975 resultados para Mature landfill leachates


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Mobiltelefonen uppfanns år 1970, den förta komerciella produkten lanserades 1983 och marknaden för mobiltelefoner tog kraftigt fart 1986. Exemplet belyser fenomenet innovation såsom ett mångårigt, ofta upptill tio år eller årtionden, vilket är forkningsansatsen i doktorsavhandlingen. Studien har betraktat fenomenet utgående från ett företagsledningsperspektiv, inte som ett innovations projekt vilket är det trditionella perspektivet. Forskningen bygger vidare på kritiken mot den allmänna uppfattningen att nystartade små och entrepreneursdrivna företag är idealomgivningen för innovation. I forskningen har studerats gamla och stora innovativa konsumentvaruföretag. De sex studerade företagen drivs inte längre av företagets grundare, hans tankar, nätverk, ledningssätt, utan är mera influerat av strukturer, system och prosesser som och iståndsatts av en annan professionell ledning. Denna ledning har i viss mån förmått att professionalisera sättet hur innovation hanteras framgångsrikt i företaget. I forskningen har den innovativa företagsledningens tankevärld och dynamiken i tänkandet definierats. Genom studien framkommer dels tre påtagliga tankemönster och dels en generell beskrivning av ledningen för ett innovativt företag. Kärnan i arbetet definierar ledningens uppmärksamhetsområde vilket är kritiskt för att det innovativa tillståndet och cykeln för innovation har fortbestått. Innovationsaktivisternas roll är avgörande, där produkten formas som en funktion av idéer som någon har och jobbar med, av beslutsfattadet i företaget, samt av tolkning och slutledningen av företagets gällande och framtida verksamhetsvilkor. Detta kritiska uppmärksamhetsområde har även testats och verifierats i avhandlingen. Ur forskningen framstår belägg och ett förslag till en teori, med vilken det är möjligt att förklarar skillnaden i ledningens tänkande vid betraktelsen av de innovativa företagen och de icke-innovativa företagen.

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ABSTRACT This study aimed to estimate the genetic correlation among selection ages (juvenile - adult) and efficiency of early selection for the height, diameter, and volume traits of individuals from Pinus taeda families propagated via somatic embryogenesis. This study was carried out by genetic-statistical analysis, estimation procedure of variance (Reml), and prediction components of breeding values (Blup), using the Selegen-Reml/Blup software. Genetic correlations among juvenile ages and rotation age were performed by applying the linear model developed by Lambeth (1980). In accordance with results of the established model, the early selection can be performed in clones of Pinus taeda with high selection efficiency. Ages from 4 to 6 years old are enough to select Pinus taeda clones propagated via somatic embryogenesis for harvesting at 8 and 12 years old; and 6 to 10 years old are enough to select them for harvesting at 20 years old. On the basis of the genetic correlations estimates from the environments, the clones' selection of Pinus taeda propagated via somatic embryogenesis should be developed specifically for each environment. The clones' selection can be performed considering the diameter due to the high correlation between volume and diameter.

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Storage substances such as starch grains, proteins and lipids were studied during the male gametogenesis and in the mature pollen grain of Ilex paraguariensis St. Hil. (Aquifoliaceae). There are two cycles of amylogenesis and amylolyse. The first cycle lasts until the vacuolated stage when the starch is hydrolyzed and amorphous proteins are stored inside the single vacuole. The next cycle begins after mitosis with the formation of the vegetative and generative cells. At this point, the young vegetative cell stores many starch grains that are bigger than in the first cycle. During the maturation of the male gametophyte, the starch is hydrolyzed and it is absent in the mature pollen grain. Small lipid droplets surround the young generative cell after the mitosis of the androspore and are dispersed in the vegetative cytoplasm during its maturity. The relationship between the pollen storage substances and the ontogeny of the layers in the sporoderm, formation of the generative cell, and the male germ unit were discussed.

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Sapindus saponaria (soapberry) is a species that presents a great diversity of chemical compounds, such as saponins; however, few studies have examined the allelopathic effect of this species. Therefore, this study provides an evaluation of the allelopathic potential of aqueous extracts of the roots and mature leaves of S. saponaria on the germination of diaspores and seedlings growth of lettuce (Lactuca sativa) and onion (Allium cepa). The aqueous extract was prepared in the proportion of 100 g of dry plant material in 1,000 mL of distilled water (a concentration of 10% w v-1), and diluted with distilled water to 7.5, 5.0 and 2.5% concentrations. The mature leaf extracts caused delay and decrease in the germination process of the lettuce and onion diaspores, with inhibitory effect concentration-dependent, while the root extracts showed no allelopathic effects on the germination process. Both extracts caused abnormalities and inhibited the growth of shoot and root seedlings.

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In tumor-bearing rats, most of the serum amino acids are used for synthesis and oxidation processes by the neoplastic tissue. In the present study, the effect of Walker 256 carcinoma growth on the intestinal absorption of leucine, methionine and glucose was investigated in newly weaned and mature rats. Food intake and carcass weight were decreased in newly weaned (NT) and mature (MT) rats bearing Walker 256 tumor in comparison with control animals (NC and MC). The tumor/carcass weight ratio was higher in NT than in MT rats, whereas nitrogen balance was significantly decreased in both as compared to control animals. Glucose absorption was significantly reduced in MT rats (MT = 47.3 ± 4.9 vs MC = 99.8 ± 5.3 nmol min-1 cm-1, Kruskal-Wallis test, P<0.05) but this fact did not hamper the evolution of cancer. There was a significant increase in methionine absorption in both groups (NT = 4.2 ± 0.3 and MT = 2.0 ± 0.1 vs NC = 3.7 ± 0.1 and MC = 1.2 ± 0.2 nmol min-1 cm-1, Kruskal-Wallis test, P<0.05), whereas leucine absorption was increased only in young tumor-bearing rats (NT = 8.6 ± 0.2 vs NC = 7.7 ± 0.4 nmol min-1 cm-1, Kruskal-Wallis test, P<0.05), suggesting that these metabolites are being used for synthesis and oxidation processes by the neoplastic cells, which might ensure their rapid proliferation especially in NT rats.

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The objective of the present study was to examine the association between follicular fluid (FF) steroid concentration and oocyte maturity and fertilization rates. Seventeen infertile patients were submitted to ovulation induction with urinary human follicle-stimulating hormone, human menopausal gonadotropin and human chorionic gonadotropin (hCG). A total of 107 follicles were aspirated after hCG administration, the oocytes were analyzed for maturity and 81 of them were incubated and inseminated in vitro. Progesterone, estradiol (E2), estrone, androstenedione, and testosterone were measured in the FF. E2 and testosterone levels were significantly higher in FF containing immature oocytes (median = 618.2 and 16 ng/ml, respectively) than in FF containing mature oocytes (median = 368 and 5.7 ng/ml, respectively; P < 0.05). Progesterone, androstenedione and estrone levels were not significantly different between mature and immature oocytes. The application of the receiver-operating characteristic curve statistical approach to determine the best cut-off point for the discrimination between mature and immature oocytes indicated levels of 505.8 ng/ml for E2 (81.0% sensitivity and 81.8% specificity) and of 10.4 ng/ml for testosterone (90.9% sensitivity and 82.4% specificity). Follicular diameter was associated negatively with E2 and testosterone levels in FF. There was a significant increase in progesterone/testosterone, progesterone/E2 and E2/testosterone ratios in FF containing mature oocytes, suggesting a reduction in conversion of C21 to C19, but not in aromatase activity. The overall fertility rate was 61% but there was no correlation between the steroid levels or their ratios and the fertilization rates. E2 and testosterone levels in FF may be used as a predictive parameter of oocyte maturity, but not for the in vitro fertilization rate.

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The purpose of this thesis was to investigate environmental permits of landfills with respect to the appropriateness of risk assessments focusing on contaminant migration, structures capable to protect the environment, waste and leachate management and existing environmental impacts of landfills. According to the requirements, a risk assessment is always required to demonstrate compliance with environmental protection requirements if the environmental permit decision deviates from the set requirements. However, there is a reason to doubt that all relevant risk factors are identified in current risk assessment practices in order to protect people end environment. In this dissertation, risk factors were recognized in 12 randomly selected landfills. Based on this analysis, a structural risk assessment method was created. The method was verified with two case examples. Several development needs were found in the risk assessments of the environmental permit decisions. The risk analysis equations used in the decisions did not adequately take into account all the determining factors like waste prospects, total risk quantification or human delineated factors. Instead of focusing on crucial factors, the landfill environmental protection capability is simply expressed via technical factors like hydraulic conductivity. In this thesis, it could be shown, that using adequate risk assessment approaches the most essential environmental impacts can be taken into account by consideration of contaminant transport mechanisms, leachate effects, and artificial landfill structures. The developed structural risk analysing (SRA) method shows, that landfills structures could be designed in a more cost-efficient way taking advantage of recycled or by-products. Additionally, the research results demonstrate that the environmental protection requirements of landfills should be updated to correspond to the capability to protect the environment instead of the current simplified requirements related to advective transport only.

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This study examined the impact of habitat restoration on bee communities (Hymenoptera: Apidae) of the Niagara Region, Ontario, Canada. Bee abundance and diversity was studied in three restored landfill sites: the Glenridge Quarry Naturalization Site (GQNS) in St. Catharines, Elm Street Naturalization Site in Port Colborne, and Station Road Naturalization Site in Wainfleet during 2011 and 2012. GQNS represented older sites restored from 2001-2003. Elm and Station sites represented newly restored landfills as of 2011. These sites were compared to control sites at Brock University where bee communities are well established and again to other landfills where no stable habitat was available before restoration. The objective of this study is to investigate the impact of restoration level on bee abundance and diversity in restored landfill sites of the Niagara Region. Based on the increased disturbance hypothesis (InDH) and the intermediate disturbance hypothesis (IDH), I hypothesized that bee abundance and diversity will follow two patterns. First pattern according to InDH suggest that as the disturbance decrease the bee abundance and diversity will increased. Second pattern according to the IDH bee abundance and diversity will be the highest at the intermediate level of disturbance. A total of 7 173 bees were collected using pan traps and flower collections, from May to October 2011 and 2012. Bees were classified to five families, 21 genera and sub-genera, containing at least 78 species. In 2011 bee abundance was not significantly different among restoration levels while in 2012 bee abundance was significant difference among restoration level. According to family there were no significant difference in Halictidae and Apidae abundance among restoration level while Colletidae and Megachilidae abundance were varied among restoration levels. The bee species richness was highest in the newly restored sites followed by restored control sites, and then the control site. The current study demonstrates that habitat restoration results in rapid increases in bee abundance and diversity for newly restored sites, and, further, that it takes only 2-3 years for bee assemblages in newly restored sites to arrive at the same levels of abundance and diversity as in nearby control sites where bee communities are well established.

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Thèse numérisée par la Division de la gestion de documents et des archives de l'Université de Montréal.

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Leachate from an untreated landfill or landfill with damaged liners will cause the pollution of soil and ground water. Here an attempt was made to generate knowledge on concentrations of all relevant pollutants in soil due to municipal solid waste landfill leachate and its migration through soil and also to study the effect of leachate on the engineering properties of soil. To identify the pollutants in soil due to the leachate generated from municipal solid waste landfill site, a case study on an unlined municipal solid waste landfill at Kalamassery has been done. Soil samples as well as water samples were collected from the site and analysed to identify the pollutants and its effect on soil characteristics. The major chemicals in the soil were identified as Ammonia, Chloride, Nitrate, Iron, Nickel, Chromium, Cadmium etc.. Engineering properties of field soil samples show that the chemicals from the leachate of landfill may have effect on the engineering properties of soil. Laboratory experiments were formulated to model the field around an unlined MSW landfill using two different soils subjected to a synthetic leachate. The Maximum change in chemical concentration and engineering property was observed on soil samples at a radial distance of 0.2 m and at a depth of 0.3 m. The pollutant (chemicals) transport pattern through the soil was also studied using synthetic leachate. To establish the effect of pollutants (chemicals) on engineering properties of soil, experiments were conducted on two types soils treated with the synthetic chemicals at four different concentrations. Analyses were conducted after maturing periods of 7, 50, 100 and 150 days. Test soils treated with maximum chemical concentration and matured for 150 days were showing major change in the properties. To visualize the flow of pollutants through soil in a broader sense, the transportation of pollutants through soil was modeled using software ‘Visual MODFLOW’. The actual field data collected for the case study was used to calibrate the modelling and thus simulated the flow pattern of the pollutants through soil around Kalamassery municipal solid waste landfill for an extent of 4 km2. Flow was analysed for a time span of 30 years in which the landfill was closed after 20 years. The concentration of leachate beneath the landfill was observed to be reduced considerably within one year after closure of landfill and within 8 years, it gets lowered to a negligible level. As an environmensstal management measure to control the pollution through leachate, permeable reactive barriers are used as an emerging technology. Here the suitability of locally available materials like coir pith, rice husk and sugar cane bagasse were investigated as reactive media in permeable reactive barrier. The test results illustrates that, among these, coir pith was showing better performance with maximum percentage reduction in concentration of the filtrate. All these three agricultural wastes can be effectively utilized as a reactive material. This research establishes the influence of leachate of municipal solid waste landfill on the engineering properties of soil. The factors such as type of the soil, composition of leachate, infiltration rate, aquifers, ground water table etc., will have a major role on the area of influence zone of the pollutants in a landfill. Software models of the landfill area can be used to predict the extent and the time span of pollution of a landfill, by inputting the accurate field parameters and leachate characteristics. The present study throws light on the role of agro waste materials on the reduction of the pollution in leachate and thus prevents the groundwater and soil from contamination