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Bos, Merijn M. "Insect diversity and trophic interactions in shaded cacao agroforestry and natural forests in Indonesia." Doctoral thesis, [S.l.] : [s.n.], 2006. http://webdoc.sub.gwdg.de/diss/2006/bos.
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Rocha, Carolina Camargo. "Avaliações ultrassonográficas, morfométricas e histológicas testiculares de touros Bos taurus taurus submetidos a insulação escrotal sob o tratamento sistêmico com antioxidante e suplementado com ácidos graxos poli-insaturados." Universidade de São Paulo, 2013. http://www.teses.usp.br/teses/disponiveis/10/10131/tde-01072013-112224/.
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Vários estudos indicam uma maior susceptibilidade ao estresse térmico de touros europeus quando criados em regiões tropicais, levando a efeitos deletérios à reprodução (e.g., diminuição da qualidade espermática, degeneração testicular). Tal fato pode causar expressivo prejuízo econômico visto que, nestas regiões, a estação de monta é realizada no verão. Um dos principais mecanismos propostos para explicar este efeito seria um aumento do estresse oxidativo. Assim, uma alternativa promissora seria o tratamento com antioxidantes e ácidos graxos poli-insaturados. O presente estudo tem como objetivo: Avaliar os possíveis efeitos benéficos da suplementação oral com ácidos graxos poli-insaturados (com vs. sem) e a ação protetora do tratamento sistêmico com vitamina E (com vs. sem) contra os danos oxidativos causados pelo estresse térmico testicular em touros taurinos insulados através das avaliações ultrassonográfica, morfométrica testicular (i.e, volume, temperatura, consistência, circunferência) e histológica dos testículos. Para isso, foram utilizados 16 touros Bos taurus taurus jovens (em torno de 2 anos de idade) divididos em 4 grupos (fatorial 2x2) com perfil espermático normal. Todos os animais foram submetidos à insulação testicular por um período de 96 horas. Foi realizada a ultrassonografia testicular a cada 13 dias por todo o período e mais dois meses após o período da insulação. Como controles foram avaliados os testículos dos touros antes da insulação. Concomitante à insulação, os animais foram divididos aleatoriamente em 4 lotes que foram submetidos a um arranjo fatorial 2x2, sendo um dos fatores a dieta rica em PUFA (Ácidos graxos poli-insaturados Megalac E®) todo o dia durante dois meses pós insulação. Já o tratamento sistêmico com Vitamina E (Monovin E®) foi realizado através da injeção subcutânea de 5 ml de α-tocoferol a cada 13 dias pós insulação com duração de dois meses pós insulação. Aos animais que não receberam a vitamina E, foi administrado o mesmo volume em placebo (óleo inerte). No final deste período, os animais foram castrados e os testículos utilizados para a histologia. Os resultados foram analisados através do SAS system for Windows e indicaram que tanto a suplementação oral de ácidos graxo poli-insaturados como o tratamento sistêmico com vitamina E, não alteraram as características ultrassonográficas, morfométricas e histológicas testiculares de touros de origem europeia submetidos a insulação testicular.Several studies indicate an increased susceptibility to the heat stress in European bulls raised under tropical conditions, which leads to deleterious effects on reproduction (e.g., testicular degeneration, impaired sperm quality). This may cause significant economic losses since, in these regions, breeding season usually occurs during summer. The main mechanism proposed to explain such event is the oxidative stress. Therefore, an alternative to overcome this effect would be the treatment with antioxidant combined with a supplementation with poly-unsaturated fatty acids (PUFA). The present study aimed to evaluate the possible beneficial effect of the oral PUFA supplementation combined with a protective antioxidant treatment to overcome the deleterious effects of the heat stress on testicular echogenicity, morphometry (i.e., volume, circumference, consistency) and histology. Towards this aim, 16 young but sexually mature Bos taurus taurus (around 2 years old). All animals were submitted to testicular warming for 96 hours. Simultaneously to the insulation, animals were randomly allocated into 4 groups in a 2x2 fatorial design. One of the factors was a PUFA supplementation (supplemented vs. nonsupplemented; Megalac E®) everyday for two months. The other factor was a systemic treatment with a subcutaneous administration of 5 mL of α-tocopherol (treated vs. non treated) every 13 days for two months. Animal that did not receive the treatment were injected with 5 mL of inert oil. Testicular ultrasound evaluation was performed each 13 days from the beginning until two months after testicular warming. At the end of the period experimental period, animals were castrated and the testicles were submitted to histological evaluation. Data were statistically analyzed using the SAS system for Windows. Results indicated that oral PUFA supplementation combined with the systemic -tocopherol treatment had no influence on testicular echogenicity, morphometry and hystology in European bulls submitted to testicular warming.
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Mburu, Francis Gérardin Philippe. "Etude et valorisation de différents bois du Kenya Study and valorization of different Kenyan wood species /." [S.l.] : [s.n.], 2007. http://www.scd.uhp-nancy.fr/docnum/SCD_T_2007_0057_MBURU.pdf.
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VAJANA, ELIA. "Studio della storia evoluzionistica e conservazione delle specie zootecniche attraverso analisi di genomica del paesaggio e modelli di nicchia ecologica." Doctoral thesis, Università Cattolica del Sacro Cuore, 2017. http://hdl.handle.net/10280/19085.
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Attività antropiche e pressioni di mercato stanno rapidamente riducendo la biodiversità. Per questa ragione, conservare il patrimonio ecosistemico, tassonomico e genetico risulta fondamentale al fine di garantire potenziale adattativo alle specie, e, in ultima analisi, un futuro sostenibile per il pianeta. Al fine di minimizzare la perdita di biodiversità, numerosi metodi sono stati proposti per priorizzare ecosistemi, specie e popolazioni. Il presente lavoro di tesi fornisce in primo luogo una revisione di tali approcci, proponendo un albero decisionale volto a favorirne un corretto utilizzo. Secondariamente, la variabilità genomica neutrale del bufalo d’acqua (Bubalus bubalis L.) è investigata per mezzo di un pannello di marcatori SNP a media densità, rivelando due centri di domesticazione (India Nord-occidentale, Cina-Indocina) e possibili rotte di migrazione per gli ecotipi ‘river’ e ‘swamp’. L’adattamento locale ad East Coast Fever, patologia endemica delle popolazioni bovine in Africa Sub-sahariana, è stato inoltre studiato in bovini autoctoni Ugandesi (Bos taurus L.) combinando tecniche di modellizzazione delle nicchie ecologiche e di genomica del paesaggio. L’approccio ha portato ad indentificare PRKG1 e SLA2 come possibili geni di adattamento. I risultati sono discussi alla luce delle possibili implicazioni nella conservazione del bufalo e nella gestione delle risorse genetiche animali Ugandesi.Biodiversity is quickly disappearing due to human impact on the biosphere, and to market pressure. Consequently, the protection of both wild and domestic species needs to become a priority in order to preserve their evolutionary potential and, ultimately, guarantee a sustainable future for coming human generations. To date, tens of methods have been proposed to prioritize biodiversity for conservation purposes. Here, an ontology for priority setting in conservation biology is provided with the aim of supporting the selection of the most opportune methodologies given specific conservation goals. Further, two case studies are presented characterizing neutral and adaptive genomic diversity in water buffalo (Bubalus bubalis L.) and indigenous Ugandan cattle (Bos taurus L.), respectively. In particular, two independent domestication centres (North-western India and Indochina) and separate migration routes are suggested for the ‘river’ and ‘swamp’ water buffalo types. In the case of indigenous Ugandan cattle, the integration of species distribution modelling and landscape genomics techniques allowed the identification of PRKG1 and SLA2 as candidate genes for local adaptation to East Coast Fever, a vector-borne disease affecting bovine populations of Sub-Saharan Africa. Results are discussed for their implications in water buffalo conservation and Ugandan cattle adaptive management.
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Greenup, Alison Laura. "Responses of peatland vegetation and methane flux to environmental change." Thesis, University of Sheffield, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.327727.
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Loizou, T. "Describing bog surfaces." Thesis, University of Dundee, 1994. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.366994.
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Cassata, Joseph Frank. "Relay Protection Scheme for Special Power Flow Controllers." Youngstown State University / OhioLINK, 2020. http://rave.ohiolink.edu/etdc/view?acc_num=ysu1595355623363128.
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Salter, Paul Andrew. "Novel bis(calix[4]arene) based systems for the selective recognition of anionic guest species." Thesis, University of Oxford, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.365400.
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Sewell, Laura Jane. "Exploring the reactivity patterns of cationic and neutral rhodium bis-phosphine species with amine-boranes." Thesis, University of Oxford, 2013. http://ora.ox.ac.uk/objects/uuid:21b883f1-9ffd-4589-ad82-1243b988af91.
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This thesis details the synthesis of novel Rh(I) and Rh(III) bis-phosphine fragments, and their use, along with other known rhodium species, to investigate the reactivity of amine-boranes, with a particular focus on the dehydrocoupling of the secondary amine-borane H3B.NMe2H (DMAB). Chapter 2 utilises the new mixed phosphine, PtBuiBu2, to investigate the role of the phosphine with regard to the corresponding low-coordinate organometallic species isolated. Their coordination and reactivity with amine-boranes is studied, leading to the development of a mechanism for an alkene hydroboration catalyst that employs H3B.NMe3 (TMAB). The final section of the chapter studies several fluxional processes pertinent to rhodium and iridium complexes of the model amine-borane TMAB using H/D exchange and low temperature NMR experiments. In Chapter 3, the mechanism of dehydrocoupling of DMAB is investigated in detail, employing catalysts based on the cationic bis¬-phosphine Rh fragment, {Rh(PCy3)2Ln}+. A series of stoichiometric and catalytic reactions are probed using NMR spectroscopy and mass spectrometry, revealing a complex mechanistic landscape. Subtleties include: the product of dehydrocoupling, [H2BNMe2]2, acting in an autocatalytic role; and parallel dehydrogenation of DMAB by a neutral catalyst present in a low but constant concentration. The mechanism was additionally interrogated through kinetic simulations conducted by Prof. Guy C. Lloyd-Jones (University of Bristol). From this, a generic mechanistic scheme has been suggested, aspects of which can be applied to transition metal and main group systems reported to catalyse the dehydrocoupling of DMAB. The final chapter moves on from cationic rhodium fragments to investigate the reactivity of the neutral rhodium species, Rh(H)2(PCy3)2Cl and [Rh(PCy3)2Cl]2, with amine-boranes. The mechanism by which Rh(H)2(PCy3)2Cl catalyses the dehydrogenation of DMAB has been investigated through initial rate and H/D exchange experiments, leading to the proposal of a reaction scheme. Additionally, the formation and characterisation of a base-stabilised boryl species has been reported resulting from the reactivity of an amino-borane with [Rh(PCy3)2Cl]2.
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Leite, Yuri L. R. "Evolution and systematics of the Atlantic tree rats, genus Phyllomys (Rodentia, Echimyidae), with description of two new species /." Berkeley, Calif. [u.a.] : Univ. of California Press, 2003. http://www.loc.gov/catdir/bios/ucal051/2004297025.html.
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Bartsch, Annette. "Die Eisalgenflora des Weddelmeeres (Antarktis): Artenzusammensetzung und Biomasse sowie Ökophysiologie ausgewählter Arten = Sea ice algae of the Wedddell Sea (Antarctica): species composition, biomass, and ecophysiology of selected species /." Bremerhaven : Alfred-Wegener-Inst. für Polar- und Meeresforschung, 1989. http://www.gbv.de/dms/bs/toc/016186044.pdf.
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Ruuska, J. (Jari). "Special measurements and control models for a basic oxygen furnace (BOF)." Doctoral thesis, Oulun yliopisto, 2012. http://urn.fi/urn:isbn:9789514298028.
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Abstract The target in this thesis was to study selected special measurements in a basic oxygen furnace (BOF) and develop a model to predict the steel temperature at the end of the oxygen blow. Furthermore, the work aimed at increasing knowledge on measurements and phenomena in the converter and in this way improve the possibility of more efficient monitoring and control of the process. Special measurements were investigated to obtain more knowledge about their usability in running the converter process. Analysing the measurement results also led to new process knowledge. The usage of a Radio Wave Interferometer (RWI) was seen as beneficial as it makes it possible to see the rising trend of the liquid surface level in advance and to perform some corrective actions to avoid excessive foaming and possible splashing out from the converter. Acoustic measurement could also detect trends in advance, but it was found to be sensitive to disturbing noise from the surroundings. Splashing measurement gives information about the current state of the slag but not advance information. Nevertheless, the measurements revealed several factors that usually increase splashing. It would be best to use the knowledge from two different measurements, for example RWI and splashing measurement, to predict increasing splashing, which causes significant iron losses. The development of the models for end temperature prediction and additional materials provided a lot of knowledge about the factors affecting the temperature. Factors that were used in grouping were the BOF number, heat size and end carbon content. However, there were many heats that did not satisfy the target. Furthermore, there is a need for additional research into temperature progress and its control in BOF. It would also be useful to study the effect of additional materials more systematically. There are other factors, such as the oxygen flow rate and lance height, which affect the temperature that are not included in the models. Some of the factors are measurable and some are not. There is still a need for more research in this area. This work strengthens the impression that the converter process is a complex one. It was noticed; as always in process development, that continuous monitoring and efforts are required to observe the changes in process conditions, raw materials or running practices. Otherwise, the benefit of the improvements and models will be lessened. However, it would be possible to set acknowledged routines and warnings into the improved monitoring system to help the operators notice the need for system tuning. A monitoring system would provide financial benefits in terms of having fewer reblowings, better yield and better quality of final product. Savings in raw materials can also be attained as the controllability of the process becomes better. As the monitoring system contains a database of guidelines, it would form a good basis for new employees to become familiar with the process and thus facilitate their trainingTiivistelmä Tämän opinnäytteen tarkoitus oli tutkia teräskonvertterin valittuja erikoismittauksia ja kehittää malli ennustamaan teräksen lämpötilaa happipuhalluksen lopussa. Työn tarkoituksena oli lisätä tietämystä mittauksista ja ilmiöistä konvertterissa ja tällä tapaa lisätä mahdollisuuksia prosessin tehokkaampaan monitorointiin ja ohjaukseen. Erikoismittauksia tutkittiin lisätietämyksen saamiseksi niiden käytettävyydestä konvertteriprosessin ajossa. Mittausten analysointi tuotti myös uutta prosessitietämystä. Radioaaltointerferometrin (RWI) käyttö koettiin hyödylliseksi, koska on mahdollista havaita kuonan pinnankorkeuden nousu ennakkoon ja suorittaa joitakin korjaavia toimenpiteitä liiallisen kuohumisen ja lopulta roiskumisen estämiseksi ulos konvertterista. Äänimittaus voi myös havaita trendin ennakkoon, mutta huomattiin sen olevan herkkä ympäristön häiriöäänille. Roiskemittaus antaa tietoa kuonan sen hetkisestä tilasta, mutta ei ennakkoon. Mittaukset toivat kuitenkin esiin useita tekijöitä, jotka yleensä lisäävät roiskumista. Olisi parasta käyttää kahden eri mittauksen tietoa, RWI ja roiskemittaus, ennustettaessa lisääntyvää roiskumista, joka aiheuttaa huomattavia rautahäviöitä. Loppulämpötilan ennustamiseen kehitetyn mallin ja lisäainemallin kehittäminen antoi paljon tietoa tekijöistä, jotka vaikuttavat lämpötilaan. Tekijät, joita käytettiin ryhmittelyssä, olivat konvertterinumero, panoskoko ja loppuhiilipitoisuus. Mallin soveltamisesta huolimatta jäi edelleen useita sulatuksia, jotka eivät osuneet tavoitteeseen. On edelleen tarve teräskonvertterin lämpötilakäyttäytymisen ja sen hallinnan lisätutkimukselle konvertterissa. Myös lisäaineiden vaikutusta lämpötilaan olisi hyödyllistä tutkia systemaattisemmin. On edelleen muita tekijöitä, esimerkiksi hapen virtausnopeus ja lanssin korkeus, jotka vaikuttavat lämpötilaan, mutta jotka eivät ole mukana malleissa. Osa näistä tekijöistä on mitattavia suureita ja osa ei. Lisätutkimukselle on edelleen tilaa tällä alueella. Tämä työ vahvistaa edelleen käsitystä, että konvertteriprosessi on monimutkainen. Huomattiin, kuten aina prosessikehityksessä, että jatkuvaa kehitystyötä pitää tehdä prosessiolosuhteiden, raaka-aineiden ja ajopraktiikoiden muutosten huomaamiseksi. Muuten parannusten ja mallien antama hyöty heikkenee. Monitorointijärjestelmään olisi mahdollista kehittää rutiineja ja varoituksia operaattorien avuksi, jotta he huomaisivat järjestelmävirityksen tarpeen. Monitorointijärjestelmä toisi taloudellista hyötyä, mm. lisäpuhallusten vähentymisen, lopputuotteen paremman saannon ja laadun muodossa. Raaka-ainesäästöjä voidaan saavuttaa prosessin ohjattavuuden parantuessa. Monitorointijärjestelmän sisältäessä sääntötietokannan, se luo hyvän pohjan uusille työntekijöille tutustua prosessiin ja näin heidän koulutuksensa onnistuisi helpommin
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Köchy, Martin, and Sven Bråkenhielm. "Separation of effects of moderate N deposition from natural change in ground vegetation of forests and bogs." Universität Potsdam, 2008. http://opus.kobv.de/ubp/volltexte/2008/1662/.
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The effect of moderate rates of nitrogen deposition on ground floor vegetation is poorly predicted by uncontrolled surveys or fertilization experiments using high rates of nitrogen (N) addition. We compared the temporal trends of ground floor vegetation in permanent plots with moderate (7–13 kg ha−1 year−1) and lower bulk N deposition (4–6 kg ha−1 year−1) in southern Sweden during 1982–1998. We examined whether trends differed between growth forms (vascular plants and bryophytes) and vegetation types (three types of coniferous forest, deciduous forest, and bog). Trends of site-standardized cover and richness varied among growth forms, vegetation types, and deposition regions. Cover in spruce forests decreased at the same rate with both moderate and low deposition. In pine forests cover decreased faster with moderate deposition and in bogs cover decreased faster with low deposition. Cover of bryophytes in spruce forests increased at the same rate with both moderate and low deposition. In pine forests cover decreased faster with moderate deposition and in bogs and deciduous forests there was a strong non-linear increase with moderate deposition. The trend of number of vascular plants was constant with moderate and decreased with low deposition. We found no trend in the number of bryophyte species. We propose that the decrease of cover and number with low deposition was related to normal ecosystem development (increased shading), suggesting that N deposition maintained or increased the competitiveness of some species in the moderate-deposition region. Deposition had no consistent negative effect on vegetation suggesting that it is less important than normal successional processes.
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Dorrien, Christian F. von. "Ökologie und Respiration ausgewählter arktischer Bodenfischarten = Ecology and respiration of selected Arctic benthic fish species /." Bremerhaven : Alfred-Wegener-Inst. für Polar- und Meeresforschung, 1993. http://www.gbv.de/dms/bs/toc/127460144.pdf.
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Barron, II Joseph Charles. "Bog Turtle Distribution in Virginia: Assessing Proposed Methods for Finding New Localities and Examining Movement Between Wetlands." Thesis, Virginia Tech, 2021. http://hdl.handle.net/10919/104160.
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Freshwater turtles are among the most threatened groups of taxa globally, and the bog turtle, Glyptemys muhlenbergii is among the most imperiled in North America. In Virginia, USA, bog turtles are restricted to occupying Appalachian Mountain fens. Fens are naturally small and fragmented wetlands characterized by elevated water tables and an open canopy. Although there is a strong need to document and monitor populations of bog turtles, efforts to do so are often limited by the low detection of the species. The first objective of this thesis was to assess proposed methodologies for locating populations of turtles on the landscape. My first chapter assessed a previously-developed habitat distribution model for bog turtles using an occupancy modeling approach. I conducted 216 surveys of 49 discretely predicted patches of habitat, recording conditions such as weather, size of wetland and time of year, hypothesized to affect detection during each survey. In addition, I assessed factors including stream entrenchment, grazing presence and surrounding impervious surfaces for each surveyed patch to identify data sources that could improve future models or better assess sites. I found that sites with larger total wetland area had higher detection per survey, possibly due to larger sites having higher densities of turtles (among other explanations), and that sites with higher amounts of impervious surfaces within their drainage were less likely to be occupied.
In addition to the bog turtle, several plant species also occur in mountain fens. These species usually have a locally rare distribution or are disjuncts from a more northern latitude. Because of these traits, a high diversity of specialist plants may be indicative of a fen with a robust hydrology that has historically been less disturbed. Past site quality analyses have proposed using indicator diversity to assess sites, but no study has found if these species to tend to co-occur. My second chapter examines this hypothesis. I first chose a list of plant species that would most likely have habitat requirements similar to those of turtles. Then, at 12 sites, 6 with turtles and 6 without, I conducted a complete floral inventory. I first tested community-wide differences between the floral communities of these sites and found no difference, but when I narrowed my analysis to examining occurrence patterns of plant species determined a priori to be fen specialists and Glyptemys muhlenbergii, a pattern of co-occurrence was found. This lends support to the idea that indicator plants could be used as a tool to better evaluate sites that may have bog turtles.
My last chapter investigated movement of bog turtles in a landscape impacted by anthropogenic development. Movement of turtles between adjacent sites is critical to maintaining genetic diversity and maintaining metapopulation integrity. Despite this importance, records of long distances movements among wetlands are scarce in the literature, likely due to the lack of long-term studies for areas with multiple adjacent sites. In Virginia, mark recapture monitoring has been done intermittently in a cluster of sites for over 32 years. To determine the prevalence of movement among sites for bog turtles, I examined the dataset for all instances of turtles found at sites different from their last capture. I calculated the straight-line distance for each recorded movement. I also examined the sex of the turtle to test whether sex influences movement the frequency and distance of movements. For a subset of movements, I calculated least-cost pathways to identify possible barriers to movement using a previously published resistance model. I found 21 instances where a turtle was caught at a different site than its last capture over 32 years of monitoring. Neither sex was more likely to move farther than the other. Although the study's observed rate of movement may appear low, it is likely an underestimate when detection and asymmetric sampling are taken into account. The least cost pathways analysis suggested that roads or driveways were likely crossed for a significant portion of movement events. Finally, to examine how movement may be affecting the current distribution of bog turtles, I described a method to test whether adjacency to known populations influences the probability of a new site being occupied by turtles. I prove the utility of the method by applying it to a map of bog turtle occurrences collected over this study and show that it can account for habitat differences and barriers to movement between sites as well. In spite of plausibility of the method, limitations in how occurrence data are currently collected prevent its immediate application.
Together, this thesis will help managers not only find and assess wetlands on the landscape, it will also provide information about the network of connected patches on the landscape. Knowing where bog turtles are and what wetlands or sub-populations are potentially connected will allowed for a more directed and informed regional management strategy.Master of Science
Freshwater turtles are facing population declines worldwide, and the bog turtle Glyptemys muhlenbergii is among the most imperiled in North America. Bog turtles occupy naturally small, specialized wetlands called Appalachian Mountain fens. The prevalence of fens on the landscape has declined over recent decades due to agricultural practices. Although there is a strong need to document and monitor bog turtle populations due to their threatened status, bog turtles are difficult to find due to their small size and ability to burrow completely into substrate. Thus, considerable effort must be expended to find populations and track their status. The first overall objective of this thesis was to assess methods for locating populations of bog turtles. My first chapter tests a habitat distribution model that uses publicly available landscape data such as topopgraphy and land cover to predict areas likely to contain turtles. To do this, I systematically surveyed 49 predicted sites multiple times each over 2 years. Simultaneously, I recorded variables such as the time of year, size of the wetland and the weather to determine whether any factor significantly explained the ability to find turtles on any given survey. In addition, I was able to record several variables relating to wetland quality and isolation that were not in the initial model. I found that larger wetlands were easier to search than smaller wetlands, possibly due to larger sites having more turtles, and that wetlands near more impermeable surfaces (such as roads and buildings) were less likely to have bog turtles. As another potential method to find bog turtles and assess sites, we tested the use of 'pristine indicator' plants as a metric for potential wetlands. Mountain fens have specific attributes, such as high groundwater influence and exposure to a large amount of sunlight. Several species, including the bog turtle, are specialized to these factors and are rarely found in the surrounding landscape. Because a distinct community exists for mountain fens in this region, sites with a higher diversity of fen specialist plants may be indicative of a higher quality site which can support more specialists, including the bog turtle. My second chapter tests this hypothesis. I first chose a list of species that would most likely have habitat requirements similar to those of bog turtles. Then, at 12 sites I documented every plant species I encountered within the wetland. I compared the plant community as a whole between bog turtle-occupied and unoccupied sites and found no significant difference between the two. When I narrowed my analysis to focus on plants I previously identified as sharing habitat requirements with the bog turtle, I found a strong pattern of their co-occurrence with bog turtles. This lends support to the idea that these 'pristine indicator' plants could be used as a tool to better evaluate sites that may have bog turtles. My last chapter investigates movement of bog turtles in a landscape impacted by human development. Movement of turtles between adjacent wetlands is critical to maintaining long term regional viability of the species, as it lets turtles colonize new sites and exchange genes. Despite the importance of these movements, records of turtles moving long distances between two wetlands is scarce in the literature, likely due to the lack of long-term studies for areas with multiple adjacent wetlands. One method of recording movements is by marking turtles with a unique ID and recording where it was encountered as wetlands are surveyed on the landscape. In Virginia, this procedure has been conducted at multiple sites over 32 years. To understand the prevalence of movement between sites for this species, I examined this dataset and examined all instances of a turtle being found at a site different from its last capture. I recorded the straight-line distance moved for each recorded movement as well as the sex of the turtle, to test if either sex was more or less likely to undertake these movements. Then, for a subset of movements, I calculated least-cost pathways, a metric that accounts for landscape features and plots the easiest route for turtles to move. This way, I could evaluate the prevalence of barriers to movement, such as roads or development, on the landscape. I found 21 documented movements among sites over 32 years of monitoring. Neither sex was more likely to move further than the other. Compared to studies looking at other freshwater turtles, the observed rate of movement appeared low, but this was likely an underestimate due to the difficulty of capturing specific individuals. I also found evidence of significant barriers to movement in 13 out of 17 evaluated least-costs paths, usually roads or driveways. Finally, to examine how movement affects bog turtle distribution, I describe a methodology of testing if adjacency to known populations influences the probability of a new site being occupied by turtles. I demonstrate the plausibility of the method by applying it to a map of occurrences collected over this study and show that it can account for habitat differences and barriers to movement between sites as well. However, limitations in my sampling scheme limit conclusions from my dataset. Together, these findings will help future managers find where turtles are and which sites may be connected. These results will help managers make more informed decisions for managing bog turtles at a statewide level.
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Nurhayati, Niknik. "Identification, molecular cloning and characterisation of homospermidine synthase and deoxyhypusine synthase from Phalaenopsis and Crotalaria species /." Göttingen : Cuvillier, 2004. http://www.gbv.de/dms/bs/toc/385141416.pdf.
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Forell, Burkhard. "A methodology to assess species yields of compartment fires by means of an extended global equivalence ratio concept." Braunschweig : Techn. Univ., Inst. für Baustoffe, Massivbau und Brandschutz, 2007. http://www.gbv.de/dms/bs/toc/527844802.pdf.
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Odounga, Bernard. "Etude de la fissuration des bois tropicaux par mesures des champs." Thesis, Université Clermont Auvergne (2017-2020), 2018. http://www.theses.fr/2018CLFAC015/document.
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L’objectif du présent travail est d’étudier expérimentalement et numériquement la fissuration des bois tropicaux issus de la forêt gabonaise, à savoir : le Milicia excelsa (iroko),l’ Aucoumea klaineana pierre (okoumé) et Pterocarpus soyauxii (padouk). Cette étude est axée sur le processus de croissance de la fissure en mode d’ouverture et en mode mixte des trois essences à l’aide d’éprouvettes Compact Tension Shear (CTS) et Mixed Mode CrackGrowth (MMCG) modifiées. Les éprouvettes sont montées dans un système Arcan et placées dans une machine d’essai électromécanique. La méthode de la grille est utilisée pour mesurer les champs de déplacements et de déformations au voisinage de la fissure. Ces cartes ainsi obtenues permettent d’obtenir l’ouverture et la longueur de la fissure tout au long de l’essai. Les courbes force en fonction de l’ouverture de la fissure sont déduites des mesures. La méthode de la complaisance à déplacement imposé est utilisée pour calculer le taux de restitution d’énergie G en mode d’ouverture de fissure et en mode mixte. Les résultats ont montré un effet de l’épaisseur sur la fissuration. Ces résultats ont aussi permis de mettre en évidence une proportionnalité de la densité par rapport aux paramètres de rupture de ces essences. En mode mixte les valeurs de l’évolution de G sont présentées en fonction de la longueur de fissure après découplage des modes (séparation du mode 1 et du mode 2). On observe pour l’okoumé par exemple, que les rapports des taux de restitution d’énergie des deux modes sont constants, ce qui justifie le caractère intrinsèque des paramètres de fissuration obtenus. Des comparaisons faites avec les résultats issus de de la littérature sur les essences tempérées de même densité ont montré des similitudesThe objective of the present work is to study experimentally and numerically the crackingbehavior of tropical woods from the Gabonese forest, namely : Milicia excelsa (iroko), Aucoumeaklaineana pierre (okume) and Pterocarpus soyauxii (padouk). This study focuseson the crack growth process in crack opening mode and mixed mode of these three speciesusing Modified Tension Shear (CTS) and Mixed Mode Crack Growth (MMCG) specimens.The specimens are mounted in an Arcan system and placed in an electromechanical testingmachine. The grid method is used to measure the displacement and strains fields near the tipcrack. These maps make it possible to obtain the opening and the length of the crack duringthe tests. The curves force showing the face as a function of the crack opening are deducedfrom the measurements. The experimental critical energy release rate G is evaluated by thecompliance method in imposed displacement. The results show an effect of the thickness oncracking. These results also made it possible to demonstrate a proportionality of the densitywith the parameters of rupture of these species. In mixed mode, after decoupling the modes(separation of mode 1 and mode 2), the values of G are presented as a function of to the cracklength. For Okume, for example, it was observed that the ratios of the energy release ratesof the two modes are constant, which justifies the intrinsic character of the cracking parameterswere obtained. Comparisons made with results from the literature review on temperatespecies of the same density showed similarities
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Dyck, Barbara S. "The species composition, aboveground biomass and carbon content of vegetation in two basin bogs in the Experimental Lakes area, north-western Ontario." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1998. http://www.collectionscanada.ca/obj/s4/f2/dsk2/ftp01/MQ32097.pdf.
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Goedhart, Christian Leonard. "Influence of osmotic stress, ethanol, and a substituted pyridazinone, BAS 13-338, on the growth and lipid composition of two Chlorella species." Diss., Virginia Polytechnic Institute and State University, 1987. http://hdl.handle.net/10919/53634.
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Chlorella vulgaris and Chlorella pyrenoidosa were compared relative to their abilities to grow at osmotic potentials of -0.1, -0.5, -1.0, -1.5, -2.0 MPa, [polyethylene glycol(PEG)-induced], and for osmotically-induced changes in lipid composition. C. vulgaris growth was inhibited as osmotic potentials decreased, while C. pyrenoidosa growth was moderately inhibited at -2.0 hPa. C. vulgaris produced increasing concentrations of triglycerides and sterol esters and decreasing levels of polar lipids and sterols as osmotic concentrations increased. Polar lipids, triglycerides, and sterols declined in C. pyrenoidosa while steryl esters remained constant. Ratios of free sterols to polar lipids were 10-fold greater in C. pyrenoidosa and were unaffected by reduced osmotic potentials. In C. vulgaris the sterol to polar lipid ratio declined.
Decreasing osmotic potentials in a continuous culture of C. vulgaris, lowered cell lipid concentration, and had no effect on chlorophyll concentrations. The greatest decrease occurred as the osmotic potential decreased from -0.1 to -0.5 HPa. Decreasing osmotic potential caused the phospholipid concentrations to decline. Saturation of triglycerides and free fatty acids increased and decreased, respectively, while polar lipids remained fairly constant. However, the sterol to phospholipid ratio increased as the osmotic potential was lowered.
BAS 13-338 (4-chloro-5-(dimethylamino)-2-phenyl-5- 3(2H)pyridazinone) had no effect on C. vulgaris resistance to osmotic stress, but caused growth inhibition as concentrations increased. However, BAS 13-338 was effective in decreasing growth inhibition of C. vulgaris grown in inhibitory levels of ethanol. BAS 13-338 had differing effects on the lipid composition of C. vulgaris when grown in PEG at an osmotic potential of -1.5 MPa compared to -0.1 MPa with 0.33% ethanol. The greatest effects were observed in the ethanol treatments where the qualitative composition of precursor sterols increased as the level of BAS 13-338 increased.
This investigation confirmed the important role of lipids in responding to environmental stress through observations of lipid responses to osmotic stress and by manipulation of lipid concentrations using BAS 13-338. Resistance to ethanol inhibition but not osmotic inhibition was achieved in the investigation.Ph. D.
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Kurbjeweit, Frank. "Reproduktion und Lebenszyklen dominanter Copepodenarten aus dem Weddellmeer, Antarktis = Reproduction and life cycles of dominant copepod species from the Weddell Sea, Antarctica /." Bremerhaven : Alfred-Wegener-Inst. für Polar- und Meeresforschung, 1993. http://www.gbv.de/dms/bs/toc/128903694.pdf.
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Makio, Haruyuki. "A Study of Active Species and Stereo-, Regio-, and Substrate- Selectivity in Olefin Polymerization Mediated by Bis(salicylaldiminato) Group 4 Transition Metal Catalysts." 京都大学 (Kyoto University), 2011. http://hdl.handle.net/2433/142259.
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Mvogo, Jean Kisito. "Regroupement mécanique par méthode vibratoire des bois du bassin du Congo." Thesis, Bordeaux 1, 2008. http://www.theses.fr/2008BOR13790/document.
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L’objet de ce travail de thèse est le regroupement des essences bois du bassin du Congo en quatre groupes en fonction de la similitude de leurs propriétés mécaniques essentielles. Le module d’élasticité (MOE), propriété indicatrice, est estimé par une méthode non destructive : l’essai vibratoire. Pour chaque classe, le fractile à 5% d’exclusion supérieur d’une propriété mécanique est calculé à partir d’une théorie clairement exposée. Le bassin du Congo est un patrimoine en danger à cause des pressions anthropiques au premier rang desquelles figure la coupe hyper sélective des essences bois. Le résultat de ce regroupement permet de proposer comme substitut aux essences menacées d’extinction des essences aux propriétés mécaniques similaires plus disponibles en terme de ressources sur pied. D’où la contribution à la gestion durable et au maintien de la biodiversité du bassin du Congo. On montre que le MOE vibratoire est quasi-invariant avec la teneur en eau et qu’il est bien corrélé au MOE statique, à la masse volumique et à la contrainte à la rupture. C’est donc un bon prédicteur du module de rupture (MOR) à 12% du taux d’humidité du bois vert. Ceci valide l’organisation en groupe d’essences réalisée dans ce travail. Les valeurs caractéristiques des propriétés mesurées sont calculées pour chaque classe. Parce que l’Eurocode 5 exige que les bois utilisés en structure soient classés, nous proposons, in fine, un système de classement en structure des bois du bassin du Congo voué à une meilleure utilisation des forêts pour la conservation des écosystèmes forestiers et la satisfaction des besoins fondamentaux de l’hommeThis Ph.D. work deals with a non-destructive experimental approach organizing the species of the Congo basin in four groups according to the likeness of their main mechanical properties, and to guarantee for each group the 5th percentile characteristic value of mechanical properties such as the modulus of elasticity (MOE). For the sustainable management of forest and conservation of exotic biodiversity of the Congo basin, it is necessary to promote the exploitation of less-consumed species with equivalent mechanical characteristics. The aim of the present work is to propose a scheme for grouping species with similar values of modulus of elasticity (MOE) obtained through vibratory method. Only small clear specimens are tested. The assignment of a given specie to one of the four groups takes place in return for a homogeneity test of comparison of the random variables of species to the random variable of the group. Results of the present grading show that some species can be interchangeably consumed in the construction industry and that the procedure must include more species of the Congo basin. This property grouping will facilitate substitution of underutilized species for ones that are being more exploited. Thus, wood designers and constructors might have a wide variety of choices in their decision-making while promoting less-consumed species and reducing the demand of traditionally most wanted extinguishable species. The MOE obtained by intrinsic vibration of wood versus is not influenced by moisture content. So, the non destructive method bases on longitudinal vibrations can be used in industrial production of timber to certify the modulus of rupture (MOR) at 12% moisture content of green wood by direct correlation. Finally, we propose a grading system of tropical wood
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Saha, Tchinda Jean-Bosco. "Caractérisation et valorisation des substances extractibles de cinq essences camerounaises majeures de l'industrie du bois : Ayous, Moabi, Movingui, Padouk et Tali." Thesis, Université de Lorraine, 2015. http://www.theses.fr/2015LORR0113/document.
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Au cours de ce travail, le taux d’extractibles de cinq essences camerounaises a été évalué par la technique d’extraction accélérée ASE 200 et au Soxhlet. Le taux d’extractibles varie de 4,4 à 17,7%. Le screening des extraits a révélé la présence de polyphénols, de saponines, de flavonoïdes, de stérols et de terpènes. Les phénols totaux contenus dans les extraits ont été évalués par la méthode de Folin–Ciocalteu en utilisant l’acide gallique comme standard. La teneur varie de 16,5 à 165,83 mg éq acide gallique / g d’extrait. Le dosage des tannins condensés par la méthode colorimétrique a permis de montrer que ces derniers varient de 0,15 à 23,61 g cyanidin équivalents / 100 g de matière sèche. L’identification des composés contenus dans les extraits par GC-MS a permis d’identifier de l’homopterocarpine et de la pterocarpine dans les extraits de padouk. Les extraits de tali contiennent de la catéchine, l’acide gallique et du pyrogallole. L’acide gallique, le squalène et les triterpènes sont les composés majoritairement identifiés dans les extraits de movingui. La durabilité naturelle des bois a été évaluée par la norme européenne EN 350-1, 1994. Il ressort que les pertes de masse deviennent plus importantes lorsque les éprouvettes de bois ont été extraites. La perte de masse des éprouvettes non extraites varie de 0,1 à 59% (le hêtre a été pris comme référence). Les essais d’inhibition de croissances sur les champignons de pourriture ont montré qu’à des concentrations de 250 ppm, nos extraits étaient fongistatiques et qu’à des concentrations de 500 ppm certains extrait étaient fongicides (extrait de tali). L’évaluation des propriétés antioxydante et colorante des extraits pour envisager de potentielles applications industrielles a été effectuée. Le pouvoir antioxydant des extraits a été évalué par la méthode d’inhibition du linoléate de méthyle induite par l’azobisisobutyronitrile (AIBN). Les résultats obtenus sont satisfaisants car l’activité antioxydante varie de 10 à 86%. Le pouvoir anti-radicalaire des extraits a été évalué en utilisant le radical 2,2-diphényl-1-picrylhydrazyl (DPPH.). Les concentrations nécessaires pour consommer 50% du radical varie de 2,7 à 60,5 mg/L. La capacité des extraits aqueux et alcalins à teindre les fibres naturelles et artificielles a été évaluée. La mesure de la coloration prise par les fibres s’est faite à l’aide d’un colorimètre Datacolor D65°10. Les résultats montrent que ces extraits donnent une coloration jaune avec les extraits de movingui et une coloration rouge avec les extraits de padouk. L’utilisation des extraits pour inhiber la croissance bactérienne a montré que les extraits étaient bactériostatiques pour les concentrations testéesIn this work, the accelerated technical ASE 200 and Soxhelet was used to evaluate the amount of extractives contained in five Cameroonian wood species. The amount of extractives ranged from 4.4 to 17.7% with respect to oven-dry matter. Phytochemical screening of the extractives revealed the presence of polyphenols, saponins, flavonoïds, sterols and terpenes. The total phenolic content of the extracts was measured by the Folin-Ciocalteu method using gallic acid as standard. The phenolic content ranged from 16.5 to 165.83 mg eq gallic acid/g of extract. The condensed tannins, evaluated by colorimetric method, ranged from 0.15 to 23.61 g cyanidin equivalents/100 g of dry matter. GC-MS identified the homopterocarpine and pterocarpin as major compound in extracts of padouk. Catechin, gallic acid and pyrogallole were the major compounds found in the extracts of tali. Extracts of movingui consisted mainly of diterpenes and several compounds not readily identifiable. Gallic acid, squalene and triterpenes were the predominant compounds identified in the extracts of movingui. The natural durability of wood was evaluated using the European Standard EN 350-1. Mass losses increased when the wood samples were extracted. Mass losses of non-extracted samples ranged from 0.1 to 59% (with beech taken as a reference). The effect of extractives on fungal growth showed that at 250 ppm concentrations, the extracts were fungistatic and that at 500 ppm concentrations, the extracts of tali were fungicidal.Valorization of the extractives in the food and the textile industries was attempted. In food, the antioxidant activity of the extracts by inhibition of methyl linoleate induced by AIBN was evaluated. The results obtained were satisfactory because all the extracts showed antioxidant activity which varied from 10 to 86%. Then the anti-radical capacity of our extracts was assessed by the DPPH method. The concentration necessary to consume 50% of DPPH varied from 2.7 to 60.5 mg/L. Aqueous and alkaline extracts were used to dye natural and artificial fibers. The coloration taken by the fibers was measured using a Datacolor D65°10 apparatus. These extracts gave a yellow color with extracts of movingui and a red color with extracts of padouk. The effect of extractives on bacteria growth showed that the extracts were bacteriostatic at the tests concentrations
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Pucker, Boas [Verfasser]. "De novo Nd-1 genome assembly reveals genomic diversity of Arabidopsis thaliana and facilitates genome-wide non-canonical splice site analysis across plant species / Boas Pucker." Bielefeld : Universitätsbibliothek Bielefeld, 2019. http://d-nb.info/1188812432/34.
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Rahayu-Sekartiing, Istie. "Characteristics of lathe check and surface roughness of fast growing wood veneers and their performance on laminated veneer lumber." Thesis, Paris, ENSAM, 2016. http://www.theses.fr/2016ENAM0034/document.
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Pour répondre à la demande croissante de bois et pour préserver les forêts primaires, les méthodes de sylviculture les plus dynamiques ont été privilégiées de manière générale sur la planète.. Les objectifs de la recherche étaient 1) déterminer le point de démarcation/ âge de transition entre le bois juvénile et le bois mature sur sengon (Falcataria moluccana), jabon(Anthocephalus cadamba Miq.), peuplier (Populus sp) et douglas (Psedotsuga menziesii); 2) analyser l'effet de la juvénilité sur un fissuration cyclique, la rugosité et de mouillage; 3) analyser l'effet de la fissuration cyclique et juvénilité sur la résistance à l'adhérence de la colle et les propriétés mécaniques du LVL en flexion; et 4) appliquer un nouveau modèle analytique pour estimer la variation du module d'élasticité du lamibois (sengon et jabon) depuis la moelle vers l'écorce. A partir de la longueur des fibres, le point de démarcation entre le bois juvénile et le bois mature ont été estimés. Pour les essences sengon and jabon, les placages obtenus à partir du cœur des arbres, réputés juvéniles, sont plus fissurés plus rugueux et avec une haute mouillabilité comparativement à ceux obtenus à partir du bois près de l’écorce (plus mature). Une phase d’étuvage préliminaire des bois dans un bain d’eau chaude à 75°C pendant 4 heures a permis d’améliorer sensiblement la qualité des placages en diminuant la fissuration, la rugosité et s’accompagne d’une augmentation de la mouillabilité. La résistance à l'adhérence de la colle, et les modules élastiques et de rupture spécifiques (SMOE et SMOR) du LVL (jabon et sengon) diminuent à mesure que la fréquence de fissure augmente ou en partant de l'écorce vers la moelle. L'avantage de l'utilisation de placages en peuplier de bois mature a été prouvé avec une amélioration de 15 à 20% en moyenne pour les propriétés mécaniques, pour un poids de panneau comparable. Pour le douglas, l'utilisation de placages de bois mature dans la constitution des panneaux de LVL permet également d’améliorer les performances en flexion (de 7 à 22 % sur el MOR). Le modèle analytique a été utilisé afin de prédire les variations du module élastique allant de la moelle à l’écorce. Il permet à partir d’un grand nombre de combinaisons d’estimer le potentiel issu d’une ressource donnée. Pour le contexte de l’étude qui représente bien le potentiel sylvicole de l’Indonésie, la proportion de bois juvénile étant quasi-totale (100%), l’action de trier les placages n’est pas apparue comme pertinenteThe development of plantation and community forest to meet wood demand in society has produced fast growing wood species. The research objectives were 1) to determine demarcation point/transition age between juvenile and mature wood on sengon (Falcataria moluccana), jabon (Anthocephalus cadamba Miq.), poplar (Populus sp) and douglas fir (Psedotsuga menzii); 2) to analyze the effect of juvenility on lathe check, surface roughness and wettability; 3) to analyze the effect of lathe check and juvenility on glue bond strength and laminated veneer lumber (LVL) bending properties; and 4) to apply a new analytical model to determine the variation of specific MOE LVL values of sengon and jabon from pith to bark. Based on fiber length trait, the demarcation point between juvenile and mature wood were approximately at segmented rings 17th (sengon) and at segmented ring 24th (jabon). While, transition age of poplar cultivars and douglas-fir, transition age happened approximately at 12 years old and 18 years old, respectively. The results showed that wood near pith on sengon and jabon resulted veneers with higher lathe check, rougher surface and high wettability, while wood near bark resulted veneers with lower lathe check, smoother surface and low wettability. Glue bond strength, Specific MOE (SMOE) and Specific MOR (Modulus of Rupture) of sengon and jabon LVL were decreased as the frequency of lathe check increased or those strength values increased from pith to bark. The advantage of using poplar veneers from mature wood was proved with an improvement of 15 to 20% on average for mechanical properties, while for douglas-fir, was 7 to 22%. An analytical model was used to predict the variation of the LVL mechanical characteristics using different scenarios. According to the context of this study assumed to be close to the Indonesian resource there is no need to sort veneers since most of the tree is juvenile wood for logs no older than 7
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Belyaeva, Maria [Verfasser]. "Effects of multiple abiotic stressors on the species and genetic biodiversity of littoral Cladocera in two types of acidic habitats in Germany: hard-water mining lakes and soft-water bog lakes / Maria Belyaeva." Aachen : Shaker, 2013. http://d-nb.info/1049382838/34.
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Anjos, Jeniffer Natalie Silva dos. "Desenvolvimento regional da área de livre comércio de Boa Vista e suas implicações socioespaciais a partir de um estudo geoestratégico." Universidade Federal de Roraima, 2014. http://www.bdtd.ufrr.br/tde_busca/arquivo.php?codArquivo=251.
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Coordenação de Aperfeiçoamento de Pessoal de Nível SuperiorCom o objetivo de construir um estudo sobre a Área de Livre Comércio de Boa Vista a partir da política de integração regional para a Amazônia Ocidental, a presente pesquisa discorre sobre os aspectos de interdependência na composição das esferas intra-regionais e inter-regionais resultantes das ações de regionalização programadas pelo Estado nacional para as áreas que apresentam diferenças regionais impactantes na sua economia em comparação as demais regiões brasileiras. Com base nas leis de criação e regulamentação da área de livre comércio de Boa Vista a pesquisa se fundamenta na concepção de ações políticas para o desenvolvimento das áreas localizadas em circuitos econômicos inferiores e dependentes de escalas com economias especializadas. Fundamentando-se no conceito de políticas de desenvolvimento regional a cidade Boa Vista é avaliada como local receptor de ações estatais impostas a nível hierárquico. Nessas condições o regime aduaneiro especial do tipo área de livre comércio é avaliado como uma política de integração e de desenvolvimento regional fracassada, apresentando não mais que uma ação compensatória ao desgaste e inércia econômica do estado de Roraima. Estabelecidas sobre as alternativas de desenvolvimento pulverizadas pelo Estado e pelas elites regionais as tímidas transformações socioeconômicas na cidade não resultam da eficácia do modelo de desenvolvimento proposto para a Amazônia e em especial para Boa Vista.
Aiming to introduce a study about the Trade free Area in Boa Vista -RR from the regional integration policy for the Western Amazon perspective, this research discusses the aspects of interdependence in the composition of intra - regional and inter - regional levels resulting from actions regionalization programmed by the national government for the areas that present striking regional differences in its economy compared to other Brazilian regions. Based on the laws of creation and regulation of the free trade area of Boa Vista, this research is based on the design of policies for the development of areas located in lower economic circuits and dependent of scales with specialized economies. Basing on the concept of regional development policies the city of Boa Vista is evaluated as receptor of State actions imposed in a hierarchical level. Under these conditions the special customs regime of free trade area type is reported as an integration policy and failed regional development, presented no more than a compensatory action due the economic inertia and inroad of the state of Roraima. Established on alternative of development sprayed by state and regional elites, little socioeconomic transformations in the city do not result in the efficiency of development model proposed for the Amazon and in particular for Boa Vista.
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Belmerhnia, Leïla. "Approches parcimonieuses pour la sélection de variables et la classification : application à la spectroscopie IR de déchets de bois." Thesis, Université de Lorraine, 2017. http://www.theses.fr/2017LORR0039/document.
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Le présent travail de thèse se propose de développer des techniques innovantes pour l'automatisation de tri de déchets de bois. L'idée est de combiner les techniques de spectrométrie proche-infra-rouge à des méthodes robustes de traitement de données pour la classification. Après avoir exposé le contexte du travail dans le premier chapitre, un état de l'art sur la classification de données spectrales est présenté dans le chapitre 2. Le troisième chapitre traite du problème de sélection de variables par des approches parcimonieuses. En particulier nous proposons d'étendre quelques méthodes gloutonnes pour l'approximation parcimonieuse simultanée. Les simulations réalisées pour l'approximation d'une matrice d'observations montrent l'intérêt des approches proposées. Dans le quatrième chapitre, nous développons des méthodes de sélection de variables basées sur la représentation parcimonieuse simultanée et régularisée, afin d'augmenter les performances du classifieur SVM pour la classification des spectres IR ainsi que des images hyperspectrales de déchets de bois. Enfin, nous présentons dans le dernier chapitre les améliorations apportées aux systèmes de tri de bois existants. Les résultats des tests réalisés avec logiciel de traitement mis en place, montrent qu'un gain considérable peut être atteint en termes de quantités de bois recycléesIn this thesis, innovative techniques for sorting wood wastes are developed. The idea is to combine infrared spectrometry techniques with robust data processing methods for classification task. After exposing the context of the work in the first chapter, a state of the art on the spectral data classification is presented in the chapter 2. The third chapter deals with variable selection problem using sparse approaches. In particular we propose to extend some greedy methods for the simultaneous sparse approximation. The simulations performed for the approximation of an observation matrix validate the advantages of the proposed approaches. In the fourth chapter, we develop variable selection methods based on simultaneous sparse and regularized representation, to increase the performances of SVM classifier for the classification of NIR spectra and hyperspectral images of wood wastes. In the final chapter, we present the improvements made to the existing sorting systems. The results of the conducted tests using the processing software confirm that significant benefits can be achieved in terms of recycled wood quantities
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Belyaeva, Maria [Verfasser], and Brigitte [Akademischer Betreuer] Nixdorf. "Effects of multiple abiotic stressors on the species and genetic biodiversity of littoral Cladocera in two types of acidic habitats in Germany : hard-water mining lakes and soft-water bog lakes / Maria Belyaeva. Betreuer: Brigitte Nixdorf." Cottbus : Universitätsbibliothek der BTU Cottbus, 2013. http://d-nb.info/1045604127/34.
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Nickel, Jörg. "Bentho-pelagische Kopplungsprozesse im arktischen Mellemfjord (Westgrönland) unter besonderer Berücksichtigung benthischer Peracarida (Malacostraca, Crustacea) = Benthic-pelagic coupling in the Arctic Mellemfjord (West-Greenland) with special focus on benthic Peracarida (Malacostraca, Crustacea) /." Bremerhaven : Alfred-Wegener-Inst. für Polar- und Meeresforschung, 2004. http://www.gbv.de/dms/bs/toc/470608676.pdf.
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Lütkemeier, Thomas. "Chez soi - the aesthetic self in Arthur Schopenhauer, Walter Pater and T.S. Eliot : a study in the aesthetic theories of Schopenhauer, Pater and Eliot, with special regard to notions of selfhood, time and influence /." Würzburg : Königshausen & Neumann, 2001. http://www.gbv.de/dms/bs/toc/331784688.pdf.
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Silva, Gabriela Bueno Bittencourt. "Comunidades de Anf?bios Anuros Insulares do Litoral Sudeste do Brasil: Composi??o Taxon?mica e Rela??es com a Hist?ria de Forma??o das Ilhas." Universidade Federal Rural do Rio de Janeiro, 2011. https://tede.ufrrj.br/jspui/handle/jspui/1150.
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Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior, CAPES, Brasil.
BITTENCOURT-SILVA, Gabriela Bueno. Insular Anuran (Amphibia) Communities of the Southeast Coast of Brazil: Taxonomic Composition and Relationship to the History of the Islands. 2011. 72p. Dissertation (Master of Science in Animal Biology). Instituto de Biologia, Departamento de Biologia Animal, Universidade Federal Rural do Rio de Janeiro, Serop?dica, RJ, 2011. A data set containing a list of the known species of frogs that occur near shore and on eight islands of the south coast of the State of Rio de Janeiro and north of the State of S?o Paulo was produced. For that, I compiled data from the literature and conducted inventories of a few of the islands. This list included 67 anuran species belonging to 11 families for eight islands and 117 species and 14 families for two localities on the mainland. The pattern of richness between islands was analyzed in respect to the island area and the composition of habitats used by the anurans for reproduction. Insular structural complexity was also evaluated in this regard. The results of correlation analyses of area vs. species richness and species richness vs. number of reproductive habitats were highly significant indicating that species richness prediction in fragmented environments depends on both factors. Nestedness analyses using the metric NODF was performed in an attempt to investigate whether shared species absences among the islands are the result of a random process or represents a pattern indicative of ordered loss of species. The predicted pattern was confirmed ? that is, that species loss is nonrandom and that this was possibly caused by habitat loss. The role played by climatic events at the beginning of the Holocene and of the availability of reproductive habitats in the islands upon species loss is discussed. Furthermore, it is discussed how these results can help to guide conservation strategies of anuran species.
BITTENCOURT-SILVA, Gabriela Bueno. Comunidades de Anf?bios Anuros Insulares do Litoral Sudeste do Brasil: Composi??o Taxon?mica e Rela??es com a Hist?ria de Forma??o das Ilhas. 2011. 72p. Disserta??o (Mestrado em Biologia Animal). Instituto de Biologia, Departamento de Biologia Animal, Universidade Federal Rural do Rio de Janeiro, Serop?dica, RJ, 2011. Atrav?s de invent?rios e compila??o de dados da literatura levantou-se a composi??o de esp?cies de anf?bios anuros de oito ilhas, sendo seis da Costa Verde do Estado do Rio de Janeiro e duas do litoral norte do Estado de S?o Paulo. Al?m das ilhas, foram tamb?m compilados da literatura os invent?rios de duas comunidades representativas do litoral dos dois Estados. Adicionalmente, foram registradas 67 esp?cies, pertencentes a 11 fam?lias de anuros nas ilhas e 117 esp?cies e 14 fam?lias para o continente. O padr?o de distribui??o de riqueza das ilhas foi avaliado em rela??o ? ?rea das ilhas, ? composi??o de ambientes usados pelos anuros para reprodu??o e ? complexidade estrutural das ilhas. As an?lises de correla??o da riqueza de esp?cies vs. ?rea e riqueza de esp?cies vs. n?mero de ambientes reprodutivos apresentam resultados significativos, que s?o indicativos que a riqueza de esp?cies em ambientes fragmentados depende da intera??o de ambos os fatores. A fim de avaliar se as aus?ncias compartilhadas de esp?cies entre as ilhas ocorrem ao acaso ou encontram-se estruturadas, realizou-se uma an?lise de aninhamento com o aux?lio da m?trica NODF. O padr?o previsto foi confirmado e a perda de diversidade ? discutida em rela??o ? eventos clim?ticos do in?cio do Holoceno e ? disponibilidade de ambientes reprodutivos nas ilhas. Discute-se ainda como os resultados desse estudo podem servir para orientar programas de conserva??o de esp?cies de anf?bios anuros
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Azevedo, Tânia Maria Paula de. "A AVALIAÇÃO DA APRENDIZAGEM NO PROCESSO DE ESCOLARIZAÇÃO DE ALUNOS COM DÉFICIT INTELECTUAL NOS ANOS FINAIS DO ENSINO FUNDAMENTAL E DO ENSINO MÉDIO." Universidade Federal de Santa Maria, 2010. http://repositorio.ufsm.br/handle/1/6950.
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This work is inserted into the research Field of Special Education in the Pos-Graduation Program at Federal University of Santa Maria. The central issue was the
assessment of the learning of students with intellectual deficit in a school which advocate the inclusion of students with special education needs in the scholar
process. When evaluating the problem, the focus was the identification of how it is processed the learning evaluation of students with intellectual deficit included in classes of final years of Fundamental and Medium School in a public School at Santa Maria/RS by professors at different areas and also, the focus was to know the results
of evaluation of students in the investigated context. The study is characterized by a descriptive and exploratory approach by using the principles and procedures
prescribed at Case Study, as research methodology. Data were collected from interviews, scholar documents and records of pedagogic practices, converging in the
analysis of the assessment of the learning practice in the inclusion context. Countersigned the study, the inherent aspects to the assessment of the learning and the process of organization of Special Education, regarded in the scholar documents. The evaluation practices unchained by professors constituted units of analysis, at classes where there was students with intellectual deficit, one of them at Fundamental School and the other one at Medium School. The Good Practices in Special Education conducted the study, making a criteria for analysis and data interpretation, which result in the verifications that: the assessment of the learning for students with intellectual deficit is realized through differentiated strategies of evaluation level, of objectives and of the teaching; the student with intellectual deficit needs the teacher's mediation to accomplish the activities that demand the abstraction competence; the collaboration among the teachers of class and of the Special Education is facilitative of the learning and is fundamental in the articulation of the Inclusive Education.Esta dissertação insere-se na Linha de Pesquisa de Educação Especial do Programa de Pós-Graduação da Universidade Federal de Santa Maria. A temática central foi a avaliação da aprendizagem de alunos com déficit intelectual em escola que preconiza a inclusão de alunos com necessidades educacionais especiais no processo de escolarização. Ao problematizar a avaliação de alunos com déficit intelectual incluídos em turmas de anos finais do Ensino Fundamental e do Ensino Médio numa escola pública estadual do município de Santa Maria/RS, objetivou-se identificar como se processa a avaliação da aprendizagem desses alunos, realizada por professores de diferentes áreas nas turmas referidas e conhecer os resultados das avaliações dos alunos no contexto investigado. O estudo caracteriza-se pela abordagem descritiva e explanatória, utilizando-se dos princípios e procedimentos prescritos no Estudo de Caso, como metodologia de pesquisa. Os dados foram coletados a partir de entrevistas, documentos escolares e registros da prática pedagógica, convergindo na análise da prática da avaliação de aprendizagem, no contexto da inclusão. Referendaram o estudo os aspectos inerentes à avaliação da aprendizagem e o processo de organização da Educação Especial, contemplados nos documentos escolares. Constituíram unidades de análise as práticas avaliativas desencadeadas por professores, nas turmas onde havia alunos com déficit intelectual, sendo uma no Ensino Fundamental e outra no Ensino Médio. A referência das Boas Práticas em Educação Especial conduziu o estudo, consistindo critério para análise e interpretação dos dados, que resultam nas constatações de que: a avaliação da aprendizagem de alunos com déficit intelectual se efetiva através de estratégias diferenciadas ao nível da avaliação, dos objetivos e do ensino; o aluno com déficit intelectual necessita da mediação do professor para realizar as atividades que exijam a competência de abstração; a colaboração entre os professores de sala de aula e da Educação Especial é facilitadora da aprendizagem e fundamental na articulação da Educação Inclusiva.
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Guyot, Virginie. "Rôle de la diversité des arbres dans la régulation des populations d’insectes défoliateurs en forêts matures d’Europe." Phd thesis, Toulouse, INPT, 2015. http://oatao.univ-toulouse.fr/14458/1/guyot_partie_1_sur_2_2.pdf.
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Qui du phénomène de résistance (RA) ou de susceptibilité (SA) par association est prépondérant en milieu forestier ? En d’autres termes, la défoliation par les insectes herbivores est-elle moins (RA) ou plus (SA) importante sur des arbres hôtes situés en mélange comparés à des monocultures ? A cause des contraintes méthodologiques, les connaissances sur la relation diversité - résistance en forêts matures restent faibles. Pour répondre à cette question, nous avons utilisé le dispositif exploratoire du projet FunDivEUROPE. Sur un réseau de 209 parcelles forestières sélectionnées le long de deux gradients orthogonaux de richesse spécifique (d’une à cinq essences en mélange) et de latitude (de la forêt méditerranéenne à la boréale), nous avons évalué la défoliation des houppiers des arbres. A l’aide d’un échantillon constitué de onze essences différentes, nous avons démontré pour la première fois un patron global de diminution de l’herbivorie (RA) en forêts matures à travers l’Europe. Nous avons également comparé l’herbivorie des insectes dans des placettes constituées de chênes purs ou mélangés à d’autres espèces, placées en lisière ou à l’intérieur de petits bois présents dans les vallées et coteaux de Gascogne. Nous avons observé moins de dégâts foliaires sur les chênes entourés par des voisins hétérospécifiques, et nous avons montré que la magnitude de cette résistance (RA) était plus importante en lisière qu’à l’intérieur des bois. Enfin, nous avons testé cette hypothèse de RA sur une espèce d’herbivore invasif en Italie, le cynips du châtaignier. Basée sur la même approche méthodologique, notre étude a montré de plus faibles dégâts de galles sur les châtaigniers lorsque la richesse spécifique de la parcelle était élevée. Notre travail fournit donc de nouvelles preuves supportant l’hypothèse de RA à travers trois contributions originales : i) la RA existe en forêt mature, ii) quelle que soit l’espèce d’herbivore, iii) y compris sur des espèces exotiques. Ces résultats devraient avoir d’importantes implications pour la gestion des insectes herbivores en forêt puisque le maintien et l’amélioration de la diversité des essences représentent un outil prometteur pour prévenir les dégâts d’insectes.
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Fu, Rong. "Biochemical and Spectroscopic Characterization of Tryptophan Oxygenation: Tryptophan 2, 3-Dioxygenase and Maug." Digital Archive @ GSU, 2009. http://digitalarchive.gsu.edu/chemistry_diss/44.
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TDO utilizes b-type heme as a cofactor to activate dioxygen and insert two oxygen atoms into free L-tryptophan. We revealed two unidentified enzymatic activities of ferric TDO from Ralstonia metallidurans, which are peroxide driven oxygenation and catalase-like activity. The stoichiometric titration suggests that two moles of H2O2 were required for the production of one mole of N-formylkynurenine. We have also observed monooxygenated-L-tryptophan. Three enzyme-based intermediates were sequentially detected in the peroxide oxidation of ferric TDO in the absence of L-Trp including compound I-type and compound ES-type Fe-oxo species. The Fe(IV) intermediates had an unusually large quadrupole splitting parameter of 1.76(2) mm/s at pH 7.4. Density functional theory calculations suggest that it results from the hydrogen bonding to the oxo group. We have also demonstrated that the oxidized TDO was activated via a homolytic cleavage of the O-O bond of ferric hydroperoxide intermediate via a substrate dependent process to generate a ferrous TDO. We proposed a peroxide activation mechanism of the oxidized TDO. The TDO has a relatively high redox potential, the protonated state of the proximal histidine upon substrate binding as well as a common feature of the formation of ferric hydroxide species upon substrate or substrate analogues binding. Putting these together, we have proposed a substrate-based activation mechanism of the oxidized TDO. Our work also probed the role of histidine 72 as an acid-base catalyst in the active site. In H72S and H72N mutants, one water molecule plays a similar role as that of His72 in wild type TDO. MauG is a c-type di-heme enzyme which catalyze the biosynthesis of the protein-derived cofactor tryptophan tryptophylquinone. Its natural substrate is a monohydroxylated tryptophan residue present in a 119-kDa precursor protein of methylamine dehydrogenase (MADH). We have trapped a novel bis-Fe(IV) intermediate from MauG, which is remarkably stable. A tryptophanyl radical intermediate of MADH has been trapped after the reaction of the substrate with the bis-Fe(IV) intermediate. Analysis by high-resolution size-exclusion chromatography shows that MauG can tightly bind to the biosynthetic precursor and form a stable complex, but the mature protein substrate does not.
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Majchrzak, Yves. "Evolution des communautés végétales de marais tourbeux soumises au pâturage de bovins et d'équins : application pour la gestion conservatoire d'une zone humide, le marais de Lavours (Ain, France)." Grenoble 1, 1992. http://www.theses.fr/1992GRE10124.
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Pour preserver l'interet ecologique de la reserve naturelle du marais de lavours (ain, france), une gestion pastorale a ete mise en place avec des bovins highland et des chevaux camargue. L'objectif de cette etude a ete de suivre l'impact des herbivores sur les communautes vegetales. Des releves selon la technique des points quadrats alignes ont ete effectues tous les ans a la meme epoque, de 1987 a 1991, sur 102 stations. Ils ont permis de suivre l'evolution de la diversite floristique, du recouvrement des especes vegetales, de la structure de la vegetation et de la dynamique du systeme. Les donnees ont ete traitees grace a l'afc et a l'acp-3 modes (cette derniere technique s'averant tres adaptee dans ce cadre). L'impact des herbivores s'est traduit par: une augmentation du recouvrement de vegetaux rares et de l'heterogeneite structurale; l'augmentation du recouvrement des especes hygrophiles et d'alnus glutinosa, la diminution du recouvrement de sanguisorba officinalis et des especes fourrageres; la diminution de la diversite des facies, de la diversite specifique et du recouvrement de juncus subnodulosus dans le parc des bovins et l'augmentation de la diversite specifique de celui des chevaux. L'evolution des prairies humides vers une fruticee a alnus glutinosa n'est pas stoppee, et il sera necessaire de modifier les modalites de la gestion
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Pooam, Marootpong. "The biological effects of applied magnetic fields on cryptochrome and response." Electronic Thesis or Diss., Sorbonne université, 2020. http://www.theses.fr/2020SORUS062.
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Cryptochromes (cry) sont des flavoprotéines absorbant la lumière bleue conservées qui ont été liées à perception de stimuli électromagnétiques dans de nombreux organismes. Nous avons principalement étudié le mécanisme d'interaction entre les champs magnétiques (MF) et cry dans le cadre de la théorie des paires de radicaux. Nous avons étudié la réponse d'Arabidopsis cry-1 in vivo à MF. Les activités biologiques du cry ont été renforcées par MF. Les effets des MF ont pu être observés même si MF était donné exclusivement pendant les intervalles d'obscurité entre expositions à la lumière. Cette découverte a indiqué que l'étape de réaction magnétiquement sensible dans photocycle du cry doit se produire pendant la réoxydation des flavines. De plus, nous avons également utilisé la fréquence (RF) stimulée par cry-Arabidopsis comme outils de diagnostic pour confirmer l'hypothèse de la paire de radicaux. Dans l'étude, nous avons trouvé un effet perturbateur des RF sur l'activité du cryptochrome. Notre découverte pourrait confirmer l'apparition du mécanisme de la paire de radicaux et l'implication du cry pour la magnétoréception. De plus, nous avons également montré un effet perturbateur de la condition MF statique de bas niveau (LLF) où les champs magnétiques externes étaient presque éliminés. Le résultat de cette condition était cohérent avec l'effet de l'exposition aux RF. En outre, nous avons également signalé que LLF pourrait augmenter l'expression de certains gènes induits par le PEMF dans dans les les cellules humaines. Cette découverte pourrait fournir des preuves à l'appui de l'effet des champs électriques magnétiques et non induits sur la physiologie humaineCryptochromes are highly conserved blue-light-absorbing flavoproteins that have been linked to the perception of electromagnetic stimuli in numerous organisms. We mainly studied the mechanism for the interaction between magnetic fields and cryptochromes in the context of the radical-pair theory. We investigated the response of Arabidopsis cryptochrome-1 in vivo to a static magnetic field. The biological activities of cryptochrome were enhanced by the magnetic field. Interestingly, the effects of the magnetic fields could be observed even the magnetic field was given exclusively during dark intervals between light exposures. This finding indicated that the magnetically sensitive reaction step in the cryptochrome photocycle must occur during flavin reoxidation. Moreover, we also used frequency (RF) stimulated to Arabidopsis cryptochrome as the diagnostic tools to confirm the radical-pair hypothesis. In the study, we found a disruptive effect of RF on the activity of cryptochrome. Our findings could confirm the occurrence of the radical-pair mechanism and the involvement of cryptochrome for magnetoreception. Additionally, we also showed a disruptive effect of the low-level static magnetic field (LLF) condition where the external magnetic fields were almost eliminated. The result of this condition was consistent with the effect of RF exposure. Furthermore, we also reported that LLF could increase the expression of some PEMF-induced genes in human cells. This finding could provide the evidence to support the effect of magnetic, not induced electric fields in human physiology
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AGUZZI, GIULIA. "Lingue straniere e sordità: un percorso possibile." Doctoral thesis, Università Cattolica del Sacro Cuore, 2020. http://hdl.handle.net/10280/78940.
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L’obiettivo di questo lavoro è guidare il docente attraverso la letteratura esistente, gli strumenti già in uso e si propone di fornire una modellizzazione per la pratica didattica delle lingue straniere ad alunni sordi. Nel primo e nel secondo capitolo si raccolgono, analizzano e definiscono le basi teoriche di riferimento per la didattica delle lingue a soggetti sordi. Nello specifico, si definiscono il quadro della glottodidattica speciale, i principi di bisogno speciale e specifico e le linee guida per la didattica in contesti di disabilità, procedendo con l’inclusione della sordità tra le esigenze a cui riferirsi con tali strumenti. Il terzo e il quarto capitolo rappresentano l’applicazione concreta dei modelli esposti con l’applicazione del modello SOMA al mondo della sordità e la costruzione del Profilo Glottomatetico Funzionale dell’alunno sordo. Nell’ultimo capitolo si presenta la proposta operativa di didattica dell’inglese ai sordi, partendo dall’analisi e la scelta dei materiali più accessibili, passando per la progettazione fino ad arrivare alla strutturazione specifica del lavoro di classe.This work aims to guide the foreign language teacher trough the literature on special education needs and deafness, the available tools, and the modeling for everyday practice to encourage the inclusion of deaf students until now considered not teachable. In the first and second chapters, the theoretical approaches to deaf students learning are presented in the contexts of special language teaching, special education, and disabilities. The third and fourth chapters represent the application of those principles to include deaf students in the language classroom activities following the operational models usually used for different learning disabilities. The last chapter offers the concrete model that may guide teachers from their deaf students' needs analysis and the correct material choice for them, passing through the learning project management to get to the specific class lessons, in collaboration with support staff members.
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Koh, Meng hock. "Fission-barriers and energy spectra of odd-mass actinide nuclei in self-consistent mean-field calculations." Thesis, Bordeaux, 2015. http://www.theses.fr/2015BORD0208/document.
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Alors qu’il existe de nombreux calculs microscopiques de barrières de fission pour des noyaux composés pair-pairs, il n’y a cependant que relativement peu de tels calculs pour des noyaux de masse impaire. Ceci est dû aux complications induites par la brisure de la symétric de reversement du sens du temps au niveau du champ moyen qui est engendrée par la présence d’un nucleon non apparié. Pour éviter cette difficulté, des calculs existants pour des noyaux de masse impaire ont tout simplement négligé ces effets de brisure de la symétrie de reversement du sens du temps.Dans ce travail, on se donne pour but d’améliorer la description des barrières de fission, aussi bien que des propriétés spectroscopiques du niveau fondamental et de l’état isomérique de fission,pour quelques isotopes de masse impaire dans la région des actinides en prenant en compte de tels effets. Ceci a été réalisé dans le cadre du formalisme de Skyrme–Hartree–Fock plus BCS avec blocking en adaptant ce formalisme à la brisure de la symétrie considérée. L’interaction résiduelle d’appariement a été approchée par une force de séniorité dont les paramètres ont été ajustés pour reproduire les différences de masse pair-impair de quelques noyaux de la région des actinides.Les énergies des têtes de bande rotationnelle de basse énergie ont été calculées dans le cadre du modèle unifié de Bohr-Mottelson pour quatre noyaux bien déformés (235U, 239Pu, 237Np, 241Am)produisant un bon accord qualitatif avec les données pour les noyaux impairs en neutrons. L’accord significativement moins bon obtenu pour les noyaux impairs en protons pourrait résulter de l’usage de l’approximation de Slater pour l’interaction d’échange de Coulomb. Les énergies de déformation de deux noyaux impairs en neutrons (235U, 239Pu) ont été calculées pour quelques configurations de particule individuelle, jusqu’après la barrières de fission externe. La symétrie axiale a été imposée tandis que la brisure de la symétrie droite-gauche (ou de parité intrinsèque) a été permise dans la région de la seconde barrière. Les hauteurs des barrières de fission pour ces noyaux impairs dépendent significativement des configurations de particule individuelle. Un accord qualitatif avec les données disponibles pour les hauteurs de barrières des noyaux impairs considérés et leurs voisins pair-pairs a été généralement obtenuWhile there have been numerous microscopic calculations on fission barriers of even-even compoundnuclei, there are however, relatively few such work dedicated to odd-mass nuclei. This is dueto the complications posed by the breaking of the time-reversal symmetry at the mean-field leveldue to the presence of an unpaired nucleon. In order to circumvent this difficulty, previous fission barriercalculations of odd-mass nuclei have been performed by neglecting the effect of time-reversalsymmetry breaking. This work aims to improve on the description of fission barriers as well asthe spectroscopic properties of ground and fission-isomeric state, of some odd-mass actinide nucleiby taking the effect of time-reversal symmetry breaking into account. This has been perfomedwithin a Skyrme-Hartree-Fock-plus-BCS framework with blocking, where the BCS formalism hasbeen adapted to accomodate this symmetry breaking. The Skyrme nucleon-nucleon effective forcehas been used with various sets of parameters (SIII, SkM*, SLy5*). The residual pairing interactionhas been approximated by seniority forces whose neutron and proton parameters have beenfitted to reproduce the odd-even mass differences of some actinide nuclei. The low-lying rotationalband-head energies evaluated within the Bohr-Mottelson unified model have been determined forfour well-deformed odd-nuclei (235U, 239Pu, 237Np, 241Am) yielding a good qualitative agreementto the data for odd-neutron nuclei. The agreement was significantly less good for the odd-protonnuclei, possibly due to the use of the Slater approximation for the exchange Coulomb interaction.The deformation energies of two odd-neutron nuclei (235U and 239Pu) have been calculated forsome single-particle configurations up to a point beyond the outer fission-barrier. Axial symmetrynuclear shape has been assumed while a breaking of the left-right (or intrinsic parity) symmetryhas been allowed around the outer fission-barrier. The fission-barrier heights of such odd-neutronnuclei depend significantly on the particle configurations. A special attention has been paid tothe very important rotational correction to deformation energies. In particular, the correction ofthe moment of inertia calculated from the usual Belyaev expression was considered. Overall, aqualitative agreement with available data on fission-barrier heights for the considered odd-neutronnuclei and their even neighbours has been obtained
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Dauby, Gilles. "Structure spatiale de la diversité intra- et interspécifique en Afrique centrale: le cas des forêts gabonaises." Doctoral thesis, Universite Libre de Bruxelles, 2012. http://hdl.handle.net/2013/ULB-DIPOT:oai:dipot.ulb.ac.be:2013/209761.
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L’origine de la structuration spatiale de la diversité inter spécifique (SSDS) des forêts d’Afrique centrale est l'objet de vigoureux débats quant à l’importance relative des facteurs historiques, stochastiques et déterministes. De plus, la SSDS est le plus souvent mal caractérisée, en particulier la variation spatiale de la composition des communautés (diversité beta).L’hypothèse la plus souvent avancée pour expliquer l’origine des centres de diversité et d’endémisme est historique :ces centres constitueraient d’anciens refuges forestiers formés pendant les périodes sèches du Quaternaire. Cependant, la forte hétérogénéité environnementale de ces régions pourrait tout aussi bien expliquer la SSDS.
L'objectif principal de cette thèse est de tester l'importance de ces facteurs (historiques et/ou hétérogénéité environnementale) :si les facteurs historiques sont déterminants, on s’attend à observer une concordance spatiale entre la SSDS et la structure spatiale de la diversité génétique (SSDG). En effet, la variation neutre au sein des espèces est en grande partie soumise aux processus qui affectent également la SSDS (dérive génétique/écologique et dispersion des espèces/flux de gènes). L’approche utilisée dans cette thèse consiste donc à comparer et évaluer la concordance spatiale entre la SSDS et la SSDG.
Le modèle biologique et le cadre géographique de cette étude sont les communautés et les populations d’arbres des forêts humides d’Afrique centrale atlantique, avec une attention particulière pour les forêts gabonaises. La SSDS a été étudiée sur la base de relevés de communautés d’arbres (16308 individus) et la SSDG sur la base de séquences d’ADN chloroplastiques de six espèces d’arbres (Greenwayodendron suaveolens, Scorodophloeus zenkeri, Afrostyrax lepidophyllus, Afrostyrax kamerunensis, Santiria trimera et Erythrophleum suaveolens).
Quatre objectifs spécifiques ont été retenus :
(i)\
Doctorat en Sciences
info:eu-repo/semantics/nonPublished
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Schwoertzig, Eugénie. "Contribution des corridors fluviaux à la dynamique de la biodiversité végétale urbaine." Thesis, Strasbourg, 2016. http://www.theses.fr/2016STRAH005/document.
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L'écologie urbaine, qui a émergé depuis une trentaine d'années, s'intéresse notamment à l'étude de la biodiversité et du fonctionnement des écosystèmes en ville. Ce travail de thèse porte plus particulièrement sur l'analyse de l'écosystème "corridor fluvial", et son rôle dans la dynamique des communautés végétales en fonction d'un gradient d'urbanisation. Les corridors fluviaux assurent en effet une connexion structurelle entre la ville et la campagne, et leur conservation en milieu urbain implique d'en comprendre précisément la fonctionnalité écologique. L'objectif de ce travail est donc de mettre en évidence l'effet du gradient d'urbanisation sur la composition et la structure des communautés végétales le long d'un cour d'eau et de vérifier si l'existence en ville de corridors fluviaux contribue efficacement à la dispersion et à la rapidité de colonisation des milieux adjacents. Deux cours d'eau, la Bruche et l'hydrosystème Rhin Tortu - Ziegelwasser, ont été étudiés dans leur partie aval la plus urbaine au sein de l'Eurométropole de Strasbourg. [...]Urban ecology, which has emerged over the last thirty years, focused in particular on studying thebiodiversity and on functioning of ecosystems in cities. This work explores urban riparian corridors and their rolein the dynamic of plant communities based on a gradient of urbanization. Indeed, riparian corridors provide astructural connection between the city and the countryside, and their conservation involves preciselyunderstanding their ecological functionality. The objectives of this work are to highlight the effect of the urbanization gradient on the composition and structure of plant communities along a river to determine whether the existence of urban riparian corridors effectivelycontributes to the colonization of adjacent areas. Two rivers, the Bruche and the Rhin Tortu - Ziegelwasser, arestudied in their most urban downstream part in the metropolitan area of Strasbourg, eastern France. [...]
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Khamzin, Yersin. "Technologie vstřikování zkušebních těles z termoplastů." Master's thesis, Vysoké učení technické v Brně. Fakulta chemická, 2021. http://www.nusl.cz/ntk/nusl-444217.
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The diploma thesis focuses on the optimization of technological parameters of plastic injection molding and the study of the influence of technological parameters on the quality of molded test specimens’ type 1A. The quality of molded parts for 3 types of polypropylene (PP) with different melt flow rate (Mosten GB 002, Mosten GB 218, Mosten MA 230) and 1 type of polystyrene (PS) (Krasten PS GP 154) was evaluated in terms of dimensional stability and weight. The contribution of software for modeling the plastic injection molding process was evaluated in this work. SOLIDWORKS Plastics software was used to optimize technological parameters. The construction of the bodies, mold and cooling system was constructed, and test bodies were produced on the basis of parameters obtained from the simulation of the injection molding process. Their quality parameters were compared with a 3D model and for each of the studied materials the optimal technological parameters were selected in terms of quality and the degree of influence of individual injection parameters on the quality of moldings was evaluated. The accordance of the results of the theoretical simulation with the real experiment was proved and a computational module independent of the optimized quality parameters, generally suitable for optimizing the quality parameters of the injected parts, was developed.
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Bazin, Cyrille. "L'interface photosphère solaire/chromosphère et couronne : apport des éclipses et des images EUV." Phd thesis, Aix-Marseille Université, 2013. http://tel.archives-ouvertes.fr/tel-00921889.
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Les régions d'interface du Soleil de la photosphère à la chromosphère et au delà de la basse couronne ont été étudiées depuis longtemps à partir des spectres éclairs obtenus durant les éclipses totales de Soleil. Les éclipses sont les plus adaptées à ce type d'observation, car l'occultation a lieu en dehors de l'atmosphère terrestre et sont exemptes de lumière parasite provenant du " disque occulteur " (c'est-à-dire la Lune), une propriété de grande importance lorsqu'on observe très près du limbe. La résolution temporelle des premiers spectres éclairs ne permettait pas de résoudre les basses couches de la région de transition et étaient dégradés par des effets non-linéaires qui affectaient les films photographiques. Les images Extrême-UV des régions du limbe obtenues récemment dans l'espace sont analysées avec des modèles hydrostatiques à une dimension, comme les modèles VAL, mais cette méthode ne tient pas compte du phénomène d'émergence du champ magnétique, associé au réseau chromosphérique qui est responsable de: i) les spicules et le milieu interspiculaire, ii) les jets coronaux et macrospicules, et iii) l'ovalisation de la chromosphère. Les composants de la région d'interface sont dynamiques et différents types d'ondes et de reconnexions magnétiques sont supposées agir. Un saut de température de 0.01 à 1 MK est observé autour de 2 Mm d'altitude plus loin, et produit plus loin le flot du vent solaire permanent. Le processus de chauffage responsable du saut de température et la source du vent solaire ne sont pas encore compris. Dans cette thèse, nous traitons ces problèmes à partir de spectres éclairs récents réalisés avec les technologies actuelles de détecteurs CCD rapides, images d'éclipse en lumière blanche et des images EUV obtenues avec des instruments de missions spatiales. Nous illustrons les mécanismes des émissions des raies à faible potentiel de première ionisation (FIP) présents dans les basses couches de l'atmosphère solaire. Nous identifions plus précisément les raies associées aux éléments low FIP à la fois à l'intérieur et en dehors des protubérances. Nous caractérisons en détail les enveloppes d'hélium dans les interfaces. Méthodes: 1) technique des spectres éclairs sans fente avec imagerie CCD rapide (éclipses 2006, 2008, 2009, 2010 et 2012). 2) Analyses des spectres du continu entre la myriade de raies d'émission au delà du limbe solaire et construction de courbes de lumière de quelques raies d'émission low FIP et high FIP. 3) Evaluations d'inversions d'intégrales d'Abel pour déduire des échelles de hauteurs et discussion de variations de température et de densité. 4) Analyse d'images EUV obtenues aux mêmes instants depuis AIA/SDO, SWAP, SOT/Hinode des missions spatiales, images en lumière blanche pour discuter des constituants de la couronne. Principaux résultats: i) Le bord du Soleil et la bifurcation de température : le vrai continu à partir du spectre observé aux altitudes de 400 à 600 km au dessus du limbe dans le contexte de de mesures de diamètre solaire et processus d'émission. ii) raies d'émission visibles dans les régions d'interface comprenant les raies He I et surtout la raie He II Pα visible à partir de 800 km au dessus du limbe, produite par photo-ionisation, montrant des enveloppes autour du Soleil et permettant le sondage de l'interface protubérance-couronne. iii) La contribution de structures de petite taille comme les spicules et macrospicules commençant à 1 Mm au dessus du limbe et montrant que les modèles hydrostatiques stratifiés 1D ne sont pas adaptés pour les couches supérieures. Nous montrons que les raies low FIP sont sur-abondantes dans l'interface photosphère-chromosphère, que la couronne solaire est alimentée en permanence par ces éléments. Le titane est un élément abondant dans le milieu interspiculaire, et une analogie sur les gradients de température entre les interfaces photosphère-chromosphère et protubérance-couronne peut être établie.
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Bodin, Jeanne. "Observed changes in mountain vegetation of the Alps during the XXth century - Role of climate and land-use changes." Phd thesis, Université Henri Poincaré - Nancy I, 2010. http://tel.archives-ouvertes.fr/tel-00592144.
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La végétation herbacée est un bon indicateur des conditions environnementales. Pour cette raison, elle a souvent été utilisée pour mettre en évidence les changements environnementaux causés par les actions humaines, tels qu'eutrophisation, dépôts atmosphériques acides, changements de l'usage des sols ou de la pression d'herbivorie. Depuis peu, on s'intéresse aux effets des changements climatiques sur les écosystèmes en général, et sur la végétation en particulier. Le choix des zones d'étude s'est naturellement porté sur la montagne, car le gradient thermique induit par le relief (-0,56°C pour 100 mètres d'altitude) y est mille fois plus élevé qu'en plaine le long du gradient latitudinal. D'autre part, les zones de montagne sont soumises à une urbanisation et une pression agricole moindre qu'en plaine, limitant ainsi les obstacles à la migration des espèces. Ces deux arguments font des régions de montagne une zone privilégiée pour l'étude de la réponse migratoire précoce de la végétation aux changements climatiques. Jusqu'ici, les études effectuées se sont focalisées pour la plupart sur la limite supérieure des espèces, ou sur de petites zones géographiques, ou bien encore sur des zones où il est difficile de dissocier les effets du réchauffement de ceux des changements d'usage des sols, qui se produisent eux aussi à grande échelle. Une partie de cette thèse est consacrée aux milieux forestiers montagnards, dans lesquels l'effet du pastoralisme est réduit. D'autre part, une méthode basée sur la modélisation des changements de la réponse de la végétation au gradient d'altitude est développée, permettant le rééchantillonnage sur placettes non-permanentes, et ainsi d'étendre l'utilisation de données anciennes à des séries de relevés non géolocalisés. En s'appuyant sur cette méthode, deux caractéristiques de la végétation ont été analysées : la position de l'optimum d'espèces prises individuellement d'une part (données de l'Inventaire Forestier National dans les montagnes méditerranéennes du sud-est de la France), et les changements de la valeur indicatrice des communautés végétales d'autre part (vallée de la Maurienne, France). Par ailleurs, on a étudié les déplacements à long terme de la limite inférieure des espèces dans la vallée de la Bernina (Suisse), pour tester si la réponse des espèces en limite inférieure, peu étudiée jusque là, est identique à celle en limite supérieure de leur distribution. Enfin, on a étudié l'évolution de la flore d'une zone très localisée, mais par ailleurs protégée des migrations d'espèces par une large barrière physique constituée par deux glaciers (Nunatak Isla Persa, Bernina, Suisse) permettant de s'affranchir totalement des effets potentiels d'autres perturbations anthropiques concomitantes. Dans ces différentes études, les intervalles de temps entre chaque inventaire ou échantillonnage varient de 14 ans à un siècle. Chacun des cas étudiés montre une remontée des espèces en altitude : remontée moyenne de +12,6 m/décennie des optimums de 175 espèces forestières dans les montagnes méditerranéennes, communautés des forêts de Maurienne évoluant vers une végétation plus thermophile à une altitude donnée équivalent à une remontée moyenne de +29.6m/décennie, retrait de la limite inférieure des espèces en Bernina de +5,6 m/décennie, arrivée d'espèce d'étages inférieurs sur le nunatak Isla Persa. Mais d'autres phénomènes expliquant la réponse observée de la végétation sont clairement mis en cause dans cette étude : fermeture et maturation du couvert forestier relativement plus importante à basse altitude dans les montagnes méditerranéennes, eutrophisation importante de la végétation en vallée de la Maurienne probablement due à l'augmentation du trafic routier, probable fragmentation de l'habitat ou dispersion par les randonneurs en Bernina. Ces perturbations anthropiques directes jouent à des échelles de temps et d'espace comparables à l'effet anthropique indirect du changement climatique. Il est donc primordial de les prendre en compte dans les changements de végétation observés, avant de conclure à un effet du réchauffement climatique seul.
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Senterre, Bruno. "Recherches méthodologiques pour la typologie de la végétation et la phytogéographie des forêts denses d'Afrique tropicale." Doctoral thesis, Universite Libre de Bruxelles, 2005. http://hdl.handle.net/2013/ULB-DIPOT:oai:dipot.ulb.ac.be:2013/210954.
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I. An original methodological discussion is proposed on the problem of the typology of tropical rain forest’s plant communities, based on the study of forest types across gradients of continentality and elevation, within Atlantic central Africa. These investigations were based on the statement that the main problems in forest typology are related to the non-zonal or zonal character of the different vegetation types and to non considering the relations and differences between forest strata.II. Field data consisted in phytosociological homogeneous sample plots localized within different recognized phytogeographical entities, in a region of tropical Africa where these entities are known to be well conserved. A total of 37 such plots were inventoried in the region extending from the littoral forests of Ndoté, Equatorial Guinea, which are wet evergreen forests, to the continental forests of the Dja, Cameroon, known as evergreen seasonal forests. The studied region also included the oriental Atlantic forests of Equatorial Guinea, known as moist evergreen forests or caesalp forests. In various parts of this continentality gradient, some plots were localized within climax non-zonal formations, namely the submontane rain forests. The emphasis was put on the vegetation of the Monte Alén National Park.
The sampling methodology was willing to be as "complete ", including all strata, "quantitative ", enumerating all individuals, and "representative ", within each stratum, as possible. These multi-layers plots were realised using nested sub-plots, with a sampling size of 100 individuals for every ligneous stratum recognized (dominant trees, dominated trees and shrubs) and a sampling size of 200m² for the herbaceous and suffrutex stratum.
Forest types were defined independently for each stratum and the differences were analysed. A method was proposed for the simultaneous analysis of all floristic data, converting and standardizing the values from ligneous strata, on the one hand, and from understorey strata, on the other hand.
III. Ten forest types were described using IndVal and discussed in the general context of the guineo-congolian region, from a syntaxonomic view point (agglomerative classification) and from a phytogeographical view point (divisive classification). Homologies between these two approaches are described. The proposed phytogeographical system is based on an "open " conception of hierarchical classifications, combining advantages of agglomerative and divisive classifications. In concrete terms, the non-zonal criteria, for example the submontane variants, are categorised separately and in analogy with the zonal criteria, related to the usual phytochoria.
Analysis of ecological relationships for the 10 communities showed that the main variables related to the floristic variability in our mainland rain forests are elevation, rainfall, hygrometry (estimated using bryophytes cover levels) and distance to the ocean. The two extremes on the vertical microclimatic gradient, dominant trees stratum and herbaceous stratum, give similar typologies, however canonical analysis showed that for the herbaceous layer, non-zonal variables (hygrometry and elevation) were gaining more importance when the influence of the two zonal variables was attenuated. In every case, spatial autocorrelation was less important than the environment in explaining floristic variability but its role increased in the spatial arrangement of understorey species, whose dispersal capacity is generally lower than canopy trees. The phytosociological, phytogeographical and ecological description of forest types is accompanied by a physiognomical description using biological types spectrum, as well as architectural models, leaf sizes, etc.
With regard to diversity, we have demonstrated that species richness was higher from upper to lower strata because of the accumulation in lower strata of species from various strata. On the other hand, the proper stratum diversity, i.e. the structural set, decreased from dominant trees to shrubs. The proper diversity of the herb layer showed relatively high figures mainly due to the higher individual density in relation to the existence of microstrata. Within the 37 sample plots, 1,050 taxa have been identified to species or morpho-species levels, for a total of 25,750 individuals. These taxa represent 442 genus among 104 families. The richest forest type is found on the foothills of the Niefang range, on the windward side. This forest type is also characterised by a high number of oligotypic genus and by species belonging to functional types indicators of glacial refuges. These functional types are defined on the basis of the dispersal capacity and on kind of stand needed for effective germination. We formulated the hypothesis that this kind of "foothills refuge ", characterised by his zonal nature, could have been one of the rare refuges for species from mainland rain forests, while montane and fluvial refuges would mainly have preserved species from non-zonal forest types: (sub)montane and riverine.
Based on indicator species of submontane forests, a potential distribution map of this forest type has been realised at the Atlantic central African scale. More than 400 submontane forest localities have been mapped. These forests begin at 400m of altitude near the ocean, and progressively at higher altitude for increasing distance to the ocean. Many lowland localities also comprised submontane species, which could indicate the existence of ecological transgressions. These transgressions would allow migratory tracks for submontane species between isolated mountain ranges, not only during glacial periods, through heights at the northern and southern borders of the congo basin, but also contemporarily through the lowland riverine forest network, in the centre of this basin. Finally, a special attention has been attributed to littoral forests and to some cases of choroecological transgressions, coupled to the ecological equalization phenomenon.
Doctorat en sciences agronomiques et ingénierie biologique
info:eu-repo/semantics/nonPublished
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Sandler, Hilary A. "Factors influencing colonization and establishment of plant species on cranberry bogs." 2004. https://scholarworks.umass.edu/dissertations/AAI3118331.
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The objective of this study was to obtain and interpret field data related to the establishment of cranberry (Vaccinium macrocarpon Ait.) plantings, as well as examine the impact of conventional weed management practices on yield components and weed control. Integrated weed management, recently recognized by weed scientists as a desired goal for research and extension, is an important part of current cranberry production. This research was designed to permit the incorporation of the collected data into practical grower recommendations, as well as to expand our general knowledge about invasion ecology and plant species composition in new and established commercial plantings. Data from four years of repeat annual applications of 0, 1.8, and 4.5 kg ai/ha dichlobenil in low-weed and high-weed density areas indicated minimal negative impact on cranberry vines. Herbicide application did not adversely affect upright productivity, biomass, fruit set, or other yield parameters; in addition, no improvements for these parameters were noted. No consistent treatment effect on cranberry root length was seen. The presence of weeds, rather than herbicide application, was the important determinant of yield. Vines in low-weed density areas produced more marketable fruit and had higher percentage fruit set than vines growing in high-weed density areas. Results suggest that repeat annual applications of dichlobenil to commercial cranberry beds may be considered as part of a viable integrated weed management program with no adverse effect on crop growth or yield. One specific goal of this research was to identify the most beneficial combination of nitrogen rate, vine planting density, and weed management option that would promote quick and economical vine establishment of the cultivar, Stevens, while providing adequate and cost-effective weed control. After two years, several treatment combinations seemed promising for commercial implementation. However, the most cost-effective production scheme for establishing a new planting was to plant vines at a low density, use moderate rates of nitrogen, and apply a yearly application of napropamide for weed control. This combination produced substantial vine coverage at very low cost, reduced weed biomass by 85% compared to the untreated plots, and gave the best control per dollar spent.
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Jiang, Jhih-hua, and 江志華. "The effect of accelerated carbonation on the calcium species transformation of BOF slag." Thesis, 2010. http://ndltd.ncl.edu.tw/handle/4ng5hv.
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碩士國立臺北科技大學
資源工程研究所
98
In this study, the effects of accelerated carbonation on the chemical properties, mineral morphologies and microstructures of BOF slag under various accelerated carbonation parameters are evaluated. Under optimum accelerated carbonation parameters, the results indicate that particle size 3.5 to 7mm, 7 to 15mm and 15 to 25mm of BOF slags individually lowered their pH values from 12.3, 12.0 and 11.9 to 10.8, 10.5 and 10.4. Besides, thermal weight loss of BOF slags for particle size 3.5 to 7mm, 7 to 15mm and 15 to 25mm individually increased from 1.28 %, 1.09 % and 0.79 % to 1.72%, 1.38% and 1.57%. The mineral morpgology micrographs and SEM micrographs of accelerated carbonation BOF slags show that the surface of BOF slag was feasible to form calcium carbonate. The XRD patterns of accelerated carbonation BOF slags show that there were calcite on the surface of BOF slag and the spectra of FTIR of accelerated carbonation BOF slags indicate that there were CO32- function groups presenting on surface of carbonated accelerated carbonation BOF slags. Based on the investigation of chemical properties, mineral morphologies and microstructures of accelerated carbonation BOF slags on different reaction time, the results show that the grain size and thickness of calcium carbonate and the diffraction peak intensity of calcite on accelerated carbonation BOF slag surface increase with the reaction time. The calcium carbonate of BOF slag surface was formed by the reaction of Ca(OH)2 and CHS gels produced from the hydration of the f-CaO and Ca2SiO4 with carbon dioxide through aqueous carbonation. Furthermore, the results in accordance with TCLP and Tank Leaching tests indicate that the leaching concentration of Cu, Cr, Pb,Ni and Zn in accelerated carbonation BOF slag was obviously decreased. Based on the above results, accelerated carbonation of BOF slag not only reduces high alkalinity of BOF slag and leachability of heavy metals in BOF slag, but also promotes the utilization of BOF slag and reaches the reduction of carbon dioxide.
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Lee, Min-Ling, and 李敏菱. "A Study on Treatment of Wastewater Containing Copper Species by Using Powdered BOF Slag." Thesis, 2011. http://ndltd.ncl.edu.tw/handle/es2m2z.
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碩士國立臺北科技大學
資源工程研究所
99
The purpose of this study was to investigate the effectiveness of using powdered BOF slag to remove the copper-ion contaminants in wastewater. The BOF power, obtained from the burnt ashes, was purified and analyzed to have particle sizes of >900 μm, 150-900 μm, <150 μm and different L/S ratio for treating time period of 5, 10, 30 and 60 min. The set of experiments were designed to demonstrate the purpose of waste water treatment by utilizing the inexpensive BOF slag powder. Powdered BOF slag is heterogeneous oxide materials and analyzed to have the compositions of Fe2O3 46.0-51.6% and CaO 35.3-45.0%. The BOF powder with different particle sizes on L/S ratio 1000 and 30 min were tested for removal of Cu(Ⅱ) and Cu-EDTA solution. The results indicated that the smaller size of the powdered BOF slag the better for the copper ion removal. When the <150 μm size slag was used under the conditions of 30 min and L/S ratio 1000, nearly 100% of the total Cu(Ⅱ) in water solution was removed. The tests of different L/S ratio (200, 500, 1000 and 2000) at the treatment time of 5, 10, 30 and 60 min showed that the increase in L/S ratio and time period were generally the better results. For other tests of that <150 μm powdered BOF slag in L/S ratio 2000, it was determined to be 100% and 90% of Cu(Ⅱ) and Cu-EDTA solution, respectively. There results will be useful for future scale-up runs for further studies on the powdered BOF slag removal of the waste water containing copper ions. The experiments also showed that the powdered BOF slag had the main constituent CaO and other alkaline metals. Further investigation regarding of the released calcium and copper removal for powdered BOF slag was performed. It was found that the calcium component is responsible for the removal of copper ions. In the Cu-EDTA solution, the TOC concentration decreases if the treatment time increases. Both of Freundlich and Langmuir Isotherm Equations were followed and found that the data could be successfully described by the Freundlich Isotherm Equations. The recovered BOF slag powder from the treatment with copper ions was examined by using X-ray Diffraction (XRD) and Scanning Electronic Microscopy (SEM). The XRD pattern remained the same but the surface smoothness had increased in the case of Cu-EDTA solution treatment. By comparison, the Cu(Ⅱ) solution did not affect the powder particle surface. Furthermore, the solution after treatment was analyzed for the metal concentration to detect the possibility of metal leaching from the BOF slag powder. According to the TCLP test, the leaching concentration of Pb (Ⅱ), Cr(Ⅱ), Cr(Ⅱ), Cu(Ⅱ), Ba(Ⅱ), As(Ⅱ), Se(Ⅱ) and Hg(Ⅱ) was minimum. Overall, the evaluation of using the BOF slag power has proven to be useful and low-cost material for removing Cu(Ⅱ) ions from waste water.
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Catarina, Almeida Ana. "DNA damage in two bivalve species: Mytilus galloprovincialis and Ruditapes decussatus from the South coast of Portugal." Master's thesis, 2009. http://hdl.handle.net/10400.1/447.
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Dissertação de mest., Estudos Marinhos e Costeiros, Faculdade de Ciências e Tecnologia, Universidade do Algarve, 2009In the last years, several studies have been carried out to assess the environmental “health” of the South Coast of Portugal. The aim of the present thesis was to evaluate DNA damage as a biomarker of genotoxic contamination in two bivalve species from the south coast of Portugal, mussels Mytilus galloprovincialis and clams Ruditapes decussatus. Mussels were sampled at nine sites along the coast, and clams were collected at four shellfish beds in the Ria Formosa Lagoon. The alkaline version of the Comet assay was used to estimate the DNA damage present in the haemolymph of bivalves. An image analysis system (Komet 5.5, Kinetic Imaging Ltd) was applied and 3 parameters were calculated, Tail DNA (%), Olive Tail Moment (OTM; arbitrary units) and Tail length (μm). Data obtained for both species were low, in the same order of magnitude for sites considered as reference. These values can be used as baseline/reference levels of the genotoxic contamination for future studies made in the South coast of Portugal. The nature and magnitude of contaminants in this coast were not particularly genotoxic. DNA damage present in mussel and clams haemolymph revealed to be a sensitive biomarker of genotoxic contamination. DNA damage in both specimens responded to the existing differences between sites and seasons, with highest values during summer. This damage biomarker was also sensitive to gender differences concerning both species and the overall data indicates that females have higher DNA damage than males. Moreover, this study demonstrated that information about the condition index (and Abstract - iii - reproductive cycle) and the local abiotic conditions are essential for the appropriate explanation of data. When comparing the DNA damage between the two analysed species, collected from close sites, DNA damage was relatively similar for both bivalve species. However, while mussels had highest DNA damage in August, clams showed maximum values in February/March, suggesting some interspecific differences possibly associated with dissimilar trophic strategies and/or habitats. Lipid peroxidation (LPO) was also analysed, to verify if the environmental conditions (contaminants and abiotic factors) can induce injuries in both cellular membranes and DNA. For mussels, the compounds/factors affecting LPO can also promote (low) genotoxicity. For clams, this relationship was only verified during July. Concluding, the present thesis demonstrates that the DNA damage present in M. galloprovincialis and R. decussatus is a sensitive biomarker to discriminate spatial, temporal and genders differences, revealing to be an appropriate tool for the evaluation of genotoxic contamination along the South coast of Portugal.