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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.
71

Bases para o cultivo org?nico de feij?o-caupi [Vigna unguiculata L. (Walp.)] no estado do Rio de Janeiro. / Organic farming systems for cowpea [Vigna unguiculata L. (Walp.)] in the state of Rio de Janeiro.

Guedes, Rejane Escrivani 25 March 2008 (has links)
Made available in DSpace on 2016-04-28T14:59:00Z (GMT). No. of bitstreams: 1 Rejane Escrivani Guedes.pdf: 2537678 bytes, checksum: fa415f1591e33c3b7c367223fc134c67 (MD5) Previous issue date: 2008-03-25 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior / Cowpea genotypes submitted to organic management were evaluated for grain yield and green manure, as well as intercropped with corn, under field conditions of Serop?dica, state of Rio de Janeiro. In the year of 2005, 53 cowpea genotypes were compared at the Integrated Agroecology Produc tion System ( SIPA Km 47 Agroecologic Farm) relating to qualitative and quantitative agronomic traits. Data were treated by following univariate and multivariate statistical analysis. Significant differences were detected with respect to all the evaluated parameters. Genotypes EES-02, EES-08, EES-26, EES47, Feij?o-Caupi and Feij?o Mau? showed favourable attributes for immature (=green) grain yield. They presented determinate growth habit with moderate branchding and flowering stage up to 45 days after sowing, only differing by pod and grain colors. Univariete analysis demonstrated high variability among cowpea genotypes. However, multivariate analysis was more efficient to joint selected agronomic traits for identification of genotyp ic groups, which can be important in cowpea breeding programs. Cowpea and corn intercrops also submitted to organic cultivation were evaluated by means of two field experiments carried out at SIPA. In Experiment 1, the cowpea cultivars Mau?, BRS Mil?nio and Olho de Peixe were intercropped with corn (cv. AG-1051) to function as green manures. A randomized blocks design was employed in factorial 2x3 scheme (two corn plant spacing x three cowpea cultivars). In Experiment 2, Mau? cowpea and AG-1051 corn were intercropped for harvesting immature (=green) grains and spikes, respectively. Treatments consisted of four time intervals between cowpea and corn sowing. As for Experiment 1, corn planted in double rows favoured cowpea aboveground biomass production, probably due to a greater amount of light admitted into the system. Results from Experiments 2 indicated that intercrop with cowpea did not decrease corn yield which reached averages of 9,5 and 5,9 Mg ha-1 of ears with and without straw, respectively. Regarding cowpea grain yield of Mau? cultivar its single crop was superior to the intercrops exceeding 1400 kg ha-1. Treatment corresponding to 21 days of interval between cowpea and corn sowing differed from the other types of intecrops, with yield attaining 978,75 ka ka-1. It is concluded that the intercropping system can se adopted in the region without risks of lowering corn yield due to competition, being three weeks (21 days) the most adequate time interval between sowing. / Foi avaliado, em sistema org?nico de produ??o, o desempenho de gen?tipos de feij?o-caupi com potencial para produ??o de gr?os verdes e aduba??o verde, e em cons?rcios com o milho, nas condi??es da Baixada Fluminense, munic?pio de Serop?dica, estado do Rio de Janeiro. No ano de 2005, em ?rea do SIPA, (Sistema Integrado de Produ??o Agroecol?gica Fazendinha Agroecol?gica Km. 47 ), foram avaliados 53 gen?tipos de feij?o-caupi, segundo caracter?sticas fitot?cnicas qualitativas e quantitativas. Os dados foram submetidos a an?lise de vari?ncia univariada e a an?lise multivariada. Houve diferen?a significativa para todos os par?metros avaliados. Os gen?tipos EES-02, EES-08, EES-26, EES-47, Feij?o-Caupi e Feij?o Mau? reuniram caracter?sticas mais adequadas para colheita de gr?os verdes, apresentando porte semi-ramador, h?bito de crescimento determinado, com florescimento at? 45 dias ap?s semeadura, diferindo apenas pela colora??o da vagem e do gr?o. Os resultados da an?lise univariada demonstraram alta variabilidade entre os gen?tipos. Por?m, para o caso de se reunir v?rios atributos fitot?cnicos, constituindo grupos de gen?tipos, a an?lise multivariada se mostrou mais eficiente e pode ser de valia para o melhoramento do feij?o-caupi. Foi avaliado, ainda, o desempenho agron?mico dos cons?rcios do milho com o feij?o-caupi submetidos ao manejo org?nico, atrav?s de dois experimentos conduzidos no SIPA. No Experimento 1, avaliou-se o desempenho de tr?s cultivares de feij?o-caupi para aduba??o verde do milho (cv. AG-1501) em cons?rcios simult?neos. As cultivares de feij?o-caupi Mau?, BRS Mil?nio e Olho de Peixe foram utilizadas, adotando-se delineamento de blocos ao acaso, em esquema fatorial 2 x 3 (dois espa?amentos de milho e tr?s cultivares de feij?ocaupi). No Experimento 2, avaliou-se o cons?rcio entre feij?o-caupi (cv. Mau?) e milho (cv. AG-1051) para colheitas de gr?os verdes e de espigas verdes, respectivamente. Os tratamentos constaram de quatro intervalos entre as semeaduras de feij?o-caupi e de milho. No Experimento 1, o espa?amento do milho em fileiras duplas favoreceu a produ??o de biomassa a?rea fresca de feij?o-caupi, muito provavelmente pela maior entrada de luz no sistema. Os resultados do Experimento 2 indicaram que o cons?rcio n?o interferiu na produtividade do milho, colhendo-se, em m?dia, 9,5 e 5,9 Mg ha-1 de espigas verdes empalhadas e desempalhadas, respectivamente. Com rela??o ? produ??o de gr?os verdes da cv. Mau? de feij?o-caupi, o monocultivo superou os cons?rcios com o milho, ultrapassando 1400 kg ha-1. O cons?rcio correspondente a 21 DAM (dias antes do milho) diferiu dos demais tipos de cons?rcio, sendo superior, em produ??o, que atingiu 978,75 kg ha-1. Concluiu-se que o sistema de cons?rcio com o feij?o-caupi pode ser adotado na regi?o sem risco de perdas na produtividade do milho por efeito de competi??o, sendo de tr?s semanas (21 DAM) o intervalo mais adequado entre as semeaduras.
72

Etude de la sismicité intraplaque de la région de Gazli (Ouzbékistan) et localisation de la déformation sismique

Bossu, Rémy 11 January 1996 (has links) (PDF)
Entre 1976 ct 1984, trois séismes de magnitude 7 ont affecté la région intraplaque de Gazli (Ouzbékistan), région de 50x70 km2 auparavant qualifiée de peu sismique. La présence d'un important champ de gaz à proximité immédiate des épicentres suggéra la possibiiité d'une relation entre l'exploitation d'hydrocarbures et l'occurrence de cette sèquence sismique. Trois approches différentes, approche sismologique, tectonique et mécanique furent nécessaires pour contraindre le modèle proposé. D'après ce dernier, l'activité sismique majeure de la région de Gazli est due à la propagation, à l'Ouest du Pamir, de la déformation engendrée par la collision lnde-Asie. ' Le confinement à l'Ouest du Pamir impose que les mouvements décrochants dextres initiés aux abords du poinçon soient absorbés rapidement sur la plateforme par des structures compressives. L'existence de cette structure d'orientation NE-SW est confirmée par l'analyse de photos satellites et par la présence à l'Ouest de la zone épicentrale, d'un bassin compressif post-Oligocène. Quelque soit la magnitude des séismes considérés, des événements de ML > = 3.2 enregistrés en 1991 aux chocs principaux de Ms= 7.0, la sismicité de Gazli se caractérise par une grande variabilité de solutions focales. Pourtant, diverses inversions de contraintes démontrent qu'un état des contraintes unique, lui-même gouverné par la tectonique régionale, peut expliquer ces diverses solutions focales. Pour une structure tectonique donnée, nous proposons que la complexité de localisation de la déformation sismique, déjà observée dans plusieurs zones intraplaques, soit une conséquence du faible déplacement accommodé par cette structure. Nous parlerons alors de structure immature, à opposer à une structure mature, elle même caractérisée par la présence de failles bien développées. Ce concept a de nombreuses implications, notamment en risque sismique. C'est pourquoi nous proposons une méthode statistique permettant de quantitier la "maturité" d'une structure à partir de quelques dizaines de solutions focales.
73

Estrogens Rapidly Enhance Neural Plasticity and Learning

Phan, Anna 24 July 2013 (has links)
This thesis examines the rapid, non-genomic effects of estrogens on neural plasticity and learning. Estrogens are classically known to affect gene transcription events, however they have more recently been found to also rapidly activate second messenger systems within 1hr of administration. Therefore, we first examined the rapid effects of 17β-estradiol, and an estrogen receptor (ER) α and ERβ agonist on three different learning paradigms: object placement, object recognition, and social recognition. We found that both systemic injections and intrahippocampal delivery of 17β-estradiol and the ERα agonist improved performance on all 3 learning paradigms within 40min of hormone administration. However, the ERβ agonist administered systemically or intrahippocampally, improved performance only on the object placement learning paradigm, while having no effect on object recognition, and impairing social recognition at high doses. To elucidate how estrogens might rapidly affect learning, we examined how estrogens rapidly affect the neural plasticity of CA1 hippocampal neurons. We found that 17β-estradiol and the ERα agonist increased dendritic spine density in CA1 hippocampal neurons within 40min of administration, suggesting that estrogens rapidly increase the density of synapses within this brain region. Conversely, the ERβ agonist did not affect spine density, or decreased spine density. In addition, by using whole-cell patch clamp recordings of CA1 pyramidal neurons, we were able to determine that 17β-estradiol and the ERα agonist rapidly reduced AMPA receptor (but not NMDA receptor) mediated membrane depolarizations after 15min of hormone application. Similar to above, the ERβ agonist had no effect on AMPA or NMDA receptor mediated membrane depolarizations. These data suggest that estrogens rapidly promote the development of immature synapses (which contain low levels of synaptic AMPA receptors) within the CA1 hippocampus. Immature spines provide synaptic sites at which new memories can be stored and are thought of as “learning spines” (Kasai et al, 2003). Therefore, estrogens (through ERα) may rapidly induce the formation of hippocampal immature spines to promote learning. / Funded by NSERC
74

Estágios imaturos, morfologia interna e morfometria de Platyscytus decempunctatus (Carvalho, 1945) (Heteroptera: Miridae) / Immature stages, internal morphology and morphometry of Platyscytus decempunctatus (Carvalho, 1945) (Heteroptera: Miridae)

Pires, Evaldo Martins 03 July 2006 (has links)
Made available in DSpace on 2015-03-26T13:30:34Z (GMT). No. of bitstreams: 1 texto completo.pdf: 2240494 bytes, checksum: ff83534e651c63b07021f882e2c03334 (MD5) Previous issue date: 2006-07-03 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Platyscytus decempunctatus (Heteroptera: Miridae) is a small mirid (three to four mm) found in plants of Solanum cernuum Vell. (Solanaceae), where it develops throughout its life cicle. The study of the insect internal morphology describes the basic internal tracts of the salivary glands, the midgut, the male and female reproductive structures and the Malpighian tubules. This species has salivary glands of the tubular form, an ovary of the telotrophic type with three ovarioles in the right ovary and five in the left one. In the male reproductive trait was observed the presence of only one pair of accessory glands of tubular or sacs-like form. The phytophagous feeding habitat was confirmed by the observation of chlorophyll pigments in the gut of all dissected specimens. The Malpighian tubules are formed by a unique layer of cells with microvills. The description and the diagnosis of the stages from egg to adult of P. decempunctatus was also studied inclunding male reproductive organ and trait. A morfometric study of 27 morphological traits of P. decempunctatus was carried out to recognize differences between sexos and seasons in insects collected throughout a year in Viçosa, MG. Interpopulation differences were also investigated in a subsequent study with 23 populations collected collected from the states of Minas Gerais and Rio de Janeiro. A study of spot variations among these populations was carried out, showing the spot pattern observed on the description of type specimen and 27 more spot patterns also observed in P. decempunctatus. New occurrences for the geographic distribution were registred for this species strengthening the interelations with its host plant, S. cernuum. / Platyscytus decempunctatus (Heteroptera: Miridae) é um mirídeo de pequeno porte (três a quatro milímetros) encontrado em plantas de Solanum cernuum Vell. (Solanaceae), onde desenvolve todas as etapas do seu ciclo de vida. O estudo da morfologia interna desse inseto descreve as estruturas básicas das glândulas salivares, do intestino médio, do aparelho reprodutor masculino e feminino e túbulos de Malpighi. Essa espécie apresenta glândula salivar em formato tubular, o ovário do tipo meroístico telotrófico com três ovaríolos no ovário direito e cinco no esquerdo. No sistema reprodutor masculino verificou-se a presença de apenas um par de glândulas acessórias em formato de sacos ou tubos. Foi confirmada a hipótese de fitofagia pela presença de pigmentos de clorofila no intestino dos exemplares dissecados. Os túbulos de Malpighi são formados por uma única camada de células com microvilosidades. A descrição e diagnósticos dos estágios de ovo a adulto de P. decempunctatus inclui caracteres da genitália masculina. Com base na morfometria de 27 caracteres morfológicos de P. decempunctatus foram analisadas diferenças entre sexos e estações (seca e úmida) no período de um ano em Viçosa, MG. Foi também averiguada diferenças entre os sexos e locais de coletas em 23 populações coletadas nos estados de Minas Gerais e Rio de Janeiro. Um estudo sobre as variações das manchas dorsais entre populações foi realizado, considerando-se as dominâncias para cada localidade dos 27 padrões encontrados para P. decempunctatus. Foram feitos novos registros de distribuição geográfica dessa espécie na relação com Solanum cernuum, sua planta hospedeira.
75

Metacognitive strategies for learning disabled adolescents in specialised education

Masureik-Berger, Arlene Roslyn 1 January 1994 (has links)
Learning disabilities are a life-long problem for many individuals. Besides the adjustments all adolescents experience in life, learning disabled adolescents must contend with academic problems at school which have a drastic effect on their selfesteem. This becomes particularly evident when these pupils face the demands of the secondary school syllabus where they have to be able to concentrate, read for information, memorise facts, answer questions and solve problems, and write assignments. By the time learning disabled adolescents reach secondary school they have already experienced so much failure that they become passive towards their studies. Teaching these pupils metacognitive learning strategies covering these skills helps them to become more independent learners. Through executive training procedures they are assisted to become more involved in their studies, the promotion of better self-regulation and self-monitoring is fostered, and as their scores improve, so does their motivation and selfconcept / Educational Studies / M.Ed. (Orthopedagogics)
76

Vespas sociais (Hymenoptera, Vespidae) em áreas antrópicas

Alvarenga, Raphaela de Barros 10 February 2012 (has links)
Submitted by Renata Lopes (renatasil82@gmail.com) on 2016-05-20T19:17:03Z No. of bitstreams: 1 raphaeladebarrosalvarenga.pdf: 736205 bytes, checksum: f06192e913497d47b4706db973f03b3c (MD5) / Approved for entry into archive by Adriana Oliveira (adriana.oliveira@ufjf.edu.br) on 2016-07-02T11:28:01Z (GMT) No. of bitstreams: 1 raphaeladebarrosalvarenga.pdf: 736205 bytes, checksum: f06192e913497d47b4706db973f03b3c (MD5) / Made available in DSpace on 2016-07-02T11:28:01Z (GMT). No. of bitstreams: 1 raphaeladebarrosalvarenga.pdf: 736205 bytes, checksum: f06192e913497d47b4706db973f03b3c (MD5) Previous issue date: 2012-02-10 / As vespas sociais estão amplamente distribuídas em todo o continente. No ambiente urbano tem se observado a nidificação de algumas espécies de vespas sociais em locais próximos a presença humana, como por exemplo, a espécie Mischocyttarus cassununga. Os objetivos deste trabalho foram verificar a ocorrência de vespas sociais em jardins urbanos, durante a estação quente e úmida; e fria e seca e avaliar a agressividade, o comportamento de defesa e o desenvolvimento das colônias de M. cassununga, diante de perturbações nos ninhos e simulação de ataques de formigas, no município de Juiz de Fora, Minas Gerais. Para verificar a ocorrência de vespas sociais em jardins urbanos, o estudo foi conduzido durante um ano, em sete jardins urbanos, com seis vistorias em cada estação. Durante a estação quente e úmida foram encontradas 145 colônias: Protopolybia exigua (n= 81), Polybia platycephala (n=40) e Mischocyttarus cassununga (n=24). Já na estação fria e seca foram encontradas 87 colônias: P. exigua (n=47), P. platycephala (n=29) e M. cassununga (n=11). Na estação quente e úmida a densidade foi superior para todas as espécies. Nas duas estações o índice de dominância para as colônias de P. exigua (d=0,55) foi superior em relação às outras espécies encontradas (d= 0,30 para P. platycephala e d=0,15 para M. cassununga). Todas as colônias nidificavam em vegetação: Livistona chinensis (n=161) e Dracaena fragans (n=71). O número de colônias encontradas demonstrou uma forte correlação positiva com o tamanho da área verde arbórea (r=0,9643; p=0,0005) e com o tamanho da área verde de nidificação (r=0,8571; p=0,0137), assim como com o tamanho da área total dos jardins urbanos(r=0,9286; p=0,0025). A altura das colônias em relação ao solo variou de dois a mais de quatro metros. As espécies que estavam entre dois e quatro metros de altura foi significativamente maior (χ²=21,930; p<0,0001) do que as colônias encontradas nas demais alturas. Para avaliar o comportamento de defesa da espécie M. cassununga, o estudo foi realizado entre os meses de abril a julho de 2011 no campus da Universidade Federal de Juiz Fora, utilizando-se sete colônias controle e sete colônias tratamento. As colônias foram mapeadas e durante 18 dias as colônias tratamento foram perturbadas com uma bola de malha vermelha agitada. Posteriormente foi feita uma simulação de ataque de formigas contra todas as colônias (controle e tratamento). Os resultados mostraram que durante a perturbação com a bola as colônias se apresentaram mais agressivas no começo e possivelmente se habituaram a bola com o decorrer da perturbação. Durante a simulação de ataque de formigas, não houve diferença significativa (z=0,133; p=0,895) na freqüência comportamental entre as colônias controle e tratamento. O desenvolvimento dos imaturos também não demonstrou diferença significativa para ovos (z=1,351; p=0,177), larvas (z=1,293; p=0,196) e pupas (z=0,925; p=0,355) entre as colônias controle e tratamento. Porém houve uma diferença significativa (z=2,300; p=0,021) no desaparecimento de ovos entre as colônias controle e tratamento. Houve também uma diferença significativa entre o desaparecimento de larvas das colônias controle e tratamento de M. cassununga (z=2,108; p=0,035). Com este estudo foi possível perceber que há uma maior ocorrência das vespas sociais na estação quente e úmida em jardins urbanos e uma relação direta entre a presença de recursos oferecidos nesta estação e a ocorrência de vespas sociais. Foi possível demonstrar também que apesar da baixa agressividade, as colônias de M. cassununga exibem comportamentos agressivos em defesa de suas colônias e que as perturbações influenciam no desaparecimento de imaturos (ovos e larvas), diminuindo o surgimento de novos adultos. / The social wasps are widely distributed around the continent. In the urban environment has been observed the nesting of some social wasps species and their socialization with the human presence, for exemple the specie Mischocyttarus cassununga. The objectives of this study were to verify the occurrence of social wasps in urban gardens during the hot, humid, cold and dry and evaluate their aggression, and colonies defensive behavior development of M. cassununga, about turmoil in nests and of ants attacks simutalions, in the Juiz de Fora municipality , Minas Gerais. To check the occurrence of social wasps in urban gardens, the study was conducted during one year in seven urban gardens, making six surveys at each station. During the hot and humid 145 colonies were found: Protopolybia exigua (n=81), Polybia platycephala (n=40) and Mischocyttarus cassununga (n=24). In the cold season and dry 87 colonies were found: P. exigua (n=47), P. platycephala (n=29) and M. cassununga (n=11). In the hot and humid the density was higher in all species. In two seasons "the" dominance index for colonies of P. exigua (d=0.55) was superior compared to other species found (d=0.30 for P. platycephala and d=0.15 for M. cassununga). All colonies nesting in vegetation: Livistonia chinensis (n=161) and Dracaena fragans (n=71). The number of colonies found showed a strong positive correlation with the size of green tree (r=0.9643, p=0.0005) and with the size of nesting green area (r=0.8571, p=0.0137), as well as the total area size of urban gardens (r=0.9286, p=0.0025). The height colonies from the ground ranged from two tand four meters more. The species that was between two and four meters in height was significantly higher (χ²=21.930; p<0.0001) than those found in other colonies heights. To evaluate the defense of M. cassununga specie, the study was conducted between April and July 2011 on the campus of University Juiz de Fora, using seven control colonies and seven treatment colonies. The colonies were mapped and during 18 days the treatment colonies were disturbed by a agitated restless ball of red. It was later made a mock attack against all ant colonies (control and treatment). The results showed during the disturbance with the ball the colonies had more aggressive in the beginning and possibly have accustomed to the ballduring the perturbation. During the attack simulation by ants, there was no significant difference (z=0.133, p=0.895) in the behavior frequency between control and treatment colonies. The immature development also showed no significant difference for eggs (z=1.351, p=0.177), larvae (z=1.293, p=0.196) and pupas (z=0.925, p=0.355) between control colonies and treatment colonies. However, there was a significant difference (z=2.300, p=0.021) in disappearance of eggs between the control and treatment colonies. There was also a significant difference between the disappearance of larvae from control and treatment colonies M. cassununga (z=2.108, p=0.035). With this study it was revealed that there is a higher occurrence of social wasps in the hot season and humid in urban gardens and a direct relationship between the features presence offered in this season and the occurrence of social wasps. It was also possible to demonstrate that despite the low aggressiveness, the colonies M. cassununga showed aggressive behavior in defense of their colonies and that disturbances influence the disappearance of immature (eggs and larvae), reducing the emergence of new adults.
77

Biologia e ecologia comportamental da vespa social Polybia platycephala (Richards, 1978) (Hymenoptera, Vespidae, Epiponini)

Rocha, Monalisa de Paula 28 February 2011 (has links)
Submitted by Renata Lopes (renatasil82@gmail.com) on 2016-07-21T11:39:31Z No. of bitstreams: 1 monalisadepaularocha.pdf: 972026 bytes, checksum: 1d1124c048f5e7456925bd61ed099336 (MD5) / Approved for entry into archive by Adriana Oliveira (adriana.oliveira@ufjf.edu.br) on 2016-07-22T15:28:17Z (GMT) No. of bitstreams: 1 monalisadepaularocha.pdf: 972026 bytes, checksum: 1d1124c048f5e7456925bd61ed099336 (MD5) / Made available in DSpace on 2016-07-22T15:28:17Z (GMT). No. of bitstreams: 1 monalisadepaularocha.pdf: 972026 bytes, checksum: 1d1124c048f5e7456925bd61ed099336 (MD5) Previous issue date: 2011-02-28 / Polybia platycephala (Richards, 1978) é uma vespa social enxameante que possui seu ninho constituído de várias filas de favos horizontais cobertos favo-a-favo por um envelope. Neste estudo caracterizou-se o padrão de fundação, arquitetura do ninho, o padrão de estocagem de recursos nas colônias, o ciclo colonial, a população, os estágios imaturos, e o número de ínstares larvais de P. platycephala. Além disso, o macho da espécie é descrito e ilustrado. No período de novembro de 2009 a novembro de 2010, foram estudadas 95 colônias em áreas antrópicas do município de Juiz de Fora, MG. Para descrição do padrão de fundação, foram realizadas observações ―ad libitum‖ em quatro enxames. Para analisar a arquitetura do ninho foram considerados os seguintes dados: coloração, comprimento e largura do orifício de entrada, e dimensões do ninho. O ângulo de orientação das colônias foi estabelecido com uma bússola posicionada abaixo dos ninhos. Através da dissecção de 15 colônias, foi verificada a fase de desenvolvimento e o número de: adultos, total de células, células vazias, ovos, larvas, e pupas. Foram mensuradas, a maior largura e o maior comprimento de 100 ovos, e a largura máxima da cápsula cefálica de 400 larvas e 120 pupas, sendo o número de ínstares larvais determinado de acordo com a Regra de Dyar. Foi possível determinar que antes da construção das primeiras células, P.platycephala constrói uma fina base de material vegetal sobre o substrato. O processo de construção inicial do ninho durou de 10 a 15 dias. A nidificação na vegetação foi maior do que em substratos construídos (x²= 53,063; p < 0,0001). Em média, os ninhos apresentaram 2115 ± 1234 (328 - 4723) células, podendo conter até oito favos, e estavam situados a cerca de 3,0 metros do solo. A distância média entre os favos foi de 0,67 ± 0,09 cm (0,53 - 0,85). Houve diferença sazonal no sentido de orientação dos ninhos fundados pela espécie, com ninhos na estação chuvosa orientados principalmente para o sul e ninhos na estação seca orientados para o norte. Os eventos de fundação e abandono das colônias ocorreram em todas as épocas do ano. As colônias produziram 510,26 ± 403,21 (71 – 1492) adultos e encontravam-se em diferentes fases do ciclo colonial. As oviposturas nos favos ocorreram geralmente do centro para a periferia, com pupas nas células centrais circundadas de larvas em diferentes ínstares, seguida de ovos e células vazias na periferia. Constatou-se a presença de casulos de parasitóides no interior das células de cinco ninhos. Foi observada a estocagem de substância açucarada em 80% das colônias (seis em fase de produção de operárias, três em fase de quiescência, duas na produção de machos e um na pré-emergência). O armazenamento ocorreu sempre em células vazias (92,63%), células com presas (4,88%), células com ovos (2,0%) ou células com larvas pequenas (0,5%). A estocagem de presas foi observada em duas colônias, dentro das células ou entre os favos dos ninhos. As larvas possuem cinco ínstares, com uma razão média de crescimento de 1,57. Os machos de P. platycephala distinguem-se das fêmeas por características como o clípeo amarelo com ou sem pilosidade prateada; antena não tão robusta, com 13 segmentos; gena estreita; gáster com 1-6 tergitos. / Polybia platycephala (Richards, 1978) is a social swarming wasp which has its nest constituted of several lines of horizontal combs covered each one of them by an envelope. In this study, it was characterized the foundation pattern, the nest architecture, the storage pattern of resources in the colony, the colonial cycle, the population, the immature stages, and the number of larval instars of P. platycephala. Furthermore, the male of the species is described and illustrated. During the period from November 2009 the November 2010, 95 colonies were studied in antropic areas of the city of Juiz de Fora, MG. For the description of the foundation pattern, some ―ad libitum‖ observations were performed on four swarms. For analyzing the architecture of the nest, the following data were considered: coloration, length and width of the entrance orifice, and nest dimensions. The orientation angle of the colonies was established with a compass. Through the dissection of 15 colonies, it was verified the development phase and the number of adults, total of cells, vacant cells, eggs, larvae, and pupae. The largest width and the largest length of 100 eggs and the maximum width of the cephalic capsule of 400 larvae and 120 pupae were measured, and the number of larval instars is determined according to the Dyar’s Rule. It was possible to determinate that before the construction of the first cells, P. platycephala builds a slim base of vegetal material on the substrate. The initial process of construction has lasted from 10 to 15 days. The nidification in the vegetation was bigger than in constructed substrates (x²= 53.063; p < 0.0001). On average, the nests presented 2115 ± 1234 (328 - 4723) cells, which can contain up to eight combs, and they were situated about 3.0 meters above ground. The average distance between the combs was about 0.67 ± 0.09 cm (0.53 – 0.85). There was a seasonal difference in the orientation meaning of the nests founded by the species, with nests oriented mainly towards the south in the rainy season, and the north in the dry season. The events of foundation and abandonment of the colonies occurred all the year round. The colonies produced 510.26 ± 403.21 (71 – 1492) adults and these were found in different phases of the colonial cycle. The postures in the combs occurred generally from the center to the periphery, with pupae in the central cells surrounded by larvae in different instars, followed by eggs and vacant cells in the periphery. It was verified the presence of cocoons of parasitoids in the cells of five nests. It was observed the storage of sugary substance in 80% of the colonies (six in worker production stage, three in quiescence stage, two in the production of males and one in the pre-emergence). The storing always occurred in vacant cells (92.63%), cells with preys (4.88%), cells with eggs (2.0%) or cells with small larvae (0.5%). The storing of preys was observed in two colonies, inside the cells and between the combs of the nests. The larvae have five instars, with a a mean ratio of growth of 1.57. The males of P. platycephala differ from the females with characteristics like the yellow clypeus with or without silver hairiness; antenna not so robust, with 13 segments; narrow gena; gaster with 1-6 tergitos.
78

Managing the Implementation of Metal Additive Manufacturing : A Case Study at SAAB

Weimar, Emily, Antila, Eric January 2023 (has links)
As industries are transitioning towards mass customisation, manufacturers are looking for alternative techniques that can support the need for a more innovative, flexible, and sustainable production process. One such technique that is currently gaining a lot of momentum is Additive Manufacturing (AM). AM can achieve more complex structures and geometries which in turn makes it possible for highly customised designs with greater efficiency and sustainability. However, despite all the advantages of AM, adoption rates are still low compared to industry predictions, thus some challenges need to be addressed. This paper aims to study the implementation of metal additive manufacturing (MAM) by comparing literature with a real-world example, i.e., a case study at Saab, in an effort to answer the research question: Why adopt MAM; what are the challenges to a successful implementation of MAM; and how can they be overcome? The main theories that have been analysed in this study are Diffusion of Innovation (DOI), Technology-Organisation-Environment (TOE) and Change Management. Which are believed to be essential for understanding the implementation process of new technology.  The thesis follows a qualitative research approach where a single case study was carried out to be able to conduct a more in-depth analysis of the research topic.  In the case study it was identified that key challenges for Saab in implementing MAM are related to Knowledge gaps (both internal and external, partly due to immature technology); Organisational (structural and cultural) and Materials (qualification and standardisation) These key challenges, as identified in the interviews with Saab, match the challenges found in literature where they are described as Knowledge/technical know-how challenges, Organisational challenges, Integration challenges and Standardisation/qualification challenges. In conclusion, the reason to adopt MAM for the case company, a producer of parts with high requirements on functionality and optimization, is the strategic importance due to the technology enabling architectural innovation. The main challenges are related to the organisation and product development process, both in part due to knowledge challenges. In overcoming the challenges to the implementation, it is believed that increased internal and external collaboration is important as a way of generating and developing knowledge and at the same time using the resources more efficiently. Also, the need for re-designing the product development process to become cross-functional and include the whole system to enable architectural innovation.
79

Ecology Of Non-Breeding And Breeding Crested Caracaras (Caracara cheriway) In Florida

Dwyer, James F. 14 June 2010 (has links)
Like many species, Florida's population of Northern Crested Caracaras (Caracara cheriway, hereafter "caracara") is likely declining due to loss of breeding habitat. Consequently, management-oriented restrictions on landscape modification are applied where breeding occurs, but management rarely is extended beyond breeding areas. Focusing management on breeding areas can be effective if all caracaras occupy breeding areas, all breeding areas are detected, and no intermittent breeding occurs. Management may not operate as intended if any of these criteria are unmet. To explore this possibility, I investigated the movement, habitat, survival, and social biology of non-breeding caracaras. I also investigated long-term occupancy of breeding habitat, and factors contributing to detection of breeding. Non-breeding caracaras occupy areas much larger than individual breeding territories, particularly during breeding seasons. Pastures occupied by cattle were the most used habitat, but non-breeding caracaras also occupied habitats atypical of breeding areas. Specifically, citrus groves were occupied extensively, and row crops were used particularly during breeding seasons. Non-breeding caracaras also shared communal roosts, sometimes with hundreds of conspecifics, and roosts were occupied year-round. Survival of non-breeding caracaras was lowest during breeding seasons. Adult non-breeding caracaras persisted in groups for multiple years without establishing breeding territories. This implies that breeding habitat is limited and saturated. Given the proportion of adults in groups, adults also were the first to find carrion more often than expected. Apparently, young caracaras benefit from grouping by following adults. I found caracaras at all sampled breeding areas where nests were originally documented during the 1990s, and found nests at 83% of territories where nests likely existed. I also found that observer experience, visit start time, and weather affected the probability that a nest would be detected. Thus, not all caracaras occupy breeding areas, and not all breeding attempts are likely to be detected. Long-term occupancy of breeding areas should render annual verification of nesting unnecessary as a trigger for maintaining management actions. Rather management should persist even without confirmation of annual breeding. Caracara management also may be optimized through supporting the non-breeding population by maintaining a matrix of cattle pasture and citrus groves, particularly around roosts. / Ph. D.
80

Pro- and antiapoptotic events in Herpes simplex virus type 1 (HSV-1) infection of immature dendritic cells

Kather, Angela 13 February 2012 (has links)
Herpes simplex virus Typ 1 (HSV-1) ist ein humanpathogenes Virus der Familie Herpesviridae. Für eine erfolgreiche Virusreplikation besitzt HSV-1 mehrere Gene, die in den meisten infizierten Zelltypen Apoptose verhindern. Im Gegensatz dazu führt die HSV-1 Infektion eines zentralen Zelltyps des Immunsystems, den unreifen dendritischen Zellen (iDCs), zu Apoptose. Dies könnte ein Aspekt der HSV-1 Immunevasion sein. Bisher waren die Ursachen der Apoptose von HSV-1 infizierten iDCs unzureichend aufgeklärt. Es wurde jedoch gezeigt, dass das antiapoptotische zelluläre Protein c-FLIP in HSV-1 infizierten iDCs reduziert ist. In dieser Arbeit wurde die c-FLIP Menge in iDCs erstmalig mit Hilfe von RNA Interferenz erfolgreich reduziert. Dies bestätigte die Bedeutung von c-FLIP für die Lebensfähigkeit von iDCs. Folglich könnte auch die Reduktion der c-FLIP Menge nach HSV-1 Infektion iDCs für Apoptose empfindlich machen. Die HSV-1 induzierte c-FLIP Reduktion erfolgte in späten Stadien der Infektion, abhängig von der ordnungsgemäßen Expression viraler „early“ und „leaky late“ Gene. Sie fand nicht auf RNA Ebene statt und war unabhängig vom Proteasom und der Bindung an den „death inducing signaling complex“. Stattdessen wurde c-FLIP wahrscheinlich von einer viralen oder zellulären Protease abgebaut. In dieser Arbeit wurde erstmals gezeigt, dass zusätzlich zu Veränderungen im zellulären Apoptosesignalnetzwerk der Mangel an einem antiapoptotischen viralen Faktor zur Apoptose von HSV-1 infizierten iDCs beiträgt. Eine Microarray Analyse der HSV-1 Genexpression ergab, dass HSV-1 Latenz-assoziierte Transkripte (LATs) in apoptotischen iDCs signifikant geringer exprimiert waren als in nicht-apoptotischen epithelialen Zellen. LATs besitzen in Neuronen und epithelialen Zellen eine antiapoptotische Aktivität. Diese könnte den Mangel an c-FLIP kompensieren. Übereinstimmend mit dieser Hypothese induzierte eine HSV-1 LAT-Deletionsmutante mehr Apoptose in iDCs im Vergleich zum Wildtyp-Virus. / Herpes simplex virus type 1 (HSV-1) is a human pathogen which belongs to the family Herpesviridae. HSV-1 encodes several genes, which serve to efficiently prevent apoptosis in most infected cell types, thereby ensuring successful virus replication. In contrast, HSV-1 infection of one central cell type of the immune system, immature dendritic cells (iDCs), results in apoptosis. This could be one aspect of HSV-1 immunevasion. So far, the mechanisms underlying apoptosis of HSV-1 infected iDCs were poorly defined. However, it has been shown that the antiapoptotic cellular protein c-FLIP is reduced in HSV-1 infected iDCs. In this work, the amount of c-FLIP was for the first time successfully reduced in iDCs by RNA interference. This confirmed the importance of c-FLIP for viability of iDCs. Therefore, it is likely that c-FLIP reduction after HSV-1 infection also sensitizes iDCs to apoptosis. HSV-1 induced c-FLIP reduction occurred at late stages of infection and was dependent on proper expression of early and leaky late virus genes. Furthermore, it was not operative at the RNA level and was independent from the proteasome and binding to the death inducing signaling complex. Rather, c-FLIP was presumably degraded by a viral or cellular protease. In this work it was shown for the first time, that in addition to changes in the cellular apoptosis signaling network, the lack of one antiapoptotic viral factor contributes to apoptosis of HSV-1 infected iDCs. HSV-1 latency-associated transcripts (LATs) were significantly lower expressed in apoptotic iDCs compared to non-apoptotic epithelial cells, determined by microarray analysis of HSV-1 gene expression. It is known that in neurons and epithelial cells, LATs possess a potent antiapoptotic activity. This could compensate the lack of c-FLIP. Consistent with this hypothesis, a LAT deletion mutant of HSV-1 induced more apoptosis in iDCs compared to the respective wild type virus.

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