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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.
361

Effects of Mid-Rotation Release on Forest Structure, Wildlife Habitat, and Pine Yield

Cheynet, Kyla Ingeborg 17 December 1999 (has links)
The effects of two forms of mid-rotation release on thinned, fertilized loblolly pine (Pinus taeda L.) plantations in Virginia were examined: aerial imazapyr and basal triclopyr application. Imazapyr measurement plots were installed in nine Piedmont and twelve Coastal Plain plantations operationally released with imazapyr, and triclopyr measurement plots were installed within a controlled fertilization/release study spanning both regions. No differences in volume were detected following triclopyr release. All release dates combined, Piedmont released areas averaged 0.06 m3/tree (18%) greater than the control and Coastal Plain released areas averaged 0.05 m3/tree (14%) greater than the control. Reductions in hardwood basal area, stem density, and shrub stratum cover were observed for both forms of release. Reductions in shrub stratum richness and diversity were also documented for imazapyr release; however, trends indicate that richness and diversity, as well as stem density and shrub stratum cover, may recover to pre-treatment levels. Herbaceous vegetation was increased on triclopyr sites, which was reflected in an elevated turkey (Meleagris gallopavo sylvestris L.) food/brood index. Following imazapyr release, habitat suitability index (HSI) values for pine warblers (Dendroica pinus L.) and black-capped chickadees (Parus atricapillus L.) increased due to reductions in canopy hardwoods and increases in snags. Reduced shrub stratum density resulted in a lower bobwhite quail (Colinus virginianus L.) cover index on imazapyr-released areas. / Master of Science
362

Suplementação da população de bugios-pretos (Alouatta caraya) no campus da Universidade de São Paulo em Ribeirão Preto pela soltura de indivíduos cativos - estudo do comportamento / Supplementation of the population of black howler-monkey (Alouatta caraya) on the campus of campus of University of São Paulo in Ribeirão Preto for the release of captive individuals the study of behavior

Rossi, Marcelí Joele 09 September 2011 (has links)
O campus da Universidade de São Paulo em Ribeirão Preto consiste em uma área de 450 ha, caracterizada por um mosaico de remanescentes de mata e construções, sendo uma das maiores áreas verdes do município. Para suplementar a população de bugios-pretos (Alouatta caraya) existente no campus, este estudo realizou a soltura de um casal cativo. O grupo residente, composto por quatro bugios, foi rastreado seis dias por mês num período de seis meses para verificação da área de vida com finalidade de definir uma área para a soltura do casal. Um macho adulto e uma fêmea subadulta foram unidos em cativeiro no Parque Municipal Morro de São Bento. A formação do casal foi realizada em três fases (familiarização, junção e pós-junção) com gradativo aumento de aproximação. O padrão de atividades foi registrado pelo método de varredura a cada 5 minutos por 2 horas durante 10 dias (para cada fase). Os valores obtidos ficaram próximos ao relatado para o gênero, com aumento do comportamento social no decorrer das fases: 4,4 16 e 35,2% (p<0,001). O casal foi transferido para um cativeiro na área de soltura, onde permaneceu por 44 dias. Neste período foi realizada a avaliação pré-soltura e a reeducação alimentar. Na avaliação pré-soltura foi verificado que a mudança de área não afetou significativamente o comportamento social do casal, cujo valor obtido foi de 29% (p=0,083 em comparação com o valor obtido na última fase da formação do casal). Na reeducação alimentar, gradativamente a dieta inicial de 2000 g de frutas por dia, teve 1200 g substituídas por folhas de cinco espécies vegetais. A soltura do casal foi realizada no dia 10 de novembro de 2009. O casal foi acompanhado das 6 às 18 h, quatro dias por mês num período de um ano novembro/09 à outubro/10, com exceção de janeiro/10 com total de 528 h de observação. O padrão de atividades foi registrado pelo método de varredura a cada 20 minutos. Durante o ano, o casal dedicou 61,7% do tempo para descanso, 5,9% para locomoção não-direcional, 6,1% para locomoção direcional, 10,9% para alimentação e 15,4% para comportamento social. A locomoção direcional, comportamento que melhor expressa a exploração da área, teve os registros de cada mês comparados com sua média anual (18,6). Os meses dezembro, fevereiro e março apresentaram registros acima da média, sendo o mês de dezembro significativamente maior (p<0,001). Os meses maio, junho, julho, agosto, setembro e outubro, apresentaram registros menores, sendo o mês de julho significativamente menor (p=0,032). A alimentação foi registrada pelo método 1-0 a cada 5 minutos. Durante o ano, o casal utilizou 146 indivíduos (árvores e lianas) de 38 espécies pertencentes a 18 famílias. As seis espécies mais consumidas correspondem a 61,3% do total de registros: Maclura tinctoria (14,8%), Leucaena leucocephala (13,3%), Ficus insipida (11,8%), Handroanthus impetiginosus (7,6%), Poincianella pluviosa (7%) e Terminalia catappa (6,8%). O total de espécies consumidas em cada mês foi comparado com a média anual de 9,8. Os meses de dezembro, fevereiro, março, abril e maio apresentaram mais espécies consumidas que a média. Os meses junho, julho, agosto, setembro e outubro apresentaram menos espécies que a média, sendo o mês de julho significativamente menor (p=0,033). A área de vida foi registrada pelo método de varredura a cada 1 hora. Durante o ano, o casal utilizou 50 quadrantes de 50 x 50 m (0,25 ha), totalizando uma área de 12,5 ha. O total de quadrantes utilizados por mês foi comparado com a média anual de 9. Os meses de dezembro, fevereiro e março apresentaram maior quantidade de quadrantes utilizados que a média, sendo os meses de dezembro e março significativamente maiores (p=0,039 e p=0,025). Os meses junho, julho, agosto, setembro e outubro apresentaram menor quantidade de quadrantes utilizados que a média. Foram encontradas duas áreas centrais (utilização > 10%), ambas correspondem à localização dos recursos alimentares mais utilizados e bambuzais altos e densos utilizados como árvores-dormitório. Com esses resultados, foi possível verificar que o casal explorou a área desconhecida até o 5° - 6° mês de soltura. A partir daí, espécies vegetais e quadrantes foram selecionados, evidenciando que o casal se organizou para atingir o equilíbrio das suas necessidades energéticas. Portanto, podemos concluir que já no primeiro ano o casal de bugios se adaptou ao campus, pois garantiu sua sobrevivência. Com um ano e meio de soltura ocorreu o nascimento do primeiro filhote, acrescentado que, além da sobrevivência o casal também garantiu sua reprodução. / The University of São Paulo campus in Ribeirão Preto is an area of 450 hectares, characterized by a mosaic of forest remnants and buildings, one of the largest green areas of the city. For this study a captive couple of black howler monkeys (Alouatta caraya) was released to supplement the existing campus population. In order to define an area for the release of the couple the resident group, composed of four monkeys, was tracked six days per month for a period of six months to determine their home range adult male and a sub-adult female were united in captivity in the Municipal Park Morro de Sao Bento. The couple formation was accomplished in three phases (familiarization, junction and post-junction) with gradual proximity increase. The activity pattern was recorded using the scanning method, every 5 minutes for 2 hours for 10 days (for each phase). Recorded values were close to those reported for the genus, with increased social behavior during the phases: from 4.4 to 16 and 35.2% (p<0.001). The couple was moved to a cage at the release site, where they stayed for 44 days. During this time the pre-release assessment and rehabilitation diet were implemented. During the pre-release it was verified that the change of area did not significantly affect the social behavior of the couple, whose value was 29% (p = 0.083 compared with the value obtained in the last phase of formation the couple). In the rehabilitation diet, of the initial 2000 g of fruit per day, 1200 g were gradually replaced by leaves of five plant species. The couple was release on November 10, 2009. The couple was followed from 6 am to 18 pm, four days per month for a period of one year - November/09 to October/10, except January/10 - a total of 528 observation hours. The activity pattern was recorded by the scanning method every 20 minutes. During the year they spent 61.7% of the time at rest, 5.9% non-directional movement, 6.1%directional movement, 10.9% feeding and 15.4% in social behavior. The directional movement, behavior that best expresses the exploration of the area, monthly records were compared to the annual average (18.6). December, February and March had above-average results with the month of December significantly higher (p<0.001). May, June, July, August, September and October, showed lower results, with the month of July being significantly lower (p=0.032). The feeding was recorded by the method 1-0 every 5 minutes. During the year the couple used 146 individuals (trees and vines) of 38 species belonging to 18 families. The six most consumed species account for 61.3% of total records: Maclura tinctoria (14.8%), Leucaena leucocephala (13.3%), Ficus insipida (11.8%), Handroanthus impetiginosus (7.6%) Poincianella rainfall (7%) and Terminalia catappa (6.8%). The total number of species consumed in each month was compared with the annual average of 9.8. More species than average were consumed during the months of December, February, March, April and May. Fewer species than the average were consumed during the months of June, July, August, September and October, July was significantly lower (p=0.033). The home range was recorded by the scanning method every 1 hour. During the year the couple used 50 quadrants of 50 x 50 m (0.25 ha), totaling an area of 12.5 hectares. The total number of quadrants used per month was compared with the annual average of 9. The months of December, February and March had a higher number of quadrants that the medium used, with December and March significantly higher (p=0.039 and p=0.025). June, July, August, September and October had fewer quadrants used than average. We found two core areas (use > 10%), both correspond to the most used food resources locations and dense tall bamboo ares used as dormitory trees. The results showed that the couple had explored the new area by the 5th - 6th month of release. Thereafter, plant species and quadrants were selected, showing that the couple had organized itself to balance its Therefore, we conclude that in the first year the couple adapted to the campus, ensuring its survival. After a year and a half of release the birth of first infant occurred. Thus, beyond survival, the couple also assured its reproduction.
363

Controlled drug release from oriented biodegradable polymers

Ambardekar, Rohan January 2015 (has links)
This research is the first systematic investigation of solid-state orientation as a novel method for controlling drug release from biodegradable polymers. The effect of various degrees of polymer orientation was studied in oriented Poly (L-lactic acid) (PLA) films containing curcumin and theophylline as model drugs. Additionally, direction specific drug release was studied from oriented PLA rods containing paracetamol. The films oriented to 2X uniaxial constant width (UCW) or 2X2Y biaxial draw ratio showed retardation of drug release, when their nematic structure was stabilised by the presence of crystalline theophylline. Contrarily, the same films when contained solid solution of curcumin, shrunk in the release medium and exhibited a release profile similar to the un-oriented films. All films oriented to the UCW draw ratio ≥ 3X contained α crystalline form of PLA and showed acceleration of drug release proportionate to the draw ratio. According to the proposed mechanism augmented formation of water filled channels in these films was responsible for faster drug release. Similarly, the paracetamol loaded PLA rods die-drawn to uniaxial draw ratios ≥ 3X exhibited enhancement of drug release. Importantly, the amount of drug released along the oriented chain axis was significantly larger than that in the perpendicular direction. Drug release from the die-drawn rods was accelerated by a greater degree than that observed from the oriented films. This can be correlated to the differences in their size, geometry and the crystalline form of PLA. In conclusion, the current study provided substantial evidence that solid-state orientation can offer a control over drug release from PLA.
364

Ritmicidade da emissão de propágulos em Chthamalus bisinuatus (Pilsbry, 1916): componentes endógenas e exógenas / Propagule emission rhythm in Chthamalus bisinuatus: endogenous and exogenous components.

Kasten, Paula 18 November 2011 (has links)
A sincronização reprodutiva em invertebrados marinhos é comum, e organismos do entremarés se valem de pistas exógenas, como os ciclos ambientais gerados pelos movimentos da Terra e da Lua, na sincronização de uma componente endógena que colocará em fase pelo menos uma etapa do ciclo reprodutivo. Em estudos anteriores com cracas, notou-se uma clara relação entre emissão larval e elevada produção fitoplanctônica, enquanto outros apontam uma estrita relação com os regimes de maré e fases da lua. Neste projeto pretendeu-se detectar as variáveis ambientais associadas à ritmicidade da emissão naupliar na craca Chthamalus bisinuatus em condições constantes de laboratório, permitindo, então, a detecção de uma componente endógena associada a tal atividade e acompanhar a mesma atividade em campo, podendo associar quais condições ambientais em tempo real influenciam essa etapa do ciclo reprodutivo. Para esses objetivos, populações foram submetidas a testes em condições constantes de laboratório, sendo as variáveis temperatura, fotoperíodo e tempo de imersão testados isoladamente e conjugados dois a dois. Em campo, populações do cirripédio tiveram monitoradas por um período de 32 dias, durante o qual a atividade de emissão larval, e as variáveis temperatura, fluxo de água e concentração de clorofila-a foram medidas a fim de se estabelecer uma relação entre as emissões e tais variáveis. Os resultados indicam a existência de uma componente endógena marcando o ritmo de emissão larval e da atividade de muda sincronizada com o ciclo de amplitude de maré (14.4 dias), bem como um papel relevante da ação sinérgica da oscilação ultradiana da altura da maré e da temperatura como modulador da sincronização de tais atividades. Em campo, os eventos extremos de temperatura, a concentração de clorofila-a (um indicador da disponibilidade de alimentos para os adultos) e o fluxo de água atuaram como indutores da emissão larval em um intervalo antecedente de 1 e 6 dias para as duas primeiras variáveis, e um intervalo de 1 a 3 dias posteriores para a última variável, provando, então, serem importantes na determinação do momento da emissão larval. Portanto, se conclui que ritmos endógenos associados à amplitude de maré podem explicar parcialmente o padrão circa semilunar centrado nos períodos de quadratura examinados em outras populações, mas, como é mostrado aqui, tal ritmicidade pode ser interrompida por variações de temperatura, disponibilidade de alimento e intenso fluxo de água. Discute-se que o primeiro efeito pode estar relacionado a mecanismos fisiológicos que garantem a reprodução de indivíduos submetidos a maiores riscos de mortalidade, e que a alimentação é um recurso limitante para a reprodução da população estudada. Em uma escala temporal menor, a ritmicidade endógena, sincronizada pela combinação de temperatura e tempo de imersão, favorece a emissão larval em períodos de maré-alta. Na ausência de outros fatores ambientais que controlam a emissão, uma componente endógena permitirá a emissão larval nos momentos de maré-alta dos períodos de quadratura, o que promoveria a retenção na linha de costa e minimizaria o risco de encalhe. / Synchronized reproduction is common among marine invertebrates, and intertidal organisms make use of exogenous cues, such as environmental cycles generated by the movements of the Earth and Moon, to synchronize their biological clocks in phase with such oscillations, at least in one stage of the reproductive cycle. In previous reports on barnacle rhythms, some studies have stressed a clear relationship between larval emission and high phytoplankton production, while others indicate a close relationship with the regimes of tide and moon phases. In this project we intended to detect environmental variables associated with the rhythmic larval release activity in the barnacle Chthamalus bisinuatus, both in constant laboratory conditions, allowing the detection of an endogenous component associated with such activity, and in the field, by monitoring larval release and other environmental conditions that might influence the reproductive cycle. For such purposes, populations were tested in constant laboratory conditions, where the variables temperature, photoperiod and time of immersion were tested both alone and combined in pairs, and in the field, by monitoring reproductive activity in populations of these cirripedes for 32 days, together with temperature, water flow, and chlorophyll-a concentration, as to establish relationships between larval release and these variables. The results indicate the existence of an endogenous component setting the rhythm of emission and larval molt activity synchronized with the cycle of tidal range (14.4 days), and the use of tides and daily fluctuations in temperature as cues in the synchronization of ultradian release activities. In the field, extremes of temperature, peaks of chlorophyll-a concentration (a proxy of food availability for adults) and water flow, triggered naupliar release 1 and 6 days ahead, for the first two variables, and 1 and 3 days before for the last one, thus proving to be important variables in determining the time of larval emission. Therefore, it is concluded that endogenous tidal-amplitude rhythms may partly explain sharp fortnight patterns centered at neap-tide periods in populations examined elsewhere, but, as shown herein, such rhythmicity may be disrupted by variations of temperature, food availability and intense water flow. It is argued that the first effect may be related to a physiological mechanism ensuring reproduction in individuals at a higher mortality risk, and that food is a limiting resource for reproduction in the study population. In a shorter time scale, endogenous rhythmicity, entrained by the combined control of temperature and immersion time, favors high-tide larval release. In the absence of other environmental release-inducing factors, endogenous timing would lead to high-tide release during neap periods, which would favor coastal retention and minimize stranding risk.
365

Light-Triggered Release of DNA from Plasmon-Resonant Nanoparticles

Huschka, Ryan 05 June 2013 (has links)
Plasmon-resonant nanoparticle complexes show promising potential for light-triggered, controllable delivery of deoxyribonucleic acids (DNA) for research and therapeutic purposes. For example, the approach of RNA interference (RNAi) ‒ using antisense DNA or RNA oligonucleotides to silence activity of a specific pathogenic gene transcript and reduce expression of the encoded protein ‒ is very useful in dissecting genetic function and holds promise as a molecular therapeutic. Herein, we investigate the mechanism and probe the in vitro therapeutic potential of DNA light-triggered release from plasmonic nanoparticles. First, we investigate the mechanism of light-triggered release by dehybridizing double-stranded (dsDNA) via laser illumination from two types of nanoparticle substrates: gold (Au) nanoshells and Au nanorods. Both light-triggered and thermally induced releases are distinctly observable from nanoshell-based complexes. Surprisingly, no analogous measurable light-triggered release was observable from nanorod-based complexes below the DNA melting temperature. These results suggest that a nonthermal mechanism may play a role in light-triggered DNA release. Second, we demonstrate the in vitro light-triggered release of molecules non-covalently attached within dsDNA bound to the Au nanoshell surface. DAPI (4',6-diamidino-2-phenylindole), a bright blue fluorescent molecule that binds reversibly to double-stranded DNA, was chosen to visualize this intracellular light-induced release process. Illumination through the cell membrane of the nanoshell-dsDNA-DAPI complexes dehybridizes the DNA and releases the DAPI molecules within living cells. The DAPI molecules diffuse to the nucleus and associate with the cell’s endogenous DNA. This work could have future applications towards drug delivery of molecules that associate with dsDNA. Finally, we demonstrate an engineered Au nanoshell (AuNS)-based therapeutic oligonucleotide delivery vehicle, designed to release its cargo on demand upon illumination with a near-infrared (NIR) laser. A poly(L)lysine peptide (PLL) epilayer coated onto the AuNS surface (AuNS-PLL) is used to capture intact, single-stranded antisense DNA oligonucleotide, or alternatively, double-stranded short-interfering RNA (siRNA) molecules. A green fluorescent protein (GFP)-expressing human lung cancer H1299 cell line was used to determine cellular uptake and GFP gene silencing mediated by AuNS-PLL delivery vector. The light-triggered release of oligonucleotides could have broad applications in the study of cellular processes and in the development of intracellular targeted therapies.
366

The Influence of Release Modality on Synaptic Transmission at a Developing Central Synapse

Fedchyshyn, Michael John 22 March 2010 (has links)
The auditory brainstem is comprised of a number of synapses specialized for the transmission of high-fidelity synaptic signals. Within the first three postnatal weeks, these pathways acquire the ability to process high-frequency signals without compromising timing information. However, little is known regarding developmental adaptations which confer this ability. Situated in the sound localization pathway, the calyx of Held-medial nucleus of the trapezoid body synapse provides an ideal model for investigating such adaptations as both the pre- and postsynaptic neurons are accessible to electrophysiological experimentation. Using this synapse, we have shown herein that the spatial coupling between voltage-gated calcium channels (VGCCs) and synaptic vesicles (SVs) tightens during development. Immature synapses use a loosely-coupled arrangement of many N- and P/Q-type VGCCs (“microdomain” modality) while mature synapses use a tightly-coupled arrangement of fewer P/Q-type VGCCs, to release SVs (“nanodomain” modality). As a consequence of this tightening, synaptic delay (SD) shortens. By fluorescence- and electron microscopy of SVs near active zones, we further identified the filamentous protein septin 5 as a molecular substrate, differentiating the two release modalities, which may act as a spatial barrier separating VGCCs and SVs in immature synapses. Finally, we have demonstrated that changes in release modality affect the nature of short-term plasticity observed at this synapse. Using trains of action potentials as presynaptic voltage-commands, we showed that, downstream of calcium influx, the microdomain modality promotes short-term facilitation in excitatory postsynaptic currents (IEPSC), and calcium-dependent decreases in SD, with these being absent in synapses employing the nanodomain modality. In contrast, we found that as a result of depletion of SVs, short-term depression of IEPSC dominates in synapses using the nanodomain modality, and correlates with calcium-dependent increases in SD. These findings imply that the type of release modality has a significant impact on the strength and timing of synaptic responses. The microdomain modality imparts greater dynamic range in timing and strength, but does so at the cost of efficiency and fidelity, while the nanodomain modality is a key accomplishment consolidating the high-fidelity abilities of this synapse.
367

The Influence of Release Modality on Synaptic Transmission at a Developing Central Synapse

Fedchyshyn, Michael John 22 March 2010 (has links)
The auditory brainstem is comprised of a number of synapses specialized for the transmission of high-fidelity synaptic signals. Within the first three postnatal weeks, these pathways acquire the ability to process high-frequency signals without compromising timing information. However, little is known regarding developmental adaptations which confer this ability. Situated in the sound localization pathway, the calyx of Held-medial nucleus of the trapezoid body synapse provides an ideal model for investigating such adaptations as both the pre- and postsynaptic neurons are accessible to electrophysiological experimentation. Using this synapse, we have shown herein that the spatial coupling between voltage-gated calcium channels (VGCCs) and synaptic vesicles (SVs) tightens during development. Immature synapses use a loosely-coupled arrangement of many N- and P/Q-type VGCCs (“microdomain” modality) while mature synapses use a tightly-coupled arrangement of fewer P/Q-type VGCCs, to release SVs (“nanodomain” modality). As a consequence of this tightening, synaptic delay (SD) shortens. By fluorescence- and electron microscopy of SVs near active zones, we further identified the filamentous protein septin 5 as a molecular substrate, differentiating the two release modalities, which may act as a spatial barrier separating VGCCs and SVs in immature synapses. Finally, we have demonstrated that changes in release modality affect the nature of short-term plasticity observed at this synapse. Using trains of action potentials as presynaptic voltage-commands, we showed that, downstream of calcium influx, the microdomain modality promotes short-term facilitation in excitatory postsynaptic currents (IEPSC), and calcium-dependent decreases in SD, with these being absent in synapses employing the nanodomain modality. In contrast, we found that as a result of depletion of SVs, short-term depression of IEPSC dominates in synapses using the nanodomain modality, and correlates with calcium-dependent increases in SD. These findings imply that the type of release modality has a significant impact on the strength and timing of synaptic responses. The microdomain modality imparts greater dynamic range in timing and strength, but does so at the cost of efficiency and fidelity, while the nanodomain modality is a key accomplishment consolidating the high-fidelity abilities of this synapse.
368

Mitochondrial gene expression in trypanosomatids

PROCHÁZKOVÁ, Michaela January 2018 (has links)
This thesis comprises of diverse projects all focused towards analysis of mitochondrial translation in unicellular parasites. As only two mitochondrially encoded genes are required during the life cycle stage when Trypanosoma brucei resides in the bloodstream of a mammalian host, this protist provides a simplified background in which to study mitochondrial translation termination phase. The leading project utilizes T. brucei to examine mitochondrial translation termination factor TbMrf1 by gene knockout. Subsequently, it is suggested that the peptidyl-tRNA hydrolase TbPth4 is able to abate the TbMrf1 knockout phenotype by its ability to rescue mitoribosomes that become stalled when TbMrf1 is absent. Additionally, modifying methyltransferase of TbMrf1, the TbMTQ1, was characterized. And finally, this work contributed to the development of the protein expression regulation method in Leishmania parasites, a protocol for measurement of proton pumping activity of FoF1 ATPase complex in native mitochondria, and optimization of purification protocol for hydrophobic recombinant proteins.
369

Suplementação da população de bugios-pretos (Alouatta caraya) no campus da Universidade de São Paulo em Ribeirão Preto pela soltura de indivíduos cativos - estudo do comportamento / Supplementation of the population of black howler-monkey (Alouatta caraya) on the campus of campus of University of São Paulo in Ribeirão Preto for the release of captive individuals the study of behavior

Marcelí Joele Rossi 09 September 2011 (has links)
O campus da Universidade de São Paulo em Ribeirão Preto consiste em uma área de 450 ha, caracterizada por um mosaico de remanescentes de mata e construções, sendo uma das maiores áreas verdes do município. Para suplementar a população de bugios-pretos (Alouatta caraya) existente no campus, este estudo realizou a soltura de um casal cativo. O grupo residente, composto por quatro bugios, foi rastreado seis dias por mês num período de seis meses para verificação da área de vida com finalidade de definir uma área para a soltura do casal. Um macho adulto e uma fêmea subadulta foram unidos em cativeiro no Parque Municipal Morro de São Bento. A formação do casal foi realizada em três fases (familiarização, junção e pós-junção) com gradativo aumento de aproximação. O padrão de atividades foi registrado pelo método de varredura a cada 5 minutos por 2 horas durante 10 dias (para cada fase). Os valores obtidos ficaram próximos ao relatado para o gênero, com aumento do comportamento social no decorrer das fases: 4,4 16 e 35,2% (p<0,001). O casal foi transferido para um cativeiro na área de soltura, onde permaneceu por 44 dias. Neste período foi realizada a avaliação pré-soltura e a reeducação alimentar. Na avaliação pré-soltura foi verificado que a mudança de área não afetou significativamente o comportamento social do casal, cujo valor obtido foi de 29% (p=0,083 em comparação com o valor obtido na última fase da formação do casal). Na reeducação alimentar, gradativamente a dieta inicial de 2000 g de frutas por dia, teve 1200 g substituídas por folhas de cinco espécies vegetais. A soltura do casal foi realizada no dia 10 de novembro de 2009. O casal foi acompanhado das 6 às 18 h, quatro dias por mês num período de um ano novembro/09 à outubro/10, com exceção de janeiro/10 com total de 528 h de observação. O padrão de atividades foi registrado pelo método de varredura a cada 20 minutos. Durante o ano, o casal dedicou 61,7% do tempo para descanso, 5,9% para locomoção não-direcional, 6,1% para locomoção direcional, 10,9% para alimentação e 15,4% para comportamento social. A locomoção direcional, comportamento que melhor expressa a exploração da área, teve os registros de cada mês comparados com sua média anual (18,6). Os meses dezembro, fevereiro e março apresentaram registros acima da média, sendo o mês de dezembro significativamente maior (p<0,001). Os meses maio, junho, julho, agosto, setembro e outubro, apresentaram registros menores, sendo o mês de julho significativamente menor (p=0,032). A alimentação foi registrada pelo método 1-0 a cada 5 minutos. Durante o ano, o casal utilizou 146 indivíduos (árvores e lianas) de 38 espécies pertencentes a 18 famílias. As seis espécies mais consumidas correspondem a 61,3% do total de registros: Maclura tinctoria (14,8%), Leucaena leucocephala (13,3%), Ficus insipida (11,8%), Handroanthus impetiginosus (7,6%), Poincianella pluviosa (7%) e Terminalia catappa (6,8%). O total de espécies consumidas em cada mês foi comparado com a média anual de 9,8. Os meses de dezembro, fevereiro, março, abril e maio apresentaram mais espécies consumidas que a média. Os meses junho, julho, agosto, setembro e outubro apresentaram menos espécies que a média, sendo o mês de julho significativamente menor (p=0,033). A área de vida foi registrada pelo método de varredura a cada 1 hora. Durante o ano, o casal utilizou 50 quadrantes de 50 x 50 m (0,25 ha), totalizando uma área de 12,5 ha. O total de quadrantes utilizados por mês foi comparado com a média anual de 9. Os meses de dezembro, fevereiro e março apresentaram maior quantidade de quadrantes utilizados que a média, sendo os meses de dezembro e março significativamente maiores (p=0,039 e p=0,025). Os meses junho, julho, agosto, setembro e outubro apresentaram menor quantidade de quadrantes utilizados que a média. Foram encontradas duas áreas centrais (utilização > 10%), ambas correspondem à localização dos recursos alimentares mais utilizados e bambuzais altos e densos utilizados como árvores-dormitório. Com esses resultados, foi possível verificar que o casal explorou a área desconhecida até o 5° - 6° mês de soltura. A partir daí, espécies vegetais e quadrantes foram selecionados, evidenciando que o casal se organizou para atingir o equilíbrio das suas necessidades energéticas. Portanto, podemos concluir que já no primeiro ano o casal de bugios se adaptou ao campus, pois garantiu sua sobrevivência. Com um ano e meio de soltura ocorreu o nascimento do primeiro filhote, acrescentado que, além da sobrevivência o casal também garantiu sua reprodução. / The University of São Paulo campus in Ribeirão Preto is an area of 450 hectares, characterized by a mosaic of forest remnants and buildings, one of the largest green areas of the city. For this study a captive couple of black howler monkeys (Alouatta caraya) was released to supplement the existing campus population. In order to define an area for the release of the couple the resident group, composed of four monkeys, was tracked six days per month for a period of six months to determine their home range adult male and a sub-adult female were united in captivity in the Municipal Park Morro de Sao Bento. The couple formation was accomplished in three phases (familiarization, junction and post-junction) with gradual proximity increase. The activity pattern was recorded using the scanning method, every 5 minutes for 2 hours for 10 days (for each phase). Recorded values were close to those reported for the genus, with increased social behavior during the phases: from 4.4 to 16 and 35.2% (p<0.001). The couple was moved to a cage at the release site, where they stayed for 44 days. During this time the pre-release assessment and rehabilitation diet were implemented. During the pre-release it was verified that the change of area did not significantly affect the social behavior of the couple, whose value was 29% (p = 0.083 compared with the value obtained in the last phase of formation the couple). In the rehabilitation diet, of the initial 2000 g of fruit per day, 1200 g were gradually replaced by leaves of five plant species. The couple was release on November 10, 2009. The couple was followed from 6 am to 18 pm, four days per month for a period of one year - November/09 to October/10, except January/10 - a total of 528 observation hours. The activity pattern was recorded by the scanning method every 20 minutes. During the year they spent 61.7% of the time at rest, 5.9% non-directional movement, 6.1%directional movement, 10.9% feeding and 15.4% in social behavior. The directional movement, behavior that best expresses the exploration of the area, monthly records were compared to the annual average (18.6). December, February and March had above-average results with the month of December significantly higher (p<0.001). May, June, July, August, September and October, showed lower results, with the month of July being significantly lower (p=0.032). The feeding was recorded by the method 1-0 every 5 minutes. During the year the couple used 146 individuals (trees and vines) of 38 species belonging to 18 families. The six most consumed species account for 61.3% of total records: Maclura tinctoria (14.8%), Leucaena leucocephala (13.3%), Ficus insipida (11.8%), Handroanthus impetiginosus (7.6%) Poincianella rainfall (7%) and Terminalia catappa (6.8%). The total number of species consumed in each month was compared with the annual average of 9.8. More species than average were consumed during the months of December, February, March, April and May. Fewer species than the average were consumed during the months of June, July, August, September and October, July was significantly lower (p=0.033). The home range was recorded by the scanning method every 1 hour. During the year the couple used 50 quadrants of 50 x 50 m (0.25 ha), totaling an area of 12.5 hectares. The total number of quadrants used per month was compared with the annual average of 9. The months of December, February and March had a higher number of quadrants that the medium used, with December and March significantly higher (p=0.039 and p=0.025). June, July, August, September and October had fewer quadrants used than average. We found two core areas (use > 10%), both correspond to the most used food resources locations and dense tall bamboo ares used as dormitory trees. The results showed that the couple had explored the new area by the 5th - 6th month of release. Thereafter, plant species and quadrants were selected, showing that the couple had organized itself to balance its Therefore, we conclude that in the first year the couple adapted to the campus, ensuring its survival. After a year and a half of release the birth of first infant occurred. Thus, beyond survival, the couple also assured its reproduction.
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Ritmicidade da emissão de propágulos em Chthamalus bisinuatus (Pilsbry, 1916): componentes endógenas e exógenas / Propagule emission rhythm in Chthamalus bisinuatus: endogenous and exogenous components.

Paula Kasten 18 November 2011 (has links)
A sincronização reprodutiva em invertebrados marinhos é comum, e organismos do entremarés se valem de pistas exógenas, como os ciclos ambientais gerados pelos movimentos da Terra e da Lua, na sincronização de uma componente endógena que colocará em fase pelo menos uma etapa do ciclo reprodutivo. Em estudos anteriores com cracas, notou-se uma clara relação entre emissão larval e elevada produção fitoplanctônica, enquanto outros apontam uma estrita relação com os regimes de maré e fases da lua. Neste projeto pretendeu-se detectar as variáveis ambientais associadas à ritmicidade da emissão naupliar na craca Chthamalus bisinuatus em condições constantes de laboratório, permitindo, então, a detecção de uma componente endógena associada a tal atividade e acompanhar a mesma atividade em campo, podendo associar quais condições ambientais em tempo real influenciam essa etapa do ciclo reprodutivo. Para esses objetivos, populações foram submetidas a testes em condições constantes de laboratório, sendo as variáveis temperatura, fotoperíodo e tempo de imersão testados isoladamente e conjugados dois a dois. Em campo, populações do cirripédio tiveram monitoradas por um período de 32 dias, durante o qual a atividade de emissão larval, e as variáveis temperatura, fluxo de água e concentração de clorofila-a foram medidas a fim de se estabelecer uma relação entre as emissões e tais variáveis. Os resultados indicam a existência de uma componente endógena marcando o ritmo de emissão larval e da atividade de muda sincronizada com o ciclo de amplitude de maré (14.4 dias), bem como um papel relevante da ação sinérgica da oscilação ultradiana da altura da maré e da temperatura como modulador da sincronização de tais atividades. Em campo, os eventos extremos de temperatura, a concentração de clorofila-a (um indicador da disponibilidade de alimentos para os adultos) e o fluxo de água atuaram como indutores da emissão larval em um intervalo antecedente de 1 e 6 dias para as duas primeiras variáveis, e um intervalo de 1 a 3 dias posteriores para a última variável, provando, então, serem importantes na determinação do momento da emissão larval. Portanto, se conclui que ritmos endógenos associados à amplitude de maré podem explicar parcialmente o padrão circa semilunar centrado nos períodos de quadratura examinados em outras populações, mas, como é mostrado aqui, tal ritmicidade pode ser interrompida por variações de temperatura, disponibilidade de alimento e intenso fluxo de água. Discute-se que o primeiro efeito pode estar relacionado a mecanismos fisiológicos que garantem a reprodução de indivíduos submetidos a maiores riscos de mortalidade, e que a alimentação é um recurso limitante para a reprodução da população estudada. Em uma escala temporal menor, a ritmicidade endógena, sincronizada pela combinação de temperatura e tempo de imersão, favorece a emissão larval em períodos de maré-alta. Na ausência de outros fatores ambientais que controlam a emissão, uma componente endógena permitirá a emissão larval nos momentos de maré-alta dos períodos de quadratura, o que promoveria a retenção na linha de costa e minimizaria o risco de encalhe. / Synchronized reproduction is common among marine invertebrates, and intertidal organisms make use of exogenous cues, such as environmental cycles generated by the movements of the Earth and Moon, to synchronize their biological clocks in phase with such oscillations, at least in one stage of the reproductive cycle. In previous reports on barnacle rhythms, some studies have stressed a clear relationship between larval emission and high phytoplankton production, while others indicate a close relationship with the regimes of tide and moon phases. In this project we intended to detect environmental variables associated with the rhythmic larval release activity in the barnacle Chthamalus bisinuatus, both in constant laboratory conditions, allowing the detection of an endogenous component associated with such activity, and in the field, by monitoring larval release and other environmental conditions that might influence the reproductive cycle. For such purposes, populations were tested in constant laboratory conditions, where the variables temperature, photoperiod and time of immersion were tested both alone and combined in pairs, and in the field, by monitoring reproductive activity in populations of these cirripedes for 32 days, together with temperature, water flow, and chlorophyll-a concentration, as to establish relationships between larval release and these variables. The results indicate the existence of an endogenous component setting the rhythm of emission and larval molt activity synchronized with the cycle of tidal range (14.4 days), and the use of tides and daily fluctuations in temperature as cues in the synchronization of ultradian release activities. In the field, extremes of temperature, peaks of chlorophyll-a concentration (a proxy of food availability for adults) and water flow, triggered naupliar release 1 and 6 days ahead, for the first two variables, and 1 and 3 days before for the last one, thus proving to be important variables in determining the time of larval emission. Therefore, it is concluded that endogenous tidal-amplitude rhythms may partly explain sharp fortnight patterns centered at neap-tide periods in populations examined elsewhere, but, as shown herein, such rhythmicity may be disrupted by variations of temperature, food availability and intense water flow. It is argued that the first effect may be related to a physiological mechanism ensuring reproduction in individuals at a higher mortality risk, and that food is a limiting resource for reproduction in the study population. In a shorter time scale, endogenous rhythmicity, entrained by the combined control of temperature and immersion time, favors high-tide larval release. In the absence of other environmental release-inducing factors, endogenous timing would lead to high-tide release during neap periods, which would favor coastal retention and minimize stranding risk.

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