Thesis (Ph. D.)--University of Minnesota, 1926. / Cover title. Vita. "By Vlon N. Morris and L.H. Reyerson." Description based on print version record.

Submitted by Lucas Aparecido Manzani Lisboa null (lisboa@dracena.unesp.br) on 2016-09-08T13:35:58Z No. of bitstreams: 1 Tese_49.pdf: 2120369 bytes, checksum: e53b4314ef0a0e3635eade71ecf77734 (MD5) / Approved for entry into archive by Juliano Benedito Ferreira (julianoferreira@reitoria.unesp.br) on 2016-09-12T19:53:54Z (GMT) No. of bitstreams: 1 lisboa_lam_dr_ilha.pdf: 2120369 bytes, checksum: e53b4314ef0a0e3635eade71ecf77734 (MD5) / Made available in DSpace on 2016-09-12T19:53:54Z (GMT). No. of bitstreams: 1 lisboa_lam_dr_ilha.pdf: 2120369 bytes, checksum: e53b4314ef0a0e3635eade71ecf77734 (MD5) Previous issue date: 2016-08-05 / A cana-de-açúcar, pertencente à Família Poaceae, é uma importante cultura para a indústria sucroenergética brasileira. Os hormônios estão intimamente relacionados à emergência das gemas contidas nos minirrebolos de cana-de-açúcar, por ocasião do plantio dos colmos. Este trabalho teve por objetivo avaliar os efeitos do etefon associado à posição de gemas no colmo de cana-de-açúcar no desenvolvimento inicial da cultura. Em março de 2014, na Usina Rio Vermelho, localizada em Junqueirópolis, Estado de São Paulo, foi escolhido um canavial com cana planta, destinado para mudas com idade aproximada de 11 meses. Foram demarcadas duas áreas com dimensões de 20x20 metros. Em uma das áreas foi aplicado o Etefon. Quinze dias após a aplicação, foram coletados minirrebolos contendo 1 e 2 gemas para compor dois experimentos independentes. Da área onde não foi aplicado o produto, foram retirados minirrebolos para os tratamentos controle e aplicação do Etefon no sulco de plantio em vasos. As gemas foram encaminhadas para a Faculdade de Ciências Agrárias e Tecnológicas da Universidade Estadual Paulista “Júlio de Mesquita Filho” – de Dracena, Estado de São Paulo. Os minirrebolos foram oriundos do ápice, meio e base dos colmos de cana-de-açúcar. Dessa maneira, o delineamento experimental foi em esquema fatorial 3x3, ou seja, posição dos minirrebolos nos colmos de cana-de-açúcar e os modos de aplicações do Etefon. Durante a condução dos experimentos, foram determinadas as seguintes características: índice de velocidade de emergência durante os 30 primeiros dias. Aos 30, 60 e 90 dias após a instalação do experimento, foram determinados: número de folhas; altura de plantas; número de perfilhos; diâmetro de perfilhos; peso da matéria seca de caule e folhas; peso da matéria seca de raiz; peso da matéria seca total; área foliar; índice de clorofila; condutância estomática; e características ultraestruturais foliares de cana-de-açúcar. O uso etefon na planta 15 dias antes do plantio, juntamente com minirrebolos oriundos do ápice dos colmos de cana-de-açúcar, apresentaram os melhores resultados para índice de velocidade de emergência; número de perfilhos; área foliar; peso de matéria seca de caule e folhas e área foliar. O uso do Etefon e posições dos minirrebolos nos colmos de cana-de-açúcar não influenciaram no índice de clorofila e condutância estomática. O uso Etefon na planta 15 dias antes do plantio, juntamente com minirrebolos oriundos do ápice seguido do meio dos colmos de cana-de-açúcar, apresentaram melhores resultados para as características ultraestruturais foliares da cana-de-açúcar. / The sugarcane belonging to the family Poaceae is an important crop for the Brazilian sugarcane industry. The hormones are closely related to the emergence of buds contained in the small stalks of the stem of the sugarcane at planting the culms. This study aimed to evaluate the effects of Ethephon associated to the position of the buds in the culm of the sugarcane in the early development of the crop. In March 2014 in Rio Vermelho plant located in Junqueirópolis, State of São Paulo, it was chosen a sugarcane plantation destined to seed with approximate age of 11 months. There were marked two areas with dimensions of 20x20m. Ethephon was applied in one of the areas. On the 15 days after the applications, small stalks of the stem of the sugarcane were collected containing 1 and 2 buds to compose two independent experiments. From the area where the product was not applied, small stalks of the stem of the sugarcane were removed for treatments: control and aplication of Etephon in the planting furrows in vases. The buds were sent to the University of Agricultural Sciences and Technology of Universidade Estadual Paulista "Júlio de Mesquita Filho" - Dracena, State of Sao Paulo. The small stalks of the stem of the sugarcane were removed from the apex, middle and base of sugarcane culms. Thus the experimental design was a 3x3 factorial scheme, i.e. the position of the small stalks of the stem of the sugarcane and the forms of applying the Etephon. The folllowing characteristics were determined during the execution of the experiments: emergency speed index during the first 30 days. On the 30th, 60th and 90th days after the installation of the experiment were determined: number of leaves; weight of the plant; number of culms; diameter of the culms; weight of the dry matter of the stem and leaves; weight of the dry matter of the root; weight of the total dry matter; leaf area; chlorophyll index; stomatal conductance; ultrastructural characteristics of leaves of the sugarcane. Ethephon used in the plant 15 days before planting with small stalks of the stem of the sugarcane from the apex of the plant showed the best results for emergency speed; number of culms; leaf area; weight of the dry matter of the stem and leaves; and leaf area. Ethephon used and the positions of small stalks in the sugarcane did not influence the chlorophyll content and stomatal conductance. Etephon used on the plant 15 days before the planting, along with small stalks of the apex of the plant followed by the middle ones, showed better results for leaves ultrastructural characteristics of the sugarcane.

Orientador: Edson Lazarini / Resumo: A cana-de-açúcar, pertencente à Família Poaceae, é uma importante cultura para a indústria sucroenergética brasileira. Os hormônios estão intimamente relacionados à emergência das gemas contidas nos minirrebolos de cana-de-açúcar, por ocasião do plantio dos colmos. Este trabalho teve por objetivo avaliar os efeitos do etefon associado à posição de gemas no colmo de cana-de-açúcar no desenvolvimento inicial da cultura. Em março de 2014, na Usina Rio Vermelho, localizada em Junqueirópolis, Estado de São Paulo, foi escolhido um canavial com cana planta, destinado para mudas com idade aproximada de 11 meses. Foram demarcadas duas áreas com dimensões de 20x20 metros. Em uma das áreas foi aplicado o Etefon. Quinze dias após a aplicação, foram coletados minirrebolos contendo 1 e 2 gemas para compor dois experimentos independentes. Da área onde não foi aplicado o produto, foram retirados minirrebolos para os tratamentos controle e aplicação do Etefon no sulco de plantio em vasos. As gemas foram encaminhadas para a Faculdade de Ciências Agrárias e Tecnológicas da Universidade Estadual Paulista “Júlio de Mesquita Filho” – de Dracena, Estado de São Paulo. Os minirrebolos foram oriundos do ápice, meio e base dos colmos de cana-de-açúcar. Dessa maneira, o delineamento experimental foi em esquema fatorial 3x3, ou seja, posição dos minirrebolos nos colmos de cana-de-açúcar e os modos de aplicações do Etefon. Durante a condução dos experimentos, foram determinadas as seguintes característica... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The sugarcane belonging to the family Poaceae is an important crop for the Brazilian sugarcane industry. The hormones are closely related to the emergence of buds contained in the small stalks of the stem of the sugarcane at planting the culms. This study aimed to evaluate the effects of Ethephon associated to the position of the buds in the culm of the sugarcane in the early development of the crop. In March 2014 in Rio Vermelho plant located in Junqueirópolis, State of São Paulo, it was chosen a sugarcane plantation destined to seed with approximate age of 11 months. There were marked two areas with dimensions of 20x20m. Ethephon was applied in one of the areas. On the 15 days after the applications, small stalks of the stem of the sugarcane were collected containing 1 and 2 buds to compose two independent experiments. From the area where the product was not applied, small stalks of the stem of the sugarcane were removed for treatments: control and aplication of Etephon in the planting furrows in vases. The buds were sent to the University of Agricultural Sciences and Technology of Universidade Estadual Paulista "Júlio de Mesquita Filho" - Dracena, State of Sao Paulo. The small stalks of the stem of the sugarcane were removed from the apex, middle and base of sugarcane culms. Thus the experimental design was a 3x3 factorial scheme, i.e. the position of the small stalks of the stem of the sugarcane and the forms of applying the Etephon. The folllowing characteristics were de... (Complete abstract click electronic access below) / Doutor

Seven β-triketimine nickel complexes C1-C7 with composition [L1-7Ni(μ-Br)2NiL1- 7][BArF4]2, where L1 = HC{C(Me)=N(2,4,6-Me3C6H2)}3, L2 = HC{C(Me)=N(2,6- Me2C6H3)}3, L3 = HC{C(Me)=N(2,4-Me2C6H3)}3, L4 = HC{C(Me)=N(2-MeC6H4)}3, L5 = HC{C(Me)=N(2,4,6-Me3C6H2)}2{C(Me)=N(2,6-Me2C6H3)}, L6 = HC{C(Me)=N(2,4,6-Me3C6H2)}{C(Me)=N(2,6-Me2C6H3)}2, and L7 = HC{C(Me)=N(2,4,6-Me3C6H2)}{C(Me)=N(2,6-iPr2C6H3)}2 were synthesized from the interaction of nickel(II) bromide with L1-7 in the presence of NaBArF (BArF = [(3,5- (CF3)2C6H3)4B]−). These complexes were then fully characterized by single-crystal X- ray diffraction (XRD), MALDI-MS and elemental analysis. From XRD results, they were found to be five-coordinated dimeric bromide-bridged species [LNi(μ- Br)2NiL][BArF]2. The geometry at nickel was distorted square pyramidal, with the τ parameter in the range 0.05 to 0.28. In addition, an enamine-diimine nickel complex C8: (L2-NiBr2) was synthesized from triketimine ligand L2 and nickel dibromide in THF, thus lacking the weakly co-ordinating BArF anion. This complex was found to be pseudotetrahedral, where only two of the three imine nitrogen atoms co-ordinated. These two nitrogen atoms and two bromine atoms formed the coordination shell of Ni(II). The six-membered ring [Co-N1-C2-C3-C4-N2] adopted a boat conformation. These complexes (C1-C7) were screened in the polymerization of ethylene monomer using methylaluminoxane (MAO) as cocatalyst in toluene as solvent at 30°C. It was observed that the steric and electronic variations conferred on the complexes by ligands L1-7 had a strong influence on the activity and also on the properties of the produced polyethylene. The catalytic activity decreased in the order C2 > C1 > C6 > C5 > C7 in the range 3229 to 271 kg PE (mol Ni)-1 h-1 for a standard set of conditions (3 bar ethylene, 30 ̊C, Al:Ni 2000), while the catalysts C3 and C4, bearing only a single ortho substituents, were inactive under identical conditions. Those conditions also had strong influences on catalyst activity and polymer properties: Al:Ni ratio in the range 500 to 3000 maximized activity at 2000. For the polymerization temperature in the range 20 to 50 °C, the activity was maximized at 30 °C, while the number of branches increased with temperature while Mn decreased due to increased chain transfer. Increasing the polymerization pressure resulted in fewer branches while the molecular weight increased because of high concentration of ethylene monomer. The effect of the nature of the counterion on polymerization activity and on the polymer properties was investigated when ethylene was polymerized by C8 (N,N-Ni) and C2 (N,N,N-Ni). It was found that polyethylene produced by C8 had significantly greater crystallinity (Tm 59 ̊C, 35 branches per 1000 carbons) than that produced by C2 (Tm 36 ̊C, 53 branches per 1000 carbons). The presence of the weakly nucleophilic counterion (BArF) as in C2, may have facilitated chain walking, resulting in a branched polymer, whereas [MeMAO]- (C8) was a slightly more nucleophilic counterion impeding chain walking. Furthermore, activity was also much greater for C2 than for C8. This is the first report of an anion effect on branching.

M.Sc. / The senescence of climacteric flowers such as carnations is accompanied by an increase in ethylene synthesis during the later stages. This increase in ethylene synthesis is preceded by an increase in the sensitivity of the flowers to ethylene. The increase in ethylene sensitivity is accompanied by a concomitant increase in the levels of short-chain saturated fatty acids (SCSFAs). Treatment of carnation flowers with SCSFA results in an increase in ethylene sensitivity. It appears that these acids act by increasing membrane fluidity, causing slight conformational changes in membrane associated proteins and thereby increasing the ability of the tissue to bind ethylene to its membrane associated receptor molecules. The levels of SCSFAs in senescing carnation petals is controlled by the activity of the enzyme acetyl-coenzyme A carboxylase (ACCase). A decrease in the activity of this enzyme results in an increase in the levels of the SCSFAs and vice versa. During the senescence of carnation flowers, ACCase activity fluctuated from day to day. This fluctuation can be correlated to the fluctuations in the ethylene sensitivity of the flowers on a daily basis. In carnation petals, ACCase is located mainly in the plastids. ACCase activity could be controlled via feedback inhibition by long-chain fatty acids such as oleic acid. Treatment of carnation flowers with oleic acid resulted in a concomitant inhibition of ACCase activity, an increase in SCSFA-levels and an increase in ethylene sensitivity. Oleic acid is a competitive inhibitor of ACCase activity, and changes in the levels of oleic acid will affect the activity of the enzyme. An increase in oleic acid concentration resulted in a decrease in enzyme activity. However, in carnations it appears that ACCase activity is not controlled via feedback inhibition by long chain saturated fatty acids. The results of this study clearly show that ACCase activity is controlled directly by the expression of at least the biotinylated (BCCP) subunit of the enzyme. A decrease in the expression of the gene during the early stages of senescence coincided with a decrease in ACCase activity and was accompanied by a concomitant increase in ethylene sensitivity. These results indicate that the increase in ethylene sensitivity caused by an increase in SCSFA levels is directly controlled by the expression of the ACCase genes.

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