Neste trabalho são estudados os parâmetros de verificação do estado limite de deformações excessivas (a relação flecha-altura-a/H) e da estabilidade global (o parâmetro &#945 e o coeficiente &#947z) das estruturas de edifícios. Através da utilização de exemplos de estruturas de trinta (30) edifícios usuais de concreto armado, estabelece-se uma relação entre esses parâmetros, objetivando propiciar ao projetista de estruturas condições de avaliar a eficiência e o grau de confiabilidade de cada um deles. São também discutidos e comparados alguns dos procedimentos usuais para realizar uma análise global de segunda ordem das estruturas. Nesta análise deve-se levar em conta tanto a não-linearidade física (NLF) quanto a geométrica (NLG) e, para tanto, são adotados métodos rigorosos e aproximados. Quer-se com isso, principalmente, analisar o processo simplificado como suficiente para se obter os esforços finais de segunda ordem, uma vez que se pretende incluir tal procedimento na norma brasileira NB-1, atualmente em fase de revisão. / In this work, a servicebility pararneter (displacement-height ratio - a/H) is studied, as well as the global stability parameters of building structures (&#945 and &#947z stability coefficients). By analyzing thirty (30) actual reinforced concrete building structures, a relationship among these parameters (&#945, &#947z and a/H) is achieved aiming to demonstrate to the building structure designers their level of efficiency and reliability for practical purposes. Some standard procedures for global second order structure analysis are also discussed with comparison among them. In this analysis, the material and the geometric non-linearities have to be considered and for that one can adopt approximated and accureted methods. Mainly, the interest is to verify the possibility of using the simplified method as a proper tool to compute the final second order efforts of buildings, once this procedure could be included into the Brazilian Code, NB-1, which is being revised.

The use of nitrogen (N) fertilizer is generally restricted on mixed species forage systems due to its stimulatory effect on grasses which increases competition with legume species. Reduced legume growth from this competition can compromise forage nutritive value and prospective yields. The controlled-release nature of several enhanced efficiency fertilizer N products holds the potential to improve legume persistence in mixed species pastures while providing supplemental N required by the grass component. The studies contained in this dissertation evaluated the effect of different enhanced efficiency N formulations (ATU, ESN, methylene urea, SuperU, and a 75% ESN: 25% urea blend) and untreated urea on yield, nutritive value, and legume persistence in a ‘Wrangler’ bermudagrass and ‘Durana’ white clover mixture (2014-2016 growing seasons), ‘KY-31’tall fescue and ‘Kenland’ red clover mixture (2015-2016 growing seasons), and ‘KY-31’ stockpiled tall fescue (2015-2017). The three studies were conducted at the University of Kentucky Spindletop Research Farm in Lexington, KY in a randomized complete block design. In the bermudagrass-white clover study, all enhanced efficiency N sources maintained white clover populations similar to the unfertilized grass/clover control, but only ESN caused greater clover composition than standard urea. Total forage yields increased linearly with N rate in all years, but dry weather conditions in the second and third years resulted in lower total yield. Forage nutritive value followed general trends throughout each growing season, but ESN’s ability to maintain clover resulted in higher nutritive value. In the tall fescue-red clover, total forage yields curvilinearly increased with N rate in 2015 but did not vary in 2016. ESN and ESN+urea blend treatments retained clover composition similar to that of the unfertilized control. Stockpiled forage yield increased with higher N rates. Enhanced efficiency N fertilizers with the ability to control N release can enhance forage yield while maintaining clover in mixed species swards.

Cool season perennial grasses are the foundation of equine nutrition in the transition zone. The objective of this study was to evaluate forage quality using ADF, NDF, IVTDMD, CP, WSC, and ESC and changes in vegetative swards seasonally, diurnally, across species (Kentucky bluegrass, tall fescue, orchardgrass, and perennial ryegrass) and cultivar. This study was conducted in 2015 and 2017 and plots were maintained vegetatively with two to four week mowing. Morning and afternoon sample collection occurred monthly during the growing season. Samples were flash frozen; freeze dried, ground, and scanned using Near Infrared Reflectance Spectroscopy (NIRS) to predict forage quality. There was a significant year effect; therefore year was analyzed separately. Generally, ADF and NDF were highest for Kentucky bluegrass (30 and 52%), lowest for perennial ryegrass (25 and 46%), and tall fescue and orchardgrass were inconsistent. Crude protein was variable across species and season, ranging 10 to 25%. ADF and NDF concentrations were higher in the morning; IVTDMD, WSC, and ESC were higher in the afternoon; and CP was similar diurnally. In conclusion, forage quality in vegetative cool season grass pastures was sufficient to meet the nutritional needs of most equines, but varied seasonally, diurnally, across species, and cultivar.

In paper pulp production, many details can be optimized. For optimal separation of soap from black liquor, it is important to know the amount of soap in the black liquor. A project to produce a method for sampling black liquor and a method for measuring how much soap is present in black liquor by centrifugation was done at Södra Cell Mönsterås. Through centrifugation faster analysis can be done. It took a long time to develop a satisfactory sampling method, but with the help of careful checking of temperature and time, a method was achieved that worked at temperatures between 90 and 100°C, which were the temperatures that were most frequently found, but are higher than the optimum temperature for soap separation. The black liquor turned out to be inhomogeneous, so the project failed to obtain an optimal analysis method within the framework of this project. In the experiment, the centrifuge settings were optimized to 87°C, 2500 rpm and 10 minutes Further attempts could provide more optimal settings for the centrifuge and a substitute for black liquor could make a validation of the centrifuge possible. / Pappersmassaproduktion är komplex, och en rad faktorer kan optimeras. En viktig parameter vid såpavskiljning är innehållet såpa i svartlut eftersom en värdefull produkt, tallolja utvinns av såpa. Projektet syftar till att ta fram en metod för provtagning av svartlut och en metod för att mäta halten såpa i svartluten genom centrifugering. Genom centrifugering kan snabbare analyser göras.  Arbetet har utförts på Södra Cell Mönsterås. Arbetet att utveckla en tillfredsställande provtagningsmetod var komplicerad, men med hjälp av noggrann koll på temperatur och tid uppnåddes en metod som fungerade vid temperaturer mellan 90 och 100°C, vilket var de temperaturer som oftast fanns, men som är högre än optimal temperatur för såpavskiljning. Svartluten visade sig vara inhomogen, därför lyckades det inte att få fram en optimal analysmetod inom ramen av detta projekt. I försöket optimerades centrifugens inställningar till 87°C, 2500 rpm (varv per minut) och 10 minuter. Vidare försök skulle kunna ge mer optimala inställningar för centrifugen genom den utvecklade prov, och ett substitut för svartlut skulle kunne göra en validering av centrifugen möjlig.

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Graduation date: 1998

Endophytic fungi (A. coenophialum and A. lolii) which infect grasses produce ergot alkaloids that serve as the grasses' chemical defenses and enhance the vigor of the grass. Turf-type tall fescue with high endophyte levels has been deliberately developed to produce a greener, more vigorous, pest-resistant turf. Consumption of endophyte-infected grass causes various toxicity symptoms in livestock. Cattle in the southeastern and midwestern United States, where tall fescue is grown on 14 million hectares, often develop signs of toxicosis during summer months from grazing plants in fected by A. coenophialum. A more severe form of the disease, fescue foot, has been associated with cold environment and reported in late fall and winter months not only in the southeastern United States but also in the northwest United States. In New Zealand, where perennial ryegrass is grown on 7 million hectares of pasture, sheep often develop a condition called ryegrass staggers from grazing plants infected by A. lolii. New Zealand reports economic losses grazing plants infected by A. lolii. New Zealand reports economic losses associated with the sheep industry of $205 million per year. In the United States, economic losses associated with the beef cattle industry alone is estimated at $600 million per year. Range finding experiments and case studies of fescue foot and perennial ryegrass staggers (PRGS) were conducted on cattle and sheep under grazing and barn conditions. The main objective was to determine threshold levels of the endophyte toxins, ergovaline (EV) (appendix 1) and lolitrem B (appendix 2), associated with the diseases of fescue foot and PRGS respectively. Fescue foot was experimentally induced in cattle under barn studies in the spring with 825 ppb ergovaline. The ergovaline contaminated feed was given for a period of 42 days. Similar barn studies in sheep in spring to early summer did not produce clinical fescue foot with up to 1215 ppb. Field studies of natural fescue foot in a herd of sheep were conducted, (ie 540 ppb) values of ergovaline in the feed, but clinical disease was not produced in late fall through winter. A case study from a herd of sheep revealed 813 ppb dietary ergovaline had produced fescue foot in the months of fall (November). Fields of perennial ryegrass (PRG) where sheep received 2,135 ppb lolitrem B toxin were associated with clinical cases of PRGS in 42 sheep of 237 sheep (18 percent incidence rate) in the Willamette Valley of Oregon. Three months later, sheep on this same field which then had 1,465 ppb lolitrem B, did not have PRGS. These were the first range finding experiments undertaken in this locale to document threshold levels of endophyte toxins associated with fescue foot and PRGS. / Graduation date: 1994

<p>Modern methods for managing pine (<em>Pinus sylvestris</em>) create homogenized forests. This decreases nature’s potential for biodiversity and might threaten species in need of different types of milieu. The main purpose of this study was to investigate how important older pine trees are for biodiversity. In the Hall-Hangvar Reserve in the north-west part of Gotland, insects collected from traps showed that more species were found in old or dead trees compared to younger pine trees. A statistically significant difference was found for Coleoptera (beetles). The taxons of greatest interest for this study were Coleoptera and Hymenoptera (wasps). Certain families of Hymenoptera use ducts made by larvae from some families of Coleoptera.These larvae also serve as prey. Relevance concerning enviromental importance to species and diffrenences in inhabiting the three stages of pine trees was of importance.</p>

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