628 resultados para deceptive pollination
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Pollination-dependent fruit trees grown in home gardens play an important role in the agricultural based economy of Central Asian countries, yet little is known about the status of pollinator communities, the cultivated plant composition or the factors that influence management practices in Kyrgyz home garden agroecosystems. As agricultural systems are human created and managed, a logical approach to their study blends anthropological and ecological methods, an ethnoecological approach. Over three years, I investigated how species richness and abundance of Hymenoptera, cultivated plants, and home garden management were related using quantitative and qualitative methods in the Issyk-kul Man and Biosphere reserve. Structured surveys were undertaken with heads of households using a random sample stratified by village. Gardens were then mapped with participation of household members to inventory edible species in gardens, most of which are pollinator-dependent, and to compare home garden diversity as reported by respondents during interviews. Apple diversity was studied to the variety level to understand respondents’ classification system in the context of in situ agrobiodiversity conservation. Household members identified 52 edible plant species when mapping the garden, compared with 32 reported when interviewed. The proportion of plant species received from others through exchange and the number of plots cultivated significantly explained the variation in edible plant diversity among gardens. Insects were sampled in gardens and orchards to determine potential pollinator community composition and the effect of different management practices on Hymenoptera richness and abundance. I collected 756 Hymenoptera individuals (56 bee; 12 wasp species); 12 species were new records for Kyrgyzstan or within Kyrgyzstan. Economic pressures to intensify cultivation could impact management practices that currently promote diversity. A home garden development initiative was undertaken to study management practice improvement. Participants in the initiative had higher adoption rates than controls of management practices that improve long-term yield, ecological sustainability and stability of home gardens. Home gardens, as currently managed, support abundant and diverse pollinator communities and have high cultivated plant diversity with few differences in community composition between garden management types.
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The current study applied classic cognitive capacity models to examine the effect of cognitive load on deception. The study also examined whether the manipulation of cognitive load would result in the magnification of differences between liars and truth-tellers. In the first study, 87 participants engaged in videotaped interviews while being either deceptive or truthful about a target event. Some participants engaged in a concurrent secondary task while being interviewed. Performance on the secondary task was measured. As expected, truth tellers performed better on secondary task items than liars as evidenced by higher accuracy rates. These results confirm the long held assumption that being deceptive is more cognitively demanding than being truthful. In the second part of the study, the videotaped interviews of both liars and truth-tellers were shown to 69 observers. After watching the interviews, observers were asked to make a veracity judgment for each participant. Observers made more accurate veracity judgments when viewing participants who engaged in a concurrent secondary task than when viewing those who did not. Observers also indicated that participants who engaged in a concurrent secondary task appeared to think harder than participants who did not. This study provides evidence that engaging in deception is more cognitively demanding than telling the truth. As hypothesized, having participants engage in a concurrent secondary task led to the magnification of differences between liars and truth tellers. This magnification of differences led to more accurate veracity rates in a second group of observers. The implications for deception detection are discussed.
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The authors would like to express their gratitude to organizations and people that supported this research. Piotr Omenzetter’s work within the Lloyd’s Register Foundation Centre for Safety and Reliability Engineering at the University of Aberdeen is supported by Lloyd’s Register Foundation. The Foundation helps to protect life and property by supporting engineering-related education, public engagement and the application of research. Ben Ryder of Aurecon and Graeme Cummings of HEB Construction assisted in obtaining access to the bridge and information for modelling. Luke Williams and Graham Bougen, undergraduate research students, assisted with testing.
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Making decisions is fundamental to everything we do, yet it can be impaired in various disorders and conditions. While research into the neural basis of decision-making has flourished in recent years, many questions remain about how decisions are instantiated in the brain. Here we explored how primates make abstract decisions and decisions in social contexts, as well as one way to non-invasively modulate the brain circuits underlying decision-making. We used rhesus macaques as our model organism. First we probed numerical decision-making, a form of abstract decision-making. We demonstrated that monkeys are able to compare discrete ratios, choosing an array with a greater ratio of positive to negative stimuli, even when this array does not have a greater absolute number of positive stimuli. Monkeys’ performance in this task adhered to Weber’s law, indicating that monkeys—like humans—treat proportions as analog magnitudes. Next we showed that monkeys’ ordinal decisions are influenced by spatial associations; when trained to select the fourth stimulus from the bottom in a vertical array, they subsequently selected the fourth stimulus from the left—and not from the right—in a horizontal array. In other words, they begin enumerating from one side of space and not the other, mirroring the human tendency to associate numbers with space. These and other studies confirmed that monkeys’ numerical decision-making follows similar patterns to that of humans, making them a good model for investigations of the neurobiological basis of numerical decision-making.
We sought to develop a system for exploring the neuronal basis of the cognitive and behavioral effects observed following transcranial magnetic stimulation, a relatively new, non-invasive method of brain stimulation that may be used to treat clinical disorders. We completed a set of pilot studies applying offline low-frequency repetitive transcranial magnetic stimulation to the macaque posterior parietal cortex, which has been implicated in numerical processing, while subjects performed a numerical comparison and control color comparison task, and while electrophysiological activity was recorded from the stimulated region of cortex. We found tentative evidence in one paradigm that stimulation did selectively impair performance in the number task, causally implicating the posterior parietal cortex in numerical decisions. In another paradigm, however, we manipulated the subject’s reaching behavior but not her number or color comparison performance. We also found that stimulation produced variable changes in neuronal firing and local field potentials. Together these findings lay the groundwork for detailed investigations into how different parameters of transcranial magnetic stimulation can interact with cortical architecture to produce various cognitive and behavioral changes.
Finally, we explored how monkeys decide how to behave in competitive social interactions. In a zero-sum computer game in which two monkeys played as a shooter or a goalie during a hockey-like “penalty shot” scenario, we found that shooters developed complex movement trajectories so as to conceal their intentions from the goalies. Additionally, we found that neurons in the dorsolateral and dorsomedial prefrontal cortex played a role in generating this “deceptive” behavior. We conclude that these regions of prefrontal cortex form part of a circuit that guides decisions to make an individual less predictable to an opponent.
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This dissertation examines the corpse as an object in and of American hardboiled detective fiction written between 1920 and 1950. I deploy several theoretical frames, including narratology, body-as-text theory, object relations theory, and genre theory, in order to demonstrate the significance of objects, symbols, and things primarily in the clever and crafty work of Dashiell Hammett (1894-1961) and Raymond Chandler (1888-1959), but also touching on the writings of their lesser known accomplices. I construct a literary genealogy of American hardboiled detective fiction originating in the writings of Edgar Allan Poe, compare the contributions of classic or Golden Age detective fiction in England, and describe the socio-economic contexts, particularly the predominance of the “pulps,” that gave birth to the realism of the Hardboiled School. Taking seriously Chandler’s obsession with the art of murder, I engage with how authors pre-empt their readers’ knowledge of the tricks of the trade and manipulate their expectations, as well as discuss the characteristics and effect of the inimitable hardboiled style, its sharpshooting language and deadpan humour. Critical scholarship has rarely addressed the body and figure of the corpse, preferring to focus instead on the machinations of the femme fatale, the performance of masculinity, or the prevalence of violence. I cast new light on the world of hardboiled detective fiction by dissecting the corpse as the object that both motivates and de-composes (or rots away from) the narrative that makes it signify. I treat the corpse as an inanimate object, indifferent to representation, that destabilizes the integrity and self-possession, as well as the ratiocination, of the detective who authors the narrative of how the corpse came to be. The corpse is all deceptive and dangerous surface rather than the container of hidden depths of life and meaning that the detective hopes to uncover and reconstruct. I conclude with a chapter that is both critical denouement and creative writing experiment to reveal the self-reflexive (and at times metafictional) dimensions of hardboiled fiction. My dissertation, too, in the manner of hardboiled fiction, hopes to incriminate my readers as much as enlighten them.
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Sounds offer a rich source of information about events taking place in our physical and social environment. However, outside the domains of speech and music, little is known about whether humans can recognize and act upon the intentions of another agent’s actions detected through auditory information alone. In this study we assessed whether intention can be inferred from the sound an action makes, and in turn, whether this information can be used to prospectively guide movement. In two experiments experienced and novice basketball players had to virtually intercept an attacker by listening to audio recordings of that player’s movements. In the first experiment participants had to move a slider, while in the second one their body, to block the perceived passage of the attacker as they would in a real basketball game. Combinations of deceptive and non-deceptive movements were used to see if novice and/or experienced listeners could perceive the attacker’s intentions through sound alone. We showed that basketball players were able to more accurately predict final running direction compared to non-players, particularly in the second experiment when the interceptive action was more basketball specific. We suggest that athletes present better action anticipation by being able to pick up and use the relevant kinematic features of deceptive movement from event-related sounds alone. This result suggests that action intention can be perceived through the sound a movement makes and that the ability to determine another person’s action intention from the information conveyed through sound is honed through practice.
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This paper draws on some of the preliminary findings of a small pilot study which aimed to discover what evidentiary challenges a range of practitioners with experience of different international trials faced in the cases they were involved in, and what practices were developed to deal with these challenges. The findings in this study are based on the data collected from The Hague-based institutions, the ICC, the ICTY, the ICTY and ICTR Appeals Chamber, and the Special Tribunal for the Lebanon (STL). It is argued that professionals moving from institution to institution are engaged in a process of cross-pollination which itself influences the practices that develop, although a common understanding of certain evidentiary issues in international trials remains fragmented and at times elusive.
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The paper describes the design and implementation of a novel low cost virtual rugby decision making interactive for use in a visitor centre. Original laboratory-based experimental work in decision making in rugby, using a virtual reality headset [1] is adapted for use in a public visitor centre, with consideration given to usability, costs, practicality and health and safety. Movement of professional rugby players was captured and animated within a virtually recreated stadium. Users then interact with these virtual representations via use of a lowcost sensor (Microsoft Kinect) to attempt to block them. Retaining the principles of perception and action, egocentric viewpoint, immersion, sense of presence, representative design and game design the system delivers an engaging and effective interactive to illustrate the underlying scientific principles of deceptive movement. User testing highlighted the need for usability, system robustness, fair and accurate scoring, appropriate level of difficulty and enjoyment.
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ARAUJO, Afranio Cesar de et al. Síndromes de polinização ocorrentes em uma área de Mata Atlântica, Paraíba, Brasil. Biotemas, Florianopolis, v. 4, n. 22, p.83-94, dez. 2009. Disponível em:
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Natural selection mediated by pollinators has influenced the evolution of floral diversity of the flowering plants (angiosperms). The scope of this thesis was to study: 1) phenotypic selection, 2) mating systems, and 3) floral shifts involved in plant speciation. Model plant species were Platanthera bifolia and P. chlorantha (Orchidaceae). These orchids are moth-pollinated, strictly co-sexual (bisexual flowers), and produce a spike that displays 10-20 white flowers. I explored the influence of characters on plant fitness by using multiple linear regressions. Pollen removal (male fitness) and fruit set (female fitness) increased with more flowers per plant in three P. bifolia populations. There was selection towards longer spurs in a dry year when average spur length was shorter than in normal-wet years. Female function was sensitive to drought, which enabled an application of the male function hypothesis of floral evolution (Bateman's principle). The results show that selection may vary between populations, years, and sex-functions. I examined inbreeding by estimating levels of geitonogamy (self-pollination between flowers of an individual) with an emasculation method in two P. bifolia populations. Geitonogamy did not vary with inflorescence size. Levels of geitonogamy was 20-40% in the smaller, but non-significant in the larger population. This may relate to lower number of possible mates and pollinator activity in the smaller population. Platanthera bifolia exhibits the ancestral character state of tongue-attachment of pollinia on the pollinator. Its close relative P. chlorantha attaches its pollinia onto the pollinator's eyes. To explore the mechanism of a floral shift, pollination efficiency and speed was compared between the two species. The results showed no differences in pollination efficiency, but P. chlorantha had faster pollen export and import. Efficiency of pollination in terms of speed may cause floral shifts, and thus speciation.
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Land-use change and intensification threaten bee populations worldwide, imperilling pollination services. Global models are needed to better characterise, project, and mitigate bees' responses to these human impacts. The available data are, however, geographically and taxonomically unrepresentative; most data are from North America and Western Europe, overrepresenting bumblebees and raising concerns that model results may not be generalizable to other regions and taxa. To assess whether the geographic and taxonomic biases of data could undermine effectiveness of models for conservation policy, we have collated from the published literature a global dataset of bee diversity at sites facing land-use change and intensification, and assess whether bee responses to these pressures vary across 11 regions (Western, Northern, Eastern and Southern Europe; North, Central and South America; Australia and New Zealand; South East Asia; Middle and Southern Africa) and between bumblebees and other bees. Our analyses highlight strong regionally-based responses of total abundance, species richness and Simpson's diversity to land use, caused by variation in the sensitivity of species and potentially in the nature of threats. These results suggest that global extrapolation of models based on geographically and taxonomically restricted data may underestimate the true uncertainty, increasing the risk of ecological surprises.
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ARAUJO, Afranio Cesar de et al. Síndromes de polinização ocorrentes em uma área de Mata Atlântica, Paraíba, Brasil. Biotemas, Florianopolis, v. 4, n. 22, p.83-94, dez. 2009. Disponível em:
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Les pollinisateurs indigènes sont importants pour la production de canneberges. Ils sont pourtant menacés par les pratiques agricoles qui s’intensifient. Pour établir un plan de conservation efficace, une meilleure connaissance des facteurs intrinsèques aux exploitations est essentielle. L’objectif principal de cette étude était de déterminer la diversité et abondance des abeilles et syrphes retrouvées en cannebergières. Quinze fermes ont été échantillonnées selon la régie de culture, le type de sol et le type d’habitat naturel retrouvé près des cannebergières. Des pièges-bols disposés en transect ainsi que l’utilisation de filet entomologique ont été utilisés pour échantillonner les pollinisateurs. Au total, 135 espèces de pollinisateurs indigènes ont été capturées en 2013 et 2014. Le type de sol ainsi que l’habitat naturel influençaient les communautés de pollinisateurs, alors que la régie de culture ne les affectait pas. L’abeille Melitta americana, spécialiste du pollen de canneberge, a été capturée plus souvent dans les tourbières.
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Plant reproduction depends on the concerted activation of many genes to ensure correct communication between pollen and pistil. Here, we queried the whole transcriptome of Arabidopsis (Arabidopsis thaliana) in order to identify genes with specific reproductive functions. We used the Affymetrix ATH1 whole genome array to profile wild-type unpollinated pistils and unfertilized ovules. By comparing the expression profile of pistils at 0.5, 3.5, and 8.0 h after pollination and applying a number of statistical and bioinformatics criteria, we found 1,373 genes differentially regulated during pollen-pistil interactions. Robust clustering analysis grouped these genes in 16 time-course clusters representing distinct patterns of regulation. Coregulation within each cluster suggests the presence of distinct genetic pathways, which might be under the control of specific transcriptional regulators. A total of 78% of the regulated genes were expressed initially in unpollinated pistil and/or ovules, 15% were initially detected in the pollen data sets as enriched or preferentially expressed, and 7% were induced upon pollination. Among those, we found a particular enrichment for unknown transcripts predicted to encode secreted proteins or representing signaling and cell wall-related proteins, which may function by remodeling the extracellular matrix or as extracellular signaling molecules. A strict regulatory control in various metabolic pathways suggests that fine-tuning of the biochemical and physiological cellular environment is crucial for reproductive success. Our study provides a unique and detailed temporal and spatial gene expression profile of in vivo pollen-pistil interactions, providing a framework to better understand the basis of the molecular mechanisms operating during the reproductive process in higher plants.
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Protective cropping could be an effective system for growing specialty melons in the dry tropics of North Queensland. The growing system could reduce outdoor risks for production loss, improve fruit quality, increase yield per m2, allow production offseason, and used for supplying niche markets in a segment of the larger melon market in Australia. First evaluations in Giru, Queensland, included seven cultivars of fruit types 'Galia', 'Hami', 'Charentais', small 'Canary', and 'Rockmelon', transplanted July 25, 2013 under a high polyethylene-covered tunnel. Plants were grown at a density of 2.8 plants m-2 in containers filled with volcanic rock and irrigated with a complete nutrient solution. Pruning and trellising was done to a single vertical stem, keeping lateral shoots on the main stem after the 7th leaf node. After bearing small fruit, lateral shoots were cut off after their second or third leaf node. To facilitate insect pollination, a screen window in the tunnel was left partially opened. On November 20 the cultivars had combined marketable yields that ranged from 2.8 to 8.2 fruits m-2 and 3.1 to 7.8 kg m-2. Total soluble solids levels in fruit ranged from 6 to 13 °Brix. Cultivars 'Tempo' ('Galia'), 'Tikal' ('Canary') and 'Sultan' ('Charentais') had fruit yields that were up to 2.6 times greater than yields commonly achieved with field-grown rockmelon crops. Sugar levels in fruits and marketable yields may be increased with changes in fertigation management. Promising results in this first evaluation justify examination of a greater number of genetic materials, in addition to the development of economic feasibility studies and further adaptive research to refine crop recommendations for growing melons in protective cropping systems.