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An increase in 2,4-D use is expected as tolerant crops have been approved to use in Brazil, which may negatively affect important crops such as tobacco. Our objective was to determine safe distances between 2,4-D applications and tobacco fields considering herbicide contamination to the harvested product. A field experiment was conducted, consisting of a 2,4-D application done perpendicularly to the wind direction, using a tractor sprayer. Drifted herbicide was collected using tobacco plants placed at various points (-50 up to 400 meters from application zone), following three schemes: a) 0 to 0.5 hours after application (HAT); b) 0 to 24 HAT; and c) 0.5 to 24 HAT. Environmental conditions were recorded. Herbicide in tobacco leaves was quantified. Drift was detected up to 200 m in both years. Vapor movement of 2,4-D was detected up to 400 m from the application strip in 2016, on plants taken to the field after herbicide application. Environmental conditions in 2015 favored off-target movement (higher wind speed and air temperature and lower humidity); although, in 2016 the herbicide traveled further due to wet deposition. These results indicated that a 100-meter buffer zone is enough to significantly decrease chances of tobacco contamination above the tolerated threshold, and highlighted the importance of environmental conditions in the transport processes for 2,4-D under field conditions.

Field experiments were conducted in 2017 and 2018 at two locations in Indiana to evaluate the influence of cover crop species, termination timing, and herbicide treatment on winter and summer annual weed suppression and corn yield. Cereal rye and canola cover crops were terminated early or late (2 wk before or after corn planting) with a glyphosate- or glufosinate-based herbicide program. Canola and cereal rye reduced total weed biomass collected at termination by up to 74% and 91%, in comparison to fallow, respectively. Canola reduced horseweed density by up to 56% at termination and 57% at POST application compared to fallow. Cereal rye reduced horseweed density by up to 59% at termination and 87% at POST application compared to fallow. Canola did not reduce giant ragweed density at termination in comparison to fallow. Cereal rye reduced giant ragweed density by up to 66% at termination and 62% at POST application. Termination timing had little to no effect on weed biomass and density reduction in comparison to the effect of cover crop species. Cereal rye reduced corn grain yield at both locations in comparison to fallow, especially for the late-termination timing. Corn grain yield reduction up to 49% (4,770 kg ha–1) was recorded for cereal rye terminated late in comparison to fallow terminated late. Canola did not reduce corn grain yield in comparison to fallow within termination timing; however, late-terminated canola reduced corn grain yield by up to 21% (2,980 kg ha–1) in comparison to early-terminated fallow. Cereal rye can suppress giant ragweed emergence, whereas canola is not as effective at suppressing large-seeded broadleaves such as giant ragweed. These results also indicate that early-terminated cover crops can often result in higher corn grain yields than late-terminated cover crops in an integrated weed management program.

Orientador: Douglas Soares Galvão Tese (doutorado) - Universidade Estadual de Campinas, Instituto de Física Gleb Wataghin Resumo: Simulações computacionais de sistemas atômico-moleculares despertam enorme interesse em grande parte por ajudar na interpretação de resultados obtidos experimentalmente, pois permitem o acesso de todos os estados estruturais, eletrônicos e dinâmicos, além de permitir estudo de sistemas modelo hipotéticos. É comum existirem dois extremos de complexidade quando se tenta resolver o problema de moléculas e sólidos. De um lado, pode-se optar por um tratamento puramente quântico, por outro, existe a possibilidade de buscar simplificar o problema através da incorporação dos efeitos eletrônicos por um campo de força e seguir com um tratamento clássico restrito às proximidades do equilíbrio. Na presente tese, serão empregadas técnicas abrangendo os dois casos supramencionados, com ênfase em simulações de primeiros princípios baseados em DFT (Density Functional Theory) e de campos de força clássicos com potencial reativo. O principal elemento de interesse é o carbono, que apresenta uma estrutura eletrônica que lhe confere bastante versatilidade para fazer ligações, através de hibridizações dos tipos sp, sp2 e sp3. Tais estados apresentam características eletrônicas peculiares e permitem a formação de uma grande quantidade de estruturas moleculares. Em busca de ajudar na compreensão de estruturas baseadas em cada um dos tipos de hibridização acima descritos, nesta tese são apresentados estudos que não só auxiliam a interpretação experimental, como também propõem estruturas hipotéticas, mas que apresentam viabilidade de síntese experimental. Dessa forma, a presente tese apresenta basicamente cinco trabalhos, a dizer: (i) formação do grafano através da incorporação de hidrogênio em folhas de grafeno (sp2 ?sp3); (ii) nanotubos de carbono de camadas simples (sp2), em busca de uma estrutura com seção reta transversal quadrada; (iii) criação de cadeias atômicas lineares através do estiramento de folhas de grafeno (sp2 ?sp); (iv) receptores moleculares, em que é analisada a dinâmica de incorporação de fulereno (C60) ao chamado buckycatcher (sp2); por fim, (v) simulações em moléculas funcionais conhecidas como nanocarros (sp2 e sp3) Abstract: Computer simulations for atomic and molecular systems play an important role in interpreting experimental results, because they can easily access simultaneously structural, electronic and dynamic states that are experimentally inaccessible. Additionally, simulations can be used to foresee the existence of hipothetic molecular structures. It is often usual to have to deal between two opposites on electronic strucutre approximations when dealing with molecular structures. In one hand, one can apply pure quantum methods, on the other hand on may adopt a more simplified problem by applying classical force fields when dealing with near-to-equilibrium systems. In the present thesis, most of the aforementioned range of simulation techniques will be covered, with emphasis on ab initio simulations based on the density functional theory (DFT) and classical reactive force fields. Carbon is the element that plays a central role in this work, mainly due to its versatile electronic structure which gives it the ability to perform several bond types based on sp, sp2 and sp3hybridization types. Such states present singular electronic features allowing the formation of a myriad of molecular systems. The present thesis presents several studies that have the privilege of being part of both as a helpful guidance on experimental interpretation and the suggestion of hypothetic carbon-based molecular structures. This way, the following research is presented: (i) graphane formation via hydrogen incoporation on graphene sheets (sp2 ?sp3); (ii) single wall carbon nanotubes (sp2) and its yet to be experimentally achieved square cross section representative; (iii) linear atomic chain formation obtained by graphene sheets stretching (sp2 ?sp); (iv) molecular receptors, where the dynamics of fullerene (C60) incoporation on the so-called buckycatcher is analysed (sp2); (v) simulation on functional molecules named nanocars (sp2 and sp3) Doutorado Física Doutor em Ciências

Synthetic-auxin herbicides are often applied for horseweed control before soybean planting. However, certain days of planting interval must be maintained before soybean planting, depending on the product and rate used, because of potential crop phytotoxicity. Halauxifen-methyl is a new synthetic-auxin herbicide for horseweed control in preplant applications in soybean. Field experiments were conducted in 2015 and 2016 in Indiana to evaluate soybean phytotoxicity in response to applications of halauxifen-methyl (5 g ae ha–1) at five preplant intervals (0, 1, 2, 3, and 4 weeks before planting [WBP]). In 2015, soybean phytotoxicity was not observed for any of the preplant intervals at any of the sites. In 2016, 0% to 15% phytotoxicity was observed at 14 d after planting (DAP) when halauxifen-methyl was applied at planting, 1 WBP, and 2 WBP at different sites. Soybean phytotoxicity was expressed in the unifoliate leaves only at 14 DAP. However, the first trifoliate did not show any injury symptoms at 21 DAP from any preplant application timing. Preplant application intervals for halauxifen-methyl did not affect soybean stand counts or grain yield in any site-year. Therefore, field results indicated that halauxifen-methyl applied alone can cause slight soybean phytotoxicity in preplant applications. In growth-chamber bioassays, reductions in soybean biomass, plant length, and emergence were accentuated at 30 C, compared with 20 or 15 C, when halauxifen-methyl was applied at 20 or 40 g ae ha–1. These results contradict the currently held paradigm in which lower temperatures generally increase crop phytotoxicity levels to herbicide soil residual.Nomenclature: 2,4-D; dicamba; halauxifen-methyl; horseweed, Erigeron canadensis L. ERICA; soybean, Glycine max (L.) Merr.

Evolution of glyphosate-resistant (GR) weeds, such as horseweed, presents major challenges in no-till soybean production systems. Effective GR horseweed control with preplant burndown applications is necessary to prevent potential soybean yield losses due to competition and to manage the soil weed seedbank. Halauxifen-methyl is a new synthetic auxin herbicide for broadleaf weed control in preplant burndown applications for soybean and other crops at low use rates (5 g ae ha–1). Experiments were conducted to evaluate the efficacy of herbicide treatments containing halauxifen-methyl for control of GR horseweed in comparison to existing herbicide treatments utilized in no-till GR soybean systems. Glyphosate alone controlled horseweed 33%. Herbicide treatments that included halauxifenmethyl, dicamba, or saflufenacil in combination with glyphosate controlled horseweed 87% to 96%, 89%, and 93%, respectively, 35 d after burndown application (DAB). Horseweed control, horseweed density reduction, and ground cover reduction by halauxifen-methyl plus glyphosate was similar to dicamba plus glyphosate. Horseweed control was greater for halauxifen-methyl plus glyphosate than for 2,4-D plus glyphosate. Cloransulam, cloransulam plus flumioxazin, and cloransulam plus sulfentrazone added to halauxifenmethyl plus glyphosate increased horseweed control and reduced horseweed density. No herbicide injury or soybean yield reduction was observed for treatments containing halauxifen-methyl.Nomenclature: 2,4-D; dicamba; glufosinate; glyphosate; halauxifen-methyl; saflufenacil; horseweed, Conyza canadensis (L.) Cronq. ERICA; soybean, Glycine max (L.) Merr.

Background: Previous studies suggested that individuals with a maternal history of Alzheimer’s Disease(AD) are at higher risk of developing AD than individuals with a paternal history of AD. One could suggest that intra-uterine interactions might be responsible for elevating this risk. In this context, AD rodent models are highly suited for improving our understanding of this matter since animals reach adulthood in a few months. Objective: Here, we aimed at investigating changes in memory-related processes and brain metabolism on the offspring born to transgenic mothers harboring human APP/PS1 mutations. Methods: Rats born to F344-AD(Tg-AD) and WT mothers were evaluated in two different time-points: ~5.5, and ~9.5 months. Y-maze test was used to evaluate spatial working memory and micro-PET [18F]FDG was used to assess brain glucose metabolism. Results: Y-maze test demonstrated that rats born to transgenic mothers presented memory disturbances, indexed by spontaneous alternation, at ~5.5 months and ~9.5 months (figure 1A), while rats born to WT mothers and Tg-AD fathers exhibited a decline in spontaneous alternation only at ~9.5 months. rats born to AD-Tg mothers present brain glucose hypermetabolism at ~9,5 months. Conclusion: Our findings demonstrate that rats born to AD-Tg mothers harboring APP/PS1 mutations present cognitive decline and brain glucose metabolism abnormalities earlier than those born to WT mothers. Further studies are needed to understand the biological basis behind this phenomenon.

Synthetic auxin herbicides such as 2,4-D and dicamba are often utilized to control broadleaf weeds in preplant burndown applications to soybean. Halauxifen-methyl is a new synthetic auxin herbicide for broadleaf weed control in preplant burndown applications to corn, cotton, and soybean at low use rates (5 g ae ha-1). Field experiments were conducted to evaluate efficacy and weed control spectrum of halauxifen-methyl applied alone and in mixtures with 2,4-D (560 g ae ha-1), dicamba (280 g ae ha-1), and glyphosate (560 g ae ha-1). Glyphosate-resistant (GR) horseweed was controlled with halauxifen-methyl applied alone (90% control) and in mixtures (87% to 97% control) 35 d after treatment (DAT). Common ragweed was controlled 93% with halauxifen-methyl applied alone and 91% to 97% in mixtures 35 DAT. Halauxifenmethyl applied alone resulted in poor giant ragweed control 21 DAT (73% control); however, mixtures of halauxifen-methyl with 2,4-D, dicamba, or glyphosate controlled giant ragweed (86% to 98% control). Halauxifen-methyl alone resulted in poor redroot pigweed control (62% control) 21 DAT; however, mixtures of halauxifen-methyl with dicamba, 2,4-D, or glyphosate controlled redroot pigweed (89% to 98% control). Halauxifen-methyl controls GR horseweed and common ragweed applied alone and in mixtures with other synthetic auxin herbicides and glyphosate. Furthermore, mixing 2,4-D or dicamba with halauxifen-methyl can increase the weed control spectrum in preplant burndown applications.Nomenclature: 2,4-D; dicamba; glyphosate; halauxifenmethyl; common ragweed, Ambrosia artemisiifolia L. AMBEL; giant ragweed, Ambrosia trifida L. AMBTR; horseweed, Conyza canadensis (L.) Cronq. ERICA; redroot pigweed, Amaranthus retroflexus L. AMARE; corn, Zea mays L.; cotton, Gossypium hirsutum L.; soybean, Glycine max (L.) Merr

The concept of a hybrid operating room represents the union of a high-complexity surgical apparatus with state-of-the-art radiological tools (ultrasound, CT, fluoroscopy, or magnetic resonance imaging), in order to perform highly effective, minimally invasive procedures. Although the use of a hybrid operating room is well established in specialties such as neurosurgery and cardiovascular surgery, it has rarely been explored in thoracic surgery. Our objective was to discuss the possible applications of this technology in thoracic surgery, through the reporting of three cases.

Glycine is the simplest among all naturally occurring amino acids, presenting an hydrogen atom in its side chain and for this reason it is the only non-chiral. In its gaseous phase, glycine appears in a non-ionic structure, whereas in solution or crystal, it takes an ionic or zwitterionic form. Although at molecular level, there is no L- or D-glycine, it presents great versatility in its crystalline phase related to the existence of several polymorphs, which the three most studied are: α-, β- or γ-glycine, containing four, two and three molecules per unit cell, respectively. First principles calculations based on the density functional theory within the generalized gradient approach (DFT-GGA) using the PBE functional were performed. Three different approaches for accounting core electrons were used: (i) all electron (AE); (ii) ultra-soft pseudopotencials (USP); and (iii) norm-conserving pseudopotentials. Lattice parameters are in good greement with those previously published from both experimental and theoretical works. The crystal stability was studied by both the energy per molecule and Mulliken populational analysis, accounting also for the core electron binding energy. This way, the stability sequence was taken as α > β > γ, being the α polymorph the most stable structure, which is in agreement with the previously published results by Chisholm et. al. (J. A. Chisholm et. al., Crystal Growth & Design 5(4), 1437, 2005) from DFT simulations. However, this result confronts experimental results, which account for the γ > α > β stability sequence. Optical absorption was computed, showing that γ-glycine presents the lowest dependence with the incident radiation polarization amongst all polymorphs studied. All glycine phases presented indirect band gaps. Optical absorption and X-ray photoelectron spectroscopy (XPS) experiments were made for α-glycine grown by the standard solvent slow evaporation method using ultrapure commercially-obtained glycine powder (> 99%) and Milli-Q water. The absorption spectra showed the existence of a 5, 11 ± 0.02 eV direct energy band gap, and the XPS showed the binding energy for core electrons for non-hydrogen atoms and also showed the presence of chlorine and sodium atoms in α-glycine crystals. These experimental results were interpreted by comparison with first principles calculations. The calculated absorption spectra showed great dependence with the incident radiation polarization, due to the molecular space arrangement, which generates the greatest electric dipole within 100 direction. XPS was interpreted analyzing the partial density of states for every element and functional group obtained by AE calculations, and also by comparing 1s orbital energies for non-hydrogen atoms. The difference between theoretically predicted binding energies was lower than 5%. Luminescence spectra were obtained for temperatures varying from 4 K to 300 K for α-glycine crystals. Time-dependent density functional theory calculations were performed in order to assign molecular signature for the 3,4 eV peak in the luminescence spectra. The present dissertation also includes calculations for binding energies between the Tetracycline (Tc) antibiotic with its binding site at the protein Tet responsive to Tc (TetR). Tc are a family of broad spectrum antibiotics, which exhibits activity against several gam-positive and gram-negative bacteria. The interaction energies were computed for all Tc interacting residues of Tetr, constrained to their atomic positions obtained experimentally, with structure available at Protein Data Bank within ID 2TCT. Energy calculations were performed within DFT-GGA using the hybrid functional proposed by Becke-Lee-Yang-Parr (BLYP) and taking the double numerical plus polarization (DNP) basis set with an orbital cutoff of 4.9 ˚A. Our results are in overall good agreement with previously proposed interaction energies, though Met177 presents a great discrepancy, related to fact that calculations lead to greater interaction intensity than it is expected experimentally. Despite this fact, our results suggest that the methodology employed can be extended to other systems with relative confidence and also, which changes can be made in order to increase the antibiotic activity Glicina é o mais simples dos aminoácidos protéicos existentes e o único não quiral, tendo como cadeia lateral um átomo de hidrogênio. Na forma gasosa, ela se apresenta em forma não-iônica, enquanto que em solução ou cristal, ela assume uma forma iônica chamada de zwitterion. Embora em termos moleculares não exista L- ou D-glicina, ela apresenta grande versatilidade em sua forma cristalina, ocorrendo em várias fases polimórficas, dentre as quais as três principais são: ?-, ?- ou ?-glicina, contendo respectivamente quatro, duas e três moléculas por célula unitária. Na presente dissertação, foram realizados cálculos de primeiros princípios baseados na aproximação do gradiente generalizado da teoria do funcional da densidade (DFT-GGA) usando o funcional PBE para as seguintes formas de tratamento dos elétrons de caroço: todos os elétrons (TE), pseudopotenciais ultramacios e pseudopotenciais de norma conservada (NC). Critérios elevados de convergência foram adotados e os resultados estruturais obtidos coincidem satisfatoriamente com os resultados experimentais e teóricos existentes na literatura. A estabilidade cristalina foi estudada tanto pela energia por molécula, quanto pela análise populacional de Mulliken e energias de ligação dos elétrons de caroço. Foi obtida a seqüência ?>?>?, onde ? é o polimorfo mais estável, em detrimento da ordem de estabilidade obtida experimentalmente (?>?>?). Essa discordância, entretanto está em acordo com o já obtido por Chisholm et. al. (J. A. Chisholm et. al., Crystal Growth & Design 5(4), 1437, 2005). A absorção ótica foi calculada, e mostrou que o cristal de ?-glicina apresenta uma menor dependência com a polarização da radiação incidente que os outros polimorfos estudados. Todos os polimorfos apresentaram gaps indiretos na estrutura de banda. Além das simulações teóricas, foram feitas medidas de absorção ótica e espectroscopia de fotoelétron de raios-X (XPS) apenas em cristais de ?-glicina crescidos através do método de evaporação lenta de solvente. Da absorção, foi obtido um gap de energia de 5,11 ± 0.02 eV, enquanto que do XPS foram obtidas as energias de ligação dos elétrons em orbitais profundos para os átomos de C, N e O. Além disso, a análise do XPS detectou a presença de cloro e sódio, em baixas concentrações. A interpretação dos resultados experimentais foi feita comparando com os resultados obtidos teoricamente pelos três métdos descritos acima. A absorção calculada apresenta grande dependência com a polarização da radiação incidente, devido ao arranjo espacial das moléculas de glicina que cria uma resultante dipolar na direção 100. O XPS foi interpretado analisando as densidades parciais de estados eletrônicos obtidas através dos cálculos com TE, além da comparação entre os níveis de orbitais 1s para os átomos não hidrogênio. Nesse caso, a diferença entre os resultados experimentais e os teóricos foi inferior a 5%. Medidas de luminescência foram feitas em cristais de ?-glicina com temperaturas variando de 4 K a 300 K. Cálculos baseados na teoria do funcional da densidade dependente do tempo foram realizados e permitiram o assinalamento do pico em 3,4 eV no espectro de luminescência como sendo uma assinatura molecular. Por fim, como aplicação, foram calculadas as energias de interação do antibiótico Tetraciclina (Tc) com os resíduos de aminoácidos pertencentes ao sítio de ligação da proteína repressora Tet responsiva à Tc (TetR). Tc são uma família de antibióticos de largo espectro que exibem atividade contra um grande número de bactérias gram-positiva e gram-negativa. As energias de interação foram computadas para todos os resíduos da TetR (aminoácidos do sítio de ligação) interagentes com a Tc, a partir das posições atômicas obtidas experimentalmente e disponibilizadas no Protein Data Bank sob a identificação 2TCT. Os cálculos de energia foram realizados através da teoria do funcional da densidade com a aproximação do gradiente generalizado (DFT-GGA) em conjunto com o funcional híbrido de correlação e troca proposto por Becke-Lee-Yang-Parr (BLYP). Foi usado o conjunto de base numérica dupla com polarização (DNP) com um raio orbital de corte de 4,9 Å. Os resultados obtidos são coerentes com os já propostos, a menos de uma discrepância na interação entre a Met177 e a tetraciclina, que está muito mais intensa que a esperada. Apesar disso, os resultados sugerem que a metodologia empregada possa ser utilizada em outros sistemas, além de sugerir quais modificações na estrutura da Tc podem ser feitas de forma a potencializar a ação antibiótica.

mostra a economia de um centro de tratamento especializado, realizando um servico de segunda opiniao. Alem dos achados de carater economico, chama atencao a divergencia de opinioes quanto a conduta terapeutica, evidencia­das por meio de um algoritmo de segunda opiniao, iniciado apos uma indicacao ini­cial de cirurgia de coluna. O possivel vies conservador deste algoritmo foi minimi­zado pela liberdade conferida aos pacien­tes de recusarem a participar, e de poder realizar a cirurgia com o medico de origem nos casos em que se confirmava a indica­cao cirurgica. Aproximadamente 75% dos casos que tinham uma indicacao cirurgica poderiam ter sido tratados sem cirurgia. A falta de diretrizes de tratamento, baseadas em evidencias, para as doencas que afetam a coluna vertebral e uma rea­lidade. A revisao sistematica de Cheng et al. clama pela necessidade do desen­volvimento de diretrizes para tratamento de doencas da coluna vertebral com ade­quada qualidade metodologica, transpa­rencia, e consistencia com as diretrizes do