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Priddis, Edmund R. "Niche Separation Along Environmental Gradients as a Mechanism to Promote the Coexistence of Native and Invasive Species." Diss., CLICK HERE for online access, 2007. http://contentdm.lib.byu.edu/ETD/image/etd2199.pdf.
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Esquivel, Palma Carlos Josue. "TOXICOLOGICAL INTERACTIONS BETWEEN THIAMETHOXAM, APHIDS, AND PREDATORY NATURAL ENEMIES." The Ohio State University, 2019. http://rave.ohiolink.edu/etdc/view?acc_num=osu1574435608424832.
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Geitzenauer, Heather Lyn 1969. "Tritrophic interactions: Effects of caterpillar host plants on predatory paper wasps." Thesis, The University of Arizona, 1993. http://hdl.handle.net/10150/278376.
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The effects of sunflower (Helianthus annuus) and groundcherry (Physalis pubescens), two hosts of the tobacco budworm (Heliothis virescens), on predation by paper wasps (Polistes arizonensis) were examined. Initially it was found that P. arizonensis foragers took more caterpillars from H. annuus plants than P. pubescens in paired-choice tests. Regarding physical aspects of the plants, wasps took longer to locate prey on artificial plants with higher leaf surface areas and gave up searching faster on artificial plants with more complex architectures. In paired-choice tests for chemical effects, wasps chose more caterpillars within H. annuus odor than in P. pubescens odor. They also chose more H. annuus-reared larvae than P. pubescens-reared larvae when they were presented without plants. Predator handling times were affected by the amount of food in the caterpillar gut, with a slight trend depending on what plant species was present in the caterpillar gut.
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Du, Toit Michelle. "Predatory interactions between Cape fur seals and seabirds at Ichaboe Island, Namiba." Diss., Pretoria : [s.n.], 2002. http://upetd.up.ac.zs/thesis/available/etd-11212005-150700/.
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Wilson, Rebecca. "Investigating the Interaction of Monoamines and Diel Rhythmicity on Anti-Predator Behavior in an Orb-Weaving Spider, Larinioides cornutus (Araneae: Araneae)." Digital Commons @ East Tennessee State University, 2018. https://dc.etsu.edu/etd/3441.
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Circadian rhythms are ubiquitous among organisms, influencing a wide array of physiological processes and behaviors including aggression. While many neurophysiological mechanisms are involved in the regulation of aggressive behaviors, relatively few studies have investigated the underlying components involved in the interplay between circadian rhythms and aggression. Spiders are an ideal model system for studying circadian regulation of aggression as they are ecologically both predators and prey. Recent studies have revealed a nocturnal orb- weaving spider Larinioides cornutus exhibits a diel and circadian rhythm in anti-predator behavior (i.e. boldness) that can be manipulated by administration of octopamine (OA) and serotonin (5- HT). Dosing of OA increases boldness of an individual while 5-HT decreases boldness levels. Thus, it appears the serotonergic and octopaminergic system are playing a key role in the daily fluctuations of boldness. This study took a holistic approach to investigate OA and 5-HT levels of head tissue and hemolymph (i.e. blood) as well as the genes involved in synthesis, signaling, and degradation of these monoamines throughout the day (0100, 0700, 1300, and 1900 hours) using HPLC-ED and RNA-sequencing. Although endogenous and circulating levels of OA did not significantly fluctuate, putative transcripts involved in synthesis and signaling did increase in relative expression levels at dusk when L. cornutus begins to actively forage for prey. Endogenous and circulating levels of 5-HT also did not significantly change at the four different time points, but clear patterns of upregulation of 5-HT synthesis enzymes as well as some receptor transcripts were upregulated during the day when L. cornutus would be mostly inactive in its retreat. Lastly, monoamine oxidase, a major catabolic enzyme of monoamines in vertebrates and some invertebrates, was identified in L. cornutus and exhibited substrate specificity for OA compared to 5-HT. Together with the higher enzymatic activity at mid-day compared to dusk, MAO appears to be playing a significant role in regulating the OA and 5-HT signaling in L. cornutus. In conclusion, these results allow a unique preliminary perspective on how OA and 5-HT are influencing the diel shifts in aggression-related behaviors in an ecologically dynamic arthropod.
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Jawor, Jodie M. "Aggressive interactions and behaviors in house sparrow (Passer domesticus) flocks." Virtual Press, 1998. http://liblink.bsu.edu/uhtbin/catkey/1117106.
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This study addressed aggressive interactions, and some of the behaviors associated with them, in House Sparrow flocks. The evidence suggests that females are the consistently dominant sex, which does not concur with the current idea of alternating dominance in House Sparrows. Another purpose of this study was to determine if predictions concerning the type of interaction and level of aggression displayed could be made for interacting House Sparrows. I feel that accurate predictions can be made when several factors are taken into account: time of year, sex, and the age of birds at the food resource. In this study adult female House Sparrows dominated males from fall through spring, even when males increased their rate of initiating interactions during winter. Across all interaction types, mid-level aggression was used most often and only in male intrasexual interactions was high-level aggression more common than expected. Juvenile birds, mainly males, change flock dynamics in the fall by eliciting aggressive interactions.Department of Biology
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Porto, Morgana Maria Fonseca. "Intraguild interactions between the predatory mites Neoseiulus californicus and Phytoseiulus macropilis (Acari: Phytoseiidae)." Universidade Federal de Viçosa, 2017. http://www.locus.ufv.br/handle/123456789/11825.
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Conselho Nacional de Desenvolvimento Científico e Tecnológico
Os ácaros predadores são comumente usados como agentes de controle biológico e as espécies Phytoseiulus macropilis e Neoseiulus californicus têm sido consideradas para serem liberadas em conjunto para controlar uma importante praga, o ácaro rajado Tetranychus urticae. Porque predadores que interagem podem interferir uns com os outros, um passo importante para a liberação bem-sucedida de múltiplos predadores em programas de controle biológico requer determinar como os predadores respondem à presença uns dos outros e se eles estão envolvidos em interações intraguilda. Diante disso, inicialmente, foi investigado se esses dois ácaros predadores evitam a presença um do outro. Sabe-se que predadores e parasitoides podem usar voláteis associados à presença de espécies competidoras quando forrageiam por áreas com presas ou hospedeiros. Portanto, foi analisado se as duas espécies de predadores usam substâncias voláteis que emanam de plantas com presas e heteroespecíficos para evitar locais de presa com a outra espécie de predador. Além disso, foi avaliado se esses predadores interagem através da predação intraguilda, em que predadores competidores matam e comem-se uns aos outros. No entanto, como não há consenso em relação aos critérios para avaliar a ocorrência de tal interação, primeiro foi explorado os critérios existentes e então foi sugerido diretrizes para o desenho de experimentos. Com base nessas diretrizes, foi investigado tanto a capacidade de P. macropilis e N. californicus para matar os estágios da outra espécie como a capacidade de se beneficiar alimentando-se destes estágios, ambos pré-requisitos para a ocorrência de predação intraguilda. As descobertas mais importantes sobre as possíveis interações entre esses predadores são que nenhum dos predadores usou voláteis para evitar locais de presas ocupadas pelos heterospecíficos. No entanto, eles se envolveram em predação intraguilda recíproca. Além disso, foi mostrado que a ontogenia claramente desempenhou um papel crítico na determinação da ocorrência de predação intraguilda dentro deste sistema de predadores. Foi discutido as possíveis explicações para não se evitar os odores produzidos e a interação entre estágios ontogênicos e interações intraguilda.
Predatory mites are commonly used as biological control agents and the species Phytoseiulus macropilis and Neoseiulus californicus have been considered to be released together to control an important pest, the two-spotted spider mite Tetranychus urticae. Because interacting predators may interfere with each other, an important step towards the implementation of successful release of multiple predators in biological control programs requires to resolve how predators respond to the presence of each other and whether they are involved in intraguild interactions. Given this, initially, I investigated whether these two predatory mites avoid the presence of each other. It is known that predators and parasitoids can use volatiles associated with the presence of competing species when foraging for patches with prey or hosts. I therefore investigated whether the two predator species use volatiles emanating from plants with prey and heterospecifics to avoid prey patches with the other predator species. Furthermore, I assessed whether these predators interact trough intraguild predation, in which competing predators also kill and eat each other. However, because there is no consensus regarding criteria to evaluate the occurrence of such interaction, I first explored existing criteria and suggested guidelines for the design of experiments. Based on these guidelines, I subsequently evaluated both the capacity of P. macropilis and N. californicus to kill stages of the other species and the capacity to benefit from feeding on these stages, both prerequisites for the occurrence of intraguild predation. The most important findings regarding the possible interactions among these predators are that neither of the predators used volatiles to avoid prey patches occupied by the heterospecific predators. However, they did engage in reciprocal intraguild predation. Moreover, I show that ontogeny clearly played a critical role in determining the occurrence of intraguild predation within this predator system. I discuss the possible explanations for the lack of odour-mediated avoidance and the interplay between ontogenetic stages and intraguild interactions.
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Lourenço, Rui Nascimento Fazenda. "Predatory interactions among vertebrate top predators superpredation and intraguild predation by large raptors." Doctoral thesis, Universidade de Évora, 2011. http://hdl.handle.net/10174/14789.
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Nesta tese estudaram-se as interacções predatórias entre vertebrados predadores de topo
(predação intraguilda e superpredação), utilizando quatro aves de rapina de grande porte como
modelos de superpredadores: Bufo-real, Açor, Águia-real, e Águia de Bonelli. A superpredação em
aves de rapina é um fenómeno abrangente, que pode variar entre espécies, e mais frequente em
paisagens mais humanizadas. Os meso-predadores não são recursos energeticamente relevantes para
as aves de rapina, e o seu consumo está associado à diversificação da dieta resultante da diminuição
das presas habituais. A eliminação de competidores e potenciais predadores são outros factores que
podem aumentar a frequência da superpredação. O aumento da percentagem de meso-predadores na
dieta está associado a menor sucesso reprodutor e maiores níveis de acumulação de mercúrio nas
aves de rapina. O risco de predação pode levar um meso-predador (Coruja-do-mato) a diminuir a
sua actividade vocal de modo a estar menos exposto ao predador intraguilda; ABSTRACT: This thesis analyses predatory interactions among vertebrate top predadores (intraguild
predation and superpredation), using four large raptors as superpredator models: eagle owl,
goshawk, golden eagle and Bonelli's eagle. Superpredation in raptors is a widespread phenomenon,
that can vary between species, and that is more frequent in human-altered landscapes.
Mesopredators are not energetically relevant resources for raptors, and their consumption is related
to diet diversification as a result of the decline of staple prey. Competitor and predator removal are
additional factors that can cause an increase in superpredation rates. The increase of mesopredators
in the diet of raptors is associated to lower breeding success and higher levels of mercury
contamination. Predation risk can drive a mesopredator (tawny owl) to reduce its vocal activity in
order to be less exposed to its intraguild predator.
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Crawford, N. Lynn. "The emotional responses of aggressive and withdrawn preschoolers to peer interactions." Thesis, McGill University, 1993. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=41564.
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The emotions of aggressive and withdrawn children were examined in object-conflict and group-entry situations. Izard's (1977) differential theory of emotion suggests that aggressive children should have more hostile emotions, and withdrawn children more depressive emotions. Wright and Mischel's (1987) conditional approach to dispositional constructs suggests that aggressive children's hostility would be most evident during object-conflict, and withdrawn children's depressive responses most evident during group entry. Four- and 5-year-old boys and girls (N = 128) were assigned to aggressive, withdrawn, or control groups according to teachers' behaviour ratings. Interviews about children's emotional experiences in hypothetical object-conflict and group-entry situations failed to yield predicted group and situation differences. However, during semi-structured object-conflict and group-entry situations, aggressive children displayed more intense anger and more frequent anger blends, while withdrawn children were observed to show more intense sadness and more frequent fear-sadness blends. Displays of negative affect were related in theoretically meaningful ways to patterns of children's social behaviour. Failure to find situational specificity suggests that affective features of children's social competence may operate at a general level.
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Seccareccia, Ivana [Verfasser], Markus [Gutachter] Nett, Gabriele Gutachter] Diekert, and Elke [Gutachter] [Dittmann. "Unraveling predatory-prey interactions between bacteria / Ivana Seccareccia ; Gutachter: Markus Nett, Gabriele Diekert, Elke Dittmann." Jena : Friedrich-Schiller-Universität Jena, 2016. http://d-nb.info/1177611481/34.
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Bailey, R. J. E. "Predatory interactions between the invasive amphipod Gammarus tigrinus and the native Opossum shrimp Mysis relicta." Thesis, Queen's University Belfast, 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.368463.
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Myrick-Bragg, Kennesha. "Effects of Olfactory Cues on the Movement Behavior of the Predatory Beetle Calosoma wilcoxi." VCU Scholars Compass, 2016. http://scholarscompass.vcu.edu/etd/4437.
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Arthropod predators often use prey and conspecific cues to make foraging decisions. Calosoma wilcoxi (Leconte) is a voracious predatory beetle that specializes on lepidopteran larvae often found in the forest canopy, including the fall cankerworm. This study tested the hypothesis that C. wilcoxi uses olfactory cues to detect prey and conspecifics. A Y-tube olfactometer was used to test attractiveness to larvae, larval frass, conspecific cues, and volatiles from herbivore-damaged white oak leaves. C. wilcoxi did not preferentially choose the treatment in any of the experiments. There was no difference in mean time spent in the treatment or control arm for any of the cues assayed. The time to choose the treatment was significantly shorter in the female conspecific experiment only. I found no evidence that C. wilcoxi uses olfaction to locate prey; however, C. wilcoxi is attracted to conspecifics. C. wilcoxi may use conspecific cues to make informed foraging decisions.
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Mott, Cy Larue. "Biotic and abiotic influences on aggressive interactions within larval Ambystoma assemblages." OpenSIUC, 2010. https://opensiuc.lib.siu.edu/dissertations/140.
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Coexistence among ecologically similar species is often facilitated through temporal or spatial partitioning mechanisms that reduce or eliminate direct interaction. However, in many communities exhibiting guild structure, wherein potential competitors may also prey on one another, sympatric relationships persist despite species' similar life history strategies, spatial and temporal restrictions imposed by ephemeral habitats, and resource limitations that promote competition and predation. To identify the ecological roles of species-specific behavioral patterns within aquatic guilds, I quantified larval intraspecific agonistic behavior among two species of intraguild (IG) predators, Ambystoma opacum and A. tigrinum, and their shared intraguild prey, A. maculatum. All species exhibited similar ontogenetic patterns of aggression, characterized by peaks of aggression early in development and subsequent gradual decreases through metamorphosis. However, the intensity of aggression varied considerably among guild species through development, as did behavioral responses to varying levels of ambient water temperature, invertebrate prey density, and presence of predatory odonate naiads. The observed patterns suggest that guild species, despite morphological and physiological similarities, exhibit unique behavioral responses through ontogeny and in response to habitat variables, suggesting that temporally staggered breeding phenologies have contributed to behavioral divergence among these sympatric congeners. However, in situ observations of larval behavior, although largely in agreement with laboratory results on timing of increased aggression, indicated that IG predators exhibited pond-level species partitioning and do not necessarily co-occur despite being regarded as sympatric. These results, taken together with observed species-specific impacts of IG predators on IG prey, suggest that ecologically similar IG predators exert widely differing predatory pressure on shared prey, and that similarities among guild species may ultimately result in habitat partitioning across local scales.
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Mitchell, Andrea Lauren. "Conflict Management Styles and Aggressive Communication in Email: An Examination of Organizational Interactions." University of Akron / OhioLINK, 2012. http://rave.ohiolink.edu/etdc/view?acc_num=akron1333835520.
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Hazlett, Emily G. "Possible Interactions of Serotonin and Oxytocin in the Neural Regulation of Aggressive Behavior." Kent State University Honors College / OhioLINK, 2012. http://rave.ohiolink.edu/etdc/view?acc_num=ksuhonors1335811801.
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Cook, Michelle Elizabeth. "Environmental and social factors influence communications used during crayfish agonistic interactions." Bowling Green, Ohio : Bowling Green State University, 2008. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=bgsu1212431269.
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Clark, Jessica. "The Sensory Mechanisms of Crayfish (Orconectes rusticus) Used in Detecting Predatory Threats." Bowling Green State University / OhioLINK, 2017. http://rave.ohiolink.edu/etdc/view?acc_num=bgsu1490027671892276.
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Reisinger, Ryan Rudolf. "Abundance and predatory impact of killer whales at Marion Island." Diss., University of Pretoria, 2011. http://hdl.handle.net/2263/27643.
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Killer whales are the oceans’ apex predator and are known to have important effects on ecosystems. At Subantarctic Marion Island, southern Indian Ocean, they have only been studied opportunistically, resulting in limited knowledge of their ecosystem impact here. This dissertation describes the prey and seasonal abundance, estimates the population size and assesses the predatory impact of killer whales on seals and penguins at Marion Island, using dedicated and opportunistic shore-based observations and photographic identification, from 2006 to 2009. During 823 sightings of killer whales at Marion Island (2006 to 2009) 48 predation events were recorded; in only 10 cases could prey be identified. Killer whales fed on fur seals, elephant seals and penguins. Constant effort (dedicated) observations (259 hours, 2008 to 2009) showed that killer whale abundance, which peaked in September to December with a secondary peak in April to May, is linked to the abundance of seals and penguins. Mark-recapture analyses were performed using nearly 10 000 photographs taken from 2006 to 2009. Following careful quality control criteria 37 individuals were identified and a population size of 42 (95% CI = 35-50) individuals estimated using the open population POPAN parameterization in the software program MARK. The analytical approach is more rigorous than that used in any previous population size assessment at Marion Island. Finally, the above data were integrated to assess whether top-down control of seal and penguin populations at Marion Island is generally plausible using a simple process of elimination. Based on published data I predicted the energetic ingestion requirements of adult male and female killer whales as 1 394 MJ.day-1 and 1 028 MJ.day-1, respectively. Expanding these requirements to the 37 killer whales photographically identified at Marion Island, the population requires 40 600MJ.day-1. Based on available energy density and mass data, I predicted the energy content of available seal and penguin prey and calculated the rates at which killer whales would consume these prey in various scenarios. Penguins and Subantarctic fur seals are relatively insensitive to killer whale predation owing to their large population sizes (10 000s to 100 000s), conversely, the smaller populations (100s to 1 000s) of Antarctic fur seals and southern elephant seals are sensitive to predation, particularly the latter as they have a high energy content (approximately 2 000 to 9 000 MJ). Populations of these seals are currently increasing or stable and I conclude that presently killer whale predation is not driving population declines, although they clearly have the potential for regulation of these smaller populations. Thus, if population sizes were reduced by bottom-up processes, if killer whale diet shifted, or if prey availability changed, top-down control by killer whales could become significant. This study provides baseline information for the informed management and conservation of killer whales at Marion Island, identifies avenues for further research, and provides a foundation for the continuation of structured and dedicated killer whale research at Marion Island.Dissertation (MSc)--University of Pretoria, 2011.
Zoology and Entomology
unrestricted
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Hill, Jennifer Marie. "Predator biomass and habitat characteristics affect the magnitude of consumptive and non-consumptive effects (NCEs): experiments between blue crabs, mud crabs, and oyster prey." Diss., Georgia Institute of Technology, 2011. http://hdl.handle.net/1853/41172.
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Recent research has focused on the non-lethal effects of predator intimidation and fear, dubbed non-consumptive effects (NCEs), in which prey actively change their behavior and habitat use in response to predator chemical cues. Although NCEs can have large impacts on community structure, many studies have ignored differences in predator population structure and properties of the natural environment that may modify the magnitude and importance of NCEs. Here, I investigated the roles of predator size and density (i.e. biomass), as well as habitat characteristics, on predator risk assessment and the magnitude of consumptive and NCEs using blue crabs, mud crabs, and oyster prey as a model system. Predation experiments between blue crabs and mud crabs demonstrated that blue crabs consume mud crabs; however, the consumptive effects were dependent upon blue crab body size and habitat type. When mud crabs were exposed to chemical cues from differing biomasses of blue crabs in laboratory mesocosms, mud crab activity and predation on oysters was decreased in response to high biomass treatments (i.e. large and multiple small blue crabs), but not to low biomass predators (i.e single small blue crab), suggesting that risk associated with predator size is perceptible via chemical cues and is based on predator biomass. Further experiments showed that the perception of risk and the magnitude of the NCEs were affected by the sensory cues available and the diet of the blue crab predator. The NCE based on blue crab biomass was also demonstrated in the field where water flow can disperse cues necessary for propagating NCEs. Properties of water flow were measured within the experimental design and during the experiment and confirmed cage environments were representative of natural conditions and that patterns in NCEs were not associated with flow characteristics. These results affect species conservation and commercial fisheries management and demonstrate that we cannot successfully predict NCEs without considering predator size structure and the contexts under which we determine predator risk.
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Midthassel, Audun. "Interactions between the predatory mite Amblyseius swirskii and it's factitious prey Suidasia medanensis with implications for field release." Thesis, Imperial College London, 2015. http://hdl.handle.net/10044/1/26986.
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Predatory mites are important components in biological control of arthropod pests in protected crops. The whitefly and thrips predator Amblyseius swirskii (Acari: Phytoseiidae) is an efficient biocontrol agent used widely for pest control in protected vegetable and ornamental crops. Amblyseius swirskii can be mass-reared on at least three species of astigmatid mites but little is known about their predator-prey interactions and population dynamics. These factitious prey allow for large-scale efficient rearing systems and novel crop inoculation methods. The use of breeding sachets offer a predatory mite delivery method with prolonged and sustained crop inoculation. This study endeavoured to assess the suitability of the factitious prey Suidasia medanensis (Acari: Suidasidae) for mass-rearing and field deployment of A. swirskii by studying the life table parameters of the predator on a diet of the said prey. The underlying predator-prey interactions were examined through a series of laboratory experiments focusing on the response of A. swirskii to prey density, preference of prey life stage, capture success ratio and the defence volatiles of adult S. medanensis against predators. Furthermore, in order to understand the behaviour and performance of a breeding sachet the internal population dynamics were studied in relation to release rates from the sachet. These studies were extended to examine the effect of different simulated crop conditions on predator release, focusing on temperature and relative humidity at constant and alternating controlled conditions. In addition to different crop conditions, A. swirskii may be exposed to various other crop protection products in the field as part of an IPM programme. The compatibility of A. swirskii with one such product, the fungal entomopathogen Beauveria bassiana (Balsamo), for concomitant use in the field was investigated through pathogenicity studies and sublethal effects under controlled conditions. Suidasia medanensis was found to be of good nutritional value to A. swirskii resulting in population growth rates similar to target pests, as reported in literature. Specific predator-prey interactions were identified, such as Type II functional response, preference to egg stages of the prey and the defence volatile of S. medanensis, the significance of which are discussed in depth in the thesis. Underlying dispersal strategies and the association between breeding sachet productivity and predator output was established. Furthermore, climatic conditions were found to have significant effects on sachet performance with clear indications of what constitutes favourable and unfavourable conditions. Amblyseius swirskii was found to be a physiological host to B. bassiana. Due to low-to-moderate mortality rates under ideal laboratory conditions, little effect on juvenile mites and no effect on offspring of treated mites these two biocontrol agents were concluded to have good potential for concomitant use, but with further trials required.
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Elkin, Che Miguel. "Effects of habitat complexity and aggressive interactions on predation risk of larval damselflies (Ischnura verticalis)." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1998. http://www.collectionscanada.ca/obj/s4/f2/dsk3/ftp04/mq40887.pdf.
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Simillidou, Aspasia. "Managing emotional labour consequences during aggressive customers' interactions : a study of the Cyprus hospitality industry." Thesis, University of Gloucestershire, 2016. http://eprints.glos.ac.uk/4677/.
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This doctoral investigation explores the area of emotional labour in relation to aggressive customers’ behaviours. In more detail, it is focussing on the way employees engage in emotional labour, which can be done either by surface acting or deep acting, when they are interacting with aggressive customers and the consequences that may arise due to this method. The thematic and narrative literature review conducted by the researcher on the initial stages of this thesis provided the basis and foundations of the creation of the initial conceptual framework on managing the negative consequences of surface acting when interacting with aggressive customers and achieving the desired deep acting during those interactions. The researcher follows the constructivist / interpretivist philosophical approach in her study, and adopts the methodological triangulation for conducting her primary research by using a combination of two qualitative methods, semi-structured interviews and focus groups. The semi-structured interviews were contacted first, and the focus groups, as an additional method, had the purpose of either validating the results or adding to them accordingly. This study revealed that employees are only engaging in surface acting when they are interacting with aggressive customers. This results in a number of negative consequences. The current research has focussed on how to overcome those negative consequences. It further explored the ways that would engage employees in deep acting during those challenging interactions with aggressive customers and the positive effects. The results were presented in the empirically validated conceptual framework that has been created. The findings of this doctoral investigation have contributed both in theory as well as practice. The theoretical contributions include innovative additions to the existing theoretical gaps in the area of emotional labour in terms of how to overcome the negative consequences of surface acting and enhance the use of deep acting during interactions with aggressive customers. Further on, there are also contributions in the literature of the hospitality industry that has been under-researched in regards to this area. In addition, this research is adding to the existing knowledge of how to handle aggressive customers since it is including important findings on how to handle employees’ emotions so that aggressive customers are being treated more effectively. This also benefits the theory of marketing by offering the opportunity for further researchers to use the current empirically tested theoretical framework in order to test the relationship between engaging in deep acting and eliminating customer dissatisfaction. In terms of practical contributions, this research is adding knowledge to the hospitality industry employees, the management and the industry as a whole. While utilising this framework, both management and employees will be able to offer more genuine emotions to their aggressive customers and therefore be able to achieve the best possible results for the organisations they are working for.
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Benedetti, Alison A. "Whatever happens, I'll support you: The effects of autonomy support during aggressive customer service interactions." University of Akron / OhioLINK, 2015. http://rave.ohiolink.edu/etdc/view?acc_num=akron1445334732.
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Martínez-Rivera, Carlos C. "Call timing interactions, aggressive behavior, and the role of acoustic cues in chorus formation in treefrogs." Diss., Columbia, Mo. : University of Missouri-Columbia, 2008. http://hdl.handle.net/10355/5539.
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Thesis (Ph. D.)--University of Missouri-Columbia, 2008.The entire dissertation/thesis text is included in the research.pdf file; the official abstract appears in the short.pdf file (which also appears in the research.pdf); a non-technical general description, or public abstract, appears in the public.pdf file. Title from title screen of research.pdf file (viewed on July 28, 2009) Includes bibliographical references.
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Evans, Matthew Richard. "The role of plumage signals in mate choice and aggressive interactions in male scarlet-tufted malachite sunbirds." Thesis, University of Cambridge, 1991. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.386279.
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O'Brien, David Sean. "The effect of harvesting on size structured predatory and competitive interactions between rainbow trout («Oncorhynchus mykiss») and northern pikeminnow («Ptychocheilus oregonensis»)." Thesis, McGill University, 2009. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=40672.
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A reduction in the consumptive and nonconsumptive effects of predation resulting from harvesting of top predators has been hypothesized to result in failure of harvested species to recover from low abundance, even if harvesting is reduced or ceases. I examined size-structured predatory and competitive interactions between northern pikeminnow (Ptychocheilus oregonensis) and its potential predator rainbow trout (Oncorhynchus mykiss). Specifically, I investigated diel habitat use by northern pikeminnow, the effect of harvesting and community structure on recovery of rainbow trout, and trophic consequences of removing either species. Theoretical predictions were tested with replicated whole-lake manipulations of fish density: adult rainbow trout were removed from two single-species lakes, and from two lakes that also supported northern pikeminnow (two-species lakes), and northern pikeminnow were removed from three two-species lakes. In Chapter 1, I hypothesized that diel horizontal migrations undertaken by northern pikeminnow result from a trade-off between foraging opportunities and predation risk. Although adult rainbow trout removals did not alter northern pikeminnow migratory behaviour, tethering experiments showed that rainbow trout present a risk of predation in pelagic habitats during the day and crepuscular periods. Chapter 2 identified Chaoborus larvae as the most important prey of northern pikeminnow in the pelagic zone. Chaoborus is only available as prey in the pelagic zone at night, and its importance provides evidence that foraging opportunities may reinforce diel horizontal migrations. In Chapter 3, I compared trophic responses to removals of either adult rainbow trout or its potential forage species, northern pikeminnow. While northern pikeminnow removals led to a predicted four-level trophic cascade, the trophic responses to rainbow trout removals were inconsistent among lakes. In Chapter 4 I tested predictions from the cultivation-depensation hypothUne réduction des effets directs et indirects de la prédation suivant la récolte d’un prédateur supérieur peut hypothétiquement empêcher la récupération de ce prédateur, même si la récolte est réduite ou cesse entièrement. J'ai examiné des interactions prédatrices et concurrentielles entre la sauvagesse du nord (Ptychocheilus oregonensis) et son prédateur potentiel, la truite arc-en-ciel (Oncorhynchus mykiss), en relation avec la taille. Spécifiquement, j'ai étudié l'utilisation d'habitat journalier de la sauvagesse du nord, l'effet de la récolte et la structure de la communauté sur le rétablissement de la truite arc-en-ciel, et les conséquences de réduire l’abondance de ces deux espèces sur le réseau trophique. Des prévisions théoriques ont été examinées en manipulant la densité de poissons dans des lacs: les truites arc-en-ciel adultes ont été enlevées de deux lacs qui soutiennent seulement cette espèce (lacs simple-espèce) ainsi que dans deux lacs qui soutiennent également la sauvagesse du nord (lacs deux-espèces). La sauvagesse du nord a aussi été enlevée de trois lacs de type deux-espèces. Au chapitre 1, j'ai postulé que les migrations horizontales journalières entreprises par la sauvagesse du nord résultent d'un compromis entre la recherche de nourriture et le risque de prédation. Bien que les captures intensives des truites arc-en-ciel adultes n’aient pas changé le comportement de migration de la sauvagesse du nord, ces expériences démontrent que la truite arc-en-ciel présente un risque de prédation dans les habitats pélagiques durant le jour et aux périodes crépusculaires. Le chapitre 2 a identifié des larves de Chaoborus comme proie la plus importante de la sauvagesse du nord dans la zone pélagique. Chaoborus est seulement disponible dans la zone pélagique pendant la nuit, et son importance pour la sauvagesse du nord supporte l’hypothèse selon laquelle les migrations horizontales journal
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Anderson, Eric S. "The Response of a Predatory Fish, Ophiodon elongatus, to a Marine Protected Area: Variation in Diet, Catch Rates, and Size Composition." DigitalCommons@CalPoly, 2016. https://digitalcommons.calpoly.edu/theses/1679.
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Marine Protected Areas (MPAs) are a management tool used to protect and sustain many ecologically and economically important fish species from overexploitation by recreational and commercial fishing. Lingcod (Ophiodon elongatus) and some of its prey species, such as rockfish (Sebastes spp.), are species that are protected from fishing in some California MPAs. Lingcod is an apex predator that consumes a variety of fish and invertebrate species. In this study, I sought to assess the effect of an MPA on the abundance, size and diet of Lingcod. I hypothesized that Lingcod in a no-take MPA would be more abundant and larger than Lingcod in an adjacent reference site (REF) that was open to fishing. Furthermore, I hypothesized that diet would differ between Lingcod in caught the MPA and Lingcod in the REF. I collected Lingcod from the Point Buchon State Marine Reserve (MPA) and an adjacent REF site that was open to fishing. I measured, weighed, sexed, and collected stomach contents from Lingcod using the gastric lavage (stomach pumping) technique. Then, I identified prey items from Lingcod stomach contents down to the lowest taxonomic level possible and quantified diet composition by percent by occurrence, percent by number, and percent by mass. Lingcod in the MPA consumed more fish prey items than Lingcod in the REF site. Lingcod in the REF consumed more cephalopod prey items than Lingcod in the MPA. I analyzed the four most common prey items (rockfish, anchovies, flatfish, and octopus) for nutritional content. My data suggest that Lingcod increased in size and abundance in a no-take MPA because they do not suffer from fishing mortality. However, a more nutritious diet could also contribute to a biologically significant advantage for Lingcod in the MPA. To address this would require further research focused on calculating the net energy (gross energy extracted from the prey item minus the energetic costs of handling and digesting the prey item) obtained by Lingcod from consuming different fish and cephalopod prey items. MPAs can be an effective management tool for protecting fish stocks, although, it is important to understand the interspecific interactions between predator and prey species to adaptively mange MPAs and the species that reside within them.
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Renner, Steven C. "An Analysis of Harbor Seal (Phoca Vitulina) and Gray Seal (Halichoerus Grypus) Haul-out Patterns, Behavior Budgets, and Aggressive Interactions on Mount Desert Rock, Maine." Fogler Library, University of Maine, 2005. http://www.library.umaine.edu/theses/pdf/RennerSC2005.pdf.
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Mariana, Frida. "Chip-Calorimetric Monitoring and Biothermodynamic Analysis of Biofilm Growth and Interactions with Chemical and Biological Agents." Doctoral thesis, Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2016. http://nbn-resolving.de/urn:nbn:de:bsz:14-qucosa-191577.
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Over the last years, varieties of technologies for biofilm analysis were developed and established. They work on different principles and deliver information about biofilms on different information levels. In this work, chip-calorimetry was applied as an analytical tool that measures heat produced from biofilms. Any change of metabolism in biofilms is reflected by a changed heat flow. The heat, which is the integral of the heat flow vs. time, is quantitatively related to the growth stoichiometry of the biofilm, as described by the Hess’ Law. The heat flow is related to the growth kinetics with the reaction heat as proportionality factor. The results from the calorimetric measurement thus, deliver general information about growth stoichiometry and kinetics.
The other interpretation of calorimetric results bases on the assumed proportionality between heat flow and oxygen consumption rate (- 460 kJ/mol ). This ratio is called oxycaloric equivalent. Because in case of aerobic growth the majority of oxygen is consumed in catabolic processes during the electron transport phosphorylation, calorimetry is assumed to provide information about the catabolic side of the metabolism.
The newly developed chip-calorimeter applied in this work is much more suitable for biofilm studies compared to conventional microcalorimeters due to the flow-through design of the calorimetric chamber. The measurement of undisturbed growing biofilms and the comparison with conventional biofilm analysis tools (i.e. plate counts, confocal laser scanning microscopy (CLSM), and the determination of intermediates’ concentrations (e.g. ATP)) demonstrate the proper functionality of the calorimetric method and the related cultivation procedure by delivering measurement results in the range of literature values.
However, when the biofilms were challenged with antimicrobial agents i.e. antibiotics, bacteriophage, and predatory bacteria, the calorimetric results surprisingly deviated from the reference analyses. By combining the results of the calorimetric and reference analyses, additional information about the antimicrobial effects on biofilms can be acquired. Combination of heat measurement and plate counts, which is one of the most conventional approaches, demonstrated that antimicrobials (especially the bactericidal acting kanamycin) could cause the loss of culturability while the cells were still metabolically active. The measurement of ATP content resulted in values out of the typical range, which indicated that antimicrobial treatments disturbed the cellular ATP regulation and the ATP concentration was no longer linearly correlated to the cell number. ATP measurements are therefore not suitable for antimicrobial susceptibility testing.
The comparison of heat profiles with the biovolume determined by quantification of microscopic images shows an elevated cell specific heat production rate after the introduction of some antimicrobials (antibiotics and bacteriophage). In case of antibiotics, this can be explained as a consequence of the bacterial defense mechanisms. Most of the described defense mechanisms against antibiotics need biological energy and therefore drive the electron transport phosphorylation (ETP). In case of biofilm treatments with bacteriophage, the trigger of increasing ETP might be the synthesis of phage proteins, hull material, and genetic information molecules. In aerobic conditions, oxygen is used as terminal electron acceptor. Elevated ETP leads therefore to an increase in oxygen consumption, which correlates to the heat production using oxycaloric equivalent as a factor. These correlations explain the increase of cell specific heat productions as biofilms were challenged by antibiotics and bacteriophage. However, also a decrease of specific heat production was observed (in case of predatory bacteria). Here, the predatory bacteria activity caused various damages in host cells, including the interruption of ETP.
With these experiments, chip-calorimetry was demonstrated as a promising complementary tool in biofilm research, which provides deeper insights about metabolic activity and alterations. It benefits from the noninvasive handling and the online, real-time measurement that allow the method to be applied for monitoring purposes. Furthermore, its miniaturized dimension allows easy integration in more complex analytic systems and also reduces experiment costs with minimal media/chemical consumption.
This thesis also demonstrates the potential development of chip-calorimetry to be more suitable for routine analyses. The use of superparamagnetic beads as matrix to grow biofilms allows regulated transfer of biofilm samples into and from the measurement chamber. This was an initial step towards automation and higher-throughput analysis.
One further outcome of the thesis is based on the highly interesting fact about the elevated heat production rate of the host cells induced by the phage infection observed in the chip- calorimetric experiments. The volume specific detection limit of the chip-calorimeter is lower compared to a commercial microcalorimeter. Thus, the infection effect of phages was additionally measured in microcalorimeter to get better quantitative information about the thermal effect of the infection. The results showed that the immediate heat increase after the addition of phage into the solution of the host cells appeared to be quantitatively related to the infection factor, MOI (Multiplicity of Infection).
Unfortunately, microcalorimetric measurements in closed ampoules are often subjected to the oxygen limitation. Thus, this problem of microcalorimetric measurement has been addressed. The combination of experimental results and mathematical modeling showed that the rate of metabolism in the static ampoules is defined by the diffusion rate of oxygen into media. This factor has to be considered while designing biological experiments in closed calorimetric measuring chambers and interpreting the calorimetric results for their biological meaning. Some possible solutions to overcome the oxygen bioavailability problem are e.g. to design the experiments with low biomass, or by using media with elevated density to float the biomass at the interface to air and thus to reduce the diffusion path.
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Galliger, Courtney C. "NAUGHTY OR NICE: SOCIAL INTERACTION ON THE SCHOOL BUS." Connect to this title online, 2006. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=bgsu1148236809.
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Lister, Kelly M. "Aggression and prosocial behavior in adolescents' Internet and face-to-face interactions." Bowling Green, Ohio : Bowling Green State University, 2007. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=bgsu1194123016.
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Russell, Benjamin Gallard School of Biological Earth & Environmental Sciences UNSW. "The role of odour in Australian mammalian predator/prey interactions." Awarded by:University of New South Wales. School of Biological, Earth and Environmental Sciences, 2005. http://handle.unsw.edu.au/1959.4/25144.
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Odour plays an important role in many predator/prey interactions. In the northern hemisphere, many mammalian prey species have been shown to respond to predator odours. It is also widely assumed that mammalian predators utilise odours to locate their prey. This thesis explores the importance of odour in Australian mammalian predator/prey interactions. Responses of native Australian species to the faecal odour of two predators; the native tiger quoll Dasyurus maculatus and the introduced red fox Vulpes vulpes, were evaluated through live-trapping and focussed behavioural studies of captive animals. Tiger quoll responses to prey olfactory cues were investigated in a captive experiment. Native rodents (bush rats Rattus fuscipes, swamp rats R. lutreolus and eastern chestnut mice Pseudomys gracilicaudatus) equally avoided traps scented with either quoll or fox faeces, and in captive experiments, bush rats and swamp rats reduced their average speed in response to both predator odours. Of the marsupial species, northern brown bandicoots Isoodon macrourus and common brushtail possums Trichosurus vulpecula were captured more frequently in quoll-scented traps than unscented traps or foxscented traps, while captures of brown antechinus Antechinus stuarttii, long-nosed bandicoots Perameles nasuta and southern brown bandicoot I. obesulus were unaffected by the either predator odour. In captive experiments, brown antechinus, long-nosed and northern brown bandicoots decreased their foraging in response to both predator odours, and spent less time in areas scented with quoll faeces. Tiger quolls didn't appear to detect odour sources from a distance of >65 cm, but they did follow scent trails and spent more time in areas scented with the urine and faeces of potential prey. Chemical analysis revealed no common components in fox and quoll odour which prey species could be responding to. Therefore, these native species have evolved to respond to fox odour since foxes were introduced to Australia 130 years ago. The stronger response of native rodents to fox odour may be a legacy of their co-evolution with canid predators prior to entering Australia. A better understanding of how odour is utilised in Australian predator/prey interactions may lead to a greater ability to protect Australia's unique mammalian fauna from introduced predators.
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Carvalho, Flaviana Oliveira de. "O cravo brigou com a rosa: afetos e atos agressivos nas interaÃÃes das professoras com as crianÃas em uma prÃ-escola pÃblica." Universidade Federal do CearÃ, 2014. http://www.teses.ufc.br/tde_busca/arquivo.php?codArquivo=12446.
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Conselho Nacional de Desenvolvimento CientÃfico e TecnolÃgicoEste estudo objetivou investigar as interaÃÃes de seis professoras com as crianÃas de quatro e cinco anos de suas turmas, em uma prÃ-escola pÃblica, focalizando os afetos e os atos agressivos docentes que pudessem emergir nesse processo. A fundamentaÃÃo teÃrica consistiu, essencialmente, na abordagem PsicogenÃtica da Pessoa Completa, de Henri Wallon (1981, 1986, 1989). As raras pesquisas relacionadas aos atos agressivos de docentes da EducaÃÃo Infantil fizeram nosso trabalho beber em fontes que pesquisam a relaÃÃo violÃncia e escola. AlÃm dessas perspectivas, contamos com as contribuiÃÃes de estudos contemporÃneos sobre a infÃncia, de diversas Ãreas (histÃria, filosofia, sociologia, psicologia e pedagogia), no intuito de resgatar as transformaÃÃes ou manutenÃÃo de concepÃÃes (crianÃa, infÃncia e EducaÃÃo Infantil) que permeiam a evoluÃÃo do atendimento dedicado Ãs crianÃas pequenas. A metodologia constou de observaÃÃes, apoiadas complementarmente pela Escala de Empenhamento do Adulto, uma entrevista com cada professora e dois grupos focais. As entrevistas individuais versaram sobre aspectos da formaÃÃo e vida profissional das professoras, com aprofundamento para suas concepÃÃes sobre as interaÃÃes que elas estabelecem com as crianÃas. Evidenciou-se que a formaÃÃo inicial das professoras à precÃria e que elas nÃo conseguem precisar os conhecimentos adquiridos que favorecem as interaÃÃes com as crianÃas. As professoras nÃo tÃm muita intimidade com a temÃtica. Os grupos focais pretenderam abarcar as concepÃÃes das professoras sobre atos agressivos, seus afetos e se elas os reconhecem em sua prÃtica cotidiana. As anÃlises mostraram que as professoras atribuem grande valor ao desenvolvimento intelectual das crianÃas, nÃo percebendo suas necessidades afetivas, psicomotoras e sociais. Apontam suas concepÃÃes de crianÃa na prÃ-escola como aluno, prÃ-escola como escola e desenvolvimento como aprender a ler, escrever e contar. SÃo unÃnimes em pensar que as crianÃas nÃo sÃo amadas e educadas por suas famÃlias. O contexto das interaÃÃes abriga um clima de tensÃo, e as professoras enxergam as crianÃas como suas inimigas. Creditam seu adoecimento (estresse, problemas na voz e outros) ao dia a dia com as crianÃas. Apontam atitudes e caracterÃsticas do professor favorÃveis e desfavorÃveis Ãs interaÃÃes com as crianÃas. As Ãltimas devem ser evitadas, muito menos pelo respeito a que as crianÃas tÃm direito, do que pela preocupaÃÃo em nÃo ter conflitos com suas famÃlias. As professoras revelam situaÃÃes nas quais âsaem do sÃrioâ e acabam falando grosserias, gritando, obrigando as crianÃas a fazerem coisas que nÃo desejam e dando puxÃes de braÃo. De modo geral, as professoras sÃo insensÃveis Ãs necessidades das crianÃas, adotam posturas autoritÃrias e centralizadoras, com Ãnfase no disciplinamento e na puniÃÃo do movimento infantil, nÃo conseguindo lidar com situaÃÃes de constante oposiÃÃo, preservaÃÃo de si e seduÃÃo, comportamentos tÃpicos das crianÃas no personalismo. Encontramos interaÃÃes verticalizadas e imperÃcia em relaÃÃo aos conflitos corriqueiros entre as crianÃas e entre as professoras e as crianÃas.
This study aimed at investigating about of the interaction established among six teachers and children aged four and five years old from their classrooms in a public preschool, focusing on their emotions and aggressive acts that teachers could emerge in the process. The theoretical foundation consisted essentially of the psychogenic approach of the Whole person, Henri Wallon (1981, 1986, 1989). The rare queries related to aggressive acts of teachers in kindergarten made our work rely on fountains which research the relationship between violence and school. In addition to these perspectives, we relied on contributions of contemporary studies on children in various areas (history, philosophy, sociology, psychology and pedagogy), in order to rescue the transformation or maintenance of conceptions (child, childhood and Early Childhood Education) which permeate the evolution of the service dedicated to small children. The methodology consisted of observations, supported additionally by the Adult Engagement Scale, an interview with each teacher and two focus groups. The individual interviews were about aspects of graduation and professional lives of the female teachers, getting deeper into their views about of the interactions they have with the children. It was evident that the initial graduation of the teachers is poor and they cannot establish the acquired knowledge which favors the interactions with children. The teachers do not have much familiarity with the subject. The focus groups intended to encompass the conceptions of the teachers about aggressive acts, their affections and if they recognize them in their daily practice. The analyses showed that the teachers attribute greater value to the intellectual development of the children, without perceiving their affective, psychomotor and social needs. They point out their conceptions of child in preschool as a student, preschool as school and development as to learn how to read, write and count. They are unanimous in thinking that the children are not loved and educated by their families. The context of the interactions shelters a climate of tension, and the teachers see the children as their enemies. They believe that their illness (stress, voice problems and others) come from their daily routine with the kids. They point to attitudes and characteristics of the teacher as favorable and unfavorable to the interactions with children. The later should be avoided, much less for the respect thatâs the childrenâs right, than by the concern not to have conflicts with their family. The teachers reveal situations in which "they lose their temper" and end up uttering rudeness, shouting, forcing children to do things they do not want to and tugging their arm. Overall, the teachers are insensitive towards the needs of the children, they adopt authoritarian and centralizing postures with emphasis on discipline and punishment of childâs movement, failing to deal with situations of constant opposition, their own preservation and seduction, typical behaviors of children in personalism. We found verticalized interactions and malpractice in relation to everyday conflicts among children and among teachers and children.
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Warzée, Nathalie. "Prey unpredictability and unfavourable host trees influence the spatial distribution of the polyphagous predator Thanasimus formicarius (L.), Coleoptera :Cleridae." Doctoral thesis, Universite Libre de Bruxelles, 2005. http://hdl.handle.net/2013/ULB-DIPOT:oai:dipot.ulb.ac.be:2013/211012.
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Polyphagy is a very common trait among insects. In this study, we focus on a generalist bark-beetle predator, Thanasimus formicarius (L.) (Coleoptera, Cleridae), which feeds on many scolytids in spruce, pine and broad-leaf stands. It is known to respond to the pheromones of many scolytids, among which the most harmful spruce bark beetle in Europe, Ips typographus (L.). The adults attack scolytid adults and oviposit on attacked trees where their larvae feed upon immature stages of the prey. However, a bottom-up process limits Thanasimus formicarius’ impact on spruce bark beetles, because in most cases the bark of spruce is too thin for sheltering pupal niches and mature larvae have to leave the trees. On pine however, pupation is quite successful and reproductive success is high.
The present work estimates the advantages (complementary prey during gaps among the phenology of pine bark beetles or due to the population fluctuations of most scolytids) and constraints (landing on unsuitable host trees for the predator’s reproduction) for T. formicarius to have a wide range of prey.
Passive barrier-trappings showed that the presence and abundance of scolytid species vary strongly from year to year. So, polyphagy in T. formicarius appears as a response to fluctuating prey supplies.
This way of foraging may lead T. formicarius towards stands not always favourable for its development (for example, spruces).
At the tree level, funnels and pitfall-traps caught high numbers of third-instar T. formicarius larvae walking on the bark surface of standing spruces infested by Ips typographus (respectively 365 and 70 L3s). After feeding into the whole infested part of the trunk, these larvae are obliged to migrate outside of the galleries to favourable pupation site (e.g. the base of the trees where the bark is thicker), or even to leave the trees and search for an acceptable pupation substrate in the litter.
At the landscape level, different trapping experiments showed a correlation between catches of T. formicarius and the proportion of pines around each trap. Consequently, in a metapopulation landscape pattern, pines would act as “sources” of predators, whilst spruces are “sinks”. Indeed, Thanasimus formicarius are trapped in higher numbers in mixed stands comprising pines. This observation is also corroborated in a four-year trapping experiment in the North-East of France, following the storms of December 1999. The predator/prey ratios (T. formicarius/I. typographus) were higher in stands comprising pines than in stands without pines. The first step of a method to estimate Ips typographus infestation trends thanks to the predator/prey ratios was also developed.
Doctorat en sciences, Spécialisation biologie animale
info:eu-repo/semantics/nonPublished
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Brown, Logan Arthur. "Habitat determinants and predatory interactions of the endemic freshwater crayfish (koura, Paranephrops planifrons) in the lower North Island, New Zealand : a thesis presented in partial fulfillment of the requirements for the degree of Masters of Science in Ecology at Massey University, Palmerston North, New Zealand." Massey University, 2009. http://hdl.handle.net/10179/1168.
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A study in the Lower North Island located Parenephrops planifrons (koura) at 73 sites out of 104 sites visited (appendix 1). There was a significant difference in habitat variables between the sites which had koura present and those where they were absent. Examples of sites are shown in Appendix 3. Habitat variables important for classifying koura habitat included riparian cover, predators, winter equilibrium temperature and presence of in-stream habitat in the form of vegetation, litter cover and the stream sequence composition. Regression trees built could accurately describe the data but the kappa statistic was low.
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Tsai, Yi-Hsiu, and 蔡宜修. "Aggressive Interactions between Solenopsis Geminata and Paratrechina Longicornis." Thesis, 2014. http://ndltd.ncl.edu.tw/handle/51149301273720663788.
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碩士靜宜大學
生態人文學系
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Solenopsis geminata introduced into central and southern Taiwan over thirty years. As invasive ant species utilizes a wide variety of food resources and gains a large amount of food, it may reach even higher population densities. In this study, ant species was investigated using pitfall traps and bait traps in the infested sites in Taichung. Results from the pitfall traps showed that 9 species of ants were found and Paratrechina longicornis was more common in the infested areas. P. longicornis was faster in finding food in bait traps. However, S. geminata was considerably faster in recruiting and occupying to food. The inter- and intra-specific aggressive interactions between S. geminata and P. longicornis were investigated in this study. Workers of S. geminata were more likely to behave aggressively than were workers of P. longicornis during the interaction. Comparing the mortality rate of S. geminata and P. longicornis in 24 hours after interspecific individual aggressive interaction, the results showed that while S. geminata played resident or intruder role, the mortality was 66.7% or 64.4%, respectively. On the other hand, the mortality while P. longicornis played resident or intruder role was 84.4% or 77.8%, respectively. In group assays, the mortality of S. geminata and P. longicornis were 44% and 94%, respectively. The result of the study provides a preliminary understanding to S. geminata and P. longicornis habited in the same area as well as the strategies they used when they competed the same resource and habitat. S. geminata is more aggressive and quick in recruiting; P. longicornis, on the contrary, is in evasive manner. Using baiting and interspecific aggressive interaction experiments help to understand the role S. geminata plays in the ecosystem and its influence to other ant species.
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Diaz-Uriarte, Ramón. "Effects of aggressive interactions on antipredator behavior : empirical and theoretical aspects /." 2000. http://www.library.wisc.edu/databases/connect/dissertations.html.
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Revoy, MaryAdele. "Control behaviors exhibited in the marital interactions of aggressive and nonaggressive husbands." 1998. http://catalog.hathitrust.org/api/volumes/oclc/41220100.html.
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Thesis (M.S.)--University of Wisconsin--Madison, 1998.Typescript. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaves 54-66).
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De, Rubeis Sera. "Understanding Treatment Effectiveness for Aggressive Youth: The Importance of Regulation in Parent-child Interactions." Thesis, 2009. http://hdl.handle.net/1807/18082.
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Reviews summarizing hundreds of studies cite Parent Management Training (PMT) and Cognitive-Behaviour Therapy (CBT) as some of the most effective interventions for aggressive youth (e.g., Brestan and Eyberg, 1998). However, variability in outcomes persists, and we have yet to understand why certain interventions only produce behaviour change in some children. Using a clinical sample of 57 children (53 boys, 4 girls) and their mothers enrolled in a combined PMT/CBT program, the current study examined the relation between changes in real-time parent-child interactions, and children’s externalizing outcomes from pre- to post-treatment. Results showed that dyads who were regulated in their interactions over time reported greater reductions in externalizing symptoms from pre- to post-treatment compared to dysregulated dyads. Changes in mean levels of affective content (e.g., negativity) were not associated with aggressive outcomes. Findings suggest that dyadic regulation may be an important process associated with treatment success for aggressive youth.
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Correia, Edna Rita de Freitas da Costa. "Small pelagics, predatory fish and seabirds : trophic and behavioural interactions in a marine protected area in Guinea-Bissau." Doctoral thesis, 2018. http://hdl.handle.net/10451/35914.
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Tese de doutoramento, Biologia e Ecologia das Alterações Globais (Biologia e Ecologia Tropical), Universidade de Lisboa, Faculdade de Ciências, 2018Rapid and significant declines in marine biodiversity, caused by overfishing and global changes, are affecting the functioning of marine ecosystems worldwide. Understanding food-web dynamics is essential for the development of efficient ecosystem management actions. In West Africa, knowledge of food-web dynamics is particularly urgent given that fish stocks are collapsing and fisheries sustain the livelihoods of a significant part of the human population. This thesis addresses the trophic interactions of the marine community of the Bijagós Archipelago, Guinea-Bissau. The extensive mangroves and mudflats of this continental archipelago make it an important area for several migratory species (e.g. marine turtles, waders) and resident species (e.g. seabirds), as well as a nursery area for several fish species. The great biodiversity value of the Bijagós led it to be declared as UNESCO Biosphere Reserve in 1996 and a Ramsar site in 2014. Nevertheless, few studies have been conducted in its marine ecosystem. Seasonal, lunar tidal and diel variations of the coastal small fish community of the Bijagós Archipelago were studied through beach seining along spatial and temporal scales. The diet and foraging behaviour of marine predators (predatory fishes and seabirds) was also studied, with particular interest in their facilitative feeding associations. Traditional methods were used for diet description, such as, the macroscopic identification of prey remains from stomach contents of predatory fish and pellets of breeding seabirds. We also used next-generation sequencing, employing DNA metabarcoding on the identification of prey in the droppings of wintering seabirds. This was the first time this method was used for studying the feeding ecology on migratory birds in their wintering quarters. Additionally, behavioural focal observations of seabirds were performed to investigate their feeding habits. Given the lack of previous descriptive studies, this work also focuses the particularities of length-weight relationships of six fish species. The present study showed that the marine ecosystem of the Bijagós is strongly dominated by a small pelagic fish species, Sardinella maderensis. This species was the most abundant throughout the year as well as in all the islands, and the most frequent item in the diet of all marine predators. In regards to facilitative foraging, different species of seabirds showed distinctive degrees of reliance on associations, ranging from completely independent to near-obligatory. The results also suggest that the use of associations influences the distribution of seabird species and may enhance their foraging success. The overall findings presented here indicate that the marine ecosystem of the Bijagós Archipelago is a wasp-waist type, with Sardinella maderensis as the key small pelagic species, and that an ecosystem-based approach must be considered for the adequate management of the archipelago. Declines in populations of predatory fish and small pelagic fish are both likely to influence the distribution and foraging success of seabirds, with impacts on their survival and breeding success.
A biodiversidade marinha tem sofrido rápidos e significativos declínios, sobretudo devido à sobrepesca e às alterações globais, o que tem afectado o funcionamento dos ecossistemas marinhos por todo o mundo. Conhecer as dinâmicas das redes tróficas é assim essencial para o desenvolvimento de acções eficientes para a gestão dos ecossistemas. Na África Ocidental, este conhecimento é ainda mais urgente, uma vez que muitas populações de stocks pesqueiros estão em colapso e as populações locais dependem grandemente da pesca e do peixe para sobreviver. A presente tese estuda as interacções tróficas da comunidade marinha do Arquipélago dos Bijagós, Guiné-Bissau. Os extensos mangais e zonas de vasa intertidal que este arquipélago continental contém, fazem dele uma área de extrema importância para uma variedade de espécies migradoras (e.g. tartarugas marinhas, aves limícolas), de espécies residentes (e.g. aves marinhas), e também como berçário de várias espécies de peixes. O seu grande valor em termos de biodiversidade levou os Bijagós a serem declarados Reserva Biosfera pela UNESCO em 1996 e sítio Ramsar em 2014. Ainda assim, poucos estudos foram realizados no seu ecossistema marinho. Neste trabalho foram estudadas as variações entre estações, ciclos lunares e ciclos diários na comunidade dos pequenos peixes pelágicos costeiros do Arquipélago dos Bijagós. Para isso foram efectuadas pescas com rede de xávega de modo a cobrir ambas as épocas e em diferentes ilhas. Foi estudada a dieta e comportamento alimentar de predadores marinhos (peixes predadores e aves marinhas), com especial interesse nas associações facilitativas alimentares. Para o estudo da dieta foram usados métodos tradicionais, como a identificação macroscópica de restos de presas presentes nos conteúdos estomacais de peixes predadores ou nas egragópilas de aves marinhas nidificantes. Foram também usados métodos de next-generation sequencing aplicando DNA metabarcoding na identificação de presas nos dejectos de aves marinhas invernantes. Esta foi a primeira vez que este método foi usado para o estudo da dieta de aves marinhas migradoras nos seus locais de invernada. Foram também realizadas observações comportamentais de aves marinhas para o estudo dos seus hábitos alimentares. Devido à falta de estudos da relação comprimento-peso para determinados peixes, esta relação foi calculada para seis espécies. O presente estudo mostrou que o ecossistema marinho dos Bijagós é fortemente dominado por uma espécie de pequeno pelágico, a Sardinella maderensis. Esta espécie foi a mais abundante ao longo do ano e em todas as ilhas. Foi também a espécie mais frequente na dieta de todos os predadores marinhos estudados. Em relação ao comportamento alimentar facilitativo, as diferentes espécies de aves marinhas mostraram distintos graus de dependência destas associações, variando entre completamente independente a quase obrigatória. Os resultados sugerem que o uso de associações influencia a distribuição das aves marinhas e pode aumentar o seu sucesso alimentar. Os resultados globais deste trabalho indicam que o ecossistema marinho do Arquipélago dos Bijagós é do tipo wasp-waist, com a Sardinella maderensis como espécie de pequeno pelágico chave. Assim, para uma conservação eficiente do arquipélago, deve ser considerada uma abordagem de gestão ao nível do ecossistema. Diminuições das populações tanto de peixes predadores como de pequenos pelágicos são igualmente susceptíveis a influenciar a distribuição e sucesso alimentar das aves marinhas, com impacto na sua sobrevivência e sucesso reprodutor.
Fundação para a Ciência e a Tecnologia (FCT), MAVA Foundation, projeto "La recherche participative au service de la conservation de la biodiversité du Parc National Marin de João Vieira-Poilão (Archipel des Bijagós)”
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Reich, Stephanie Michelle. "Do nice guys finish last? the role of prosocial and aggressive behavior in peer interactions /." Diss., 2006. http://etd.library.vanderbilt.edu/ETD-db/available/etd-02252006-115545/.
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Lin, Gongyu. "Are predatory mites efficient dispersal agents of entomopathogenic fungi? : understanding the process of disease transmission from predators to prey for biological control." Thèse, 2019. http://hdl.handle.net/1866/22696.
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Bongard, Cynthia Lee. "Molecular Characterization of Endophytic Fungal Colonizers of Plant Roots: A Comparison between the Aggressive Invasives Vincetoxicum rossicum, Alliaria petiolata, and Local Native Plant Species." Thesis, 2013. http://hdl.handle.net/1807/35779.
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Soil fungi play an important role in regulating plant communities as well as above and below ground ecosystem-level processes; conversely, plant communities may also affect the structure and functionality of these root-associating fungi. Alteration of these fungal communities due to non-native plant invasion has the potential to disrupt biogeochemical cycling, soil structure, and plant growth. Both beneficial symbionts such as arbuscular mycorrhizal fungi (AMF) as well as the total fungal community are potentially altered by aggressive invasive plant species in such a way as to disrupt existing native endophytic fungal communities in the soil post invasion. This disruption could provide a pathway for invasion and suggests the importance of investigating plant-fungal associations in invaded ranges. I used molecular techniques to characterize the fungal communities colonizing Vincetoxicum rossicum or Dog-strangling vine (DSV) and Alliaria petiolata or garlic mustard, both European natives that are currently well established in Eastern North America, as well as native plants that are commonly found persisting in the presence of dense colonies of DSV, as well as those same natives growing separately from DSV. Fungi colonizing different plant groups were analyzed using primers that target the internal transcribed spacer region of the ribosomal operon in order to amplify total fungal species (TF), as well as primers designed to exclusively amplify AMF using small subunit rRNA sequences. Significant differences were observed in the diversity of both the TF and the AMF communities colonizing native plants in the invaded sites relative to the uninvaded sites. Sequencing work indicated that DSV forms associations with a broad array of fungal partners relative to proximal native plants, suggesting the likelihood of it being a fungal generalist. As well, DSV was found to associate with described opportunistic AMF such as Glomus intraradices, G. caledonium, G. fasciculatum and G. mosseae, while natives growing within DSV patches were not. Finally, garlic mustard was found to have the dominant effect where DSV and garlic mustard were co-occurring. These findings support the ongoing investigations into plant invasion processes, and therefore contribute to the development of effective strategies for invasive species management as well as site restoration techniques.
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Mariana, Frida. "Chip-Calorimetric Monitoring and Biothermodynamic Analysis of Biofilm Growth and Interactions with Chemical and Biological Agents." Doctoral thesis, 2014. https://tud.qucosa.de/id/qucosa%3A29133.
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Over the last years, varieties of technologies for biofilm analysis were developed and established. They work on different principles and deliver information about biofilms on different information levels. In this work, chip-calorimetry was applied as an analytical tool that measures heat produced from biofilms. Any change of metabolism in biofilms is reflected by a changed heat flow. The heat, which is the integral of the heat flow vs. time, is quantitatively related to the growth stoichiometry of the biofilm, as described by the Hess’ Law. The heat flow is related to the growth kinetics with the reaction heat as proportionality factor. The results from the calorimetric measurement thus, deliver general information about growth stoichiometry and kinetics.
The other interpretation of calorimetric results bases on the assumed proportionality between heat flow and oxygen consumption rate (- 460 kJ/mol ). This ratio is called oxycaloric equivalent. Because in case of aerobic growth the majority of oxygen is consumed in catabolic processes during the electron transport phosphorylation, calorimetry is assumed to provide information about the catabolic side of the metabolism.
The newly developed chip-calorimeter applied in this work is much more suitable for biofilm studies compared to conventional microcalorimeters due to the flow-through design of the calorimetric chamber. The measurement of undisturbed growing biofilms and the comparison with conventional biofilm analysis tools (i.e. plate counts, confocal laser scanning microscopy (CLSM), and the determination of intermediates’ concentrations (e.g. ATP)) demonstrate the proper functionality of the calorimetric method and the related cultivation procedure by delivering measurement results in the range of literature values.
However, when the biofilms were challenged with antimicrobial agents i.e. antibiotics, bacteriophage, and predatory bacteria, the calorimetric results surprisingly deviated from the reference analyses. By combining the results of the calorimetric and reference analyses, additional information about the antimicrobial effects on biofilms can be acquired. Combination of heat measurement and plate counts, which is one of the most conventional approaches, demonstrated that antimicrobials (especially the bactericidal acting kanamycin) could cause the loss of culturability while the cells were still metabolically active. The measurement of ATP content resulted in values out of the typical range, which indicated that antimicrobial treatments disturbed the cellular ATP regulation and the ATP concentration was no longer linearly correlated to the cell number. ATP measurements are therefore not suitable for antimicrobial susceptibility testing.
The comparison of heat profiles with the biovolume determined by quantification of microscopic images shows an elevated cell specific heat production rate after the introduction of some antimicrobials (antibiotics and bacteriophage). In case of antibiotics, this can be explained as a consequence of the bacterial defense mechanisms. Most of the described defense mechanisms against antibiotics need biological energy and therefore drive the electron transport phosphorylation (ETP). In case of biofilm treatments with bacteriophage, the trigger of increasing ETP might be the synthesis of phage proteins, hull material, and genetic information molecules. In aerobic conditions, oxygen is used as terminal electron acceptor. Elevated ETP leads therefore to an increase in oxygen consumption, which correlates to the heat production using oxycaloric equivalent as a factor. These correlations explain the increase of cell specific heat productions as biofilms were challenged by antibiotics and bacteriophage. However, also a decrease of specific heat production was observed (in case of predatory bacteria). Here, the predatory bacteria activity caused various damages in host cells, including the interruption of ETP.
With these experiments, chip-calorimetry was demonstrated as a promising complementary tool in biofilm research, which provides deeper insights about metabolic activity and alterations. It benefits from the noninvasive handling and the online, real-time measurement that allow the method to be applied for monitoring purposes. Furthermore, its miniaturized dimension allows easy integration in more complex analytic systems and also reduces experiment costs with minimal media/chemical consumption.
This thesis also demonstrates the potential development of chip-calorimetry to be more suitable for routine analyses. The use of superparamagnetic beads as matrix to grow biofilms allows regulated transfer of biofilm samples into and from the measurement chamber. This was an initial step towards automation and higher-throughput analysis.
One further outcome of the thesis is based on the highly interesting fact about the elevated heat production rate of the host cells induced by the phage infection observed in the chip- calorimetric experiments. The volume specific detection limit of the chip-calorimeter is lower compared to a commercial microcalorimeter. Thus, the infection effect of phages was additionally measured in microcalorimeter to get better quantitative information about the thermal effect of the infection. The results showed that the immediate heat increase after the addition of phage into the solution of the host cells appeared to be quantitatively related to the infection factor, MOI (Multiplicity of Infection).
Unfortunately, microcalorimetric measurements in closed ampoules are often subjected to the oxygen limitation. Thus, this problem of microcalorimetric measurement has been addressed. The combination of experimental results and mathematical modeling showed that the rate of metabolism in the static ampoules is defined by the diffusion rate of oxygen into media. This factor has to be considered while designing biological experiments in closed calorimetric measuring chambers and interpreting the calorimetric results for their biological meaning. Some possible solutions to overcome the oxygen bioavailability problem are e.g. to design the experiments with low biomass, or by using media with elevated density to float the biomass at the interface to air and thus to reduce the diffusion path.
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KOPAČKA, Michal. "Interakce mezi organismy obývajícími jírovec maďal (Aesculus hippocastanum)." Doctoral thesis, 2018. http://www.nusl.cz/ntk/nusl-375691.
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Ph.D. thesis is focused on the study of ecology and interactions among fungal disease horse chestnut leaf blotch, Guignardia aesculi, invasive pest horse chestnut leaf miner, Cameraria ohridella, and predatory mites of family Phytoseiidae. Ph.D. thesis consists of two main parts: 1) a detailed background research, and 2) six separate original published papers or manuscripts describing results of my own studies. The first study investigated spatial distribution of the first generation of C. ohridella in the urban environment in relation to the pest, the mortality of overwintering pupae at the end of vegetation season and the number of hatched C. ohridella and its parasitoids at the beginning of the following vegetation season. The second paper describes the interaction between C. ohridella and G. aesculi during vegetation season. The third and fourth papers deal with the effect of specific microctimatic conditions in site on the damage inflicted to horse chestnut leaves by G. aesculi. In addition, spatial distribution of G. aesculi in urban environment was studied. The fifth paper compared the species composition and the population density of Phytoseiidae between the Czech Republic and Greece. The sixth study described the species composition, abundance, population dynamics and sex ratio of phytoseiid mites inhabiting horse chestnut. The study also investigated, whether the abundance of predatory mites on horse chestnut leaves can be influenced by leaf damage caused by the horse chestnut leaf miner or G. aesculi during vegetation season.
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Maas, Bea. "Birds, bats and arthropods in tropical agroforestry landscapes: Functional diversity, multitrophic interactions and crop yield." Doctoral thesis, 2013. http://hdl.handle.net/11858/00-1735-0000-0022-5E77-5.
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