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The relation of temperature to the effect of hydrogen and hydroxyl ion concentration on Sclerotinia fructicola and Fomes annosus. spore germination and growthTilford, Paul E. January 1935 (has links)
Thesis (Ph. D.)--University of Wisconsin--Madison, 1935. / Typescript. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references.
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Lean implementaiton during a plant consolidationSmolarek, Zenon J. January 2006 (has links) (PDF)
Thesis PlanB (M.S.)--University of Wisconsin--Stout, 2006. / Includes bibliographical references.
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Industrial concentration and the Chicago school of antitrust analysis : a critical evaluation on the basis of effective competition /Rittaler, Jan B. January 1900 (has links)
Th. doct.--University of Hohenheim, 1988. / Bibliogr. p. 351-400.
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Monetary Policy Issues Arising From Bank CompetitionSevere, Sean P. 06 1900 (has links)
xii, 114 p. : ill. / The banking sector has been extensively analyzed in economics. On the microeconomic side, research has advanced our understanding of banks and the inverse relationship between market power and bank production. The macroeconomic side of research has focused on the transmission of monetary policy, and it is understood that the financial system, including banks, plays an integral role in transmitting monetary policy decisions to economic variables such as investment, consumption, and GDP. There is limited understanding, however, about how market power and bank concentration affects the transmission of monetary policy. The main focus of this dissertation is to address this gap in the literature and is achieved by three contributions. First, I develop a theory of banking behavior that accounts for competition and monetary policy. I empirically test the theory and show that banking concentration dampens the impact of monetary policy on lending activity in the short-run. My second contribution involves building a theoretical model with these short-run lending effects incorporated into an endogenous growth model that allows agents, banks, and the central bank to interact. This model shows how short-run lending is tied to growth. Again, monetary policy is less effective in markets with higher concentration. The last contribution is made by empirically testing the second contribution. The empirical findings are consistent with both the first and second contributions; banking markets with less competition adversely affect growth and also diminish the long-run impact of monetary policy. / Committee in charge: Dr. Mark Thoma, Co-Chair;
Dr. Wesley Wilson, Co-Chair;
Dr. Shankha Chakraborty, Member;
Dr. Larry Dann, Outside Member
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Farmacologia clínica da metadona peridural e intravenosa em cãesCampagnol, Daniela [UNESP] 21 January 2011 (has links) (PDF)
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campagnol_d_dr_botfm.pdf: 3603129 bytes, checksum: 6016b81a7cfcb53dc9f89a2b1a5dfcbe (MD5) / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / A metadona é um opióide que possui potência analgésica semelhante à da morfina. Doses elevadas de metadona intravenosa (0,5-1,0 mg/kg), apesar de reduzirem a concentração alveolar mínima do isoflurano (CAMISO), resultam em maior depressão cardíaca que a observada com a morfina intravenosa (1,0 mg/kg) em cães. Com a hipótese de que a metadona peridural poderia proporcionar vantagens clínicas em relação à metadona intravenosa (maior potencialização da anestesia inalatória e maior eficácia analgésica), os estudos apresentados objetivaram comparar aspectos farmacocinéticos e farmacodinâmicos destas vias de administração da metadona em cães. Nos dois estudos iniciais (Capítulos 1 e 2), os mesmos seis animais foram anestesiados com isoflurano e tratados com metadona (0,5 mg/kg) peridural ou intravenosa em ocasiões distintas. No primeiro estudo (Capítulo 1), para comparação da farmacocinética destas duas vias de administração, a concentração de metadona foi determinada no plasma e no líquor da cisterna magna antes e durante 450 minutos após a administração do opióide. No segundo estudo (Capítulo 2), a CAMISO foi mensurada antes e após 2,5 e 5 horas da administração da metadona, mediante a aplicação da estimulação nociceptiva em membro pélvico e torácico (via peridural) ou em membro pélvico apenas (via intravenosa). No último estudo (Capítulo 3), cadelas apresentando tumores mamários, após serem tratadas de forma preemptiva com metadona (0,5 mg/kg) peridural ou intravenosa (10 animais por grupo), foram submetidas à mastectomia unilateral. Nesta etapa, avaliou-se a concentração expirada de isoflurano (ETISO) necessária à realização da mastectomia e, no período pós-operatório, avaliou-se os escores de dor, limiares nociceptivos mecânicos (LNM) das cadeias mamárias e requerimento de resgates analgésicos. No estudo do Capítulo 1, a via... / Methadone is an opioid that has analgesic potency comparable to that of morphine. High doses of intravenous methadone (0.5-1.0 mg/kg), in spite of reducing the minimum alveolar concentration of isoflurane (MACISO), cause greater cardiac depression than intravenous morphine (1 mg/kg) in dogs. The studies presented here aimed to compare some pharmacokinetic and pharmacodynamic aspects of peridural and intravenous methadone in dogs, testing the hypothesis that peridural methadone could result in clinical advantages when compared to intravenous methadone (greater reduction in anesthetic requirements and greater analgesic efficacy). In the first 2 studies (Chapters 1 and 2), the same six animals underwent isoflurane anesthesia and were treated with methadone (0.5 mg/kg) administered via the peridural or intravenous routes during different occasions. During the first study (Chapter 1), in order to compare the pharmacokinetics of these two administration routes, methadone concentrations were determined in plasma and in the cisternal cerebrospinal fluid before and for 450 minutes after opioid injection. During the second study (Chapter 2), MACISO was measured before, 2.5 and 5 hours after methadone injection via nociceptive stimulation of the thoracic and pelvic limb (peridural) or the pelvic limb (intravenous). During the last series of studies (Chapter 3), bitches presented with mammary gland tumors were preemptively treated with peridural or intravenous methadone (0.5 mg/kg) (10 animals per group) and underwent unilateral mastectomy. The end-tidal isoflurane concentration (ETISO) necessary for maintaining surgical anesthesia was evaluated and, during the postoperative period, parameters evaluated included Glasgow pain scores, mechanical nociceptive thresholds (MNT) in the mammary glands, and requirement for supplemental analgesia. In first study (Chapter 1), peridural methadone prolonged... (Complete abstract click electronic access below)
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Efeitos da administração peridural de neostigmina associada ou não a clonidina sobre a concentração alveolar mínima do isoflurano em cãesSisto, Renata Kerche Alvaides [UNESP] 22 February 2010 (has links) (PDF)
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sisto_rka_me_botfm.pdf: 745882 bytes, checksum: 572ac4fa4785affeee08e0c89fedec4c (MD5) / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / Os agentes anticolinesterásicos (neostigmina), quando associados com agonistas de receptores alfa-2 adrenérgicos (clonidina) pela via espinhal, resultam sinergismo no que se refere à analgesia promovida em ratos, ovinos e humanos. Na presente pesquisa, formulou-se a hipótese de que a administração peridural de neostigmina potencializaria a redução da concentração alveolar mínima (CAM) do isoflurano proporcionada pela clonidina peridural em cães. Seis cadelas hígidas (14,9 ± 2,9 kg) foram anestesiadas com isoflurano em 3 ocasiões distintas, com intervalo de 7 dias. Durante as anestesias foi empregada a ventilação controlada a pressão para prevenção da hipercapnia (PaCO2 > 45 mmHg) e a temperatura esofágica foi mantida entre 37,5 a 38,5oC por meios de aquecimento artificiais. Em cada anestesia, os animais receberam aleatoriamente 1 de 3 tratamentos pela via peridural: neostigmina (10 μg/kg), clonidina (20 μg/kg), ou a associação clonidina (20 μg/kg) e neostigmina (10 μg/kg). A CAM do isoflurano, mensurada por meio de estimulação nociceptiva do membro pélvico (50 V, 50 Hz, 10 ms), foi registrada após 2 horas da indução da anestesia (CAM basal) e após 2,5 e 5 horas da administração dos tratamentos peridurais. Em um dos animais, tanto a clonidina como a clonidina/neostigmina resultou em elevação paradoxal da CAM (8-9 %). Nos demais animais estudados (n = 5), os valores de CAM basal (média ± desvio padrão) foram de 1,49 ± 0,26, 1,51 ± 0,23 e 1,49 ± 0,26 vol%, nos tratamentos clonidina, neostigmina e clonidina/neostigmina, respectivamente, não havendo diferença entre tratamentos. As reduções da CAM observadas após a administração peridural de neostigmina não foram significativas (p < 0,05) (reduções percentuais de 11 ± 5% e 8 ± 9% após 2,5 e 5 horas, respectivamente). Houve redução significativa da CAM após a administração peridural de... / Spinal administration of anticholinesterase drugs (neostigmine) in combination with alpha-2 adrenergic receptor agonists (clonidine) results in a synergistic analgesic effect in rats, sheep and humans. The hypothesis of the present study was that the epidural administration of neostigmine would enhance the isoflurane minimum alveolar concentration (MAC) reduction induced by the epidural injection of clonidine in dogs. Six healthy bitches (14,9 ± 2,0 kg ) were anesthetized with isoflurane on 3 distinct occasions, with 7 day intervals among experiments. During the anesthetic episodes, animals were maintained under pressure controlled ventilation to prevent hypercapnia (PaCO2 > 45 mmHg) and esophageal temperature was maintained between 37.5 and 38.5 oC by means of artificial heating devices. During each anesthetic, animals were randomly allocated to receive 1 of 3 epidural treatments: neostigmine (10 μg/kg), clonidine (20 μg/kg), or the combination of clonidine (20 μg/kg) and neostigmine (10 μg/kg). Isoflurane MAC, determined by means of electric stimulation of the pelvic limb (50 V, 50 Hz, 10 ms), was recorded 2 hours after induction of anesthesia (baseline MAC) and 2.5 and 5 hours after epidural injections. In 1 of the animals, clonidine and clonidine/neostigmine caused paradoxical increases in MAC (8-9 % increases). For the remaining animals (n = 5), baseline MAC values (mean ± standard deviation) were 1.49 ± 0.26, 1.51 ± 0.23 e 1.49 ± 0.26 vol%, in the clonidine, neostigmine, and clonidine/neostigmine treatments, respectively. Baseline MAC did not differ among treatments. The isoflurane MAC reductions recorded after epidural injection of neostigmine were not significant (p < 0.05) (percent reductions of 11 ± 5% and 8 ± 9% after 2.5 and 5 hours respectively). The MAC reductions observed after epidural injection of clonidine (35 ± 9% and 22 ± 14% after 2.5 and 5 hours, ... (Complete abstract click electronic access below)
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Efeito da concentração pré e pós-ovulatória de progesterona em protocolos de IATF em fêmeas nelorePeres, Rogério Fonseca Guimarães [UNESP] 04 September 2008 (has links) (PDF)
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peres_rfg_me_botfmvz.pdf: 340579 bytes, checksum: d156d075316c35b86500d5e40a305727 (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Universidade Estadual Paulista (UNESP) / O objetivo desses experimentos foi avaliar os efeitos da concentração de progesterona pré e pós-ovulação em fêmeas Nelore submetidas ao protocolo: D0-benzoato de estradiol (2,0mg, Estrogin®) + CIDR®; D9-retirada do dispositivo + cipionato de estradiol (0,5mg, ECP®) + dinoprost trometamina (PGF2α, 12,5mg, Lutalyse®); D11- IATF. No Exp.1, 1.153 novilhas Nelore cíclicas foram divididas aleatoriamente para receber CIDR® sem utilização prévia ou utilizados previamente por 18 dias e 0, 200 ou 300UI de eCG (Folligon®) no D9. No Exp.2, 702 vacas Nelore solteiras foram divididas para receber aplicação de PGF2α no D7 ou D9 e 0 ou 300 UI de eCG no D9. Nestes experimentos o diâmetro do maior folículo (ØFD) foi avaliado no D11. Amostras de sangue para dosagem de P4 foram colhidas no D9 e D18 (7d pós-IATF). No Exp.3, 1.332 vacas paridas foram avaliadas no D7 quanto à presença de CL, sendo divididas para receber PGF2α no D7 ou D9. Amostras de sangue foram colhidas no D9. O diagnóstico de gestação foi realizado no D41. Variáveis contínuas foram avaliadas pelo PROC GLM e binomiais pelo PROC LOGISTIC. Considerou-se efeito significativo quando P<0,05 e tendência quando P<0,1. No Exp.1, as novilhas tratadas com CIDR® sem utilização prévia apresentaram maior [P4D9] (3,06±0,09 vs. 2,53±0,09 ng/ml). A [P4D9] afetou negativamente o ØFD. Novilhas que não receberam eCG apresentaram menor ØFD (0UI: 11,5±0,1a; 200UI: 11,9±0,1b; 300UI: 12,0±0,1bmm). O ØFD afetou positivamente a [P4D18]. Houve efeito de dose de eCG na [P4D18] (0UI: 2,77±0,11a; 200UI: 3,18±0,11b; 300UI: 4,87±0,11cng/ml) e na taxa de sincronização [TS; 0UI: 83,8%(337/402)a; 200UI:88,5%(339/383)ab; 300UI: 94,3%(347/368)b]. A [P4D9] tendeu a afetar negativamente e o ØFD influenciou positivamente a TS. Houve interação entre eCG e [P4D9] na taxa de... / The aim of this trial was to evaluate the effect of pre- and post-ovulatory progesterone concentration in Nellore cattle treated with the protocol: D0-estradiol benzoate (2.0mg, Estrogin®) + CIDR®; D9–CIDR® withdrawal + of estradiol cypionate (0.5mg, ECP®) + dinoprost trometamine (12.5mg, Lutalyse®); D11-TAI. In Exp.1, 1,153 cycling Nellore heifers were randomly assigned to receive on D0 either a non-previously used or a 18d-previously CIDR® and 0, 200UI or 300UI of eCG (Folligon®) on D9. In Exp.2, 702 non-lactating Nellore cows were assigned to receive PGF2α treatment either on D7 or D9 and 0 or 300 IU of eCG on D9. On these experiments, the diameter of the largest follicle (ØFD) was measured on D11. Blood samples were collected on D9 and D18 (seven days after TAI) to evaluate serum progesterone concentrations. In Exp.3, 1,332 suckled Nellore cows were evaluated on D7 for luteal tissue presence. Cows were assigned to receive PGF2α either on D7 or D9. Blood samples were collected on D9. Pregnancy diagnosis was performed on D41. Continuous variables were evaluated by PROC GLM and binary by PROC LOGISTIC. Significant differences were considered when P<0.05 and tendencies when P<0.1. In Exp.1, heifers treated with non-previously used CIDR® had greater [P4D9] (3.06±0.09 vs. 2.53±0.09 ng/ml). The [P4D9] negatively affected the ØFD. There was effect of eCG dosage on ØFD (0IU: 11.5±0.1a; 200IU: 11.9±0.1b; 300IU: 12.0±0.1bmm). The ØFD positively affected the [P4D18]. The eCG dosage influenced the [P4D18] (0UI: 2.77±0.11a; 200UI: 3.18±0.11b; 300UI: 4.87±0.11cng/ml). Treatment with eCG affected synchronization rate [SR; 0IU: 83.8% (337/402)a; 200IU: 88.5% (339/383)ab; 300IU: 94.3% (347/368)b]. The [P4D9] tended to negatively affect, and the ØFD positively affected the SR. There was interaction between eCG and [P4D9] on conception...
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Efeitos da administração peridural de neostigmina associada ou não a clonidina sobre a concentração alveolar mínima do isoflurano em cães /Sisto, Renata Kerche Alvaides. January 2010 (has links)
Orientador: Francisco José Teixeira Neto / Banca: Eduardo Raposo Monteiro / Banca: Silvia Renata Gaido Cortopassi / Resumo: Os agentes anticolinesterásicos (neostigmina), quando associados com agonistas de receptores alfa-2 adrenérgicos (clonidina) pela via espinhal, resultam sinergismo no que se refere à analgesia promovida em ratos, ovinos e humanos. Na presente pesquisa, formulou-se a hipótese de que a administração peridural de neostigmina potencializaria a redução da concentração alveolar mínima (CAM) do isoflurano proporcionada pela clonidina peridural em cães. Seis cadelas hígidas (14,9 ± 2,9 kg) foram anestesiadas com isoflurano em 3 ocasiões distintas, com intervalo de 7 dias. Durante as anestesias foi empregada a ventilação controlada a pressão para prevenção da hipercapnia (PaCO2 > 45 mmHg) e a temperatura esofágica foi mantida entre 37,5 a 38,5oC por meios de aquecimento artificiais. Em cada anestesia, os animais receberam aleatoriamente 1 de 3 tratamentos pela via peridural: neostigmina (10 μg/kg), clonidina (20 μg/kg), ou a associação clonidina (20 μg/kg) e neostigmina (10 μg/kg). A CAM do isoflurano, mensurada por meio de estimulação nociceptiva do membro pélvico (50 V, 50 Hz, 10 ms), foi registrada após 2 horas da indução da anestesia (CAM basal) e após 2,5 e 5 horas da administração dos tratamentos peridurais. Em um dos animais, tanto a clonidina como a clonidina/neostigmina resultou em elevação paradoxal da CAM (8-9 %). Nos demais animais estudados (n = 5), os valores de CAM basal (média ± desvio padrão) foram de 1,49 ± 0,26, 1,51 ± 0,23 e 1,49 ± 0,26 vol%, nos tratamentos clonidina, neostigmina e clonidina/neostigmina, respectivamente, não havendo diferença entre tratamentos. As reduções da CAM observadas após a administração peridural de neostigmina não foram significativas (p < 0,05) (reduções percentuais de 11 ± 5% e 8 ± 9% após 2,5 e 5 horas, respectivamente). Houve redução significativa da CAM após a administração peridural de ... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: Spinal administration of anticholinesterase drugs (neostigmine) in combination with alpha-2 adrenergic receptor agonists (clonidine) results in a synergistic analgesic effect in rats, sheep and humans. The hypothesis of the present study was that the epidural administration of neostigmine would enhance the isoflurane minimum alveolar concentration (MAC) reduction induced by the epidural injection of clonidine in dogs. Six healthy bitches (14,9 ± 2,0 kg ) were anesthetized with isoflurane on 3 distinct occasions, with 7 day intervals among experiments. During the anesthetic episodes, animals were maintained under pressure controlled ventilation to prevent hypercapnia (PaCO2 > 45 mmHg) and esophageal temperature was maintained between 37.5 and 38.5 oC by means of artificial heating devices. During each anesthetic, animals were randomly allocated to receive 1 of 3 epidural treatments: neostigmine (10 μg/kg), clonidine (20 μg/kg), or the combination of clonidine (20 μg/kg) and neostigmine (10 μg/kg). Isoflurane MAC, determined by means of electric stimulation of the pelvic limb (50 V, 50 Hz, 10 ms), was recorded 2 hours after induction of anesthesia (baseline MAC) and 2.5 and 5 hours after epidural injections. In 1 of the animals, clonidine and clonidine/neostigmine caused paradoxical increases in MAC (8-9 % increases). For the remaining animals (n = 5), baseline MAC values (mean ± standard deviation) were 1.49 ± 0.26, 1.51 ± 0.23 e 1.49 ± 0.26 vol%, in the clonidine, neostigmine, and clonidine/neostigmine treatments, respectively. Baseline MAC did not differ among treatments. The isoflurane MAC reductions recorded after epidural injection of neostigmine were not significant (p < 0.05) (percent reductions of 11 ± 5% and 8 ± 9% after 2.5 and 5 hours respectively). The MAC reductions observed after epidural injection of clonidine (35 ± 9% and 22 ± 14% after 2.5 and 5 hours, ... (Complete abstract click electronic access below) / Mestre
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Composição bioquímica e hormonal do líquido ammniotico de fetos bovinos oriundos de inseminação artificial(IA), transferência de embriões(TE) e produção in vitro(PIV) /Piagentini, Marcelo. January 2008 (has links)
Orientador: Nereu Carlos Prestes / Banca: Eunice Oba / Banca: Regina Kiomi Takahira / Banca: Daniel Bartceli de Souza / Banca: Gilson Hélio Toniollo / Resumo: O presente trabalho teve por objetivo comparar a composição bioquímica e as concentrações de testosterona e progesterona no líquido amniótico de fetos bovino da raça Nelore produzidos por fecundação in vivo, fecundação in vivo com transferência de embrião (TE) e produção in vitro (PIV). Os problemas fetais observados ao momento do parto e pós-parto imediato em animais oriundos de PIV e a escassez de pesquisas que determinem a composição do líquido amniótico associada aos três sistemas de produção embrionária permitiram o desenvolvimento deste trabalho. Utilizaram-se 60 animais divididos em: grupo 01 - vacas Nelore gestando bezerros oriundos de inseminação artificial (IA) (n=20); grupo 02 - receptoras gestando bezerros Nelore provenientes de inovulações de embriões oriundos de doadoras superovuladas pelo método convencional (n=20); grupo 03 - receptoras de embriões gestando bezerros Nelore originados de inovulações de embriões oriundos de doadoras pelo método de aspiração folicular (n=20). No momento do parto, após a visualização das bolsas, colheram-se 15mL de líquido amniótico por punção da bolsa com agulha e seringa adequadas. As amostras foram processadas e analisadas no serviço de laboratório clínico do Departamento de Clínica Veterinária da FMVZ/UNESP de Botucatu-SP e no Laboratório de Endocrinologia do departamento de Reprodução Animal e Radiologia Veterinária. Para análise bioquímica foram utilizados Kits comerciais seguindo a técnica recomendada pelo fabricante. A dosagem hormonal de progesterona (P4) e testosterona (T) foi determinada por meio de radioimunoensaio em fase sólida com a leitura realizada em contador Gama Count Cobra II. Os dados obtidos na avaliação bioquímica e no perfil hormonal foram submetidos à análise de variância (ANOVA) e, uma vez demonstrada diferença estatística por 22 esse teste aplicou-se o Método de Tukey, com 5% de nível de significância. / Abstract: The present work had for objective to compare the biochemical composition and the concentrations of testosterone and progesterone in the amniotic fluid of fetuses of the Nelore cows produced by in vivo fecundation, in vivo fecundation at embryo transfer (ET) and in vitro production (IVP). The fetal problems observed at the delivery moment and at the immediate post-partum in animals originating from IVP and the shortage of researches that determine the composition of the amniotic fluid associated to the three systems of embryonic production allowed the development of this work, adding results to the studies that are being done by other researchers with the placenta of IVP animals. Sixty animals were used divided into 3 groups: Group 1 - Nelore cows pregnant with calves conceived by artificial insemination (AI) (n=20); Group 2 - receptor cows pregnant with Nelore calves provement from superovulation of embryo donors (n=20); Group 3 - receptor cows pregnant with Nelore calves obtained by in vitro production after follicular aspiration (n=20). At the delivery moment, after the visualization of the sacs, 15mL of amniotic liquid were collected by puncture. The samples were processed and analyzed in the service of clinical laboratory of the Department of Veterinary Clinic of FMVZ/UNESP of Botucatu-SP and in the Laboratory of Endocrinology of the department of Animal Reproduction and Veterinary Radiology. For biochemical analysis commercial kits were used following the technique recommended by the manufacturer. The hormonal determinaton of progesterone (P4) and testosterone (T) was performed through radioimmunossay (RIA) in solid phase with the reading accomplished in accountant Gama Count Collects II. The data obtained in the biochemical evaluation and in the hormonal profile were submitted to the variance analysis (ANOVA) and, once demonstrated a statistic difference by that method the Tukey test was applied, with a 24 5% of level significancy. / Doutor
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Nitrite oxidising bacteria in soil : examination of the interactions with ammonia oxidisers and the influence of pH on their diversity and distributionMeng, Yiyu January 2016 (has links)
Nitrification is a central part of the nitrogen cycle, whereby the most reduced form, ammonia, is converted to the most oxidised form, nitrate via nitrite. The first step is performed by ammonia oxidising bacteria (AOB) and archaea (AOA), with the second step performed by nitrite oxidising bacteria (NOB). Although both groups are closely associated in nature, ammonia oxidisers have received more attention compared to NOB as ammonia oxidation is considered the rate-limiting step. Nitrobacter and Nitrospira are two important groups of soil NOB. To determine whether there are specific associations of AOA or AOB with certain NOB, the effect of organic and inorganic ammonia sources was tested by adding glutamate or ammonium sulphate to soil together with either 5% 12CO2 or 13CO2 to determined autotrophic growth by DNA-SIP. The results demonstrated that while the various ammonia and nitrite oxidisers responded differently, there was no direct evidence of specific coupled interactions. The effects of soil pH on Nitrobacter and Nitrospira was then investigated in a long-term pH gradient in an agricultural field. The results demonstrated that Nitrospira abundance was lower in acidic soils, whereas Nitrobacter abundance remained equally or more abundant. pH also influenced the relative distribution of Nitrobacter and Nitrospira populations, with distinct community structures at both high and low pH. The interaction of AOA and NOB was further investigated in a co-culture experiment, and demonstrated that the removal of nitrite and free nitrous acid NOB enhanced both rates and amounts of ammonia oxidised, indicating that in acidic environments these relationships may be particularly critical. Finally, the use of the compound PTIO was investigated for potential use in elucidating specific relationships between AOA and NOB. Results demonstrated a lack of specificity for the target group, and was unstable in soil, and therefore its use in soil should proceed with caution.
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