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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
11

Estudo dos efeitos combinados de gonadotrofinas e flushing em marrãs à puberdade / Combined effects of gonadotropin and flushing in pubertal gilts

Volnei do Lago 05 December 2003 (has links)
O objetivo do estudo realizado no Laboratório de Pesquisa em Suínos, da Faculdade de Medicina Veterinária e Zootecnia da Universidade de São Paulo, Pirassununga – SP, foi verificar os efeitos combinados de gonadotrofinas exógenas, (eCG e LH) e flushing sobre a duração e dispersão da manifestação do primeiro e segundo estros, ciclicidade das fêmeas, número de ovulações, viabilidade embrionária e freqüência de cistos ovarianos. Foram utilizadas 72 marrãs pré-púberes da linhagem Pen Ar Lan NAIMA®, com idade média de 157,49±5,01 dias, e 96,65±7,70kgs de peso, distribuidas em quatro tratamentos, em arranjo fatorial, com e sem flushing , e com e sem hormônio. A ração utilizada continha 16% de PB e 3.286,73 kcal/kg ME. A partir do 7º dia do primeiro estro, induzido com hormônio, as fêmeas do tratamento com flushing receberam 50% de incremento da mesma ração. No 16º dia, após o primeiro estro, as marrãs no tratamento hormonal receberam aplicação de 600 UI de eCG (Novormon®) e 2,5 mg de LH (Lutropin®), 72 horas após. Todas as marrãs foram expostas ao macho duas vezes ao dia, a partir do 10º dia e inseminadas ao segundo estro com sêmem heterospérmico contendo 4 x 109 espermatozóides. Ao abate, realizado no 5º dia após a inseminação, os genitais foram colhidos para exame dos ovários e coleta dos embriões. Não se observou interação entre os fatores. Os efeitos analisados em separado, não evidenciaram diferença significativa no Número de ovulações (14,28±5,06 vs 13,47±5,57 com e sem Flushing e 14,60±5,78 vs 13,23±4,83 com e sem Hormônio, respectivamente, P>0,05), na freqüência de cistos ovarianos (22,86% vs 11,11%, com e sem Flushing e 15,15% vs 18,42%, com e sem Hormônio, respectivamente,. P>0,05), na Manifestação do 2º estro (85,71% vs 91,43% com e sem Flushing e 90,63% vs 86,84% com e sem Hormônio, respectivamente, P>0,05), no Peso Final (115,35±8,23 vs 111,56±8,30kg, com e sem Hormônio, respectivamente, P>0,05), na Espessura de toucinho (10,0±2,0 vs 10,2±1,8mm com e sem Hormônio, respectivamente, P>0,05), e na Duração dos estros (57,68±20,02 vs 59,68±14,76 horas, com e sem Hormônio e 57,75±14,99 vs 59,62±19,43 horas, com e sem Flushing, respectivamente, P>0,05). Constatou-se diferença significativa na Viabilidade embrionária (11,55±4,81 vs 8,50±5,32 embriões viáveis, com e sem Flushing e 8,39±5,66 vs 11,25±4,58 embriões viáveis, com e sem Hormônio, respectivamente P=0,02), indicando valor superior para o tratamento com Flushing e inferior no grupo com Hormônio. No Peso final (117,48±9,82 vs 109,28±7,57kg, com e sem Flushing, respectivamente, P=0,0001) e na Espessura de toucinho (10,7±2,2 vs 9,5±1,9kg, com e sem Flushing, respectivamente, P=0,03) o valor superior ficou para o grupo com Flushing. Concluiu-se no estudo a não interação dos efeitos, entre os fatores Hormônio e Flushing . O uso das gonadotrofinas (eCG e LH) reduziu a dispersão de manifestação do segundo estro, sendo efetiva a sua sincronização. O emprego do Flushing no primeiro ciclo estral em marrãs influenciou positivamente a viabilidade embrionária e na associação do eCG e LH mais Flushing não notou-se efeito interativo, identificando-se diminuição da viabilidade embrionária, pela ação hormonal. / The objective of this study, held at the Swine Research Laboratory of the School of Veterinary Medicine and Zootechnology of the Univ. of São Paulo in Pirassununga, São Paulo, was to verify the combined effects of exogenic gonadotropin (eCG and LH) and flushing on the duration and dispersion of the manifestation of initial and second estruses, cyclicity of females, number of ovulations, embryonic viability, and frequency of ovarian cysts. Used for the experiment were 72 pubertal gilts of Pen Ar Lan NAIMA® lineage, with an average age of 157.49±5.01 days, and weight of 96.65±7.70kg. They were distributed in four treatments in a factorial arrangement, with and without flushing, and with and without hormone treatment. The feed used contained 16% CP and 3,286.73 kcal/kg ME. Starting on the seven day of the first estrus, induced with homone, the females with flushing treament received a 50% increase in the amount of the same type feed that they had been receiving. On the sixteenth day of the first estrus the gilts that received hormone treatment were given 600 UI of eCG (Novormon®) and 2.5 mg of LH (Lutopin®), 72 hours later. All the gilts were exposed to boar twice at day, starting on the tenth day and inseminated during the second estrus with heterospermic semen containing 4 x 109 spermatozoon. At slaughter on the fifth day after insemination, the genitals were removed to examine the ovaries and collect the embryos. Interaction between the factors were not observed. The effects that were analyzed separately did not show significant differences in the number of ovulations (14.28±5.06 vs 13.47±5.57 with and without flushing, and 14.60±5.78 vs 13.23±4.83 with and without hormones, respectively, P>0.05), in the frequency of ovarian cysts (22.86% vs 11.11%, with and without flushing and 15.15% vs 18.42% with and without hormones, respectively, P>0.05), during the second estrus (85.71% vs 91.43% with and without flushing and 90.63% vs 86.84% with and without hormones respectively, P>0.05), at final weight (115.35 ± 8.23 vs 111.56 ± 8.30kg, with and without hormones, respectively, P>0.05), in the backfat (10.0±2.0 vs 10.2±1.8mm with and without hormones, respectively, P>0.05), and in the duration of the estruses (57.68±20.02 vs 59.68±14.76 hours, with and without hormones and 57.75±14.99 vs 59.62±19.43 hours, with and without flushing, respectively, P>0.05). A significant difference was found in embryonic viability (11.55±4.81 vs 8.50±5.32 viable embryos, with and without flushing and 8.39±5.66 vs 11.25±4.58 viable embryos with and without hormones, respectively P=0.02), which indicated higher numbers when treated with flushing and lower numbers when treated with hormones. At the final weight (117.48±9.82kg vs. 109.28±7.57kg with and without flushing respectively, P=0.0001) and in the backfat (10.7±12.2 vs 9.5±1.9kg, with and without flushing, respectively, P=0.03) flushing resulted in a higher number. It is concluded in this study that there is a lack of interactive effects between treaments with hormones and flushing. Utilization of gonadotropins (eCG e LH) reduced the dispersion of the second estrus within an effective synchronization. The utilization of flushing in the first estrous cycle in gilts gave positive results as regards to embryonic viability. The association of eCG and LH, plus flushing did not show an interactive effect, and a reduction was identified in embryonic viability based the action of hormones.
12

THREE-DIMENSIONAL NUMERICAL STUDY ON FREE-FLOW FLUSHING FOR ENHANCING THE EFFICIENCY OF SEDIMENT MANAGEMENT IN RESERVOIRS / ダム貯水池におけるフラッシング排砂効率の向上を目指した三次元河床変動モデルに関する研究

Taymaz, Esmaeili 24 September 2015 (has links)
京都大学 / 0048 / 新制・課程博士 / 博士(工学) / 甲第19292号 / 工博第4089号 / 新制||工||1630(附属図書館) / 32294 / 京都大学大学院工学研究科都市社会工学専攻 / (主査)教授 角 哲也, 准教授 竹門 康弘, 准教授 KANTOUSH Sameh Ahmed / 学位規則第4条第1項該当 / Doctor of Philosophy (Engineering) / Kyoto University / DFAM
13

排砂ゲートに制約された河岸侵食を伴う堆積土砂フラッシュに関する研究

後藤, 孝臣, GOTO, Takaomi, 北村, 忠紀, KITAMURA, Tadanori, 辻本, 哲郎, TSUJIMOTO, Tetsuro 02 1900 (has links)
No description available.
14

Characterization of Mineral Oil, Coal Tar and Soil Properties and Investigation of Mechanisms That Affect Coal Tar Entrapment in and Removal from Porous Media

Kong, Lingjun 12 July 2004 (has links)
Mineral oils and coal tars are complex nonaqueous phase liquids (NAPLs), which can serve as long-term sources of ground water contamination. Very limited data are available on mineral oil and coal tar entrapment in and removal from porous media. Thus, the objectives of this research were to evaluate the behavior of these NAPLs in porous media, and investigate the mechanisms governing NAPL entrapment in and recovery from porous media. Quantification of properties of three commercial mineral oils and six MGP coal tars reveals that mineral oils are slightly viscous LNAPLs (density: ~0.88 g/cm3; viscosity: 10-20 cP), whereas coal tars are highly viscous DNAPLs (density: 1.052-1.104 g/cm3; viscosity: 32-425 cP). Measured oil (tar)-water interfacial tensions (IFT) were lower than that of pure NAPLs. Properties of 16 field soil samples (soil particle size distribution, specific surface area, total carbon content, cationic exchange capacity and soil moisture release curves) were characterized. Correlations between residual NAPL saturation and NAPL and soil properties were developed, and show that the entrapment of NAPL dependent upon soil particle size distribution, total carbon content, NAPL viscosity and NAPL-water IFT. Aqueous pH and ionic strength were found to influence the interfacial properties in tar-water-silica systems. At pHs greater than 7.0, observed reduction in contact angle were attributed to the repulsive electrostatic force between coal tar and solid surface. When pH less than 4, hydration forces played a role on the contact angle decrease. The IFT reduction was resulted from the accumulation of surface-active molecules at the tar-water interface. The effect of ionic strength on interfacial properties was not significant below 0.5 M. The effects of temperature and surfactant or surfactant/polymer addition on coal tar removal was investigated by conducting coal tar displacement experiments at three different temperatures (22, 35, and 50??with sequential flushing of water, surfactant and surfactant/polymer. Coal tar removal from porous media was enhanced by elevating temperature and surfactant flushing due to the viscosity and IFT reduction, respectively. Xanthan gum was used as the polymer to increase the viscosity of the displacing fluid. In summary, these results provide tools for the prediction of NAPL entrapment in porous media, and for the selection of remediation strategies for coal tar contaminated source zone.
15

Formulation and in Vitro Evaluation of Niacinloaded Nanoparticles to Reduce Prostaglandin Mediated Vasodilatory Flushing

Cooper, D. L., Carmical, J. A., Panus, P. C., Harirforoosh, S. 01 January 2015 (has links)
OBJECTIVE: Niacin, activating G-protein coupled receptor (GPR) 109A, stimulates release of vasodilatory prostaglandins (PGs) such as PGE2 which can elicit niacin-associated flushing side effects. Poly-lactic-coglycolic acid (PLGA) and poly-lactic acid (PLA) are used in nanoparticle (NP) drug delivery to reduce adverse effects and modulate drug release. Our study evaluated the in vitro effects of niacin-loaded PLGA or PLA-NPs on PGE2 expression in whole human blood as a model for niacin-induced flushing. MATERIALS AND METHODS: NPs were formulated using a solvent evaporation process and characterized by size, polydispersity, zeta potential, drug entrapment, morphology, and drug release. NP in vitro effects on PGE2 release were measured via ELISA analysis. RESULTS: PLGA-NPs demonstrated the lowest NP size (66.7 ± 0.21 nm) with the highest zeta potential and percent drug entrapment (42.00 ± 1.62 mV and 69.09 ± 0.29%, respectively) when compared to PLA-NPs (130.4 ± 0.66 nm, 27.96 ± 0.18 mV, 69.63 ± 0.03 %, respectively). In vitro release studies showed that PLGA-NPs underwent significant reductions in cumulative drug release when compared to PLA-NPs (p < 0.05). Furthermore, when compared to plain niacin, PLGA-NPs significantly reduced in vitro PGE2 release (p < 0.05). CONCLUSIONS: These results support the use of PLGA-NPs as a novel method of delivery for reducing niacin-associated flushing.
16

Puberdade e a vida útil reprodutiva das fêmeas suínas / Puberty and lifetime reproduction gilts

Santo, Tacia Antunes Del 06 December 2012 (has links)
O presente estudo teve como objetivo verificar o efeito do uso de gonadotrofinas exógenas na indução do estro à puberdade em marrãs, e \"flushing\" alimentar no ciclo estral que antecede a primeira inseminação artificial na vida útil reprodutiva. O experimento foi realizado na Granja Barreiro (Suinocultura Rosetto) Cerqueira César/SP. Foram utilizadas 96 fêmeas da puberdade ao 1° parto, e 68 fêmeas selecionadas das 96 com ordem de parto do primeiro ao sexto para a avaliação associativa com a vida útil reprodutiva. O delineamento experimental foi inteiramente casualizado em um fatorial 2x2 sendo um fator a combinação hormonal H,( 600 UI de eCG e após 72 horas, 2,5 mg de LH porcino) (H) e o estímulo do macho (M). O fator \"flushing\" alimentar correspondeu ao esquema com restrição (R) e o adotado na granja (G). Os tratamentos foram: HR - hormônio e \"flushing\"; HG - hormônio e esquema alimentar da granja; MR - macho e \"flushing\" e MG - macho e esquema alimentar da granja. As informações foram obtidas a partir do banco de dados existente na propriedade onde o experimento foi realizado. As variáveis análisadas foram: número de estros pós-indução, total de nascidos (TN), nascidos vivos (NV), natimortos (NT), mumificados (MM) e intervalo entre partos (ITP). Cinco dias após a aplicação do tratamento hormonal, 31,37% (H) das fêmeas manifestaram características de estro quando comparado ao tratamento M, onde 11,62% apresentaram estro. O tratamento H mostrou maior sincronismo nas manifestações dos estros, diferente do tratamento M que apresentou maior dispersão ao longo dos ciclos. Não houve diferença estatística nas características de primeiro parto entre os tratamentos hormônio e \"flushing\", tanto quanto nas suas interações (P>0,05). Não houve influência dos tratamentos na produtividade dos animais nas diferentes parições (P>0,05). Portanto, apesar do maior sincronismo apresentado pela combinação hormonal em comparação com o estímulo natural somente pela presença do macho, não houve diferenças quanto à produtividade associativa do primeiro parto e demais partos nas características avaliadas. / The present study objective to verify the effect of the use of exogenous gonadotropins in oestrus induction of puberty in gilts, and \"flushing\" feed the estrous cycle before the first artificial insemination in lifetime reproductive. The experiment was conducted at the Granja Barreiro (Swine Rosetto) - Cerqueira César / SP. A total of 96 females from puberty to the 1st delivery, and 68 of the 96 selected females with birth order from first to sixth for assessing association with lifetime reproductive. The experimental design was completely randomized in a 2x2 factorial being a combination hormonal factor H (600 IU eCG and after 72 hours, 2.5 mg porcine LH) (H) and the stimulation of the male (M). The factor \"flushing\" food matched the schema constraint (R) and adopted on the farm (G). The treatments were: HR - hormone and \"flushing\"; HG - hormone regimen and feed the farm; MR - male and \"flushing\" and MG - male and feed the farm scheme. The information was obtained from the existing database on the property where the experiment was conducted. The variables analyzed were: number of post-estrus induction, total born (TN) live births (NV), stillbirths (NT), mummified (MM) and calving interval (ITP). Five days after application of the treatment, 31,37% (H) of estrus females showed characteristics when compared to treatment M, where 11,62% showed estrous. The H treatment showed greater synchronization of estrus in the demonstrations, unlike the M treatment with the highest dispersion along the cycles. There was no statistical difference in the characteristics of first birth among hormone treatments and \"flushing\" as well as their interactions (P>0.05). No influence of the treatments on the productivity of animals in different parities (P>0.05). Therefore, despite the higher timing presented by combination hormonal stimulation compared with only natural for the presence of males, there were no differences in yield associative first birth and other birth characteristics evaluated.
17

Puberdade e a vida útil reprodutiva das fêmeas suínas / Puberty and lifetime reproduction gilts

Tacia Antunes Del Santo 06 December 2012 (has links)
O presente estudo teve como objetivo verificar o efeito do uso de gonadotrofinas exógenas na indução do estro à puberdade em marrãs, e \"flushing\" alimentar no ciclo estral que antecede a primeira inseminação artificial na vida útil reprodutiva. O experimento foi realizado na Granja Barreiro (Suinocultura Rosetto) Cerqueira César/SP. Foram utilizadas 96 fêmeas da puberdade ao 1° parto, e 68 fêmeas selecionadas das 96 com ordem de parto do primeiro ao sexto para a avaliação associativa com a vida útil reprodutiva. O delineamento experimental foi inteiramente casualizado em um fatorial 2x2 sendo um fator a combinação hormonal H,( 600 UI de eCG e após 72 horas, 2,5 mg de LH porcino) (H) e o estímulo do macho (M). O fator \"flushing\" alimentar correspondeu ao esquema com restrição (R) e o adotado na granja (G). Os tratamentos foram: HR - hormônio e \"flushing\"; HG - hormônio e esquema alimentar da granja; MR - macho e \"flushing\" e MG - macho e esquema alimentar da granja. As informações foram obtidas a partir do banco de dados existente na propriedade onde o experimento foi realizado. As variáveis análisadas foram: número de estros pós-indução, total de nascidos (TN), nascidos vivos (NV), natimortos (NT), mumificados (MM) e intervalo entre partos (ITP). Cinco dias após a aplicação do tratamento hormonal, 31,37% (H) das fêmeas manifestaram características de estro quando comparado ao tratamento M, onde 11,62% apresentaram estro. O tratamento H mostrou maior sincronismo nas manifestações dos estros, diferente do tratamento M que apresentou maior dispersão ao longo dos ciclos. Não houve diferença estatística nas características de primeiro parto entre os tratamentos hormônio e \"flushing\", tanto quanto nas suas interações (P>0,05). Não houve influência dos tratamentos na produtividade dos animais nas diferentes parições (P>0,05). Portanto, apesar do maior sincronismo apresentado pela combinação hormonal em comparação com o estímulo natural somente pela presença do macho, não houve diferenças quanto à produtividade associativa do primeiro parto e demais partos nas características avaliadas. / The present study objective to verify the effect of the use of exogenous gonadotropins in oestrus induction of puberty in gilts, and \"flushing\" feed the estrous cycle before the first artificial insemination in lifetime reproductive. The experiment was conducted at the Granja Barreiro (Swine Rosetto) - Cerqueira César / SP. A total of 96 females from puberty to the 1st delivery, and 68 of the 96 selected females with birth order from first to sixth for assessing association with lifetime reproductive. The experimental design was completely randomized in a 2x2 factorial being a combination hormonal factor H (600 IU eCG and after 72 hours, 2.5 mg porcine LH) (H) and the stimulation of the male (M). The factor \"flushing\" food matched the schema constraint (R) and adopted on the farm (G). The treatments were: HR - hormone and \"flushing\"; HG - hormone regimen and feed the farm; MR - male and \"flushing\" and MG - male and feed the farm scheme. The information was obtained from the existing database on the property where the experiment was conducted. The variables analyzed were: number of post-estrus induction, total born (TN) live births (NV), stillbirths (NT), mummified (MM) and calving interval (ITP). Five days after application of the treatment, 31,37% (H) of estrus females showed characteristics when compared to treatment M, where 11,62% showed estrous. The H treatment showed greater synchronization of estrus in the demonstrations, unlike the M treatment with the highest dispersion along the cycles. There was no statistical difference in the characteristics of first birth among hormone treatments and \"flushing\" as well as their interactions (P>0.05). No influence of the treatments on the productivity of animals in different parities (P>0.05). Therefore, despite the higher timing presented by combination hormonal stimulation compared with only natural for the presence of males, there were no differences in yield associative first birth and other birth characteristics evaluated.
18

Evaluating flushing procedures to prevent drug carryover during medicated feed manufacturing

Martinez-Kawas, Adrian January 1900 (has links)
Master of Science / Department of Grain Science and Industry / Leland McKinney / Carryover of medicated feed additives between batches of feed can potentially result in harmful drug residues in the edible tissues of food-animals. Flushing the equipment with an ingredient, such as ground grain, is one method used to remove any residual medicated feed from the system. It is generally recommended that the quantity of flush used be between 5 and 10% of the mixer's capacity. However, there is little data that supports this recommendation. Therefore, two experiments were conducted to 1.)determine which manufacturing equipment is the major source of carryover, 2.)evaluate which flush size adequately prevents drug carryover, and 3.) quantify the interrelationship between flush size and drug concentration. In Experiment 1, feed medicated with nicarbazin (Nicarb 25%®; 0.0125%) was manufactured and conveyed from the mixer, through a drag conveyor and bucket elevator, and then into a finished product bin. The system was then flushed using ground corn in the amount of 2.5, 5, 10, 15, or 20% of the mixer's capacity (454.5 kg). Subsequently, a non-medicated diet was conveyed through the system and samples were collected and analyzed for nicarbazin. No significant (P > 0.05) differences were detected among the flush treatments, and all treatments were effective in preventing nicarbazin carryover to the non-medicated diet. In Experiment 2, feed medicated with three levels of monensin (Rumensin® 80; 100, 600, and 1,200 g/ton) was manufactured and handled in the same manner as in Experiment 1. The flushing treatments examined were: 1, 2.5, and 5% of the mixer's capacity. Samples of the non-medicated diet for each treatment were collected and analyzed for monensin. There was significant interaction (P < 0.05)between drug level and sampling location between treatments. As the drug level in the medicated diet increased, higher concentrations of monensin were detected in the non-medicated diet. Collectively, these studies demonstrate that a 2.5%, even a 1% flush size, is effective in preventing carryover of medicated feed additives. It was also demonstrated that the bucket elevator and finished product bin were the major sources of drug carryover in this particular feed manufacturing system.
19

DNAPL remediation of fractured rock evaluated via numerical simulation

Pang, Ti Wee January 2010 (has links)
Fractured rock formations represent a valuable source of groundwater and can be highly susceptible to contamination by dense, non-aqueous phase liquids (DNAPLs). The goal of this research is to evaluate the effectiveness of three accepted remediation technologies for addressing DNAPL contamination in fractured rock environments. The technologies under investigation in this study are chemical oxidation, bioremediation, and surfactant flushing. Numerical simulations were employed to examine the performance of each of these technologies at the field scale. The numerical model DNAPL3D-RX, a finite difference multiphase flow-dissolution-aqueous transport code that incorporates RT3D for multiple species reactions, was modified to simulate fractured rock environments. A gridding routine was developed to allow the model to accurately capture DNAPL migration in fractures and aqueous phase diffusion gradients in the matrix while retaining overall model efficiency. Reaction kinetics code subroutines were developed for each technology so as to ensure the key processes were accounted for in the simulations. The three remedial approaches were systematically evaluated via simulations in two-dimensional domains characterized by heterogeneous orthogonal fracture networks parameterized to be representative of sandstone, granite, and shale. Each simulation included a DNAPL release at the water table, redistribution to pools and residual, followed by 20 years of ‘ageing’ under ambient gradient conditions. Suites of simulations for each technology examined a variety of operational issues including the influence of DNAPL type and remedial fluid injection protocol. Performance metrics included changes in mass flux exiting, mass destruction in the matrix versus the fractures, and percentage of injected remedial fluid interacting with the target contaminant. The effectiveness of the three remediation technologies covered a wide range; the mass of contaminants destroyed were found to range from 15% to 99.5% of the initial mass present. Effectiveness of each technology was found to depend on a variety of critical factors particular to each approach. For example, in-situ chemical oxidation was found to be limited by the organic material present in the matrix of the rocks, while the efficiency of enhanced bioremediation was found to be related to factors such as the location of indigenous bacteria present in the domain and rate of bioremediation. In the chemical oxidation study, the efficiency of oxidant consumption was observed to be poor across the suite of scenarios, with greater than 90% of the injected permanganate consumed by natural oxidant demand. This study further revealed that the same factors that contributed to forward diffusion of contaminants prior to treatment are critical to this remediation method as they can determine the extent of contaminant destruction during the injection period. Bioremediation in fractured rock was demonstrated to produce relatively good results under robust first-order decay rates and active microorganisms throughout the fractures and matrix. It was demonstrated that under ideal conditions, of the total initial mass present, up to 3/4 could be reduced to ethene, indicating bioremediation may be a promising treatment approach due to the effective penetration of electron donor into the matrix during the treatment period and the ongoing treatment that occurs after injection ceases. However, when indigenous bacteria was assumed to exist only within the fractured walls of sandstone, it was found that under the same conditions, the rate of dechlorination was 200 times less than the Base Case. Since the majority of the mass resided in the matrix, lack of bioremediation in the matrix significantly reduced the effectiveness of treatment. Surfactant treatment with Tween-80 was proven to be a relatively effective technique in enhanced solubilisation of DNAPL from the fractures within the domain. However, by comparing the aqueous and sorbed mass at the start and end of the Treatment stage, it is revealed that surfactant treatment is not efficient in removing these masses that reside within the matrix. Furthermore, DNAPLs identified in dead end vertical fractures were found to remain in the domain by the end of the simulations across all scenarios studied; indicating that the injected surfactant experiences difficulty in accessing DNAPLs entrapped in dead end fractures. Altogether, the results underscore the challenge of restoring fractured rock aquifers due to the field scale limitations on sufficient contact between remedial fluids and in situ contaminants in all but the most ideal circumstances.
20

The flushing effect and expression of follicle stimulating hormone receptor rariants in sheep.

Hand, Jacqelyn M. January 1900 (has links)
Master of Science / Department of Animal Sciences and Industry / Timothy G. Rozell / Timothy G. Rozell / An increase in pre-mating dietary energy positively influences ovulation and lambing rates, and this practice is known as nutritional flushing. The mechanisms of flushing, however, are still unknown. Increasing dietary energy approximately two weeks before breeding likely increases the production of insulin-like growth factor I (IGF-I) within the ovary, which stimulates the synthesis of follicle stimulating hormone receptor (FSHR). Several alternatively spliced transcripts of the FSHR have been identified in sheep. Each variant form is believed to be produced according to the stage of follicle development. This study was carried out to evaluate expression patterns of the FSHR variant forms (FSHR-1, FSHR-2 and FSHR-3) in the sheep ovary in response to different flushing diets. For this experiment, yearling Rambouillet ewes (n=93) were allocated among 6 different energy type treatment diets, either prairie or alfalfa hay based, for at least two weeks in combination with the insertion of a controlled internal drug releasing device (CIDR). Two of the treatment groups had commercially available block supplements provided and two had rolled corn supplemented. Mid-ventral laparotomy was performed on each ewe 3.5 to 4 days after CIDR removal. Follicles 4 mm and greater were aspirated and categorized as either medium (M; 4 to 6 mm) or large (L; > 6 mm). Total RNA was extracted from granulosa cells (GC) and reverse transcribed followed by qPCR of the resulting cDNA using specifically designed primer sets for each variant of the FSHR and for the LH receptor. Changes in live weight were different (P < 0.01) between treatment diets but there were no statistical differences for NEFA concentrations between any of the treatments nor were there differences for body condition (mean = 3.0) or lambing rate. Therefore, it is likely a flushing response did not occur in this study. Expression of FSHR-1was different between M and L follicles (P < 0.01) and tended to be different for ewes fed alfalfa hay (P = 0.05). Overall mean expression of FSHR-3 was greater than expression of FSHR-1 or FSHR-2 (P < 0.01), although there was no difference between M and L follicles, or between treatment diets. The concentration of estradiol in follicular fluid was not different between the treatment diets or follicle sizes nor was expression of lutenizing hormone receptor (LHR), indicating that follicles were similar developmentally. The FSHR-1 form seemed to be the variant most likely to be involved in later stages of follicular development, and is potentially involved in follicle rescue. For all follicles, FSHR-3 was the more highly expressed form of the FSHR and may likely be essential throughout antral follicle development. Further research is required to determine the exact mechanism whereby initial energy status of ewes seems critical for the increased ovulation rate that occurs after energy supplementation (i.e. the flushing response).

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