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Seletividade de herbicidas à cultura da mandiocaAbreu, Magno Luiz de [UNESP] 05 February 2010 (has links) (PDF)
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abreu_ml_me_botfca.pdf: 619952 bytes, checksum: dbe831b21285a33d1914adaf5e7b4730 (MD5) / Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) / A recomendação de um herbicida está condicionada a sua seletividade, ou seja, a sua capacidade de eliminar espécies vegetais indesejáveis sem promover reduções economicamente significativas, tanto na qualidade quanto na quantidade produzida pela cultura. A presente pesquisa avaliou a seletividade de herbicidas aplicados em pré e pós-emergência da cultura da mandioca cultivada considerando-se a intensidade de injuria na parte aérea, características morfológicas da planta, componentes da produtividade, produtividade e balanço de massa das raízes feculentas. Os experimentos foram instalados nos municípios de Botucatu/SP, Brasil em solo argiloso e em São Manuel/SP, Brasil em solo arenoso, no ano agrícola de 2008. Foi utilizado o delineamento em blocos ao acaso com quatro repetições, em esquema fatorial 11 X 2, sendo causa de variação dez herbicidas ametryne (1000g ha-1), clomazone (500g ha-1), ametryne + clomazone (750 + 500g ha-1) e atrazine (500g ha-1), aplicados logo após o plantio em pré-emergência da mandioca: haloxyfof-methyl (48 g ha-1), sethoxydim (200 g ha-1), fluazifop-p-butyl (100 g ha-1), quizalofop-p-ethyl (75 g ha-1), fomezafen (225 g ha-1) e bentazon (720 g ha-1), aplicados em pósemergência da cultura, mais uma testemunha capinada e duas variedades IAC14 e IAC576-70. Para a aplicação dos herbicidas foi utilizado um pulverizador costal, pressurizado a CO2 e equipado com barra de aplicação com cinco pontas Teejet XR 110 02vs espaçadas em 0,50m, com consumo de calda de 200 L ha-1. A fitotoxicidade das plantas de mandioca foi avaliada visualmente valendo-se de uma escala percentual de notas, na qual “zero” correspondeu a nenhuma injúria e “cem” a morte das plantas. Antes da colheita foram avaliadas a altura das plantas (cm), altura da primeira... / The herbicide recommendation is subjected to its selectivity and ability to eliminate undesirable species without promoting economically significant reductions in both quality and crop production. Thus, this work aimed to test the selectivity of herbicides applied in pre-and post-emergence of cassava crop considering the intensity of injury in the shoot, components of productivity, productivity end balance of mass of roots starch. The experiments were conducted in Botucatu / SP, Brazil, in a clay soil and São Manuel / SP, Brazil, in sandy soil, in 2008 croprowing season. The treatments was combinated in a 11 X 2 factorial (11 herbicides and 2 varieties) and disposed in a randomized block design. The treatments the herbicides tested was ametryne (1000g ha-1), clomazone (500 g ha-1), ametryne + clomazone (750 + 500 g ha-1 ) and atrazine (500 g ha-1) applied in pre-emergence of cassava,haloxyfof-methyl (48 g ha-1), sethoxydim (200 g ha-1), fluazifop-p-butyl (100 g ha-1), quizalofop-p-ethyl (75 g ha-1), fomezafen (225 g ha-1) and bentazon (720 g ha-1), applied post-emergence of culture as well as an control untreated end two varieties IAC14 and IAC576-70. For the implementation it was used a backpack sprayer, pressurized CO2 and equipped with bar application with five Teejet XR 110 02vs spaced at 0.50 m, with consumption volume of 200 L ha-1 of water. The phytotoxicity of the cassava plants was visually drawing on a percentage scale of notes, where zero corresponds to no injury and 100 % the death of plants. Before harvest were evaluated plant height (cm), height of first branch (cm), stem diameter (cm), final plant stand per hectare, the average number of stems per plant. After harvesting were assessed green mass shoot and the strains (t ha-1), shoots and strains dry... (Complete abstract click electronic access below)
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Optical studies of diatomic molecules at extreme conditionsAfonina, Veronika Semenovna January 2018 (has links)
The formidable progress achieved in the research at extreme conditions led to important discoveries of many unusual and interesting physical and chemical phenomena. Materials with high compressibility were and still are of particular interest due to a significant reduction of volume which could result in unexpected changes of bonding and/or electronic properties. Among highly compressible materials simple diatomic molecules such as H2, N2, and O2 are particularly interesting because they form new types of solids at high pressure. Hydrogen, being the most abundant element in the universe, possesses simple electronic structure, therefore, the study of hydrogen systems is of special interest. In the last three decades, there were subsequently explored and described several high-pressure phases of hydrogen up to 400 GPa. However, there is still a vast area of unexplained effects, which requires further analysis. The contributed work discusses Raman experiments in a wide pressure and temperature range where rotational and lattice phonon excitations have been measured in the Raman spectrum of solid H2 and D2 at 10, 77, 150 and 300 K from 2 to 180 GPa and up to 380 GPa at 300 K. Analysis of the Raman spectra allows to model how the rotational modes change with pressure and temperature and how the mass scaling laws evolve as the density increases in both hydrogen and deuterium. Comparison of vibrational frequencies of the isotopes appears to be extremely useful for estimation of equivalent pressures for both isotopes. Nitrogen and oxygen are archetypal elements possessing unique features such as extremely strong triple bond in case of N2 and magnetic moment in O2 . Both N2 and O2 exhibit rich polymorphism, with additional phases of O2 derived from its electronic and magnetic properties. N2 /O2 mixtures (for example, 20.9% O2 and 78% N2 mixture is air that we breathe) have been studied up to 12 GPa at 300 K experimentally and explored up to 500 GPa at 0 K theoretically. In the current project, N2 /O2 molecular systems are examined at 300 K up to 150 GPa. Rich polymorphism is observed, with seven phases exhibiting drastically different Raman spectra for concentrations below 45% of O2 and a more stable area with three phases in the concentration range from 45% to 80% of oxygen at pressures above 12 GPa. Moreover, characteristic Raman spectra obtained for the mix with 25% O2 after laser heating to approximately 2000 K at 25 and 96 GPa reveals pronounced peaks indicating the potential formation of new compounds.
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Estudo comparativo de contraceptivos orais combinados sobre o sistema complemento e moléculas de adesão solúveis / Comparative study of combined oral contraceptives on the complement system and soluble adhesion moleculesMendonça, Carlos Eduardo Ferareze 03 May 2017 (has links)
A inflamação envolve vários mecanismos biológicos relacionados entre si e altamente regulados: coagulação, fibrinólise, sistema complemento (SC), antioxidação e regulação hormonal. Fisiologicamente, o SC e a coagulação compartilham componentes regulatórios e várias interações entre o SC e a hemostasia têm sido propostas, mas não elucidadas. O interesse científico sobre as interações do SC com a hemostasia é crescente, devido ao risco de tromboembolismo venoso (TEV) associado ao uso de contraceptivos orais combinados (COC). Nosso grupo tem investigado os efeitos de COC sobre o SC, hemostasia e moléculas de adesão. Os resultados confirmam vantagens do etinilestradiol (EE)/levonorgestrel (LNG), um COC de 2ª geração sobre os de 3ª geração, mantendo-o como referência para comparação com novos COC, os quais buscam componentes mais naturais. Os componentes hormonais nos COC podem influenciar as interações entre o endotélio e o SC, as quais medeiam adesão de neutrófilos ao endotélio, podendo favorecer o TEV. Desde o advento dos COC busca-se constantemente minimizar seus efeitos indesejáveis com redução das doses, diferentes combinações de progestógenos/estrógenos e vias de administração. O 17? estradiol (E2) é o estrógeno natural e encontra-se combinado com o progestógeno acetato de nomegestrol (NOMAC), mais seletivo para o receptor de progesterona, minimizando efeitos indesejáveis sobre o metabolismo. Considerando-se os benefícios do EE/LNG e a aprovação do E2/NOMAC, o objetivo deste estudo foi avaliar o efeito destes COC sobre: 1) o SC por ativação das Via Clássica (VC) e Via das Lectinas (VL), concentração de C4d e concentração sérica e atividade do inibidor de C1 (C1inh) e 2) os níveis séricos de moléculas de adesão intercelular (ICAM)-1 e vascular (VCAM)-1 e E-selectina. A atividade hemolítica (AH) sérica da VC foi avaliada por ensaio cinético nos grupos de usuárias ou não dos COC e em pool de soro humano normal (SHN) exposto aos componentes dos COC. Os demais parâmetros (VL, C4d, C1inh e moléculas de adesão) foram avaliados por ensaios imunoenzimáticos. Os resultados foram: 1) não houve diferenças na AH sérica da VC; 2) exceto para EE+LNG, a AH da VC in vitro foi menor quando o pool de SHN foi exposto aos componentes individuais das formulações dos COC (EE, LNG, E2 e NOMAC) e à combinação E2+NOMAC comparada ao controle (pool SHN sem componentes das formulações dos COC), menor para E2+NOMAC comparada ao EE+LNG e menor para o NOMAC comparado ao LNG; 3) não houve diferenças na ativação da VL; 4) não houve diferenças na concentração sérica do fragmento C4d; 5) a concentração sérica do C1inh foi maior para o grupo EE/LNG, enquanto a atividade do mesmo foi maior para o grupo E2/NOMAC quando comparadas ao grupo controle; 6) a concentração sérica de E-selectina foi maior para o grupo E2/NOMAC comparada ao grupo controle e 7) não houve diferenças para ICAM-1 e VCAM-1. E2/NOMAC teve efeito sobre maior número de parâmetros comparados ao grupo controle, significativos para a maior atividade do C1inh e maior concentração de E-selectina. Este é o primeiro resultado, ao nosso conhecimento, sobre a relação do NOMAC e E-selectina. Observaram-se tendências para redução da AH da VC em consonância com a redução do C4d. Esta observação deve ser destacada uma vez que E2+NOMAC e seus componentes individualizados promoveram redução significativa na AH in vitro do SHN. Juntos estes dados sugerem ao E2/NOMAC um efeito sobre a regulação negativa da atividade do SC, enquanto o aumento de E-selectina sugere um efeito pró-inflamatório. Quanto ao EE/LNG, a maioria dos parâmetros manteve-se sem diferenças em relação ao grupo controle. O impacto destas observações depende de aprofundamento na investigação dos efeitos dos COC sobre os sistemas biológicos e de estudos clínicos controlados, os quais juntos podem refletir benefícios em muitos aspectos para a saúde humana, em particular, a contracepção e terapias de reposição hormonal / Inflammation involves several biologically related and highly regulated biological mechanisms: coagulation, fibrinolysis, complement system (CS), antioxidation and hormonal regulation. Physiologically, CS and coagulation share regulatory components and various interactions between CS and hemostasis have been proposed but not elucidated. The scientific interest in CS interactions with hemostasis is increasing because of the risk of venous thromboembolism (VTE) associated with combined oral contraceptive (COC) use. Our group has investigated the effects of COC on CS, hemostasis and adhesion molecules. Results confirm the advantages of ethinylestradiol (EE)/levonorgestrel (LNG), a 2nd generation COC over the 3rd generation, maintaining it as a reference for comparison with new COC, which seek more natural components. Hormonal components in COC can influence the interactions between the endothelium and the CS, which mediates neutrophil adhesion to the endothelium and may favor VTE. Since the advent of COC, it has been consistently sought to minimize its undesirable effects by reducing dosages, different combinations of progestogens/estrogens and routes of administration. E2 or 17? estradiol is the natural estrogen and is combined with a new progestin, the nomegestrol acetate (NOMAC), which is more selective for the progesterone receptor, minimizing undesirable effects on metabolism. Considering the benefits of EE/LNG and the approval of E2/NOMAC, the objective of this study was to evaluate the effect of these COC on: 1) CS by measurement of activation of Classical Pathway (CP) and Lectin Pathway (LP), serum concentration of C4d fragment, serum concentration and activity of C1 inhibitor (C1inh) and 2) serum levels of soluble adhesion molecules: intercellular adhesion molecule (ICAM)-1, vascular cell adhesion molecule (VCAM)-1 and E-selectin. The serum hemolytic activity (HA) of CP was assessed by kinetic assay in the COC and non-COC users and in normal human serum (NHS) groups exposed to COC components. Other parameters (LP, C4d, C1inh and soluble adhesion molecules) were evaluated by immunoenzymatic assays. The results were: 1) there was no difference in serum HA of CP; 2) except for EE + LNG, the HA of CP in vitro was lower when the pool of NHS was exposed to the individual components of the COC formulations (EE, LNG, E2 and NOMAC) and the E2+NOMAC combination compared to the control group (pool of NHS without hormonal components), lower for E2+NOMAC compared to EE+LNG and lower for NOMAC compared to LNG; 3) there was no difference in the activation of the LP; 4) there was no difference in the serum concentration of the C4d fragment; 5) the serum concentration of the C1inh was higher for EE/LNG group, whereas its activity was higher for E2/NOMAC group when compared to the control group; 6) the serum concentration of E-selectin was higher for E2/NOMAC group compared to the control group and 7) there was no difference for ICAM-1 and VCAM-1. E2/NOMAC had an effect on a higher number of parameters compared to control group, significant for the higher activity of C1inh and higher concentration of E-selectin. This is the first result, to our knowledge, about the association of NOMAC wiht E-selectin. Tendencies to reduce the HA of the CP were observed in consonance with the reduction of C4d. This observation should be highlighted since E2+NOMAC and its individualized components promoted a significant reduction in the HA in vitro of NHS. Together these data suggest to E2/NOMAC an effect on the down-regulation of CS activity, while the increase of soluble E-selectin suggests a pro-inflammatory effect. Regarding EE/LNG, most of the parameters have no difference compared to control group. The impact of these observations depends on further research into the effects of COC on biological systems and on controlled clinical studies, which together may reflect benefits in many respects to human health, in particular contraception and hormone replacement therapies
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Small molecule stimulators for enhanced yield of human hematopoietic stem cells / Petites molecules stimulatrices pour un rendement accru en cellules souches hématopoietiques humainesNgom, Mor 27 September 2017 (has links)
Une transduction efficace des cellules souches hematopoïetiques est un préalable pour la thérapie génique des maladies génétiques comme la β‐thalassemie, l’Adrenoleucodystrophie et le Déficit Immunitaire Combiné Sévère. La petite molécule UM171 à été décrite comme étant une molécule capable de stimuler l’expansion in vitro des cellules souches hématopoïétiques humaines, permettant ainsi une plus large application des thérapies basées sur les cellules souches. Nous avons aussi conduit des études supplémetaires pour confirmer la capacité de UM171 à expandre les souches hématopoïétiques. Durant ce travail, nous avons découvert que UM171 pouvait aussi augmenter de maniére significative, l’efficience de la transduction lentivirale des cellules hématopoïetiques primitives dérivées de sang de cordon. En plus, nous avons montré que UM171 augmentait la transduction des cellules hématopoïeques ayant les phénotypes les plus immatures. Des études plus approfondies ont aussi révélé que UM171 pouvait aussi augmenter la transduction des cellules souches hématopoïétiques avec des lentivirus ayant diffèrent pseudotypes. Au total ces découvertes ont pour conséquence, une nette amélioration des protocoles d’expansion et de transduction des cellules souches hématopoïétiques à travers un meilleur rendement en cellules souches et des taux élevés de transfert de gène en utilisant des quantités réduites de particules virales / Efficient lentiviral gene transfer to hematopoietic stem cells is a prerequisite for theultimate goal of gene therapy for a range of major genetic diseases such as β‐thalassemia, Adrenoleucodystrophy and severe combined immnodeficiency. The small molecule UM171 was recently described as having potent ability to stimulate ex vivo expansion of human hematopoietic stem cells, another key to safer and wider application of stem cell mediated therapies. Here we have conducted additional studies to confirm the stem cell expansion properties of UM171 and in the course of this work discovered that it also has the ability to significantly enhance the efficiency of the lentiviral transduction of primitive hematopietic cells in human cord blood. Subsequent work confirmed that this enhancing effect extends importantly to the most primitive hematopoietic subset as assessed phenotypically and by functional readout in immunodeficient mouse xenografts. Further detailed characterization ofthis phenomenom revealed that UM171’s effects are manifest rapidly and extend to a range of lentiviral pseudotypes. Together these findingsprovide an avenue for improved protocols for hematopoietic stem cell transduction that achieve higher gene efficiency and stem cell recovery coupled with the potential for reduced viral titer requirements.
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Méthodes de dynamique quantique ultrarapide basées sur la propagation de trajectoires / Trajectory-based methods for the study of ultrafast quantum dynamicsCruz Rodriguez, Lidice 11 December 2018 (has links)
Dans cette thèse, différentes méthodes de dynamique quantique basées sur la propagation de trajectoires sont développées. La première approche consiste en une développer global des champs hydrodynamiques sur une base de polynômes de Chebyshev. Ce schéma est utilisé pour étudier la dynamique vibrationnelle unidimensionnelle de paquets d'ondes dans des potentiels harmoniques et anharmoniques. Par la suite, une méthodologie différente est développée, qui, à partir d'un paramétrage précédemment proposé pour la densité quantique, permet de construire des potentiels d'interaction effectifs entre les pseudo-particules représentant la densité. Dans le cadre de cette approche, plusieurs problèmes de modélisation sont étudiés et des effets quantiques importants sont décrits, tels que l'énergie de point zéro, l'effet tunnel, la diffusion et la réflexion sur une barrière. La même approximation est utilisée pour l'étude de l'ionisation des atomes par laser. Dans une troisième approche, un potentiel quantique approximatif à plusieurs corps est dérivé pour décrire des matrices d'argon et de krypton contenant une impureté de sodium. Il est obtenu en proposant un ansatz approprié pour la fonction d'onde de l'état fondamental du solide. Le potentiel est utilisé dans les simulations de dynamique moléculaire pour obtenir les spectres d'absorption de l'atome de Na isolé dans les matrices cryogéniques. / In this thesis different trajectory-based methods for the study of quantum mechanical phenomena are developed. The first approach is based on a global expansion of the hydrodynamic fields in Chebyshev polynomials. The scheme is used for the study of one-dimensional vibrational dynamics of bound wave packets in harmonic and anharmonic potentials. Furthermore, a different methodology is developed, which, starting from a parametrization previously proposed for the density, allows the construction of effective interaction potentials between the pseudo-particles representing the density. Within this approach several model problems are studied and important quantum mechanical effects such as, zero point energy, tunneling, barrier scattering and over barrier reflection are founded to be correctly described by the ensemble of interacting trajectories. The same approximation is used for study the laser-driven atom ionization. A third approach considered in this work consists in the derivation of an approximate many-body quantum potential for cryogenic Ar and Kr matrices with an embedded Na impurity. To this end, a suitable ansatz for the ground state wave function of the solid is proposed. This allows to construct an approximate quantum potential which is employed in molecular dynamics simulations to obtain the absorption spectra of the Na impurity isolated in the rare gas matrix.
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Exploring the binding of small guest molecules in sodium deoxycholate hydrogelsSeyedalikhani, Mehraveh 03 November 2016 (has links)
Bile salts are supramolecules with amphiphilic properties. Bile salts form aggregates in aqueous solutions. The primary aggregates of bile salts are hydrophobic and the secondary aggregates which form at higher concentrations are relatively hydrophilic. Among bile salts, sodium deoxycholate (NaDC) has been known to form hydrogels at pHs close to the neutral pH and within a certain concentration range.
The aim of this work was to provide insight into the properties of a NaDC hydrogel as a supramolecular gel system through three different projects. Pyrene is a hydrophobic polycyclic aromatic compound which was used as a fluorescent probe and the guest for these projects. 1,1’-dioctadecyl-3,3,3’,3’-tetramethylindodicarbocyanine perchlorate (DiD) is another fluorescent compound which was used as another guest.
The objective of the first project was to understand the mobility of a small guest molecule in NaDC gel in the presence of cucurbit[6]uril (CB[6]) compound as an additive for the gel. Cucurbit[n]urils are macrocyclic compounds with a hydrophobic cavity and two hydrophilic portals. The presence of CB[6] provides another binding site for pyrene in addition to the primary aggregates of the bile salts. The results showed that the mobility of the guest from water and CB[6] to the bile salts network happens when the temperature is raised. The release of the guest back into the water happens when the gel is cooled.
The objective of the second project was to investigate the effect of surfaces with different hydrophilicity on the NaDC gel properties. The results of fluorescence correlation spectroscopy (FCS) experiments revealed that either the hydrophilicity of the surface does not affect the NaDC gel network or the FCS is insensitive to the structural changes induced by the hydrophilicity of the surface. These experiments depicted that the aggregates involved in the gel’s network are the same as those formed in the aqueous solutions. Moreover, results of the steady-state and time-resolved fluorescence experiments showed that the bulk gel properties are not affected by the hydrophilicity of the surface.
The objective of the last project was to determine the effect of ions on NaDC gel properties. The results showed that cations with different charge density have different effects on the gel formation and properties. The presence of inorganic salts with a monovalent cation leads to the formation of a kinetically favored gel sample within a few hours after sample preparation. The extension of the network occurs overtime and a thermodynamically stable gel forms a couple of days after sample preparation. / Graduate / 2020-10-20
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Regulation of adhesion between round spermatids and Sertoli cells in the testisPearce, Kristen (Kristen Joanne), 1974- January 2003 (has links)
Abstract not available
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Some unusual, astronomically significant organic moleculesPeppe, Salvatore. January 2002 (has links) (PDF)
Appendix inside back cover. "June 2002" Bibliography: leaves 157-168. Experimental and theoretical studies were carried out on a number of unusual organic molecules of potential astronomical significance. The experimental work was corroborated by various theoretical approaches and by utilising computer-based quantum chemical calculations. Various covalently bound, anionic and neutral oxocarbon species were formed and studied. Additionally, two analogous heterocumulenic systems were investigated. Some isomers of either system, when energised, were shown to undergo gas-phase rearrangement processes.
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Some unusual, astronomically significant organic molecules / by Salvatore Peppe.Peppe, Salvatore January 2002 (has links)
Appendix inside back cover. / "June 2002" / Bibliography: leaves 157-168. / x, 168, [19] leaves : ill. ; 30 cm. / Title page, contents and abstract only. The complete thesis in print form is available from the University Library. / Experimental and theoretical studies were carried out on a number of unusual organic molecules of potential astronomical significance. The experimental work was corroborated by various theoretical approaches and by utilising computer-based quantum chemical calculations. Various covalently bound, anionic and neutral oxocarbon species were formed and studied. Additionally, two analogous heterocumulenic systems were investigated. Some isomers of either system, when energised, were shown to undergo gas-phase rearrangement processes. / Thesis (Ph.D.)--University of Adelaide, Dept. of Chemistry, 2002
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Studies into selected organic anions and cumulenic systems of interstellar significance / by Andrew Michael McAnoy.Mc Anoy, Andrew Michael January 2003 (has links)
"February 2003" / Bibliography: leaves 186-201. / viii, 201, ix, [41] leaves : ill. ; 30 cm. / Title page, contents and abstract only. The complete thesis in print form is available from the University Library. / Thesis (Ph.D.)--University of Adelaide, Dept. of Chemistry, 2003
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