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Environmentally-determined tissue temperature modulates extremity growth in mammals: A potential comprehensive explanation of Allen's ruleSerrat, Maria A. 27 July 2007 (has links)
No description available.
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Planering av förbifarter och ringleder i tätorter : En dokumentstudie om vägplanering / Planning of bypasses and ring roads in localities : A study about road planningKauppi, Jonathan January 2024 (has links)
We are constantly building new roads and are trying to make them safer and more efficient. This thesis has looked into how the benefits and disadvantages has been described with building new roads and specifically bypass roads. The thesis has also explored on how the handling of the citizens have been made from the municipal part and from the side of the Swedish Transport Administration. The analysis in this study has been made with a directed content analysis, this means that the previous scientific research and theories have been used to form the framework used in the coding scheme. Documents from the municipalities and planning documents from the Swedish Transport Administration have been used in the coding scheme. In total 10 documents combined have been analyzed from Skellefteå, Söderköping and Linghem connected to the building of bypass roads in the localities. The study has shown that in all the localities there are negative effects on the environment, landscape and land that is being used, but in all the cases the Swedish Transport Administration and the municipalities argue that the roads have more positive benefits than negative, the bypass roads lead to a higher traffic safety, less emissions and a better accessibility in the central parts of the localities. Regarding the communications it’s clear that the municipalities prioritize the inhabitants and are constantly working to improve it. The Swedish Transport Administration works with communication in all the stages in the planning process. Both the municipalities and the Swedish Transport Administration describe that they value the public interest higher than the private. But with how the Swedish Transport Administration works with communicative planning it could be concluded that they only follow the necessary steps that they are legally required to.
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Simulation of Fatigue Performance & Creep Rupture of Glass-Reinforced Polymeric Composites for Infrastructure ApplicationsMcBagonluri-Nuuri, David Fred 21 August 1998 (has links)
A simulation model which incorporates the statistical- and numerical-based Lattice Green Function Local Load Sharing Model and a Fracture Mechanics-based Residual Strength Model has been developed. The model simulates creep rupture by imposing a fixed load of constant stress on the composite over the simulation duration. Simulation of the fatigue of glass fiber-reinforced composites is achieved by replacing the constant stress parameter in the model with a sinusoidal wave function. Results from the creep rupture model using fused silica fiber parameters, compare well with S-2 glass/epoxy systems. Results using Mandell's postulate that fatigue failure in glass fiber-reinforced polymeric composites is a fiber-dominated mechanism, with a characteristic slope of 10 %UTS/decade are consistent with available experimental data. The slopes of fatigue curves for simulated composites for three frequencies namely: 2, 5 and 10 Hz are within 12-14 %UTS/decade compared with that of 10.6-13.0%UTS/decade for unidirectionl glass reinforced composites (epoxy and vinyl ester) obtained from Demers' [40] data. / Master of Science
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Stratégies de reproduction des femelles du kangourou géant (Macropus giganteus)Gélin, Uriel January 2014 (has links)
Résumé : La reproduction entraîne des dépenses énergétiques importantes chez les femelles mammifères. Ces dépenses sont supposées diminuer l'énergie disponible pour d'autres traits positivement corrélés à l'aptitude phénotypique et augmenter les besoins d'alimentation. Toutefois, des différences individuelles dans la capacité d'acquisition et d'allocation peuvent masquer l'impact négatif de l'effort reproducteur. La manipulation expérimentale de l'effort reproducteur et le contrôle statistique des effets individuels sont deux approches puissantes et complémentaires mises en œuvre dans le cadre de mon étude afin de contrôler pour l'hétérogénéité individuelle. Elles ont permis de montrer clairement un coût de la reproduction chez le kangourou gris de l'Est (Macropus giganteus). Dans un premier temps, nous avons trouvé que le coût de la reproduction affectait le montant d'énergie alloué à certaines fonctions somatiques (CHAPITRE I). L'effort reproducteur diminuait le gain de masse et la croissance des jambes pour des intervalles de capture supérieurs à deux ans. Chez les femelles non manipulées, un effet négatif sur le gain de masse était aussi observable pour un intervalle inférieur à 3 ans. À l'échelle de deux événements successifs de reproduction, le gain de masse et dans une moindre mesure la croissance des bras, mais non des jambes diminuaient avec un effort reproducteur plus important à la précédente reproduction. Ensuite, nous avons démontré qu'il y avait un coût de la reproduction en terme de futur succès reproducteur (CHAPITRE II). Les individus dont l'effort reproducteur avait été diminué expérimentalement produisaient davantage de jeunes qui survivaient au stade 'LPY', âgés approximativement de 7 mois, que les femelles contrôles. Ils diminuaient également davantage leur taux de reproduction en allongeant l'intervalle entre les naissances, mais la survie au sevrage n'était pas affectée. Le CHAPITRE III montre que les femelles adaptaient leur comportement alimentaire en fonction de leur statut reproducteur. En comparaison avec les individus manipulés ou ayant perdu leur jeune, les femelles allaitantes augmentaient leur temps passé à s'alimenter durant la journée, l'intensité de leurs bouchées et de leur mastication sans impliquer de compromis avec la vigilance. Nous avons aussi découvert que la survie au sevrage du jeune précédent menait à une augmentation du taux de bouchées pour l'année en cours.
Les CHAPITRES I et II ont mis en évidence l'effet non négligeable des différences individuelles sur la détection des coûts de la reproduction. En effet, en l'absence de manipulation expérimentale ou de contrôle statistique, aucun compromis n'était détecté autant en terme de croissance que de prochaine reproduction. Au contraire, des corrélations positives entre l'effort reproducteur et les autres traits ont été trouvées. Le CHAPITRE I suggérait notamment que cette variabilité du succès reproducteur était liée à l'hétérogénéité individuelle dans le gain de masse maternelle qui augmentait la survie du jeune. Dans le CHAPITRE II, une corrélation positive entre les probabilités d'avoir un 'LPY' lors de deux événements successifs de reproduction suggérait que certaines femelles étaient capables de mener à bien ou non leur reproduction, mais cela indépendamment de l'effort reproducteur précédent. Enfin dans le dernier CHAPITRE (III), l'effet aléatoire était significatif dans l'analyse de différents comportements d'alimentation, ce qui pourrait être lié aux différences de gain de masse des femelles présentées dans le CHAPITRE I.
Certaines contraintes individuelles affectant le coût de la reproduction ont été identifiées. La masse et la condition corporelle augmentaient le succès reproducteur et diminuaient l'intervalle entre deux naissances successives (CHAPITRES I et II), mais contrairement à de précédentes études le comportement d'alimentation des femelles n'était pas affecté par leur masse (CHAPITRE III). L'âge des individus avait également une influence. Les jeunes femelles croissaient davantage, avaient aussi une prise alimentaire plus importante et subissaient un coût de reproduction supérieur. Ce dernier se traduisait par un taux d'échec plus élevé à la reproduction suivante si les jeunes femelles avaient eu un jeune l'année précédente (CHAPITRES I, II et III).
Des contraintes environnementales fortes influençaient la reproduction des femelles. La croissance, le succès reproducteur, l'intervalle entre les naissances et les comportements d'alimentation variaient suivant le site et l'année d'étude. Le site du Promontory et l'année 2011 apparaissaient particulièrement limitants. En effet en 2011, le gain de masse et le succès reproducteur ont diminué et l'intervalle de naissance et la prise de nourriture pour les femelles allaitantes ont augmenté (CHAPITRE I,II et III).
Nous cherchions également à mettre au jour une allocation différentielle des mères suivant le sexe de leur jeune. Si le coût supérieur d'avoir un mâle par rapport à une femelle était évident quant aux taux de bouchées (CHAPITRE III), il s'est avéré plus difficile à détecter sur d'autres traits. À Anglesea, les jeunes mères avaient moins de probabilité d'avoir un jeune qui atteigne le stade 'LPY' après avoir eu un fils qu'une fille (CHAPITRE II). Toutefois, des résultats contraires à nos attentes ont été trouvés, du moins au premier abord, sur la croissance et le succès reproducteur subséquent. Ainsi, les femelles qui avaient eu une fille perdaient davantage de masse (CHAPITRE I) et avaient généralement une probabilité moindre de produire un jeune qui atteigne le stade 'LPY' ou qui soit sevré par la suite (CHAPITRE II). En revanche, l'intervalle de naissance n'était pas différent suivant le sexe du jeune alors qu'il était fortement affecté par le coût de la reproduction démontré grâce à la manipulation, invoquant une autre explication qu'un coût supérieur des filles par rapport aux fils. En effet, les femelles qui étaient en mauvaise condition corporelle gagnaient de la masse quand elles produisaient une fille, mais pas un fils (CHAPITRE I). De surcroît, les jeunes mères avaient moins de chances de sevrer un jeune à l'événement de reproduction suivant si elles avaient eu un fils plutôt qu'une fille, et le succès reproducteur des mères des fils n'était plus différent de celui des mères des filles dans les années plus difficiles (CHAPITRE II). Enfin, les mères des fils augmentaient la quantité de nourriture ingérée si elles avaient sevré un jeune l'année précédente, mais les mères des filles la diminuaient. Ces différents résultats suggéraient fortement qu'un ajustement du sexe-ratio était utilisé quand les ressources individuelles ou environnementales contraignaient davantage la reproduction.
En conclusion, pour limiter le décalage entre les besoins énergétiques et la disponibilité en nourriture, les femelles chez le kangourou gris de l'Est pourraient modifier l'allocation de leurs ressources à la reproduction en reportant la prochaine mise bas et en produisant un jeune du sexe le moins coûteux en accord avec les contraintes individuelles et environnementales. Ces résultats soulignent l'importance d'études avec un suivi individuel sur plusieurs années afin de pouvoir comprendre la variabilité des stratégies de reproduction et leurs conséquences sur la dynamique des populations. // Abstract : Reproduction in living beings, particularly in female mammals that produce milk, is costly, potentially involving trade-offs with life-history traits if resources are limited and an increase in foraging effort. Individual differences may, however, hide the negative effects of this cost on life-history traits. I used two powerful and complementary approaches, to deal with individual heterogeneity: experimental manipulation of reproductive effort and statistical control of individual effect. Using both approaches, I investigated the effect of presence, size and sex of young on growth, subsequent reproduction and individual foraging behaviours of females. I used data of tagged free-ranging eastern grey kangaroos (Macropus giganteus) collected over six years at five study sites in Victoria, Australia. There was a clear cost of reproduction. Reproductive effort decreased mass gain and limb growth for inter-capture intervals greater than two years. Over two successive reproductive events, mass gain and arm growth were reduced but leg growth was independent of reproductive effort (CHAPTER II).In addition, survival to Large Pouch Young ('LPY') stage, about 7 months of age, was higher and birth rate lower in manipulated compared to control females but survival to weaning was not affected (CHAPTER III). CHAPTER IV shows that lactating females cope with current reproductive costs by increasing ivtime spent foraging as well as bite and chewing rates without decreasing vigilance comparedto non lactating ones. Bite rate was also greater for females that weaned a young at the previous reproductive event. My study supports reproductive cost hypothesis while showing substantial individual differences. To limit mismatch between energetic needs and resource availability, females of eastern grey kangaroo could modify resource allocation to reproduction by delaying birth date of subsequent young and producing the less costly sex according to individual and environmental constrains. My thesis shows the importance of experimental approach and individual monitoring over multiple years to understand the diversity of reproductive strategies and their consequences in evolutionary ecology and population dynamic.
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Evaluating the toxic effects of industrial waste from a historic landfarming site using bioassaysVan Wyk, Mia 12 1900 (has links)
Thesis (MSc)--University of Stellenbosch, 2011. / ENGLISH ABSTRACT: Landfarming is a widely used method for the disposal of contaminants in the petrochemical industry. It involves ploughing the contaminants into the top soil layer allowing biological breakdown. A historically landfarmed site was identified at a South African petrol refinery. The refinery used to dispose so-called American Petroleum Institute (API) -sludge onto a landfarming site. API-sludge consisted of a mixture of oil and water soluble contaminants originating from a process of separating refinery waste from reusable water and oil. Landfarming on this site was discontinued after excessive quantities of sludge were ploughed into the soil over time and it became obvious that effective biodegradation could not take place. An environmental assessment had to be carried out to assess to what extent the soil has recovered from the contamination and after remediation was done over time.
Bioassays together with chemical analyses were executed to determine the level of pollutants in the soil and to assess the integrated effects of their bioavailable fractions.
The landfarming site of the refinery was divided into two sections namely, a more contaminated north-site and less contaminated south-site. Soil samples were collected from both sites as well as from an off-site (control site). The soils were analysed physically, chemically and used in the bioassays. Two additional control soils were also used, OECD-soil and LUFA2.2 soil.
Chemical analysis of the site soils showed the presence of heavy metals and high levels of diesel range organic hydrocarbons. The north-site had higher levels of contaminants compared to the south-site.
Three species of soil organisms were used in standardised tests: Eisenia andrei, Enchytraeus doerjesi and Folsomia candida were exposed to the respective soils to study their survival, growth, reproduction success and avoidance behavior. Exposures to both site-soils were not acutely toxic to any organisms. F. candida had a decrease in juvenile production in both north- and south-site soils (289.42 ± 58.62 and 253.33 ± 122.94 respectively) compared to the control soil (479.89 ± 30.42). E. doerjesi showed an increase in produced juveniles exposed to north- and south-site soil (339.75 ± 76.92 and 414.00 ± 17.78 ) compared to control soil (57 ± 34.39). E. andrei had similar cocoon production when exposed to south-site soil than in off-site soil (19.00 ± 5.3 and 18.5 ± 9.7 respectively) but significantly less in north-site soil (1.25 ± 0.7). Only E. doerjesi showed avoidance of north-site soil.
To determine the sensitivity of the organisms to the API-sludge, they were exposed to concentration series of API-sludge-spiked control soils. The effect concentrations were calculated as the concentration of API-sludge that will decrease the studied endpoints by 50% of the control soil (EC50). The EC50s varied for each species exposed in the different control soils showing that the toxicity of the API-sludge is to a certain extent dependent on the physical soil properties of the substrate. The reproduction of F. candida were most sensitive to the API-sludge in off-site soil (EC50 = 90 mg/kg) and the E. doerjesi the least sensitive in LUFA2.2 soil (EC50 = 36000 mg/kg).
Five plant species were exposed to API-sludge-spiked potting soil and the germination success, early growth rate and biomass were studied. The plants were not as sensitive to API-sludge as the soil animals. Lettuce and grass were affected the most by API-sludge and beans were the most resilient species. With the addition of low levels API-sludge to the substrate, the growth rate of beans was stimulated.
This study showed that the south-site has been successfully remediated and most soil organisms exposed to these soils were not affected by the levels of toxicants present. However, exposures to north-site soil still had negative effects on soil organisms. It is recommended that hydrocarbon contamination should be further remediated in the north-site soil before landfarming should be allowed to continue. / AFRIKAANSE OPSOMMING: Ploegverwerking is ‘n algemene remediëringsmetode vir die verwerking van afvalmateriaal in petrochemiese industrieë. Dit behels die inploeg van toksiese afvalmateriaal in die boonstegrondlaag sodat dit biologies afgebreek kan word. ‘n Voorbeeld van ‘n histories ploegverwerkte grondstuk is geidentifiseer by ‘n Suid-Afrikaanse olieraffinadery. Die raffinadery het in die verlede van die grondstuk gebruik gemaak om sogenaamde Amerikaanse Petroleum Instituut-slik (API-slik) daarin te ploeg. Die API-slik bestaan uit ‘n mengsel van olie- en wateroplosbare kontaminante afkomstig van die proses waardeur die raffinadery se afvalprodukte van hernubare water en olie geskei word. Nadat oormatige konsentrasies slik in die grond ingewerk is en bioremediasie nie meer doeltreffend kon voortgaan nie, is die ploegverwerking gestaak. ‘n Omgewingimpakstudie moes uitgevoer word om te bepaal tot watter mate die grond herstel het nadat remediasie oor tyd uitgevoer is.
Toksisiteitstoetse en chemiese analises is uitgevoer om die vlakke van besoedeling sowel as die biobeskikbare fraksie daarvan in die grond te bepaal. Die ploegverwerkte area van die raffinadery is in twee verdeel naamlik, ‘n meer gekontamineerde noordelike area en ‘n minder gekontamineerde suidelike area. Grondmonsters is van die onderskeie areas asook van ‘n ongekontamineerde veld (as kontrole) naby die ploegverwerkte area versamel Die gronde is fisies- en chemies geanaliseer en toksisiteitstoetse is uitgevoer. Twee addisionele kontolegronde is ook tydens die blootstellings gebruik naamlik, OECD- en LUFA2.2-grond.
Die chemiese analises van die ploegverwerkte toetsgronde het getoon dat daar steeds swaarmetale en hoë vlakke van dieselgekoppelde organiese koolwaterstowwe in die gronde teenwoordig is. Kontaminante was in hoër konsentrasies teenwoordig in die grond van die noordelike gebied as in dié van die suidelike gebied.
Drie spesies van grondorganismes is gebruik tydens standaard toksisitetitstoetse. Eisenia andrei, Enchytraeus doerjesi en Folsomia candida is blootgestel aan die onderskeie toets- en kontrolegronde waarna hul oorlewing, groei, voortplantingsukses en vermydingsreaksies bestudeer is. Blootstellings aan die ploegverwerkte toetsgronde het geen akute toksisiteit vir enige van die spesies getoon nie. F. candida se juveniele produksie was laer in beide noordelike- en suidelike toetsgronde (289.42 ± 58.62 en 253.33 ± 122.94 onderskeidelik) as in die kontolegrond (479.89 ± 30.42). E. doerjesi blootstellings het ‘n toename in juveniele getalle getoon in die noordelike- en suidelike toetsgronde (339.75 ± 76.92 en 414.00 ± 17.78) in vergelyking met die
ongekontamineerde kontolegrond (57 ± 34.39). Kokonproduksie by E. andrei was soorgelyk in die suidelike toetsgrond en ongekontamineerde kontrolegronde (19.00 ± 5.3 en 18.5 ± 9.7 onderskeidelik) maar beduidend minder as in noordelike toetsgrond (1.25 ± 0.7). Slegs E. doerjesi het ‘n beduidende vermydingsreaksie vir die noordelike toetsgronde getoon.
Om die sensitiwiteit van die organismes aan vars API-slik te bestudeer, is hulle blootgestel aan konsentrasiereekse van API-slik in die onderskeie kontrolegronde. Die effektiewe konsentrasie (EK50) is bereken as die konsentrasie van API-slik wat die bestudeerde eindpunte met 50% sal verminder in vergelyking met die kontrolegrond Die EK50-waardes vir al die spesies het verskil na blootstelling aan die onderskeie kontrolegronde. Dus, die toksisiteit van die API-slik is tot ‘n sekere mate ook afhanklik van die fisiese grondeienskappe van die blootsellingssubstraat. Die voortplanting van F. candida was die gevoeligste eindpunt vir die blootstelling aan API-slik in kontolegrond (EK50 = 90 mg/kg) en E. doerjesi was die minste gevoelig in LUFA2.2 grond (EK50 = 36000 mg/kg).
Vyf plantspesies is ook blootgestel aan API-slikgekontamineerde potgrond en die saadontkiemingssukses, vroeë groeikoers en biomassa is bestudeer. Alhoewel plante nie so sensitief was vir die API-slik soos die gronddiere nie, was blaarslaai en gras die meeste geaffekteer tydens die blootstellings. Boontjies was die ongevoeligste en met die toevoeging van lae konsentrasies API-slik (2.5% API-slik), is hul groeikoers selfs gestimuleer.
Uit die studie was dit duidelik dat die suidelike deel van die grondstuk meer suksesvol as die noordelike geremidieer is en dat meeste grondorganismes wat daaraan bloot gestel is nie geaffekteer is deur die vlakke van kontaminasie wat steeds teenwoordig is in die grond nie. Die toetsgronde uit die noordelike deel het egter steeds negatiewe effekte op die grondorganismes gehad. Dit word voorgestel dat die koolwaterstof kontaminasie verder geremidieër behoort te word in die noordelike deel van die grondstuk voordat verdere ploegverwerking van die afval daar gedoen word.
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Influência do ambiente sobre os limiares de percepção e de tolerância à dor dentária: um estudo psicofísico. / Influence of environment on pain perception and pain tolerance thresholds: a psychophysics study.Canto-Pereira, Luiz Henrique Mourão do 09 September 1997 (has links)
O objetivo principal do presente estudo foi verificar a influência do ambiente sobre o limiar de percepção de dor (LPD) e limiar de tolerância à dor (LTD),através da estimulação elétrica da polpa dentária no incisivo central superior hígido. Os experimentos foram realizados em dois ambientes, o de atendimento odontológico (Odonto) e uma situação neutra (Neutro), desprovida de equipamentos odontológicos. Foram utilizados 50 pacientes, entre 30 e 40 anos de idade, em atendimento na clínica odontológica da Faculdade de Odontologia da Universidade de São Paulo, distribuídos em 4 grupos Odonto-Questionário- Experimento (OQE), Neutro-Questionário-Experimento (NQE), Odonto-Experimento-Questionário (OEQ) e Neutro-Experimento-Questionário (NEQ). Foram utilizados os testes psicométricos Escala de Ansiedade Dentária e Inventário de Ansiedade Traço-Estado para mensuração da ansiedade. Foram realizadas 5 séries de estimulação elétrica para a determinação do LPD e uma única série ascendente para a determinação do LTD. À base dos dados experimentais obtidos pode-se concluir que: - A situação que simula a de atendimento odontológico provoca maior sensibilidade dolorosa e menor tolerância à dor nos sujeitos; existindo correlação positiva entre LPD e LTD. - A razão de tolerância à dor (LTD / LPD) encontrada se situa entre 1,36 a 1,48:1. - Há maior sensibilidade dolorosa frente à 1ª série de estimulação sugerindo a participação do foco de atenção do sujeito frente à estimulação dolorosa, talvez como o principal fator na modulação da resposta dolorosa. - A Escala de Ansiedade Dentária é o instrumento psicométrico que permite a identificação de pacientes que apresentem níveis de ansiedade dentária exacerbada. / The main purpose of the present study was to verify the influence of the enviroment on the pain perception threshold (PPT) and pain tolerance threshold (PTT), through tooth pulp electrical stimulation performed at the intact superior central incisor. Experiments were performed in two enviroments: at the dental office (Dental) and at neutral room (Neutral) without any dental equipment. Fifty patients, between 30 to 40 years old, currently under dental treatment at the dental clinic of the Faculdade de Odontologia da Universidade de São Paulo, were distributed into 4 groups: Dental-Questionnaire-Experiment (DQE), Neutral-Questionnaire-Experiment (NQE), Dental-Experiment-Questionnaire (DEQ) and Neutral-Experiment-Questionnaire (NEQ). The psychometric test - Dental Anxiety Scale and State-Trait Anxiety Inventory - were used to measure the anxiety level of the patients. Five series of electrical stimulation were performed to measure PPT and one upward series to measure PTT. On the basis of the experimental data it is concluded that: - The situation that simulated a dental treatment promote more pain sensitivity and less pain tolerance; there is a positive correlation between PPT and PTT. - The tolerance pain ratio (PTT/PPT) found is located at the interval 1,36 and 1,48:1. - There is more pain sensitivity in the first stimulation series suggesting that the attention focus towards the painful stimulation has an important role in pain sensitivity, possibly as a major aspect in the modulation of pain response. - The Dental Anxiety Scale was found to be the psychometric test that allowed the identification of patients with high dental anxiety levels.
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Nutrients in Pirron Yallock Creek, southwestern Victoria : paleolimnological and management considerations.Duthie, Troy, mikewood@deakin.edu.au January 2000 (has links)
The concentrations of various forms of nitrogen and phosphorus in the main stream and selected tributaries of Pirron Yallock Creek, southwestern Victoria were examined over a two-year period. Exceedingly high levels of both nutrients were found within a particular tributary, while generally high nutrient levels were observed throughout the catchment. The speciation results indicated that dairy effluent was the primary source of nutrients to Pirron Yallock Creek.
A palaeolimnological study was undertaken to determine the impact of European settlement upon waterway nutrient concentrations within the region. The palaeolimnological study focused primarily on the diatom flora preserved within the sediments of nearby Lakes Corangamite and Bullen Merri. Lack of preservation of diatoms within the sediments of Lake Corangamite resulted in no water quality inferences for this lake. The preserved diatoms within Lake Bullen Merri suggested an increase in trophic status of this lake during the last 500 years. While a change in the diatom flora of Lake Bullen Merri was evident, it was not possible to differentiate the impact of European settlement upon nutrient status of this waterway from long-term trophic status change.
In light of the particularly high nutrient concentrations observed in Pirron Yallock Creek, improved nutrient management strategies are proposed for the catchment. These strategies, which consider current nutrient management activities, are predominantly focussed on the dairy industry, which occupies the majority of the catchment.
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Prediction Techniques Of Acid Mine Drainage: A Case Study Of A New Poly- Metallic Mine Development In Erzincan-ilic, TurkeySezer Ozcelik, Ganime Asli 01 February 2007 (has links) (PDF)
Acid Mine Drainage (AMD) is an environmental problem that eventually occurs in
sulfide rich mine sites. In Turkey most of the metal mines are associated with
sulphide minerals and are potential AMD generators. The purpose of this PhD thesis
is to practice universally accepted tools for the prediction of AMD potential for a new
metallic mine development.
This study involves evaluation of geological data, geochemistry, mineralogy, and
acid-base accounting (static tests) data, obtained from the Erzincan-iliç / Ç / ö / pler Gold
Prospect case.
The mineralization in Ç / ö / pler is in sulfide and oxide types. The oxide is a supergene
alteration and porphyry-copper type gold mineralization is classified as an
intermediate sulfidation. The major lithologies observed in the study area are the
regionally un-correlated meta-sedimentary lithologies, Munzur Limestone, and the
Ç / ö / pler Granitoid.Thirty-eight representative samples were tested for AMD prediction purposes.
Sixteen more were included to the sampling scheme for site characterization.
Both acid producing and neutralizing lithologies are present in the mine site.
Similarly it was revealed that the sulphate sulfur content of the samples were
insignificant that any determined total sulfur amount can be directly considered as
the factor for AMD production.
Geochemical data revealed arsenic enrichments up to 10000 ppm in the study area.
Therefore, during the operational stage, in addition to the planning to avoid or
minimize AMD, it is necessary to take precautions against arsenic mobilization
during the design of the AMD neutralization scheme.
Both Kinetic studies and the heavy metal mobilization related to AMD are kept out of
the scope of this investigation. Similarly, management and abatement stages of
AMD are excluded.
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Comparison Of Iscst3 And Aermod Air Dispersion Models: Case Study Of Cayirhan Thermal Power PlantDolek, Emre 01 December 2007 (has links) (PDF)
In this study, emission inventory was prepared and pollutant dispersion studies were carried out for the area around Ç / ayirhan Thermal Power Plant to determine the effects of the plant on the environment. Stack gas measurement results were used for the emissions from the power plant and emission factors were used for calculating the emissions from residential sources and coal stockpiles in the study region. Ground level concentrations of SO2, NOx and PM10 were estimated by using EPA approved dispersion models / namely ISCST3 and AERMOD.
The ground level concentrations predicted by two models were compared with the results of ambient air pollution measurements for November 2004. Predictions of both ISCST3 and AERMOD were underestimating the ground level SO2
concentrations. However, AERMOD predictions are better than ISCST3 predictions. The results of both models had good correlation with the results of NOx measurements. It has been shown that the contribution of the power plant to SO2, NOx and PM10 pollution in the area studied is minimal.
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Improvements In Energy And Water Consumption Performances Of A Textile Mill After Bat ApplicationsKocabas, Ayse Merve 01 February 2008 (has links) (PDF)
European Union& / #8217 / s Integrated Pollution Prevention and Control (IPPC) Directive forms a comprehensive framework for industries mentioned in the Annex 1 of the Directive concentrating on the reduction of the environmental impacts of the industrial activities which can be implemented by the BREF Documents that provide guidelines for each sector. Among those industries, textile is a water and energy intensive one. In the present study, gains in terms of energy and water consumptions were assessed in a denim producing textile mill following the adaptation of related BAT measures. In this respect, installation of flow meters, use of semi-counter current rinsing applications / minimization of wash waters in the water softening plant, reuse of concentrate stream from reverse osmosis plant and compressor cooling waters resulted in reduction from 6,000 to 4,850 tone/day of total water consumption in the period of January& / #8217 / 05-December& / #8217 / 07. Consequently, specific water consumption in the mill was decreased from 78 to 55 L/kg textile by 29:5% which is close to lower limit of the range suggested in BREF Textile Document (i.e. 50-100 L/kg fabric). Use of waste heat from finishing wastewater streams in heating up the washing waters, heat-insulation and maintenance applications in addition to BAT measures taken for water minimization reduced specific energy consumption from 0.0100 to 0.0091 Gcal/kg textile resulting in 9% reduction in the period of January& / #8217 / 05-December& / #8217 / 07, although, energy consumption was increased from 786 to 804 Gcal/day. This achieved level of specific energy consumption was in the reference range mentioned in BREF Textile Document (i.e. 8-20 kWh/kg fabric).
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