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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
91

Language Learning without the Feeling of Predatory Monetization using Flat Design : Gamification of Language Learning

Svensson, Kristian January 2022 (has links)
This paper aims to explore how different design choicesaffect players perceived feelings of purposeful limitations andpredatory monetization in educational gamified software. Thisstudy, along with two others, is part of an initiative by the EUto explore teaching of a second language, in this case Russian,through gamification. Using Design Science it is the goal of thiscase study to determine whether it is possible to teach Russianwith the help of gamified software, with a progression model thatdoes not invoke feelings of predatory monetization game conceptsas seen in similar software on the market.
92

Dravý hmyz a roztoči - faktografická informační databáze a výukový systém / Predatory insects and mites - information database and e-learning system

KROČÁKOVÁ, Jana January 2010 (has links)
Aim of thesis was to create an electronic version of an information database and the e-learning system, focusing on predatory insects and mites. The e-learning system provides information about the main types of predatory insects and mites used in biological plant protection, including the types of naturally occurring entomofauna and acarifauna agroecosystems in the Czech Republic. The system contains information about the taxonomy, morphology, development cycles, prey, methods of control, etc. Thesis is a combination of text, tables, photographs and line drawings from professional publications. The various components of the system are interconnected through hyperlinks. The system includes information on the ecotoxicology, dictionary terms and the ability to search based on various criteria. In the photo gallery you can find together 310 images, which are intended to create a picture of the morphology, development cycles and behavior of individual organisms.
93

Understanding the role of Stylochus ellipticus as a predator of Crassostrea virginica in Chesapeake Bay tributaries

Barker, Marion Kensey 05 May 2014 (has links)
Predation may be a key component of the unsuccessful restoration of the Eastern Oyster (Crassostrea virginica), a former keystone species in Chesapeake Bay. Here, I examine the polyclad flatworm Stylochus ellipticus and its potential role as an important predator of C. virginica. Using small-fragment size C. virginica specific DNA primers, oyster DNA was successfully detected in whole organisms homogenates of wild-caught S. ellipticus individuals. Of the 1,575 individuals tested, 68.1% tested positive, thus predation occurred. Predation did not appear to be affected by salinity or temperature; however, season did appear to have an effect on both predation and S. ellipticus abundance (p-value: <0.05). The findings also imply that S. ellipticus are highly mobile, entering the water column to reach hard substrate at various depths, whereas previous studies suggest otherwise. These findings are useful in the planning and management of oyster cultivation and restoration. Furthermore, this study outlines a method of diet study that may be more sensitive than traditional DNA-based techniques.
94

Papel dos receptores opióides m e k da substância cinzenta periaquedutal (PAG) na seleção comportamental durante a lactação. / Role of periaqueductal gray m and k opioid receptors in behavioral selection during lactation.

Klein, Marianne Orlandini 20 April 2012 (has links)
Após o parto, a mãe deve optar por buscar por comida ou cuidar da prole sendo que a substância cinzenta periaquedutal (PAG) é uma área central importante de regulação, seleção e um sítio de ação de opióides. Ainda não se sabe a importância funcional de cada um dos receptores opióides na PAG sobre a expressão dos comportamentos materno e predatório. Foram utilizadas ratas com cânula unilateral implantada na PAG e divididas em dois experimentos: Experimento 1, onde as ratas receberam injeções de agonista m, ou o agonista k, ou sulfato de morfina, ou veículo; Experimento 2, onde receberam antagonista m seguido de sulfato de morfina, ou antagonista k seguido de sulfato de morfina, ou sulfato de morfina, ou veículo. Os animais foram avaliados no teste de comportamento materno versus predatório. Os resultados sugerem que o tônus opióide endógeno é importante para a expressão do comportamento predatório e há possibilidade da morfina agir em mais de um tipo de receptor opióide simultaneamente para promover a inibição do comportamento materno nesse contexto. / After giving birth, a mother must both provide subsistence and care for her young. Periaqueductal gray (PAG) is an important area for behavioral selection and a site of opioid action. The functional role of PAG opioid receptors in the expression of maternal and predatory behaviors is not clear. Rats with unilateral guide cannulae implanted in the PAG were separated into two experiments: Experiment 1 where the animals received injectios of m receptor agonist, or k receptor agonist, or morphine sulfate, or vehicle; Experiment 2, where they received m receptor antagonist followed by morphine sulfate, or k receptor antagonist before morphine sulfate, or morphine sulfate, or vehicle. The animals were then tested for maternal behavior vs. predatory hunting. The results suggest that endogenous opioid tone is important for the expression of predatory behavior. The results further raise the possibility that morphine acts at more than one type of opioid receptor simultaneously to inhibit maternal behavior in this context.
95

Evolução da memória em aranhas do grupo Orbiculariae / Evolution of memory in Orbiculariae spiders

Penna-Gonçalves, Vanessa 01 April 2011 (has links)
A memória é considerada por muitos pesquisadores como um dos produtos mais fascinantes da evolução biológica, justamente por proporcionar aos animais a vantagem adaptativa de se utilizar de uma experiência prévia para a solução de problemas necessários para a sobrevivência. Os animais se utilizam de processos mnemônicos durante o forrageamento, a seleção de parceiros sexuais, seleção de habitat e a preferência alimentar. As aranhas são um modelo interessante em estudos de memória e há evidências do uso de experiências passadas na otimização do forrageio: a teia permite que as aranhas capturem e armazenem mais de um item alimentar. Há carência na literatura de estudos comparativos evolutivos da memória, o que dificulta identificar as possíveis pressões seletivas. O primeiro objetivo deste trabalho foi fazer um estudo comparativo de aspectos da memória predatória em aranhas do grupo Orbiculariae. Este grupo é monofilético e tem como principal sinapomorfia a construção de teia orbicular. Porém, ao longo da evolução, o padrão de teia foi se modificando desde uma estrutura plana até uma tridimensional. Tais modificações podem ter gerado diferenças comportamentais e no sistema de memória dessas aranhas. Por este motivo, o outro objetivo, foi traçar a evolução da memória dentro do grupo. Delinearam-se três grupos de estudo com sete espécies. Na condição natural, observou-se a captura de duas presas sucessivas. Na condição experimental I, ofereceu-se uma primeira presa (p1) à aranha e, em seguida, ofereceu-se uma segunda (p2); durante o deslocamento da aranha até p2, retirou-se p1 da teia. Na condição II, ao invés de se oferecer p2, a aranha foi atraída à periferia (simulando a queda de p2). No deslocamento da aranha até a fonte de vibração removeu-se p1. O indício de memória é observado quando, na supressão da presa, a aranha executa um comportamento denominado Busca. Neste, a aranha executa sacudidas/detecções dos fios no centro/refúgio da teia. A busca por p1 roubada foi observada em todas as espécies estudadas, exceto em Z. geniculata no grupo I. A presença de p2 parece interferir na expressão da memória de p1; deixar p2 na teia enquanto busca por p1, aumenta as chances de p2 também ser roubada por ação dos cleptoparasitas. Zosis apresenta algumas peculiaridades, entre elas a ausência de veneno. Dessa forma, o tempo gasto durante a imobilização de p2 parece ser suficiente para causar o esquecimento de p1. Todas as espécies buscaram por p1 quando não houve oferta de p2, inclusive Zosis. O tempo de busca, na condição I, diminui da base de Araneoidea até as famílias mais derivadas. No grupo II, há uma aparente inversão do sinal filogenético e o tempo de busca aumenta na família mais derivada. A estrutura da teia tridimensional parece ser mais complexa e, por este motivo, exigiria um sistema de navegação espacial também mais complexo quando comparado às aranhas orbitelas. A construção da teia parece ter sido crucial para a captura e armazenamento de presas excedentes, e tal comportamento, juntamente com a diversificação das teias, favoreceu a variação e evolução da memória na Ordem Araneae / Memory is one of the most fascinating products of biological evolution, because it endows animals with the adaptive use a prior experiences to solve survival problems. Animals use mnemonic processes during foraging, selection of sexual partners, habitat selection, and feeding preference. Spiders are an interesting model for studies of memory, and there is evidence of their using of past experiences in optimizing foraging: the web allows the spiders to capture and store more than one food item. In literature, there are few comparative studies, and no one about the evolution of memory, making it difficult to identify the possible selective pressures on memory. The first objective here was to make a comparative study on the aspects of predatory memory in spiders of the group Orbiculariae. This group is monophyletic and its main synapomorphy is building an orbicular web. However, during evolution, the web pattern changed from a flat to a three-dimensional structure. Such changes may have caused differences in behavior and memory. For that reason, another goal was to trace the evolution of memory within the group. We used three experimental groups with seven species each. In natural conditions, there was an observation of the capture of two successive preys. In the experimental condition I, a first prey (p1) was offered to the spider and, subsequently, another prey (p2) was offered; during the locomotion of the spider towards p2, p1 was removed from the web. In condition II, instead of offering p2, the spider was attracted to the periphery (simulating the fall of p2). As the spider moved towards the source of vibration, p1 was removed. The evidence of memory is observed when, in the suppression of the prey, the spider performs a behavior called search behavior: the spider runs plucking on threads in the web hub/retreat. The search for stolen p1 was observed in all species studied, except for Zosis geniculata in group I. The presence of p2 appears to interfere with the expression of p1 memory, and also leaving p2 on the web while searching for p1, increases the chances of having p2 stolen by the action of kleptoparasites. Zosis presents some peculiarities, including the absence of poison glands, leading to a prolonged immobilization of p2, in a time lag that could then be sufficient forget p1. All species sought by p1 when there was no offer of p2, including Zosis. The search time, in condition I, decreases from the base of Araneoidea until the most derived families. In group II, there is an apparent reversal of the phylogenetic signal and the search time increases in the most derived family. The three-dimensional structure of the derived webs seems to be more complex and, therefore, it would require a spatial navigation system also more complex if compared to the flat orbweb. The construction of the web seems to have been crucial for prey capture and storage of surpluses, and such behavior, along with the diversification of the webs, favored the variation and evolution of memory in the Order Araneae
96

Nutrition and habitat driven foraging of wild dolphins in the Bahamas: a recipe for prey

Unknown Date (has links)
Two sympatric dolphin species, Stenella frontalis and Tursiops truncatus, resident to Little Bahama Bank, Bahamas were found to mostly forage independent of one another, but occasionally foraged in mixed groups. Analysis of over 20 years of data revealed the degree of overlap to be minimal with spatially distinct regions identified for both species, environmental segregation based on depth, bottom type, temperature, and time of day. Results based on observational data indicated significant differences in group size and selected prey. For S. frontalis, lactating females had the most distinct diet, which differed from that of non-reproductively active (NRA) females. Pregnant females had ambiguous prey use results, but diet differences were revealed through nutritional analysis. Lactating females had a higher intake of all nutrients (% moisture, % lipid, % protein, and calories) than pregnant females but lower than NRA females. Mother and calf pairs selected prey for caloric and moisture values. The influence of calves on foraging groups was reflected through discrete differences in all nutrients. Males and females appeared to select the same major prey, but female prey use was much more diverse. / by Christopher R. Malinowski. / Thesis (M.S.)--Florida Atlantic University, 2011. / Includes bibliography. / Electronic reproduction. Boca Raton, Fla., 2011. Mode of access: World Wide Web.
97

Aggressive Behaviors Of Adult Male Atlantic Spotted Dolphins (Stenella frontalis) During Intraspecific And Interspecific Aggressive Interactions

Unknown Date (has links)
Atlantic spotted dolphins (Stenella frontalis) and bottlenose dolphins (Tursiops truncatus) are two sympatric species resident to the Bahamas. The visibility of the Bahamian water provided a unique opportunity to study spotted dolphin communication during aggression. This study’s main focus was to decipher any similarities or differences in the behaviors used by spotted dolphins during interspecific and intraspecific aggression. Both similarities and differences were discovered. Biting, following, and chasing behavioral events were used more during interspecific aggression, while the display behavioral class was used more than the contact behavioral class during intrabut not interspecific aggression. This study showed that spotted dolphins use more energy intensive and risky behaviors when fighting interspecifically. This could result from having to fight and defend females from a larger species, trying to avoid sexual harassment from bottlenose males, or needing to use behaviors that are more overt and easily understood during interspecies communication. / Includes bibliography. / Thesis (M.S.)--Florida Atlantic University, 2016. / FAU Electronic Theses and Dissertations Collection
98

Exploration of potential agents for the biological control of the red palm mite, Raoiella indica Hirst (Acari: Tenuipalpidae), on coconut palms in Brazil / Exploração de agentes potenciais para o controle biológico do ácaro-vermelho-das-palmeiras, Raoiella indica Hirst (Acari: Tenuipalpidae), em coqueiros no Brasil

Oliveira, Daniel Chiaradia 17 March 2015 (has links)
The red palm mite, Raoiella indica Hirst (Acari: Tenuipalpidae), has been considered an important pest on coconut palm (Cocos nucifera L.) in the New World. Several studies have been conducted to understand the ecology of this mite, aiming at its control. The search for effective natural enemies to control R. indica has been considered a priority to reduce its importance in areas where it has been newly reported, with special attention to predatory mites of the family Phytoseiidae. Little has been published about the phytoseiid fauna of Thailand, where R. indica has been found at low population levels, perhaps due to the action of natural enemies. The general objective of this thesis was to select promising predatory mites in Thailand (Bangkok and Kamphaeng Saen) to control R. indica on coconut palms in Brazil, to introduce them and to conduct an initial evaluation of their efficiency. Initially, a list of the phytoseiid mites until then reported from Thailand and a taxonomic key to help in their separation were prepared. Thirty two phytoseiid species were known from Thailand before this study; seven new records were presented. The predatory mite fauna associated with R. indica in the central region of Thailand and their population dynamics were assessed. Phytoseiidae was the predatory family most frequently found on coconut and lady palm, Rhapis excelsa (Thunb.) A. Henry, although at low levels (maximum of 0.003 specimens/ cm2 on coconut and 0.008 specimens/ cm2 on lady palm). Amblyseius largoensis (Muma) was the most abundant predator in both sites and on both hosts, except on coconut in Bangkok, which the most abundant was Euseius nicholsi (Ehara & Lee). The levels of R. indica were very low (maximum of 0.03 specimens/ cm2 on coconut and 0.48 specimens/ cm2 on lady palm), compared to what have been reported in other parts of the world. The direct effect of rainfall on the population of R. indica on coconut seedlings in Thailand was evaluated. The results suggested that rainfall reduces considerably the population of R. indica, mainly when the accumulated precipitation in 15 days was over 100 mm. A new mite genus and species of Blattisociidae collected on coconut flowers in Thailand were described. The performances of two predatory mite populations introduced from Thailand, a population previously introduced from La Reunion and a population native from Roraima, Brazil, were compared in relation to their effect on the population of R. indica. The efficiency of the predators could not be demonstrated on coconut seedlings, contrasting with what would be expected from their observed behavior in the laboratory. This result could be due to the overexposure of the predators to sunlight on the leaf surface because of the architecture of the seedlings, probably stimulating them to move to more protected microhabitats. On adult coconut plants, in which the abaxial leaf surface is less exposed, the evaluated predators could have a better performance. Further efforts should be dedicated to evaluate this hypothesis. / O ácaro-vermelho-das-palmeiras, Raoiella indica Hirst (Acari: Tenuipalpidae), tem sido considerado uma importante praga em coqueiro (Cocos nucifera L.) no Novo Mundo. Vários estudos têm sido conduzidos para entender a ecologia deste ácaro, visando ao seu controle. A busca de inimigos naturais eficazes para controlar R. indica tem sido considerada uma prioridade para reduzir a sua importância em áreas em áreas em que tem sido recentemente encontrado, com atenção especial aos ácaros predadores da família Phytoseiidae. Pouco tem sido publicado sobre a fauna de fitoseídeos da Tailândia, onde R. indica tem sido encontrado em baixos níveis populacionais, talvez devido à ação de inimigos naturais. O objetivo geral desta tese foi selecionar ácaros predadores promissores na Tailândia (Bangkok e Kamphaeng Saen) para o controle de R. indica em coqueiros no Brasil, introduzi-los e realizar uma avaliação inicial de sua eficiência. Inicialmente, uma lista dos fitoseídeos até então relatados da Tailândia e uma chave taxonômica para ajudar na sua separação foram elaboradas. Trinta e duas espécies de fitoseídeos eram conhecidas da Tailândia antes deste estudo; sete novos registros foram apresentados. Os ácaros predadores associados a R. indica na região central da Tailândia e sua dinâmica populacional foram avaliadas. Phytoseiidae foi a família de predadores mais freqüentemente encontrada em coqueiro e palmeira ráfia [Rhapis excelsa (Thunb.) A. Henry], embora os seus níveis sejam baixos (máximo de 0.003 espécimes/ cm2 em coqueiro e 0.008 espécimes/ cm2 em palmeira ráfia). Amblyseius largoensis (Muma) foi o predador mais abundante em ambos os locais e em ambos hospedeiros, exceto no coqueiro em Bangkok, em que o mais abundante foi Euseius nicholsi (Ehara & Lee). Os níveis de R. indica foram muito baixos (máximo de 0.03 espécimes/ cm2 em coqueiro e 0.48espécimes/ cm2 em palmeira ráfia), em comparação com o que tem sido relatado para outras partes do mundo. O efeito direto da chuva sobre a população de R. indica foi avaliado em mudas de coqueiro na Tailândia. Os resultados sugeriram que a chuva reduz consideravelmente a população de R. indica, principalmente quando a precipitação acumulada em 15 dias foi superior a 100 mm. Um novo gênero e espécie de ácaro da família Blattisociidae coletada em flores de coqueiro na Tailândia foram descritos. Os desempenhos de duas populações de ácaros predadores introduzidos da Tailândia, uma população previamente introduzida de La Reunion e uma população nativa de Roraima, Brasil, foram comparados em relação a seus efeitos sobre a população de R.indica. Não foi demonstrada a eficiência dos predadores em mudas de coqueiro, contrastando com o que era esperado a partir dos comportamentos observados no laboratório. Este resultado poderia ser devido à exposição excessiva dos predadores à luz do sol na superfície das folhas, por causa da arquitetura das mudas, provavelmente estimulando-os a se locomover para microambientes mais protegidos. Em coqueiros adultos, em que a superfície abaxial da folha é menos exposta, os predadores avaliados poderiam ter melhor desempenho. Esforços adicionais deveriam ser dedicados para avaliar esta hipótese.
99

Piktnaudžiavimo dominuojančia padėtimi, pasireiškiančio nesąžiningų kainų nustatymu esmė ir ypatumai: grobuoniškos kainodaros problema / The essence and peculiarities of abuse of dominant position by establishing unfair prices: the problem of predatory pricing

Kačerauskas, Karolis 02 January 2007 (has links)
The abuse of dominant position by establishing predatory pricing raises when the undertaking, seeking to eliminate its competitor determines to sell goods for unreasonably low price, while after elimination or weakening of competition subsequently raises those prices in order to recoup losses and earn higher profits. In theory there is consensus that determination of such pricing must be based of two-tier tests, which are comprised of price-cost comparison and analysis of subjective intent. Such test has been determined in AKZO case and until recently is applicable in the EC and Lithuanian competition law. It states that the price below VKS is presumed to be predatory; in such case if the price is between VKS and VVS, it can be acknowledged to be predatory if it is used in order to eliminate the competitor. While evaluating this test, the paper discusses practical problems arising while applying VKS criterion and raises proposal to change it by more accurate VIS criterion. Moreover, paper raises the idea that dominant element in AKZO test is not economical elements, but subjective predatory intent. Therefore economical elements must be treated only as a tool, providing the possibility to disclose the content of subjective intent. While analyzing the rules for determination of predatory pricing, the paper also discusses the third criterion which settled in EC practice and maintains the possibility to determine predatory pricing even if the prices are above VVS. After critical... [to full text]
100

Monitoring invazního raka pruhovaného v ÚN Lipno a evaluace jeho predace vybranými druhy ryb / Monitoring of invasive spiny-cheek crayfish in Lipno dam and the evaluation of its predation on chosen fish species.

SALON, František January 2015 (has links)
Astacologic survey took place in ÚN Lipno and was conducted in time from 2012 till 2013. For the actual mapping of the occurrence of spiny-cheek crayfish, the locations of total 17 places were detected. These monitoring areas were carried out in two ways for collecting the samples. The trapping of all individuals was achieved with special instruments, like pots or traps by hands or with the help of nets. For the caught specimens of spiny-cheek crayfish, which were determined by sex, the length of carapace was measured and as well if possible, the postorbital carapace length was taken. Throughout the whole monitoring, 228 individuals of spiny-cheek crayfish were caught in the amount of 107 (47%) females (CL = 21.5 ? 7.3 mm) and 121 (53%) males (CL = 20.1 ? 5 mm). Another aim of this work was to demonstrate that crayfish figure in fish food menu. Catches of fish were carried out in two ways, using fishing rods or into the clutches. The stomachs and intestines contents were analyzed at caught fish samples. If the condition of the contents of stomachs or intestines were allowed, it was also identified, what kind of food it was. For our annual issues, were included mainly species of piscivor fish. Spiny-cheek crayfish were identified in the stomachs of two species of fish, namely perch and pike.

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