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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.
1

Control Design for an Inertially Stabilized Rifle

White, Alejandro Porter 08 January 2008 (has links)
An alternate method for mitigating the depredating physiological affects of a soldiers marksmanship due to combat stressors can be achieved through the design and implementation of a active stabilization system for small arms weapons. The INSTAR system is an innovative active stabilization system designed to decouple the shooter's disturbance effects from the barrel movement. The INSTAR system uses an piezoelectric actuator separating the barrel of the rifle from its stock to stabilize barrel movement. This paper uses various control techniques to develop control algorithms for simulation. The level of performance for each control algorithm is based on how well each they measure up to the criteria developed from the INSTAR system. This paper furthers research on INSTAR by developing and comparing four control designs that may be implemented within the INSTAR system. / Master of Science
2

Differences in the growth of the wolf spider Hogna helluo (Araneae: Lycosidae) reared under high and low food quantity diets

Balfour, Robert Andrew 05 March 2004 (has links)
No description available.
3

Effect of plant traits on host selection and performance of rape stem weevil (Ceutorhynchus napi Gyll.) (Col.: Curculionidae) on resynthesized lines and cultivars of oilseed rape (Brassica napus L.)

Schäfer-Kösterke, Heike Lena 24 July 2014 (has links)
No description available.
4

Aspectos biológicos de Euchroma gigantea (Linnaeus, 1758) (Coleoptera: Buprestidae) em Pachira aquática Aubl. (1775) (Bombacaceae) / Biological aspects of the Euchroma gigantean (Linnaeus, 1758) (Coleoptera: Buprestidae) in Pachira aquatic Aubl. (Bombacaceae)

Fonseca, Ana Paula Pereira da 22 February 2010 (has links)
Pachira aquatica Aubl. (Bombacaceae) (false-cocoa) is a tree which has been broadly used for urban arborization. In some regions of Brazil this tree is found to be infested by Euchroma gigantea (Linnaeus, 1758) (Buprestidae: Coleoptera) whose larval xylophagous habit can cause damages that may bring the fall of P. aquática trees. Considering that in three cities located on the Southeast and Central-West of Brazil, such as: São Paulo, Brasília and Goiânia), were registered serious problems related to infestation of P. aquática by E. gigantea and also because of the difficulties to conduct research using xylophagous insects, the present study was carried out to determine the duration of larval instars, to estimate adult longevity and also to find out the ratio and the sexual proportion of adults colected in the field. Insects were collected on the campus of the Universidade Federal de Alagoas (UFAL), located in the city of Maceió, Alagoas from trees which showed the infestation signals of E. gigantea and conducted to the Laboratório de Entomologia of the Natural History Museum of UFAL, where they were reared on glass cages to obtain the mass of eggs which were then placed on Petri dishes. As soon as the larvae eclose, they were fed on an artificial diet formely prepared to Diatraea flavipennella Box, 1931 (Lepidoptera: Crambidae) and pieces of P. aquática branches. The date of ecdises and death of larvae was registered. The exuviae were kept for posterior measurement of the mesothorax and cephalic capsules. The eggs showed a brownish coloration was found to be deposited in a grouped form. Descendent of adults from the second collection time (February 2009) showed the following characteristics: incubation mean period of 22, 6 (±0,22) days; mean duration of larval period from 1st to 3th instars (17, 69±0,57), (32, 46±2,75) and (41,00±3,85) days, respectively, sexual ratio of collected adults: 0,31; longevity mean of (52,5±6,07); ratio and sexual proportion of 0,2 and 1 female: 4 males. Descendent of adults from the fourth collection time (May 2009) showed the following characteristics: embrionary period: 24,70 (±0,25) days; duration of larval period from 1st to 5th instars (16,31±0,43), (37,04±0,71), (32,66±1,18), (66,37±4,70) and 72 days, respectively; longevity of (40,08±3,12); ratio and sexual proportion of 0,25 and 1 female: 3 males. In the field, it was observed females ovipositing in breaches and P. aquatica tree wounds; adults collected in the field presented the behaviour of forensic before copulation. The high mortality revealed that the artificial diet is inadequate for rearing of E. gigantea larvae. Females of E. gigantea, which are bigger than males show a higher longevity. The mean of mesothorax from 1st to 3th instars (second collection) were 1,51 (±0,007), 1,77 (±0,053) and 2,04(±0,033); from 1st to 4th instars (fourth collection) were 1,49 (±0,005), 1,92(±0,01), 2,75 (±0,062), 3,78(±0,14). The means of the cephalic capsules from 1st to 4th instar were 1,03(±0,0005), 1,46(±0,008), 2,09(±0,036) and 3,04(±0,078) showing a growth ratio of 1,43, 5th instar (3,75 and 4,0). It was observed that only two larvae of E. gigantea reached the 6th instar and they were feeding. Due to the absence of sobreposition of measurement in the cephalic capsules, it is reccomended the use of this parameter to determine the instars of E. gigantea. / Fundação de Amparo a Pesquisa do Estado de Alagoas / Pachira aquatica Aubl. (Bombacaceae) (falso-cacau) árvore que tem sido muito utilizada para arborização urbana, em algumas regiões do Brasil têm sido atacada por Euchroma gigantea (Linnaeus, 1758), espécie de Buprestidae (Coleoptera) cujo hábito xilofágico das larvas pode causar danos que levam à queda de árvores. Considerando que em três cidades brasileiras do Sudeste e Centro-Oeste (São Paulo, Brasília e Goiânia), têm sido registrados problemas sérios que exigiram o corte de árvores atacadas e, ainda, a dificuldade de se conduzirem estudos com insetos xilofágicos, o presente trabalho pretende determinar a duração dos ínstares larvais ao longo do desenvolvimento larval e estimar a longevidade e a razão e proporção sexual dos insetos adultos coletados em campo. Insetos adultos foram coletados na Reitoria da Universidade Federal de Alagoas (UFAL), de árvores que apresentavam os sinais do ataque do inseto (serragem e resina) e conduzidos ao Laboratório de Entomologia do Museu de História Natural da UFAL, onde foram criados em gaiolas de vidro para obtenção de massas de ovos que foram colocadas em placas-de-petri. Após a eclosão as larvas foram individualizadas também em placas-de-petri, sendo alimentadas com dieta artificial para Diatraea flavipennella (Box, 1931) (Lepidopetera: Crambidae) e também com pedaços de ramos de P. aquatica. Foram registradas as datas das ecdises e de morte de larvas. As exúvias foram conservadas para posterior mensuração da largura de mesotórax e cápsulas cefálicas. Os ovos de coloração amarronzada, eram depositados de forma agrupada. Descendentes de adultos da segunda coleta (fevereiro de 2009): período médio de incubação foi de 22,6 (±0,22) dias; média de duração dos períodos larvais do 1º ao 3º ínstares de 17,69 (±0,57), 32,46 (±2,75) e 41,0 (±3,85) dias respectivamente, razão sexual dos adultos coletados de 0,31; a longevidade média foi de 52,5 (±6,07), com razão e proporção sexual de 0,2 e 1 fêmea/4 machos. Descendentes de adultos da quarta coleta (maio de 2009): período embrionário de 24,70 (± 0,25) dias; durações do 1º ao 5º ínstares respectivamente de 16,31 (± 0,43), 37,04 (± 0,71), 32,66 (±1,18), 66,37 (± 4,70) e 72 dias; longevidade de 40,08 (±3,12) dias; e razão e proporção sexual 0,25 e 1 fêmea/3 machos. No campo, foram observadas fêmeas ovipositando em rachaduras e em ferimentos de poda nas árvores; adultos coletados no campo apresentaram comportamento de forência antes da cópula. A alta mortalidade revelou que a dieta artificial é inadequada para a criação de larvas de E. gigantea. As fêmeas, maiores que os machos, apresentam maior longevidade. As médias das medidas do mesotórax do 1º ao 3º ínstares (segunda coleta) foram 1,51 (±0,007), 1,77 (±0,053) e 2,04 (±0,033); do 1º ao 4º ínstares (quarta coleta) foram 1,49 (±0,005), 1,92 (±0,01), 2,75 (±0,062) e 3,78 (±0,14). As médias para as medidas das cápsulas cefálicas do 1º ao 4º ínstares foram 1,03 (±0,005), 1,46 (±0,008), 2,09 (±0,036) e 3,04 (±0,078) (mm) com razão de crescimento de 1,43. Somente duas larvas sofreram a 5º ecdise com os valores de 3,75 e 4,0 mm, e ainda estão se alimentando. Apenas as cápsulas cefálicas, pela não ocorrência de sobreposição de medidas, podem ser utilizadas para a determinação de ínstares em E. gigantea.
5

Biologie a stanovištní nároky ohroženého druhu stepníka Eresus moravicus (Araneae: Eresidae)v Česku / Biology and habitat requirements of endangered ladybird spider Eresus moravicus (Araneae: Eresidae) in Czechia

KREJČÍ, Tomáš January 2012 (has links)
The ladybird spider Eresus moravicus is one of our most endangered spiders. It is therefore necessary to know its habitat requirements and have at least basic knowledge of its biology to design an appropriate management to protect sites of its natural occurrence. Phytocenological analysis was made at each site and the outcomes were evaluated based on the Ellenberg´s indicator values. Also slope and exposure, litter layer and the quantity of rubbel were measured on the localities. Individuals were taken from burrows for the measurement of the prosoma length (investigation of the length of the life cycle). Exuviae were collected from the same burrows for measurement of the prosoma length. From these data the number of instars was determined. Prey remains were taken at most of those sites from 5?10 burrows and determined. Offsprings from several maternal burrows were taken, counted and weighted (research of fecundity of females). Weight of offsprings is important also in terms of their dispersion ability. The offsprings ability to balloon was investigated experimentally in laboratory conditions. The ladybird spider Eresus moravicus occurs in warm regions with high intensity of irradiation, mostly on the southern and southwestern slopes. Sites are characterized by poor herbaceous vegetation without trees and shrubs and by a thin layer of humus. Female lives for four years and the male for three years. The number of instars can reach to 13. Beetles (Coleoptera) are the most importent prey, the importent component of food are ants (Formicidae), too. Eresus moravicus has more offsprings than Eresus sandaliatus and Eresus kollari, more eggs in the cocoon than E. kollari and heavier offsprings than E. kollari and E. sandaliatus. In offsprings of E. moravicus and E. kollari pre-ballooning behavior of two types was observed: "tip-toe" behavior and "drop and swing" behavior.
6

História natural e ecologia da aranha Aglaoctenus lagotis (Araneae, Lycosidae)

Moreira, Vanessa Stefani Sul 26 February 2010 (has links)
CHAPTER I: The present study has the objective to describe the life history of Aglaotenus lagotis since the youngest birth until adulthood, analysing the number of eggs in each cocoon, the birth rate, the instar number, sexual ratio and development time until adulthood, quantifying the size cephalothoraxes during all the stages of the development. The results indicate that the species is able to produce two egg sacs during the reproductive period with twelve instars after the outbreak. The youngest, during the development had the greatest a mortality rate on the three first instars, what characterizes a type III survival curve. During the adulthood the sexual ratio was turned to the female, and there is no significant differentiation between the cephalothoraxes width between males and females in laboratory environment, what makes it possible to, be considered a monomorphic species. The sexual dimorfism was observed on the coloration. Males show a light brown coloration and the female show a dark one. This study provides an opportunity to evaluate all the phases of life cycle of Lycosidae A. lagotis, what can help on the initial construction of studies about the post-embryonic development of the species, offering comparative parameters with other species from this family. CHAPTER II: The present study shows the description of the sexual behavior and the maternal care of the spider A. lagotis (Lycosidae), testing by experiments the hypothesis that the male of A. lagotis is attracted by chemical cues in the sheet web built by the female. A maternal care behavior is described, testing the hypothesis that youngest from the studied species that had maternal care have a greater fitness than youngest without the maternal care. The study made it clear that males are able to observe, note, identify realize chemical cues in the web, telling virgin females from females that were fertilized. It was possible to quantify e categorize the sexual behavior of the males into three different categories: court, pre-mate and mate. After the mate, the females built an cocoon that was transported adhered in the spinnerets and hold by the last pair of legs. After the outbreak of the eggs, the youngest migrated to a dorsal region of the mother s body for five days. It was observed during the maternal care that the mother eliminates a yellowish drop from its cheliceraes which is collected by the youngest. During the development of the youngest until the adulthood, the youngest that have the presence of their mother in the first stages of life have a greater survival, if compared with the ones that do not have the presence of their mother. So, for the A. lagotis species, by its abundance and wide distribution represent an interesting model of study for the hypothesis test in behavioral ecology, which makes possible new comparative analyses with other species of Lycosidae. CHAPTER III: The present study shows the ecological aspects of A. lagotis from two distinct populations, in a semi-deciduous dry forest in Araguari municipality, Minas Gerais. the study was developed in four distinct periods october 2008, january, april and july 2099, in two different sites. the results show that A. lagotis is a seasonal species, with an aggregated distribution and with a strong parental similarity component between the individuals from the same region. The life history of A. lagotis seems to be characterized by seasonal aspects, seen that some components of its life cycle show a well defined period of ocorrence. As long as they grow, both the area and the height of the web get bigger with the individual size, what suggests that webs progressively bigger and taller are necessary for the capture of prey enough for the maintenance of the individual biomass. Despite of happening little variation in the number of spider tenant individuals associated to the vertical interception web between the studied areas (except for April), a positive correlation was characterized between these variables in all the samples. It means that, the greater the volume of the vertical web, the greater the number of parasite spiders. So, the variations in the densities of spiders between the study sites and through time in each site, observed in this study, can be the result of the interaction between several factors, as the availability of food, climate factors and other parameters that must be investigated in future studies. / CAPÍTULO I: O presente estudo teve como objetivo de descrever a história de vida de Aglaoctenus lagotis desde o nascimento dos filhotes até a fase adulta, analisando o número de ovos em cada ovissaco, a taxa de nascimento, o número de instares, razão sexual e o tempo de desenvolvimento até a fase adulta, quantificando o tamanho do cefalotórax durante todas as etapas de desenvolvimento. Os resultados apresentados indicaram que a espécie estudada é capaz de produzir dois sacos de ovos durante o período reprodutivo e que após a eclosão o número de instares registrados foi de 12. Os filhotes, durante o desenvolvimento, tiveram uma taxa de mortalidade maior nos três primeiros instares, caracterizando uma curva de sobrevivência do tipo III. Na fase adulta a razão sexual foi voltada para a fêmea e não existindo diferenciação significativa entre a largura do cefalotórax entre macho e fêmeas em ambiente de laboratório, podendo, portanto ser considerada uma espécie monomórfica. O dimorfismo sexual encontrado foi na coloração da cutícula, machos apresentaram uma coloração marrom clara e a fêmea uma coloração marrom escura. Este estudo proporcionou uma oportunidade de avaliar todas as fases de vida do Lycosidae A. lagotis, podendo auxiliar na formação inicial de estudos sobre desenvolvimento pós-embrionário da espécie oferecendo parâmetros comparativos com outras espécies desta família. CAPÍTULO II: O presente estudo apresenta a descrição do comportamento sexual e do cuidado maternal da aranha Aglaoctenus lagotis (Lycosidae), testando experimentalmente a hipótese de que o macho é atraído por odores deixados na teia de lençol construída pela fêmea. Foi descrito o comportamento de cuidado maternal, testando a hipótese que filhotes da espécie estudada que tiveram cuidado maternal possuem o fitness maior do que filhotes sem o cuidado maternal. O estudo evidenciou que machos são capazes de perceber o odor presente na teia, diferenciando fêmeas virgens receptivas de fêmeas já fecundadas. Foi possível quantificar e categorizar o comportamento sexual dos machos em três categorias distintas: corte, pré-cópula e cópula. Depois da cópula as fêmeas construíram uma ooteca que foi transportada aderida nas fiandeiras e segurada pelo último par de pernas. Após a eclosão dos ovos os filhotes migraram para a região dorsal do corpo da mãe e permaneceram durante cinco dias. Foi observado durante o cuidado maternal a mãe eliminando uma gota amarelada de suas quelíceras,a qual é coletada pelos filhotes. Durante o desenvolvimento dos jovens até a fase adulta, os filhotes que tiveram a presença da mãe nos primeiros estágios de vida obtiveram uma sobrevivência maior, se comparado com os que não tiveram a presença da mãe. Portanto, devido à sua abundância e ampla distribuição a espécie Aglaoctenus lagotis representa um interessante modelo de estudo para teste de hipóteses em ecologia comportamental, possibilitando análises comparativas com outras espécies de Lycosidae. CAPÍTULO III: O presente estudo apresenta aspectos da ecologia da Aglaoctenus lagotis a partir de duas populações distintas, em floresta semi-decidual seca no Município de Araguari, Minas Gerais. O estudo foi desenvolvido em quatro períodos distintos - outubro de 2008, janeiro, abril e julho de 2009, em dois locais diferentes. Os resultados indicaram que A. lagotis é uma espécie sazonal, com distribuição agregada e com um forte componente de similaridade parental entre os indivíduos de uma mesma região. A história de vida de A. lagotis parece ser marcada por aspectos sazonais, sendo que alguns componentes de seu ciclo de vida apresentam um período bem definido de ocorrência. À medida que crescem, tanto a área da teia como a altura da teia aumentam com o tamanho do indivíduo, o que sugere que teias progressivamente maiores e mais altas são necessárias para a captura de presas suficientes para a manutenção da biomassa individual. Apesar de ocorrer pouca variação no número de indivíduos de aranhas inquilinas associadas à teia de interceptação vertical entre as áreas estudas (com exceção de abril) foi caracterizada uma correlação positiva entre estas variáveis em todas as amostras. Ou seja, quanto maior o volume da teia vertical maior número de aranhas parasitas. Portanto, as variações nas densidades de aranhas entre os locais de estudo e ao longo do tempo em cada local, observados neste estudo, podem ser resultado da interação entre diversos fatores, como disponibilidade de alimento, fatores climáticos e outros parâmetros que devem ser investigados em estudos posteriores. / Doutor em Ecologia e Conservação de Recursos Naturais
7

Stav dorsoabdominálních pachových žláz u imag ploštic taxonu Pentatomomorpha (Heteroptera) / Condition of dorsoabdominal scent glands in adults of the true bugs from the taxon Pentatomomorpha (Heteroptera)

Křížková, Petra January 2014 (has links)
Existence of larval dorsoabdominal scent glands (DAGs) together with occurence of adult metathoracic scent glands is one of the important autapomorphic characters of taxon Heteroptera within taxon Insecta. DAGs can persist until adults in some species of this taxon. The persistence of DAGs were proved also in members of infraorder Pentatomomorpha. Targets of this thesis are: collect the knowledge about persistent adult DAGs in selected representative members of important families of taxon Pentatomomorpha; study and compare the condition of the DAGs in the oldest larval instars and adults; clarify the significance of existence the openings of conducting ductules of proper glandular units in reservoir intima of DAGs in study of the persistence of these glands. For study were used stereomicroscope, light and scanning electron microscope. Key words: Pentatomomorpha, Heteroptera, dorsoabdominal scent glands, openings of conducting ductules of glandular units, larvae of 5th instar, persistence in adults, persistence patterns, light microscope, scanning electron microscope

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