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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.
1

Desenvolvimento de um sistema automatizado baseado na adoção de Dispositivo Móvel para auxiliar o automanejo da asma em adultos

Silva, Thales Araújo da, 92-98107-4343 17 April 2018 (has links)
Submitted by Divisão de Documentação/BC Biblioteca Central (ddbc@ufam.edu.br) on 2018-09-11T13:36:33Z No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) dissertacao_thales.pdf: 2659033 bytes, checksum: 9a96dedd0f0c9e593202e4c93a2b0b17 (MD5) / Made available in DSpace on 2018-09-11T13:36:33Z (GMT). No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) dissertacao_thales.pdf: 2659033 bytes, checksum: 9a96dedd0f0c9e593202e4c93a2b0b17 (MD5) Previous issue date: 2018-04-17 / Asthma is a chronic disease associated with airway hyperresponsiveness and variable airflow obstruction, with symptoms such as shortness of breath, chest tightness and coughing. The World Health Organization estimates that there are 235 million asthmatics in the world. One of the major difficulties in treatment is to establish the level of asthma control. Lack of knowledge of the level of control itself may adversely affect treatment. International and national guidelines point to self-management as the best way to follow up asthma treatment and measure the level of control. To perform this self-management, patients should complete a questionnaire about the history of their symptoms and perform a peak expiratory flow test, determining the level of control. One of the questionnaires used is the Asthma Control Questionnaire (ACQ). However, using current techniques using a written questionnaire reduces the interest to measure the level control and adherence to treatment. This work proposes a system based on the adoption of mobile device to promote tools with the objective of assisting the self-management of asthma. The system consists of an application on the Android® platform in which the patient can fill the ACQ questionnaire, a WEB platform for the physician to follow data generated by patients and Firebase® services to manage the services online. In a preliminary test, 22 people used the application for 4 weeks. A survey of 9 people in this group pointed out that 89% would use the system regularly. The proposed system may contribute positively to the treatment of asthma by providing tools to aid self-management. / A asma é uma doença crônica associada à hiperresponsividade das vias aéreas e obstrução variável do fluxo aéreo, tendo como principais sintomas a falta de ar, aperto no peito e tosse. A Organização Mundial de Saúde estima que existam 235 milhões de asmáticos no mundo. Uma das principais dificuldades no tratamento é estabelecer o nível de controle da asma. A falta de conhecimento do próprio nível de controle pode influir negativamente no tratamento. As diretrizes internacional e nacional apontam o automanejo como a melhor forma de tratamento de rotina da asma e determinação do nível de controle. Para realizar este automanejo, os pacientes devem preencher um questionário sobre o histórico dos seus sintomas e realizar um teste de pico de fluxo expiratório e a partir destes determinar seu nível de controle regularmente. Um dos questionários utilizado é o Asthma Control Questionnaire (ACQ). No entanto, o uso de técnicas atuais utilizando um questionário por escrito reduz o interesse pela avaliação do controle com impacto na aderência ao tratamento. Este trabalho propõe um sistema baseado na adoção de dispositivo móvel para promover ferramentas com o objetivo de auxiliar o automanejo da asma. O sistema é constituído de um aplicativo em plataforma Android®, na qual o paciente pode preencher o questionário ACQ, uma plataforma WEB para que o médico acompanhe os dados gerados pelo paciente e serviços do Firebase® para gerenciar os serviços online. Em um teste preliminar, 22 pessoas utilizaram o aplicativo durante 4 semanas. Uma pesquisa realizada com 9 pessoas deste grupo, apontou que 89% utilizariam o sistema regularmente. O sistema proposto pode vir a contribuir positivamente no tratamento da asma fornecendo ferramentas para auxiliar o automanejo.
2

Efeitos clínicos, funcionais e em citocinas circulantes da redução do peso em pacientes asmáticos obesos / Clinical, functional and cytokines effects of weight reduction in patients obese asthmatics

Dias Júnior, Sérvulo Azevedo 10 December 2012 (has links)
INTRODUÇÃO: A asma grave acomete menos de 10% dos asmáticos, mas tem um impacto desproporcional sobre a utilização de recursos de saúde, contribuindo para, pelo menos, metade dos custos diretos e indiretos da doença. A proporção de indivíduos obesos ou com sobrepeso é elevada em pacientes com asma grave. Na verdade, a obesidade é um fator de risco para a asma, está associada com a gravidade da doença, com pior resposta a corticosteroides e pior controle clínico. Estudos sobre os efeitos da perda de peso em pacientes com asma ainda são escassos. OBJETIVOS: Avaliar o impacto da perda de peso com medidas clínicas em pacientes com asma grave e obesidade. MÉTODOS: Este é um estudo prospectivo randomizado aberto com dois grupos paralelos. Os participantes eram obesos e com asma grave e que, depois de um período de run-in de três meses, não estavam controlados de acordo com critérios da GINA. Os pacientes elegíveis foram randomizados em uma proporção de 2:1 (perda de peso: controle). Todos os participantes passaram por consultas bimensais no ambulatório de asma e foram acompanhados por seis meses. O desfecho primário foi o nível de controle da asma seis meses após o início do programa de redução de peso medido pelo Questionário de Controle da Asma (ACQ). Os desfechos secundários incluíram o Teste de Controle da Asma (ACT), resultados de função pulmonar, o Questionário Respiratório de St. George (SGRQ), a mudança na reatividade brônquica à metacolina, o uso diário de medicação de alívio para asma, percentagem de dias livres de sintomas, número de visitas ao pronto-socorro e exacerbações, marcadores de inflamação das vias aéreas medidos pelo escarro induzido e pelo óxido nítrico exalado (FeNO). IgE, proteína C reactiva, eotaxina, leptina e Transforming Growth Factor beta 1 (TGF 1) também foram medidos. RESULTADOS: Trinta e três foram randomizados. O grupo era composto predominantemente de mulheres com obstrução moderada, aprisionamento de ar, aumento da resistência das vias aéreas e marcada eosinofilia no escarro. O aumento dos níveis séricos de IgE foram consistentes com uma predominância de asma atópica. Dos 22 pacientes randomizados para submeterem-se a tratamento para a obesidade, 12 atingiram a meta de perda de peso de, pelo menos, 10% do peso corporal. A redução de peso no grupo de tratamento foi associada com melhor controle da asma medido pelo ACQ, ACT e SGRQ. Houve aumento de dias sem sintomas, menor uso de medicação de resgate e menos visitas ao serviço de emergência durante o período de estudo. Não houve diferença no número de exacerbações. A capacidade vital forçada (CVF) aumentou significativamente no grupo de tratamento e permaneceu inalterada no grupo de controle. As outras medidas da função pulmonar não mostraram diferenças entre os grupos. A hiperreatividade das vias aéreas, níveis de óxido nítrico exalado e celularidade do escarro induzido não se alterou ao longo do estudo. Os níveis de leptina diminuíram em ambos os grupos. Os níveis séricos de IgE, proteína C-reactiva, eotaxina, e TGF-1 não se alteraram. CONCLUSÃO: Nosso estudo adiciona informações à controvérsia sobre o impacto da obesidade e seu tratamento no controle da asma. Nossos resultados sugerem que a redução de peso em pacientes obesos com asma grave melhore os resultados de asma por mecanismos não relacionados com a inflamação das vias aéreas e que o controle da asma pobre em pessoas obesas é, pelo menos em parte, o resultado de fatores relacionados com a obesidade. A abordagem terapêutica para pacientes obesos com dificuldade de tratar a asma deve ser destinada à redução de peso, bem como à intensificação do tratamento anti-inflamatório / INTRODUTION: Severe asthma affects less than 10% of asthmatics, but has a disproportionate impact on the use of health resources, contributing to at least half of the direct and indirect costs of the disease. The proportion of obese or overweight individuals is elevated in patients with severe asthma. In fact, obesity is a risk factor for asthma, is associated with the severity of the disease, a poor response to corticosteroids and worse clinical control. Studies on the effects of weight loss in patients with asthma are still scarce. OBJECTIVES: Assess the impact of weight loss with a medical weight loss program in patients with severe asthma associated with obesity. METHODS: This is a prospective open study with two randomized parallel groups. The participants were obese and with severe asthma and, after a three month run-in period, were not controlled according to GINA criteria. Eligible patients were randomized in a 2:1 ratio (weight loss:control). All participants attended bimonthly consultations in the asthma clinic and were followed for six months. The primary outcome measure was the level of asthma control 6 months after initiation of the weight reduction program quantified by using the Asthma Control Questionnaire (ACQ). Secondary clinical outcomes included the Asthma Control Test (ACT), lung function results, score on the St. Georges Respiratory Questionnaire (SGRQ), change in metacholine reactivity, daily use of asthma reliever medication, percentage of asthma symptom free days, number of visits to emergency room and exacerbations, markers of airway cellular inflammation measured in induced sputum and with exhaled nitric oxide (FeNO). IgE, C reactive protein, leptin, eotaxin and Transforming Growth Factor beta 1 (TGF1) levels in serum were also measured. RESULTS: Thirty-three patients were randomized. The group consisted predominantly of women with moderate airflow obstruction, air trapping, increased airway resistance and marked eosinophilia in the sputum. The increased serum levels of IgE were consistent with a predominance of atopic asthma. Of the 22 patients randomized to undergo treatment for obesity, 12 achieved the weight loss goal of at least 10% of body weight. The reduction in weight in the treatment group was associated with improvement in the control as measured by ACQ, ACT and SGRQ. There was increase of symptom-free days, less use of rescue medication and fewer visits to the emergency room during the study period. There were no differences in the number of exacerbations. The forced vital capacity (FVC) increased significantly in the treatment group and remained unchanged in the control group. The other measures of the pulmonary function showed no differences between groups. The airway hyperresponsiveness, exhaled nitric oxide levels and induced sputum cellularity did not change throughout the study. Leptin levels decreased in both groups. Serum levels of IgE, C-reactive protein, eotaxin, and TGF-1 did not change. CONCLUSION: Our study adds information to the controversy about the impact of obesity and its treatment on asthma control. Our results suggest that weight reduction in obese patients with severe asthma improves asthma outcomes by mechanisms not related to airway inflammation and that poor asthma control in people who are obese is at least in part the result of obesity-related factors. The therapeutic approach for obese patients with difficult-to-treat asthma should therefore be aimed at weight reduction as well as on intensifying antiinflammatory treatment
3

Efeitos clínicos, funcionais e em citocinas circulantes da redução do peso em pacientes asmáticos obesos / Clinical, functional and cytokines effects of weight reduction in patients obese asthmatics

Sérvulo Azevedo Dias Júnior 10 December 2012 (has links)
INTRODUÇÃO: A asma grave acomete menos de 10% dos asmáticos, mas tem um impacto desproporcional sobre a utilização de recursos de saúde, contribuindo para, pelo menos, metade dos custos diretos e indiretos da doença. A proporção de indivíduos obesos ou com sobrepeso é elevada em pacientes com asma grave. Na verdade, a obesidade é um fator de risco para a asma, está associada com a gravidade da doença, com pior resposta a corticosteroides e pior controle clínico. Estudos sobre os efeitos da perda de peso em pacientes com asma ainda são escassos. OBJETIVOS: Avaliar o impacto da perda de peso com medidas clínicas em pacientes com asma grave e obesidade. MÉTODOS: Este é um estudo prospectivo randomizado aberto com dois grupos paralelos. Os participantes eram obesos e com asma grave e que, depois de um período de run-in de três meses, não estavam controlados de acordo com critérios da GINA. Os pacientes elegíveis foram randomizados em uma proporção de 2:1 (perda de peso: controle). Todos os participantes passaram por consultas bimensais no ambulatório de asma e foram acompanhados por seis meses. O desfecho primário foi o nível de controle da asma seis meses após o início do programa de redução de peso medido pelo Questionário de Controle da Asma (ACQ). Os desfechos secundários incluíram o Teste de Controle da Asma (ACT), resultados de função pulmonar, o Questionário Respiratório de St. George (SGRQ), a mudança na reatividade brônquica à metacolina, o uso diário de medicação de alívio para asma, percentagem de dias livres de sintomas, número de visitas ao pronto-socorro e exacerbações, marcadores de inflamação das vias aéreas medidos pelo escarro induzido e pelo óxido nítrico exalado (FeNO). IgE, proteína C reactiva, eotaxina, leptina e Transforming Growth Factor beta 1 (TGF 1) também foram medidos. RESULTADOS: Trinta e três foram randomizados. O grupo era composto predominantemente de mulheres com obstrução moderada, aprisionamento de ar, aumento da resistência das vias aéreas e marcada eosinofilia no escarro. O aumento dos níveis séricos de IgE foram consistentes com uma predominância de asma atópica. Dos 22 pacientes randomizados para submeterem-se a tratamento para a obesidade, 12 atingiram a meta de perda de peso de, pelo menos, 10% do peso corporal. A redução de peso no grupo de tratamento foi associada com melhor controle da asma medido pelo ACQ, ACT e SGRQ. Houve aumento de dias sem sintomas, menor uso de medicação de resgate e menos visitas ao serviço de emergência durante o período de estudo. Não houve diferença no número de exacerbações. A capacidade vital forçada (CVF) aumentou significativamente no grupo de tratamento e permaneceu inalterada no grupo de controle. As outras medidas da função pulmonar não mostraram diferenças entre os grupos. A hiperreatividade das vias aéreas, níveis de óxido nítrico exalado e celularidade do escarro induzido não se alterou ao longo do estudo. Os níveis de leptina diminuíram em ambos os grupos. Os níveis séricos de IgE, proteína C-reactiva, eotaxina, e TGF-1 não se alteraram. CONCLUSÃO: Nosso estudo adiciona informações à controvérsia sobre o impacto da obesidade e seu tratamento no controle da asma. Nossos resultados sugerem que a redução de peso em pacientes obesos com asma grave melhore os resultados de asma por mecanismos não relacionados com a inflamação das vias aéreas e que o controle da asma pobre em pessoas obesas é, pelo menos em parte, o resultado de fatores relacionados com a obesidade. A abordagem terapêutica para pacientes obesos com dificuldade de tratar a asma deve ser destinada à redução de peso, bem como à intensificação do tratamento anti-inflamatório / INTRODUTION: Severe asthma affects less than 10% of asthmatics, but has a disproportionate impact on the use of health resources, contributing to at least half of the direct and indirect costs of the disease. The proportion of obese or overweight individuals is elevated in patients with severe asthma. In fact, obesity is a risk factor for asthma, is associated with the severity of the disease, a poor response to corticosteroids and worse clinical control. Studies on the effects of weight loss in patients with asthma are still scarce. OBJECTIVES: Assess the impact of weight loss with a medical weight loss program in patients with severe asthma associated with obesity. METHODS: This is a prospective open study with two randomized parallel groups. The participants were obese and with severe asthma and, after a three month run-in period, were not controlled according to GINA criteria. Eligible patients were randomized in a 2:1 ratio (weight loss:control). All participants attended bimonthly consultations in the asthma clinic and were followed for six months. The primary outcome measure was the level of asthma control 6 months after initiation of the weight reduction program quantified by using the Asthma Control Questionnaire (ACQ). Secondary clinical outcomes included the Asthma Control Test (ACT), lung function results, score on the St. Georges Respiratory Questionnaire (SGRQ), change in metacholine reactivity, daily use of asthma reliever medication, percentage of asthma symptom free days, number of visits to emergency room and exacerbations, markers of airway cellular inflammation measured in induced sputum and with exhaled nitric oxide (FeNO). IgE, C reactive protein, leptin, eotaxin and Transforming Growth Factor beta 1 (TGF1) levels in serum were also measured. RESULTS: Thirty-three patients were randomized. The group consisted predominantly of women with moderate airflow obstruction, air trapping, increased airway resistance and marked eosinophilia in the sputum. The increased serum levels of IgE were consistent with a predominance of atopic asthma. Of the 22 patients randomized to undergo treatment for obesity, 12 achieved the weight loss goal of at least 10% of body weight. The reduction in weight in the treatment group was associated with improvement in the control as measured by ACQ, ACT and SGRQ. There was increase of symptom-free days, less use of rescue medication and fewer visits to the emergency room during the study period. There were no differences in the number of exacerbations. The forced vital capacity (FVC) increased significantly in the treatment group and remained unchanged in the control group. The other measures of the pulmonary function showed no differences between groups. The airway hyperresponsiveness, exhaled nitric oxide levels and induced sputum cellularity did not change throughout the study. Leptin levels decreased in both groups. Serum levels of IgE, C-reactive protein, eotaxin, and TGF-1 did not change. CONCLUSION: Our study adds information to the controversy about the impact of obesity and its treatment on asthma control. Our results suggest that weight reduction in obese patients with severe asthma improves asthma outcomes by mechanisms not related to airway inflammation and that poor asthma control in people who are obese is at least in part the result of obesity-related factors. The therapeutic approach for obese patients with difficult-to-treat asthma should therefore be aimed at weight reduction as well as on intensifying antiinflammatory treatment
4

Adsorption of Alkaline Copper Quat Components in Wood-mechanisms and Influencing Factors

Lee, Myung Jae 31 August 2011 (has links)
Mechanisms of adsorption of alkaline copper quat (ACQ) components in wood were investigated with emphasis on: copper chemisorption, copper physisorption, and quat adsorption. Various factors were investigated that could affect the adsorption of individual ACQ components in red pine wood. Copper chemisorption in wood was affected by ligand types coordinating with Cu and the stability of the Cu-ligand complexes in solution. For Cu-monoethanolamine (Cu-Mea) system, the prevailing active solvent species at the solution pH, [Cu(Mea)2-H]+ complexes with wood acid sites and loses one Mea molecule through a ligand exchange reaction. The amount of adsorbed Cu was closely related to the cation exchange capacity of wood. An increase in Mea/Cu ratio increased the proportion of the uncharged Cu-Mea complex and resulted in decreased Cu chemisorption in wood. Copper precipitation is also an important Cu fixation mechanisms of Cu-amine treated wood. X-ray diffraction analysis revealed that in vitro precipitated Cu was a mixture of copper carbonates (azurite and malachite) and possibly Cu2O. Higher concentration Cu-amine solutions retarded the Cu precipitation to a lower pH because of higher free amine in the preservative-wood system. The changes in zeta potential of wood in relationship to the quaternary ammonium (alkyldimethylbenzylammonium chloride: ADBAC) adsorption isotherm showed two different adsorption mechanisms for quat in wood: ion exchange reaction at low concentration and additional aggregation form of adsorption by hydrophobic interaction at high concentration. Because of the aggregation effect, when wood was treated with ACQ, high amounts of ADBAC were concentrated near the surface creating a steep gradient with depth. This aggregated ADBAC was easily leached out while the ion exchanged ADBAC had high leaching resistance. Free Mea and Cu of ACQ components appeared to compete with ADBAC for the same bonding sites in wood.
5

Influence of Alkaline Copper Quat (ACQ) Solution Parameters on Copper Complex Distribution and Leaching

Pankras Mettlemary, Sedric 31 August 2011 (has links)
The effects of ACQ solution parameters such as copper to quat ratio, pH and copper to ligand ratio on distribution of copper complexes in solution and insoluble precipitates, and on fixation and leaching of copper in treated wood were evaluated. The distribution of ionic complexes, predicted by equilibrium speciation model (MINTEQA2), was related to laboratory fixation and leaching results at controlled ACQ solution parameters. A decrease in the relative proportion of copper in the ACQ formulation from a copper oxide (CuO) to didecyldimethylammonium carbonate (DDACb) ratio of 2:1 to 1:1 and 1:2 resulted in lower copper retention in the treated samples and substantially decreased the amount of copper leached per unit area. For monoethanolamine (Mea) based ACQ, solution parameters which favour a higher proportion of monovalent cationic complex, which consume one reactive site in wood, and the presence of insoluble carbonate precipitate of copper in wood during preservative treatment resulted in higher leach resistance compared to the neutral copper complex present at higher pH. Ammonia (NH3) based ACQ can fix more copper at high pH as there is no chelated neutral complex as in Mea based ACQ; however divalent copper-NH3 complexes may consume two sites to fix in wood. Addition of NH3 in Mea based ACQ at Cu:Mea:NH3 ratio of 1:4:6 at pH 10.6 significantly reduced copper leaching compared to 1:4:0 (without ammonia) at pH 9 due to increased divalent copper-ammonia complexes and decreased neutral copper amine complex at elevated pH. Ammonia addition with a lower proportion of Mea (1:2.5:4 at pH 10.5-10.7), significantly reduced copper leaching compared to 1:4:0 at pH 9; no reduction was observed for ammonia addition in ACQ with a higher proportion of Mea (1:4:4 at pH 10.45). The lower copper leaching from 1:2.5:4 resulted from the higher amount of divalent copper-NH3 complexes at higher pH without compromising the amount of copper precipitated at lower pH. The higher percent copper leached from tetramethylethylenediamine (Tmed) based ACQ compared to Mea and NH3 based ACQ suggested that highly stable complexes tend to stay in solution and do not result in leach resistant copper in the wood.
6

Adsorption of Alkaline Copper Quat Components in Wood-mechanisms and Influencing Factors

Lee, Myung Jae 31 August 2011 (has links)
Mechanisms of adsorption of alkaline copper quat (ACQ) components in wood were investigated with emphasis on: copper chemisorption, copper physisorption, and quat adsorption. Various factors were investigated that could affect the adsorption of individual ACQ components in red pine wood. Copper chemisorption in wood was affected by ligand types coordinating with Cu and the stability of the Cu-ligand complexes in solution. For Cu-monoethanolamine (Cu-Mea) system, the prevailing active solvent species at the solution pH, [Cu(Mea)2-H]+ complexes with wood acid sites and loses one Mea molecule through a ligand exchange reaction. The amount of adsorbed Cu was closely related to the cation exchange capacity of wood. An increase in Mea/Cu ratio increased the proportion of the uncharged Cu-Mea complex and resulted in decreased Cu chemisorption in wood. Copper precipitation is also an important Cu fixation mechanisms of Cu-amine treated wood. X-ray diffraction analysis revealed that in vitro precipitated Cu was a mixture of copper carbonates (azurite and malachite) and possibly Cu2O. Higher concentration Cu-amine solutions retarded the Cu precipitation to a lower pH because of higher free amine in the preservative-wood system. The changes in zeta potential of wood in relationship to the quaternary ammonium (alkyldimethylbenzylammonium chloride: ADBAC) adsorption isotherm showed two different adsorption mechanisms for quat in wood: ion exchange reaction at low concentration and additional aggregation form of adsorption by hydrophobic interaction at high concentration. Because of the aggregation effect, when wood was treated with ACQ, high amounts of ADBAC were concentrated near the surface creating a steep gradient with depth. This aggregated ADBAC was easily leached out while the ion exchanged ADBAC had high leaching resistance. Free Mea and Cu of ACQ components appeared to compete with ADBAC for the same bonding sites in wood.
7

Influence of Alkaline Copper Quat (ACQ) Solution Parameters on Copper Complex Distribution and Leaching

Pankras Mettlemary, Sedric 31 August 2011 (has links)
The effects of ACQ solution parameters such as copper to quat ratio, pH and copper to ligand ratio on distribution of copper complexes in solution and insoluble precipitates, and on fixation and leaching of copper in treated wood were evaluated. The distribution of ionic complexes, predicted by equilibrium speciation model (MINTEQA2), was related to laboratory fixation and leaching results at controlled ACQ solution parameters. A decrease in the relative proportion of copper in the ACQ formulation from a copper oxide (CuO) to didecyldimethylammonium carbonate (DDACb) ratio of 2:1 to 1:1 and 1:2 resulted in lower copper retention in the treated samples and substantially decreased the amount of copper leached per unit area. For monoethanolamine (Mea) based ACQ, solution parameters which favour a higher proportion of monovalent cationic complex, which consume one reactive site in wood, and the presence of insoluble carbonate precipitate of copper in wood during preservative treatment resulted in higher leach resistance compared to the neutral copper complex present at higher pH. Ammonia (NH3) based ACQ can fix more copper at high pH as there is no chelated neutral complex as in Mea based ACQ; however divalent copper-NH3 complexes may consume two sites to fix in wood. Addition of NH3 in Mea based ACQ at Cu:Mea:NH3 ratio of 1:4:6 at pH 10.6 significantly reduced copper leaching compared to 1:4:0 (without ammonia) at pH 9 due to increased divalent copper-ammonia complexes and decreased neutral copper amine complex at elevated pH. Ammonia addition with a lower proportion of Mea (1:2.5:4 at pH 10.5-10.7), significantly reduced copper leaching compared to 1:4:0 at pH 9; no reduction was observed for ammonia addition in ACQ with a higher proportion of Mea (1:4:4 at pH 10.45). The lower copper leaching from 1:2.5:4 resulted from the higher amount of divalent copper-NH3 complexes at higher pH without compromising the amount of copper precipitated at lower pH. The higher percent copper leached from tetramethylethylenediamine (Tmed) based ACQ compared to Mea and NH3 based ACQ suggested that highly stable complexes tend to stay in solution and do not result in leach resistant copper in the wood.

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