Atualmente a área de saúde vem buscando auxílio na engenharia para a contribuição no estudo e confecção de próteses para casos específicos de fraturas ou doenças ósseas. Com o avanço da tecnologia surgiram processos de manufatura que tornam possível a fabricação de próteses personalizadas. Uma dessas tecnologias é a manufatura aditiva. O grande desafio no momento está na fabricação de próteses por manufatura aditiva que combinem desempenho biomecânico e resistência estrutural. Nesse contexto, o objetivo deste trabalho é desenvolver elementos de fixação, especificamente âncoras de sutura de polímeros PEEK e PEKK, considerando seus requisitos estruturais através de simulações pelo método dos elementos finitos, e considerando que sejam fabricadas através de processos de manufatura aditiva. Este desenvolvimento permitirá a substituição de âncoras de sutura de liga de titânio, hoje largamente empregadas pelos cirurgiões, por âncoras de sutura de polímeros biocompatíveis, o que possibilitará que estes polímeros sejam absorvidos pelo corpo humano em curto e médio prazo, permitindo a completa restituição do osso afetado, melhorando a qualidade de vida do paciente pós-cirurgia. Os resultados obtidos neste trabalho indicam que a técnica poderá resultar em próteses com a biocompatibilidade desejada e resistência mecânica adequada. Próteses permanentes (articulações) ou provisórias (âncoras de sutura) seriam um dos critérios para a escolha do material a ser utilizado, absorvível ou não pelo corpo humano. / Nowadays medicine is searching assistance from engineering that may contribute in studies and confection of prothesis to specific cases of fractures and bone diseases. With the advance of technology new processes of manufacture were risen, making possible the confection of personalized prothesis. The biggest challenge of the moment is in the manufacture of additive prothesis that can combine biomechanics performance and structural resistance. In this context, the objective of this dissertation is to develop PEEK and PEKK polymer suture anchors, considering its structural requirements, taking into account their mechanical strength, through simulation by the finite element method, and considering additive manufacturing processes. This development will allow the replacement of titanium alloy suture anchors, now widely used by surgeons by suture anchors of biocompatible polymers, which enable these polymers to be absorbed by the human body in the short and medium term, allowing full regeneration of affected bone, improving the quality of life of the patient. The results of this study indicate that the technique could result in prosthesis with the desired biocompatibility and adequate mechanical strength. Permanent prosthesis (joints) or temporary (suture anchors) would be one of the criteria for the choice of material to be used, absorbable or non absorbable by the human body.

Selective electron beam melting (SEBM) is a promising powder bed Additive Manufacturing technique for near-net-shape manufacture of high-value titanium components. An extensive research program has been carried out to characterise in 3D the size, volume fraction, and spatial distribution of the pores in model samples, using X-ray computed tomography (XCT), and correlate them to the SEBM process variables. The average volume fraction of the pores (97.5 %) where fatigue cracks would initiate based on the relative stress intensity factor of all the pores. In contrast, crack growth was found to be insensitive to porosity, which was attributed to the much higher stress concentration generated by the crack in comparison to the pores. Some crack diversion was associated with the local microstructure, with prior β grain boundaries often coincident with crack diversion.

A processing procedure for the manufacture of directly acidified cottage cheese curd from 16% total solids ultrafiltered retentate was developed. The effects of preacidification of skim milk before ultrafiltration and heat treatment of retentate were investigated to improve the functional and sensory qualities of retentate curd. Retentate directly acidified with phosphoric acid and glucono-delta-lactone to pH 4.7 formed a dense, rubbery curd that could not be handled well in a vat. A heat treatment of 71.1°C for 30 min applied to the retentate resulted in a curd with acceptable handling properties. However, this heat treatment caused the curd to shift in pH, become translucent in appearance, and have a pasty texture. Preacidification of the skim milk to pH 5.8 12 h prior to ultrafiltration, and a less severe heat treatment of 71.1°C for 6 min made a stable curd with good sensory quality. A 3 x 4 x 3 randomized split block design experiment was done to test the effects of preacidification and heat treatment on the properties of retentate curd. Skim milk was pasteurized at 62.8°C for 30 min and split into three lots which were unacidified, phosphoric acid added to pH 6.2, and phosphoric acid added to pH 5.85. The three lots of skim milk were ultrafiltered at 54.4°C to 16% total solids. Each lot was divided into four treatments which were unheated, heated to 71.1°C for 7 s, 76.7°C for 7 s, and 82.2°C for 7 s. Each vat was replicated three times. Cottage cheese pH, total solids, and six sensory attributes were measured. Finished cottage cheeses were evaluated by an expert panel of five judges. Total solids, protein content, and fines content of the whey were also measured. Preacidification treatment at pH 6.2 enhanced curd structure, which increased solids recovery, reduced fines, and improved curd appearance, firmness, and texture. Heat treatments caused softening of the curd and increased moisture content in the curd. Excessive heat treatment caused shattering, fines, and mealiness. The best curd from the experiment was produced from pH 6.2 retentate heat treated at 71.1°C for 7 s. Whey proteins decreased in wheys from retentates heat treated at 76.7°C for 7 sand 82.2°C for 7 s. The effects of heat treatment were more pronounced with increasing acidification.

Danish type swiss cheese has the characteristic "eye" of a regular swiss cheese and is similar in texture. The flavor is milder and has a softer body. Because of its milder flavor and softer body it is of interest for consumption. Because it cures faster than swiss cheese it has the added advantage of cutting down curing cost and thus requires a shorter time to reach the consumers. Another advantage is that it is made in small loaves or wheels which make for better handling, for it can be sold in both wholes ale and retail establishments without cutting before wrapping. Still another advantage of Danish type swiss cheese is that small equipment needed which is also adapted to manufacturing of cheddar cheese. The problem was to make better Danish type swiss cheese by applying different types and amounts of starters using Streptococcus lactis with a mixture of (1) Streptococcus thermophilus and (2) Lactobacillus bulgaricus and also to find the best combination of these bacilli and cocci. The influence of warm room temperature upon the eye formation and body and texture was studied. The Cheese was held in brine solution for different lengths of time to find the most effective salt concentration. Different temperatures were maintained in a warm room to find out which temperature was best for a higher quality of cheese. A pancreatic enzyme was added in different amounts to a few lots of milk before pasteurization, to find out whether it affects the body and texture and reduce the curing time. Pure trypsin was used in one lot to determine its influence on the quality of cheese.

The effects of whey-based and milk -based starter media, and low concentrations (0.02% each) of citrate, phosphate and calcium upon various milk coagulation properties were measured. Samples inoculated with milk-based starter medium had shorter coagulation times, faster rate of curd formation, and greater final curd firmness than those inoculated with externally neutralized whey-based starter. Starter medium treatment was statistically interacted with calcium for coagulation time and rate of curd formation. Citrate addition caused longer coagulation times, slower rates of curd formation, and weaker final coagula. Citrate interacted with calcium and phosphate for several of the parameters measured. Addition of phosphate did not affect any of the measured parameters but was involved in several significant two-factor interactions as was calcium addition.

The purpose of this project was to initiate development of a nonrefrigerated dairy dessert product. Milk was concentrated by pressure-driven filtration and then sterilized using ultra-high temperature (UHT) processing. Following sterilization, samples were aseptically inoculated with rennet to coagulate the milk, which was then stored at room temperature. These processing steps produced a dairy dessert that did not require refrigeration. I investigated the influence of total solids, milk fat, rennet dosage, storage temperature, and storage time on curd firmness and syneresis. I investigated the effect on curd firmness and syneresis of giving the concentrate a heat treatment prior to UHT processing. Chocolate and vanilla dairy desserts were prepared, and a taste panel was conducted to compare the dairy dessert with a ready-to- eat starch-based pudding. Milk concentrate obtained by reverse osmosis did not form a gel, whereas concentrate obtained by ultrafiltration did gel. Increasing the solids content of the milk concentrate increased curd firmness, but increasing the fat content of the concentrate decreased curd firmness. Curd firmness and syneresis increased as the concentration of rennet was increased. Products stored at 21°C yielded firmer gels with more syneresis than products stored at 4°C. Moreover, products stored for longer periods of time produced firmer gels and greater amounts of syneresis. Concentrate that received a batch heat treatment prior to sterilization reduced syneresis. The addition of cocoa to the concentrate inhibited coagulation. Taste panelists preferred the commercial pudding over the dairy

A Spiral Plater and a Microtiter system were used to isolate and evaluate cultures for a paired strain culture program. Bacteriophage and temperature sensitivity data of 43 Streptococcus cremoris strains were introduced into a computer cluster program to pair the least similar strains. Selected pairs were challenged with phage. Resistant mutants were developed. Characteristics of proteinase positive and proteinase negative variants were examined. Proteinase positive isolates produced more changes in pH, cell mass and more generations in milk than their counter-parts. Paired proteinase negative cultures produced more change in pH and cell mass and more generations in milk than single strains. Whey based medium under pH control was superior to commercial internal pH control medium for proteinase negative culture propagation. Proteinase negative isolates achieved 90% of the cell mass obtained by their counterparts in nonfat dry milk-yeast medium. Proteinase negative starter culture endured significantly higher phage titers than proteinase positive cells. Proteinase negative variants sustained activity comparable with phage-free controls when challenged for seven cycles with high phage titers. Proteinase positive cells had impaired activity after the second cycle. Pairing of proteinase positive strains was advantageous for phage protection. Erythromycin, streptomycin and penicillin adversely affected the activity of both cell types, yet proteinase positive cells were significantly more inhibited. Pairing neither variant enhanced activity. Cheddar cheese was exclusively manufactured with 2% inoculum of proteinase negative cultures compared to 1.5% usage of the proteinase positive paired strains. Cheese quality and cheese making times were normal. Over 4200 consecutive vats of Cheddar cheese were made in 1982 employing one pair of proteinase positive culture. Acid control and cheese quality were improved. The cheese making times were more uniform. Smaller inocula volumes could successfully be used for bulk starter in cheese plants utilizing pH controlled starter propagation. A needle/syringe system for inoculating starter tanks provided better protection against contamination during inoculation.

The aim of the study in this thesis was to assess the stability of the mycotoxin, cyclopiazonic acid (CPA) in milk and dairy products processed from contaminated milk. A method was developed to detect CPA in milk and milk products using micellar electrokinetic capillary chromatography (MEKC), a technique of capillary electrophoresis (CE), which was rapid and non-labour-intensive. The quantifying efficiency of CE in detecting CPA was compared to Reverse Phase Liquid Chromatography. Heat-stability of CPA in milk was assessed under different conditions. A longer heat treatment of 60 degrees centigrade for 30 minutes led to a 10% decrease in the level of CPA. The results from this thesis demonstrate that CPA in milk at concentrations found in naturally contaminated milk could not be eliminated by the heat-treatment during milk processing, storage, processing and manufacture of dairy products. Occurrence of CPA in cheese curd, butter or cream following manufacture with contaminated milk was demonstrated. CPA is left in milk despite UV-visible radiation treatment with or without hydrogen peroxide and/or riboflavin. Chemical treatment, which is capable of completely eliminating CPA, is prohibited and impractical to use for milk treatment. Stability of CPA in milk and milk products confirms the potential of the toxin to reach consumers of dairy products. / Doctor of Philosophy (PhD)

Buildings have a significant impact on the environment due to the energy required for the manufacture of construction materials. The method of assessing the energy embodied in a product is known as energy analysis. Detailed office building embodied energy case studies are very rare. However, there is evidence to suggest that the energy requirements for the construction phase of commercial buildings, including the energy embodied in materials, is a significant component of the life cycle energy requirements. This thesis sets out to examine the current state of energy analysis, determine the national average energy intensities < i.e. embodied energy rates < for building materials and assess the significance of using national average energy intensities for the energy analysis of a case study office building. Likely ranges of variation in the building material embodied energy rates from the national averages are estimated and the resulting distribution for total embodied energy in the case study building simulated. Strategies for improving the energy analysis methods and data are suggested. Detailed energy analysis is shown to be a useful indicative method of quantifying the energy required for the construction of buildings.

The steel industry is the foundation that country marches toward modern of development of civilization. According to the International Iron and Steel Institute (IISI) has announced that world crude steel output reached 1,239.5 million metric tons for the year 2006. In 1996, Mainland China produced 101.2 million metric ton of crude steel. By 2001 this had risen to 150.9 million metric ton, an increase of 49.1%. In 2006, China produced 418.8 million metric ton of crude steel, an increase of 313.8% in just ten years. China¡¦s share of world crude steel production has also increased exponentially. In 1996, China became the largest steel producing country in the world. China remains the largest single market and the strongest growth area. Steel use will increase by 13% in 2007 followed by another 10% in 2008 taking the total to 443 million ton by 35% of the world total. Subject that several important environments of steel marketing change, While China poses a severe threat to Taiwan in the Steel market, Taiwanese Steel manufacturers have to move to higher ground ahead of the rising tide of mainland competition. Grounded Theory (GT) is a research method most often associated with the social sciences, (Glaser & Strauss, 1967). Thereafter Strauss in 1990 published Basics of Qualitative Research: Grounded Theory Procedures and Techniques together with Juliet Corbin. Grounded theory was developed as a systematic methodology, and its name underscores the generation of theory from data. When the principles of grounded theory are followed, a researcher using this approach will formulate a theory, either substantive (setting specific) or formal, about the phenomena they are studying that can be evaluated. To research and investigate the changing of supply-chain by interviewing decisive persons in the business, its purpose is to make this thesis more deliberate in study structure and procedures and operational logic. This research can be classified into four main groups, such as raw material suppliers,horizontal competitor,down-stream user and co-opetition(co-operation and competition). The iron and steel industry is combined with four groups, this thesis focus on iron and steel producers. Taiwanese steel industry was forced to face several critical issues from market changing in Mainland China. 1. The industrial down-streamers in Taiwan move to Mainland China. 2.The developments of upper-streamers in China that brings an extra option for purchasing raw material. 3.An increasing stress comes from excess of new established steel companies in Mainland China. 4.The lower- cost substitutes in China invade worldwide steel market. But under the special political situation and common in language and culture, both Taiwan and China industries could have more strategically options in cooperation or competition. It is influencing the key element that this research is probing into China's Mainland and interacting with steel industry of Taiwan, utilize and take Grounded Theoretical research, sum up 129 open coding altogether , sum up 14 axial coding and five selective coding progressively . In order to understand the key elements of the steel industries of both sides of Taiwan Strait.