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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.
21

The effect of cattle winter feeding systems on soil nutrients, forage growth, animal performance, and economics

Jungnitsch, Paul F. 26 May 2008 (has links)
Overwintering of cows is a major cost in a cow-calf production system on the prairies. Winter feeding hay and straw directly on pasture is a potentially more efficient and economical system compared to conventional drylot feeding in a yard. The objectives of the research described in this thesis were to compare winter feeding cattle directly on pasture to traditional drylot over-wintering of cattle and the associated mechanized spreading of manure on pasture. This trial compared the effects of winter feeding systems on pasture nutrient distribution, nutrient recovery in soil and forage, pasture forage response, cattle performance, and economics. <p>The experiment was conducted at Lanigan, SK, on an old russian wildrye grass pasture. Pasture nutrient levels and distribution were measured before and after winter feeding, as well as forage yield, and cattle weight and condition. Nutrient capture and cycling was assessed along with the economics of the different systems. In the pasture fed systems, cattle were fed by either bale processing or bale grazing methods over the winter of 2003-2004. Cattle concentration was 2080 cow-days ha-1, with the cattle in the field for 130 d. In the intensive system used for comparison, cattle were fed in a drylot and 67 tonnes ha-1 of raw manure or 22 tonnes ha-1 of compost was mechanically spread on the pasture in the fall of 2003.<p>Soil inorganic nitrogen (N) levels (0-15 cm) measured in the spring where the cattle were winter fed on pasture were 3 to 4 times the unfertilized, unmanured control treatment, with a mean gain of 117 kg N ha-1. Soil inorganic N was not significantly elevated where manure or compost had been spread by machine. Soil extractable potassium (K) was doubled on the winter feeding sites, with a mean gain of 1209 kg K ha-1. Soil extractable K did not increase where manure or compost had been spread mechanically. Soil distribution patterns of both nutrients were highly uneven following pasture feeding, with levels of inorganic soil N ranging from 12 to 626 kg ha-1 and extractable soil K ranging from 718 to 6326 kg ha-1. Additional nutrients in surface residue from uneaten feed, bedding, and manure were also heavy and variable following pasture feeding. Greater retention of N and K from urine added directly to the soil in the field in the bale grazing and bale processing systems compared to the drylot system is believed to be responsible for high soil available N and K levels compared to manure hauled from the drylot into the field.<p>Soil extractable phosphorus (P) levels (0-15 cm) were measured in the fall of 2005. The compost treatment had the largest increase at 2.6 times the control, an additional 46 kg ha-1. Mean soil P levels did not increase significantly where the cattle were wintered.<p> Over 18 months and 3 harvests, forage dry matter yields where the cattle were fed on pasture were 3 to 5 times the control where the cattle were fed on the pasture, and 1.4 to 1.7 times the control where raw manure or compost was mechanically spread. Also, protein content of the forage was increased to a greater extent in the in-field feeding compared to hauled raw manure or compost, reflecting a greater conservation of N.<p>The gain of N in the forage over 18 months on the winter feeding sites was 200 kg ha-1 of N, almost double what was measured in soil inorganic forms. Fourteen kg ha-1 of P was also recovered. This represented 34% of original feed N and 22% of original feed P that was imported into the field. Recovery of nutrients applied in the raw manure and compost sites was much lower, with only 7% recovery of N and 4% recovery of P in the forage. This was calculated to be 1% of original feed N and 3% of original feed P.<p>The system by which the cattle were overwintered had little influence on cattle weight and condition. All systems performed favorably in maintaining body weight and condition over the winter. Some slight advantages in cattle weight gain and condition were found on the winter feeding systems compared to the in-yard drylot that appeared to be related to slightly increased feed intake.<p>Economic calculations favored winter feeding directly on the pasture by 25% over the drylot systems when the feed value of additional pasture growth over 18 months was included and by 56% when the value of additional soil nutrients was factored in. Feed costs were similar between the systems but pasture feeding had savings in machinery use, fuel consumption and manure handling costs, and gains in pasture productivity.<p>Systems that winter fed cattle directly on pasture provided gains in nutrient cycling efficiencies, pasture growth, and economic savings compared to drylot feeding systems, while maintaining similar cattle growth and condition.
22

Water as a common resource - Whose responsibility? : A Study on the Efficiency of Community Involvement in Water Management in India

Rönneke, Johanna January 2009 (has links)
The aim of this study was to evaluate the impact of community involvement on management of water tanks in the Arkavathi sub-basin in the state of Karnataka, South India. Water management was analysed from a socio-environmental perspective, with emphasis on village-level stakeholders’ roles and perceived responsibility. The efficiency of community participation was investigated by comparing two villages having undergone the same World Bank launched program to restore water bodies traditionally used to sustain the livelihood of the rural population. In one village there was a resistance towards how the implementation of the tank rejuvenation project had been performed, in the other there was no local involvement. A minor field study was conducted by visiting the two villages. Qualitative interviews were held with village-level stakeholders of three age groups, to analyse changes over time in knowledge and attitudes. Additionally, ocular observation and photo documentation were made of the study areas. Some informal interviews were carried out with members of an external non-governmental organisation and locals in the study villages. The collected data were analysed by comparing the results for the two villages, as well as the results of the different age groups and genders. There were significant differences in awareness and sense of responsibility, but not knowledge, between the two villages. In the village with a community involvement resisting the governmental scheme for tank renovation, this involvement had proved to be of some advantage to the local community. Contrary to the guidelines, the governmental implementation of the water management strategy did not include local stakeholders’ participation, nor were the tanks restored. Overall, the villagers considered the tank management to be the responsibility of external authorities. There were generally no significant differences between the age groups or men and women, though there were indications of a lower level of knowledge and awareness in women. Absence of effective institutions for water management on all levels as well as difficulties in mainatining efficient village level leadership for community participation are factors causing a major gap between planning and implementation.
23

The Age of Obsolescence: Senescence and Scientific Rejuvenation in Twentieth Century America

Lamb, Erin Gentry 11 December 2008 (has links)
<p>Growing "old" in contemporary American society often means being seen as a problem: you threaten the stability of Social Security and Medicare; cutting-edge science seeks a cure for what ages you; cosmetic companies and health magazines sell you products and strategies for holding on to your youth as long as possible. <em>The Age of Obsolescence: Senescence and Scientific Rejuvenation in Twentieth Century America</em> traces the emergence of these attitudes toward old age back to the turn of the twentieth century when a publicly shared conception of aging was emerging in relation to advances in science and medicine, industrialized labor practices, a slowly developing welfare state, demographic observations of increased life expectancy, changing gender roles and expressions of national identity. During that time, the quest for the fountain of youth shifted from the stuff of legend to a driving motivation behind modern science.</p><p>In the four chapters of this dissertation, I bring literary critical methods to bear on literary and scientific texts, public health tracts, journalistic accounts, advertisements and public records. Through this survey of science, government and popular culture, I document the formation of several cultural narratives of aging--or, formulaic ways of addressing aging produced by repeated metaphors, imagery and story lines--that circulated with reciprocal influence through all of these spheres, determining attitudes toward, and experiences of, aging at that moment and into the present. After briefly exploring our contemporary "anti-aging" culture, the four chapters of <em>The Age of Obsolescence</em> address the framing of a moral responsibility for aging individuals to "take care of themselves" as a duty to their nation; the association of aging with obsolescence and its influence on worker's experiences and industrial practices; the scientific and cultural construction of aging as a disease in need of professional intervention; and the proposed "cure" for this problem of aging: scientific rejuvenation, particularly the glandular rejuvenation fad of the 1920s. My conclusion traces this fervor for scientific rejuvenation into the present, showing how the turn-of-the-century cultural logic of aging has become a taken-for-granted framework of American popular culture today. In illuminating the historical moment when the "problem" of aging was located in the bodies of aged individuals, I point toward solutions that may arise not from scientific discovery, but from rewriting these cultural narratives of aging and old age and restructuring the national practices that stem from them.</p> / Dissertation
24

Multi-State Reliability Analysis of Nuclear Power Plant Systems

Veeramany, Arun January 2012 (has links)
The probabilistic safety assessment of engineering systems involving high-consequence low-probability events is stochastic in nature due to uncertainties inherent in time to an event. The event could be a failure, repair, maintenance or degradation associated with system ageing. Accurate reliability prediction accounting for these uncertainties is a precursor to considerably good risk assessment model. Stochastic Markov reliability models have been constructed to quantify basic events in a static fault tree analysis as part of the safety assessment process. The models assume that a system transits through various states and that the time spent in a state is statistically random. The system failure probability estimates of these models assuming constant transition rate are extensively utilized in the industry to obtain failure frequency of catastrophic events. An example is core damage frequency in a nuclear power plant where the initiating event is loss of cooling system. However, the assumption of constant state transition rates for analysis of safety critical systems is debatable due to the fact that these rates do not properly account for variability in the time to an event. An ill-consequence of such an assumption is conservative reliability prediction leading to addition of unnecessary redundancies in modified versions of prototype designs, excess spare inventory and an expensive maintenance policy with shorter maintenance intervals. The reason for this discrepancy is that a constant transition rate is always associated with an exponential distribution for the time spent in a state. The subject matter of this thesis is to develop sophisticated mathematical models to improve predictive capabilities that accurately represent reliability of an engineering system. The generalization of the Markov process called the semi-Markov process is a well known stochastic process, yet it is not well explored in the reliability analysis of nuclear power plant systems. The continuous-time, discrete-state semi-Markov process model is a stochastic process model that describes the state transitions through a system of integral equations which can be solved using the trapezoidal rule. The primary objective is to determine the probability of being in each state. This process model ensures that time spent in the states can be represented by a suitable non-exponential distribution thus capturing the variability in the time to event. When exponential distribution is assumed for all the state transitions, the model reduces to the standard Markov model. This thesis illustrates the proposed concepts using basic examples and then develops advanced case studies for nuclear cooling systems, piping systems, digital instrumentation and control (I&C) systems, fire modelling and system maintenance. The first case study on nuclear component cooling water system (NCCW) shows that the proposed technique can be used to solve a fault tree involving redundant repairable components to yield initiating event probability quantifying the loss of cooling system. The time-to-failure of the pump train is assumed to be a Weibull distribution and the resulting system failure probability is validated using a Monte Carlo simulation of the corresponding reliability block diagram. Nuclear piping systems develop flaws, leaks and ruptures due to various underlying damage mechanisms. This thesis presents a general model for evaluating rupture frequencies of such repairable piping systems. The proposed model is able to incorporate the effect of aging related degradation of piping systems. Time dependent rupture frequencies are computed and the influence of inspection intervals on the piping rupture probability is investigated. There is an increasing interest worldwide in the installation of digital instrumentation and control systems in nuclear power plants. The main feedwater valve (MFV) controller system is used for regulating the water level in a steam generator. An existing Markov model in the literature is extended to a semi-Markov model to accurately predict the controller system reliability. The proposed model considers variability in the time to output from the computer to the controller with intrinsic software and mechanical failures. State-of-the-art time-to-flashover fire models used in the nuclear industry are either based on conservative analytical equations or computationally intensive simulation models. The proposed semi-Markov based case study describes an innovative fire growth model that allows prediction of fire development and containment including time to flashover. The model considers variability in time when transiting from one stage of the fire to the other. The proposed model is a reusable framework that can be of importance to product design engineers and fire safety regulators. Operational unavailability is at risk of being over-estimated because of assuming a constant degradation rate in a slowly ageing system. In the last case study, it is justified that variability in time to degradation has a remarkable effect on the choice of an effective maintenance policy. The proposed model is able to accurately predict the optimal maintenance interval assuming a non-exponential time to degradation. Further, the model reduces to a binary state Markov model equivalent to a classic probabilistic risk assessment model if the degradation and maintenance states are eliminated. In summary, variability in time to an event is not properly captured in existing Markov type reliability models though they are stochastic and account for uncertainties. The proposed semi-Markov process models are easy to implement, faster than intensive simulations and accurately model the reliability of engineering systems.
25

Diferentes formas de propagação e intensidades de poda no desempenho a campo de mirtileiros do grupo rabbiteye. 2011. / Different methods of propagation and intensity of pruning on field performance of rabbiteye blueberries.

Souza, André Luiz Külkamp de 02 March 2011 (has links)
Made available in DSpace on 2014-08-20T14:22:08Z (GMT). No. of bitstreams: 0 Previous issue date: 2011-03-02 / Blueberry cultivars of rabbiteye group Bluegem, Briteblue, and Woodard are characterized by having low chilling requirement, high vigor and productivity, being able to be produced in region of Southern Brazil. Studies on cultural practices and field performance in blueberry are recent in Brazil. In order to provide more accurated informations to the growers of this fruit crop, experiments were carried out during 2009 and 2010 in a high potential region. The first experiment was carried out in a didactic orchard at the Federal University of Pelotas (Rio Grande do Sul State), and the objective was to study the field behavior of the blueberries propagated by two different techniques. Evaluations on vegetation, production, and fruit quality aspects were done in order to determine the effect of rejuvenation obtained through micropropagation technique. One year-old plants of blueberry, cultivars Bluegem, Briteblue, and Woodard, obtained from micropropagation and semi-hardwood cuttings were used. It was found that micropropagated plants showed a high initial vegetative growth, and both productivity and fruit quality similar to plants propagated by cuttings. In the second experiment, conducted in a commercial orchard located in the same city of the first experiment, it was tested different intensities of pruning on production and fruit quality aspects. Seven years-old plants, cultivars Briteblue and Woodard were used. They were pruned during the winter rest period in different intensities (low, moderate, drastic and control), and the control (no pruning). Blueberry plants which were not pruned showed high productivity, but produced smaller fruits. The moderate pruning system showed the best results. / As cultivares de mirtileiro Bluegem, Briteblue e Woodard pertencem ao grupo rabbiteye e caracterizam-se pela baixa exigência em frio, elevado vigor e alta produtividade, sendo aptas a serem produzidas nas condições do Sul do Brasil. No país ainda são recentes os estudos relativos ao manejo do pomar de mirtileiro e suas características a campo. Na tentativa de oferecer informações mais precisas aos produtores desta cultura, foram conduzidos dois experimentos durante os anos de 2009 e 2010 em região com potencial produtivo. O primeiro experimento foi conduzido em pomar didático pertencente à Universidade Federal de Pelotas, e o objetivo foi estudar o comportamento a campo de mirtileiros propagados por duas diferentes técnicas, avaliando-se aspectos vegetativos, produtivos e de qualidade dos frutos, a fim de constatar o efeito do rejuvenescimento obtido através da técnica de micropropagação. Para isso, realizou-se o plantio de mudas de mirtileiro com um ano de idade das cultivares Bluegem, Briteblue e Woodard, propagadas in vitro e por estaquia semilenhosa. Foi constatado que plantas micropropagadas apresentam, a campo, crescimento vegetativo inicial superior, além de produtividade e qualidade de frutos semelhantes às plantas propagadas por estaquia. No segundo experimento, conduzido em um pomar comercial localizado no mesmo município do primeiro, foram testadas diferentes intensidades de poda de frutificação e avaliados aspectos produtivos e de qualidade de frutos. Foram utilizadas plantas com sete anos de idade, das cultivares Briteblue e Woodard, que foram podadas no período de repouso hibernal em intensidades distintas (leve, moderada, drástica e testemunha). Plantas de mirtileiro não podadas apresentaram produtividade superior, porém produziram frutos de menor tamanho. O sistema de poda moderado foi o que apresentou melhores resultados.
26

Avaliação do potencial de derivados do ácido kójico sobre a melanogênese e o envelhecimento cutâneo

Pedrosa, Tatiana do Nascimeto 25 February 2013 (has links)
Submitted by Lúcia Brandão (lucia.elaine@live.com) on 2015-12-09T19:09:16Z No. of bitstreams: 1 Dissertacao - Tatiana do Nascimento Pedrosa.pdf: 4183067 bytes, checksum: b4d1e2566da171bad171597268e6c941 (MD5) / Approved for entry into archive by Divisão de Documentação/BC Biblioteca Central (ddbc@ufam.edu.br) on 2016-01-19T20:32:30Z (GMT) No. of bitstreams: 1 Dissertacao - Tatiana do Nascimento Pedrosa.pdf: 4183067 bytes, checksum: b4d1e2566da171bad171597268e6c941 (MD5) / Approved for entry into archive by Divisão de Documentação/BC Biblioteca Central (ddbc@ufam.edu.br) on 2016-01-19T20:33:36Z (GMT) No. of bitstreams: 1 Dissertacao - Tatiana do Nascimento Pedrosa.pdf: 4183067 bytes, checksum: b4d1e2566da171bad171597268e6c941 (MD5) / Made available in DSpace on 2016-01-19T20:33:37Z (GMT). No. of bitstreams: 1 Dissertacao - Tatiana do Nascimento Pedrosa.pdf: 4183067 bytes, checksum: b4d1e2566da171bad171597268e6c941 (MD5) Previous issue date: 2013-02-25 / FAPEAM - Fundação de Amparo à Pesquisa do Estado do Amazonas / The continuous sun exposure is a major factor causing oxidative stress, stains and aging skin. The growth of the cosmetics market in the world, the growing interest of people for youthful skin, free of wrinkles and spots, has stimulated researchers to search for new assets for this purpose. Kojic acid is a well known and widely used depigmenting, mainly produced by fungi of the genus Aspergillus which has also been reported as an antioxidant and rejuvenating. However, kojic acid has disadvantages such as low stability and poor inhibition at low concentrations which encourages researchers to search for more active compounds or changes in the molecule in order to seek more active derivatives, stable and secure. Thus, this work aimed at studying the potential of nine Kojic acid derivatives synthesized by researchers at the Federal University of Pará - UFPA in order to obtain compounds with depigmenting activity, antioxidants and rejuvenating superior to those reported kojic acid. In this study we performed cytotoxicity assays, evaluation of antioxidant activity in vitro and enzyme in vitro inhibition of elastase, tyrosinase, collagenase and hyaluronidase. We evaluated the inhibition of tyrosinase activity and melanin production in B16F10 and alterations on tyrosinase gene expression. Of the nine derivatives studied, only three of them, kojato zinc, kojato copper (Cu-AK) and oleikojato copper (Cu-Ok), showed in vitro inhibitory activity on mushroom tyrosinase and were selected for the present study. The inhibition of tyrosinase in vitro kojato zinc (IC 50 - 30.4 ± 0.89µM) was higher than that presented by the kojic acid (IC50 - 60.2 ± 1.83µM) and its other derivatives Cu-AK (IC50 – 133.3 ± 6.59µM) and Cu-Ok (IC50 - 77.6 ± 4.31µM). These compounds were not cytotoxic to B16F10 cells and human dermal fibroblasts at 100 µM and showed no hemolytic potential at the concentration of 250 µM. The Kojic acid and derivatives, Cu-AK and Cu-Ok, were selected to evaluate the action on melanogenesis and enzymes that act on skin aging, as well as antioxidant activity. AK, AK-Cu and Cu-OK, apresenaram low antioxidant activity in the DPPH assay at 50 µg/mL, however, proved to be powerful metal chelating agents. In the studied concentration, 50 µg/mL, OK-Cu (76.0 ± 5.7%) showed chelating activity slightly higher than the AK (58.9 ± 5.63%) and AK-Cu (57.4 ± 5 24). The tyrosinase activity in B16F10 was strongly inhibited by Cu-AK (86.7%) and Cu- OK (92.5%), melanin production decreased by approximately 60.2% and 61.6% respectively. There were no changes in levels of gene expression of tyrosinase and there was no significant inhibition of other enzymes studied. Our results suggest that the action on melanogenesis observed for Cu-OK and Cu-AK occurs through inhibition of tyrosinase associated with an antioxidant mechanism. The compounds studied have great potential for use as cosmetic depigmenting agents. / A exposição solar contínua é um dos principais fatores causadores de estresse oxidativo, manchas e envelhecimento da pele.O crescimento do mercado de cosméticos no mundo, o interesse cada vez maior das pessoas por uma pele jovem, isenta de rugas e manchas, tem estimulado os pesquisadores na busca por novos ativos com este fim. O ácido kójico é um conhecido e bastante utilizado despigmentante, produzido principalmente por fungos do gênero Aspergillus que tem sido relatado também como antioxidante e rejuvenescedor. Entretanto, o ácido kójico apresenta desvantagens como baixa estabilidade e inibição insatisfatória em baixas concentrações o que estimula os pesquisadores na busca por compostos mais ativos ou modificações na molécula visando a busca de derivados mais ativos, estáveis e seguros. Nesse sentido, este trabalho teve como objetivo estudar o potencial de nove derivados do ácido kójico sintetizados por pesquisadores da Universidade Federal do Pará – UFPA, visando obter compostos com atividades despigmentantes, antioxidantes e rejuvenescedoras superiores às relatadas para o ácido kójico. No presente estudo foram realizados ensaios de citotoxicidade, avaliação da atividade antioxidante in vitro, inibição enzimática in vitro das enzimas elastase, tirosinase, colagenase e hialuronidase, inibição da atividade da tirosinase e da produção de melanina em células B16F10 e expressão gênica da tirosinase (Tyr). Dos nove derivados estudados, apenas três, kojato de zinco, kojato de cobre (Cu-AK) e oleikojato de cobre (Cu-Ok), apresentaram atividade inibitória in vitro sobre a tirosinase de cogumelo e foram selecionados para continuação deste trabalho. A inibição da tirosinase in vitrodo kojato de zinco (CI50 - 30,4 ± 0,89 µM) foi superior a apresentada pelo ácido kójico (CI 50 - 60,2 ± 1,83 µM) e seus outros derivados Cu-AK (CI50 - 133,3 ± 6,59 µM) e Cu-Ok (CI50 – 77,6 ± 4,31 µM). Estes compostos não foram citotóxicos em células B16F10 e fibroblastos de derme humana na concentração de 100 µM e não apresentaram potencial hemolítico em concentrações superiores a 250 µM. O Ácido kójico (AK) e os derivados, CuAK e Cu-Ok, foram selecionados para avaliação da ação sobre a melanogênese e enzimas que atuam no envelhecimento cutâneo, além da atividade antioxidante. AK, Cu-AK e Cu-OK, apresentaram atividade antioxidante inferior a 50 % no ensaio do DPPH a 50 µg/mL, no entanto, mostraram-se potentes agentes quelante de metais. Na concentração estudada, 50 µg/mL, Cu-OK(76,0 ± 5,7 %) apresentou atividade quelante levemente superior a do AK (58,9 ± 5,63 %) e Cu-AK (57,4 ± 5,24). A atividade da tirosinase em B16F10 foi fortemente inibida por Cu-AK (86,7 %) eCu-OK (92,5 %) a produção de melanina diminuiu em cerca de 60,2% e 61,6% respectivamente. Não houve alterações nos níveis de expressão gênica de tirosinase e não foi observada inibição significativa das demais enzimas estudadas. Nossos resultados sugerem que a ação sobre a melanogênese observada para Cu-AK eCu-OK ocorre através da inibição da tirosinase associada a um mecanismo antioxidante. Os compostos estudados apresentam grande potencial para uso cosmético como agentes despigmentantes.
27

Análise retrospectiva das alterações da dinâmica facial após aplicações seriadas de toxina botulínica tipo A / Retrospective analysis of facial dynamic alterations after multiple botulinum toxin A applications

Rodrigo Pinto Gimenez 29 January 2007 (has links)
INTRODUÇÃO: A presença de rugas na face devido à hipercinese muscular é comum nas regiões frontal, glabelar e peri-orbitárias. São descritos diversos métodos para o tratamento das rugas de expressão, como a dermoabrasão, a ablação a laser, o laser não ablativo, preenchimentos, cirurgia e aplicações de toxina botulínica. O tratamento das rugas da face com toxina botulínica tipo A é método consagrado, porém são pouco definidos os efeitos a longo prazo. Este estudo retrospectivo teve como objetivo avaliar as rugas das regiões frontal e glabelar da face em pacientes submetidas a aplicações seriadas da toxina botulínica tipo A com finalidade estética, analisando os intervalos entre as aplicações e as doses utilizadas. MÉTODOS: Foram analisadas 24 pacientes do sexo feminino, submetidas entre 5 a 7 aplicações da toxina botulínica tipo A, no período de julho de 1997 a junho de 2006. O tempo médio de acompanhamento foi de 42,2 (± 4,0) meses e o intervalo médio entre as aplicações de 8 (± 0,51) meses. A idade média observada de início da aplicação foi de 48,0 (± 3,0) anos, e da última aplicação foi de 51,6 (± 3,0) anos. Foram métodos de avaliação a análise da documentação fotográfica de antes da primeira e antes da última aplicação, sendo as rugas frontais e glabelares avaliadas segundo escala padronizada, e dados colhidos dos prontuários. RESULTADOS: A longo prazo, verificou-se: 1) amenização das rugas estáticas da região frontal em 62,5% das pacientes e em 37,5% tais rugas se mantiveram inalteradas; 2) amenização das rugas estáticas da região glabelar em 47,2% das pacientes, em 50% tais rugas se mantiveram inalteradas e em 2,8% verificou-se pouca acentuação; 3) amenização das rugas dinâmicas da região frontal em 84,7% das pacientes e em 15,3% tais rugas se mantiveram inalteradas; 4) amenização das rugas dinâmicas da região glabelar (corrugadores) em 63,9% das pacientes, em 26,4% tais rugas se mantiveram inalteradas e em 9,7% verificou-se pouca acentuação. 5) amenização das rugas dinâmicas da região glabelar (prócero) em 57% das pacientes, em 32% tais rugas se mantiveram inalteradas e em 11% verificou-se pouca acentuação. A média da dose total de toxina botulínica utilizada por sessão no presente estudo foi de 43,83 ± 1,25 U, e a dose total cumulativa foi de 272,08 ± 20,42 U. CONCLUSÕES: No longo prazo, existe maior porcentagem de pacientes com amenização ou aspecto inalterado das rugas estáticas e dinâmicas das regiões frontal e glabelar da face em relação a pacientes com acentuação das mesmas. Não houve variação estatisticamente significativa das médias dos intervalos entre as aplicações. A dose total de toxina botulínica aumentou de forma estatisticamente significativa até a terceira aplicação, mantendo-se sem variação significativa a partir de então. / INTRODUCTION: The presence of wrinkles on the face due to the over activity of muscles is rather common on the frontal, glabellar, and periocular regions. A number of methods for the treatment of face lines, such as skin abrasion, laser resurfacing, fillers, surgery and botulinum toxin A have been described. The treatment of facial rhytids with botulinum toxin A is widely used. However, its long term effects are not well defined. This retrospective study assesses the rhytids of both the frontal and glabellar regions of the face on patients submitted to multiple botulinum toxin A applications for aesthetic use, analyzing intervals between applications and dosages. METHODS: 24 female patients who had undergone 5 to 7 botulinum toxin A applications from July, 1997 to June, 2006 were studied. The mean time of follow up was 42.2 (± 4.0) months and the mean interval between applications was 8 (± 0.51) months. The mean age of the patients at the beginning of application was 48.0 (± 3.0) years old, and 51.6 (± 3.0) years old at the last application. The evaluation was carried through the analysis of photographic documentation from before the first and last applications, and both frontal and glabellar rhytids were evaluated according to standardized scale, as well as data collected from patients charts. RESULTS: the long term analysis demonstrated that: 1) improvement of the static rhytids of the frontal region in 62,5% of patients and such rhytids remained unaltered in 37.5% of the patients; 2) improvement of the static rhytids of the glabellar region in 47.2% of the patients, they remained unaltered in 50% of the patients and there was a slight worsening in 2.8% of the patients; 3) improvement of the dynamic rhytids of the frontal region in 84.7% of patients, and they remained unaltered in 15.3% of the patients; 4) improvement of the dynamic rhytids of the glabellar region (corrugator) in 63.9% of the patients, they remained unaltered in 26.4% of the patients and there was a slight worsening in 9.7% of the patients; 5) improvement of the dynamic rhytids of the glabellar region (procerus) in 57% of the patients, they remained unaltered in 32% and there was a slight worsening in 11% of the patients. The mean total dosage of botulinum toxin A used per session in this study was 43.83 ± 1.25 U, and the total cumulative dosage was 272.08 ± 20.42 U. CONCLUSIONS: In the long run, a higher percentage of patients showed improvement or unaltered aspect of their static and dynamic rhytids of the frontal and glabellar regions of the face, when compared to the patients that showed worsening. There was no variation of the mean intervals between the applications. The total dosage of botulinum toxin was significantly increased up to the third application, and kept stable in the following sessions.
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Diferentes formas de propagação e intensidades de poda no desempenho a campo de mirtileiros do grupo rabbiteye / Different methods of propagation and intensity of pruning on field performance of rabbiteye blueberries

Souza, André Luiz Külkamp de 02 March 2011 (has links)
Made available in DSpace on 2014-08-20T14:22:03Z (GMT). No. of bitstreams: 1 dissertacao_andre_de_souza.pdf: 1505540 bytes, checksum: d992967fc84ee46bcd594a64a2a642a6 (MD5) Previous issue date: 2011-03-02 / Blueberry cultivars of rabbiteye group Bluegem, Briteblue, and Woodard are characterized by having low chilling requirement, high vigor and productivity, being able to be produced in region of Southern Brazil. Studies on cultural practices and field performance in blueberry are recent in Brazil. In order to provide more accurated informations to the growers of this fruit crop, experiments were carried out during 2009 and 2010 in a high potential region. The first experiment was carried out in a didactic orchard at the Federal University of Pelotas (Rio Grande do Sul State), and the objective was to study the field behavior of the blueberries propagated by two different techniques. Evaluations on vegetation, production, and fruit quality aspects were done in order to determine the effect of rejuvenation obtained through micropropagation technique. One year-old plants of blueberry, cultivars Bluegem, Briteblue, and Woodard, obtained from micropropagation and semi-hardwood cuttings were used. It was found that micropropagated plants showed a high initial vegetative growth, and both productivity and fruit quality similar to plants propagated by cuttings. In the second experiment, conducted in a commercial orchard located in the same city of the first experiment, it was tested different intensities of pruning on production and fruit quality aspects. Seven years-old plants, cultivars Briteblue and Woodard were used. They were pruned during the winter rest period in different intensities (low, moderate, drastic and control), and the control (no pruning). Blueberry plants which were not pruned showed high productivity, but produced smaller fruits. The moderate pruning system showed the best results. / As cultivares de mirtileiro Bluegem, Briteblue e Woodard pertencem ao grupo rabbiteye e caracterizam-se pela baixa exigência em frio, elevado vigor e alta produtividade, sendo aptas a serem produzidas nas condições do Sul do Brasil. No país ainda são recentes os estudos relativos ao manejo do pomar de mirtileiro e suas características a campo. Na tentativa de oferecer informações mais precisas aos produtores desta cultura, foram conduzidos dois experimentos durante os anos de 2009 e 2010 em região com potencial produtivo. O primeiro experimento foi conduzido em pomar didático pertencente à Universidade Federal de Pelotas, e o objetivo foi estudar o comportamento a campo de mirtileiros propagados por duas diferentes técnicas, avaliando-se aspectos vegetativos, produtivos e de qualidade dos frutos, a fim de constatar o efeito do rejuvenescimento obtido através da técnica de micropropagação. Para isso, realizou-se o plantio de mudas de mirtileiro com um ano de idade das cultivares Bluegem, Briteblue e Woodard, propagadas in vitro e por estaquia semilenhosa. Foi constatado que plantas micropropagadas apresentam, a campo, crescimento vegetativo inicial superior, além de produtividade e qualidade de frutos semelhantes às plantas propagadas por estaquia. No segundo experimento, conduzido em um pomar comercial localizado no mesmo município do primeiro, foram testadas diferentes intensidades de poda de frutificação e avaliados aspectos produtivos e de qualidade de frutos. Foram utilizadas plantas com sete anos de idade, das cultivares Briteblue e Woodard, que foram podadas no período de repouso hibernal em intensidades distintas (leve, moderada, drástica e testemunha). Plantas de mirtileiro não podadas apresentaram produtividade superior, porém produziram frutos de menor tamanho. O sistema de poda moderado foi o que apresentou melhores resultados.
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Structure-Property Relationships to Understand Comprehensive Rejuvenation Mechanisms of Aged Asphalt Binder

January 2020 (has links)
abstract: This research focused on the structure-property relationships of a rejuvenator to understand the comprehensive rejuvenation mechanism of aged asphalt binder. Aged asphalt such as recycled asphalt shingles (RAS) and reclaimed asphalt pavement (RAP) contain various amounts of asphalt binder. However, the asphalt binder in RAS and RAP is severely aged and inferior in properties compared to a virgin binder. To address this issue, liquid additives have been used under the general title of rejuvenators. That poses an additional challenge associated with the lack of clear metrics to differentiate between softeners and rejuvenators. Therefore, there is a need for a thorough study of rejuvenators. In this study, diverse-sourced rejuvenators have been used in RAS and RAP-modified binders as well as laboratory-prepared aged binders. The properties of the rejuvenated aged binder were characterized at a macro-level and molecular level. The study showed that the performance of the RAS-modified binder was significantly improved after bio-modification by a bio-rejuvenator. This study further evaluated laboratory-prepared aged asphalt rejuvenated with different rejuvenators. The results found that oxidized bitumen became soft after adding rejuvenators, regardless of their source. Molecular dynamics simulation showed that the effective rejuvenator restored the molecular conformation and reduced the size of asphaltene nanoaggregates. The study results showed that due to the specific chemical composition of certain rejuvenators, they may negatively impact the durability of the mixture, especially about its resistance to moisture damage and aging. Computational analysis showed that while the restoration capacity of rejuvenators is related to their penetration into and peptizing of asphaltene nanoaggregates, the durability of the restored aged asphalt is mainly related to the polarizability values of the rejuvenator. Rejuvenators with lower polarizability showed better resistance to aging and moisture damage. In summary, this study develops the rheology-based indicators which relate to the molecular level phenomenon in the rejuvenation mechanism. The rheology-based indicators, for instance, crossover modulus and crossover frequency differentiated the rejuvenators from recycling agents. Moreover, the study found that rejuvenation efficiency and durability are depended on the chemistry of rejuvenators. Finally, based on the learning of chemistry, a chemically balanced rejuvenator is synthesized with superior rejuvenation properties. / Dissertation/Thesis / Doctoral Dissertation Civil, Environmental and Sustainable Engineering 2020
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Development of clonal propagation protocols for Uapaca kirkiana and Pappea capensis, two southern African trees with economic potential

Mngomba, Simon Alfred 30 July 2008 (has links)
Experiments were carried out with the objectives of developing propagation protocols for Uapaca kirkiana and Pappea capensis tree species of southern Africa, and evaluating the graft compatibility within U. Kirkiana tree clones, provenances and species. Reverse phase high performance liquid chromatography (RP-HPLC), Folin-Ciocalteau reagent, fluorescence microscopy and callus fusion methodologies were used to diagnose graft compatibility. Results indicated that U. Kirkiana culture asepsis was achieved with 0.1% w/v mercuric chloride HgCl2) and using pre-conditioned grafted trees. Sodium hypochlorite (NaOCl) improved P. Capensis seed asepsis and germination, and discarding floating seeds improved germination. Murashige and Skoog (MS) medium with 2.0 mg l-1 benzylaminopurine (BAP) and 0.3 mg l-1 casein hydrolysate (CH) was superior in shoot multiplication and 0.5 mg l-1 indole-3-butyric acid (IBA) for rooting of P. Capensis microshoots. For somatic embryogenesis, three quarter strength MS medium with 0.05 mg l-1 thidiazuron (TDZ) and 0.3 mg l-1 CH, or 0.2 mg l-1 BAP with 0.3 mg l-1 CH, were effective in germination of P. Capensis somatic embryos. For U. Kirkiana lateral shoot explants, shoot multiplication was superior on three quarter strength MS medium with 0.1 mg l-1 BAP and 0.3 mg l-1 CH. Rooting of micro-cuttings (36%) was achieved on ½ MS with 2.5 mg l-1 IBA. RP-HPLC, fluorescence microscopy and callus fusion studies showed that phenolic compounds play a major role in U. Kirkiana graft incompatibility. Less graft compatible combinations showed an increase in phenol deposits above the union and graft incompatibility was more pronounced above the union than below the union. Proliferation of parenchymatous tissues was better below the union than above the union. Fluorescence microscopy showed presence of flavonoids and polymers above the union of less graft compatible combinations. The chromatograms showed that ferulic acid was abundant and responsible for wood discolouration. The chromatograms also isolated ρara-coumaric acids which were predominant above the union of the less compatible combinations. Therefore, ρara-coumaric acids, flavonoids and polymers were implicated in graft incompatibility of U. kirkiana trees. Copyright / Thesis (PhD)--University of Pretoria, 2008. / Plant Production and Soil Science / unrestricted

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