Yu

    2008-01-01

    The relationship between assimilation and the well-being of immigrant children has been the focus of debate in the recent sociological literature. Much of this work has questioned whether classical theories of immigrant adaptation, which assumed assimilation to be an integral part of the process of upward mobility for immigrants, are still applicable to today’s immigrant children. This study reevaluates the applicability of classical assimilation theory with a comprehensive empirical assessme...

  7. Extending NEMO for ensemble data assimilation on supercomputers with the parallel data assimilation framework PDAF

    OpenAIRE

    Nerger, Lars; Kirchgessner, Paul

    2014-01-01

    The NEMO model is a state-of-the-art ocean circulation model. For data assimilation applications with ensemble Kalman filters like the SEEK filter, e.g. for operational ocean forecasting, NEMO is typically run separately from the assimilation algorithm. Thus, NEMO is used to generate a set of restart files on disks that hold the ensemble of model forecasts providing the error covariance matrix information for the ensemble Kalman filter. These files need to be read by a separate assimilation p...

  8. THE SOCIAL CONTEXT OF ASSIMILATION: TESTING IMPLICATIONS OF SEGMENTED ASSIMILATION THEORY*

    OpenAIRE

    Xie, Yu; Greenman, Emily

    2011-01-01

    Segmented assimilation theory has been a popular explanation for the diverse experiences of assimilation among new waves of immigrants and their children. While the theory has been interpreted in many different ways, we emphasize its implications for the important role of social context: both processes and consequences of assimilation should depend on the local social context in which immigrants are embedded. We derive empirically falsifiable hypotheses about the interaction effects between s...

  9. Assimilative and non-assimilative color spreading in the watercolor configuration.

    Science.gov (United States)

    Kimura, Eiji; Kuroki, Mikako

    2014-01-01

    A colored line flanking a darker contour will appear to spread its color onto an area enclosed by the line (watercolor effect). The watercolor effect has been characterized as an assimilative effect, but non-assimilative color spreading has also been demonstrated in the same spatial configuration; e.g., when a black inner contour (IC) is paired with a blue outer contour (OC), yellow color spreading can be observed. To elucidate visual mechanisms underlying these different color spreading effects, this study investigated the effects of luminance ratio between the double contours on the induced color by systematically manipulating the IC and the OC luminance (Experiment 1) as well as the background luminance (Experiment 2). The results showed that the luminance conditions suitable for assimilative and non-assimilative color spreading were nearly opposite. When the Weber contrast of the IC to the background luminance (IC contrast) was smaller in size than that of the OC (OC contrast), the induced color became similar to the IC color (assimilative spreading). In contrast, when the OC contrast was smaller than or equal to the IC contrast, the induced color became yellow (non-assimilative spreading). Extending these findings, Experiment 3 showed that bilateral color spreading, i.e., assimilative spreading on one side and non-assimilative spreading on the other side, can also be observed in the watercolor configuration. These results suggest that the assimilative and the non-assimilative spreading were mediated by different visual mechanisms. The properties of the assimilative spreading are consistent with the model proposed to account for neon color spreading (Grossberg and Mingolla, 1985) and extended for the watercolor effect (Pinna and Grossberg, 2005). However, the present results suggest that additional mechanisms are needed to account for the non-assimilative color spreading. PMID:25285074

  10. Compensation for complete assimilation in speech perception: The case of Korean labial-to-velar assimilation

    OpenAIRE

    Mitterer, H.; Kim, S.; Cho, T.

    2013-01-01

    In connected speech, phonological assimilation to neighboring words can lead to pronunciation variants (e.g., 'garden bench'→ "gardem bench"). A large body of literature suggests that listeners use the phonetic context to reconstruct the intended word for assimilation types that often lead to incomplete assimilations (e.g., a pronunciation of "garden" that carries cues for both a labial [m] and an alveolar [n]). In the current paper, we show that a similar context effect is observed for an as...

  11. ITERATIVE ALGORITHMS FOR DATA ASSIMILATION PROBLEMS

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    Iterative algorithms for solving the data assimilation problems are considered, based on the main and adjoint equations. Spectral properties of the control operators of the problem are studied, the iterative algorithms are justified.

  12. Assimilation of ammonia in Paracoccus denitrificans.

    Science.gov (United States)

    Mikes, V; Chválová, H; Mátlová, L

    1991-01-01

    Two pathways serve for assimilation of ammonia in Paracoccus denitrificans. Glutamate dehydrogenase (NADP+) catalyzes the assimilation at a high NH4+ concentration. If nitrate serves as the nitrogen source, glutamate is synthesized by glutamate-ammonia ligase and glutamate synthase (NADPH). At a very low NH4+ concentration, all three enzymes are synthesized simultaneously. No direct relationship exists between glutamate dehydrogenase (NADP+) and glutamate-ammonia ligase in P. denitrificans, while the glutamate synthase (NADPH) activity changes in parallel with that of the latter enzyme. Ammonia does not influence the induction or repression of glutamate dehydrogenase (NADP+). The inner concentration of metabolites indicates a possible repression of glutamate dehydrogenase (NADP+) by the high concentration of glutamine or its metabolic products as in the case when NH4+ is formed by assimilative nitrate reduction. No direct effect of the intermediates of nitrate assimilation on the synthesis of glutamate dehydrogenase (NADP+) was observed. PMID:1688163

  13. Management of potential transuranium assimilation cases

    International Nuclear Information System (INIS)

    This review deals primarily with the duties of Health Protection personnel assigned to Savannah River's operatig facilities - as opposed to the role of bioassay and dosimetry specialists - in handling potential transuranium assimilation cases

  14. ERP ASSIMILATION: AN END-USER APPROACH

    Directory of Open Access Journals (Sweden)

    Hurbean Luminita

    2013-07-01

    The paper discusses the ERP adoption based on the IT assimilation theory. The ERP lifecycle is associated with the IT assimilation steps. We propose a distribution of these steps along the lifecycle. Derived from the findings in the reviewed literature we will focus the cultural factors, in particular those related to the end-users (determined as a major impact factor in our previous study: Negovan et al., 2011. Our empirical study is centred on the end-users perspective and it tries to determine if and how their behaviour affects the achievement of the ERP assimilation steps. The paper reasons that organizations that understand the IT assimilation steps correlated to the ERP implementation critical factors are more likely to implement and use ERP successfully.

  15. No evidence for size-assortative mating in the wild despite mutual mate choice in sex-role-reversed pipefishes.

    Science.gov (United States)

    Mobley, Kenyon B; Abou Chakra, Maria; Jones, Adam G

    2014-01-01

    Size-assortative mating is a nonrandom association of body size between members of mating pairs and is expected to be common in species with mutual preferences for body size. In this study, we investigated whether there is direct evidence for size-assortative mating in two species of pipefishes, Syngnathus floridae and S. typhle, that share the characteristics of male pregnancy, sex-role reversal, and a polygynandrous mating system. We take advantage of microsatellite-based "genetic-capture" techniques to match wild-caught females with female genotypes reconstructed from broods of pregnant males and use these data to explore patterns of size-assortative mating in these species. We also develop a simulation model to explore how positive, negative, and antagonistic preferences of each sex for body size affect size-assortative mating. Contrary to expectations, we were unable to find any evidence of size-assortative mating in either species at different geographic locations or at different sampling times. Furthermore, two traits that potentially confer a fitness advantage in terms of reproductive success, female mating order and number of eggs transferred per female, do not affect pairing patterns in the wild. Results from model simulations demonstrate that strong mating preferences are unlikely to explain the observed patterns of mating in the studied populations. Our study shows that individual mating preferences, as ascertained by laboratory-based mating trials, can be decoupled from realized patterns of mating in the wild, and therefore, field studies are also necessary to determine actual patterns of mate choice in nature. We conclude that this disconnect between preferences and assortative mating is likely due to ecological constraints and multiple mating that may limit mate choice in natural populations. PMID:24455162

  16. Wage and occupational assimilation by skill level

    OpenAIRE

    Alcobendas, Miguel Angel; Rodríguez-Planas, Núria; Vegas, Raquel

    2012-01-01

    While much of the literature on immigrants' assimilation has focused on countries with a large tradition of receiving immigrants and with flexible labor markets, very little is known on how immigrants adjust to other types of host economies. With its severe dual labor market, and an unprecedented immigration boom, Spain presents a quite unique experience to analyze immigrations' assimilation process. Using alternative datasets and methodologies, this paper provides evidence of a differential ...

  17. Effective assimilation of global precipitation: simulation experiments

    OpenAIRE

    Lien, Guo-Yuan; Kalnay, Eugenia; Miyoshi, Takemasa

    2013-01-01

    Past attempts to assimilate precipitation by nudging or variational methods have succeeded in forcing the model precipitation to be close to the observed values. However, the model forecasts tend to lose their additional skill after a few forecast hours. In this study, a local ensemble transform Kalman filter (LETKF) is used to effectively assimilate precipitation by allowing ensemble members with better precipitation to receive higher weights in the analysis. In addition, two other changes i...

  18. On errors in meteorological data assimilation

    OpenAIRE

    Lindskog, Magnus

    2007-01-01

    Data assimilation in Numerical Weather Prediction (NWP) optimally blends observations with atmospheric model data in order to obtain the best possible initial state for an atmospheric model prediction. Specification of error characteristics is an important part of data assimilation. This thesis is concerned with representation of background error standard deviations, with handling of observations, and with observation error characteristics. The research includes both the study of basic assimi...

  19. Migration, Friendship Ties, and Cultural Assimilation

    OpenAIRE

    Facchini, Giovanni; Patacchini, Eleonora; Steinhardt, Max

    2014-01-01

    In this paper we contribute to the analysis of the assimilation process of migrants by analyzing the extent to which friendship with natives can be seen as a measure of cultural assimilation and investigating the formation of social ties in the host country. Using novel information from the German Socio-Economic Panel, we find that migrants with a German friend are more similar to natives than those without a local companion along several important dimensions, including concerns about the eco...

  20. Evidence of New Immigrant Assimilation in Canada

    OpenAIRE

    Mary L. Grant

    1999-01-01

    Previous studies of the labour market experience of male immigrants to Canada have uncovered two disturbing trends: declining entry earnings for successive new immigrant cohorts and low assimilation rates. These findings suggest that many of these cohorts may never assimilate. The 1991 Census provides a first look at the immigrant cohorts arriving in the 1980s. These immigrants appear to avoid the plight of their predecessors; entry earnings have stopped falling, and those immigrants arriving...

  1. Employment Assimilation of Immigrants in the Netherlands

    OpenAIRE

    Zorlu, Aslan; Hartog, Joop

    2008-01-01

    This discussion Paper led to a publication in International Journal of Population Research , Vol. 2012, article ID 634276. Using two Dutch labour force surveys, employment assimilation of immigrants is examined. We observe marked differences between immigrants by source country. Non-western immigrants never reach parity with native Dutch. Even second generation immigrants never fully catch up. Caribbean immigrants, who share a colonial history with the Dutch, assimilate relatively quick compa...

  2. Immigrants on Welfare: Assimilation and Benefit Substitution

    OpenAIRE

    Ekhaugen, Tyra

    2005-01-01

    Non-western immigrants in Norway are shown to rely heavily on welfare transfers for several years after immigration. While refugee immigrants assimilate slightly out of welfare, other non-western immigrants assimilate rapidly into welfare. Re-migration is selective for both non-western and western immigrants, insofar as the probability of re-migration correlates negatively with the probability of receiving welfare. We argue that previous studies may have reached biased estimates of welfare as...

  3. The heterogeneity in immigrants unhealthy assimilation

    OpenAIRE

    Barbieri, Paolo Nicola

    2016-01-01

    Immigrants upon their arrival in the United States are in better health condition with respect to their American counterpart however such advantage erodes over time. In this paper, we study the heterogeneity of such unhealthy behaviours assimilation among different arrival cohorts. We focus our analysis on binge drinking and cigarette consumption as a proxy for unhealthy behaviour assimilation by immigrants. Regarding binge drinking we show that more recent immigrant cohorts arriv...

  4. Interethnic Marriages and Economic Assimilation of Immigrants

    OpenAIRE

    Kantarevic, Jasmin

    2004-01-01

    This paper examines the relationship between interethnic marriages and economic assimilation among immigrants in the United States. Two competing hypotheses are evaluated: the productivity hypothesis, according to which immigrants married to native-born spouses assimilate faster than comparable immigrants married to foreign-born spouses because spouses play an integral role in the human capital accumulation of their partners; and the selection hypothesis, according to which the relationship b...

  5. The Acceleration of Immigrant Unhealthy Assimilation

    OpenAIRE

    Giuntella, Osea; Stella, Luca

    2016-01-01

    It is well-known that immigrants tend to be healthier than US natives and that this advantage erodes with time spent in the US. However, we know less about the heterogeneity of these trajectories among arrival cohorts. Recent studies have shown that later arrival cohorts of immigrants have lower entry wages and experience less economic assimilation. In this paper, we investigate whether similar cohort effects can be observed in the weight assimilation of immigrants in the US. Focusing on obes...

  6. The gendered embodiment of shame: Intersections of acquaintance rape, trauma and self-blame in Pompidou posse by Sarah Lotz

    Directory of Open Access Journals (Sweden)

    Jessica Murray

    2014-08-01

    Full Text Available This article offers a feminist literary analysis of the gendered embodiment of shame in Pompidou posse by Sarah Lotz. In this novel, Lotz depicts female characters who are sexually assaulted by acquaintances and the resultant shame and trauma reside in their bodies. I will demonstrate that the embodied shame of these characters is distinctly gendered and that this shapes their attempts to cope with the aftermath of the sexual assaults. A close reading of the text reveals that the characters are exposed to overwhelming social messages of female culpability in a larger context that is rife with misogyny. As a result, they anticipate blame to such an extent that they blame themselves and internalise this blame as shame. By focusing on the bodies of the survivors, Lotz demonstrates the embodiment of shame, but she also suggests a corporeal challenge to silencing. The bodies of these characters speak loudly, albeit sometimes in the halting language of trauma, and they function to alert them to danger, to help them excavate memories that are made inaccessible and to testify to traumatic sexual assault.

  7. Data Assimilation: Making Sense of Earth Observation

    Directory of Open Access Journals (Sweden)

    William Albert Lahoz

    2014-05-01

    Full Text Available Climate change, air quality and environmental degradation are important societal challenges for the 21st Century. These challenges require an intelligent response from society, which in turn requires access to information about the Earth System. This information comes from observations and prior knowledge, the latter typically embodied in a model describing relationships between variables of the Earth System. Data assimilation provides an objective methodology to combine observational and model information to provide an estimate of the most likely state and its uncertainty for the whole Earth System. This approach adds value to the observations – by filling in the spatio-temporal gaps in observations; and to the model – by constraining it with the observations. In this review paper we motivate data assimilation as a methodology to fill in the gaps in observational information; illustrate the data assimilation approach with examples that span a broad range of features of the Earth System (atmosphere, including chemistry; ocean; land surface; and discuss the outlook for data assimilation, including the novel application of data assimilation ideas to observational information obtained using Citizen Science. Ultimately, a strong motivation of data assimilation is the many benefits it provides to users. These include: providing the initial state for weather and air quality forecasts; providing analyses and reanalyses for studying the Earth System; evaluating observations, instruments and models; assessing the relative value of elements of the Global Observing System (GOS; and assessing the added value of future additions to the GOS.

  8. Assessing Immigrant Assimilation: New Empirical and Theoretical Challenges

    OpenAIRE

    Waters, Mary; Jimenez, Tomas R.

    2005-01-01

    This review examines research on the assimilation of immigrant groups. We review research on four primary benchmarks of assimilation: socioeconomic status, spatial concentration, language assimilation, and intermarriage. The existing literature shows that today's immigrants are largely assimilating into American society along each of these dimensions. This review also considers directions for future research on the assimilation of immigrant groups in new southern and midwestern gateways and h...

  9. Assimilation of the Microwave Limb Sounder Radiances

    Science.gov (United States)

    Wargan, K.; Read, W.; Livesey, N.; Wagner, P.; Nguyen. H.; Pawson, S.

    2012-01-01

    It has been shown that the assimilation of limb-sounder data can significantly improve the representation of ozone in NASA's GEOS Data Assimilation Systems (GEOS-DAS), particularly in the stratosphere. The studies conducted so far utilized retrieved data from the MIPAS, POAM, ILAS and EOS Microwave Limb Sounder (EOS MLS) instruments. Direct assimilation of the radiance data can be seen as the natural next step to those studies. The motivation behind working with radiances is twofold. First, retrieval algorithms use a priori data which are either climatological or are obtained from previous analyses. This introduces additional uncertainty and, in some cases, may lead to "self-contamination"- when the a priori is taken from the same assimilation system in which subsequently ingests the retrieved observations. Second, radiances can be available in near real time thus providing an opportunity for operational assimilation, which could help improve the use of infrared radiance instruments from operational satellite instruments. In this presentation we summarize our ongoing work on an implementation of the assimilation of EOS MLS radiances into the GEOS-5 DAS. This work focuses on assimilation of band 7 brightness temperatures which are sensitive to ozone. Our implementation uses the MLS Callable Forward Model developed by the MLS team at NASA JPL as the observation operator. We will describe our approach and recent results which are not yet final. In particular, we will demonstrate that this approach has a potential to improve the vertical structure of ozone in the lower tropical stratosphere as compared with the retrieved MLS product. We will discuss the computational efficiency of this implementation.

  10. The social context of assimilation: testing implications of segmented assimilation theory.

    Science.gov (United States)

    Xie, Yu; Greenman, Emily

    2011-05-01

    Segmented assimilation theory has been a popular explanation for the diverse experiences of assimilation among new waves of immigrants and their children. While the theory has been interpreted in many different ways, we emphasize its implications for the important role of social context: both processes and consequences of assimilation should depend on the local social context in which immigrants are embedded. We derive empirically falsifiable hypotheses about the interaction effects between social context and assimilation on immigrant children's well-being. We then test the hypotheses using data from the National Longitudinal Study of Adolescent Health. Our empirical analyses yield two main findings. First, for immigrant adolescents living in non-poverty neighborhoods, we find assimilation to be positively associated with educational achievement and psychological well-being but also positively associated with at-risk behavior. Second, there is little empirical evidence supporting our hypotheses derived from segmented assimilation theory. We interpret these results to mean that future research would be more fruitful focusing on differential processes of assimilation rather than differential consequences of assimilation. PMID:21572546

  11. Efficient Methods to Assimilate Satellite Retrievals Based on Information Content. Part 2; Suboptimal Retrieval Assimilation

    Science.gov (United States)

    Joiner, J.; Dee, D. P.

    1998-01-01

    One of the outstanding problems in data assimilation has been and continues to be how best to utilize satellite data while balancing the tradeoff between accuracy and computational cost. A number of weather prediction centers have recently achieved remarkable success in improving their forecast skill by changing the method by which satellite data are assimilated into the forecast model from the traditional approach of assimilating retrievals to the direct assimilation of radiances in a variational framework. The operational implementation of such a substantial change in methodology involves a great number of technical details, e.g., pertaining to quality control procedures, systematic error correction techniques, and tuning of the statistical parameters in the analysis algorithm. Although there are clear theoretical advantages to the direct radiance assimilation approach, it is not obvious at all to what extent the improvements that have been obtained so far can be attributed to the change in methodology, or to various technical aspects of the implementation. The issue is of interest because retrieval assimilation retains many practical and logistical advantages which may become even more significant in the near future when increasingly high-volume data sources become available. The central question we address here is: how much improvement can we expect from assimilating radiances rather than retrievals, all other things being equal? We compare the two approaches in a simplified one-dimensional theoretical framework, in which problems related to quality control and systematic error correction are conveniently absent. By assuming a perfect radiative transfer model and perfect knowledge of radiance and background error covariances, we are able to formulate a nonlinear local error analysis for each assimilation method. Direct radiance assimilation is optimal in this idealized context, while the traditional method of assimilating retrievals is suboptimal because it

  12. Variation in sexual dimorphism and assortative mating do not predict genetic divergence in the sexually dimorphic Goodeid fish Girardinichthys multiradiatus

    Institute of Scientific and Technical Information of China (English)

    C.MAC(I)AS GARCIA; G SMITH; C.GONZ(A)LEZ ZUARTH; J.A.GRAVES; M.G.RITCHIE

    2012-01-01

    Sexual dimorphism is often used as a proxy for the intensity of sexual selection in comparative studies of sexual selection and diversification.The Mexican Goodeinae are a group of livebearing freshwater fishes with large variation between species in sexual dimorphism in body shape.Previously we found an association between variation in morphological sexual dimorphism between species and the amount of gene flow within populations in the Goodeinae.Here we have examined if morphological differentiation within a single dimorphic species is related to assortative mating or gene flow between populations.In the Amarillo fish Girardinichthys multiradiatus studies have shown that exaggerated male fins are targets of female preferences.We find that populations of the species differ in the level of sexual dimorphism displayed due to faster evolution of differences in male than female morphology.However,this does not predict variation in assortative mating tests in the laboratory; in fact differences in male morphology are negatively correlated with assortative mating.Microsatellite markers reveal significant genetic differences between populations.However,gene flow is not predicted by either morphological differences or assortative mating.Rather,it demonstrates a pattern of isolation by distance with greater differentiation between watersheds.We discuss the caveats of predicting behavioural and genetic divergence from so-called proxies of sexual selection.

  13. Variation in sexual dimorphism and assortative mating do not predict genetic divergence in the sexually dimorphic Goodeid fish Girardinichthys multiradiatus

    Directory of Open Access Journals (Sweden)

    C.MACÍAS GARCIA, G.SMITH, C.GONZÁLEZ ZUARTH, J.A. GRAVES,M.G.RITCHIE

    2012-06-01

    Full Text Available Sexual dimorphism is often used as a proxy for the intensity of sexual selection in comparative studies of sexual selection and diversification. The Mexican Goodeinae are a group of livebearing freshwater fishes with large variation between species in sexual dimorphism in body shape. Previously we found an association between variation in morphological sexual dimorphism between species and the amount of gene flow within populations in the Goodeinae. Here we have examined if morphological differentiation within a single dimorphic species is related to assortative mating or gene flow between populations. In the Amarillo fish Girardinichthys multiradiatus studies have shown that exaggerated male fins are targets of female preferences. We find that populations of the species differ in the level of sexual dimorphism displayed due to faster evolution of differences in male than female morphology. However, this does not predict variation in assortative mating tests in the laboratory; in fact differences in male morphology are negatively correlated with assortative mating. Microsatellite markers reveal significant genetic differences between populations. However, gene flow is not predicted by either morphological differences or assortative mating. Rather, it demonstrates a pattern of isolation by distance with greater differentiation between watersheds. We discuss the caveats of predicting behavioural and genetic divergence from so-called proxies of sexual selection [Current Zoology 58 (3: 437-449, 2012].

  14. Imposing Nonlinear Constraints When Estimating Genetic and Cultural Transmission Under Assortative Mating: A Simulation Study Using Mx and BUGS

    NARCIS (Netherlands)

    Berg, van den Stephanie M.

    2009-01-01

    Modeling both genetic and cultural transmission in parent-offspring data in the presence of phenotypic assortment requires the imposition of nonlinear constraints. This article reports a simulation study that determined how well the structural equation modeling software package Mx and the Bayesian-o

  15. Organizing Products with Complements versus Substitutes: Effects on Store Preferences as a Function of Effort and Assortment Perceptions

    NARCIS (Netherlands)

    Diehl, K.; Herpen, van E.; Lamberton, C.

    2015-01-01

    Retailers often organize at least part of their assortment by displaying complementary products from different product categories together (e.g., a pair of pants with a shirt) rather than grouping items by product type (e.g., a pair of pants with other pants). However, little is known about how reta

  16. Accuracy in estimation of timber assortments and stem distribution - A comparison of airborne and terrestrial laser scanning techniques

    Science.gov (United States)

    Kankare, Ville; Vauhkonen, Jari; Tanhuanpää, Topi; Holopainen, Markus; Vastaranta, Mikko; Joensuu, Marianna; Krooks, Anssi; Hyyppä, Juha; Hyyppä, Hannu; Alho, Petteri; Viitala, Risto

    2014-11-01

    Detailed information about timber assortments and diameter distributions is required in forest management. Forest owners can make better decisions concerning the timing of timber sales and forest companies can utilize more detailed information to optimize their wood supply chain from forest to factory. The objective here was to compare the accuracies of high-density laser scanning techniques for the estimation of tree-level diameter distribution and timber assortments. We also introduce a method that utilizes a combination of airborne and terrestrial laser scanning in timber assortment estimation. The study was conducted in Evo, Finland. Harvester measurements were used as a reference for 144 trees within a single clear-cut stand. The results showed that accurate tree-level timber assortments and diameter distributions can be obtained, using terrestrial laser scanning (TLS) or a combination of TLS and airborne laser scanning (ALS). Saw log volumes were estimated with higher accuracy than pulpwood volumes. The saw log volumes were estimated with relative root-mean-squared errors of 17.5% and 16.8% with TLS and a combination of TLS and ALS, respectively. The respective accuracies for pulpwood were 60.1% and 59.3%. The differences in the bucking method used also caused some large errors. In addition, tree quality factors highly affected the bucking accuracy, especially with pulpwood volume.

  17. A phylogenetic analysis of body size evolution in the Anolis roquet group (Sauria: Iguanidae): character displacement or size assortment?

    Science.gov (United States)

    Giannasi, N; Thorpe, R S; Malhotra, A

    2000-02-01

    The important role that competition plays in structuring communities is well documented; however, the role of competition in an evolutionary context remains unclear. Evolutionary investigations into the role of competition have often focused on the process of character displacement, and a good example of this is the evolution of body size in the Anolis lizards of the Caribbean islands. Previous work on the A. roquet species group has taken a phylogenetic approach and concluded that patterns of body size differences are not caused by character displacement but are a result of size assortment. Using a phylogenetic reconstruction based on the sequence of the cytochrome b gene (cyt-b) and ancestral character-state reconstruction methods, we investigated the roles of character displacement and size assortment. Our results indicated that size assortment alone was insufficient to explain the observed patterns of body size differences. Furthermore, we found that change in body size was associated with a change in allopatry/sympatry, thus supporting the character-displacement hypothesis. We conclude that patterns of body size differences in the A. roquet species group appear to be the result of a combination of character displacement and size assortment because character displacement was only found to be possible on three occasions.

  18. Parasite-stress promotes in-group assortative sociality: the cases of strong family ties and heightened religiosity.

    Science.gov (United States)

    Fincher, Corey L; Thornhill, Randy

    2012-04-01

    Throughout the world people differ in the magnitude with which they value strong family ties or heightened religiosity. We propose that this cross-cultural variation is a result of a contingent psychological adaptation that facilitates in-group assortative sociality in the face of high levels of parasite-stress while devaluing in-group assortative sociality in areas with low levels of parasite-stress. This is because in-group assortative sociality is more important for the avoidance of infection from novel parasites and for the management of infection in regions with high levels of parasite-stress compared with regions of low infectious disease stress. We examined this hypothesis by testing the predictions that there would be a positive association between parasite-stress and strength of family ties or religiosity. We conducted this study by comparing among nations and among states in the United States of America. We found for both the international and the interstate analyses that in-group assortative sociality was positively associated with parasite-stress. This was true when controlling for potentially confounding factors such as human freedom and economic development. The findings support the parasite-stress theory of sociality, that is, the proposal that parasite-stress is central to the evolution of social life in humans and other animals.

  19. Uranium recovery from assorted laboratory organic waste solutions using centrifugal contractors

    International Nuclear Information System (INIS)

    Countercurrent extraction runs, carried out in our laboratory for the evaluation studies of N,N-dihexyloctanamide (DHOA) as an alternative of tributyl phosphate (TBP) for spent fuel reprocessing, have led to generation of large volumes of organic wastes containing varying amounts of uranium. It was desirable to recover uranium from such waste solutions prior to the disposal of organic waste solutions. Even though, batch stripping can be used for this purpose, it may take several days to achieve the desired goal. In this context, the centrifugal contactors appear attractive due to high liquid through-put, which may simplify the uranium recovery process. Uranium recovery studies from assorted organic waste solutions were therefore carried out using centrifugal contactors

  20. MODERNIZATION OF ASSORTMENT OF TABLE GRAPES FOR FARMERS AND CROFT VITICULTURE

    Directory of Open Access Journals (Sweden)

    Troshin L. P.

    2014-01-01

    Full Text Available The article highlights the issues of improving the assortment of table grape plantations for use in the farms and croft forms of management. Brief presentation of results of the five-year study of 12 table grape varieties in industrial environments for their cultivation: in the OAO AF of "Juznaja", OOO "Phanagoria-Agro" training field "Kuban" and branches of the Department of Viticulture Kuban State Agricultural University: Citrine, Helios, Bogatyanovsky, Anthracite, Dolgogdanij, Preobragenije, Academic K, Rochefort K, Libya K, Kubattik, Nizina and Chrysolite. These varieties are the basis of modern conveyor of table varieties and are recommended for introduction in the State register of breeding achievements of the Russian Federation in all regions of our country

  1. Intergenerational income mobility – top incomes and assortative mating in Denmark

    DEFF Research Database (Denmark)

    Hussain, M. Azhar; Bonke, Jens; Munk, Martin D.

    2011-01-01

    , in particular, when including capital income in the total income. Also we find the marriage match has a stronger impact on the family-to-family income transfer in the top of the income distribution where the daughter marries a man more like her father than herself. The highest persistence, however, is between......This article investigates intergenerational income mobility among top-income people in Denmark focusing on the impact of assortative mating. Earnings and capital income are the variables of interest included in the analyzes testing the hypothesis that both wealth and social heritage are transferred...... from rich parents to their children. Using administrative registers allow us to look at small fractions of the populations, i.e. dynasties, and to distinguish between sons and daughters and to observe their eventual spouses’ incomes. We find that intergenerational mobility is lower in the top...

  2. The Analysis Of The Correlations And Regressions Between Some Characters On A Wheat Isogenic Varities Assortment

    Science.gov (United States)

    Păniţă, Ovidiu

    2015-09-01

    In the years 2012-2014 on Banu-Maracine DRS there were tested an assortment of 25 isogenic lines of wheat (Triticum aestivum ssp.vulgare), the analyzed characters being the number of seeds/spike, seeds weight/spike (g), no. of spikes/m2, weight of a thousand seeds (WTS) (g) and no. of emerged plants/m2. Based on recorded data and statistical processing of those, they were identified a numbers of links between these characters. Also available regression models were identified between some of the studied characters. Based on component analysis, no. of seeds/spike and seeds weight/spike are components that influence in excess of 88% variance analysis, a total of seven genotypes with positive scores for both factors.

  3. Knocking out multigene redundancies via cycles of sexual assortment and fluorescence selection.

    Science.gov (United States)

    Suzuki, Yo; St Onge, Robert P; Mani, Ramamurthy; King, Oliver D; Heilbut, Adrian; Labunskyy, Vyacheslav M; Chen, Weidong; Pham, Linda; Zhang, Lan V; Tong, Amy H Y; Nislow, Corey; Giaever, Guri; Gladyshev, Vadim N; Vidal, Marc; Schow, Peter; Lehár, Joseph; Roth, Frederick P

    2011-02-01

    Phenotypes that might otherwise reveal a gene's function can be obscured by genes with overlapping function. This phenomenon is best known within gene families, in which an important shared function may only be revealed by mutating all family members. Here we describe the 'green monster' technology that enables precise deletion of many genes. In this method, a population of deletion strains with each deletion marked by an inducible green fluorescent protein reporter gene, is subjected to repeated rounds of mating, meiosis and flow-cytometric enrichment. This results in the aggregation of multiple deletion loci in single cells. The green monster strategy is potentially applicable to assembling other engineered alterations in any species with sex or alternative means of allelic assortment. To test the technology, we generated a single broadly drug-sensitive strain of Saccharomyces cerevisiae bearing precise deletions of all 16 ATP-binding cassette transporters within clades associated with multidrug resistance.

  4. The structure of a food product assortment modulates the effect of providing choice on food intake.

    Science.gov (United States)

    Parizel, Odile; Sulmont-Rossé, Claire; Fromentin, Gilles; Delarue, Julien; Labouré, Hélène; Benamouzig, Robert; Marsset-Baglieri, Agnès

    2016-09-01

    Several authors showed that providing choice may increase food liking and food intake. However, the impact of choice may be modulated by assortment's characteristics, such as the number of alternatives or their dissimilarity. The present study compared the impact of choice on food liking and intake under the two following conditions: (1) when choosing a product to consume from among similar products versus dissimilar products; and (2) when choosing a product to consume from among pleasant products versus unpleasant products. Two experiments were carried out using the same design: the "apple puree" experiment (n = 80), where the volunteers choose from among similar products (apple purees varying in texture) and the "dessert" experiment (n = 80), where the volunteers choose from among dissimilar products (fruit dessert, dairy dessert, custard, pudding). During the first session, participants rated their liking for 12 products (apples purees or desserts). Then the participants were divided into a "pleasant" group (n = 40) in which volunteers were assigned three pleasant products, and an "unpleasant" group (n = 40) in which volunteers were assigned three unpleasant products. Finally, all of the volunteers participated in a choice session - volunteers were presented with their three assigned products and asked to choose one of the products, and a no-choice session - volunteers were served with one product that was randomly selected from among their three assigned products. Providing choice led to an increase in food liking in both experiments and an increase in food intake only for the desserts, namely only when the volunteers chose the product to consume from among "not too similar" alternatives. No effect of assortment's pleasantness was observed. PMID:26606886

  5. Association between autozygosity and major depression: stratification due to religious assortment.

    Science.gov (United States)

    Abdellaoui, Abdel; Hottenga, Jouke-Jan; Xiao, Xiangjun; Scheet, Paul; Ehli, Erik A; Davies, Gareth E; Hudziak, James J; Smit, Dirk J A; Bartels, Meike; Willemsen, Gonneke; Brooks, Andrew; Sullivan, Patrick F; Smit, Johannes H; de Geus, Eco J; Penninx, Brenda W J H; Boomsma, Dorret I

    2013-11-01

    The effects of inbreeding on the health of offspring can be studied by measuring genome-wide autozygosity as the proportion of the genome in runs of homozygosity (F roh) and relate F roh to outcomes such as psychiatric phenotypes. To successfully conduct these studies, the main patterns of variation for genome-wide autozygosity between and within populations should be well understood and accounted for. Within population variation was investigated in the Dutch population by comparing autozygosity between religious and non-religious groups. The Netherlands have a history of societal segregation and assortment based on religious affiliation, which may have increased parental relatedness within religious groups. Religion has been associated with several psychiatric phenotypes, such as major depressive disorder (MDD). We investigated whether there is an association between autozygosity and MDD, and the extent to which this association can be explained by religious affiliation. All F roh analyses included adjustment for ancestry-informative principal components (PCs) and geographic factors. Religious affiliation was significantly associated with autozygosity, showing that F roh has the ability to capture within population differences that are not captured by ancestry-informative PCs or geographic factors. The non-religious group had significantly lower F roh values and significantly more MDD cases, leading to a nominally significant negative association between autozygosity and depression. After accounting for religious affiliation, MDD was not associated with F roh, indicating that the relation between MDD and inbreeding was due to stratification. This study shows how past religious assortment and recent secularization can have genetic consequences in a relatively small country. This warrants accounting for the historical social context and its effects on genetic variation in association studies on psychiatric and other related traits.

  6. The structure of a food product assortment modulates the effect of providing choice on food intake.

    Science.gov (United States)

    Parizel, Odile; Sulmont-Rossé, Claire; Fromentin, Gilles; Delarue, Julien; Labouré, Hélène; Benamouzig, Robert; Marsset-Baglieri, Agnès

    2016-09-01

    Several authors showed that providing choice may increase food liking and food intake. However, the impact of choice may be modulated by assortment's characteristics, such as the number of alternatives or their dissimilarity. The present study compared the impact of choice on food liking and intake under the two following conditions: (1) when choosing a product to consume from among similar products versus dissimilar products; and (2) when choosing a product to consume from among pleasant products versus unpleasant products. Two experiments were carried out using the same design: the "apple puree" experiment (n = 80), where the volunteers choose from among similar products (apple purees varying in texture) and the "dessert" experiment (n = 80), where the volunteers choose from among dissimilar products (fruit dessert, dairy dessert, custard, pudding). During the first session, participants rated their liking for 12 products (apples purees or desserts). Then the participants were divided into a "pleasant" group (n = 40) in which volunteers were assigned three pleasant products, and an "unpleasant" group (n = 40) in which volunteers were assigned three unpleasant products. Finally, all of the volunteers participated in a choice session - volunteers were presented with their three assigned products and asked to choose one of the products, and a no-choice session - volunteers were served with one product that was randomly selected from among their three assigned products. Providing choice led to an increase in food liking in both experiments and an increase in food intake only for the desserts, namely only when the volunteers chose the product to consume from among "not too similar" alternatives. No effect of assortment's pleasantness was observed.

  7. CHOLESTEROL ASSIMILATION BY COMMERCIAL YOGHURT STARTER CULTURES

    Directory of Open Access Journals (Sweden)

    Małgorzata Ziarno

    2007-03-01

    Full Text Available The ability to in vitro cholesterol level reduction in laboratory media has been shown for numerous strains of lactic acid bacteria, but not for all strains of lactic bacteria used in the dairy industry. The aim of this work was the determination of the ability of selected thermophilic lactic acid bacteria to cholesterol assimilation during 24 h culture in MRS broth. Commercial starter cultures showed various ability to cholesterol assimilation from laboratory medium. In case of starter cultures used for production of traditional yoghurt, consisting of Streptococcus salivarius subsp. thermophilus and Lactobacillus delbrueckii subsp. bulgaricus, the quantity of assimilated cholesterol did not exceed 27% of its initial contents (0.7 g in 1 dm3. Starter cultures used for bioyoghurt production, containing also probiotic strains (came from Lactobacillus acidophilus species or Bifidobacterium genus assimilated from almost 18% to over 38% of cholesterol. For one monoculture of Lb. acidophilus, cholesterol assimilation ability of 49-55% was observed, despite that the number of bacterial cells in this culture was not different from number of bacteria in other cultures.

  8. Getting Acquainted with OPML

    CERN Document Server

    Bellinger, Amy

    2006-01-01

    You've put off figuring out what Outline Processor Markup Language(OPML) is all about and what it can do, right? We'll bring you into the picture quickly with 14 wide-ranging uses forthe OPML format including: Reading lists and RSS subscription listsBloggingA wholly new sort of intranetProcess documentationInstant outlining and collaborationDistributed directories Included in this Short Cut are step-by-step how-to examples with illustrations to get you started using and remixing OPML right now. Let's get going.

  9. On Variational Data Assimilation in Continuous Time

    CERN Document Server

    Bröcker, Jochen

    2010-01-01

    Variational data assimilation in continuous time is revisited. The central techniques applied in this paper are in part adopted from the theory of optimal nonlinear control. Alternatively, the investigated approach can be considered as a continuous time generalisation of what is known as weakly constrained four dimensional variational assimilation (WC--4DVAR) in the geosciences. The technique allows to assimilate trajectories in the case of partial observations and in the presence of model error. Several mathematical aspects of the approach are studied. Computationally, it amounts to solving a two point boundary value problem. For imperfect models, the trade off between small dynamical error (i.e. the trajectory obeys the model dynamics) and small observational error (i.e. the trajectory closely follows the observations) is investigated. For (nearly) perfect models, this trade off turns out to be (nearly) trivial in some sense, yet allowing for some dynamical error is shown to have positive effects even in th...

  10. Dark Matter Assimilation into the Baryon Asymmetry

    CERN Document Server

    D'Eramo, Francesco; Thaler, Jesse

    2011-01-01

    Pure singlets are typically disfavored as dark matter candidates, since they generically have a thermal relic abundance larger than the observed value. In this paper, we propose a new dark matter mechanism called "assimilation", which takes advantage of the baryon asymmetry of the universe to generate the correct relic abundance of singlet dark matter. Through assimilation, dark matter itself is efficiently destroyed, but dark matter number is stored in new quasi-stable heavy states which carry the baryon asymmetry. The subsequent annihilation and late-time decay of these heavy states yields (symmetric) dark matter as well as (asymmetric) standard model baryons. We study in detail the case of pure bino dark matter by augmenting the minimal supersymmetric standard model with vector-like chiral multiplets. In the parameter range where this mechanism is effective, the LHC can discover long-lived charged particles which were responsible for assimilating dark matter.

  11. Implicit assimilation for marine ecological models

    Science.gov (United States)

    Weir, B.; Miller, R.; Spitz, Y. H.

    2012-12-01

    We use a new data assimilation method to estimate the parameters of a marine ecological model. At a given point in the ocean, the estimated values of the parameters determine the behaviors of the modeled planktonic groups, and thus indicate which species are dominant. To begin, we assimilate in situ observations, e.g., the Bermuda Atlantic Time-series Study, the Hawaii Ocean Time-series, and Ocean Weather Station Papa. From there, we estimate the parameters at surrounding points in space based on satellite observations of ocean color. Given the variation of the estimated parameters, we divide the ocean into regions meant to represent distinct ecosystems. An important feature of the data assimilation approach is that it refines the confidence limits of the optimal Gaussian approximation to the distribution of the parameters. This enables us to determine the ecological divisions with greater accuracy.

  12. Data assimilation for air quality models

    DEFF Research Database (Denmark)

    Silver, Jeremy David

    2014-01-01

    -transport models (CTMs). Each of these methods has their limitations: direct measurements provide only data at point locations and may not be representative of a wider area, remotely-sensed data from polar-orbiting satellites cannot investigate diurnal variation, and CTM simulations are often associated...... with higher uncertainties. It is possible, however, to combine information from measurements and models to more accurately estimate the state of the atmosphere using a statistically consistent framework known as “data assimilation”. In this study, three data assimilation schemes are implemented and evaluated....... The data assimilation schemes are coupled to the Danish Eulerian Hemispheric Model (DEHM), a large-scale three-dimensional off-line CTM, and the data ingested were retrievals of atmospheric composition from polar-orbiting satellites. The three assimilation techniques applied were: a three...

  13. Correction of deposition predictions with data assimilation

    International Nuclear Information System (INIS)

    Model predictions for rapid assessment and prognosis of possible radiological consequences after an accidental release of radionuclides play an important role in nuclear emergency management. Radiological measurements (e. g., dose rate measurements) can be used to improve such model predictions. This paper describes a method for combining model predictions and measurements (data assimilation) in the deposition model of the European radiological decision support system RODOS. The data assimilation approach is based on the Ensemble Kalman Filter, a Monte Carlo variant of the Kalman filter. (orig.)

  14. Data assimilation approaches in the EURANOS project

    DEFF Research Database (Denmark)

    Kaiser, J.C.; Gering, F.; Astrup, Poul;

    2010-01-01

    Within the EURANOS project data assimilation (DA) approaches have been successfully applied in two areas to improve the predictive power of simulation models used in the RODOS and ARGOS decision support systems. For the areas of atmospheric dispersion modelling and of modelling the fate of radio......-nuclides in urban areas the results of demonstration exercises are presented here. With the data assimilation module of the RIMPUFF dispersion code, predictions of the gamma dose rate are corrected with simulated readings of fixed detector stations. Using the DA capabilities of the IAMM package for mapping...

  15. You can't always get what you want: size assortative mating by mutual mate choice as a resolution of sexual conflict

    Directory of Open Access Journals (Sweden)

    Thünken Timo

    2009-06-01

    Full Text Available Abstract Background Assortative mating patterns for mate quality traits like body size are often observed in nature. However, the underlying mechanisms that cause assortative mating patterns are less well known. Sexual selection is one important explanation for assortment, suggesting that i one (usually the female or both sexes could show preferences for mates of similar size or ii mutual mate choice could resolve sexual conflict over quality traits into assortment. We tested these hypotheses experimentally in the socially monogamous cichlid fish Pelvicachromis taeniatus, in which mate choice is mutual. Results In mate choice experiments, both sexes preferred large mates irrespective of own body size suggesting mating preferences are not size-assortative. Especially males were highly selective for large females, probably because female body size signals direct fitness benefits. However, when potential mates were able to interact and assess each other mutually they showed size-assortative mating patterns, i.e. the likelihood to mate was higher in pairs with low size differences between mates. Conclusion Due to variation in body size, general preferences for large mating partners result in a sexual conflict: small, lower quality individuals who prefer themselves large partners are unacceptable for larger individuals. Relative size mismatches between mates translate into a lower likelihood to mate, suggesting that the threshold to accept mates depends on own body size. These results suggest that the underlying mechanism of assortment in P. taeniatus is mutual mate choice resolving the sexual conflict over mates, rather than preference for mates of similar size.

  16. A new sequential data assimilation method

    Institute of Scientific and Technical Information of China (English)

    HAN YueQi; ZHANG YaoCun; WANG YunFeng; YE Song; FANG HanXian

    2009-01-01

    A new sequential data assimilation method named "Monte Carlo H∞ filter" is Introduced based on H∞ filter technique and Monte Carlo method in this paper. This method applies to nonlinear systems in condition of lacking the statistical properties of observational errors. In order to compare the assimilation capability of Monte Carlo H= filter with that of the ensemble Kalman filter (EnKF) in solving practical problems caused by temporal correlation or spatial correlation of observational errors, two numerical experiments are performed by using Lorenz (1963) system and shallow-water equations respectively. The result is that the assimilation capability of the new method is better than that of EnKF method. It is also shown that Monte Carlo H∞ filter assimilation method is effective and suitable to nonlinear systems in that it does not depend on the statistical properties of observational errors and has better robustnesa than EnKF method when the statistical properties of observational errors are varying. In addition, for the new method, the smallest level factor founded by search method is flow-dependent.

  17. Economic and Cultural Assimilation and Integration of Immigration in Europe

    OpenAIRE

    Mariya Aleksynska; Yann Algan

    2010-01-01

    This paper documents assimilation of immigrants in 16 European countries along cultural, civic, and economic dimensions, distinguishing by immigrants’ generation, duration of stay, and origin. It suggests that assimilation may have multiple facets, and take place at different speed depending on the outcome in question. While assimilation along some economic outcomes may be correlated with assimilation along some cultural outcomes, such correlations are not systematic, and imply that progress ...

  18. Assimilation violation and spoken-language processing: A supplementary report

    OpenAIRE

    Weber, A

    2002-01-01

    Previous studies have shown that spoken-language processing is inhibited by violation of obligatory regressive assimilation. Weber (2001) replicated this inhibitory effect in a phoneme-monitoring study examining regressive place assimilation of nasals, but found facilitation for violation of progressive assimilation. German listeners detected the velar fricative [x] more quickly when fricative assimilation was violated (e.g., *[bIxt] or *[blInx@n]) than when no violation occurred (e.g., [baxt...

  19. ASSIMILATION SYSTEM AT DHMZ: DEVELOPMENT AND FIRST VERIFICATION RESULTS

    OpenAIRE

    Stanešić, Antonio

    2011-01-01

    Abstract: In this paper, a description of the setup for a local assimilation system for a limited area model, ALADIN (Aire Limiteé Adaptation Dynamique dévelopement InterNational), is given with a comprehensive description of the assimilation techniques used. The assimilation system at DHMZ (Meteorological and Hydrological Service of Croatia) consisted of two parts: the surface assimilation, which was used to change the state of a model land surface variables, and the upper air assimilatio...

  20. A flexible Open Data Assimilation framework

    Science.gov (United States)

    van Velzen, Nils; Ridler, Marc E.; Altaf, Umer; Madsen, Henrik; Heemink, Arnold; Dijkzeul, Johan

    2015-04-01

    Accurate and reliable real-time hydrological forecasts are essential for protection against water-related hazards, operation of infrastructure, and water resources management. Recent advances in radar rainfall estimation and forecasting, numerical weather predictions, satellite and in-situ monitoring, and faster computing facilities are opening up new opportunities in real-time hydrological forecasting. More effective use of the different information sources via data assimilation will provide the basis for producing more accurate and more reliable forecasts. In this regard, development and implementation of robust and computationally efficient data assimilation algorithms that are feasible for real-time applications remains one of the key challenges. The implementation of data assimilation techniques is traditionally in a model specific form. The disadvantage of this approach is the need to have in-depth knowledge of the numerical core computations and it does not allow to freely experiment with data assimilation algorithms and measurement sources without the need of additional programming. We present a more flexible approach to setup a forecasting system. The OpenDA data assimilation framework contains many state of the art data assimilation algorithms to easily set up a forecasting system. The setup of the framework allows users to select and experiment with various algorithms. OpenDA defines an interface between model and data assimilation algorithms. This interface only needs to be implemented once for a particular model. The OpenDA model interface is already implemented for various models. Besides these models it is very easy to couple models that are already implementing the Open Model Interface (OpenMI) to OpenDA using the generic OpenMI-OpenDA coupler. Using a synthetic test case we demonstrate the capabilities of the proposed approach using OpenMI and OpenDA. We use the MIKE SHE distributed and integrated hydrological modeling system to demonstrate how

  1. Strengths and Limitations of Data Assimilation Models

    Science.gov (United States)

    Schunk, R. W.; Scherliess, L.; Sojka, J. J.; Thompson, D. C.; Zhu, L.

    2006-12-01

    As part of the Global Assimilation of Ionospheric Measurements (USU-GAIM) program, we developed two Kalman filter data assimilation models of the global ionosphere, including Gauss-Markov (GM) and Full Physics (FP) models. Our Gauss-Markov model uses a physics-based ionospheric model and a Kalman filter as a basis for assimilating the measurements. The physics-based model is the Ionosphere Forecast Model (IFM), which is a multi-ion global model that covers the E-region, F-region, and topside from 90 to 1400 km. The GM model has both regional and global capabilities and the output of the model is a 3-dimensional Ne distribution at specified times. With the GM model the ionospheric densities obtained from the IFM constitute a background ionospheric density field on which perturbations are superimposed based on the available data sources and their errors. The density perturbations and the associated errors evolve over time via a statistical Gauss-Markov process. Our full physics data assimilation model is more sophisticated than the Gauss-Markov model. This model is based on a physics-based ionosphere-plasmasphere-polar wind model, which includes six ion species (NO+, O2+, N2+, O+, H+, and He+) and covers the low-mid latitudes from 90 to 20,000 km. In addition to the global Ne distribution, the full physics model also provides global distributions of the self-consistent drivers (neutral winds and composition, electric fields, and particle precipitation). Both models can assimilate in situ electron densities from 4 DMSP satellites, bottomside Ne profiles from 30 ionosondes, slant TECs from up to 1000 ground GPS/TEC receivers, occultation data and line-of-sight UV emissions. The USU-GAIM models are now being widely used, but as with all physics-based data assimilation models, care must be exercised because these models have both strengths and limitations. Some of the important issues relate to the quality, amount and distribution of the data, the ability to obtain

  2. Assortment of the plants in the Medieval diet in Czech countries (based on archaeobotanical finds).

    Science.gov (United States)

    Culíková, V

    2000-01-01

    The finds of remains of useful plants in archaeological objects were drawing attention already in the last century. However, it was not until after the World War II, in relation with renovation of historical cores of the towns, when a separate branch of the botany--archaeobotany constituted. In the Czech Republic it was E. Opravil who was the first to become engaged in a systematic archaeobotanical research at the beginning of the 60's. All the vegetal remains--fruits and seeds on the first place as well as pollen grains from prehistoric times to the post-medieval period, are the subjects of archaeobotany. The medieval waste pits are the richest sources of the vegetal remains. They contain a lot of diasporas of cultural as well as wild plants. The remains of useful plants are an authentic document of the vegetal component of diet. Even though some vegetal species, such as for example garlic, onion or stalk-plants, about whose cultivation we are informed from literature, occur only seldom, there appeared also the species not mentioned in literature. All the basic cereals have been known in our country already since the early Middle Ages. Wheat (Triticum aestivum) and rye (Secale cereale), as well as millet (Panicum miliaceum) that, along with buckwheat (Fagopyrum esculentum), were replaced by potatoes in the modern times were the most important. Also leguminous plants were of great importance in the diet even though their charred seeds seldom preserved. Remains of oil plants such as hemp (Cannabis sativa), flax (Linum usitatissimum) and poppy (Papaver somniferum) preserved well. It was successfully proved that cucumber (Cucumis sativus), among other numerous kinds of vegetables, was introduced by the Slavs already in the 8th century in Moravia and in the 9th century in Bohemia. The assortment of fruit was rich--especially the assortment of cultivated fruit. Among the imported kinds of fruit the first place occupied figs (Ficus carica), from the numerous finds it can

  3. Assortment of the plants in the Medieval diet in Czech countries (based on archaeobotanical finds).

    Science.gov (United States)

    Culíková, V

    2000-01-01

    The finds of remains of useful plants in archaeological objects were drawing attention already in the last century. However, it was not until after the World War II, in relation with renovation of historical cores of the towns, when a separate branch of the botany--archaeobotany constituted. In the Czech Republic it was E. Opravil who was the first to become engaged in a systematic archaeobotanical research at the beginning of the 60's. All the vegetal remains--fruits and seeds on the first place as well as pollen grains from prehistoric times to the post-medieval period, are the subjects of archaeobotany. The medieval waste pits are the richest sources of the vegetal remains. They contain a lot of diasporas of cultural as well as wild plants. The remains of useful plants are an authentic document of the vegetal component of diet. Even though some vegetal species, such as for example garlic, onion or stalk-plants, about whose cultivation we are informed from literature, occur only seldom, there appeared also the species not mentioned in literature. All the basic cereals have been known in our country already since the early Middle Ages. Wheat (Triticum aestivum) and rye (Secale cereale), as well as millet (Panicum miliaceum) that, along with buckwheat (Fagopyrum esculentum), were replaced by potatoes in the modern times were the most important. Also leguminous plants were of great importance in the diet even though their charred seeds seldom preserved. Remains of oil plants such as hemp (Cannabis sativa), flax (Linum usitatissimum) and poppy (Papaver somniferum) preserved well. It was successfully proved that cucumber (Cucumis sativus), among other numerous kinds of vegetables, was introduced by the Slavs already in the 8th century in Moravia and in the 9th century in Bohemia. The assortment of fruit was rich--especially the assortment of cultivated fruit. Among the imported kinds of fruit the first place occupied figs (Ficus carica), from the numerous finds it can

  4. Assimilative and non-assimilative color spreading in the watercolor configuration

    OpenAIRE

    Eiji eKimura; Mikako eKuroki

    2014-01-01

    A colored line flanking a darker contour will appear to spread its color onto an area enclosed by the line (watercolor effect). The watercolor effect has been characterized as an assimilative effect, but non-assimilative color spreading has also been demonstrated in the same spatial configuration; e.g., when a black inner contour (IC) is paired with a blue outer contour (OC), yellow color spreading can be observed. To elucidate visual mechanisms underlying these different color spreading effe...

  5. The Parallel Data Assimilation Framework PDAF - a flexible software framework for ensemble data assimilation

    OpenAIRE

    Nerger, Lars; Hiller, Wolfgang; Schröter, Jens

    2012-01-01

    Ensemble filter algorithms can be implemented in a generic way such that they can be applied with various models with only a minimum amount of recoding. This is possible due to the fact that ensemble filters can operate on abstract state vectors and require only limited information about the numerical model and the observational data used for a data assimilation application. To build an assimilation system, the analysis step of a filter algorithm needs to be connected to t...

  6. Direct assimilation of satellite radiance data in GRAPES variational assimilation system

    Institute of Scientific and Technical Information of China (English)

    ZHU GuoFu; XUE JiShan; ZHANG Hua; LIU ZhiQuan; ZHUANG ShiYu; HUANG LiPing; DONG PeiMing

    2008-01-01

    Variational method is capable of dealing with observations that have a complicated nonlinear relation with model variables representative of the atmospheric state, and so make it possible to directly as-similate such measured variables as satellite radiance, which have a nonlinear relation with the model variables. Assimilation of any type of observations requires a corresponding observation operator, which establishes a specific mapping from the space of the model state to the space of observation. This paper presents in detail how the direct assimilation of real satellite radiance data is implemented in the GRAPES-3DVar analysis system. It focuses on all the components of the observation operator for direct assimilation of real satellite radiance data, including a spatial interpolation operator that trans-forms variables from model grid points to observation locations, a physical transformation from model variables to observed elements with different choices of model variables, and a data quality control. Assimilation experiments, using satellite radiances such as NOAA17 AMSU-A and AMSU-B (Advanced Microwave Sounding Unit), are carried out with two different schemes. The results from these experi-ments can be physically understood and clearly reflect a rational effect of direct assimilation of satellite radiance data in GRAPES-3DVar analysis system.

  7. A computer model allowing maintenance of large amounts of genetic variability in Mendelian populations. II. The balance of forces between linkage and random assortment.

    Science.gov (United States)

    Wills, C; Miller, C

    1976-02-01

    It is shown, through theory and computer simulations of outbreeding Mendelian populations, that there may be conditions under which a balance is struck between two facotrs. The first is the advantage of random assortment, which will, when multilocus selection is for intermediate equilibrium values, lead to higher average heterozygosity than when linkage is introduced. There is some indication that random assortment is also advantageous when selection is toward a uniform distribution of equilibrium values. The second factor is the advantage of linkage between loci having positive epistatic interactions. When multilocus selection is for a bimodal distribution of equilibrium values an early advantage of random assortment is replaced by a later disadvantage. Linkage disequilibrium, which in finite populations is increased only by random or selective sampling, may hinder the movement of alleles to their selective equilibria, thus leading to the advantage of random assortment.-Some consequences of this approach to the structure of natural populations are discussed.

  8. Size-assortative mating and sexual size dimorphism are predictable from simple mechanics of mate-grasping behavior

    Directory of Open Access Journals (Sweden)

    Jablonski Piotr G

    2010-11-01

    Full Text Available Abstract Background A major challenge in evolutionary biology is to understand the typically complex interactions between diverse counter-balancing factors of Darwinian selection for size assortative mating and sexual size dimorphism. It appears that rarely a simple mechanism could provide a major explanation of these phenomena. Mechanics of behaviors can predict animal morphology, such like adaptations to locomotion in animals from various of taxa, but its potential to predict size-assortative mating and its evolutionary consequences has been less explored. Mate-grasping by males, using specialized adaptive morphologies of their forelegs, midlegs or even antennae wrapped around female body at specific locations, is a general mating strategy of many animals, but the contribution of the mechanics of this wide-spread behavior to the evolution of mating behavior and sexual size dimorphism has been largely ignored. Results Here, we explore the consequences of a simple, and previously ignored, fact that in a grasping posture the position of the male's grasping appendages relative to the female's body is often a function of body size difference between the sexes. Using an approach taken from robot mechanics we model coercive grasping of females by water strider Gerris gracilicornis males during mating initiation struggles. We determine that the male optimal size (relative to the female size, which gives the males the highest grasping force, properly predicts the experimentally measured highest mating success. Through field sampling and simulation modeling of a natural population we determine that the simple mechanical model, which ignores most of the other hypothetical counter-balancing selection pressures on body size, is sufficient to account for size-assortative mating pattern as well as species-specific sexual dimorphism in body size of G. gracilicornis. Conclusion The results indicate how a simple and previously overlooked physical mechanism

  9. Assortative mating and differential fertility by phenotype and genotype across the 20th century.

    Science.gov (United States)

    Conley, Dalton; Laidley, Thomas; Belsky, Daniel W; Fletcher, Jason M; Boardman, Jason D; Domingue, Benjamin W

    2016-06-14

    This study asks two related questions about the shifting landscape of marriage and reproduction in US society over the course of the last century with respect to a range of health and behavioral phenotypes and their associated genetic architecture: (i) Has assortment on measured genetic factors influencing reproductive and social fitness traits changed over the course of the 20th century? (ii) Has the genetic covariance between fitness (as measured by total fertility) and other traits changed over time? The answers to these questions inform our understanding of how the genetic landscape of American society has changed over the past century and have implications for population trends. We show that husbands and wives carry similar loadings for genetic factors related to education and height. However, the magnitude of this similarity is modest and has been fairly consistent over the course of the 20th century. This consistency is particularly notable in the case of education, for which phenotypic similarity among spouses has increased in recent years. Likewise, changing patterns of the number of children ever born by phenotype are not matched by shifts in genotype-fertility relationships over time. Taken together, these trends provide no evidence that social sorting is becoming increasingly genetic in nature or that dysgenic dynamics have accelerated. PMID:27247411

  10. Male mate preference and size-assortative mating in convict cichlids: A role for female aggression?

    Science.gov (United States)

    Bloch, A N; Estela, V J; Leese, J M; Itzkowitz, M

    2016-09-01

    Many monogamous species demonstrate size-assortative mating patterns within natural populations. To better understand the role of intersexual selection in this process, we examined the effect of male preference for female body size in the convict cichlid (Amatitlania siquia). We provided males with a choice between females that differed in size, relative to each other and in relation to the focal male. Based on previous work, we expected males to prefer the largest available female mates across all treatments. Surprisingly, males spent more time near the smaller of two available females, but only when the other female was larger than the male. Additionally, males spent little time with either of two potential female mates when both females were larger than the male. We hypothesized that while males might prefer the largest of available females, female behavior might limit males from acting on this preference. To test this, males were force paired with a smaller or larger female. Pair formation only occurred when the female was smaller than the male, and females that were larger than their male counterparts showed significantly more aggression when compared to smaller females. Together, these data suggest that in the absence of intrasexual competition, male mate preference for large females in convict cichlids might be limited by female aggression. PMID:27444247

  11. Assortative mating among animals of captive and wild origin following experimental conservation releases.

    Science.gov (United States)

    Slade, Brendan; Parrott, Marissa L; Paproth, Aleisha; Magrath, Michael J L; Gillespie, Graeme R; Jessop, Tim S

    2014-11-01

    Captive breeding is a high profile management tool used for conserving threatened species. However, the inevitable consequence of generations in captivity is broad scale and often-rapid phenotypic divergence between captive and wild individuals, through environmental differences and genetic processes. Although poorly understood, mate choice preference is one of the changes that may occur in captivity that could have important implications for the reintroduction success of captive-bred animals. We bred wild-caught house mice for three generations to examine mating patterns and reproductive outcomes when these animals were simultaneously released into multiple outdoor enclosures with wild conspecifics. At release, there were significant differences in phenotypic (e.g. body mass) and genetic measures (e.g. Gst and F) between captive-bred and wild adult mice. Furthermore, 83% of offspring produced post-release were of same source parentage, inferring pronounced assortative mating. Our findings suggest that captive breeding may affect mating preferences, with potentially adverse implications for the success of threatened species reintroduction programmes.

  12. Intelligent, net or wireless enabled fluorosensors for high throughput monitoring of assorted crops

    International Nuclear Information System (INIS)

    Phenotypic characterization of assorted crops of different genotypes requires large data sets of diverse types for statistical reliability. Temporal monitoring of plant fluorescence is able to capture the dynamics of the photosynthesis process that is summarized in a number of parameters for which the genotypic heritability can be calculated. In this paper, an intelligent sensor system is presented that is capable of high-throughput production of baseline-corrected temporal fluorescence curves with many feature points. These are obtained by integrating several (direct and modulated) measurement methods applied at different wavelengths. Simultaneously, temporal change of the sample's emission and the ambient reference temperatures are recorded. Multiple sensors can be deployed easily in large span greenhouse environments with centralized data collection over wired or wireless infrastructure. The unique features of the sensors are a compact, embedded signal guiding fibre optic system, instrument-standard variable tubular detector and source modules, net or wireless enabling for remote control and fast, quasi real-time data collection. Along with the instrumentation, some representative phenotyping data are also presented that were taken on a subset of pepper recombinant inbred line population. It is also demonstrated that transient fluorescence feature points yield high heritability, offering a high confidence level for distinguishing the pepper genotypes. (paper)

  13. Collaboration in sensor network research: an in-depth longitudinal analysis of assortative mixing patterns.

    Science.gov (United States)

    Pepe, Alberto; Rodriguez, Marko A

    2010-09-01

    Many investigations of scientific collaboration are based on statistical analyses of large networks constructed from bibliographic repositories. These investigations often rely on a wealth of bibliographic data, but very little or no other information about the individuals in the network, and thus, fail to illustrate the broader social and academic landscape in which collaboration takes place. In this article, we perform an in-depth longitudinal analysis of a relatively small network of scientific collaboration (N = 291) constructed from the bibliographic record of a research centerin the development and application of wireless and sensor network technologies. We perform a preliminary analysis of selected structural properties of the network, computing its range, configuration and topology. We then support our preliminary statistical analysis with an in-depth temporal investigation of the assortative mixing of selected node characteristics, unveiling the researchers' propensity to collaborate preferentially with others with a similar academic profile. Our qualitative analysis of mixing patterns offers clues as to the nature of the scientific community being modeled in relation to its organizational, disciplinary, institutional, and international arrangements of collaboration.

  14. ABC & XYZ – ANALYSIS OF ASSORTMENT OF ENTERPRISES OF BAKERY INDUSTRIES OF CONSUMER COOPERATIVES

    Directory of Open Access Journals (Sweden)

    Baranovskaya T. P.

    2015-12-01

    Full Text Available To develop detailed and effective business model of bakery enterprises of consumer cooperation it is necessary to have knowledge on strategic goods displayed on a busy segment of the market, not only in volumetric terms, but in the parameters that characterize the stability of sales or consumption. The particular relevance of this study reveals in modern conditions of functioning. The outcome of the baking enterprises of consumer cooperatives is more than 760 tons per day, distributed between 41 baking enterprise producing more than 300 kinds of products. Of course, the information on quantitative and qualitative characteristics of the strategic positions of the range will be a key in making managerial decisions about the production of the program, resourcing, turnover, etc. To solve the problem we have chosen the method of ABC - and XYZ-analysis of assortment of production, based on the criteria of ease of use and breadth of the resulting information. As a result of the application of the methods of ABC and XYZ-analysis and combining the obtained results, we present a classification of the range of the baking enterprises of consumer cooperation product based on the criteria of the contribution of commodity positions in revenue and stability of sales

  15. Characterization of assortative mating in medaka: Mate discrimination cues and factors that bias sexual preference.

    Science.gov (United States)

    Utagawa, Umi; Higashi, Shoichi; Kamei, Yasuhiro; Fukamachi, Shoji

    2016-08-01

    Somatolactin alpha (SLα) is a peptide hormone that regulates skin color, and SLα-deficient and SLα-excess strains have been established in medaka (Oryzias latipes). Their skin colors differ conspicuously and males prefer to mate with females from the same strain. Pre-mating sexual isolation in this model vertebrate provides an ideal platform for investigating the molecular mechanisms of mate choice. Thus, we studied the sensory cues utilized by these fish to discriminate the same and different strains. When males were given a choice under monochromatic light, where the skin colors differed only in terms of brightness but not in hue, mating occurred but it was not assortative. This suggests that: (1) a visual cue is essential for mate discrimination rather than odor or acoustic cues; (2) the visual cue is color and not shape, size, or motion; and (3) the color cue needs to be perceived as the relative balance of brightness at multiple wavelengths rather than the brightness at a specific wavelength. In addition, we introduced another skin-color mutation into the SLα-excess strain and found that this new strain and the original SLα-excess strain, which also overexpressed SLα but exhibited distinct skin colors, preferred different colors. This demonstrates that SLα is not a primary determinant of sexual preference. The symmetrically biased sexual preferences of the SLα-deficient and SLα-excess strains may be acquired postnatally depending on their individual skin color or that of tank mates. PMID:27260680

  16. PHYLLOXERA-RESISTANT HYBRID FORM OF GRAPES OF TECHNICAL SORTS FOR IMPROVING THE ASSORTMENT

    Directory of Open Access Journals (Sweden)

    Larkina M. D.

    2015-10-01

    Full Text Available Many old varieties of grapes do not meet modern requirements, so there is a need for improved assortment of new high-quality varieties. The translation of the vineyards of the black sea coast of the Krasnodar region on inoculated culture is not fully decided the fate of the viticulture of the area. Weak resistance of American rootstocks to increased content of calcium and salts in the soil, caused the weakening of the bushes, reducing the vigor of the shoots, their maturation and yield of grape plantations in some areas of the district while reducing their quality indicators. In this regard, the development of new high-yielding varieties suitable for own-rooted viticulture remains the most urgent task for breeders. The article shows the potential of many years of breeding work and study of grapes of technical varieties in Anapa Zone Station, tolerant to phylloxera and resistant to fungal diseases and frost, with high quality products and gives a brief description of some prominent grape varieties

  17. 分类觅食人工鱼群算法%Assorted foraging artificial fish swarm algorithm

    Institute of Scientific and Technical Information of China (English)

    李辉

    2016-01-01

    针对人工鱼群算法搜索速度和搜索精度不高,且对高维问题寻优能力较差等缺点,提出了一种改进的人工鱼群算法——分类觅食人工鱼群算法(Assorted Foraging Artificial Fish Swarm Algorithm-AFAFSA).该算法对执行觅食行为的个体分类进行更新,既保持种群的多样性又通过觅食行为加快算法的搜索速度,同时加入禁忌的思想帮助算法跳出局部最优,提高算法的性能.通过一系列的测试试验,发现改进算法在收敛速度和精度方面都有了明显的提高,对于高维问题有也具有较好的寻优能力.

  18. Male size does not correlate with fertilization success in two bufonid toads that show size-assortative mating

    Directory of Open Access Journals (Sweden)

    Xiao-Li FAN, Zhi-Hua LIN, Xiang JI

    2013-12-01

    Full Text Available We examined sexual size dimorphism (SSD, mating pattern, fertilization efficiency and female reproductive traits in two bufonid toads (Bufo gargarizans and Duttaphrynus melanostictus to test the idea that importance of male body size for egg fertilization success depends on the mating pattern. Female-biased SSD was evident only in D. melanostictus. Female B. gargarizans laid fewer larger eggs nearly three months earlier than did female D. melanostictus. Fertilization efficiencies on average were higher in B. gargarizans (95% than in D. melanostictus (91%. Though differing in the degree of SSD, body size, breeding season, clutch size, egg size and fertilization efficiency, the two toads were similar in four aspects: (1 both showed size-assortative mating; (2 females did not tradeoff egg size against egg number; (3 male size, clutch size and clutch dry mass were greater in male-larger than in female-larger pairs after accounting for female snout-vent length (SVL; and (4 the ratio of male to female SVL did not affect fertilization efficiency. Our data show that: (1 a female preference for large males is likely not important in terms of egg fertilization success; (2 a male preference for large females is likely important because larger females are more fecund; and (3 size-assortative mating arises from a male preference for large females. Our study demonstrates that male size is not always important for egg fertilization success in anurans that show size-assortative mating [Current Zoology 59 (6: 740–746, 2013].

  19. Characteristic strategy of assimilation of various saccharides by Clostridium cellulovorans.

    Science.gov (United States)

    Inamori, Takako; Aburaya, Shunsuke; Morisaka, Hironobu; Kuroda, Kouichi; Ueda, Mitsuyoshi

    2016-12-01

    Clostridium cellulovorans can effectively assimilate not only cellulose but also hemicellulose by producing cellulosomal and non-cellulosomal enzymes. However, little is known about how C. cellulovorans assimilates various saccharides in media containing polysaccharides and oligosaccharides. In this research, we investigated the property of saccharide incorporation and assimilation by C. cellulovorans. Faster growth in media containing xylan and cellulose was achieved by switching polysaccharides, in which xylan was first assimilated, followed by cellulose. Furthermore, the presence of polysaccharides that can be easily degraded might increase the assimilation rate of lignocellulose by promoting growth. These properties of C. cellulovorans could be suitable for the effective utilization of lignocellulosic biomass.

  20. Strong assortative mating by diet, color, size, and morphology but limited progress toward sympatric speciation in a classic example: Cameroon crater lake cichlids.

    Science.gov (United States)

    Martin, Christopher H

    2013-07-01

    Models predict that sympatric speciation depends on restrictive parameter ranges, such as sufficiently strong disruptive selection and assortative mating, but compelling examples in nature have rarely been used to test these predictions. I measured the strength of assortative mating within a species complex of Tilapia in Lake Ejagham, Cameroon, a celebrated example of incipient sympatric adaptive radiation. This species complex is in the earliest stages of speciation: morphological and ecological divergence are incomplete, species differ primarily in breeding coloration, and introgression is common. I captured 27 mated pairs in situ and measured the diet, color, size, and morphology of each individual. I found strong assortative mating by color, size, head depth, and dietary source of benthic or pelagic prey along two independent dimensions of assortment. Thus, Ejagham Tilapia showed strong assortative mating most conducive to sympatric speciation. Nonetheless, in contrast to a morphologically bimodal Sarotherodon cichlid species pair in the lake, Ejagham Tilapia show more limited progress toward speciation, likely due to insufficient strength of disruptive selection on morphology estimated in a previous study (γ = 0.16). This supports the predicted dependence of sympatric speciation on strong assortment and strong disruptive selection by examining a potentially stalled example in nature. PMID:23815664

  1. Effect of S-07 on 14CO2 assimilation and distribution of assimilates during ripening stage of wheat

    International Nuclear Information System (INIS)

    The effect of S-07 (S-3307, uniconazole) on 14CO2 assimilation and distribution of assimilates during ripening stage of wheat was studied. The experimental results showed that the amount of 14Co2 assimilates in leaves of the wheat plant sprayed with 10∼40 ppm S-07 at heading stage was higher than that of the control. The distribution of 14CO2 assimilates in ear and root of wheat plant increased. It is also found that S-07 treatment made more assimilates transferring from primary stem to tillers

  2. The "textbook Gibson": The assimilation of dissidence.

    Science.gov (United States)

    Costall, Alan; Morris, Paul

    2015-02-01

    We examine how the textbooks have dealt with one of psychology's most eminent dissidents, James Gibson (1904-1979). Our review of more than a hundred textbooks, dating from the 1950s to the present, reveals fundamental and systematic misrepresentations of Gibson. Although Gibson continues to figure in most of the textbooks, his work is routinely assimilated to theoretical positions he emphatically rejected: cue theory, stimulus-response psychology, and nativism. As Gibson's one-time colleague, Ulric Neisser, pointed out, psychologists are especially prone to trying to understand new proposals "by mapping it on to some existing scheme," and warned that when "an idea is really new, that strategy fails" (Neisser, 1990, p. 749). The "Textbook Gibson" is an example of such a failure, and perhaps also of the more general importance of assimilation-"shadow history"-within the actual history of psychology. PMID:25664882

  3. Complexity Computational Environment: Data Assimilation SERVOGrid

    Science.gov (United States)

    Donnellan, Andrea; Parker, Jay; Fox, Geoffrey; Pierce, Marlon; Rundle, John; McLeod, Dennis

    2004-01-01

    We are using Web (Grid) service technology to demonstrate the assimilation of multiple distributed data sources (a typical data grid problem) into a major parallel high-performance computing earthquake forecasting code. Such a linkage of Geoinformatics with Geocomplexity demonstrates the value of the Solid Earth Research Virtual Observatory (SERVO) Grid concept, and advance Grid technology by building the first real-time large-scale data assimilation grid Here we develop the next steps for both the SERVO concept and the identified need for a Solid Earth problem-solving environment. We use a challenging motivating problem of importance to NASA namely integrating NASA space geodetic observations with numerical simulations of a changing earth.

  4. Probabilistic forecasting and Bayesian data assimilation

    CERN Document Server

    Reich, Sebastian

    2015-01-01

    In this book the authors describe the principles and methods behind probabilistic forecasting and Bayesian data assimilation. Instead of focusing on particular application areas, the authors adopt a general dynamical systems approach, with a profusion of low-dimensional, discrete-time numerical examples designed to build intuition about the subject. Part I explains the mathematical framework of ensemble-based probabilistic forecasting and uncertainty quantification. Part II is devoted to Bayesian filtering algorithms, from classical data assimilation algorithms such as the Kalman filter, variational techniques, and sequential Monte Carlo methods, through to more recent developments such as the ensemble Kalman filter and ensemble transform filters. The McKean approach to sequential filtering in combination with coupling of measures serves as a unifying mathematical framework throughout Part II. Assuming only some basic familiarity with probability, this book is an ideal introduction for graduate students in ap...

  5. Data assimilation in integrated hydrological modelling

    DEFF Research Database (Denmark)

    Rasmussen, Jørn

    Integrated hydrological models are useful tools for water resource management and research, and advances in computational power and the advent of new observation types has resulted in the models generally becoming more complex and distributed. However, the models are often characterized by a high...... using both synthetic data and real observations. Groundwater head and stream discharge observations are assimilated in an integrated hydrological model, with the aim of updating the groundwater head, stream discharge and water level, and model parameters. When synthetically generated observations...... degree of parameterization which results in significant model uncertainty which cannot be reduced much due to observations often being scarce and often taking the form of point measurements. Data assimilation shows great promise for use in integrated hydrological models , as it allows for observations...

  6. Reduction of complexity and variational data assimilation

    OpenAIRE

    Maday, Yvon

    2015-01-01

    Reduced basis methods belong to a class of approaches of \\emph{model reduction} for the approximation of the solution of mathematical models involved in many fields of research or decision making and in data assimilation. These approaches allow to tackle, in --- close to --- real time, problems requiring, a priori, a large number of computations by formalizing two steps : one known as "offline stage” that is a preparation step and is quite costly and an ``online stage'' that is used on dema...

  7. Services innovation: assimilation, differentiation, inversion and integration

    OpenAIRE

    Gallouj, FaÏz

    2002-01-01

    This chapter aims to provide a review of the literature on innovation in services and to focus on the analytical strategies carried out in order to fill in the innovation gap in the service economy (i.e. the difference between what the traditional innovation indicators are capable of capturing, and the reality of innovation activities undertaken in a given economy). Four analytical perspectives are distinguished in this chapter, which are labeled: assimilation, differentiation, inversion and ...

  8. Ethnic Persistence, Assimilation and Risk Proclivity

    OpenAIRE

    Bonin, Holger; Constant, Amelie; Tatsiramons, Konstantinos; Zimmermann, Klaus F.

    2007-01-01

    The paper investigates the role of social norms as a determinant of individual attitudes by analyzing risk proclivity reported by immigrants and natives in a unique representative German survey. We employ factor analysis to construct measures of immigrants' ethnic persistence and assimilation. The estimated effect of these measures on risk proclivity suggests that adaptation to the attitudes of the majority population closes the immigrant-native gap in risk proclivity, while stronger commitme...

  9. Immigrants and Gender Roles: Assimilation vs. Culture

    OpenAIRE

    Francine D. Blau

    2015-01-01

    This paper examines evidence on the role of assimilation versus source country culture in influencing immigrant women's behavior in the United States – looking both over time with immigrants' residence in the United States and across immigrant generations. It focuses particularly on labor supply but, for the second generation, also examines fertility and education. We find considerable evidence that immigrant source country gender roles influence immigrant and second generation women's behavi...

  10. Reconstructing mammalian sleep dynamics with data assimilation.

    Directory of Open Access Journals (Sweden)

    Madineh Sedigh-Sarvestani

    Full Text Available Data assimilation is a valuable tool in the study of any complex system, where measurements are incomplete, uncertain, or both. It enables the user to take advantage of all available information including experimental measurements and short-term model forecasts of a system. Although data assimilation has been used to study other biological systems, the study of the sleep-wake regulatory network has yet to benefit from this toolset. We present a data assimilation framework based on the unscented Kalman filter (UKF for combining sparse measurements together with a relatively high-dimensional nonlinear computational model to estimate the state of a model of the sleep-wake regulatory system. We demonstrate with simulation studies that a few noisy variables can be used to accurately reconstruct the remaining hidden variables. We introduce a metric for ranking relative partial observability of computational models, within the UKF framework, that allows us to choose the optimal variables for measurement and also provides a methodology for optimizing framework parameters such as UKF covariance inflation. In addition, we demonstrate a parameter estimation method that allows us to track non-stationary model parameters and accommodate slow dynamics not included in the UKF filter model. Finally, we show that we can even use observed discretized sleep-state, which is not one of the model variables, to reconstruct model state and estimate unknown parameters. Sleep is implicated in many neurological disorders from epilepsy to schizophrenia, but simultaneous observation of the many brain components that regulate this behavior is difficult. We anticipate that this data assimilation framework will enable better understanding of the detailed interactions governing sleep and wake behavior and provide for better, more targeted, therapies.

  11. National Identity and Immigrants’ Assimilation in France

    OpenAIRE

    Gabin Langevin; Pascaline Vincent

    2013-01-01

    Determination and changes of immigrants' identity resulting from intercultural contacts impact their socio-economic integration. To precisely assess individuals’ identity, we propose a continuous index which aims to overcome interpretation troubles faced by usual measures of ethnic identity. Then, we investigate the determinants of immigrants' ethnic identity in France. We compare our composite and continuous index exhibiting individuals' assimilation with a usual measure of ethnic identity –...

  12. Immigrant Assimilation, Trust and Social Capital

    OpenAIRE

    Cox, James C.; Orman, Wafa Hakim

    2010-01-01

    Trust is a crucial component of social capital. We use an experimental moonlighting game with a representative sample of the U.S. population, oversampling immigrants, to study trust, positive, and negative reciprocity between first-generation immigrants and native-born Americans as a measure of immigrant assimilation. We also survey subjects in order to relate trusting and trustworthy behavior with demographic characteristics and traditional, survey-based measures of social capital. We find t...

  13. Assimilation and cohort effects for German immigrants

    OpenAIRE

    Gundel, Sebastian; Peters, Heiko

    2008-01-01

    Demographic change and the rising demand for highly qualified labor in Germany attracts notice to the analysis of immigration. In addition, the pattern of immigration changed markedly during the past decades. Therefore we use the latest data of the German Socioeconomic Panel up to the year 2006 in order to investigate the economic performance of immigrants. We perform regressions of three pooled cross sections (1986, 1996, 2006) to estimate assimilation and quality of immigrants as reflected ...

  14. Wage Assimilation of Immigrants in Spain

    OpenAIRE

    Zenón Jiménez-Ridruejo; Carlos Borondo Arribas

    2011-01-01

    In this study we quantify the effect of the years of residence in Spain on the earnings of immigrants. We take sex, origin, education and age into account. The results are clearly positive, the longer the length of residence the more earnings, confirming the hypothesis of wage assimilation of immigrants as their human capital is adapted to the Spanish labor market. The information used comes from the Social Security’s Continuous Sample of Working Lives 2007. Additionally, we merge the earning...

  15. Intermarriage and the Economic Assimilation of Immigrants

    OpenAIRE

    Xin Meng; Robert G Gregory

    2005-01-01

    This article investigates the assimilation role of intermarriage between immigrants and natives. Intermarried immigrants earn significantly higher incomes than endogamously married immigrants, even after we take account of human capital endowments and endogeneity of intermarriage. The premium does not appear to be a reward for unobservable individual characteristics. Natives who intermarry do not receive this premium, nor do immigrants who intermarry into another ethnic group. The premium is ...

  16. Precision variational approximations in statistical data assimilation

    Directory of Open Access Journals (Sweden)

    J. Ye

    2014-10-01

    Full Text Available Data assimilation transfers information from observations of a complex system to physically-based system models with state variables x(t. Typically, the observations are noisy, the model has errors, and the initial state of the model is uncertain, so the data assimilation is statistical. One can thus ask questions about expected values of functions ⟨G(X⟩ on the path X = {x(t0, ..., x(tm} of the model as it moves through an observation window where measurements are made at times {t0, ..., tm}. The probability distribution on the path P(X = exp[−A0(X] determines these expected values. Variational methods seeking extrema of the "action" A0(X, widely known as 4DVar (Talagrand and Courtier, 1987; Evensen, 2009,, are widespread for estimating ⟨G(X ⟩ in many fields of science. In a path integral formulation of statistical data assimilation, we consider variational approximations in a standard realization of the action where measurement and model errors are Gaussian. We (a discuss an annealing method for locating the path X0 giving a consistent global minimum of the action A0(X0, (b consider the explicit role of the number of measurements at each measurement time in determining A0(X0, and (c identify a parameter regime for the scale of model errors which allows X0 to give a precise estimate of ⟨G(X0⟩ with computable, small higher order corrections.

  17. SMAP Data Assimilation at the GMAO

    Science.gov (United States)

    Reichle, R.; De Lannoy, G.; Liu, Q.; Ardizzone, J.

    2016-01-01

    The NASA Soil Moisture Active Passive (SMAP) mission has been providing L-band (1.4 GHz) passive microwave brightness temperature (Tb) observations since April 2015. These observations are sensitive to surface(0-5 cm) soil moisture. Several of the key applications targeted by SMAP, however, require knowledge of deeper-layer, root zone (0-100 cm) soil moisture, which is not directly measured by SMAP. The NASA Global Modeling and Assimilation Office (GMAO) contributes to SMAP by providing Level 4 data, including the Level 4 Surface and Root Zone Soil Moisture(L4_SM) product, which is based on the assimilation of SMAP Tb observations in the ensemble-based NASA GEOS-5 land surface data assimilation system. The L4_SM product offers global data every three hours at 9 km resolution, thereby interpolating and extrapolating the coarser- scale (40 km) SMAP observations in time and in space (both horizontally and vertically). Since October 31, 2015, beta-version L4_SM data have been available to the public from the National Snow and Ice Data Center for the period March 31, 2015, to near present, with a mean latency of approx. 2.5 days.

  18. Targeting iron assimilation to develop new antibacterials

    Science.gov (United States)

    Foley, Timothy L.; Simeonov, Anton

    2012-01-01

    Introduction Since the first application of antibiotics to treat bacterial infections, the development and spread of resistance has been a persistent threat. An ever-evolving pipeline of next-generation therapeutics is required for modern medicine to remain one step ahead of pathogens. Areas covered in this review This review describes recent efforts to develop drugs that interrupt the assimilation of iron by bacteria, a process that is vital to cellular homeostasis and is not currently targeted by antibiotics used in the clinic. We cover the mechanisms through which bacteria acquire iron for their environment and detail efforts to intervene in these processes with small molecule inhibitors that target key steps in these pathways, with a special emphasis on recent advances published during the 2010–2012 period. Expert Opinion For decades, the routes used by bacteria to assimilate iron from host and environmental settings have been the subject of intense study. While numerous investigations have identified inhibitors of these pathways, many have stopped short of translating the in vitro results to in vivo proof of concept experiments. Extension of preliminary findings in this manner to validate the clinical potential of iron assimilation pathways for therapeutic development will significantly increase the impact of the field. PMID:22812521

  19. A new sequential data assimilation method

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    A new sequential data assimilation method named "Monte Carlo H ∞ filter" is introduced based on H ∞ filter technique and Monte Carlo method in this paper. This method applies to nonlinear systems in condition of lacking the statistical properties of observational errors. In order to compare the as- similation capability of Monte Carlo H ∞ filter with that of the ensemble Kalman filter (EnKF) in solving practical problems caused by temporal correlation or spatial correlation of observational errors, two numerical experiments are performed by using Lorenz (1963) system and shallow-water equations re- spectively. The result is that the assimilation capability of the new method is better than that of EnKF method. It is also shown that Monte Carlo H ∞ filter assimilation method is effective and suitable to nonlinear systems in that it does not depend on the statistical properties of observational errors and has better robustness than EnKF method when the statistical properties of observational errors are varying. In addition, for the new method, the smallest level factor founded by search method is flow-dependent.

  20. Data Assimilation and Model Evaluation Experiment Datasets.

    Science.gov (United States)

    Lai, Chung-Chieng A.; Qian, Wen; Glenn, Scott M.

    1994-05-01

    The Institute for Naval Oceanography, in cooperation with Naval Research Laboratories and universities, executed the Data Assimilation and Model Evaluation Experiment (DAMÉE) for the Gulf Stream region during fiscal years 1991-1993. Enormous effort has gone into the preparation of several high-quality and consistent datasets for model initialization and verification. This paper describes the preparation process, the temporal and spatial scopes, the contents, the structure, etc., of these datasets.The goal of DAMEE and the need of data for the four phases of experiment are briefly stated. The preparation of DAMEE datasets consisted of a series of processes: 1)collection of observational data; 2) analysis and interpretation; 3) interpolation using the Optimum Thermal Interpolation System package; 4) quality control and re-analysis; and 5) data archiving and software documentation.The data products from these processes included a time series of 3D fields of temperature and salinity, 2D fields of surface dynamic height and mixed-layer depth, analysis of the Gulf Stream and rings system, and bathythermograph profiles. To date, these are the most detailed and high-quality data for mesoscale ocean modeling, data assimilation, and forecasting research. Feedback from ocean modeling groups who tested this data was incorporated into its refinement.Suggestions for DAMEE data usages include 1) ocean modeling and data assimilation studies, 2) diagnosis and theorectical studies, and 3) comparisons with locally detailed observations.

  1. Multi-locus assortment (MLA for transgene dispersal and elimination in mosquito populations.

    Directory of Open Access Journals (Sweden)

    Jason L Rasgon

    Full Text Available BACKGROUND: Replacement of wild-type mosquito populations with genetically modified versions is being explored as a potential strategy to control vector-borne diseases. Due to lower expected relative fitness of transgenic individuals, transgenes must be driven into populations for these scenarios to be successful. Several gene drive mechanisms exist in a theoretical sense but none are currently workable in mosquitoes. Even if strategies were workable, it would be very difficult to recall released transgenes in the event of unforeseen consequences. What is needed is a way to test transgenes in the field for feasibility, efficacy and safety prior to releasing an active drive mechanism. METHODOLOGY/PRINCIPAL FINDINGS: We outline a method, termed Multi-locus assortment (MLA, to spread transgenes into vector populations by the release of genetically-modified mosquitoes carrying multiple stable transgene inserts. Simulations indicate that [1] insects do not have to carry transgenes at more than 4 loci, [2] transgenes can be maintained at high levels by sequential small releases, the frequency of which depends on the construct fitness cost, and [3] in the case of unforeseen negative non-target effects, transgenes can be eliminated from the population by halting transgenic releases and/or mass releases of wild-type insects. We also discuss potential methods to create MLA mosquito strains in the laboratory. CONCLUSIONS/SIGNIFICANCE: While not as efficient as active drive mechanisms, MLA has other advantages: [1] MLA strains can be constructed for some mosquito species with currently-available technology, [2] MLA will allow the ecological components of transgenic mosquito releases to be tested before actual gene drive mechanisms are ready to be deployed, [3] since MLA is not self-propagating, the risk of an accidental premature release into nature is minimized, and [4] in the case that active gene drive mechanisms prove impossible to develop, the MLA

  2. Molecular Assortment of Lens Species with Different Adaptations to Drought Conditions Using SSR Markers.

    Science.gov (United States)

    Singh, Dharmendra; Singh, Chandan Kumar; Tomar, Ram Sewak Singh; Taunk, Jyoti; Singh, Ranjeet; Maurya, Sadhana; Chaturvedi, Ashish Kumar; Pal, Madan; Singh, Rajendra; Dubey, Sarawan Kumar

    2016-01-01

    The success of drought tolerance breeding programs can be enhanced through molecular assortment of germplasm. This study was designed to characterize molecular diversity within and between Lens species with different adaptations to drought stress conditions using SSR markers. Drought stress was applied at seedling stage to study the effects on morpho-physiological traits under controlled condition, where tolerant cultivars and wilds showed 12.8-27.6% and 9.5-23.2% reduction in seed yield per plant respectively. When juxtaposed to field conditions, the tolerant cultivars (PDL-1 and PDL-2) and wild (ILWL-314 and ILWL-436) accessions showed 10.5-26.5% and 7.5%-15.6% reduction in seed yield per plant, respectively under rain-fed conditions. The reductions in seed yield in the two tolerant cultivars and wilds under severe drought condition were 48-49% and 30.5-45.3% respectively. A set of 258 alleles were identified among 278 genotypes using 35 SSR markers. Genetic diversity and polymorphism information contents varied between 0.321-0.854 and 0.299-0.836, with mean value of 0.682 and 0.643, respectively. All the genotypes were clustered into 11 groups based on SSR markers. Tolerant genotypes were grouped in cluster 6 while sensitive ones were mainly grouped into cluster 7. Wild accessions were separated from cultivars on the basis of both population structure and cluster analysis. Cluster analysis has further grouped the wild accessions on the basis of species and sub-species into 5 clusters. Physiological and morphological characters under drought stress were significantly (P = 0.05) different among microsatellite clusters. These findings suggest that drought adaptation is variable among wild and cultivated genotypes. Also, genotypes from contrasting clusters can be selected for hybridization which could help in evolution of better segregants for improving drought tolerance in lentil. PMID:26808306

  3. Molecular Assortment of Lens Species with Different Adaptations to Drought Conditions Using SSR Markers.

    Directory of Open Access Journals (Sweden)

    Dharmendra Singh

    Full Text Available The success of drought tolerance breeding programs can be enhanced through molecular assortment of germplasm. This study was designed to characterize molecular diversity within and between Lens species with different adaptations to drought stress conditions using SSR markers. Drought stress was applied at seedling stage to study the effects on morpho-physiological traits under controlled condition, where tolerant cultivars and wilds showed 12.8-27.6% and 9.5-23.2% reduction in seed yield per plant respectively. When juxtaposed to field conditions, the tolerant cultivars (PDL-1 and PDL-2 and wild (ILWL-314 and ILWL-436 accessions showed 10.5-26.5% and 7.5%-15.6% reduction in seed yield per plant, respectively under rain-fed conditions. The reductions in seed yield in the two tolerant cultivars and wilds under severe drought condition were 48-49% and 30.5-45.3% respectively. A set of 258 alleles were identified among 278 genotypes using 35 SSR markers. Genetic diversity and polymorphism information contents varied between 0.321-0.854 and 0.299-0.836, with mean value of 0.682 and 0.643, respectively. All the genotypes were clustered into 11 groups based on SSR markers. Tolerant genotypes were grouped in cluster 6 while sensitive ones were mainly grouped into cluster 7. Wild accessions were separated from cultivars on the basis of both population structure and cluster analysis. Cluster analysis has further grouped the wild accessions on the basis of species and sub-species into 5 clusters. Physiological and morphological characters under drought stress were significantly (P = 0.05 different among microsatellite clusters. These findings suggest that drought adaptation is variable among wild and cultivated genotypes. Also, genotypes from contrasting clusters can be selected for hybridization which could help in evolution of better segregants for improving drought tolerance in lentil.

  4. Testing the niche apportionment hypothesis with parasite communities: is random assortment always the rule?

    Science.gov (United States)

    Muñoz, G; Mouillot, D; Poulin, R

    2006-05-01

    Niche apportionment models have only been applied once to parasite communities. Only the random assortment model (RA), which indicates that species abundances are independent from each other and that interspecific competition is unimportant, provided a good fit to 3 out of 6 parasite communities investigated. The generality of this result needs to be validated, however. In this study we apply 5 niche apportionment models to the parasite communities of 14 fish species from the Great Barrier Reef. We determined which model fitted the data when using either numerical abundance or biomass as an estimate of parasite abundance, and whether the fit of niche apportionment models depends on how the parasite community is defined (e.g. ecto, endoparasites or all parasites considered together). The RA model provided a good fit for the whole community of parasites in 7 fish species when using biovolume (as a surrogate of biomass) as a measure of species abundance. The RA model also fitted observed data when ecto- and endoparasites were considered separately, using abundance or biovolume, but less frequently. Variation in fish sizes among species was not associated with the probability of a model fitting the data. Total numerical abundance and biovolume of parasites were not related across host species, suggesting that they capture different aspects of abundance. Biovolume is not only a better measurement to use with niche-orientated models, it should also be the preferred descriptor to analyse parasite community structure in other contexts. Most of the biological assumptions behind the RA model, i.e. randomness in apportioning niche space, lack of interspecific competition, independence of abundance among different species, and species with variable niches in changeable environments, are in accordance with some previous findings on parasite communities. Thus, parasite communities may generally be unsaturated with species, with empty niches, and interspecific interactions may

  5. Molecular Assortment of Lens Species with Different Adaptations to Drought Conditions Using SSR Markers.

    Science.gov (United States)

    Singh, Dharmendra; Singh, Chandan Kumar; Tomar, Ram Sewak Singh; Taunk, Jyoti; Singh, Ranjeet; Maurya, Sadhana; Chaturvedi, Ashish Kumar; Pal, Madan; Singh, Rajendra; Dubey, Sarawan Kumar

    2016-01-01

    The success of drought tolerance breeding programs can be enhanced through molecular assortment of germplasm. This study was designed to characterize molecular diversity within and between Lens species with different adaptations to drought stress conditions using SSR markers. Drought stress was applied at seedling stage to study the effects on morpho-physiological traits under controlled condition, where tolerant cultivars and wilds showed 12.8-27.6% and 9.5-23.2% reduction in seed yield per plant respectively. When juxtaposed to field conditions, the tolerant cultivars (PDL-1 and PDL-2) and wild (ILWL-314 and ILWL-436) accessions showed 10.5-26.5% and 7.5%-15.6% reduction in seed yield per plant, respectively under rain-fed conditions. The reductions in seed yield in the two tolerant cultivars and wilds under severe drought condition were 48-49% and 30.5-45.3% respectively. A set of 258 alleles were identified among 278 genotypes using 35 SSR markers. Genetic diversity and polymorphism information contents varied between 0.321-0.854 and 0.299-0.836, with mean value of 0.682 and 0.643, respectively. All the genotypes were clustered into 11 groups based on SSR markers. Tolerant genotypes were grouped in cluster 6 while sensitive ones were mainly grouped into cluster 7. Wild accessions were separated from cultivars on the basis of both population structure and cluster analysis. Cluster analysis has further grouped the wild accessions on the basis of species and sub-species into 5 clusters. Physiological and morphological characters under drought stress were significantly (P = 0.05) different among microsatellite clusters. These findings suggest that drought adaptation is variable among wild and cultivated genotypes. Also, genotypes from contrasting clusters can be selected for hybridization which could help in evolution of better segregants for improving drought tolerance in lentil.

  6. Educational attainment influences levels of homozygosity through migration and assortative mating.

    Directory of Open Access Journals (Sweden)

    Abdel Abdellaoui

    Full Text Available Individuals with a higher education are more likely to migrate, increasing the chance of meeting a spouse with a different ancestral background. In this context, the presence of strong educational assortment can result in greater ancestry differences within more educated spouse pairs, while less educated individuals are more likely to mate with someone with whom they share more ancestry. We examined the association between educational attainment and F roh (= the proportion of the genome consisting of runs of homozygosity [ROHs] in ~2,000 subjects of Dutch ancestry. The subjects' own educational attainment showed a nominally significant negative association with F roh (p = .045, while the contribution of parental education to offspring F roh was highly significant (father: p < 10(-5; mother: p = 9 × 10(-5, with more educated parents having offspring with fewer ROHs. This association was significantly and fully mediated by the physical distance between parental birthplaces (paternal education: pmediation = 2.4 × 10(-4; maternal education: pmediation = 2.3 × 10(-4, which itself was also significantly associated with F roh (p = 9 × 10(-5. Ancestry-informative principal components from the offspring showed a significantly decreasing association with geography as parental education increased, consistent with the significantly higher migration rates among more educated parents. Parental education also showed a high spouse correlation (Spearman's ρ = .66, p = 3 × 10(-262. We show that less educated parents are less likely to mate with the more mobile parents with a higher education, creating systematic differences in homozygosity due to ancestry differences not directly captured by ancestry-informative principal components (PCs. Understanding how behaviors influence the genomic structure of a population is highly valuable for studies on the genetic etiology of behavioral, cognitive, and social traits.

  7. The Importance of Peers: Assimilation Patterns among Second-generation Turkish Immigrants in Western Europe

    OpenAIRE

    Ali, S; Fokkema, T.

    2015-01-01

    The two dominant approaches to immigrant assimilation, segmented assimilation and "new" assimilation theories, have been successful at reporting and analyzing between-group differences in assimilation patterns. However, studies of assimilation generally do not address differences at the individual level. Current theories of assimilation cannot answer the simple question that gets to the heart of individual-level differences: how do you account for siblings in the same family assimilating in d...

  8. Ensemble-Based Assimilation of Aerosol Observations in GEOS-5

    Science.gov (United States)

    Buchard, V.; Da Silva, A.

    2016-01-01

    MERRA-2 is the latest Aerosol Reanalysis produced at NASA's Global Modeling Assimilation Office (GMAO) from 1979 to present. This reanalysis is based on a version of the GEOS-5 model radiatively coupled to GOCART aerosols and includes assimilation of bias corrected Aerosol Optical Depth (AOD) from AVHRR over ocean, MODIS sensors on both Terra and Aqua satellites, MISR over bright surfaces and AERONET data. In order to assimilate lidar profiles of aerosols, we are updating the aerosol component of our assimilation system to an Ensemble Kalman Filter (EnKF) type of scheme using ensembles generated routinely by the meteorological assimilation. Following the work performed with the first NASA's aerosol reanalysis (MERRAero), we first validate the vertical structure of MERRA-2 aerosol assimilated fields using CALIOP data over regions of particular interest during 2008.

  9. Construction and Experiment of Hierarchical Bayesian Network in Data Assimilation

    International Nuclear Information System (INIS)

    A Hierarchical Bayesian Network Algorithm (HBN) is developed for data assimilation and tested with an instance of soil moisture assimilation from hydrological model and ground observations. In this work, data assimilation separates into data level, process level and parameter level, and conditional probability models are defined for each level. The data model mainly deals with the scale differences between multiple data, while the process model is designed to take account of non-stationary process. Soil moisture from Soil Moisture Experiment in 2003 and Variable Infiltration Capacity Model is sequentially assimilated with HBN. The result shows that the assimilation with HBN provides spatial and temporal distribution information of soil moisture and the assimilation result agrees well with the ground observations

  10. Segmented assimilation, neighborhood disadvantage, and Hispanic immigrant health.

    Science.gov (United States)

    Akresh, Ilana Redstone; Do, D Phuong; Frank, Reanne

    2016-01-01

    We use a subset of Hispanics from the New Immigrant Survey, a nationally representative data set on immigrants recently granted legal permanent residency (n = 2245), to examine whether the relationship between assimilation and health is modified by neighborhood disadvantage and, in doing so, carry out an empirical test of the segmented assimilation hypothesis. Results indicate that assimilation in the least disadvantaged neighborhoods can be protective against poor health. Specifically, more assimilated men and women in the lowest disadvantage neighborhoods have a lower likelihood of self-reported poorer health and being overweight, respectively; no link was found in higher disadvantage neighborhoods. Assimilation was not found to be associated with self-reported health for women or BMI for men, regardless of neighborhood disadvantage level. Overall, we find some evidence supporting the hypothesis that the effects of assimilation on health depend on the context in which immigrants experience it. PMID:26708247

  11. Using ensemble data assimilation to forecast hydrological flumes

    OpenAIRE

    Amour, I.; Mussa, Z.; Bibov, A.; Kauranne, T.

    2013-01-01

    Data assimilation, commonly used in weather forecasting, means combining a mathematical forecast of a target dynamical system with simultaneous measurements from that system in an optimal fashion. We demonstrate the benefits obtainable from data assimilation with a dam break flume simulation in which a shallow-water equation model is complemented with wave meter measurements. Data assimilation is conducted with a Variational Ensemble Kalman Filter (VEnKF) algorithm. The resu...

  12. Organizational assimilation of collaborative information technologies: Global comparisons

    OpenAIRE

    Bawja, Deepinder S.; Lewis, L. Floyd; Pervan, Graham; Lai, Vincent; Munkvold, Bjørn E.; Schwabe, Gerhard

    2007-01-01

    This paper reports on a global initiative to investigate the assimilation of collaborative information technologies (CITs) in task-oriented collaboration. The two classes of CITs explored include conferencing and groupware technologies. Based upon the level of technology access/availability and utilization, four assimilation states are identified. Data collected from 538 organizations in the US, Australia, Hong Kong, Norway, and Switzerland is mapped in the four CIT assimilation states. The r...

  13. Robust data assimilation using $L_1$ and Huber norms

    OpenAIRE

    Rao, Vishwas; Sandu, Adrian; Ng, Michael; Nino-Ruiz, Elias

    2015-01-01

    Data assimilation is the process to fuse information from priors, observations of nature, and numerical models, in order to obtain best estimates of the parameters or state of a physical system of interest. Presence of large errors in some observational data, e.g., data collected from a faulty instrument, negatively affect the quality of the overall assimilation results. This work develops a systematic framework for robust data assimilation. The new algorithms continue to produce good analyse...

  14. Data Assimilation in Forest Inventory: First Empirical Results

    OpenAIRE

    Mattias Nyström; Nils Lindgren; Jörgen Wallerman; Anton Grafström; Anders Muszta; Kenneth Nyström; Jonas Bohlin; Erik Willén; Johan E.S. Fransson; Sarah Ehlers; Håkan Olsson; Göran Ståhl

    2015-01-01

    Data assimilation techniques were used to estimate forest stand data in 2011 by sequentially combining remote sensing based estimates of forest variables with predictions from growth models. Estimates of stand data, based on canopy height models obtained from image matching of digital aerial images at six different time-points between 2003 and 2011, served as input to the data assimilation. The assimilation routines were built on the extended Kalman filter. The study was conducted in hemi-bor...

  15. Negative and Positive Assimilation By Prices and By Quantities

    OpenAIRE

    Barry R. Chiswick; Paul W. Miller

    2013-01-01

    This paper considers the labor market assimilation of immigrants in terms of earnings and employment (employment probability, unemployment probability, and hours worked per week). Using the 2006 Australian Census of Population and Housing the analyses are performed separately by gender, and separately by whether or not the origin is an English-speaking developed country (ESDC). Among men in general, 'negative assimilation' is found for immigrants from the ESDC, and positive assimilation for o...

  16. An Ensemble Algorithm Based Component for Geomagnetic Data Assimilation

    OpenAIRE

    Zhibin Sun and Weijia Kuang

    2015-01-01

    Geomagnetic data assimilation is one of the most recent developments in geomagnetic studies. It combines geodynamo model outputs and surface geomagnetic observations to provide more accurate estimates of the core dynamic state and provide accurate geomagnetic secular variation forecasting. To facilitate geomagnetic data assimilation studies, we develop a stand-alone data assimilation component for the geomagnetic community. This component is used to calculate the forecast error covariance mat...

  17. The effect of model errors in variational assimilation

    OpenAIRE

    Wergen, Werner

    2011-01-01

    A linearized, one-dimensional shallow water model is used to investigate the effect of model errors in four-dimensional variational assimilation. A suitable initialization scheme for variational assimilation is proposed. Introducing deliberate phase speed errors in the model, the results from variational assimilation are compared to standard analysis/forecast cycle experiments. While the latter draws to the data and reflects the model errors only in the datavoid areas, variational assimilatio...

  18. Assimilation of GNSS radio occultation observations in GRAPES

    OpenAIRE

    Liu, Y; Xue, J.

    2014-01-01

    This paper reviews the development of the global navigation satellite system (GNSS) radio occultation (RO) observations assimilation in the Global/Regional Assimilation and PrEdiction System (GRAPES) of China Meteorological Administration, including the choice of data to assimilate, the data quality control, the observation operator, the tuning of observation error, and the results of the observation impact experiments. The results indicate that RO data have a significantly ...

  19. Evaluation of an ensemble-based incremental variational data assimilation

    OpenAIRE

    Yang, Yin; Robinson, Cordelia; Heitz, Dominique; Mémin, Etienne

    2014-01-01

    In this work, we aim at studying ensemble based optimal control strategies for data assimilation. Such formulation nicely combines the ingredients of ensemble Kalman filters and variational data assimilation (4DVar). In the same way as variational assimilation schemes, it is formulated as the minimization of an objective function, but similarly to ensemble filter, it introduces in its objective function an empirical ensemble-based background-error covariance and works in an off-line smoothing...

  20. Satellite data assimilation to improve forecasts of volcanic ash concentrations

    OpenAIRE

    Fu, Guangliang; Lin, Hai-Xiang; Heemink, Arnold; SEGERS Arjo; Prata, Fred; Lu, Sha

    2016-01-01

    Data assimilation is a powerful tool that requires available observations to improve model forecast accuracy. Infrared satellite measurements of volcanic ash mass loadings are often used as input observations into the assimilation scheme. However, these satellite-retrieved data are often two-dimensional (2D), and cannot be easily combined with a three-dimensional (3D) volcanic ash model to continuously improve the volcanic ash state in a data assimilation system. By integrating available data...

  1. Negative and Positive Assimilation, Skill Transferability, and Linguistic Distance

    OpenAIRE

    Chiswick, Barry R; Paul W. Miller

    2012-01-01

    There are two complementary models of immigrants' economic and social adjustment - the positive assimilation model of Chiswick (1978, 1979), and the negative assimilation model of Chiswick and Miller (2011). The negative assimilation model is applicable for immigrants from countries that are very similar in terms of the transferability of skills, culture, and labor market institutions to the host country, and has been tested previously primarily using migration among the English-speaking deve...

  2. ASSIMILATION CHOICES AMONG IMMIGRANT FAMILIES: DOES SCHOOL CONTEXT MATTER?

    OpenAIRE

    Greenman, Emily

    2011-01-01

    This paper explores the relationship between social context, measured in terms of school characteristics, and the assimilation of immigrant adolescents. First, it develops a measure of assimilation based on comparing immigrant adolescents to native peers within the same school. Second, it investigates whether immigrant adolescents’ degree of assimilation varies systematically according to school SES. Third, it explores the role of parental and adolescent behavior in creating such variation. R...

  3. The negative assimilation of immigrants: a special case

    OpenAIRE

    Chiswick, Barry R; Paul W. Miller

    2008-01-01

    Research on the economic or labor market assimilation of immigrants has to date focused on the degree of improvement in their economic status with duration in the destination. The theoretical underpinning for this finding is the international transferability of skills. This paper addresses whether positive assimilation will be found if skills are very highly transferable internationally. It outlines the conditions for “negative” assimilation in the context of the traditional immigration assim...

  4. Assimilation Effects on Poverty Among Immigrants in Norway.

    OpenAIRE

    Galloway, Taryn Ann; Aaberge, Rolf

    2003-01-01

    This paper discusses the question of whether or not the high incidence of poverty among immigrants in Norway persists even after immigrants have been in the country for a long period, i.e. after they have had the opportunity to integrate and adapt their skills to the expectations in their new home. While similar to traditional studies of wage assimilation, a study of assimilation in relation to poverty propensity nevertheless measures something different than labor market assimilation, and th...

  5. Data Assimilation Cycling for Weather Analysis

    Science.gov (United States)

    Tran, Nam; Li, Yongzuo; Fitzpatrick, Patrick

    2008-01-01

    This software package runs the atmospheric model MM5 in data assimilation cycling mode to produce an optimized weather analysis, including the ability to insert or adjust a hurricane vortex. The program runs MM5 through a cycle of short forecasts every three hours where the vortex is adjusted to match the observed hurricane location and storm intensity. This technique adjusts the surrounding environment so that the proper steering current and environmental shear are achieved. MM5cycle uses a Cressman analysis to blend observation into model fields to get a more accurate weather analysis. Quality control of observations is also done in every cycle to remove bad data that may contaminate the analysis. This technique can assimilate and propagate data in time from intermittent and infrequent observations while maintaining the atmospheric field in a dynamically balanced state. The software consists of a C-shell script (MM5cycle.driver) and three FORTRAN programs (splitMM5files.F, comRegrid.F, and insert_vortex.F), and are contained in the pre-processor component of MM5 called "Regridder." The model is first initialized with data from a global model such as the Global Forecast System (GFS), which also provides lateral boundary conditions. These data are separated into single-time files using splitMM5.F. The hurricane vortex is then bogussed in the correct location and with the correct wind field using insert_vortex.F. The modified initial and boundary conditions are then recombined into the model fields using comRegrid.F. The model then makes a three-hour forecast. The three-hour forecast data from MM5 now become the analysis for the next short forecast run, where the vortex will again be adjusted. The process repeats itself until the desired time of analysis is achieved. This code can also assimilate observations if desired.

  6. Variational data assimilation using targetted random walks

    KAUST Repository

    Cotter, S. L.

    2011-02-15

    The variational approach to data assimilation is a widely used methodology for both online prediction and for reanalysis. In either of these scenarios, it can be important to assess uncertainties in the assimilated state. Ideally, it is desirable to have complete information concerning the Bayesian posterior distribution for unknown state given data. We show that complete computational probing of this posterior distribution is now within the reach in the offline situation. We introduce a Markov chain-Monte Carlo (MCMC) method which enables us to directly sample from the Bayesian posterior distribution on the unknown functions of interest given observations. Since we are aware that these methods are currently too computationally expensive to consider using in an online filtering scenario, we frame this in the context of offline reanalysis. Using a simple random walk-type MCMC method, we are able to characterize the posterior distribution using only evaluations of the forward model of the problem, and of the model and data mismatch. No adjoint model is required for the method we use; however, more sophisticated MCMC methods are available which exploit derivative information. For simplicity of exposition, we consider the problem of assimilating data, either Eulerian or Lagrangian, into a low Reynolds number flow in a two-dimensional periodic geometry. We will show that in many cases it is possible to recover the initial condition and model error (which we describe as unknown forcing to the model) from data, and that with increasing amounts of informative data, the uncertainty in our estimations reduces. © 2011 John Wiley & Sons, Ltd.

  7. Nitrogen uptake and assimilation by corn roots

    International Nuclear Information System (INIS)

    The site of nitrogen uptake in the apical root zone of corn was experimentally investigated. Two experiments were performed. The one is to see the assimilation of nitrate and ammonium and the effects of low temperature on it. The 4-day-old roots were treated with 15N-labelled inorganic nitrogen of 20 ppm N in 5 x 10-4M CaSO4 solution at 30 deg. C and 0 deg. C. The other is to see the nitrogen uptake at apical root zone and the utilization of newly absorbed nitrogen at the root top. The 4-day-old roots were transferred into 5 x 10-4M CaSO4 solution containing 15N-labelled ammonium nitrate of 40 ppm N. As a result, the effect of low temperature on the nitrogen uptake appeared to be more drastic in the case of nitrate than ammonium. The 15N content of amino acids indicates that ammonium is assimilated into amino acids even at 0 deg. C, but nitrate is not. The ammonium nitrogen seemed to be absorbed at both cell dividing and elongating zones. On the other hand, nitrate nitrogen seemed to be strongly absorbed at cell elongating zone. The nitrogen in the apical part may be supplied not only by direct absorption but also by translocation from the basal part. The clear difference was found in the utilization of nitrate and ammonium nitrogen at the root top when the root was elongating. This may be due to the difference of assimilation products of inorganic nitrogen. Newly absorbed ammonium nitrogen is more utilizable for the growth of root top than nitrate nitrogen. (Iwakiri, K.)

  8. Ionospheric data assimilation and forecasting during storms

    Science.gov (United States)

    Chartier, Alex T.; Matsuo, Tomoko; Anderson, Jeffrey L.; Collins, Nancy; Hoar, Timothy J.; Lu, Gang; Mitchell, Cathryn N.; Coster, Anthea J.; Paxton, Larry J.; Bust, Gary S.

    2016-01-01

    Ionospheric storms can have important effects on radio communications and navigation systems. Storm time ionospheric predictions have the potential to form part of effective mitigation strategies to these problems. Ionospheric storms are caused by strong forcing from the solar wind. Electron density enhancements are driven by penetration electric fields, as well as by thermosphere-ionosphere behavior including Traveling Atmospheric Disturbances and Traveling Ionospheric Disturbances and changes to the neutral composition. This study assesses the effect on 1 h predictions of specifying initial ionospheric and thermospheric conditions using total electron content (TEC) observations under a fixed set of solar and high-latitude drivers. Prediction performance is assessed against TEC observations, incoherent scatter radar, and in situ electron density observations. Corotated TEC data provide a benchmark of forecast accuracy. The primary case study is the storm of 10 September 2005, while the anomalous storm of 21 January 2005 provides a secondary comparison. The study uses an ensemble Kalman filter constructed with the Data Assimilation Research Testbed and the Thermosphere Ionosphere Electrodynamics General Circulation Model. Maps of preprocessed, verticalized GPS TEC are assimilated, while high-latitude specifications from the Assimilative Mapping of Ionospheric Electrodynamics and solar flux observations from the Solar Extreme Ultraviolet Experiment are used to drive the model. The filter adjusts ionospheric and thermospheric parameters, making use of time-evolving covariance estimates. The approach is effective in correcting model biases but does not capture all the behavior of the storms. In particular, a ridge-like enhancement over the continental USA is not predicted, indicating the importance of predicting storm time electric field behavior to the problem of ionospheric forecasting.

  9. Open-nucleus breeding strategies compared with population-wide positive assortative mating: I. Equal distribution of testing efforts.

    Science.gov (United States)

    Lstibůrek, M; Mullin, T J; Lindgren, D; Rosvall, O

    2004-10-01

    Positive assortative mating (PAM) can enhance the additive genetic variance in a breeding population(BP). This increases the potential for gains in the production population (PP, selected subset of the BP) for recurrent selection programs in forest trees. The assortment of mates can be either: (1) by individual tree rank across the whole BP (PAM), or (2) trees of similar rank can be merged into larger hierarchical groups and then mated randomly within group ("open"-nucleus breeding,NB). The objective of this study was to compare PAM and NB in quantitative terms. The NB simulation model assumed two tiers (nucleus, main) with unrestricted migration between the tiers. Clonal tests were used to predict breeding values and test resources per mate were kept constant for all mates. Both gain and diversity were combined into a single selection criterion, "group-merit selection." Alternatives were compared over five breeding cycles by considering genetic gain and diversity in a selected PP established in a seed orchard. The assortment of mates in both alternatives enhanced additive variance and increased the additive effect in the BP, leading to additional gain in the PP. Gains generated under PAM always exceeded gains under NB. Thus, the main message from this study is that PAM in both the short- and long-term results in more gain at any target level of diversity in the PP (the breeder's target) than is achieved by the NB alternative. The optimum size of the nucleus varies with the desired level of seed orchard diversity. At lower target diversity, smaller nucleus sizes are favorable, while larger sizes result in more gain when seed orchard diversity is considered more important.

  10. Development of a data assimilation algorithm

    DEFF Research Database (Denmark)

    Thomsen, Per Grove; Zlatev, Zahari

    2008-01-01

    efficiently observations in a large-scale model (for example, in order to obtain more reliable initial values). Variational data assimilation techniques are based on a combination of three very important components • numerical methods for solving differential equations, • splitting procedures....... Modules from a particular large-scale mathematical model, the Unified Danish Eulerian Model (UNI-DEM), are used in the experiments. The mathematical background of UNI-DEM is discussed in [V.N. Alexandrov,W. Owczarz, P.G. Thomsen, Z. Zlatev, Parallel runs of a large air pollution model on a grid of Sun...

  11. Effective actions for statistical data assimilation

    International Nuclear Information System (INIS)

    Data assimilation is a problem in estimating the fixed parameters and state of a model of an observed dynamical system as it receives inputs from measurements passing information to the model. Using methods developed in statistical physics, we present effective actions and equations of motion for the mean orbits associated with the temporal development of a dynamical model when it has errors, there is uncertainty in its initial state, and it receives information from noisy measurements. If there are statistical dependences among errors in the measurements they can be included in this approach.

  12. Healthy snacks at the checkout counter: A lab and field study on the impact of shelf arrangement and assortment structure on consumer choices

    Directory of Open Access Journals (Sweden)

    van Kleef Ellen

    2012-12-01

    Full Text Available Abstract Background The essence of nudging is to adapt the environment in which consumers make decisions to help them make better choices, without forcing certain outcomes upon them. To determine how consumers can effectively be guided to select healthier snacks, we examine the effect of manipulating the assortment structure and shelf layout of an impulse display including both healthy and unhealthy snacks near the checkout counter of a canteen. Methods Both a lab and field study applied a two-factor experimental design manipulating snack offerings both in an on-screen choice environment and a natural environment (hospital staff restaurant. Shelf arrangement (i.e. accessibility was altered by putting healthy snacks at higher shelves versus lower shelves. Assortment structure (i.e. availability was altered by offering an assortment that either included 25% or 75% healthy snacks. Participants in the lab study (n = 158 made a choice from a shelf display. A brief survey following snack selection asked participants to evaluate the assortment and their choice. The field experiment took place in a hospital canteen. Daily sales data were collected for a period of four weeks. On completion of the field study, employees (n = 92 filled out a questionnaire about all four displays and rated their attractiveness, healthiness and perceived freedom of choice. Results The lab study showed a higher probability of healthy snack choice when 75% of the assortment consisted of healthy snacks compared to conditions with 25% healthy snack assortments, even though choices were not rated less satisfying or more restrictive. Regarding shelf display location of healthy snacks, no significant differences were observed. There was also no significant shelf arrangement by assortment structure interactive effect. The field study replicated these findings, in that this assortment structure led to higher sales of healthy snacks. Sales of unhealthy and total snacks were

  13. On optimization of data assimilation in the HBM -circulation model

    OpenAIRE

    VÀhÀ-Piikkiö, Olga

    2015-01-01

    The purpose of this study is to develop a method for optimizing the data assimilation system of the HIROMB-BOOS -model at the Finnish Meteorological Institute by finding an optimal time interval and an optimal grid for the data assimilation. This is needed to balance the extra time the data assimilation adds to the runtime of the model and the improved accuracy it provides. Data assimilation is the process of combining observations with a numerical model to improve the accuracy of the mod...

  14. Development of airborne remote sensing data assimilation system

    International Nuclear Information System (INIS)

    In this paper, an airborne remote sensing data assimilation system for China Airborne Remote Sensing System is introduced. This data assimilation system is composed of a land surface model, data assimilation algorithms, observation data and fundamental parameters forcing the land surface model. In this data assimilation system, Variable Infiltration Capacity hydrologic model is selected as the land surface model, which also serves as the main framework of the system. Three-dimensional variation algorithm, four-dimensional variation algorithms, ensemble Kalman filter and Particle filter algorithms are integrated in this system. Observation data includes ground observations and remotely sensed data. The fundamental forcing parameters include soil parameters, vegetation parameters and the meteorological data

  15. Spatial dependence of color assimilation by the watercolor effect

    OpenAIRE

    Devinck, Frédéric; Delahunt, Peter B.; Hardy, Joseph L.; Spillmann, Lothar; Werner, John S.

    2006-01-01

    Color assimilation with bichromatic contours was quantified for spatial extents ranging from von Bezold-type color assimilation to the watercolor effect. The magnitude and direction of assimilative hue change was measured as a function of the width of a rectangular stimulus. Assimilation was quantified by hue cancellation. Large hue shifts were required to null the color of stimuli ≤ 9.3 min of arc in width, with an exponential decrease for stimuli increasing up to 7.4 deg. When stimuli were ...

  16. Aerodynamic Modeling with Heterogeneous Data Assimilation and Uncertainty Quantification Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Clear Science Corp. proposes to develop an aerodynamic modeling tool that assimilates data from different sources and facilitates uncertainty quantification. The...

  17. Application of altimetry data assimilation on mesoscale eddies simulation

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    Mesoscale eddy plays an important role in the ocean circulation. In order to improve the simulation accuracy of the mesoscale eddies, a three-dimensional variation (3DVAR) data assimilation system called Ocean Variational Analysis System (OVALS) is coupled with a POM model to simulate the mesoscale eddies in the Northwest Pacific Ocean. In this system, the sea surface height anomaly (SSHA) data by satellite altimeters are assimilated and translated into pseudo temperature and salinity (T-S) profile data. Then, these profile data are taken as observation data to be assimilated again and produce the three-dimensional analysis T-S field. According to the characteristics of mesoscale eddy, the most appropriate assimilation parameters are set up and testified in this system. A ten years mesoscale eddies simulation and comparison experiment is made, which includes two schemes: assimilation and non-assimilation. The results of comparison between two schemes and the observation show that the simulation accuracy of the assimilation scheme is much better than that of non-assimilation, which verified that the altimetry data assimilation method can improve the simulation accuracy of the mesoscale dramatically and indicates that it is possible to use this system on the forecast of mesoscale eddies in the future.

  18. 7. national sittings on household and assimilated wastes; 7. assises nationales des dechets menagers et assimiles

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2002-07-01

    This publication brings together several press releases written at the occasion of the 7. national sittings on household and assimilated wastes (Agen (France), September 10-11, 2002), by responsibles of national organizations, associations, companies and local authorities involved in the management and processing of municipal wastes. (J.S.)

  19. First assimilations of COSMIC radio occultation data into the Electron Density Assimilative Model (EDAM

    Directory of Open Access Journals (Sweden)

    M. J. Angling

    2008-02-01

    Full Text Available Ground based measurements of slant total electron content (TEC can be assimilated into ionospheric models to produce 3-D representations of ionospheric electron density. The Electron Density Assimilative Model (EDAM has been developed for this purpose. Previous tests using EDAM and ground based data have demonstrated that the information on the vertical structure of the ionosphere is limited in this type of data. The launch of the COSMIC satellite constellation provides the opportunity to use radio occultation data which has more vertical information. EDAM assimilations have been run for three time periods representing quiet, moderate and disturbed geomagnetic conditions. For each run, three data sets have been ingested – only ground based data, only COSMIC data and both ground based and COSMIC data. The results from this preliminary study show that both ground and space based data are capable of improving the representation of the vertical structure of the ionosphere. However, the analysis is limited by the incomplete deployment of the COSMIC constellation and the use of auto-scaled ionosonde data. The first of these can be addressed by repeating this type of study once full deployment has been achieved. The latter requires the manual scaling of ionosonde data; ideally an agreed data set would be scaled and made available to the community to facilitate comparative testing of assimilative models.

  20. Continuous data assimilation with stochastically noisy data

    International Nuclear Information System (INIS)

    We analyse the performance of a data-assimilation algorithm based on a linear feedback control when used with observational data that contains measurement errors. Our model problem consists of dynamics governed by the two-dimensional incompressible Navier–Stokes equations, observational measurements given by finite volume elements or nodal points of the velocity field and measurement errors which are represented by stochastic noise. Under these assumptions, the data-assimilation algorithm consists of a system of stochastically forced Navier–Stokes equations. The main result of this paper provides explicit conditions on the observation density (resolution) which guarantee explicit asymptotic bounds, as the time tends to infinity, on the error between the approximate solution and the actual solutions which is corresponding to these measurements, in terms of the variance of the noise in the measurements. Specifically, such bounds are given for the limit supremum, as the time tends to infinity, of the expected value of the L2-norm and of the H1 Sobolev norm of the difference between the approximating solution and the actual solution. Moreover, results on the average time error in mean are stated. (paper)

  1. Phosphorus stress effects on assimilation of nitrate

    International Nuclear Information System (INIS)

    An experiment was conducted to investigate alterations in uptake and assimilation of NO3- by phosphorus-stressed plants. Young tobacco plants (Nicotiana tabacum [L.], cv NC 2326) growing in solution culture were derived of an external phosphorus (P) supply for 12 days. On selected days, plants were exposed to 15NO3- during the 12 hour light period to determine changes in NO3- assimilation as the P deficiency progressed. Decreased whole-plant growth was evident after 3 days of P deprivation and became more pronounced with time, but root growth was unaffected until after day 6. Uptake of 15NO3- per gram root dry weight and translocation of absorbed 15NO3- out of the root were noticeably restricted in -P plants by day 3, and effects on both increased in severity with time. Whole-plant reduction of 15NO3- and 15N incorporation into insoluble reduced-N in the shoot decreased after day 3. Although the P limitation was associated with a substantial accumulation of amino acids in the shoot, there was no indication of excessive accumulation of soluble reduced-15N in the shoot during the 12 hour 15NO3- exposure periods. The results indicate that alterations in NO3- transport processes in the root system are the primary initial responses limiting synthesis of shoot protein in P-stressed plants. Elevated amino acid levels evidently are associated with enhanced degradation of protein rather than inhibition of concurrent protein synthesis

  2. Using data assimilation for systematic model improvement

    Science.gov (United States)

    Lang, Matthew S.; van Leeuwen, Peter Jan; Browne, Phil

    2016-04-01

    In Numerical Weather Prediction parameterisations are used to simulate missing physics in the model. These can be due to a lack of scientific understanding or a lack of computing power available to address all the known physical processes. Parameterisations are sources of large uncertainty in a model as parameter values used in these parameterisations cannot be measured directly and hence are often not well known, and the parameterisations themselves are approximations of the processes present in the true atmosphere. Whilst there are many efficient and effective methods for combined state/parameter estimation in data assimilation, such as state augmentation, these are not effective at estimating the structure of parameterisations. A new method of parameterisation estimation is proposed that uses sequential data assimilation methods to estimate errors in the numerical models at each space-time point for each model equation. These errors are then fitted to predetermined functional forms of missing physics or parameterisations, that are based upon prior information. The method picks out the functional form, or that combination of functional forms, that bests fits the error structure. The prior information typically takes the form of expert knowledge. We applied the method to a one-dimensional advection model with additive model error, and it is shown that the method can accurately estimate parameterisations, with consistent error estimates. It is also demonstrated that state augmentation is not successful. The results indicate that this new method is a powerful tool in systematic model improvement.

  3. Data Assimilation by delay-coordinate nudging

    Science.gov (United States)

    Pazo, Diego; Lopez, Juan Manuel; Carrassi, Alberto

    2016-04-01

    A new nudging method for data assimilation, delay-coordinate nudging, is presented. Delay-coordinate nudging makes explicit use of present and past observations in the formulation of the forcing driving the model evolution at each time-step. Numerical experiments with a low order chaotic system show that the new method systematically outperforms standard nudging in different model and observational scenarios, also when using an un-optimized formulation of the delay-nudging coefficients. A connection between the optimal delay and the dominant Lyapunov exponent of the dynamics is found based on heuristic arguments and is confirmed by the numerical results, providing a guideline for the practical implementation of the algorithm. Delay-coordinate nudging preserves the easiness of implementation, the intuitive functioning and the reduced computational cost of the standard nudging, making it a potential alternative especially in the field of seasonal-to-decadal predictions with large Earth system models that limit the use of more sophisticated data assimilation procedures.

  4. Assimilative Mapping of Interhemispheric Polar Ionospheric Electrodynamics

    Science.gov (United States)

    Matsuo, T.; Richmond, A. D.; Knipp, D. J.; McGranaghan, R. M.

    2015-12-01

    The Earth's main magnetic field is asymmetric between hemispheres due to its non-dipolar component, leading to various hemispherical differences in the coupling among the solar wind, magnetosphere and ionosphere. Manifestation of the asymmetric coupling through different electrodynamic parameters reported in past studies is considerably diverse. To fill the gap in our current understanding, obtained so far by analyzing individual parameters separately and comparing statistical behaviors of the parameters, we quantify the degree of instantaneous inter-hemispheric imbalance of electromagnetic energy deposition (Poynting flux), field-aligned currents, and convection electric fields though global and self-consistent analysis of electrodynamic variables at both polar regions, by means of data assimilation. Inter-hemispheric assimilative maps of different high-latitude electrodynamical parameters are obtained from simultaneous analysis of multiple types of space-based and ground-based observations made available though the AMPERE, SuperDARN, SuperMAG and DMSP programs with rigorous consideration of the uncertainty associated with each observation.

  5. Hormonal control of sulfate uptake and assimilation.

    Science.gov (United States)

    Koprivova, Anna; Kopriva, Stanislav

    2016-08-01

    Plant hormones have a plethora of functions in control of plant development, stress response, and primary metabolism, including nutrient homeostasis. In the plant nutrition, the interplay of hormones with responses to nitrate and phosphate deficiency is well described, but relatively little is known about the interaction between phytohormones and regulation of sulfur metabolism. As for other nutrients, sulfate deficiency results in modulation of root architecture, where hormones are expected to play an important role. Accordingly, sulfate deficiency induces genes involved in metabolism of tryptophane and auxin. Also jasmonate biosynthesis is induced, pointing to the need of increase the defense capabilities of the plants when sulfur is limiting. However, hormones affect also sulfate uptake and assimilation. The pathway is coordinately induced by jasmonate and the key enzyme, adenosine 5'-phosphosulfate reductase, is additionally regulated by ethylene, abscisic acid, nitric oxid, and other phytohormones. Perhaps the most intriguing link between hormones and sulfate assimilation is the fact that the main regulator of the response to sulfate starvation, SULFATE LIMITATION1 (SLIM1) belongs to the family of ethylene related transcription factors. We will review the current knowledge of interplay between phytohormones and control of sulfur metabolism and discuss the main open questions. PMID:26810064

  6. An ionospheric assimilation model along a meridian plane

    Science.gov (United States)

    Le, Huijun; Liu, Libo; Ren, Zhipeng; Hu, Lianhuan; Chen, Yiding; Wan, Weixing

    2016-07-01

    In this paper, we developed a two-dimensional ionospheric assimilation model that assimilates the observations of peak electron density of F2-layer (NmF2) and the peak height of F2-layer (hmF2) derived from five ionosonde stations along the 120°E meridian, using three-dimensional variation techniques (3DVAR) based on a physics-based ionosphere theoretical model. The assimilation system can well produce the assimilated results along the 120°E meridian plane by using the data of NmF2 and hmF2 at five ionosonde stations from Mohe (52.0°N) to Sanya (18.3°N). The root mean square error (RMSE) between the analysis results of the assimilation model and the ionosonde observations is much lower than that between the results from international reference ionosphere (IRI) and the ionosonde observations. In addition, we carried out the assimilation test by taking the IRI results as the observations to check the assimilated results in the regions without observations. The assimilated result in the southern hemisphere (RMSE=0.29) is much worse than that in the northern hemisphere (RMSE=0.10) because no observations in the southern hemisphere were used. If the data derived from the four ionosonde stations in Australia are used, the assimilated result in the southern hemisphere would be much more accurate. In addition to NmF2 and hmF2, the assimilation model can also adjust the total electron content (TEC). The RMSE between the TEC after assimilation and the observed GPS TEC is much lower than that between the TEC from the IRI model and the observed GPS TEC.

  7. FISH detection of ribosomal cistrons and assortment-distortion for X and B chromosomes in Dichroplus pratensis (Acrididae).

    Science.gov (United States)

    Bidau, C J; Rosato, M; Martí, D A

    2004-01-01

    Assortment-distortion with respect to the X and NOR activity of a rare mitotically stable B chromosome (B(N)), was examined in 16 males of Dichroplus pratensis (Acrididae: Melanoplinae) from Argentine populations. In 1B individuals, the X and B associate preferentially during prophase I reaching a maximum level of association at zygotene. Frequency of X/B association remains relatively high up to diplotene-diakinesis and decreases steeply towards metaphase I. The percent X/B association at each stage is positively influenced by association at the previous stage, and interindividual variability in X/B association decreases as the frequency of association increases. Both chromosomes tended to preferentially orientate toward the same pole at MI (mean ratio of 16 individuals, 1.50:1) which determined an excess of XB and 00 second spermatocytes over X0 and 0B ones (1.39:1). No significant differences occurred between the MI, AI and MII assortment ratios. Fluorescent in situ hybridisation (FISH) confirmed that the B chromosome carries ribosomal genes and helped to establish that, during spermiogenesis, both the B and the normal NOR-bearing chromosome (S8) are clustered near the centriole adjunct region of spermatids. However, FISH failed to reveal the existence of inactive ribosomal cistrons in the X chromosome, as previously suggested, thus providing no support to a simple origin of the B from the X.

  8. 基于HVI检验数据的配棉方法%Cotton assorting based on HVI data

    Institute of Scientific and Technical Information of China (English)

    石洋; 张得昆; 徐玫

    2011-01-01

    利用公检棉花的HVI数据对棉纺企业配棉方法进行指导,达到优棉优用、稳定质量、节约资源、降低成本的目的.通过分析公检棉花各项数据指标和棉纺企业配棉指标的关系,以公检棉花的HVI数据为基础,根据配棉原理建立配棉数学模型,把配棉数学模型转化为标准的线性方程组,利用计算机求解方程组,完成对配棉模型的求解.通过对配棉方案进行优化,使棉纺企业更加合理地利用棉花资源.%The relationship between the objective fair detection data and cotton assorting indicators is analyzed. Taking HVI data as the basis,the mathematical model of cotton assorting is set up,then it is changed to standard system of linear equations,finally,the system of linear equations is solved by computer. The optimized cotton as-soring plan provides a reasonable way for cotton bales management and processing.

  9. Cotton Assorting Optimized Model Based on HVI Data and Its Application%基于HVI数据的配棉优选模型及应用研究

    Institute of Scientific and Technical Information of China (English)

    邱兆宝

    2012-01-01

    研究基于HVI数据的配棉方案优选模型的创建方法及应用效果.以HVI数据为基础,配棉技术标准为依据,运用系统工程的思想和方法,遵循配棉原则,利用较少的定量信息使决策的思维过程数学化,从而为多目标、多准则的配棉问题提供比较简便的决策方法.模型的求解采用隐枚举法,有效地解决了非线性目标整数规划配棉问题.认为:配棉方案优选模型与配棉方案的评价方法,可作为棉纺质量工艺专家指导系统的组成部分.%Establish method and application effect of cotton assorting optimized model based on HVI data were researched. HVI data were taken as base, technology standard of cotton assorting were selected as foundation, ideas and method of system engineering was used. Principle of cotton assorting should be followed. Decision-making process of thinking could be mathematical by using less quantitative information, so decision method of cotton assorting problems with multi-objective and multi criteria can be provided. Implicit enumeration was used for model solve,cotton assorting problems of nonlinear objective integer programming can be solved effectively. It is considered that the cotton assorting optimization model and evaluation methods could be the part of cotton spinning processing expert guide system.

  10. An adaptive ensemble Kalman filter for soil moisture data assimilation

    Science.gov (United States)

    In a 19-year twin experiment for the Red-Arkansas river basin we assimilate synthetic surface soil moisture retrievals into the NASA Catchment land surface model. We demonstrate how poorly specified model and observation error parameters affect the quality of the assimilation products. In particul...

  11. A Cross-Linguistic Examination of Assimilation Context Effects

    Science.gov (United States)

    Gow, David W. Jr.; Im, Aaron M.

    2004-01-01

    Language-specific phonological processes routinely affect the pronunciation of words spoken in context, but do not appear to interfere with spoken word recognition. Five experiments are presented in which native and non-speakers of Hungarian and Korean monitored for segments in assimilated and non-assimilated control contexts related to…

  12. Chemical Data Assimilation &Optimized Earth Observation

    Science.gov (United States)

    Lary, D.

    2003-04-01

    Issues such as ozone depletion, acid rain, and photochemical smog are all of considerable environmental importance. These issues are studied using the dual approach of observations and numerical modelling. In making balanced assessments of these issues it is vital to make the best use of all the information available to us, both theoretical and observational. This is a non-trivial task. The technique of "data assimilation" is a powerful tool which allows us to address this issue. It is revolutionising the way we can study atmospheric chemistry. Data assimilation allows us to simultaneously make good use of however many observations are available to us, our theoretical understanding, and any apriori information we have, within a mathematical framework. It even allows us to infer information about chemical constituents which are not observed. It is a technique which is set to grow in importance. It is also applicable to any system for which we have both observations, a deterministic model, and estimates of uncertainty. Such applications could be from laboratory kinetics to metabolic pathways. Looking ahead we can envision Data assimilation as part of a Optimized Earth Observation System by developing a dynamic data retrieval control system. The dynamic data retrieval control system will dynamically adapt the what, where, and when for the observations made in an online fashion to maximize information content, minimize uncertainty in characterizing the system’s state vector, and minimize both the required storage and data processing time for a given observation capability (with the possibility of even directing unmanned sub-orbital platforms, drones, to make additional observations). This is particularly desirable to facilitate the dynamic tracking of evolving sharp gradients, for example, those in chemical tracer fields often located at the polar vortex edge, the tropopause and the day-night division. The basic idea is the desire for symbiotic communication to

  13. SST data assimilation experiments using an adaptive variational method

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    An adaptive variational data assimilation method is proposed by Zhu and Kamachi[1]. This method can adaptively adjust the model state without knowing explicitly the model error covariance matrix. The method enables very flexible ways to form some reduced order problems. A proper reduced order problem not only reduces computational burden but also leads to corrections that are more consistent with the model dynamics that trends to produce better forecast. These features make the adaptive variational method a good candidate for SST data assimilation because the model error of an ocean model is usually difficult to estimate. We applied this method to an SST data assimilation problem using the LOTUS data sets and an ocean mixed layer model (Mellor-Yamada level 2.5). Results of assimilation experiments showed good skill of improvement subsurface temperatures by assimilating surface observation alone.

  14. DART: New Research Using Ensemble Data Assimilation in Geophysical Models

    Science.gov (United States)

    Anderson, Jeffrey; Raeder, Kevin; Hoar, Tim; Collins, Nancy; Romine, Glen; Barre, Jerome; Gaubert, Benjamin; Arellano, Ave; Wuerth, Stephanie

    2016-04-01

    The Data Assimilation Research Testbed (DART) is a community facility for ensemble data assimilation developed and supported by the National Center for Atmospheric Research. DART provides a comprehensive suite of software, documentation, examples and tutorials that can be used for ensemble data assimilation research, operations, and education. Scientists and software engineers from the Data Assimilation Research Section at NCAR are available to actively support DART users who want to use existing DART products or develop their own new applications. Current DART users range from university professors teaching data assimilation, to individual graduate students working with simple models, through national laboratories doing operational prediction with large state-of-the-art models. DART runs efficiently on many computational platforms ranging from laptops through thousands of cores on the newest supercomputers. This poster focuses on several recent research activities using DART with geophysical models: 1). Using CAM/DART to understand whether OCO-2 Total Precipitable Water observations can be useful in numerical weather prediction. 2). Impacts of the synergistic use of Infra-red CO retrievals (MOPITT, IASI) in CAMCHEM/DART assimilations. 3). Assimilation and Analysis of Observations of Amazonian Biomass Burning Emissions by MOPITT (aerosol optical depth), MODIS (carbon monoxide) and MISR (plume height). 4). Long term evaluation of the chemical response of MOPITT-CO assimilation in CAM-CHEM/DART OSSEs for satellite planning and emission inversion capabilities. 5). Improved forward observation operators for land models that have multiple land use/land cover segments in a single grid cell, enabling studies of the inherent variability in a single gridcell. Future enhancements are also discussed: 1). The CICE component of the Community Earth System Model will be added to the existing suite of components, which can be used for data assimilation. 2). Fully coupled

  15. The dynamic radiation environment assimilation model (DREAM)

    Energy Technology Data Exchange (ETDEWEB)

    Reeves, Geoffrey D [Los Alamos National Laboratory; Koller, Josef [Los Alamos National Laboratory; Tokar, Robert L [Los Alamos National Laboratory; Chen, Yue [Los Alamos National Laboratory; Henderson, Michael G [Los Alamos National Laboratory; Friedel, Reiner H [Los Alamos National Laboratory

    2010-01-01

    The Dynamic Radiation Environment Assimilation Model (DREAM) is a 3-year effort sponsored by the US Department of Energy to provide global, retrospective, or real-time specification of the natural and potential nuclear radiation environments. The DREAM model uses Kalman filtering techniques that combine the strengths of new physical models of the radiation belts with electron observations from long-term satellite systems such as GPS and geosynchronous systems. DREAM includes a physics model for the production and long-term evolution of artificial radiation belts from high altitude nuclear explosions. DREAM has been validated against satellites in arbitrary orbits and consistently produces more accurate results than existing models. Tools for user-specific applications and graphical displays are in beta testing and a real-time version of DREAM has been in continuous operation since November 2009.

  16. Recent immigration and studies of ethnic assimilation.

    Science.gov (United States)

    Taeuber, A F; Taeuber, K E

    1967-06-01

    Studies of ethnic assimilation are frequently based upon status comparisons between the foreign born and their "children," the second generation. The assumption that recent immigration has been negligible and that the foreign born represent a closed population is implicit in that procedure. However, analysis of official statistics indicates that immigrants who arrived since World War II now comprise a substantial share of the foreign-born population, while the foreign born who arrived before quota restrictions are rapidly being depleted by mortality. Recent immigrants, as intended by quota legislation, are of much higher socioeconomic status than immigrants who arrived before World War 1. Hence, characteristics of both recent immigrants and earlier arrivals are confounded in data for the foreign-born population. Existing data do not permit rigorous assessment of this confusion or adequate control for it. This paper suggests that tabulations of the foreign born by "year of arrival" would improve the sociological utility of data for ethnic groups.

  17. Ensemble Data Assimilation Without Ensembles: Methodology and Application to Ocean Data Assimilation

    Science.gov (United States)

    Keppenne, Christian L.; Rienecker, Michele M.; Kovach, Robin M.; Vernieres, Guillaume

    2013-01-01

    Two methods to estimate background error covariances for data assimilation are introduced. While both share properties with the ensemble Kalman filter (EnKF), they differ from it in that they do not require the integration of multiple model trajectories. Instead, all the necessary covariance information is obtained from a single model integration. The first method is referred-to as SAFE (Space Adaptive Forecast error Estimation) because it estimates error covariances from the spatial distribution of model variables within a single state vector. It can thus be thought of as sampling an ensemble in space. The second method, named FAST (Flow Adaptive error Statistics from a Time series), constructs an ensemble sampled from a moving window along a model trajectory. The underlying assumption in these methods is that forecast errors in data assimilation are primarily phase errors in space and/or time.

  18. Effects of sample density on the assimilation performance of an explicit four-dimensional variational data assimilation method

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    The concepts of sample sphere radius and sample density are proposed in this paper to help illustrate that different vector transformations result in diverse sample density with the same sample ensemble, which finally affects their assimilation performance. Several numerical experiments using a onedimensional (1-D) soil water equation and synthetic observations are conducted to evaluate this new theory in land data assimilation.

  19. Improving information assimilation by modeling warfighter context

    Science.gov (United States)

    Zaientz, Jack D.; Wood, Scott D.; Hawkins, Robert L.

    2005-05-01

    In order to wage successful campaigns, the next generation of intelligence analysts and battle commanders will need to assimilate an enormous amount of information that will come from a wide range of heterogeneous data sources. Complicating this problem further is the fact that warfighters need to be able to manage information in an environment of rapidly changing events and priorities. The consequence of not addressing this problem, or not addressing it as effectively as hostile forces do, is a potential loss of assets, personnel, or tactical advantage. To design effective information displays there needs to be an extensible framework that models the warfighters context including characteristics of the information sources being displayed, the current Intelligence Surveillance Reconnaissance (ISR) picture or Common Operating Picture (COP), the warfighters current state and task, and the state of the information display. BINAH (Battlespace Information and Notification through Adaptive Heuristics) uses an agent-based modeling approach coupled with research into temporal and spatial reasoning, novel display management techniques, and development of a formal high-level language for describing model-based information configuration. The result is an information configuration pipeline designed to provide perceptual and cognitive analysis support to Air Force analysts engaged in Time-Critical Targeting target nomination. It has been integrated with the Air Force Research Laboratory's (AFRL) XML-based Joint Battlespace Infosphere (JBI) combat information management system and combines JBI delivered sensor data with a local user model and display strategies to configure a geospatial information display. The BINAH framework will provide a firm grounding for developing new C4ISR displays that maximize the ability of warfighters to assimilate the information presented.

  20. The Assimilation Process of Mexican Immigrants in New York City: From Assimilation to Integration

    OpenAIRE

    González Salazar, Ada Elvira

    2003-01-01

    This thesis is a study of the assimilation process of Mexican immigrants in New York City, taking as a case study the work of Tepeyac Association of New York. This case was chosen because Tepeyac Association has been able to mobilize the largest number of Mexican immigrants in that city, serving as a liaison between them and the City's social, economic and political life. The hypothesis is that Mexican immigrants' ideal relation to American life, as compared to that of earli...

  1. Incremental 4D-VAR assimilation scheme based on Lorenz model

    Institute of Scientific and Technical Information of China (English)

    WANG Xidong; XU Dongfeng; XU Xiaohua

    2008-01-01

    Four-dimensional variational(4D-VAR) data assimilation method is a perfect data assimilation solution in theory, but the compu- tational issue is quite difficult in operational implementation. The incremental 4D-VAR assimilation scheme is set up in order to re- duce the computational cost. It is shown that the accuracy of the observations, the length of the assimilation window and the choice of the first guess have an important influence on the assimilation outcome through the contrast experiment. Compared with the standard 4D-VAR assimilation scheme, the incremental 4D-VAR assimilation scheme shows its advantage in the computation speed through an assimilation experiment.

  2. Sensitivity of simulated terrestrial carbon assimilation and canopy transpiration to different stomatal conductance and carbon assimilation schemes

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Haishan [Nanjing University of Information Science and Technology, Key Laboratory of Meteorological Disaster of Ministry of Education, Nanjing (China); Georgia Institute of Technology, School of Earth and Atmospheric Sciences, Atlanta, GA (United States); Dickinson, Robert E. [Georgia Institute of Technology, School of Earth and Atmospheric Sciences, Atlanta, GA (United States); The University of Texas at Austin, Department of Geological Sciences, Austin, TX (United States); Dai, Yongjiu [Beijing Normal University, State Key Laboratory of Earth Surface Processes and Resource Ecology, School of Global Change and Earth System Science, Beijing (China); Zhou, Liming [Georgia Institute of Technology, School of Earth and Atmospheric Sciences, Atlanta, GA (United States)

    2011-03-15

    Accurate simulations of terrestrial carbon assimilation and canopy transpiration are needed for both climate modeling and vegetation dynamics. Coupled stomatal conductance and carbon assimilation (A - g{sub s}) models have been widely used as part of land surface parameterizations in climate models to describe the biogeophysical and biogeochemical roles of terrestrial vegetation. Differences in various A - g{sub s} schemes produce substantial differences in the estimation of carbon assimilation and canopy transpiration, as well as in other land-atmosphere fluxes. The terrestrial carbon assimilation and canopy transpiration simulated by two different representative A - g{sub s} schemes, a simple A-g{sub s} scheme adopted from the treatments of the NCAR model (Scheme I) and a two-big-leaf A - g{sub s} scheme newly developed by Dai et al. (J Clim 17:2281-2299, 2004) (Scheme II), are compared via some sensitivity experiments to investigate impacts of different A - g{sub s} schemes on the simulations. Major differences are found in the estimate of canopy carbon assimilation rate, canopy conductance and canopy transpiration between the two schemes, primarily due to differences in (a) functional forms used to estimate parameters for carbon assimilation sub-models, (b) co-limitation methods used to estimate carbon assimilation rate from the three limiting rates, and (c) leaf-to-canopy scaling schemes. On the whole, the differences in the scaling approach are the largest contributor to the simulation discrepancies, but the different methods of co-limitation of assimilation rate also impact the results. Except for a few biomes, the residual effects caused by the different parameter estimations in assimilation sub-models are relatively small. It is also noted that the two-leaf temperature scheme produces distinctly different sunlit and shaded leaf temperatures but has negligible impacts on the simulation of the carbon assimilation. (orig.)

  3. Assimilation of stratospheric ozone in the chemical transport model STRATAQ

    Directory of Open Access Journals (Sweden)

    B. Grassi

    2004-09-01

    Full Text Available We describe a sequential assimilation approach useful for assimilating tracer measurements into a three-dimensional chemical transport model (CTM of the stratosphere. The numerical code, developed largely according to Kha00, uses parameterizations and simplifications allowing assimilation of sparse observations and the simultaneous evaluation of analysis errors, with reasonable computational requirements. Assimilation parameters are set by using χ2 and OmF (Observation minus Forecast statistics. The CTM used here is a high resolution three-dimensional model. It includes a detailed chemical package and is driven by UKMO (United Kingdom Meteorological Office analyses. We illustrate the method using assimilation of Upper Atmosphere Research Satellite/Microwave Limb Sounder (UARS/MLS ozone observations for three weeks during the 1996 antarctic spring. The comparison of results from the simulations with TOMS (Total Ozone Mapping Spectrometer measurements shows improved total ozone fields due to assimilation of MLS observations. Moreover, the assimilation gives indications on a possible model weakness in reproducing polar ozone values during springtime.

  4. Complex networks generated by the Penna bit-string model: Emergence of small-world and assortative mixing

    Science.gov (United States)

    Li, Chunguang; Maini, Philip K.

    2005-10-01

    The Penna bit-string model successfully encompasses many phenomena of population evolution, including inheritance, mutation, evolution, and aging. If we consider social interactions among individuals in the Penna model, the population will form a complex network. In this paper, we first modify the Verhulst factor to control only the birth rate, and introduce activity-based preferential reproduction of offspring in the Penna model. The social interactions among individuals are generated by both inheritance and activity-based preferential increase. Then we study the properties of the complex network generated by the modified Penna model. We find that the resulting complex network has a small-world effect and the assortative mixing property.

  5. Left or right? Sources of political orientation: the roles of genetic factors, cultural transmission, assortative mating, and personality.

    Science.gov (United States)

    Kandler, Christian; Bleidorn, Wiebke; Riemann, Rainer

    2012-03-01

    In this study, we used an extended twin family design to investigate the influences of genetic and cultural transmission as well as different sources of nonrandom mating on 2 core aspects of political orientation: acceptance of inequality and rejecting system change. In addition, we studied the sources of phenotypic links between Big Five personality traits and political beliefs using self- and other reports. Data of 1,992 individuals (224 monozygotic and 166 dizygotic twin pairs, 92 unmatched twins, 530 spouses of twins, 268 fathers, and 322 mothers) were analyzed. Genetically informative analyses showed that political attitudes are genetically but not environmentally transmitted from parents to offspring and that a substantial proportion of this genetic variance can be accounted for by genetic variance in personality traits. Beyond genetic effects and genotypic assortative mating, generation-specific environmental sources act to increase twins' and spouses' resemblance in political beliefs. The results suggest multiple sources of political orientations in a modern democracy.

  6. Processing technology of assorted spiced rabbit meat%卤味兔肉加工工艺

    Institute of Scientific and Technical Information of China (English)

    陈兴; 盛本国; 王军锋; 李海龙; 严文慧

    2012-01-01

    阐述了卤味兔肉的加工工艺、操作关键点及质量要求,此加工工艺简化了传统的酱卤工艺,且卤香味与兔肉的结合,既去除了兔肉的腥膻味,也赋予了兔肉特色的卤香味。%The assorted spiced rabbit meat processing technology, operating key points and quality requirements were elaborated; using this processing technology could simplify the traditional sauce halogen and halogen technology, and combine the fragrance with rabbit meat, which not only removed fishy and sheepy smell of rabbit meat, but also gave the meat characteristic bittern flavor.

  7. Left or right? Sources of political orientation: the roles of genetic factors, cultural transmission, assortative mating, and personality.

    Science.gov (United States)

    Kandler, Christian; Bleidorn, Wiebke; Riemann, Rainer

    2012-03-01

    In this study, we used an extended twin family design to investigate the influences of genetic and cultural transmission as well as different sources of nonrandom mating on 2 core aspects of political orientation: acceptance of inequality and rejecting system change. In addition, we studied the sources of phenotypic links between Big Five personality traits and political beliefs using self- and other reports. Data of 1,992 individuals (224 monozygotic and 166 dizygotic twin pairs, 92 unmatched twins, 530 spouses of twins, 268 fathers, and 322 mothers) were analyzed. Genetically informative analyses showed that political attitudes are genetically but not environmentally transmitted from parents to offspring and that a substantial proportion of this genetic variance can be accounted for by genetic variance in personality traits. Beyond genetic effects and genotypic assortative mating, generation-specific environmental sources act to increase twins' and spouses' resemblance in political beliefs. The results suggest multiple sources of political orientations in a modern democracy. PMID:21988277

  8. Random length assortment of human and mouse T cell receptor for antigen alpha and beta chain CDR3.

    Science.gov (United States)

    Johnson, G; Wu, T T

    1999-10-01

    In view of the recently determined three-dimensional structures of complexes formed by the T cell receptor for antigen (TCR), the processed peptide and the MHC class I molecule, it is expected that the combined configuration formed by the third complementarity determining regions (CDR3) of TCR alpha and beta chains will be very restricted in size and shape due to the limited length variations of the processed peptides. Thus, the combined TCR alpha and beta chain CDR3 lengths should have a fairly narrow distribution. This feature can be due to the selective association of long alpha chain CDR3 with short beta chain CDR3 and vice versa or due to random assortment of alpha and beta chain CDR3 of even narrower length distribution. Based on existing translated amino acid sequence data, it has been found that the latter mechanism is responsible.

  9. Recent Developments in Helioseismic Analysis Methods and Solar Data Assimilation

    CERN Document Server

    Schad, Ariane; Duvall, Tom L; Roth, Markus; Vorontsov, Sergei V

    2016-01-01

    We review recent advances and results in enhancing and developing helioseismic analysis methods and in solar data assimilation. In the first part of this paper we will focus on selected developments in time-distance and global helioseismology. In the second part, we review the application of data assimilation methods on solar data. Relating solar surface observations as well as helioseismic proxies with solar dynamo models by means of the techniques from data assimilation is a promising new approach to explore and to predict the magnetic activity cycle of the Sun.

  10. Assimilation characteristics of vanadium ferroalloys in liquid steel

    International Nuclear Information System (INIS)

    The assimilation characteristics of various vanadium ferroalloys were identified in a ''dynamic way'' using the load cell technique. The ferrovanadium alloys which have a vanadium content less than 68 wt % belong to class 1 ferroalloys. They utilize a melting mechanism during their assimilation in liquid steel. The ferrovanadium alloys which have a vanadium content greater than 68 wt % belong to class 2 ferroalloys. These follow a dissolution mechanism during their assimilation in liquid steel. Their mass transfer kinetics is at least seven times slower than the previously mentioned ferrovanadium alloys

  11. Effect of food acclimation on assimilation efficiency of Calanus pacificus

    Energy Technology Data Exchange (ETDEWEB)

    Landry, M.R.; Hassett, R.P.; Fagerness, V.; Downs, J.; Lorenzen, C.J.

    1984-03-01

    A technique, based on quantitative conversion of chlorophyll a to pheophorbide during digestion, is described for determination of assimilation efficiencies of particle-feeding zooplankton. Calanus pacificus had assimilation efficiencies ranging from 68.5 to 85.4% for carbon and 73.9 to 92.5% for nitrogen. Assimilation efficiencies for copepods first acclimated to different food concentrations of Thalassiosira weissflogii and then fed at the same food level varied systematically, with animals acclimated to low food having higher efficiencies than animals acclimated to high food.

  12. Assimilative Learning with the Aid of Cognitive Maps

    Directory of Open Access Journals (Sweden)

    D. Läge

    2008-06-01

    Full Text Available Assimilative learning is understood asintegrating new information into existing knowledge orcognitive structures without restructuring the currentschema. If new information causes inconsistencies, cognitiveefforts are necessary to reorganize or to accommodate theold knowledge. Thus, assimilative learning is more efficientand economic. Nonetheless a stable and most notably acorrect memory representation which “spans” theknowledge space is essential. The current article highlightsthe logic of assimilative learning and shows how buildingelaborately a basic structure as well as the assimilativeintegration of new information can be eased with the aid ofcognitive maps. Such a didactical scenario can be easilyimplemented in the field of eLearning and thus, isadaptively and automatically supporting the learningprocess.

  13. Assortative mating and the reversal of gender inequality in education in europe: an agent-based model.

    Directory of Open Access Journals (Sweden)

    André Grow

    Full Text Available While men have always received more education than women in the past, this gender imbalance in education has turned around in large parts of the world. In many countries, women now excel men in terms of participation and success in higher education. This implies that, for the first time in history, there are more highly educated women than men reaching the reproductive ages and looking for a partner. We develop an agent-based computational model that explicates the mechanisms that may have linked the reversal of gender inequality in education with observed changes in educational assortative mating. Our model builds on the notion that individuals search for spouses in a marriage market and evaluate potential candidates based on preferences. Based on insights from earlier research, we assume that men and women prefer partners with similar educational attainment and high earnings prospects, that women tend to prefer men who are somewhat older than themselves, and that men prefer women who are in their mid-twenties. We also incorporate the insight that the educational system structures meeting opportunities on the marriage market. We assess the explanatory power of our model with systematic computational experiments, in which we simulate marriage market dynamics in 12 European countries among individuals born between 1921 and 2012. In these experiments, we make use of realistic agent populations in terms of educational attainment and earnings prospects and validate model outcomes with data from the European Social Survey. We demonstrate that the observed changes in educational assortative mating can be explained without any change in male or female preferences. We argue that our model provides a useful computational laboratory to explore and quantify the implications of scenarios for the future.

  14. Face-to-Face Sharing with Strangers and Altruistic Punishment of Acquaintances for Strangers: Young Adolescents Exhibit Greater Altruism than Adults

    Science.gov (United States)

    Hao, Jian; Yang, Yue; Wang, Zhiwen

    2016-01-01

    Young adolescents are generally considered to be self-absorbed. Studies indicate that they lack relevant general cognitive abilities, such as impulse control, that mature in early adulthood. However, their idealism may cause them to be more intolerant of unfair treatment to others and thus result in their engaging in more altruistic behavior. The present study aimed to clarify whether young adolescents are more altruistic than adults and thus indicate whether altruistic competence is domain-specific. One hundred 22 young adolescents and adults participated in a face-to-face, two-round, third-party punishment experiment. In each interaction group, a participant served as an allocator who could share money units with a stranger; another participant who knew the allocator could punish the acquaintance for the stranger. Participants reported their emotions after the first round, and at the end of the experiment, the participants justified their behavior in each round. The results indicated that the young adolescents both shared more and punished more than did the adults. Sharing was associated with a reference to fairness in the justifications, but altruistic punishment was associated with subsequent positive emotion. In sum, greater altruism in young adolescents compared to adults with mature cognitive abilities provides evidence of domain-specificity of altruistic competence. Moreover, sharing and altruistic punishment are related to specific cognitive and emotional mechanisms, respectively. PMID:27752246

  15. Assimilation of MODIS Snow Cover Through the Data Assimilation Research Testbed and the Community Land Model Version 4

    Science.gov (United States)

    Zhang, Yong-Fei; Hoar, Tim J.; Yang, Zong-Liang; Anderson, Jeffrey L.; Toure, Ally M.; Rodell, Matthew

    2014-01-01

    To improve snowpack estimates in Community Land Model version 4 (CLM4), the Moderate Resolution Imaging Spectroradiometer (MODIS) snow cover fraction (SCF) was assimilated into the Community Land Model version 4 (CLM4) via the Data Assimilation Research Testbed (DART). The interface between CLM4 and DART is a flexible, extensible approach to land surface data assimilation. This data assimilation system has a large ensemble (80-member) atmospheric forcing that facilitates ensemble-based land data assimilation. We use 40 randomly chosen forcing members to drive 40 CLM members as a compromise between computational cost and the data assimilation performance. The localization distance, a parameter in DART, was tuned to optimize the data assimilation performance at the global scale. Snow water equivalent (SWE) and snow depth are adjusted via the ensemble adjustment Kalman filter, particularly in regions with large SCF variability. The root-mean-square error of the forecast SCF against MODIS SCF is largely reduced. In DJF (December-January-February), the discrepancy between MODIS and CLM4 is broadly ameliorated in the lower-middle latitudes (2345N). Only minimal modifications are made in the higher-middle (4566N) and high latitudes, part of which is due to the agreement between model and observation when snow cover is nearly 100. In some regions it also reveals that CLM4-modeled snow cover lacks heterogeneous features compared to MODIS. In MAM (March-April-May), adjustments to snowmove poleward mainly due to the northward movement of the snowline (i.e., where largest SCF uncertainty is and SCF assimilation has the greatest impact). The effectiveness of data assimilation also varies with vegetation types, with mixed performance over forest regions and consistently good performance over grass, which can partly be explained by the linearity of the relationship between SCF and SWE in the model ensembles. The updated snow depth was compared to the Canadian Meteorological

  16. Hybrid Data Assimilation without Ensemble Filtering

    Science.gov (United States)

    Todling, Ricardo; Akkraoui, Amal El

    2014-01-01

    The Global Modeling and Assimilation Office is preparing to upgrade its three-dimensional variational system to a hybrid approach in which the ensemble is generated using a square-root ensemble Kalman filter (EnKF) and the variational problem is solved using the Grid-point Statistical Interpolation system. As in most EnKF applications, we found it necessary to employ a combination of multiplicative and additive inflations, to compensate for sampling and modeling errors, respectively and, to maintain the small-member ensemble solution close to the variational solution; we also found it necessary to re-center the members of the ensemble about the variational analysis. During tuning of the filter we have found re-centering and additive inflation to play a considerably larger role than expected, particularly in a dual-resolution context when the variational analysis is ran at larger resolution than the ensemble. This led us to consider a hybrid strategy in which the members of the ensemble are generated by simply converting the variational analysis to the resolution of the ensemble and applying additive inflation, thus bypassing the EnKF. Comparisons of this, so-called, filter-free hybrid procedure with an EnKF-based hybrid procedure and a control non-hybrid, traditional, scheme show both hybrid strategies to provide equally significant improvement over the control; more interestingly, the filter-free procedure was found to give qualitatively similar results to the EnKF-based procedure.

  17. Kimberlite ascent by assimilation-fuelled buoyancy.

    Science.gov (United States)

    Russell, James K; Porritt, Lucy A; Lavallée, Yan; Dingwell, Donald B

    2012-01-19

    Kimberlite magmas have the deepest origin of all terrestrial magmas and are exclusively associated with cratons. During ascent, they travel through about 150 kilometres of cratonic mantle lithosphere and entrain seemingly prohibitive loads (more than 25 per cent by volume) of mantle-derived xenoliths and xenocrysts (including diamond). Kimberlite magmas also reputedly have higher ascent rates than other xenolith-bearing magmas. Exsolution of dissolved volatiles (carbon dioxide and water) is thought to be essential to provide sufficient buoyancy for the rapid ascent of these dense, crystal-rich magmas. The cause and nature of such exsolution, however, remains elusive and is rarely specified. Here we use a series of high-temperature experiments to demonstrate a mechanism for the spontaneous, efficient and continuous production of this volatile phase. This mechanism requires parental melts of kimberlite to originate as carbonatite-like melts. In transit through the mantle lithosphere, these silica-undersaturated melts assimilate mantle minerals, especially orthopyroxene, driving the melt to more silicic compositions, and causing a marked drop in carbon dioxide solubility. The solubility drop manifests itself immediately in a continuous and vigorous exsolution of a fluid phase, thereby reducing magma density, increasing buoyancy, and driving the rapid and accelerating ascent of the increasingly kimberlitic magma. Our model provides an explanation for continuous ascent of magmas laden with high volumes of dense mantle cargo, an explanation for the chemical diversity of kimberlite, and a connection between kimberlites and cratons. PMID:22258614

  18. Assimilate partitioning in avocado, Persea americana

    Energy Technology Data Exchange (ETDEWEB)

    Finazzo, S.; Davenport, T.L.

    1986-04-01

    Assimilate partitioning is being studied in avocado, Persea americana cv. Millborrow in relation to fruit set. Single leaves on girdled branches of 10 year old trees were radiolabeled for 1 hr with 13..mu..Ci of /sup 14/CO/sub 2/. The source leaves were sampled during the experiment to measure translocation rates. At harvest the sink tissues were dissected and the incorporated radioactivity was measured. The translocation of /sup 14/C-labelled compounds to other leaves was minimal. Incorporation of label into fruitlets varied with the tissue and the stage of development. Sink (fruitlets) nearest to the labelled leaf and sharing the same phyllotaxy incorporated the most /sup 14/C. Source leaves for single non-abscising fruitlets retained 3X more /sup 14/C-labelled compounds than did source leaves for 2 or more fruitlets at 31 hrs. post-labelling. Export of label decreased appreciably when fruitlets abscised. If fruitlets abscised within 4 days of labeling then the translocation pattern was similar to the pattern for single fruitlets. If the fruitlet abscised later, the translocation pattern was intermediate between the single and double fruitlet pattern.

  19. Assimilate partitioning in avocado, Persea americana

    International Nuclear Information System (INIS)

    Assimilate partitioning is being studied in avocado, Persea americana cv. Millborrow in relation to fruit set. Single leaves on girdled branches of 10 year old trees were radiolabeled for 1 hr with 13μCi of 14CO2. The source leaves were sampled during the experiment to measure translocation rates. At harvest the sink tissues were dissected and the incorporated radioactivity was measured. The translocation of 14C-labelled compounds to other leaves was minimal. Incorporation of label into fruitlets varied with the tissue and the stage of development. Sink (fruitlets) nearest to the labelled leaf and sharing the same phyllotaxy incorporated the most 14C. Source leaves for single non-abscising fruitlets retained 3X more 14C-labelled compounds than did source leaves for 2 or more fruitlets at 31 hrs. post-labelling. Export of label decreased appreciably when fruitlets abscised. If fruitlets abscised within 4 days of labeling then the translocation pattern was similar to the pattern for single fruitlets. If the fruitlet abscised later, the translocation pattern was intermediate between the single and double fruitlet pattern

  20. Simplified aerosol modeling for variational data assimilation

    Directory of Open Access Journals (Sweden)

    F. Chevallier

    2009-06-01

    Full Text Available We have developed a simplified aerosol model together with its tangent linear and adjoint versions for variational assimilation of aerosol optical depth with the aim to optimize aerosol emissions over the globe. The model was derived from the general circulation model LMDz; it groups together the 24 aerosol species simulated in LMDz into 4 species, namely gaseous precursors, fine mode aerosols, coarse mode desert dust and coarse mode sea salt. The emissions have been kept as in the original model. Modifications, however, were introduced in the computation of aerosol optical depth and in the processes of sedimentation, dry and wet deposition and sulfur chemistry to ensure consistency with the new set of species and their composition.

    The simplified model successfully manages to reproduce the main features of the aerosol distribution in LMDz. Differences between the original and simplified models are mainly associated to the new deposition and sedimentation velocities consistent with the definition of species in the simplified model and the simplification of the sulfur chemistry. Furthermore, simulated aerosol optical depth remains within the variability of AERONET observations for all aerosol types and all sites throughout most of the year.

    Sensitivity analyses with the tangent linear version show that the simplified sulfur chemistry is the dominant process responsible for the strong non-linearity of the model.

  1. The assimilation of elements ingested by marine copepods

    International Nuclear Information System (INIS)

    The efficiency with which a variety of ingested elements (Ag, Am, C, Cd, P, S, Se, and Zn) were assimilated in marine calanoid copepods fed uniformly radiolabeled diatoms ranged from 0.9% for Am to 97.1% for Se. Assimilation efficiencies were directly related to the cytoplasmic content of the diatoms. This relation indicates that the animals obtained nearly all their nutrition from this source. The results suggest that these zooplankton, which have short gut residence times, have developed a gut lining and digestive strategy that provides for assimilation of only soluble material. Because the fraction of total cellular protein in the cytoplasm of the diatoms increased markedly with culture age, copepods feeding on senescent cells should obtain more protein than those feeding on rapidly dividing cells. Elements that are appreciably incorporated into algal cytoplasm and assimilated in zooplankton should be recycled in surface waters and have longer oceanic residence times than elements bound to cell surfaces

  2. Satellite Sounder Data Assimilation for Improving Alaska Region Weather Forecast

    Science.gov (United States)

    Zhu, Jiang; Stevens, E.; Zavodsky, B. T.; Zhang, X.; Heinrichs, T.; Broderson, D.

    2014-01-01

    Data assimilation has been demonstrated very useful in improving both global and regional numerical weather prediction. Alaska has very coarser surface observation sites. On the other hand, it gets much more satellite overpass than lower 48 states. How to utilize satellite data to improve numerical prediction is one of hot topics among weather forecast community in Alaska. The Geographic Information Network of Alaska (GINA) at University of Alaska is conducting study on satellite data assimilation for WRF model. AIRS/CRIS sounder profile data are used to assimilate the initial condition for the customized regional WRF model (GINA-WRF model). Normalized standard deviation, RMSE, and correlation statistic analysis methods are applied to analyze one case of 48 hours forecasts and one month of 24-hour forecasts in order to evaluate the improvement of regional numerical model from Data assimilation. The final goal of the research is to provide improved real-time short-time forecast for Alaska regions.

  3. Emulator-assisted data assimilation in complex models

    Science.gov (United States)

    Margvelashvili, Nugzar Yu; Herzfeld, Mike; Rizwi, Farhan; Mongin, Mathieu; Baird, Mark E.; Jones, Emlyn; Schaffelke, Britta; King, Edward; Schroeder, Thomas

    2016-09-01

    Emulators are surrogates of complex models that run orders of magnitude faster than the original model. The utility of emulators for the data assimilation into ocean models is still not well understood. High complexity of ocean models translates into high uncertainty of the corresponding emulators which may undermine the quality of the assimilation schemes based on such emulators. Numerical experiments with a chaotic Lorenz-95 model are conducted to illustrate this point and suggest a strategy to alleviate this problem through the localization of the emulation and data assimilation procedures. Insights gained through these experiments are used to design and implement data assimilation scenario for a 3D fine-resolution sediment transport model of the Great Barrier Reef (GBR), Australia.

  4. North American Land Data Assimilation System Phase 2

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — The goal of the North American Land Data Assimilation System (NLDAS) is to construct quality-controlled, and spatially and temporally consistent, land-surface model...

  5. Data Assimilation in Integrated and Distributed Hydrological Models

    DEFF Research Database (Denmark)

    Zhang, Donghua

    Integrated hydrological models are frequently used in water-related environmental resource management. With our better understanding of the hydrological processes and the improved computational power, hydrological models are becoming increasingly more complex as they integrate multiple hydrological...... to efficient use of traditional and new observational data in integrated hydrological models, as this technique can improve model prediction and reduce model uncertainty. The thesis investigates several challenges within the scope of data assimilation in integrated hydrological models. From the methodological...... assimilation. First, a systematic analysis was carried out for the case where groundwater hydraulic heads are assimilated in an integrated hydrological model. A data assimilation framework was developed and tested on synthetic data, and proved to be robust. It improved state estimation and was able to handle...

  6. Data assimilation: Particle filter and artificial neural networks

    International Nuclear Information System (INIS)

    The goal of this work is to present the performance of the Neural Network Multilayer Perceptrons trained to emulate a Particle Filter in the context of data assimilation. Techniques for data assimilation are applied for the Lorenz system, which presents a strong nonlinearity and chaotic nature. The cross validation method was used for training the network. Good results were obtained applying the multilayer perceptrons neural network.

  7. Variational Data Assimilation for Optimizing Boundary Conditions in Ocean Models

    CERN Document Server

    Kazantsev, Christine; Tolstykh, Mikhail

    2016-01-01

    The review describes the development of ideas Gury Ivanovich Marchuk in the field of variational data assimilation for ocean models applied in particular in coupled models for long-range weather forecasts. Particular attention is paid to the optimization of boundary conditions on rigid boundaries. As idealized and realistic model configurations are considered. It is shown that the optimization allows us to determine the most sensitive model operators and bring the model solution closer to the assimilated data.

  8. Von Bezold assimilation effect reverses in stereoscopic conditions

    OpenAIRE

    Soranzo, Alessandro; Galmonte, Alessandro; Agostini, Tiziano

    2010-01-01

    Lightness contrast and lightness assimilation are opposite phenomena: in contrast, grey targets appear darker when bordering bright surfaces (inducers) rather than dark ones; in assimilation, the opposite occurs. The question is: which visual process favours the occurrence of one phenomenon over the other? Researchers provided three answers to this question. The first asserts that both phenomena are caused by peripheral processes; the second attributes their occurrence to centr...

  9. Sensitivity tests for an ensemble Kalman filter for aerosol assimilation

    OpenAIRE

    N. A. J. Schutgens; T. Miyoshi; Takemura, T.; Nakajima, T

    2010-01-01

    We present sensitivity tests for a global aerosol assimilation system utilizing AERONET observations of AOT (aerosol optical thickness) and AAE (aerosol Ångström exponent). The assimilation system employs an ensemble Kalman filter which requires optimization of three numerical parameters: ensemble size nens, local patch size npatch and inflation factor ρ. In addition, experiments are performed to test ...

  10. Economic assimilation of immigrants : a comparison between Norway and Canada

    OpenAIRE

    2007-01-01

    The economic assimilation of immigrants in Norway is analyzed in this thesis. Since Norway and Canada have different immigration policies, the economic assimilations of immigrants in these two countries are compared. Unlike Norway, Canada uses a “point system” to target economic and demographic growth which results in a large class of economic immigrants. The entry effect, the years effect, the cohort effect and the period effect, as defined in previous academic literature, are considered....

  11. Absorptive Capacity and Contextual Factors that Influence Green IT Assimilation

    OpenAIRE

    Vanessa A Cooper; Alemayehu Molla

    2014-01-01

    The first wave of research in Green IT has often focused on organisational adoption. As Green IT matures in organisations it is important to look beyond adoption and to investigate the assimilation of Green IT. To this end we draw from and compare two theories – contextual theory and absorptive capacity – and investigate which of the two theories better explains the level of Green IT assimilation in organisations. Results from an international survey of 148 large organisations show that both ...

  12. Socioeconomic assimilation and wealth accumulation of migrants in Australia

    OpenAIRE

    Vaira-Lucero, Matias; Nahm, Daehoon; Tani, Massimiliano

    2012-01-01

    This paper investigates to what extent the wealth accumulation of immigrants is explained by their degree of assimilation, defined as the immigrants' capacity to become more similar over time to the local people in terms of their norms, values, behaviours, and socioeconomic characteristics. The existing practice to measure assimilation is the use of a time-dimensioned variable like years since migration, which reflects the individual's adaptation to the host country through the implied acquis...

  13. Enhanced ensemble-based 4DVar scheme for data assimilation

    OpenAIRE

    Yang, Yin; Robinson, Cordelia; Heitz, Dominique; Mémin, Etienne

    2015-01-01

    International audience Ensemble based optimal control schemes combine the components of ensemble Kalman filters and variational data assimilation (4DVar). They are trendy because they are easier to implement than 4DVar. In this paper, we evaluate a modified version of an ensemble based optimal control strategy for image data assimilation. This modified method is assessed with a Shallow Water model combined with synthetic data and original incomplete experimental depth sensor observations. ...

  14. Autoregressive Models of Background Errors for Chemical Data Assimilation

    OpenAIRE

    Constantinescu, Emil M.; Chai, Tianfeng; Sandu, Adrian; Gregory R. Carmichael

    2006-01-01

    The task of providing an optimal analysis of the state of the atmosphere requires the development of dynamic data-driven systems that efficiently integrate the observational data and the models. Data assimilation (DA) is the process of adjusting the states or parameters of a model in such a way that its outcome (prediction) is close, in some distance metric, to observed (real) states. It is widely accepted that a key ingredient of successful data assimilation is a realistic estimation of th...

  15. Endogenous assimilation and immigrant adjustment in longitudinal data

    OpenAIRE

    Beenstock, Michael; Chiswick, Barry R; Paltiel, Ari

    2005-01-01

    We create a longitudinal data set by matching immigrants in Israel's censuses for 1983 and 1995. These panel data reject the Immigrant Assimilation Hypothesis (IAH), which predicts that immigrants with shorter durations in 1983 should have experienced faster earnings growth between 1983 and 1995. By contrast, IAH is corroborated by the synthetic cohort methodology (SCM) over the same period. We suggest that SCM is subject to survivor bias, which increases the apparent degree of assimilation. ...

  16. Labor Market Assimilation of Recent Immigrants in Spain

    OpenAIRE

    Amuedo-Dorantes, Catalina; de la Rica, Sara

    2006-01-01

    This paper provides a preliminary analysis of the employment and occupational assimilation of recent immigrant waves to the Spanish labor market as their residencies lengthen. Using Spanish data from the 2001 Population Census and the 2002 Earnings Structure Survey, we find evidence of immigrant employment and occupational assimilation significantly varying by gender, origin and educational attainment. For instance, EU15 immigrants do not display an employment or occupational gap with respect...

  17. Immigrant quality and assimilation: A review of the US literature

    OpenAIRE

    T. Paul Schultz

    1998-01-01

    Empirical research on US immigrants is reviewed: their productivity and assimilation; their contribution and use of public services; and their impact on native Americans. I discuss the characteristics of cohorts of immigrants that enter the United States at different times, and then quantify the assimilation of immigrants, typically in terms of economic productivity of immigrants compared with natives. Few have found quantifiable negative effects of immigrants on native wages or unemployment ...

  18. Does better pre-migration performance accelerate immigrants' wage assimilation?

    OpenAIRE

    Hirsch, Boris; Jahn, Elke J.; Toomet, Ott; Hochfellner, Daniela

    2013-01-01

    This paper analyzes wage assimilation of ethnic German immigrants to Germany. We use unique administrative data that include a standardized measure of immigrants' pre-migration wage based on occupation, industry, tenure, qualification, and the German wage structure. We find that immigrants experience a substantial initial wage disadvantage compared to natives. During their first 15 years in the host country they manage to close a considerable part of this gap, though assimilation is only part...

  19. Immigrants'assimilation process in a segmented labor market

    OpenAIRE

    Rodríguez Planas, Núria; Alcobendas, Miguel Angel

    2010-01-01

    While much of the literature on immigrants' assimilation has focused on countries with a large tradition of receiving immigrants and with flexible labor markets, very little is known on how immigrants adjust to other types of host economies. With its severe dual labor market, and an unprecedented immigration boom, Spain presents a quite unique experience to analyze immigrations' assimilation process. Using data from the 2000 to 2008 Labor Force Survey, we find that immigrants are more occupat...

  20. How do immigrants spend their time? The process of assimilation

    OpenAIRE

    Hamermesh, Daniel S; Trejo, Stephen J.

    2010-01-01

    Using 2004-2008 data from the American Time Use Survey, we show that sharp differences between the time use of immigrants and natives become noticeable when activities are distinguished by incidence and intensity. We develop a theory of the process of assimilation – what immigrants do with their time – based on the notion that assimilating activities entail fixed costs. The theory predicts that immigrants will be less likely than natives to undertake such activities, but conditional on undert...

  1. Immigrants' Assimilation Process In A Segmented Labor Market

    OpenAIRE

    Miguel Ángel Alcobendas; Núria Rodríquez-Planas

    2010-01-01

    While much of the literature on immigrants' assimilation has focused on countries with a large tradition of receiving immigrants and with flexible labor markets, very little is known on how immigrants adjust to other types of host economies. With its severe dual labor market, and an unprecedented immigration boom, Spain presents a quite unique experience to analyze immigrations' assimilation process. Using data from the 2000 to 2008 Labor Force Survey, we find that immigrants are more occupat...

  2. Assimilative learning with the aid of cognitive maps

    OpenAIRE

    D. Läge; Oberholzer, R; Egli, S.; R. Streule

    2008-01-01

    Assimilative learning is understood as integrating new information into existing knowledge or cognitive structures without restructuring the current schema. If new information causes inconsistencies, cognitive efforts are necessary to reorganize or to accommodate the old knowledge. Thus, assimilative learning is more efficient and economic. Nonetheless a stable and most notably a correct memory representation which “spans” the knowledge space is essential. The current article highlights the l...

  3. Assimilating compact phase space retrievals of atmospheric composition with WRF-Chem/DART: a regional chemical transport/ensemble Kalman filter data assimilation system

    Science.gov (United States)

    Mizzi, Arthur P.; Arellano, Avelino F., Jr.; Edwards, David P.; Anderson, Jeffrey L.; Pfister, Gabriele G.

    2016-03-01

    This paper introduces the Weather Research and Forecasting Model with chemistry/Data Assimilation Research Testbed (WRF-Chem/DART) chemical transport forecasting/data assimilation system together with the assimilation of compact phase space retrievals of satellite-derived atmospheric composition products. WRF-Chem is a state-of-the-art chemical transport model. DART is a flexible software environment for researching ensemble data assimilation with different assimilation and forecast model options. DART's primary assimilation tool is the ensemble adjustment Kalman filter. WRF-Chem/DART is applied to the assimilation of Terra/Measurement of Pollution in the Troposphere (MOPITT) carbon monoxide (CO) trace gas retrieval profiles. Those CO observations are first assimilated as quasi-optimal retrievals (QORs). Our results show that assimilation of the CO retrievals (i) reduced WRF-Chem's CO bias in retrieval and state space, and (ii) improved the CO forecast skill by reducing the Root Mean Square Error (RMSE) and increasing the Coefficient of Determination (R2). Those CO forecast improvements were significant at the 95 % level. Trace gas retrieval data sets contain (i) large amounts of data with limited information content per observation, (ii) error covariance cross-correlations, and (iii) contributions from the retrieval prior profile that should be removed before assimilation. Those characteristics present challenges to the assimilation of retrievals. This paper addresses those challenges by introducing the assimilation of compact phase space retrievals (CPSRs). CPSRs are obtained by preprocessing retrieval data sets with an algorithm that (i) compresses the retrieval data, (ii) diagonalizes the error covariance, and (iii) removes the retrieval prior profile contribution. Most modern ensemble assimilation algorithms can efficiently assimilate CPSRs. Our results show that assimilation of MOPITT CO CPSRs reduced the number of observations (and assimilation computation

  4. Recent Advances in the GRACE Data Assimilation System (Invited)

    Science.gov (United States)

    Zaitchik, B. F.; Rodell, M.; Kumar, S.; Reichle, R. H.; Bolten, J. D.; Bergaoui, K.

    2013-12-01

    Anomalies in Terrestrial Water Storage (TWS) derived from the Gravity Recovery and Climate Experiment (GRACE) mission have been used effectively to study hydrologic variability and trends at basin scale across diverse climatic and geologic conditions. Many hydrology and water resources applications, however, require water storage estimates at higher spatial resolution, greater temporal frequency, and with greater physical specificity (e.g., groundwater versus soil moisture versus snow) than GRACE alone can offer. The GRACE Data Assimilation System (GRACE-DAS) was developed to merge GRACE information on large-scale TWS anomalies with physically-based advanced Land Surface Models in order to improve model simulation of water storage while disaggregating and downscaling the raw GRACE TWS estimate. The primary assimilation algorithm is a variant of the ensemble Kalman Smoother. In recent years the system has been applied to studies of water resources and drought monitoring over four different continents. These experiences have led to refinements in the assimilation system that include modifications to land surface model parameters and the treatment of irrigation withdrawals, adjustments in the assimilation algorithm for snow updates, and, most recently, the implementation of a gridded observation assimilation capability that allows for a more flexible application of the system. This presentation will provide an overview of current GRACE-DAS capabilities, report on recent innovations in the modeling system, and describe future directions in GRACE data assimilation research and applications.

  5. Cholesterol assimilation by Lactobacillus probiotic bacteria: an in vitro investigation.

    Science.gov (United States)

    Tomaro-Duchesneau, Catherine; Jones, Mitchell L; Shah, Divya; Jain, Poonam; Saha, Shyamali; Prakash, Satya

    2014-01-01

    Excess cholesterol is associated with cardiovascular diseases (CVD), an important cause of mortality worldwide. Current CVD therapeutic measures, lifestyle and dietary interventions, and pharmaceutical agents for regulating cholesterol levels are inadequate. Probiotic bacteria have demonstrated potential to lower cholesterol levels by different mechanisms, including bile salt hydrolase activity, production of compounds that inhibit enzymes such as 3-hydroxy-3-methylglutaryl coenzyme A, and cholesterol assimilation. This work investigates 11 Lactobacillus strains for cholesterol assimilation. Probiotic strains for investigation were selected from the literature: Lactobacillus reuteri NCIMB 11951, L. reuteri NCIMB 701359, L. reuteri NCIMB 702655, L. reuteri NCIMB 701089, L. reuteri NCIMB 702656, Lactobacillus fermentum NCIMB 5221, L. fermentum NCIMB 8829, L. fermentum NCIMB 2797, Lactobacillus rhamnosus ATCC 53103 GG, Lactobacillus acidophilus ATCC 314, and Lactobacillus plantarum ATCC 14917. Cholesterol assimilation was investigated in culture media and under simulated intestinal conditions. The best cholesterol assimilator was L. plantarum ATCC 14917 (15.18±0.55 mg/10(10) cfu) in MRS broth. L. reuteri NCIMB 701089 assimilated over 67% (2254.70±63.33 mg/10(10) cfu) of cholesterol, the most of all the strains, under intestinal conditions. This work demonstrates that probiotic bacteria can assimilate cholesterol under intestinal conditions, with L. reuteri NCIMB 701089 showing great potential as a CVD therapeutic. PMID:25295259

  6. Cholesterol Assimilation by Lactobacillus Probiotic Bacteria: An In Vitro Investigation

    Directory of Open Access Journals (Sweden)

    Catherine Tomaro-Duchesneau

    2014-01-01

    Full Text Available Excess cholesterol is associated with cardiovascular diseases (CVD, an important cause of mortality worldwide. Current CVD therapeutic measures, lifestyle and dietary interventions, and pharmaceutical agents for regulating cholesterol levels are inadequate. Probiotic bacteria have demonstrated potential to lower cholesterol levels by different mechanisms, including bile salt hydrolase activity, production of compounds that inhibit enzymes such as 3-hydroxy-3-methylglutaryl coenzyme A, and cholesterol assimilation. This work investigates 11 Lactobacillus strains for cholesterol assimilation. Probiotic strains for investigation were selected from the literature: Lactobacillus reuteri NCIMB 11951, L. reuteri NCIMB 701359, L. reuteri NCIMB 702655, L. reuteri NCIMB 701089, L. reuteri NCIMB 702656, Lactobacillus fermentum NCIMB 5221, L. fermentum NCIMB 8829, L. fermentum NCIMB 2797, Lactobacillus rhamnosus ATCC 53103 GG, Lactobacillus acidophilus ATCC 314, and Lactobacillus plantarum ATCC 14917. Cholesterol assimilation was investigated in culture media and under simulated intestinal conditions. The best cholesterol assimilator was L. plantarum ATCC 14917 (15.18 ± 0.55 mg/1010 cfu in MRS broth. L. reuteri NCIMB 701089 assimilated over 67% (2254.70 ± 63.33 mg/1010 cfu of cholesterol, the most of all the strains, under intestinal conditions. This work demonstrates that probiotic bacteria can assimilate cholesterol under intestinal conditions, with L. reuteri NCIMB 701089 showing great potential as a CVD therapeutic.

  7. A diagnostic statistical cloud scheme for data assimilation purposes

    Science.gov (United States)

    Tompkins, A. M.; Janiskova, M.

    2003-04-01

    The task of assimilating cloud and rainfall information is steadily increasing in importance with a new generation of observing platforms. The inherent non-linearity of many cloud related processes exacerbates the archetypical assimilation dilemma. Overly simplistic schemes may not represent the physical cloud processes adequately for assimilation purposes. At the other extreme, many current cloud schemes used in forecast or climate models are simply too complex for the tangent linear and adjoint codes to be constructed. Even if the latter is achievable, the full schemes in forecast models often contain discrete switches and non linear processes to maximize forecast performance, but render the linear approximation invalid for perturbations of the magnitude of typical analysis increments. This may cause convergence problems over typical assimilation windows (currently 12 hours) in 4D variational assimilation (4DVAR). The existing ECMWF cloud scheme used in the assimilating model is deficient since there is no connection between diagnosed cloud cover, water/ice and precipitation generation. We thus present a new non-linear diagnostic cloud scheme for which the tangent linear and adjoint codes have been constructed. The scheme is based on prognostic humidity and temperature variables and a diagnostic assumption concerning subgrid variability is used to derive cloud water, ice and cover characteristics. Results using the new scheme are shown.

  8. Assimilation of IRS-P4 (MSMR) meteorological data in the NCMRWF global data assimilation system

    Indian Academy of Sciences (India)

    Rupa Kamineni; S R H Rizvi; S C Kar; U C Mohanty; R K Paliwal

    2002-09-01

    Oceansat-1 was successfully launched by India in 1999, with two payloads, namely Multi-frequency Scanning Microwave Radiometer (MSMR) and Ocean Color Monitor (OCM) to study the biological and physical parameters of the ocean. The MSMR sensor is configured as an eight-channel radiometer using four frequencies with dual polarization. The MSMR data at 75km resolution from the Oceansat-I have been assimilated in the National Centre for Medium Range Weather Forecasting (NCMRWF) data assimilation forecast system. The operational analysis and forecast system at NCMRWF is based on a T80L18 global spectral model and Spectral Statistical Inter-polation (SSI) scheme for data analysis. The impact of the MSMR data is seen globally, however it is significant over the oceanic region where conventional data are rare. The dry-nature of the control analyses have been removed by utilizing the MSMR data. Therefore, the total precipitable water data from MSMR has been identified as a very crucial parameter in this study. The impact of surface wind speed from MSMR is to increase easterlies over the tropical Indian Ocean. Shifting of the positions of westerly troughs and ridges in the south Indian Ocean has contributed to reduction of temperature to around 30°S.

  9. A hybrid variational ensemble data assimilation for the HIgh Resolution Limited Area Model (HIRLAM)

    OpenAIRE

    N. Gustafsson; J. Bojarova; O. Vignes

    2014-01-01

    A hybrid variational ensemble data assimilation has been developed on top of the HIRLAM variational data assimilation. It provides the possibility of applying a flow-dependent background error covariance model during the data assimilation at the same time as full rank characteristics of the variational data assimilation are preserved. The hybrid formulation is based on an augmentation of the assimilation control variable with localised weights to be assigned to a set of ense...

  10. 15 Years of Wave Height Data Assimilation

    Science.gov (United States)

    Janssen, P.

    2006-07-01

    Over the past fiffteen years there has been a continuous interplay between ocean wave forecasting and altimeter data resulting in improvemen ts in both. The prospect of global observations of wind and waves gave a significan t stimulus to wave model development, while the need to have reliab le wav e predictions stimu lated the d evelopment of altimeter wind and wave products. This p aper covers the following: - Altimeter W ave Height D ata Assimilation of altimeter wave height data is of vital importance for the quality of the wave analysis and ocean wave forecasting. In addition, these data are a great h elp in diagnosing wave model problems. Furthermore th ey have great value in ob taining a g lobal wave climato logy. -Altimeter W ind Sp eed D ata Wind speed data are important for mon itor ing the quality of modelled surface w ind. Recen tly, the 'classical' W itter and Ch elton (1991) retriev al algorithm for wind speed (σ0 = ƒ(U10))has been extended by includ ing sea state eff ects and has been in troduced for Jason. On the other hand, th e classical scheme was improved by Abdalla (2006) and introduced for ENVISAT. Th e Abdalla algorithm is shown to perform better, however . Altimeter w indspeed data h ave the potential to be of great value in hurricane conditions as w ell. -Tsunamis An altimeter can ind eed observe tsunami even ts, but there is doubt th at this may be of value for an early warning system.

  11. 基于灰色局势决策的备件品种级别配置%Application of Grey Situation Decision Approach to Determining the Assortment of Spares and Level of Repair

    Institute of Scientific and Technical Information of China (English)

    李云锋; 王瑞林; 贾云非; 长建宇

    2011-01-01

    Analyzes the significant factors which have influence on spares assortment. This paper introduce a new method of quantizing spares assortment that is grey situation decision approach. It accounts for spares assortment basis on level of repair.%分析了影响备件品种确定的主要因素,引入灰色局势决策法,解决了按维修级别进行备件品种确定的问题,提供一种新的备件品种量化方法.

  12. Application Effect Analyses of Computer Cotton Assorting System%计算机配棉系统的应用效果分析

    Institute of Scientific and Technical Information of China (English)

    丁忠平; 袁安民

    2011-01-01

    Cotton assorting and prediction yarn quality effect by computer cotton assorting system was analyzed. Functions of computer cotton assorting system were introduced. Micronaire value and fiber length were selected as the first case,micronaire value,fiber length and fiber uniform were selected as the second case,cotton assorting and spinning test were done in the two cases. The result shows that the error between prediction data of the first case and practical data are larger. While the error between prediction data of the second case and practical data are less, the yam quality can fit use demands. It is considered that better yarn quality prediction result can be got when cotton bales classification of computer cotton assorting system can be set rationally according to raw material. Prediction result of computer cotton assorting system can be more accurate when equipment, processing etc are considered comprehensively.%分析计算机配棉系统配棉及预测成纱质量的效果.介绍了计算机配棉系统的功能,分别选取马克隆值和长度(方案1)及马克隆值、长度和纤维整齐度(方案2)为参数进行配棉及纺纱试验.试验结果表明:方案1的预测理论数据与实际生产数据误差较大,而方案2的误差明显减小,生产出的成纱质量符合使用要求.认为:根据原料情况合理设置计算机配棉系统的棉包分类分组方能取得理想的成纱质量预测结果,如能综合考虑设备、工艺等因素,计算机配棉系统的预测结果会更加精确.

  13. Assimilation of GPM GMI Rainfall Product with WRF GSI

    Science.gov (United States)

    Li, Xuanli; Mecikalski, John; Zavodsky, Bradley

    2015-01-01

    The Global Precipitation Measurement (GPM) is an international mission to provide next-generation observations of rain and snow worldwide. The GPM built on Tropical Rainfall Measuring Mission (TRMM) legacy, while the core observatory will extend the observations to higher latitudes. The GPM observations can help advance our understanding of precipitation microphysics and storm structures. Launched on February 27th, 2014, the GPM core observatory is carrying advanced instruments that can be used to quantify when, where, and how much it rains or snows around the world. Therefore, the use of GPM data in numerical modeling work is a new area and will have a broad impact in both research and operational communities. The goal of this research is to examine the methodology of assimilation of the GPM retrieved products. The data assimilation system used in this study is the community Gridpoint Statistical Interpolation (GSI) system for the Weather Research and Forecasting (WRF) model developed by the Development Testbed Center (DTC). The community GSI system runs in independently environment, yet works functionally equivalent to operational centers. With collaboration with the NASA Short-term Prediction Research and Transition (SPoRT) Center, this research explores regional assimilation of the GPM products with case studies. Our presentation will highlight our recent effort on the assimilation of the GPM product 2AGPROFGMI, the retrieved Microwave Imager (GMI) rainfall rate data for initializing a real convective storm. WRF model simulations and storm scale data assimilation experiments will be examined, emphasizing both model initialization and short-term forecast of precipitation fields and processes. In addition, discussion will be provided on the development of enhanced assimilation procedures in the GSI system with respect to other GPM products. Further details of the methodology of data assimilation, preliminary result and test on the impact of GPM data and the

  14. Development of an EUV data assimilation technique for plasmasphere modeling

    International Nuclear Information System (INIS)

    Complete text of publication follows. The structure of the plasmasphere is strongly controlled by the electric field imposed on the magnetosphere. In order to model the dynamics of the plasmasphere, it is important to know the spatial structure of the electric potential in the inner magnetosphere. However, since it is difficult to know the global electric potential distribution in the magnetosphere due to the lack of observation, it is difficult to grasp the dynamics of the plasmasphere using in-situ measurements. Recently we have developed a data assimilation technique which incorporates a remote observation of energetic neutral atoms (ENAs) from the IMAGE satellite into a ring current model. This ENA data assimilation technique provides estimates of the distributions of the ring current ions and electric potential in the inner magnetosphere. The present study is conducted aiming at applying a similar approach for modeling the plasmasphere. We are now engaged in the development of a data assimilation technique for providing estimates of the spatial structures of the plasmasphere and electric potential. The estimation is performed by incorporating remote imaging data of extreme ultra-violet (EUV) from the IMAGE satellite into a simulation model of the plasmasphere. We assume the magnetospheric electric potential distribution to be unknown, and estimate it in the course of the assimilation process. The plasmaspheric ion distribution is estimated according to the estimated electric potential and the plasmasphere simulation model. At present, we are conducting data assimilation experiments using artificial EUV data sets to evaluate the EUV data assimilation approach. The experimental result suggests that the data assimilation of the EUV imaging data provides useful information for understanding the temporal and spatial variations of the plasmasphere.

  15. Impacts of data assimilation on the global ocean carbonate system

    Science.gov (United States)

    Visinelli, L.; Masina, S.; Vichi, M.; Storto, A.; Lovato, T.

    2016-06-01

    In an ocean reanalysis, historical observations are combined with ocean and biogeochemical general circulation models to produce a reconstruction of the oceanic properties in past decades. This is one possible method to better constrain the role of the ocean carbon cycle in the determination of the air-sea CO2 flux. In this work, we investigate how the assimilation of physical variables and subsequently the combined assimilation of physical data and inorganic carbon variables - namely dissolved inorganic carbon (DIC) and alkalinity - affect the modelling of the marine carbonate system and the related air-sea CO2 fluxes. The performance of the two assimilation exercises are quantitatively assessed against the assimilated DIC and alkalinity data and the independent ocean surface pCO2 observations from global datasets. We obtain that the assimilation of physical observations has contrasting effects in different ocean basins when compared with the DIC and alkalinity data: it reduces the root-mean square error against the observed pCO2 in the Atlantic and Southern oceans, while increases the model error in the North Pacific and Indian Oceans. In both cases the corrected evaporation rates are the major factor determining the changes in concentrations. The assimilation of inorganic carbon variables on top of the physical data gives a generalized improvement in the model error of inorganic carbon variables, also improving the annual mean and spatial distribution of air-sea fluxes in agreement with other published estimates. These results indicate that data assimilation of physical and inorganic carbon data does not guarantee the improvement of the simulated pCO2 in all the oceanic regions; nevertheless, errors in pCO2 are reduced by a factor corresponding to those associated with the air-sea flux formulations.

  16. A new assimilation method with physical mechanism to estimate evapotranspiration

    Science.gov (United States)

    Ye, Wen; Xu, Xinyi

    2016-04-01

    The accurate estimation of regional evapotranspiration has been a research hotspot in the field of hydrology and water resources both in domestic and abroad. A new assimilation method with physical mechanism was proposed to estimate evapotranspiration, which was easier to apply. Based on the evapotranspiration (ET) calculating method with soil moisture recurrence relations in the Distributed Time Variant Gain Model (DTVGM) and Ensemble Kalman Filter (EnKF), it constructed an assimilation system for recursive calculation of evapotranspiration in combination with "observation value" by the retrieval data of evapotranspiration through the Two-Layer Remote Sensing Model. By updating the filter in the model with assimilated evapotranspiration, synchronization correction to the model estimation was achieved and more accurate time continuous series values of evapotranspiration were obtained. Through the verification of observations in Xiaotangshan Observatory and hydrological stations in the basin, the correlation coefficient of remote sensing inversion evapotranspiration and actual evapotranspiration reaches as high as 0.97, and the NS efficiency coefficient of DTVGM model was 0.80. By using the typical daily evapotranspiration from Remote Sensing and the data from DTVGM Model, we assimilated the hydrological simulation processes with DTVGM Model in Shahe Basin in Beijing to obtain continuous evapotranspiration time series. The results showed that the average relative error between the remote sensing values and DTVGM simulations is about 12.3%, and for the value between remote sensing retrieval data and assimilation values is 4.5%, which proved that the assimilation results of Ensemble Kalman Filter (EnKF) were closer to the "real" data, and was better than the evapotranspiration simulated by DTVGM without any improvement. Keyword Evapotranspiration assimilation Ensemble Kalman Filter Distributed hydrological model Two-Layer Remote Sensing Model

  17. Meteorological Data Assimilation by Adaptive Bayesian Optimization.

    Science.gov (United States)

    Purser, Robert James

    1992-01-01

    The principal aim of this research is the elucidation of the Bayesian statistical principles that underlie the theory of objective meteorological analysis. In particular, emphasis is given to aspects of data assimilation that can benefit from an iterative numerical strategy. Two such aspects that are given special consideration are statistical validation of the covariance profiles and nonlinear initialization. A new economic algorithm is presented, based on the imposition of a sparse matrix structure for all covariances and precisions held during the computations. It is shown that very large datasets may be accommodated using this structure and a good linear approximation to the analysis equations established without the need to unnaturally fragment the problem. Since the integrity of the system of analysis equations is preserved, it is a relatively straight-forward matter to extend the basic analysis algorithm to one that incorporates a check on the plausibility of the statistical model assumed for background errors--the so-called "validation" problem. Two methods of validation are described within the sparse matrix framework: the first is essentially a direct extension of the Bayesian principles to embrace, not only the regular analysis variables, but also the parameters that determine the precise form of the covariance functions; the second technique is the non-Bayesian method of generalized cross validation adapted for use within the sparse matrix framework. The later part of this study is concerned with the establishment of a consistent dynamical balance within a forecast model--the initialization problem. The formal principles of the modern theory of initialization are reviewed and a critical examination is made of the concept of the "slow manifold". It is demonstrated, in accordance with more complete nonlinear models, that even within a simple three-mode linearized system, the notion that a universal slow manifold exists is untenable. It is therefore argued

  18. Evidence indicating independent assortment of framework and complementarity-determining segments of the variable regions of rabbit light chains. Delineation of a possible J minigene.

    Science.gov (United States)

    Kabat, E A; Wu, T T; Bilofsky, H

    1980-07-01

    Amino acid sequences of rabbit light chains show considerable evidence of independent assortment of framework (FR) and complementarity-determining (CDR) segments. This suggests that they are coded for by independent genetic units (minigaenes) and that individual light chains are assembled somatically by recombining these units. Identical FR sets with multiple members generally comprise chains with different specificities, whereas identical CDR sets tend to have chains of a single specificity. A J segment, which, by analogy with mouse light chains, is made up of the last two residues of CDR3 plus all of FR4, contained 18 different sets and could contribute to diversity generated by CDR3. The longest segment, FR3, had a very large number of sets. Evidence is presented showing that the number of sets could be substantially reduced by permitting FR3 to be formed by two independently assorting segments comprising residues 57-68 and 69-88.

  19. Assimilation of Altimeter Data into a Quasigeostrophic Model of the Gulf Stream System. Part 2; Assimilation Results

    Science.gov (United States)

    Capotondi, Antonietta; Holland, William R.; Malanotte-Rizzoli, Paola

    1995-01-01

    The improvement in the climatological behavior of a numerical model as a consequence of the assimilation of surface data is investigated. The model used for this study is a quasigeostrophic (QG) model of the Gulf Stream region. The data that have been assimilated are maps of sea surface height that have been obtained as the superposition of sea surface height variability deduced from the Geosat altimeter measurements and a mean field constructed from historical hydrographic data. The method used for assimilating the data is the nudging technique. Nudging has been implemented in such a way as to achieve a high degree of convergence of the surface model fields toward the observations. Comparisons of the assimilation results with available in situ observations show a significant improvement in the degree of realism of the climatological model behavior, with respect to the model in which no data are assimilated. The remaining discrepancies in the model mean circulation seem to be mainly associated with deficiencies in the mean component of the surface data that are assimilated. On the other hand, the possibility of building into the model more realistic eddy characteristics through the assimilation of the surface eddy field proves very successful in driving components of the mean model circulation that are in relatively good agreement with the available observations. Comparisons with current meter time series during a time period partially overlapping the Geosat mission show that the model is able to 'correctly' extrapolate the instantaneous surface eddy signals to depths of approximately 1500 m. The correlation coefficient between current meter and model time series varies from values close to 0.7 in the top 1500 m to values as low as 0.1-0.2 in the deep ocean.

  20. Data Assimilation in Hydrodynamic Models of Continental Shelf Seas

    DEFF Research Database (Denmark)

    Sørensen, Jacob Viborg Tornfeldt

    2004-01-01

    This thesis consists of seven research papers published or submitted for publication in the period 2002-2004 together with a summary report. The thesis mainly deals with data assimilation of tide gauge data in two- and three-dimensional hydrodynamic models of the continental shelf seas. Assimilat......This thesis consists of seven research papers published or submitted for publication in the period 2002-2004 together with a summary report. The thesis mainly deals with data assimilation of tide gauge data in two- and three-dimensional hydrodynamic models of the continental shelf seas....... Assimilation of sea surface temperature and parameter estimation in hydrodynamic models are also considered. The main focus has been on the development of robust and efficient techniques applicable in real operational settings. The applied assimilation techniques all use a Kalman filter approach. They consist...... robust state estimate. The assimilation schemes used in this work are primarily based on two ensemble based schemes, the Ensemble Kalman Filter and the Reduced Rank Square Root Kalman Filter. In order to investigate the applicability of these and derived schemes, the sensitivity to filter parameters...

  1. Kinetics of 15NH4+ assimilation in Zea mays

    International Nuclear Information System (INIS)

    Comparative studies of 15NH4+ assimilation were undertaken with a GDH1-null mutant of Zea mays and a related (but not strictly isogenic) GDH1-positive wild type from which this mutant was derived. The kinetics of 15NH4+ assimilation into free amino acids and total reduced nitrogen were monitored in both roots and shoots of 2-week-old seedlings supplied with 5 millimolar 99% (15NH4)2SO4 via the aerated root medium in hydroponic culture over a 24-h period. The GDH1-null mutant, with a 10- to 15-fold lower total root GDH activity in comparison to the wild type, was found to exhibit a 40 to 50% lower rate of 15NH4+ assimilation into total reduced nitrogen. The lower rates of 15NH4+ assimilation in the mutant was associated with lower rates of labeling of several free amino acids (including glutamate, glutamine-amino N, aspartate, asparagine-amino N, and alanine) in both roots and shoots of the mutant in comparison to the wild type. Qualitatively, these labeling kinetics appear consistent with a reduced flux of 15N via glutamate in the GDH1-null mutant. However, the responses of the two genotypes to the potent inhibitor of glutamine synthetase, methionine sulfoximine, and differences in morphology of the two genotypes (particularly a lower shoot:root ratio in the GDH1-null mutant) urge caution in concluding that GDH1 is solely responsible for these differences in ammonia assimilation rate

  2. Assimilation impacts on Arctic Ocean circulation, heat and freshwater budgets

    Science.gov (United States)

    Zuo, Hao; Mugford, Ruth I.; Haines, Keith; Smith, Gregory C.

    We investigate the Arctic basin circulation, freshwater content (FWC) and heat budget by using a high-resolution global coupled ice-ocean model implemented with a state-of-the-art data assimilation scheme. We demonstrate that, despite a very sparse dataset, by assimilating hydrographic data in and near the Arctic basin, the initial warm bias and drift in the control run is successfully corrected, reproducing a much more realistic vertical and horizontal structure to the cyclonic boundary current carrying the Atlantic Water (AW) along the Siberian shelves in the reanalysis run. The Beaufort Gyre structure and FWC and variability are also more accurately reproduced. Small but important changes in the strait exchange flows are found which lead to more balanced budgets in the reanalysis run. Assimilation fluxes dominate the basin budgets over the first 10 years (P1: 1987-1996) of the reanalysis for both heat and FWC, after which the drifting Arctic upper water properties have been restored to realistic values. For the later period (P2: 1997-2004), the Arctic heat budget is almost balanced without assimilation contributions, while the freshwater budget shows reduced assimilation contributions compensating largely for surface salinity damping, which was extremely strong in this run. A downward trend in freshwater export at the Canadian Straits and Fram Strait is found in period P2, associated with Beaufort Gyre recharge. A detailed comparison with observations and previous model studies at the individual Arctic straits is also included.

  3. A novel data assimilation model for the plasmasphere

    Science.gov (United States)

    Nikoukar, R.; Bust, G. S.; Murr, D.

    2014-12-01

    We present a novel technique for imaging and data assimilation of the topside ionosphere and plasmasphere. The technique incorporates the SAMI2 model as a physics-based background model for assimilation. The Gauss-Markov Kalman filter technique is used to advance estimates of electron density and background error covariances forward in time. We incorporate regularization techniques in the assimilation algorithm to stabilize the solution in face of limited data perturbation to prevent non-physical altitudinal variation in density estimates due to limited availability of data. The above-the-horizon observations from the Global Positioning System (GPS) receiver onboard Constellation Observing System for Meteorology, Ionosphere and Climate (COSMIC) satellites are utilized in the assimilation algorithm. The estimation results show reasonable agreement with in-situ density measurements of Defense Meteorological Satellite Program satellites and Van Allen Probes derived densities during geomagnetically quiet and severe storm-time conditions, respectively. The results demonstrate great potential for the use of assimilation of COSMIC above-the-horizon measurements in monitoring and studying the morphology and dynamics of large-scale structures of the electron density in the topside ionosphere and plasmasphere.

  4. Architecting Service Based Sensor Networks for the Intelligent Assimilation

    Directory of Open Access Journals (Sweden)

    R. S. Ponmagal

    2014-01-01

    Full Text Available The aim of this paper is to propose an architectural model for assimilating distributed sensor networks through cloud paradigm. This strategy can be applied to monitor and control the physical parameters such as temperature, pressure, and level. It is proposed to consider the use of service oriented architecture to program and deploy the sensed parameters. The service oriented architecture for sensor network has been implemented in such a way that, for every specific requirement of the monitor center, the assimilation agent invokes the services of the sensors through a registry and the specific changes in the sensed parameters are also notified as auditable event using push interaction pattern of SOA. The assimilation agent serves as an intelligent component by providing authentication services. This SOA is extended to integrate different types of sensor networks through cloud environment. Hence several sensors can be networked together to monitor different process parameters and they have been assimilated with Internet by registering them as services, hence a complete distributed assimilation environment is exploited.

  5. Assimilation of GNSS radio occultation observations in GRAPES

    Science.gov (United States)

    Liu, Y.; Xue, J.

    2014-07-01

    This paper reviews the development of the global navigation satellite system (GNSS) radio occultation (RO) observations assimilation in the Global/Regional Assimilation and PrEdiction System (GRAPES) of China Meteorological Administration, including the choice of data to assimilate, the data quality control, the observation operator, the tuning of observation error, and the results of the observation impact experiments. The results indicate that RO data have a significantly positive effect on analysis and forecast at all ranges in GRAPES not only in the Southern Hemisphere where conventional observations are lacking but also in the Northern Hemisphere where data are rich. It is noted that a relatively simple assimilation and forecast system in which only the conventional and RO observation are assimilated still has analysis and forecast skill even after nine months integration, and the analysis difference between both hemispheres is gradually reduced with height when compared with NCEP (National Centers for Enviromental Prediction) analysis. Finally, as a result of the new onboard payload of the Chinese FengYun-3 (FY-3) satellites, the research status of the RO of FY-3 satellites is also presented.

  6. Assimilation of GNSS radio occultation observations in GRAPES

    Directory of Open Access Journals (Sweden)

    Y. Liu

    2014-07-01

    Full Text Available This paper reviews the development of the global navigation satellite system (GNSS radio occultation (RO observations assimilation in the Global/Regional Assimilation and PrEdiction System (GRAPES of China Meteorological Administration, including the choice of data to assimilate, the data quality control, the observation operator, the tuning of observation error, and the results of the observation impact experiments. The results indicate that RO data have a significantly positive effect on analysis and forecast at all ranges in GRAPES not only in the Southern Hemisphere where conventional observations are lacking but also in the Northern Hemisphere where data are rich. It is noted that a relatively simple assimilation and forecast system in which only the conventional and RO observation are assimilated still has analysis and forecast skill even after nine months integration, and the analysis difference between both hemispheres is gradually reduced with height when compared with NCEP (National Centers for Enviromental Prediction analysis. Finally, as a result of the new onboard payload of the Chinese FengYun-3 (FY-3 satellites, the research status of the RO of FY-3 satellites is also presented.

  7. An integrated GIS application system for soil moisture data assimilation

    Science.gov (United States)

    Wang, Di; Shen, Runping; Huang, Xiaolong; Shi, Chunxiang

    2014-11-01

    The gaps in knowledge and existing challenges in precisely describing the land surface process make it critical to represent the massive soil moisture data visually and mine the data for further research.This article introduces a comprehensive soil moisture assimilation data analysis system, which is instructed by tools of C#, IDL, ArcSDE, Visual Studio 2008 and SQL Server 2005. The system provides integrated service, management of efficient graphics visualization and analysis of land surface data assimilation. The system is not only able to improve the efficiency of data assimilation management, but also comprehensively integrate the data processing and analysis tools into GIS development environment. So analyzing the soil moisture assimilation data and accomplishing GIS spatial analysis can be realized in the same system. This system provides basic GIS map functions, massive data process and soil moisture products analysis etc. Besides,it takes full advantage of a spatial data engine called ArcSDE to effeciently manage, retrieve and store all kinds of data. In the system, characteristics of temporal and spatial pattern of soil moiture will be plotted. By analyzing the soil moisture impact factors, it is possible to acquire the correlation coefficients between soil moisture value and its every single impact factor. Daily and monthly comparative analysis of soil moisture products among observations, simulation results and assimilations can be made in this system to display the different trends of these products. Furthermore, soil moisture map production function is realized for business application.

  8. OpenDA-NEMO framework for ocean data assimilation

    Science.gov (United States)

    van Velzen, Nils; Altaf, Muhammad Umer; Verlaan, Martin

    2016-05-01

    Data assimilation methods provide a means to handle the modeling errors and uncertainties in sophisticated ocean models. In this study, we have created an OpenDA-NEMO framework unlocking the data assimilation tools available in OpenDA for use with NEMO models. This includes data assimilation methods, automatic parallelization, and a recently implemented automatic localization algorithm that removes spurious correlations in the model based on uncertainties in the computed Kalman gain matrix. We have set up a twin experiment where we assimilate sea surface height (SSH) satellite measurements. From the experiments, we can conclude that the OpenDA-NEMO framework performs as expected and that the automatic localization significantly improves the performance of the data assimilation algorithm by successfully removing spurious correlations. Based on these results, it looks promising to extend the framework with new kinds of observations and work on improving the computational speed of the automatic localization technique such that it becomes feasible to include large number of observations.

  9. Assimilating uncertain, dynamic and intermittent streamflow observations in hydrological models

    Science.gov (United States)

    Mazzoleni, Maurizio; Alfonso, Leonardo; Chacon-Hurtado, Juan; Solomatine, Dimitri

    2015-09-01

    Catastrophic floods cause significant socio-economical losses. Non-structural measures, such as real-time flood forecasting, can potentially reduce flood risk. To this end, data assimilation methods have been used to improve flood forecasts by integrating static ground observations, and in some cases also remote sensing observations, within water models. Current hydrologic and hydraulic research works consider assimilation of observations coming from traditional, static sensors. At the same time, low-cost, mobile sensors and mobile communication devices are becoming also increasingly available. The main goal and innovation of this study is to demonstrate the usefulness of assimilating uncertain streamflow observations that are dynamic in space and intermittent in time in the context of two different semi-distributed hydrological model structures. The developed method is applied to the Brue basin, where the dynamic observations are imitated by the synthetic observations of discharge. The results of this study show how model structures and sensors locations affect in different ways the assimilation of streamflow observations. In addition, it proves how assimilation of such uncertain observations from dynamic sensors can provide model improvements similar to those of streamflow observations coming from a non-optimal network of static physical sensors. This can be a potential application of recent efforts to build citizen observatories of water, which can make the citizens an active part in information capturing, evaluation and communication, helping simultaneously to improvement of model-based flood forecasting.

  10. Application of statistical emulation to an agent-based model: assortative mating and the reversal of gender inequality in education in Belgium.

    OpenAIRE

    De Mulder, Wim; Grow, André; Molenberghs, Geert; Verbeke, Geert

    2015-01-01

    We describe the application of statistical emulation to the outcomes of an agent-based model. The agent-based model simulates the mechanisms that might have linked the reversal of gender inequality in higher education with observed changes in educational assortative mating in Belgium. Using the statistical emulator as a computationally fast approximation to the expensive agent-based model, it is feasible to use a genetic algorithm in nding the parameter values for which the correspondin...

  11. Regulating effect of density and top-dressing time of nitrogen fertilizer on 14C-assimilation and distribution of assimilate of large-spike cultivar of wheat

    International Nuclear Information System (INIS)

    The results of present study indicated that laminas, especially first and second lamina from top, were the most important assimilating organs of large-spike cultivar of wheat at flag leaf stage. More than ninety percent of assimilate of a single stem was made by laminas, while the assimilate amount of sheathes only accounted for less than 10%. Not only assimilating rate but also transport and distribution efficiency was declined when the density was too high. Deferring top-dressing time of nitrogen fertilizer could increase both assimilate amount and transport and distribution efficiency

  12. Dissortative From the Outside, Assortative From the Inside: Social Structure and Behavior in the Industrial Trade Network

    CERN Document Server

    Kelman, Guy; Manes, Eran; Lamieri, Marco; Golo, Natasa; Solomon, Sorin

    2014-01-01

    It is generally accepted that neighboring nodes in financial networks are negatively assorted with respect to the correlation between their degrees. This feature would play an important 'damping' role in the market during downturns (periods of distress) since this connectivity pattern between firms lowers the chances of auto-amplifying (the propagation of) distress. In this paper we explore a trade-network of industrial firms where the nodes are suppliers or buyers, and the links are those invoices that the suppliers send out to their buyers and then go on to present to their bank for discounting. The network was collected by a large Italian bank in 2007, from their intermediation of the sales on credit made by their clients. The network also shows dissortative behavior as seen in other studies on financial networks. However, when looking at the credit rating of the firms, an important attribute internal to each node, we find that firms that trade with one another share overwhelming similarity. We know that m...

  13. I. V. Michurin’S Work on Expansion of the Plant Horticulture Assortment and Improvement of Food Quality

    Directory of Open Access Journals (Sweden)

    Sokolov Viktor V.

    2015-09-01

    Full Text Available October 2015 marks the 160th anniversary of the birth of Ivan V. Michurin. As a scientist and plant breeder, he made a significant improvement of many fruit and berry plants, and flowers. He developed methods of plant breeding, especially regarding long-distance hybridisation of fruit plants, and promoted gardening to the north and east of Russia. He introduced some new berry species, such as Actinidia and black chokeberry, and was the first in Russia to use dwarf and semi dwarf stocks of apples. Michurin initiated the mass movement of gardeners and horticulture experimenters in USSR who changed and significantly extended the assortment and areas of fruit and berries cultivation in the country. He not only brought together a representative collection of species and varieties of fruit, berry and flower plants from around the world, but also used them in breeding by hybridization, including interspecific. He created some new artificial interspecific hybrids such as Cerapadus (cherry and bird cherry tree hybrid, and others. Michurin created 132 cultivars. Eleven of them are not only cultivated, but are also included in “The State Register of Protected Plant Breeding of the Russian Federation”.

  14. Possible assortment of a1 and a2 region gene segments in human MHC class I molecules.

    Science.gov (United States)

    Johnson, G; Wu, T T

    1998-06-01

    Using pair-wise comparison of aligned nucleotide sequences of distinct and complete human MHC class I molecules, we have constructed triangular tables to study the similarities and differences of various a1 (exon 2) and a2 (exon 3) region sequences. There are two HLA-A (A*6901 and A*6601) and 13 HLA-B (B*4201, B*8101, B*4102, B*4801, B*4007, B*4001, B*4802, Dw53, B*4406, B*4402, B*3901, B*1514 and B*3702) sequences that have identical a1 sequences with other known MHC class I molecules, while their a2 sequences are the same as those of different ones. Of these 15, A*6901, B*4001 and B*4802 have previously been suggested as the results of recombination between A*6801 and A*0201, B*4101 and B*8101, and B*4801 and B*3501, respectively. However, many other sequences can also be used to generate them by recombination. Furthermore, their reciprocal products have never been identified. Thus, gene conversion has subsequently been suggested as an alternative. Another possible genetic mechanism for generating these nucleotide sequence similarities can be assortment, or that some gene segments can be duplicated or multiplicated to be used in different human MHC class I molecules. Interestingly, this genetic mechanism is probably absent for the generation of different mouse MHC class I molecules.

  15. HLA and epidermolysis bullosa: evidence for independent assortment of Weber-Cockayne subtype of epidermolysis bullosa and HLA complex.

    Science.gov (United States)

    Vaidya, S; Tyring, S K; Feldkamp, M; Johnson, L B; Fine, J D

    1991-05-01

    The purpose of this study was to examine the genetic linkage (but not the association) between HLA complex and Weber-Cockayne Subtype of epidermolysis bullosa (EBS-WC). We HLA typed 44 members of three multi-generation families in which 24 members have the clinical evidence of EBS-WC. The patterns of inheritance of various HLA haplotypes and the disease were mathematically analyzed to estimate frequency of recombination (i.e. genetic distance) between HLA complex and the disease by calculating Lod Scores for each family separately as well as all for three families combined. Our results show that only one family had a positive Lod Score. The Lod Scores for the remaining two families as well as the combined Lod Score for all three families were negative. These data suggest that odds are against the genetic linkage between HLA complex and Weber-Cockayne Subtype of epidermolysis bullosa and in favor of independent assortment of the disease and HLA complex.

  16. The Analysis Of The Strain Influence On Some Yield Elemnts On An Assortment Of Isogenic Wheat Varieties

    Science.gov (United States)

    Păniţă, Ovidiu

    2015-09-01

    In the years 2012-2014 on Banu-Maracine DRS were tested an assortment consists of 25 isogenic lines of common wheat (Triticum aestivum ssp.vulgare), with the combination of Rht1&rht8 genes, the analyzed characters being the hight of the strain (cm), the number of seeds/spike, seeds weight/spike (g), no. of spikes/m2, weight of a thousand seeds (WTS) (g) and no. of emerged plants/m2. Based on recorded data and statistical processing of those, they were identified a numbers of links between these characters, links quantified by using the correlation. Regarding the classification based on the average high of the strain, it was found that that there is a strong link between some characters too. Based on component analysis, the no. of seeds/spike and the seeds weight/spikes are components that influence in excess of 83% variance analysis, a total of five genotypes having positive scores for both factors.

  17. Assimilating surface observations in a four-dimensional variational Doppler radar data assimilation system to improve the analysis and forecast of a squall line case

    Science.gov (United States)

    Chen, Xingchao; Zhao, Kun; Sun, Juanzhen; Zhou, Bowen; Lee, Wen-Chau

    2016-10-01

    This paper examines how assimilating surface observations can improve the analysis and forecast ability of a fourdimensional Variational Doppler Radar Analysis System (VDRAS). Observed surface temperature and winds are assimilated together with radar radial velocity and reflectivity into a convection-permitting model using the VDRAS four-dimensional variational (4DVAR) data assimilation system. A squall-line case observed during a field campaign is selected to investigate the performance of the technique. A single observation experiment shows that assimilating surface observations can influence the analyzed fields in both the horizontal and vertical directions. The surface-based cold pool, divergence and gust front of the squall line are all strengthened through the assimilation of the single surface observation. Three experiments—assimilating radar data only, assimilating radar data with surface data blended in a mesoscale background, and assimilating both radar and surface observations with a 4DVAR cost function—are conducted to examine the impact of the surface data assimilation. Independent surface and wind profiler observations are used for verification. The result shows that the analysis and forecast are improved when surface observations are assimilated in addition to radar observations. It is also shown that the additional surface data can help improve the analysis and forecast at low levels. Surface and low-level features of the squall line—including the surface warm inflow, cold pool, gust front, and low-level wind—are much closer to the observations after assimilating the surface data in VDRAS.

  18. Data assimilation in the decision support system RODOS

    DEFF Research Database (Denmark)

    Rojas-Palma, C.; Madsen, H.; Gering, F.;

    2003-01-01

    . The process of combining model predictions and observations, usually referred to as data assimilation, is described in this article within the framework of the real time on-line decision support system (RODOS) for off-site nuclear emergency management in Europe. Data assimilation capabilities, based...... the system. This would in turn provide decision makers with uncertainty estimates taking into account both model and observation errors. This paper describes the methodology employed as well as results of some preliminary studies based on simulated data....... on Kalman filters, are under development for several modules of the RODOS system, including the atmospheric dispersion, deposition, food chain and hydrological models. The use of such a generic data assimilation methodology enables the propagation of uncertainties throughout the various modules of...

  19. Assimilating models and data to enhance predictions of shoreline evolution

    Science.gov (United States)

    Long, Joseph W.; Plant, Nathaniel G.

    2010-01-01

    A modeling system that considers both long- and short-term process-driven shoreline change is presented. The modeling system is integrated into a data assimilation framework that uses sparse observations of shoreline change to correct a model forecast and to determine unobserved model variables and free parameters. Application of the assimilation algorithm also provides quantitative statistical estimates of uncertainty that can be applied to coastal hazard and vulnerability assessments. Significant attention is given to the estimation of four non-observable quantities using the data assimilation framework that utilizes only one observable process (i.e. ,shoreline change). The general framework discussed here can be applied to many other geophysical processes by simply changing the model component to one applicable to the processes of interest.

  20. Impact of Assimilated and Interactive Aerosol on Tropical Cyclogenesis

    Science.gov (United States)

    Reale, O.; Lau, K. M.; daSilva, A.; Matsui, T.

    2014-01-01

    This article investigates the impact 3 of Saharan dust on the development of tropical cyclones in the Atlantic. A global data assimilation and forecast system, the NASA GEOS-5, is used to assimilate all satellite and conventional data sets used operationally for numerical weather prediction. In addition, this new GEOS-5 version includes assimilation of aerosol optical depth from the Moderate Resolution Imaging Spectroradiometer (MODIS). The analysis so obtained comprises atmospheric quantities and a realistic 3-d aerosol and cloud distribution, consistent with the meteorology and validated against Cloud-Aerosol Lidar and Infrared Pathfinder Satellite Observation (CALIPSO) and CloudSat data. These improved analyses are used to initialize GEOS-5 forecasts, explicitly accounting for aerosol direct radiative effects and their impact on the atmospheric dynamics. Parallel simulations with/without aerosol radiative effects show that effects of dust on static stability increase with time, becoming highly significant after day 5 and producing an environment less favorable to tropical cyclogenesis.