Dissertations / Theses: 'Diel vertical'

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O'Malley, Brian Patrick. "Evaluation of Mysis partial diel vertical migration." ScholarWorks @ UVM, 2019. https://scholarworks.uvm.edu/graddis/996.

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Mass animal migrations represent large movements of biomass, energy, and nutrients with predictable patterns and important ecosystem-level consequences. Diel vertical migration (DVM) in aquatic systems, the daily movement of organisms from deeper depths during the day to shallower depths in the water column at night, is widespread in freshwater and marine systems. Recent studies, however, suggest partial migration behavior, whereby only some portion of a population migrates, is the rule rather than the exception in a range of migratory fauna, including those that undergo DVM. Hypotheses to explain why partial migrations occur complicate traditional views on DVM and challenge conventional theories. I address intraspecific variation in DVM behavior of an aquatic omnivore, Mysis diluviana, to test several long-standing assumptions about benthic-pelagic DVM in Mysis. I evaluated the extent of partial DVM and several potential drivers within a Lake Champlain Mysis population. I used traditional net-based field observations, a novel deep-water video camera system, and a laboratory experiment, to compare distributions, demographics, abundance estimates, hunger-satiation state, and feeding behavior, of migrant and non-migrant Mysis across multiple seasons, habitats, and different times of the day. Findings from my dissertation suggest Mysis partial DVM is common, and is associated with body size and demographic differences among individuals. Partial DVM behavior, however, did not correspond to strong differences in feeding preference or hunger-satiation state of individuals. My results contribute toward a more comprehensive understanding of migration theory and mysid biology, by including the often overlooked, but important, benthic habitat component of DVM studies, and fills in several ecological knowledge gaps regarding a key omnivore in many deep lake food webs across North America where Mysis serve as both predators and prey to many organisms.

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Jarvis, Toby. "The vertical export of carbon and nitrogen caused by zooplankton diel vertical migration." Thesis, Open University, 2003. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.272958.

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Dawdry, Nicola Elizabeth. "Diel vertical migration and feeding by krill Meganyctiphanes norvegica." Thesis, University of Plymouth, 2004. http://hdl.handle.net/10026.1/2602.

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The diel vertical migration (DVM) of zooplankton has been extensively studied and reviewed. Yet the controlling mechanisms for DVIVI are still uncertain, although several hypotheses, e. g. predator evasion, hunger - satiation, light avoidance, have been proposed. This is particularly so for krill. An important part of understanding krill DVM depends on explaining the factors which drive krill to the surface waters at night. It is frequently speculated that krill migrate to the surface layers to feed. Although there is a vast literature on krill feeding (and the pattern of krill DVM) there has been little attempt to establish the role of feeding in DVIVI. Consequently, the main aims of this thesis were to further explore the mechanisms for krill DVIVI and also to explain the feeding strategy of krill in order to understand the role of feeding in DVM, using Northern krill Meganyctiphanes norvegica as a model system. These aims were achieved by examining the following: whether krill are selective feeders and also whether the morphology of the feeding basket constrains the food types that can be handled by krill; whether krill feed throughout DVM; the relationship between krill metabolism and feeding during DVM. Krill showed significantly greater feeding rates with larger food types compared with smaller food types and this size selection appeared to be at least in part related to the morphology of the feeding basket. Above all it seemed that krill were opportunistic omnivores and the food types handled by krill were affected by the morphology of the feeding basket. Krill also showed significantly greater feeding rates when' offered food types available during the night compared with during the day. Gut contents from field caught individuals supported that krill did not feed extensively during the day as day caught individuals had significantly less stomach pigment content compared with night caught individuals. As krill appeared to not feed extensively on day time available food types it raised the question 'is there a cost to not feeding extensively during the day'. There did appear to be a cost to the lower daytime feeding than compared with the greater feeding shown both with night time available food types and from night captured individuals. It was hypothesized that krill may break down their respiratory pigment, haemocyanin (Hc) possibly for nutrition during these periods of low feeding during the day. In a field experiment, day captured krill had significantly lower Hc concentrations ([Hcl) than individuals captured at night. There was a clear cost to the lower [Hc] of day caught krill as concentrations of lactic acid in the haemolymph (indicating an 02 debt) were significantly greater in these day captured krill than compared with night captured krill. Consequently it seems that krill break down Hc during the day probably for nutrition because, for whatever reason, they do not feed extensively on the food types available to them in the deeper depths they reside within during the day. As they ascend to the surface layers at night, where they feed to significantly greater levels on the available food types, they appeared to rebuild their [Hc] and recover from the 02 debt they incurred during the day. Feeding experiments examining the recovery of [Hc] with food types available during either the day or night showed that after starvation krill recovered their [Hc] significantly quicker (and possibly to higher levels) with night available food types compared with day available food types. As they appear to be opportunistic omnivores it is proposed that this feeding strategy would facilitate the recovery of their daytime incurred debts. Krill appeared to show an asynchronously DVIVI and in particular female krill appeared to ascend to the surface layers of the water column earlier than males. In fact female krill showed a more extreme pattern of metabolism during DVIVI, with significantly greater [Hc] (ca. twice that of males) but also greater lactate debts with the breakdown of their Hc during the day. The earlier ascent to the surface layers and also the much greater [Hc] of females may indicate that they have greater metabolic demands than males. The asynchronous pattern of krill DVIVI supports the hunger - satiation hypothesis for DVM. If satiation is modified to also include the recovery of daytime incurred debts the findings of this thesis do indeed fit this hypothesis. A tentative model is proposed for krill DVM where krill break down their Hc during the day and then recover at night with feeding in the surface layers of the water column.

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Reichwaldt, Elke S. "The effects of diel vertical migration of Daphnia on zooplankton-phytoplankton interactions." Diss., lmu, 2004. http://nbn-resolving.de/urn:nbn:de:bvb:19-22075.

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Neverman, Darcy. "Diel Vertical Migration and Feeding of Underyearling Bear Lake Sculpin Cottus extensus (Pisces, Cottidae)." DigitalCommons@USU, 1989. https://digitalcommons.usu.edu/etd/4406.

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Underyearling Bear Lake sculpin exhibit a diel pattern of vertical migration throughout the pelagic region of Bear Lake (Utah-Idaho) until they are approximately 22 mm standard length. Individuals move from the bottom of the lake (5° C) during the day into the water column (13-16° C) at night. The migration, however, is not related to feeding. Although the dominant copepod in the water column, Epischura nevadensis, do undergo a similar diel vertical migration, stomach analysis of juvenile sculpin captured by trawling shows that they do not feed in the water column. Instead, from July through October, their diet is dominated (70-93%) by benthic copepods and ostracods. Also, gut fullness of sculpin increases through the daylight period and decreases through the night, reaching minimum levels just before the dawn descent. Furthermore, feeding trials conducted in the laboratory show that juvenile sculpin feed most efficiently at light intensities found on the bottom (30-60m) of Bear Lake during the day. Feeding rate coefficients increase markedly from 1013 photons m-2S-1 until peaking at intermediate intensities of 1016 photons m-2S-1 and then decline at higher light levels. Although they do not migrate to feed, the movement into the warmer water appears to increase the sculpin's digestion rate, thereby allowing continued feeding during the day. This supports the hypothesis that diel vertical migration in Bear Lake sculpin is a thermoregulatory strategy that increases growth rate.

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Dean, Cayla Whitney. "Biophysical Interactions in the Straits of Florida: Turbulent Mixing Due to Diel Vertical Migrations of Zooplankton." NSUWorks, 2014. http://nsuworks.nova.edu/occ_stuetd/14.

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Diel vertical migrations (DVM) comprise the largest animal migration on the planet and are a phenomenon present in all bodies of water on Earth. A strong sound scattering layer undergoing DVM was observed in the Straits of Florida via a bottom-mounted Acoustic Doppler current profiler (ADCP) Workhorse Longranger 75 kHz (Teledyne RD Instruments) located at the 244 m isobath. ADCP average backscatter showed a clear periodicity corresponding with sunrise and sunset times indicating the presence of a nocturnal DVM. Analysis of the ADCP backscatter data indicated zooplankton swimming velocities were faster during sunrise than sunset times. In several cases the zooplankton swimming velocity appeared to be faster at the beginning of the descent, after which the swimming velocity decreased. Analysis of ADCP velocity data indicated a measureable decrease in the northward component of the current velocity field during migrations (sunrise and sunset) compared to three hours prior. This was presumably associated with an increase in drag due to turbulent friction associated with DVM. A non-hydrostatic computational fluid dynamics (CFD) model with injection of Lagrangian particles was utilized to simulate the effects of DVM on the velocity field and turbulence signature of the Florida Current. A domain simulating a section of the Florida Current was created and zooplankton were represented by particle injection with a discrete phase model. The model was run with and without particles, holding all other parameters the same, for comparison. Idealized temperature stratification and velocity profiles were set for both summer and winter conditions to observe seasonal differences. For each case, velocity and turbulence with particles were compared to results without particles to confirm the changes in profiles were due to the zooplankton (Lagrangian particles). In several cases there was an observable change in average x-velocity profiles due to the injection of particles into the domain. In all cases there was an observable increase in subgrid turbulent viscosity in the wake of the injected particles. This effect was much stronger in the winter case, most likely due to stratification of the water column which gave a near critical Richardson number. These results indicated that DVM does in fact have an effect on the velocity profile and turbulence signature in a strong current under certain conditions and that there was a seasonal difference due to stratification profiles.

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Rabindranath, Ananda. "Investigations into temporal and spatial variability of zooplankton at the Svalbard archipelago." Thesis, University of St Andrews, 2013. http://hdl.handle.net/10023/3814.

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Plankton are generally considered good indicators for ocean climate variability, but plankton data from the Arctic are still comparatively scarce. Due to this scarcity of information, the prevalence of vertical migration behaviour at high latitude is still debated. Atlantic inflow is a key process governing biological diversity in the Arctic Ocean, and the location of the Svalbard archipelago makes it an ideal study area to monitor this inflow. Comparing the zooplankton community within the fjords of Svalbard at various latitudes allowed us to assess the influence of Atlantic inflow and any subsequent changes in zooplankton composition that may have implications for higher trophic levels. Using sediment traps deployed on oceanic moorings, Chapter 3 of this thesis analysed long term observations from sea-ice dominated Rijpfjorden for the first time, and compared the zooplankton to Atlantic Water influenced Kongsfjorden. Chapters 4 and 5 investigated the spatial relevance of our moored observations using shipboard observations, and chapters 6 and 7 present observations of vertical migration across a range of conditions. Kongsfjorden was dominated by Calanus copepods associated with Arctic and Atlantic water, and strongly influenced by Atlantic Water advection. Rijpfjorden was largely influenced by sea-ice formation with higher proportional abundances of macrozooplankton species. Advection brought Atlantic associated species into Rijpfjorden during warmer years. Prevailing hydrology and bathymetry were highlighted as factors forcing zooplankton distribution, while advection was identified as responsible for much of the observed small scale spatial variation amongst weaker swimmers. At an aggregation scale of 0.5 nautical miles, zooplankton distribution was highly patchy and moored observations could only be reliably expanded outwards to a maximum of 1 nautical mile. Low amplitude diel vertical migration (especially by younger copepodids) was identified in surface waters when a food source was available. These observations must be considered within the dynamic framework of advection highlighted by this thesis.

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Kramer, Eva Lauren. "Diel Vertical Distribution of Microcystis and Associated Environmental Factors in the Western Basin of Lake Erie." University of Toledo / OhioLINK, 2018. http://rave.ohiolink.edu/etdc/view?acc_num=toledo1544813640320216.

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Levy, David Alan. "The selective advantage of diel vertical migration behavior in juvenile sockeye salmon and kokanee (Oncorhynchus nerka)." Thesis, University of British Columbia, 1989. http://hdl.handle.net/2429/29178.

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The widespread occurrence of diel vertical migration behavior in pelagic aquatic organisms suggests that there is a selective advantage of the behavior compared to a static vertical depth distribution in the water column. Juvenile sockeye salmon (Oncorhynchus nerka) are active diel vertical migrators within pelagic lacustrine habitats, usually migrating over vertical distances covering tens of meters. The migrations are timed such that the animals occupy shallow depths during crepuscular and nocturnal periods, and spend daytime periods relatively deep in the water column. Hydroacoustic surveys were undertaken in fifteen British Columbia sockeye and kokanee lakes in order to compare predictions from selective advantage theories with the performance of the animals under field conditions. Juvenile sockeye undertook diel vertical migrations in all systems studied with the exception of Nimpkish Lake, where the migrations were periodically reversed, and Chilko Lake, where the migrations were periodically relaxed. None of the single factor theories correctly predicted all of the features of juvenile sockeye diel vertical migration. A multifactor theory, which interpreted the migration as a three-way compromise between foraging, predator avoidance, and the optimization of nocturnal metabolic efficiency, provided the most realistic explanation for the selective advantage of the behavior. The field observations also supported a hypothesized sensory mechanism for the behavior involving light and temperature controlling the day and night depth positions respectively. Two distinct kokanee diel migratory patterns were observed within Okanagan Lake. One group of animals migrated in a similar fashion as juvenile sockeye, while the second group undertook a reversed diel vertical migration. Target strength estimates from a high frequency echosounder suggested that small juveniles comprised the first group, while larger sub-adults comprised the second. The field observations are consistent with an ontogenetic shift in kokanee diel vertical migratory behavior within Okanagan Lake. Crustacean zooplankton prey organisms of juvenile sockeye maintained static diel vertical distributions within three Eraser River system sockeye lakes. Within Babine Lake, the cladoceran Bosmina coregoni undertook reversed diel vertical migrations probably in response to the vertical migrations undertaken by the predatory copepod Heterocope septentrionalis. Within Nimpkish Lake, where juvenile sockeye undertook reversed diel vertical migrations, B. coregoni as well as other planktonic Crustacea undertook diel vertical migrations. The correspondance between vertical migratory patterns in zooplankton and planktivores suggests a tight coupling in the diel migratory behavior of adjacent trophic levels with potentially important consequences for pelagic aquatic community structure.
Science, Faculty of
Zoology, Department of
Graduate

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Leach, Taylor Hepburn. "Cause and Consequences of Spatial Dynamics of Planktonic Organisms in Lake Ecosystems." Miami University / OhioLINK, 2016. http://rave.ohiolink.edu/etdc/view?acc_num=miami1479747973843758.

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Hänselmann, Kristin [Verfasser], and Axel [Akademischer Betreuer] Temming. "Diel Vertical Migration Patterns of Baltic Sea Copepods Analysed with a Video Plankton Recorder / Kristin Hänselmann ; Betreuer: Axel Temming." Hamburg : Staats- und Universitätsbibliothek Hamburg, 2019. http://d-nb.info/1198404248/34.

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Hänselmann, Kristin Verfasser], and Axel [Akademischer Betreuer] [Temming. "Diel Vertical Migration Patterns of Baltic Sea Copepods Analysed with a Video Plankton Recorder / Kristin Hänselmann ; Betreuer: Axel Temming." Hamburg : Staats- und Universitätsbibliothek Hamburg, 2019. http://d-nb.info/1198404248/34.

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Kaltenberg, Amanda May. "38-kHz ADCP investigation of deep scattering layers in sperm whale habitat in the northern Gulf of Mexico." Texas A&M University, 2004. http://hdl.handle.net/1969.1/1387.

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A hull-mounted 38-kHz phased-array acoustic Doppler current profiler (ADCP) was used to acoustically survey the continental margin of the northern Gulf of Mexico (GOM) during 6 cruises in 2002-2003. This is the first backscatter survey with a 38-kHz ADCP in the Gulf of Mexico. ADCPs have been used as a proxy to measure the volume backscatter return from plankton in the water column, however previous studies were restricted to the upper 200 to 300 meters due to the relatively high frequency of operation (150-300 kHz) of the transducers. In addition to measuring deep water current velocities, the 38-kHz phased-array ADCP can measure Relative Acoustic Backscatter Intensity (RABI) as deep as 1000 meters. The daytime depth of the main deep scattering layer at 400 to 500 meters was resolved, and locally high backscatter intensity can be seen down to 800 meters. The objectives were to determine how to analyze RABI from the instrument to resolve scattering layers, and then to seek secondary deep scattering layers of potential prey species below the main deep scattering layer, from 600 to 800 meters in the feeding range for Gulf of Mexico sperm whales. Based on RABI from the 38-kHz ADCP, secondary DSLs in sperm whale diving range were more commonly recorded over the continental shelf than in the deep basin region of the Gulf of Mexico. The daytime depths of migrating plankton showed variation depending on physical circulation features (cyclone, anticyclone, proximity to Mississippi river, and Loop Current) present. Vertical migrations compared between concurrently running 38 and 153-kHz ADCPs showed an overlap of acoustic scatterers recorded by the two instruments, however the 153-kHz instrument has much finer vertical resolution. Vertical migration rates were calculated and simultaneous net tow samples from one of the cruises was used to compare abundance estimates by the two methods.

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Giron, Aline Karen Santana. "Variaçãos sazonal e migração vertical da comunidade zooplanctônica (exceto Rotifera) do reservatório de Itupararanga, Votorantim, SP." Universidade Federal de São Carlos, 2013. https://repositorio.ufscar.br/handle/ufscar/1528.

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The present study aimed to analyse the Itupararanga reservoir zooplankton community in relation to diel and seasonal variation and vertical migration of the organisms in the water column and verify if there are patterns of variation. For this two samples were performed in the reservoir in 2011: in February, rainy period and in july, dry period. The collections were performed in diel cycle (every four hours), in three different layers of the water column (surface, middle and bottom) and in two environments of the reservoir (dam and central body). Stratification in the water column was observed for both environments and both periods. 25 species of the mesozooplankton were identified. Chaoborus larvae were more abundant in February in relation to july and the opposite was observed for cladocerans and copepods. Among the copepods, dominance of juvenile stages (nauplii and copepodites) was observed in both environments and periods. Among the adults of copepods the specie more abundant was Notodiaptomus deitersi (1.298 org.m3) and among the cladocerans was Bosmina freyi (32.282 org.m3). The peak of the total density of the zooplankton community occurred during the dry period in the dam environment with 81.211 org.m3. Chaoborus exercised predation pressure on microcrustaceans during the rainy period. During the dry period, in the absence of Chaoborus in the water column, cladocerans and copepods were more ecologically successful. For all of the groups was observed the usual pattern of vertical migration; reverse migration was not observed. Despite predation pressure, the microcrustaceans not altered their vertical distribution for decrease special overlap with Chaoborus. For all of the groups the migration pattern adopted seems a result of escape from predators and search for good food resources.
O presente estudo teve como objetivo analisar a comunidade zooplanctônica do reservatório de Itupararanga com relação à variação nictemeral, sazonal e migração vertical dos organismos na coluna de água e verificar a existência de padrões de variação. Para isto foram realizadas duas coletas no reservatório no ano de 2011: em fevereiro, período chuvoso e em julho, período seco. As coletas foram realizadas no ciclo nictemeral (de 4 em 4 horas), em três diferentes estratos da coluna de água (superfície, meio e fundo) e em dois pontos do reservatório (barragem e corpo central). Foi observada estratificação na coluna de água para ambos os pontos e em ambos os meses. Foram identificadas 25 espécies do mesozooplâncton. Larvas de Chaoborus spp. foram mais abundantes em fevereiro com relação a julho sendo o contrário observado para Cladocera e Copepoda. Entre os Copepoda observou-se dominância dos estágios juvenis (náuplios e copepoditos) para ambos os pontos e em ambos os períodos. Entre os adultos a espécie de Copepoda mais abundante foi Notodiaptomus deitersi (1.298 org.m3) e entre os Cladocera a espécie mais abundante foi Bosmina freyi (32.282 org.m3). O pico de densidade total da comunidade zooplanctônica ocorreu durante o período seco no ponto da barragem com 81.211 org.m3. Chaoborus exerceu pressão de predação sobre os microcrustáceos durante o período chuvoso. Durante o seco, na ausência de Chaoborus na coluna de água, foi observado maior sucesso ecológico para Cladocera e Copepoda. Para todos os grupos foi observado o padrão comum de migração vertical; migração reversa não foi observada. Apesar da pressão de predação, os microcrustáceos não ajustaram sua distribuição vertical de forma a diminuir a sobreposição espacial com Chaoborus. Para todos os grupos considerados o padrão de migração adotado parece ter sido resultado da fuga de predadores e busca por boas condições alimentares.

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Powell, Jesse Russell. "Ocean fronts in the Southern California Current System and their role in structuring zooplankton distributions, diel vertical migration, and size composition." Thesis, University of California, San Diego, 2013. http://pqdtopen.proquest.com/#viewpdf?dispub=3566029.

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Ocean fronts are dynamic gradients that divide waters with differing hydrographic properties. Fronts also play important ecological roles in structuring plankton distributions, modulating primary and secondary production, and delineating predator foraging areas. Here, I utilize autonomous “ Spray” ocean gliders to describe the spatial and seasonal distribution of deep-water fronts and their impact on the plankton within the Southern California Current System (SCCS).

To test the suitability of the Spray’s 750 kHz acoustic doppler profilers (ADP) for mapping zooplankton distributions, I first present results from a seatruthing study in which I mounted an ADP on a Mocness plankton net. I show that the relative mean volume backscatter (rMVBS) measured by the ADP is correlated with the summed zooplankton cross-sectional area (a proxy for biomass). I also find that the relationship between rMVBS and zooplankton biomass is strongest for zooplankters with an estimated spherical diameter greater than 1.6 mm. Observed rMVBS was best explained by euphausiid and copepod biomass.

From Spray cross-shore sections between October, 2006 and December, 2011, I identified 154 distinct surface layer density fronts. The strongest and most numerous fronts occurred in spring, and were located closer to the coast, whereas summer and fall fronts were found further offshore. Fronts were weakest and least numerous in winter. Across all seasons, fronts structured plankton distributions. Horizontal gradients in physical variables (e.g., surface density, temperature, and salinity) co-varied with horizontal gradients in MVBS and Chl-a fluorescence, and the magnitude of biological gradients was higher at frontal areas compared with non-frontal areas. Frontal areas were also clearly associated with elevated Chl -a and zooplankton acoustic backscatter.

Fronts divided distinct plankton habitats and associated assemblages. Chlorophyll-a fluorescence maxima and euphotic zones were deeper offshore of fronts. The amplitude of diel vertical migration by zooplankton also increased offshore, in association with increased optical transparency in the upper ocean. Additionally, ADP data indicate that zooplankton assemblages change across fronts. I employ an inverse acoustic model to estimate zooplankton size spectra, inferring that larger-bodied zooplankters contributed a greater proportion to overall biomass inshore of these fronts. Vertically-stratified zooplankton samples from both inshore and offshore regions corroborated the model results.

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Werner, Thorsten [Verfasser], and Friedrich [Akademischer Betreuer] Buchholz. "Trophic positioning, diel vertical migration and physiological constraints in euphausiid species of the Namibian upwelling system / Thorsten Werner. Betreuer: Friedrich Buchholz." Hamburg : Staats- und Universitätsbibliothek Hamburg, 2013. http://d-nb.info/1041716745/34.

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Ahlbeck, Ida. "Living in a predation matrix : Studies on fish and their prey in a Baltic Sea coastal area." Doctoral thesis, Stockholms universitet, Systemekologiska institutionen, 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-75238.

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This thesis was written within the framework of a biomanipulation project where young-of-the-year (YOY) pikeperch (Sander lucioperca) were stocked to a Baltic Sea bay to improve water quality through a top-down trophic cascade. The aim of my doctorial studies was however focused on a broader ecological question, namely predation (the main driving force in a biomanipulation). Hence, this thesis consists of four papers where we study the interactions between predator and prey using fish and zooplankton and how these interactions can be measured. In paper I we evaluated the performance of different diet analysis methods by individual based modelling and found that when having a nutritional gain perspective, mass based methods described diets best. Paper II investigated how the explorative, foraging and anti-predator behaviour of the YOY pikeperch used for stocking were affected by their rearing environment (pond vs. tank rearing). The more complex and varied environment in the semi-natural ponds seemed to promote a more flexible and active behaviour, better equipping young fish for survival in the wild. For paper III we studied the diel vertical migration in the six copepodite stages of the zooplankton Acartia spp. and Eurytemora affinis in relation to fish biomass, phytoplankton abundance and temperature. Both species migrated and in addition showed increased migration range with size within species, indicating evasion from visual predators. Paper IV addressed the movement of littoral Eurasian perch (Perca fluviatilis) via stable isotope signatures (13C and 15N) and body condition. We found clear indications of sedentarity and intra-habitat dietary differences. Interactions between predators and prey are complex and affected by both physiological and environmental characteristics as well as behavioural traits. The results in this thesis suggest that different species and even different life stages pursue different strategies to survive.
At the time of doctoral defense, the following papers were unpublished and had a status as follows: Paper 1: Submitted. Paper 2: In press. Paper 4: Submitted.

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Baldasso, Luis Fabiano. "Deslocamento Seletivo Induzido do Zooplâncton Marinho em Resposta a Percepção Espectral da Luz Visível." Universidade de São Paulo, 2016. http://www.teses.usp.br/teses/disponiveis/21/21134/tde-16082016-162254/.

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A distribuição da biomassa do plâncton é a chave para o entendimento de vários processos inclusive a compreensão da migração vertical diurna. Entender a fototaxia positiva, como responsável por esta distribuição, com enfoque na qualidade espectral da luz é uma campo vasto a ser explorado. Investigamos a percepção espectral luminosa do mesozooplâncton marinho através da quantificação de capturas em uma nova arte de coleta com armadilha de luz. Estas armadilhas foram testadas com tratamentos luminosos na cor vermelha, verde, azul e branco. Elas foram fundeadas na enseada do Flamengo e de Ubatuba (Ubatuba-SP) no fim do verão e outono de 2015 durante a lua cheia e lua nova em três noites consecutivas. Foram avaliadas as associações de exposição (fase lunar, local de coleta e esquema de randomização dos tratamentos) baseada nos dados de captura através de gráficos NMDS, teste PERMANOVA e tabelas de contingência de Chi-quadrado. Os táxons mais abundantes nas capturas foram dois gêneros de copépodes Calanoida (Acartia sp e Temora sp) seguidos pela família Podonidae e Brachyura. Demonstramos que os organismos capturados do zooplâncton marinho expressaram seleção espectral induzidos pela fototaxia positiva. O tratamento luminoso verde exerceu maior atração nos organismos em detrimento ao tratamento luminoso vermelho. A influência das fases lunares ou dos esquemas de randomização dos tratamentos luminosos dependem da sensibilidade espectral de cada táxon. Porém local não implicou em diferenças entre as coletas. Estas particularidades da fototaxia positiva seletiva podem explicar a variação vertical da biomassa do zooplâncton marinho na coluna d\'água inclusive no entendimento da MVD.
The distribution of plankton biomass is the key for understanding many processes including diel vertical migration (DVM). Understand the positive phototaxis, as responsible for this distribution, with a focus on spectral quality of light is a vast field to be explored. We investigate the spectral light perception of the marine mesozooplankton through quantification of catches in a new art with light trap. These traps were tested with light treatments in red, green, blue and white. They were anchored in the Flamengo and Ubatuba bay (Ubatuba-SP) in late summer and autumn of 2015 during the full moon and new moon on three consecutive nights. Exposure associations were evaluated (lunar phase, site and treatment randomization scheme) based on the data capture through NMDS graphics, PERMANOVA test and Chi-square contingency tables. Most abundant taxa catched were two kinds of copepods Calanoida (Acartia sp and Temora sp) followed by Podonidae and Brachyura. We have demonstrated that the captured marine zooplankton showed spectral selection induced by positive phototaxis. The green light treatment exerted biggest attraction in organisms over the red light treatment. The influence of lunar phases or randomization schemes of bright treatments depend on the spectral sensitivity of each taxon. But location did not result in differences between collections. These specifics of selective phototaxis may explain the vertical variation of marine zooplankton biomass in water column including the understanding of DVM.

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Holliland, Per B. "Trophic interactions and behaviour : Studies relevant to a Baltic Sea biomanipulation." Doctoral thesis, Stockholms universitet, Systemekologiska institutionen, 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-79075.

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The main theme of this thesis is the interactions of animals with the environment and each other. The thesis was written within the framework of a biomanipulation project “Pikeperch in Himmerfjärden”. With the aim to investigate possible trophic pit-falls, give the manipulation the best possible start, and find ways to monitor the progression of the manipulation. In Paper I the diet of the invader cladoceran Cercopagis pengoi is analysed with stable isotopes; conducted prior to stocking. C.pengoi has a preference for large copepods, indicating possible competition with fish. Paper II investigates the behavioural differences between pikeperch fingerlings reared in different environments (pond vs. tank). Results suggest that fish reared in semi-natural ponds are more likely to survive directly after stocking. In Paper III and IV, the diel vertical migrations (DVM) of copepods are in focus. In Paper III the migrations of two copepod species: Acartia spp. and Eurytemora affinis are studied over season and life stage. The amplitude of migration was found to increase with ontogeny for both species, indicating evasion of visual predators. Paper IV examines the varying migratory patterns of adult female E. affinis finding that these animals migrate more actively when feeding conditions deteriorate and growth decreases. The overall conclusions of the thesis are that behavioural, not only direct trophic interactions are key when studying ecosystems.

At the time of the doctoraldefense, the following papers were unpublished and had a status asfollows: Paper2: In press. Paper 4: Manuscript.

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Yazgan, Tavsanoglu Ulku Nihan. "Zooplankton Adaptation Strategies Against Fish Predation In Turkish Shallow Lakes." Phd thesis, METU, 2013. http://etd.lib.metu.edu.tr/upload/12615354/index.pdf.

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In this study, the factors influencing zooplankton community structure in Turkish shallow lakes were elucidated with four main approaches: (i) space-for-time substitution for shallow lakes using snap-shot sampling in 31 lakes along a latitudinal gradient
(ii) in-situ mesocosm experiments in eleven lakes along a latitudinal gradient using three sets of artificial plants systems
(iii)&lsquo
Habitat Choice&rsquo
laboratory experiments mimicking a &lsquo
shallow littoral&rsquo
zone with plants and a &lsquo
deeper pelagic&rsquo
zone with sediments testing the response of Daphnia magna to predation cues
and (iv) long-term monitoring data (1997-2011) from two interconnected lakes. Snap-shot and long-term monitoring showed that eutrophication has a strong influence on the zooplankton community via increased fish predation, nutrient loading and salinization. Here too the zooplankton community shifted towards a smaller sized profile, especially in lakes located at lower latitudes. Moreover, The laboratory and in-situ mesocosm experiments revealed that under predation risk Daphnia preferred to hide near sediment instead of using submerged plants as a refuge. Accordingly, in-situ mesocosm experiments revealed a predation pressure induced size structure shift towards small-medium sized zooplankton and calanoid copepods. The long-term monitored lakes experienced (i) drought-induced water level drop, leading to increased salinity and eutrophication, and consequent anoxic conditions and fish kill
as well as (ii) biomanipulation in the downstream. Both conditions resulted in major reduction in the top-down control of fish and ultimate predomination by large sized Daphnia spp. Nevertheless, the excessive exploitation of lakes and ongoing warming entail Turkish shallow lakes to become more eutrophic, making this study indicative for the Mediterranean region.

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Dean, Cayla Whitney. "Turbulent and Electromagnetic Signature of Small- and Fine-scale Biological and Oceanographic Processes." Diss., NSUWorks, 2018. https://nsuworks.nova.edu/occ_stuetd/492.

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Small- and fine-scale biological and oceanographic processes may have a measurable electromagnetic signature. These types of processes inherently involve turbulence and three-dimensional dynamics. Traditional models of the electromagnetic signature of oceanographic processes are of an analytical nature, do not account for three-dimensional boundary layer dynamics or turbulence, self-inductance, and may not describe the variety of the environmental conditions occurring in the ocean. In order to address this problem, I have implemented magnetohydrodynamic (MHD) computational fluid dynamics (CFD) tools, which has allowed for the evaluation of the electromagnetic signature of a number of small- and fine-scale biological and oceanographic processes in the ocean. The suite of computational tools has included the commercial models ANSYS Fluent, coupled with the MHD module, and ANSYS Maxwell. These computational tools have been well-established in fluid and electromagnetic engineering. The application of CFD and MHD tools in oceanography is new but is undergoing rapid development. In this work, substantial effort was made toward the CFD, MHD, and magnetostatic model verification and identification of model limitations. Verifications of the CFD, MHD, and magnetostatic models were conducted by successfully comparing their results with the field measurements and laboratory experiments. Comparison with the traditional (analytical) models for surface and internal waves, has revealed their limitations related to bottom boundary layer physics, effect of self-inductance, and, to a lesser extent, the magnetic permeability difference at the air-sea interface. These limitations become important for shallow water internal waves. As a result, the traditional models significantly overestimate the magnetic signature of internal waves observed at the Electromagnetic Observatory. After model verification with the field and laboratory data, the computational models were then applied to evaluate the magnetic signature of diel vertical migration (DVM) of zooplankton, surface waves, internal wave solitons, freshwater lens spreading, and Langmuir circulation. The quantitative estimates have been made for typical environmental conditions. In other environmental conditions, their magnetic signature may be somewhat different. The suite of computational models developed in this dissertation work allows for the estimation of the magnetic signature of fine- and small-scale oceanographic processes in virtually any environmental conditions (e.g., in oil emulsions). I anticipate the result of this study will have Naval, environmental, and oil exploration applications.

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Ogonowski, Martin. "Studies on Baltic Sea mysids." Doctoral thesis, Stockholms universitet, Systemekologiska institutionen, 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-75236.

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Mysid shrimps (Mysidacea, Crustacea) are efficient zooplanktivores in both marine and freshwater systems as well as lipid rich prey for many species of fish. Although some efforts have been made to study the role of mysids in the Baltic Sea, very few studies have been carried out in recent time and there are still knowledge gaps regarding various aspects of mysid ecology. This thesis aims to explore some of these gaps by covering a mixture of topics. Using multifrequency hydroacoustics we explored the possibility to separate mysids from fish echoes and successfully established a promising and effective method for obtaining mysid abundance/biomass estimates (paper I). An investigation of the current mysid community in a coastal area of the northern Baltic proper (paper II) demonstrated that the formerly dominant, pelagic mysid Mysis mixta had decreased substantially (~50%) in favor for phytoplanktivorous, juvenile Neomysis integer and Mysis relicta sp. By examining different aspects of mysid behavior, we studied the vertical size distribution of mysids in the field and found that size increased with depth/declining light, irrespective of temperature; indicating that their vertical size distribution primarily is a response to predation (paper II). In paper III, a combination of ecological and genetic markers was used to investigate intraspecific differences in migratory tendency. Both marker types indicated that some part of the Mysis salemaai population is sedentary on the bottom and that this strategy is a phenotypically plastic but persistent trait, analogous to the partial migrations seen in many birds and fishes. In paper IV a temperature and weight specific respiration model was developed for the littoral Praunus flexuosus. Routine respiration was moreover elevated by post-prandial effects (specific dynamic action) for longer times than previously suggested. Consequently, ignoring such effects could significantly bias respiration measurements.
At the time of doctoral defence the following papers were unpublished and had a status as follows: Paper 2: Accepted; Paper 3: Submitted; Paper 4: Accepted

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23

Wingen, Georg. "Vertikale Wanderwellenmodulatoren auf Quantenfilmbasis für die optische Informationsverarbeitung - Vertical travelling-wave modulators using quantum-well material for optical information processing." Gerhard-Mercator-Universitaet Duisburg, 2001. http://www.ub.uni-duisburg.de/ETD-db/theses/available/duett-10122001-113233/.

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The vertical optical travelling-wave modulator represents a new high-frequency element for optical data processing. The modulator is designed for a wavelength of 1200 nm and combines the layered structure of vertical optical modulators based on pseudomorphic InGaAs/GaAs quantum-wells with microwave lines from the MMIC technology. The quantum confined Stark effect is used to modulate the optical signal. The multiple quantum-well structure is embedded into an asymmetrical Fabry-Perot resonator built from a Bragg reflector and an aluminum layer to increase the electrooptical effect. The modulators produces a reflectivity change of 0,28. Large scale travelling-wave modulators are capable of critical frequencies higher than 40 GHz. By varying the width of the central conductor of the microwave line, the slow-wave factor could be varied experimentally between 4.8 and 12,7. The applied microwave produces a modulation lattice along the microwave line which can be used in a high frequency beam-steering element for optical information processing

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24

Gondim, PatrÃcia de Menezes. "Aspectos da ecologia trÃfica e distribuiÃÃo vertical de uma populaÃÃo de Dendropsophus gr. Microcephalus (Anura, Hylidae) em uma area de mata de tabuleiro litorÃneo do Nordeste brasileiro." Universidade Federal do CearÃ, 2012. http://www.teses.ufc.br/tde_busca/arquivo.php?codArquivo=8704.

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Neste trabalho foram realizados estudos sobre a dieta e a estratificaÃÃo vertical em D. gr. microcephalus em uma Ãrea de tabuleiro litorÃneo do nordeste brasileiro. Em relaÃÃo Ã dieta, foram identificados os principais itens alimentares, a ocorrÃncia de variaÃÃo sexual, ontogenÃtica e estacional quanto Ãs presas consumidas, bem como a relaÃÃo do comprimento e volume destas com o comprimento rostro-cloacal e a largura da mandÃbula. Quanto Ã estratificaÃÃo vertical, foram analisadas possÃveis diferenÃas sexuais, ontogenÃticas e estacionais na altura de empoleiramento. Os trabalhos de campo ocorreram mensalmente de marÃo atÃ dezembro de 2011, totalizando dez meses de coletas, obtendo-se uma amostra total de 229 indivÃduos (177 machos, 52 fÃmeas). Foram quantificadas 464 presas distribuÃdas em 15 categorias, sendo Diptera, Coleoptera, Araneae e Hemiptera os principais itens consumidos, composiÃÃo alimentar encontrada na maioria das espÃcies do gÃnero. O predomÃnio de dÃpteros na composiÃÃo alimentar aponta Dendropsophus como um grupo importante de biocontroladores de insetos prejudiciais. FÃmeas apresentaram valores maiores do que machos em relaÃÃo ao comprimento rostro â cloacal (CRC), largura da mandÃbula e massa corpÃrea, sendo largura da mandÃbula a responsÃvel pelas diferenÃas sexuais e ontogenÃticas quando relacionada com comprimento e volume dos itens consumidos. Quanto Ã variaÃÃo estacional, comprimento e volume dos itens alimentares tiveram valores maiores durante a estaÃÃo chuvosa, sugerindo uma abundÃncia maior de presas nesse perÃodo. A altura de empoleiramento em D. gr. microcephalus foi semelhante ao encontrado em outras espÃcies do gÃnero. Adultos se empoleiraram em alturas inferiores, enquanto jovens alcanÃaram alturas maiores, diferenÃas que estÃo relacionadas com a largura da mandÃbula e, possivelmente, com CRC e massa corpÃrea. EstratificaÃÃo vertical devido a variaÃÃes estacionais pode estar ligada a fatores abiÃticos como temperatura, umidade relativa do ar e/ou vento, porÃm, outros estudos devem ser realizados para confirmar a relaÃÃo desses fatores, nÃo sÃ com as variaÃÃes estacionais, mas tambÃm com as variaÃÃes sexuais e ontogenÃticas.
In this work, it was studied the diet and vertical stratification in D. gr. microcephalus in an area of coastal tableland of northeastern Brazil. Regarding diet, it was identified the main food items, the occurrence of sexual, ontogenetic and seasonal variation in relation to the consumed prey, as well as the ratio of length and volume of these with the snout-vent length and jaw width. As for the vertical stratification, it was analyzed possible sex, ontogenetic and seasonal time differences for perch height. The field work took place monthly from March to December 2011, totalizing ten months of collections, obtaining a sample of 229 individuals (177 males, 52 females). It was quantified 464 prey distributed in 15 categories, being Diptera, Coleoptera, Araneae e Hemiptera the main items consumed,food composition found in most species of the genus. The predominance of Diptera in dietary composition points out Dendropsophus as an important group of biocontrol of harmful insects. Females had higher values than males in relation to snout-vent length (SVL), jaw width (JW) and body mass, being jaw width the responsible for the sexual and ontogenetic differences when related to length and volume of items consumed. With regard to seasonal variation, length and volume of food items were greater during the rainy season, suggesting a greater abundance of prey during this period. The height of perch D. gr. microcephalus was similar to that found in other species of the genus. Adults perched at lower altitudes, while youngsters have reached greater heights, differences that are related to the jaw width and possibly to the SVL and body mass. Vertical stratification due to seasonal variations may be linked to abiotic factors such as temperature, relative humidity and / or wind; however, further studies should be conducted to confirm the relationship of these factors, not only with seasonal variations, but also with sexual and ontogenetic variations.

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25

Rütters, Silke. "Die neue Schirm-Gruppenfreistellungsverordnung (EG) Nr. 2790/1999 der Kommission : zu den Ursachen der weitreichenden Reform der EG-Wettbewerbspolitik gegenüber vertikalen Wettbewerbsbeschränkungen und deren materiellrechtlichen Grenzen /." Frankfurt am Main [u.a.] : Lang, 2002. http://www.gbv.de/dms/spk/sbb/recht/toc/346092744.pdf.

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26

Pfeifer, František. "Výroba opěry objemovým tvářením." Master's thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2009. http://www.nusl.cz/ntk/nusl-228787.

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PFEIFER František: Production of support by solid forming. A Graduation Thesis of Master´s Studies, the 5th Year of Study, the School-year 2008/2009, FSI VUT Brno, Department of Machining, May 2009, Pages No. 94, Pictures No. 37, Tables No. 3, Appendixes No. 13. The Graduation Thesis, elaborated in the framework of engineering studies, presents the production technology of support component from steel ČSN 12 010. A material is a rod of the 130 – 251 ČSN 42 5510. A yearly production is 95 000 pieces. Based on the studies of possible production technologies was proposed the technology of production by the vertical forging press LMZ 6500B (Šmeral Brno a. s.) with a nominal forming power of 65 MN, flash and pellicle trimming on a trimming press with a nominal power of 8 MN. For this option, the required technological calculations, the design of the die, the specification of production machines and a simulation forming process which is made in the software QFORM have been carried out.

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27

Henk-Merten, Katrin. "Die Kosten-Preis-Schere im Kartellrecht /." Köln ; Berlin ; München : Heymann, 2004. http://swbplus.bsz-bw.de/bsz115686134vlg.htm.

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28

Wolfer, Marcel. "Die vertikale Kompetenzordnung im EG-Beihilfeaufsichtsrecht." Hamburg Kovač, 2007. http://d-nb.info/988939169/04.

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Wolfer, Marcel. "Die vertikale Kompetenzordnung im EG-Beihilfeaufsichtsrecht /." Hamburg : Kovač, 2008. http://www.verlagdrkovac.de/978-3-8300-3817-7.htm.

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30

Tolsdorff, Boris. "Einfluss von Augenmotilitätsstörungen auf die subjektive Vertikale." [S.l.] : [s.n.], 2002. http://deposit.ddb.de/cgi-bin/dokserv?idn=969348975.

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31

Dengler, Marcus. "Über die Tiefenzirkulation und die vertikale Vermischung im nordwestlichen Indischen Ozean." [S.l. : s.n.], 2000. http://www.sub.uni-hamburg.de/disse/311/titel.html.

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32

Geiger, Patric Kurt. "Vertikal gezogene multikristalline Si-Folien für die Photovoltaik Charakterisierung und Solarzellenprozessierung /." [S.l. : s.n.], 2003. http://deposit.ddb.de/cgi-bin/dokserv?idn=968376738.

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33

Brunn, Thomas. "Die EG-Kartellverfahrensverordnung 1/2003 und ihre Auswirkungen auf die Gruppenfreistellungsverordnungen und die Entzugsverfahren der Vertikal-GVO /." Frankfurt am Main [u.a.] : Lang, 2004. http://www.gbv.de/dms/spk/sbb/recht/toc/387845151.pdf.

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34

Špaček, Antonín. "Výroba držáku objemovým tvářením." Master's thesis, Vysoké učení technické v Brně. Fakulta strojního inženýrství, 2008. http://www.nusl.cz/ntk/nusl-228130.

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The diploma thesis deals with suggestion of low alloy 14220.0, produced by solid forming. This suggestion is based on the size of series that contain 100 000 pieces a year. The essay contains knowledge refering to drop forging technology and comparison with existing technologies. Two suitable variants of production were assessed, these variants are drop forging with hammers and vertical forging press. Both theories were theoretically analised in order to describe given technology. The analysis also contains calculation and suitable machine choice. Drop filling on vertical forging presses was chosen because of forging type. Furthemore forging proposition was treated including production technique. The chosen variant contains calculation, suggestion of a die, machine that was used and suggestion of flash trimming. For suggested technology was chosen vertical press LZK 3150 B. Its producer is Šmeral a.s. Brno. This project also contains technical drawings of the given component, forge, dies and phase of forging.

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35

Teichmann, Emanuel [Verfasser]. "Die Reformbedürftigkeit der Vertikal-GVO am Beispiel von Plattformverboten und Preisparitätsklauseln / Emanuel Teichmann." Baden-Baden : Nomos Verlagsgesellschaft mbH & Co. KG, 2020. http://d-nb.info/1220162469/34.

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36

Kirchhain, Simone. "Die Anwendung der Vertikal-GVO auf innerstaatliche Wettbewerbsbeschränkungen nach der 7. GWB-Novelle." Frankfurt,M. Berlin Bern Bruxelles New York, NY Oxford Wien Lang, 2006. http://d-nb.info/98596135X/04.

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37

Erdmann, Markus. "Vertikale Vereinbarungen im Kfz-Sektor die neue GVO 1400/2002." Hamburg Kovač, 2006. http://www.verlagdrkovac.de/3-8300-2553-X.htm.

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38

Nelißen, Bernd. "Die Abgrenzung "horizontaler" und "vertikaler" Wettbewerbsbeschränkungen nach der 6. GWB-Novelle /." Frankfurt am Main [u.a.] : Lang, 2001. http://www.gbv.de/dms/spk/sbb/recht/toc/329565508.pdf.

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39

Roitman, David. "Reform des EG-Wettbewerbsrechts : Die Gruppenfreistellungsverordnung für vertikale Vertriebsvereinbarungen und damit verbundene Aspekte der Verordnung 1/ 2003 /." Hamburg : Kovač, 2006. http://www.verlagdrkovac.de/3-8300-2204-2.htm.

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40

Meyer, zu Knolle Sigrid. "Die gebändigte Vertikale Materialien zum frühen Hochhausbau in Frankfurt am Main /." [S.l.] : [s.n.], 1999. http://archiv.ub.uni-marburg.de/diss/z2002/0458.

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41

Morita, Fernanda Soares da Silva. "Efeitos da derivação gástrica em Y de Roux e da gastrectomia vertical sobre o metabolismo lipídico hepático em ratos obesos." Universidade Estadual do Oeste do Paraná, 2017. http://tede.unioeste.br/handle/tede/3436.

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Submitted by Edineia Teixeira (edineia.teixeira@unioeste.br) on 2018-02-27T12:47:21Z No. of bitstreams: 2 Fernanda_Morita2017.pdf: 1916527 bytes, checksum: d53cab0d448357d03f1447766ef5948a (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5)
Made available in DSpace on 2018-02-27T12:47:21Z (GMT). No. of bitstreams: 2 Fernanda_Morita2017.pdf: 1916527 bytes, checksum: d53cab0d448357d03f1447766ef5948a (MD5) license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) Previous issue date: 2017-08-25
Conselho Nacional de Pesquisa e Desenvolvimento Científico e Tecnológico - CNPq
Objective: Here, we compared the effects of Roux-en-Y gastric bypass (RYGB) and sleeve gastrectomy (SG) on fat liver deposition and expression of hepatic enzymes involved in hepatic de novo (DN) lipogenesis and β-oxidation, in western diet (WD)-obese rats. Background: Bariatric operations are known to improve non-alcoholic fatty liver disease (NAFLD), often found in obese humans. However, comparative studies on the efficacy of different bariatric procedures against NAFLD are scarce. Methods: At two months after WD consumption, the rats were divided into three groups: WD sham operation (WD-Sham), WD-RYGB and WD-SG. Three months after procedures, hepatic steatosis and lipid metabolism were verified. Results: After 3 months, body weight and abdominal fat mass were lower in WD-RYGB, compared with WD-SG rats. Both bariatric operations enhanced glucose tolerance and decreased triglycerides (TG) serum levels. However, total serum cholesterol (CHOL) as well as, hepatic TG and CHOL contents were reduced only in liver of WD-RYGB rats. Hepatic steatosis was corrected in 83% of the WD-RYGB rats, whereas microvesicular steatosis occurred in 100% of the WD-SG livers. Reduction in FASN protein content was observed in both WD-RYGB and WD-SG rats. However, reduced hepatic ACC and enhanced pACC/ACC and CPT-1a protein levels were observed only in WD-RYGB rats. Conclusions: NAFLD is more marked reduced in obese rats that underwent RYGB than SG procedures. This RYGB effect may be associated with decreased hepatic DN lipogenesis, associated with enhancement in β-oxidation, which reduced TG and CHOL content in the liver and serum of WD rats.
Introdução: As operações bariátricas são conhecidas por melhorar a doença hepática gordurosa não alcoólica (DHGNA), frequentemente encontrada em indivíduos obesos. No entanto, estudos que comparam a eficácia de diferentes procedimentos bariátricos sobre a DHGNA são escassos. Objetivo: Nesse trabalho, são comparados os efeitos da Derivação Gástrica em Y de Roux (DGYR) e da Gastrectomia Vertical (GV) sobre a esteatose hepática e sobre a expressão de enzimas envolvidas na lipogênese de novo e β-oxidação no fígado de ratos obesos pela dieta de cafeteria. Métodos: Dois meses após o consumo de dieta de cafeteria, os ratos foram divididos aleatoriamente em três grupos: cafeteria pseudo-cirúrgico (CAF-PC), cafeteria derivação gástrica em Y Roux (CAF-DGYR) e cafeteria gastrectomia vertical (CAF-GV). Três meses após os procedimentos cirúrgicos, a esteatose hepática e o metabolismo lipídico foram avaliados. Resultados: Três meses após os procedimentos operatórios, os animais CAF-DGYR apresentaram menor peso corporal e gordura abdominal em comparação com os ratos CAF-PC e CAF-GV. Ambas as operações bariátricas aumentaram a tolerância à glicose e diminuíram a concentração de triglicerídeos (TG) plasmáticos. No entanto, o colesterol total (COL), bem como as concentrações de TG e COL hepáticos, foram reduzidos apenas no fígado dos ratos CAF-DGYR. A esteatose hepática foi corrigida em 83% dos ratos CAF-DGYR, enquanto que os animais CAF-GV apresentaram 100% de esteatose microvesicular. Os ratos CAF-DGYR e CAF-GV apresentaram redução na expressão proteica da FASN. No entanto, apenas os animais CAF-DGYR tiveram redução da proteína ACC e aumento da razão da pACC/ACC e CPT-1a. Conclusões: A operação de DGYR foi mais eficaz na redução da DHGNA em ratos obesos, em comparação com a GV. Esse efeito da DGYR pode estar associado à diminuição da lipogênese hepática de novo, associado ao aumento da β-oxidação, que levou à redução das concentrações de TG e COL no plasma e no fígado de ratos obesos por dieta de cafeteria.

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Eisold, Hans-Elmar. "Von Horizontal zu Vertikal: Ein kurzer Abriss über die (technische) Entwicklung der äußeren Form klassischer Windmühlen." Hans-Elmar Eisold, 2012. https://slub.qucosa.de/id/qucosa%3A7296.

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Die Bedeutung der (Wind)Mühle als kultur- und technikgeschichtlicher Meilenstein ist durch die mit ihr einhergehende Erhöhung der Leistungsfähigkeit des Kornmahlens unbestritten. Interessant ist die technisches Entwicklung der Windmühle sowohl aus ihren geographischen wie kulturellen, d. h. religiösen, Wurzeln. Auf den folgenden Seiten werden im wesentlichen grundlegende technisches Entwicklungsbedingungen und Typen der klassischen Windmühle überblicksartig zusammengefasst sowie eine Entwicklungsabfolge dargelegt. Ausgangspunkt ist dabei mit der Horizontalwindmühle der erste bekannte Windmühlentyp. Die Holländerwindmühle soll als Gipfel traditioneller Windmühlen den Endpunkt dieser Betrachtung bilden.:1 Historisches 1.1 Vom Reibstein zum Drehstein zur Mühle . . . . . 1 1.2 Bedeutung der Klöster . . . . . 2 1.3 Nutzung der Windkraft als Mühlenantrieb . . . . . 3 2 Technisches 2.1 Horizontalwindmühle . . . . . 3 2.2 Vertikalwindmühle . . . . .5 2.2.1 Segelwindmühle oder Mittelmehrtyp . . . . .5 2.2.2 Bockwindmühle . . . . .6 2.2.3 Rollbockwindmühle . . . . .8 2.2.4 Paltrockwindmühle . . . . .9 2.2.5 Kokerwindmühle . . . . .10 2.2.6 Holländerwindmühle . . . . .11 3 Zusammenfassung 12 Literatur 15

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43

Wingen, Georg [Verfasser], and Dieter [Akademischer Betreuer] Jäger. "Vertikale Wanderwellenmodulatoren auf Quantenfilmbasis für die optische Informationsverarbeitung / Georg Wingen ; Betreuer: Dieter Jäger." Duisburg, 2006. http://d-nb.info/1193732832/34.

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44

Wiontzek, Felix. "Vergleichende In-vitro-Untersuchungen über die vertikale Belastbarkeit konfektionierter Präzisionsgeschiebe in der zahnärztlichen Prothetik." [S.l.] : [s.n.], 2004. http://deposit.ddb.de/cgi-bin/dokserv?idn=974207810.

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45

Vladimirova, Kremena. "Nouveaux concepts pour l'intégration 3D et le refroidissement des semi-conducteurs de puissance à structure verticale." Phd thesis, Université de Grenoble, 2012. http://tel.archives-ouvertes.fr/tel-00738000.

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L'électronique de puissance est en pleine mutation matérielle, technologique et conceptuelle. Cette évolution bouscule l'approche traditionnelle de la conception et de la fabrication des convertisseurs statiques avec pour objectif de proposer des solutions plus performantes, plus fiables et plus compactes et tout cela dans un contexte technico économique de plus en plus exigeant. Cette thèse analyse et expérimente un concept innovant de terminaisons en tension verticales ouvrant la voie vers l'intégration en 3D des composants de puissance mais également l'intégration, au sein même de la zone active d'un échangeur thermique. En s'appuyant sur la technique de réalisation des tranchées profondes issue de la micro électronique, ce document présente une approche permettant la co-intégration de plusieurs composants de puissance indépendants partageant la même électrode et le même substrat en face arrière. L'autre volet de ce travail de thèse est focalisé sur le concept DRIM Cooler (Drift Region Integrated Microchannel Cooler), un réseau de microcanaux perpendiculaires au plan de jonction du composant de puissance permettant son refroidissement direct. Les analyses numériques sont complétées par de nombreuses réalisations, caractérisations et mises en œuvre des approches précitées.

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46

Schmid, Ekaterina. "Einfluss der Züchtungsbedingungen auf die Eigenschaften von mc-Si-Kristallen." Doctoral thesis, Technische Universitaet Bergakademie Freiberg Universitaetsbibliothek "Georgius Agricola", 2016. http://nbn-resolving.de/urn:nbn:de:bsz:105-qucosa-199263.

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Die vorliegende Arbeit befasst sich mit den Untersuchungen zum Einfluss der Züchtungsbedingungen auf die Eigenschaften von multikristallinen (mc) Silizium-Kristallen. Im Mittelpunkt stehen Züchtungsexperimente mit einer gezielten Variation der Züchtungsaufbauten und Züchtungsgeschwindigkeiten. Die gezüchteten Kristalle wurden umfassend charakterisiert im Hinblick auf die Kohlenstoffkonzentration, die Kornstruktur, die Vesetzungsdichte, Verteilung der Ausscheidungen und Ladungsträgerlebensdauer. Zusätzlich wurde die Versetzungsanordnung in Abhängigkeit von der Wachstumsrate bzw. Abkühlrate systematisch untersucht. Als Ergebnis wurde gezeigt, dass die Züchtungsbedingungen die Kohlenstoffkonzentration, die Versetzungsdichte, die Bildung von den Ausscheidungen sowie die Ladungsträgerlebensdauer beeinflussen können, jedoch nicht die Korngröße. Es wurde ein direkter Zusammenhang zwischen Ausscheidungsgebieten und erhöhte Versetzungsdichte beobachtet. Im Rahmen der Arbeit wurde festgestellt, dass die endgültige Versetzungsstruktur sich als Resultat von Gleit- und Erholungsprozessen darstellt.

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47

Kaufmann, Christian. "Wettbewerbsrechtliche Behandlung vertikaler Abreden : die allgemeine Bekanntmachung der Wettbewerbskommission unter Berücksichtigung der Bekanntmachung über den Automobilvertrieb und der Revision des Kartellgesetzes /." Zürich [u.a.] : Schulthess, 2004. http://www.gbv.de/dms/spk/sbb/recht/toc/379623714.pdf.

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48

Rangel, Cristiane Hollanda. "Ecologia e comportamento de Callitrichidae (Primates) no Jardim Botânico do Rio de Janeiro." Universidade do Estado do Rio de Janeiro, 2012. http://www.bdtd.uerj.br/tde_busca/arquivo.php?codArquivo=4192.

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Espécies exóticas são consideradas a segunda maior ameaça ao meio ambiente, sendo um risco às espécies nativas devido à predação, competição, hibridação e transmissão de patógenos. Callithrix jacchus e Callithrix penicillata são espécies exóticas amplamente difundidas no Estado do Rio de Janeiro. No presente estudo, dados comportamentais e ecológicos foram amostrados entre Setembro de 2008 e Agosto de 2009 usando-se o método animal focal com amostragem instantânea, acompanhando sete grupos mistos de Callithrix spp. no arboreto do Jardim Botânico do Rio de Janeiro (JBRJ). A densidade dos saguis foi estimada em cerca de 130 indivíduos por Km2. Na dieta, foram identificadas 51 espécies arbóreas fontes de exsudatos e 39 espécies fontes de frutos, folhas, flores e néctar. Os saguis se alimentaram também de invertebrados, pequenos vertebrados, e alimentos direta ou indiretamente fornecidos por visitantes do JBRJ. O consumo de exsudatos foi maior na estação mais seca, e de frutos e insetos na estação mais chuvosa. Os saguis utilizaram mais os estratos verticais intermediários e sub-bosque nas suas atividades diárias, e áreas protegidas por epífitas no dossel de 30 espécies diferentes de árvores como locais de dormida. Os saguis apresentaram relações interespecíficas harmônicas, neutras e desarmônicas com diversas espécies de aves e mamíferos. A dispersão de sementes de árvores exóticas e o uso exagerado de espécimes vegetais para gomivoria pelos saguis podem afetar a integridade da coleção do JBRJ. A alta densidade de saguis e predação de espécies da fauna local podem afetar o equilíbrio da comunidade faunística. Com base nas observações in situ, as espécies alóctones C. jacchus e C. penicillata causam danos e necessitam de manejo, que deve ser estudado e implementado para o controle criterioso de suas populações.
Exotic species are considered the second biggest threat to the environment, representing a risk to native species due to predation, competition, hybridization and disease transmission. Callithrix jacchus and C. penicillata are exotic species widely spread out in the Rio de Janeiro State. For this study, behavioural and ecological data were sampled between September 2008 and August 2009 through the use of focal animal method with instantaneous sampling, following seven mixed groups of Callithrix spp. in the Arboretum of Rio de Janeiro Botanic Garden (JBRJ), Rio de Janeiro. The marmoset density was estimated on 130 individuals per km2. We identified 51 tree species as exudate sources, 39 species as sources of fruits, leaves, flowers and nectar. The marmosets can also eat invertebrates, small vertebrates, and food offered by visitors of JBRJ. The consumption of exudates was concentrated in the dry season, and fruit and insects in the rainy season. The marmosets used most intermediate strata and understory in their daily activities, and areas protected by epiphytes in the canopy of 30 different species of trees as sleeping sites. The marmosets showed interspecific relationships as harmonic, neutral and disharmonious with several species of birds and mammals. The diffusion of exotic tree seeds and the overuse of plant specimens for gummivory of marmosets can affect the integrity of the JBRJ collection. The high density of marmosets and predation of native fauna can affect the integrity of the fauna. Considering the potential and observed damage caused by exotic species Callithrix jacchus and C. penicillata, management measures should be studied and implemented to control their populations.

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Burger, Simon [Verfasser]. "Verantwortung und Verantwortlichkeit für die Umsetzung supranationalen Rechts im Bundesstaat : Die horizontale und vertikale Zuordnung der Umsetzungspflichten einschließlich der Haftung / Simon Burger." Aachen : Shaker, 2010. http://d-nb.info/1084536579/34.

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Hessler, Markus A. "Die Vorwärtsintegration der großen Energieversorgungsunternehmen auf dem deutschen Markt : eine wettbewerbsökonomische Analyse ; Grundlagen, aktueller Stand, Wettbewerbspolitik, Wettbewerbsökonomik, Lösungsansätze, Ausblick /." Norderstedt : Books on Demand, 2008. http://www.gbv.de/dms/zbw/568940679.pdf.

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Dissertations / Theses on the topic 'Diel vertical'

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