572 research outputs found

    A Standardised Procedure for Evaluating Creative Systems: Computational Creativity Evaluation Based on What it is to be Creative

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    Computational creativity is a flourishing research area, with a variety of creative systems being produced and developed. Creativity evaluation has not kept pace with system development with an evident lack of systematic evaluation of the creativity of these systems in the literature. This is partially due to difficulties in defining what it means for a computer to be creative; indeed, there is no consensus on this for human creativity, let alone its computational equivalent. This paper proposes a Standardised Procedure for Evaluating Creative Systems (SPECS). SPECS is a three-step process: stating what it means for a particular computational system to be creative, deriving and performing tests based on these statements. To assist this process, the paper offers a collection of key components of creativity, identified empirically from discussions of human and computational creativity. Using this approach, the SPECS methodology is demonstrated through a comparative case study evaluating computational creativity systems that improvise music

    Coordination of opposing sex-specific and core muscle groups regulates male tail posture during Caenorhabditis elegans male mating behavior

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    Background To survive and reproduce, animals must be able to modify their motor behavior in response to changes in the environment. We studied a complex behavior of Caenorhabditis elegans, male mating behavior, which provided a model for understanding motor behaviors at the genetic, molecular as well as circuit level. C. elegans male mating behavior consists of a series of six sub-steps: response to contact, backing, turning, vulva location, spicule insertion, and sperm transfer. The male tail contains most of the sensory structures required for mating, in addition to the copulatory structures, and thus to carry out the steps of mating behavior, the male must keep his tail in contact with the hermaphrodite. However, because the hermaphrodite does not play an active role in mating and continues moving, the male must modify his tail posture to maintain contact. We provide a better understanding of the molecular and neuro-muscular pathways that regulate male tail posture during mating. Results Genetic and laser ablation analysis, in conjunction with behavioral assays were used to determine neurotransmitters, receptors, neurons and muscles required for the regulation of male tail posture. We showed that proper male tail posture is maintained by the coordinated activity of opposing muscle groups that curl the tail ventrally and dorsally. Specifically, acetylcholine regulates both ventral and dorsal curling of the male tail, partially through anthelmintic levamisole-sensitive, nicotinic receptor subunits. Male-specific muscles are required for acetylcholine-driven ventral curling of the male tail but dorsal curling requires the dorsal body wall muscles shared by males and hermaphrodites. Gamma-aminobutyric acid activity is required for both dorsal and ventral acetylcholine-induced curling of the male tail and an inhibitory gamma-aminobutyric acid receptor, UNC-49, prevents over-curling of the male tail during mating, suggesting that cross-inhibition of muscle groups helps maintain proper tail posture. Conclusion Our results demonstrated that coordination of opposing sex-specific and core muscle groups, through the activity of multiple neurotransmitters, is required for regulation of male tail posture during mating. We have provided a simple model for regulation of male tail posture that provides a foundation for studies of how genes, molecular pathways, and neural circuits contribute to sensory regulation of this motor behavior

    Population genetics of trypanosoma brucei rhodesiense: clonality and diversity within and between foci

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    African trypanosomes are unusual among pathogenic protozoa in that they can undergo their complete morphological life cycle in the tsetse fly vector with mating as a non-obligatory part of this development. Trypanosoma brucei rhodesiense, which infects humans and livestock in East and Southern Africa, has classically been described as a host-range variant of the non-human infective Trypanosoma brucei that occurs as stable clonal lineages. We have examined T. b. rhodesiense populations from East (Uganda) and Southern (Malawi) Africa using a panel of microsatellite markers, incorporating both spatial and temporal analyses. Our data demonstrate that Ugandan T. b. rhodesiense existed as clonal populations, with a small number of highly related genotypes and substantial linkage disequilibrium between pairs of loci. However, these populations were not stable as the dominant genotypes changed and the genetic diversity also reduced over time. Thus these populations do not conform to one of the criteria for strict clonality, namely stability of predominant genotypes over time, and our results show that, in a period in the mid 1990s, the previously predominant genotypes were not detected but were replaced by a novel clonal population with limited genetic relationship to the original population present between 1970 and 1990. In contrast, the Malawi T. b. rhodesiense population demonstrated significantly greater diversity and evidence for frequent genetic exchange. Therefore, the population genetics of T. b. rhodesiense is more complex than previously described. This has important implications for the spread of the single copy T. b. rhodesiense gene that allows human infectivity, and therefore the epidemiology of the human disease, as well as suggesting that these parasites represent an important organism to study the influence of optional recombination upon population genetic dynamics

    Proteomic analysis of the Plasmodium male gamete reveals the key role for glycolysis in flagellar motility.

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    BACKGROUND: Gametogenesis and fertilization play crucial roles in malaria transmission. While male gametes are thought to be amongst the simplest eukaryotic cells and are proven targets of transmission blocking immunity, little is known about their molecular organization. For example, the pathway of energy metabolism that power motility, a feature that facilitates gamete encounter and fertilization, is unknown. METHODS: Plasmodium berghei microgametes were purified and analysed by whole-cell proteomic analysis for the first time. Data are available via ProteomeXchange with identifier PXD001163. RESULTS: 615 proteins were recovered, they included all male gamete proteins described thus far. Amongst them were the 11 enzymes of the glycolytic pathway. The hexose transporter was localized to the gamete plasma membrane and it was shown that microgamete motility can be suppressed effectively by inhibitors of this transporter and of the glycolytic pathway. CONCLUSIONS: This study describes the first whole-cell proteomic analysis of the malaria male gamete. It identifies glycolysis as the likely exclusive source of energy for flagellar beat, and provides new insights in original features of Plasmodium flagellar organization

    Neurobehavioral consequences of chronic intrauterine opioid exposure in infants and preschool children: a systematic review and meta-analysis

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    <b>Background</b><p></p> It is assumed within the accumulated literature that children born of pregnant opioid dependent mothers have impaired neurobehavioral function as a consequence of chronic intrauterine opioid use.<p></p> <b>Methods</b><p></p> Quantitative and systematic review of the literature on the consequences of chronic maternal opioid use during pregnancy on neurobehavioral function of children was conducted using the Meta-analysis of Observational Studies in Epidemiology (MOOSE) and the Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) guidelines. We searched Cinahl, EMBASE, PsychINFO and MEDLINE between the periods of January 1995 to January 2012.<p></p> <b>Results</b><p></p> There were only 5 studies out of the 200 identified that quantitatively reported on neurobehavioral function of children after maternal opioid use during pregnancy. All 5 were case control studies with the number of exposed subjects within the studies ranging from 33–143 and 45–85 for the controls. This meta-analysis showed no significant impairments, at a non-conservative significance level of p < 0.05, for cognitive, psychomotor or observed behavioural outcomes for chronic intra-uterine exposed infants and pre-school children compared to non-exposed infants and children. However, all domains suggested a trend to poor outcomes in infants/children of opioid using mothers. The magnitude of all possible effects was small according to Cohen’s benchmark criteria.<p></p> <b>Conclusions</b><p></p> Chronic intra-uterine opioid exposed infants and pre-school children experienced no significant impairment in neurobehavioral outcomes when compared to non-exposed peers, although in all domains there was a trend to poorer outcomes. The findings of this review are limited by the small number of studies analysed, the heterogenous populations and small numbers within the individual studies. Longitudinal studies are needed to determine if any neuropsychological impairments appear after the age of 5 years and to help investigate further the role of environmental risk factors on the effect of ‘core’ phenotypes

    A qualitative study of the learning processes in young physicians treating suicidal patients: from insecurity to personal pattern knowledge and self-confidence

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    <p>Abstract</p> <p>Background</p> <p>Little empirical work has been done in studying learning processes among newly educated physicians in the mental health field.</p> <p>The aim of the study was to shed light on the meaning of newly educated physicians' lived experiences of learning processes related to treating suicidal patients.</p> <p>Methods</p> <p>Thirteen newly educated physicians narrated their learning experiences while treating suicidal patients in their own practice. The interview texts were transcribed and interpreted using a phenomenological-hermeneutical method inspired by Ricoeur's philosophy.</p> <p>Results</p> <p>There was one main theme, four themes and eleven sub themes. The main theme was: Being in a transitional learning process. The themes and sub themes were: Preparing for practice (Getting tools and training skills, Becoming aware of one's own attitudes); Gaining experience from treating patients (Treating and following up patients over time, Storing memories and recognizing similarities and differences in patients); Participating in the professional community (Being an apprentice, Relating clinical stories and receiving feedback, Sharing emotions from clinical experiences, Receiving support from peers); and Developing personal competence (Having unarticulated awareness, Having emotional knowledge, Achieving self-confidence). The informants gave a detailed account of the learning process; from recognising similarities and differences in patients they have treated, to accumulating pattern knowledge, which then contributed to their personal feelings of competence and confidence. They described their personal competence with cognitive and emotional elements consisting of both articulated and less articulated knowledge. The findings are interpreted in relation to different learning theories that focus on both individual factors and the interaction with the learning environment.</p> <p>Conclusion</p> <p>This study provides additional information about learning experiences of young physicians during the critical transition phase from medical school to early professional life. Peers are used for both learning and support and might represent a more powerful resource in the learning process than previously recognized. Emotional experiences do not seem to be adequately focused upon in supervision, which obviously has relevance both for learning and for the well-being of young professionals. The study indicates some areas of the educational system that could profitably be expanded including stimulating more systematically to critical reflection on and in practice, attention to feelings in the reflective process and provision of more performance feedback to young physicians.</p

    Cranial Growth and Variation in Edmontosaurs (Dinosauria: Hadrosauridae): Implications for Latest Cretaceous Megaherbivore Diversity in North America

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    The well-sampled Late Cretaceous fossil record of North America remains the only high-resolution dataset for evaluating patterns of dinosaur diversity leading up to the terminal Cretaceous extinction event. Hadrosaurine hadrosaurids (Dinosauria: Ornithopoda) closely related to Edmontosaurus are among the most common megaherbivores in latest Campanian and Maastrichtian deposits of western North America. However, interpretations of edmontosaur species richness and biostratigraphy have been in constant flux for almost three decades, although the clade is generally thought to have undergone a radiation in the late Maastrichtian. We address the issue of edmontosaur diversity for the first time using rigorous morphometric analyses of virtually all known complete edmontosaur skulls. Results suggest only two valid species, Edmontosaurus regalis from the late Campanian, and E. annectens from the late Maastrichtian, with previously named taxa, including the controversial Anatotitan copei, erected on hypothesized transitional morphologies associated with ontogenetic size increase and allometric growth. A revision of North American hadrosaurid taxa suggests a decrease in both hadrosaurid diversity and disparity from the early to late Maastrichtian, a pattern likely also present in ceratopsid dinosaurs. A decline in the disparity of dominant megaherbivores in the latest Maastrichtian interval supports the hypothesis that dinosaur diversity decreased immediately preceding the end Cretaceous extinction event

    Ifugao males, learning and teaching for the improvement of maternal and child health status in the Philippines: an evaluation of a program

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    <p>Abstract</p> <p>Background</p> <p>Improving Maternal and Child Health (MCH) is a prioritized global agenda in achieving the United Nations Millennium Development Goal 5. In this challenge, involving males has been an important agenda, and a program with such intent was conducted in <it>Alfonso Lista, Ifugao</it>, of the Philippines. The objectives of this study were: (1) to evaluate the effectiveness in knowledge, attitude, and practice before and after a MCH session; (2) to evaluate the session's effectiveness in relation to socio-demographic characteristics; and (3) to examine if males who have learned about MCH topics can teach another group of males.</p> <p>Methods</p> <p>A male community representative who received a lecture from the health office staff was assigned to teach a group of community males [Group 1, N = 140] in 5 sessions, using educational materials. 10 male volunteers from Group 1 then taught a different group of males [Group 2, N = 105] in their own <it>barangays </it>(villages). To evaluate its effectiveness, a self-administered questionnaire survey pertaining knowledge, attitude and practice regarding MCH was conducted at three different time points: before the session (Time 1, T1), after the session (Time 2, T2), and 3 months following the session (Time 3, T3). A repeated measures analysis of variance was conducted to test for changes over time and its interaction effect between specific socio-demographic variables.</p> <p>Results</p> <p>In Group 1, there was a significant positive increase in knowledge score over time at T1-T2 and T1-T3 (<it>p </it>< 0.001). For attitude, the score increased only at T1-T2 (<it>p </it>= 0.027). The effectiveness in knowledge and attitude did not vary by socio-demographic characteristics. As for practice, majority of the participants reported that they had talked about MCH topics in their community and assisted a pregnant woman in some ways. A comparison between Group 1 and Group 2 revealed that Group 2 had similar effectiveness as Group 1 in knowledge improvement immediately after the session (<it>p </it>< 0.001), but no such improvement in the attitude score.</p> <p>Conclusion</p> <p>Although the change in attitude needs further assessment, this strategy of continuous learning and teaching of MCH topics within community males is shown to improve knowledge and has a potential to uplift the MCH status, including the reduction of maternal deaths, in <it>Alfonso Lista, Ifugao, Philippines</it>.</p
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