The focus of this dissertation is on the development of a solid freeform fabrication (SFF) process for the design and manufacture of porous biodegradable orthopaedic implants from calcium polyphosphate (CPP). Porous CPP structures are used as bone substitutes for regenerating bone defects and/or as substrates in formation of so-called “biphasic” implants for repair of damaged osteochondral tissues. The CPP implants can be utilized in the treatment of many musculoskeletal diseases, osteochondral defects, and bone tumours while replacement of the defect site is required. In this study, the fabrication of CPP structures was developed through a powder-based SFF technique known as adhesive bonding 3D-printing. SFF is an advanced alternative to the “conventional” fabrication method consisting of gravity sintering of CPP pre-forms followed by machining to final form, as SFF enables rapid manufacturing of complex-shaped bio-structures with controlled internal architecture. To address the physical and structural properties of the porous SFF-made components, they were characterized using scanning electron microscopy, micro-CT scanning and mercury intrusion porosimetry. Specific surface area and permeability of the porous structures were also determined. Additionally, the chemical properties (crystallinity) of the specimens were identified by X-ray diffraction. The mechanical properties of the crystalline CPP material were also measured by micro- and nano-indentation. Moreover, the porous structures were tested by uniaxial and diametral mechanical compression to determine the compressive and tensile strengths, respectively. Furthermore, the effect of the stacked-layer orientation on the mechanical properties of the SFF-made constructs was investigated through the production of samples with horizontal or vertical stacked-layers. The properties of the SFF-made samples were compared with those of the conventionally-made CPP constructs. The SFF-made implants showed drastically higher compressive mechanical strength compared to the conventionally-formed samples with identical porosity. It was also shown that the orientation of the stacked-layer has substantial influence on the mechanical strengths. Moreover, this thesis examined the ability of in vitro forming of cartilaginous tissue on the SFF-made substrates where the chondrocytes cellular response to the CPP implants was evaluated histologically and biochemically. In addition, an initial in vivo assessment of the CPP structures as bone substitutes was conducted using a rabbit medial femoral site model. Significant amount of new-bone was formed within the CPP porous constructs during the 6-week implantation period demonstrating appropriate biological response of SFF-made CPP structures for bone substitute applications. Another accomplishment of this thesis was the development of a mathematical model which predicts the compact density of powder layers spread by a counter-rotating roller in the SFF technique. The results may be used in the control of the apparent density of the final implant. The potential of the developed SFF method as an efficient and reproducible technique for the production of porous CPP structures for use in orthopaedics and musculoskeletal tissue regenerative applications was concluded.

The effects of the kappa opioid agonist U-50,488 on morphine-induced condtioned place preference (CPP), locomotor activity and Fos immunoreactivity and assessed in 10-, 17- and 35-day old rats. It was predicted that kappa agonist treatment would block the unconditioned and conditioned behaviors produced by morhine (a mu opioid receptor agonist).

Viral vectors derived from mouse polyomavirus are a convenient tool for studying the targeted delivery of therapeutical agents into the cells and cellular organelles. Vectors derived from mouse polyomavirus face difficulties similar to other nanoparticles, as they often end up trapped inside an endosome where they are subsequently degraded. This diploma explored the potential of vector modifications, which have the potential to make the transport to the nucleus or cytosol more effective. This work had particularly focused on increasing the transduction efficiency by modifying particle's internally localized VP3 capsid protein with covalently bound membrane-penetrating peptides. Primary covalent genetic modification to the VP3 protein was the polyhistidine peptide KH27K. Its potential of improving the transduction effectivity was compared with two other peptide modifications - LAH4 and R8. The results of the transduction test showed that covalently bound R8 peptide had many-fold improved the transport to the nucleus when compared to the unmodified particles. The modification with LAH4 peptide had been regarded more effective only when was associated with the particles non-covalently. In such scenario the transduction efficiency rose 40-times when compared with unmodified particles. Polyhistidine...

<p>  </p> <p>The access of ring junction functionalized 5,6-hydrindanone systems has been elusive in the realm of synthetic methodology, and the functionalization of a pre-built ring system rarely explored. These 5,6-hydridanone systems are prevalent in a variety of terpenoid ring systems, especially that of steroidal molecules. Previous synthetic methods to reach these systems using a Diels-Alder cycloaddition proved to be difficult and lacked labile functional groups that would be useful for substitution after the cycloaddition. The design of the α-nitrile cyclopentenone dienophile allows for both post-cyclization adduct functionalization, as well as lowering the energy barrier of the cycloaddition itself. In this work, it is shown that the Lewis acid promoted Diels-Alder reaction with α-nitrile β-methyl cyclopentenone dienophile can be performed under standard temperatures and pressures unlike previously established methods.1 This reaction can generate four chiral centers in a single synthetic step when the starting materials are prochiral. After the generation of 5,6-hydrindanone systems, radical cleavage of the nitrile functionality also allowed for electrophile trapping at the ring junction. This radical cleavage and electrophile trapping pathway allows for functionalization of a quaternary carbon at the ring junction, a method that should be fruitful in the generation of difficult to synthesize steroidal and other terpenoid molecules.</p> <p>In the work on synthetic cell penetrating peptides, camptothecin whilst a notably effective topoisomerase I inhibitor, has never quite reached it’s potential as a therapeutic due to its poor solubility in living systems. Previously, cationic amphiphilic polyproline helices (CAPH) molecules from the Chmielewski lab have been hydrophobically functionalized through O-alkylation of hydroxyprolines at specific regions within the peptide to generate a hydrophobic face. The combination of the cationic faces and the hydrophobic face have made the CAPH molecules notably cell penetrant and tunable. With camptothecin’s notable insolubility in water, it may serve as valuable surrogate to the hydrophobic groups on CAPH molecules and allowing it to be delivered intracellularly. Using an endogenously cleavable linker, we have worked towards a CPP that acts as a drug delivery vehicle. Acting as a replacement of the hydrophobic residue of a CAPH molecule, camptothecin will be chaperoned into the cell and should be released through the action of intracellular esterases.</p>

Genetic mutations can cause a wide range of diseases, e.g. cancer. Gene therapy has the potential to alleviate or even cure these diseases. One of the many gene therapies developed so far is RNA-cleaving deoxyribozymes, short DNA oligonucleotides that specifically bind to and cleave RNA. Since the development of these synthetic catalytic oligonucleotides, the main way of determining their cleavage kinetics has been through the use of a laborious and error prone gel assay to quantify substrate and product at different time-points. We have developed two new methods for this purpose. The first one includes a fluorescent intercalating dye, PicoGreen, which has an increased fluorescence upon binding double-stranded oligonucleotides; during the course of the reaction the fluorescence intensity will decrease as the RNA is cleaved and dissociates from the deoxyribozyme. A second method was developed based on the common denominator of all nucleases, each cleavage event exposes a single phosphate of the oligonucleotide phosphate backbone; the exposed phosphate can simultaneously be released by a phosphatase and directly quantified by a fluorescent phosphate sensor. This method allows for multiple turnover kinetics of diverse types of nucleases, including deoxyribozymes and protein nucleases. The main challenge of gene therapy is often the delivery into the cell. To bypass cellular defenses researchers have used a vast number of methods; one of these are cell-penetrating peptides which can be either covalently coupled to or non-covalently complexed with a cargo to deliver it into a cell. To further evolve cell-penetrating peptides and understand how they work we developed an assay to be able to quickly screen different conditions in a high-throughput manner. A luciferase up- and downregulation experiment was used together with a reduction of the experimental time by 1 day, upscaling from 24- to 96-well plates and the cost was reduced by 95% compared to commercially available assays. In the last paper we evaluated if cell-penetrating peptides could be used to improve the uptake of an LNA oligonucleotide mimic of GRN163L, a telomerase-inhibiting oligonucleotide. The combination of cell-penetrating peptides and our mimic oligonucleotide lead to an IC50 more than 20 times lower than that of GRN163L.

Chronic pelvic pain (CPP) is defined as constant or intermittent lower, cyclical or non-cyclical abdominal pain of at least six months’ duration. In the United Kingdom, over 1 million women suffer from CPP, with an estimated annual healthcare cost above £150 million. The aetiology of CPP is unknown in up to 50% of women, and in the remainder, the symptoms of CPP is associated with endometriosis, pelvic adhesions, irritable bowel syndrome or painful bladder syndrome. CPP is often accompanied by painful periods, pain during sexual intercourse and defaecation. Fatigue, sleep disturbances and depression are also common among this group of women. CPP asserts a heavy emotional, social and economic burden. Standard treatments such as hormonal and analgesic regimens are often associated with unacceptable side effects, even if helpful for the pain, underlining an urgent need for a satisfactory treatment. The meridian balanced method (BM) electro-acupuncture (EA) treatment (acupuncture needling + traditional Chinese medicine health consultation [TCM HC]) may be effective in managing CPP symptoms. Thus, I have completed a pilot study comprising of a three-armed randomised controlled trial (RCT), using a mixed methods research (MMR) approach, to assess the feasibility of a future large-scale RCT to determine the effectiveness of the meridian BMEA treatment on CPP in women. My hypothesis is that it is feasible to conduct such a large-scale RCT for CPP in women. The primary objectives were to determine recruitment and retention rates. The secondary objectives were to evaluate the, acceptability of the methods of recruitment, randomisation, interventions and assessment tools and any signals of effectiveness of the interventions. Thirty (30) women with CPP were randomised into three groups: BMEA treatment, TCM HC, or National Health Service standard care (NHS SC) group. The effects of my interventions were assessed by validated pain, physical and emotional functioning questionnaires, completed at weeks 0, 4, 8 and 12 of the study. Semi-structured telephone interviews and focus group discussions to explore participants’ experience of the study were conducted. Of the 59 women who were referred to the study, 30 women (51%) were randomised. There was a statistically significant difference in retention rates between the three groups. The retention rates were 80% (95% CI 74-96), in the BMEA treatment group, 53 % (95% CI 36- 70) in the TCM HC group and 87% (95% CI 63-90) in the NHS SC group. (Chi-square test, p=0.08) The attendance rates of the BMEA treatment group were 90% compared to 56% in the TCM HC group. There was a statistically significant difference (Mann-Whitney test, p=0.023) in attendance between the two intervention groups. Telephone interviews regarding the acceptability of the methods of recruitment, randomisation, assessment tools and interventions were positive. No adverse effects that were directly related to BMEA treatments were reported or observed. A higher proportion of the BMEA treatment group achieved clinical significance in the VAS-pain, BPI-pain severity, interference, and sleep scores, when compared to the other two groups. Due to small sample sizes, there was insufficient power to show statistically significant difference. (Fishers Exact Test, p=1.0) Analyses of the questionnaire data per group showed statistically significant differences in the following: the BMEA treatment group experienced less in pain at weeks 4 (p=0.01) and 8 (p=0.005); less helplessness (p=0.03) and their anxiety and depression scores declined at week 4 (p=0.04). The NHS SC group also reported less pain at week 4 (p=0.04). However, this group scored higher in anxiety and depression at weeks 8 and 12 (p=0.04). No statistically significant differences were achieved between the three groups at baseline, weeks 4, 8 and 12 in all scores. The therapeutic benefits gained by the TCM HC group were less compared to those of the BMEA treatment group, but better when compared to the NHS SC group. The BMEA treatment and TCM HC groups showed lower scores in anxiety and depression while the NHS SC group showed higher scores in anxiety and depression. The NHS SC group also tended to ruminate and magnify their problems as well as feeling more helpless than the other two groups. The three key themes that emerged from thematic analysis of focus group discussions were the “whole person effects” where participants reported an improvement in pain, sleep and a general sense of wellbeing in the two intervention groups; the “experience of standard care” and “impact of living with CPP”. In conclusion, the results of my pilot study are supportive of the feasibility of a future large-scale study. There were signals of effectiveness of interventions but the sample size was too small to make a definitive conclusion.

Introdução: A Dor Pélvica Crônica (DPC) é um problema social, com alta prevalência, acometendo mulheres na idade reprodutiva. Cada vez mais salientamos a importância de investigar instrumentos apropriados para avaliação da dor, facilitando na prática clínica a escolha do melhor método que torne mais completa a avaliação de aspectos da intensidade na mensuração da dor crônica. Portanto, o objetivo deste estudo é correlacionar diferentes instrumentos de avaliação da intensidade dolorosa, a escala numérica (EN), escala visual analógica (EVA) e a algometria de pressão, nas mulheres com DPC, a fim de identificar o instrumento que melhor expressa o quadro doloroso. Métodos: foram avaliadas pelo ginecologista oitenta mulheres encaminhadas ao ambulatório do serviço de Ginecologia e Obstetrícia do Hospital de Clínicas de Porto Alegre (HCPA), trinta e três mulheres apresentaram algum aspecto dos nossos critérios de não inclusão. Selecionamos para participar do estudo quarenta e sete pacientes com DPC, sendo que vinte pacientes apresentavam endometriose diagnosticada por videolaparoscopia e vinte e sete pacientes apresentavam outras causas ginecológicas. Utilizamos no estudo um roteiro para anamnese cujos dados relacionados com a DPC foram coletados, tais como diagnóstico, tratamento, sintomatologia e locais da dor. Escores de dor foram classificados de acordo com a intensidade, através das escalas de dor (EN e EVA), instrumentos baseados no autorrelato do indivíduo e algometria de pressão, para verificar o limiar de dor à pressão das pacientes. Na análise dos dados, a concordância entre as escalas foi avaliada pelo coeficiente de correlação intraclasse (ICC) e a associação entre as escalas com o algômetro foi avaliada pelo coeficiente de correlação de Spearman, o nível de significância adotado foi de 5% (P<0,05). Resultados: As participantes do estudo tinham idade média de 38,3 ± 7,6 anos. Utilizamos o ICC para análise da correlação entre os instrumentos de relato da percepção dolorosa, ou seja, entre as EN e EVA, em relação à dor (0,992), na dismenorreia (1,00) e na dispareunia (0,996), e encontramos excelente concordância entre as escalas, com P<0,01. As associações da algometria com as escalas foram moderadas e inversas, apresentando diferenças estatisticamente significativas, quanto maior a pontuação nas escalas EN e EVA em relação à dispareunia, menores os valores no algômetro, exceto nos pontos LA1 e LA2 em ambos os lados. Também houve associação inversa das escalas EN e EVA na dismenorréia, no ponto LAB2 lado direito e associação inversa no ponto PS lado direito com a escala EVA de dor, com diferenças estatisticamente significativas. Conclusão: As escalas são instrumentos eficientes para avaliação da dor, podendo ser utilizada tanto a EN quanto a EVA na avaliação da intensidade dolorosa. Na avaliação das mulheres com DPC devemos utilizar a algometria de pressão associada à EN ou EVA, instrumentos inversamente proporcionais, confiáveis e sensíveis, tornando menos subjetiva a avaliação da dor para melhor expressar o quadro doloroso. / Introduction: The Chronic Pelvic Pain (CPP) is a social problem, with high prevalence, affecting women in reproductive age. Increasingly, has been emphasised the importance of investigating appropriate instruments for evaluation of pain in clinical practice, by facilitating the choice of the best method to make more complete the evaluation in measuring intensity aspects of chronic pain. Therefore, the objective of this study is to correlate different painful intensity assessment tools, the numeric scale (NS), visual analogue scale (VAS) and algometry pressure, in women with CPP, in order to identify the instrument that best expresses the pain. Methods: were evaluated by the gynecologist eighty women referred to the Gynecology and Obstetrics service, Clinical Hospital of Porto Alegre (HCPA), thirty three women had some aspect of our criteria for not inclusion. The study included forty seven patients, twenty patients had endometriosis diagnosed by laparoscopy and twenty seven patients had other gynecological causes. For the analyses in this study we used a road map for anamnesis whose data related to the CPP was collected, such as diagnosis, treatment, symptoms and pain locations. In addition, pain scores were classified according to intensity, through the pain scales (NS and VAS), based on self-report instruments of individual and algometry, to verify the pressure pain threshold of the patients. Statistically, the agreement between scales was assessed by intraclass correlation coefficient (ICC) and the association between the scales with the algometer were evaluated by Spearman's rank correlation coefficient, the level of significance adopted was 5% (P<0,05). Results: Study participants had an average age of 38.3 ± 7.6 years old. In the statistical analysis, we used ICC reporting instruments of perception painful I mean, between NS and VAS regarding pain (0,992), in dysmenorrhoea (1.00) and Dyspareunia (0.996), and we found excellent correlation between scales, with P<0,01. The associations of algometria with the scales were moderate and inverses, showing differences statistically significant, the higher the score NS and VAS in relation to Dyspareunia smaller values in algometer, except in points LA1 and LA2 on both sides. Indeed, there were also inverse association of scales NS and VAS on dysmenorrhea, in point LAB2 in the right side and inverse association in point PS in the right side with scale VAS of pain, with statistically significant differences. Conclusion: the scales are effective instruments for evaluation of pain, and may be used both in NS and VAS at painful intensity evaluation. In the evaluation of women with CPP should be used the algometry pressure associated with NS or VAS, instruments inversely proportional, reliable and sensitive, making less subjective pain assessment to better express the pain.

安非他命與古柯鹼皆屬心理興奮性藥物(psychostimulants)，在藥理上有很多功能相似的機制，而且兩種藥物濫用成癮的問題一直是臨床及基礎研究所關心的問題。就動物行為模式而言，安非他命與古柯鹼具有影響包括反射性及制約學習性的行為表現的效果。若針對藥物的酬賞性做探討時，制約性場地偏好行為模式的相關研究益發受到重視，本研究實驗一先針對此作業之操弄時間及環境變項做一探討，再研究安非他命與古柯鹼之作用機制。過去的研究發現，週邊注射安非他命或古柯鹼與某環境刺激配對能引發制約性引發場地偏好的傾向，但兩藥的行為現象卻對藥理的操弄呈不一致的結果，隱含兩藥背後的神經機制可能也不同。其中阿控博核是一個值得再驗證的區域。阿控博核被認為是動機系統與運動系統的介面。此部位因其解剖及生化功能的異質性，故實驗二針對其次分區進行中樞藥物注射，於是直接將安非他命(10，15μg)與古柯鹼(50，100μg)分別注射於阿控博核之次級區。結果發現安非他命直接注入阿控博核核區或古柯鹼注入阿控博核殼區可表現顯著的場地偏好效果。基於阿控博核所含有的麩胺酸神經末梢源自內側前額葉皮質，實驗三則發現安非他命或古柯鹼注入內側前額葉皮質可引發制約性場地偏好行為。實驗四將麩胺酸專屬受體抑制劑與安非他命共同注入核區或與古柯鹼共同注入殼區，結果發現不論NMDA或non-NMDA受體抑制劑均減抑了安非他命與古柯鹼注入阿控博核不同區所引發之制約性場地偏好的效果。最後實驗五利用內側前額葉遭破壞的受試，發現古柯鹼注入阿控博核殼區所引發之制約性場地偏好的效果受損，但不影響安非他命注入阿控博核核區所引發之制約性場地偏好的效果。綜觀上述結果顯示安非他命與古柯鹼的酬賞特質所引發行為的神經機制可能不同，腦中之內側前額葉皮質及阿控博核對兩藥的行為效果有不同的涉入。 / The function of the nucleus accumbens (NACC) has been suggestedto play an important role of the rewarding effects of psychostimulants.It is hypothesized that the neural substrates for amphetamine and cocaineto produce behavioral effects can be different. As conducted in Experiment 1, a conditioned place preference (CPP) task with procedures for amphetamine microinjection was established from the manipulation of conditioning environment. In considering the heterogeneity of NACC, Experiments 2 investigated the potentiality of the CPP effects after local infusion of amphetamine (10, 15 μg/site) or cocaine (50, 100 μg/site) into the core and shell subareas of NACC. Amphetamine microinjection into the NACC core significantly produced CPP, whereas such effect only appeared under treatment of the high dose of cocaine into the shell area. Lack of the CPP effects for amphetamine or cocaine infused into the boundary areas of the core and shell regions was seen in Experiment 2 (part B). In Experiment 3, the involvement of the medial prefrontal cortex (mPFC) was challenged for amphetamine and cocaine on the CPP task. Both doses of cocaine and the low dose of amphetamine locally infused in mPFC significantly produced CPP. In Experiment 4, glutamatergic NMDA receptor antagonist APV (0.5, 1 μg/site) and non-NMDA receptor antagonist CNQX (1 μg/site) significantly attenuated the CPP effects of amphetamine infused into the NACC core. This antagonism was also true for the cocaine-induced CPP in the NACC shell. These results implied that the other cortical areas can modulate such CPP effects, in particular the mPFC. In Eperiment 5, lesion of mPFC significantly inhibited the cocaine-induced CPP in the shell area but not for the amphetamine-induced CPP in the core area. Taken together, the NACC is an important neural substrate for mediating the rewarding effects for amphetamine and cocaine on the CPP task, and such effects can be dissociated as drugs locally infused into core and shell areas. Glutamatergic projections originating mPFC may provide some motivational information to the NACC. The mPFC may distinctly be involved in the motive circuit of cocaine- or amphetamine-induced CPP in the NACC. These results highlight that different processes are involved in the acquisition of CPP for microinjection of amphetamine or cocaine into the NACC subareas.

<p><p>The thesis project is accomplished during winter and spring 2008 at Karlstad University at the faculty of technology and science. The tutor at Karlstad University is Nils Hallbäck and the examiner is Hans Johansson. Rolls-Royce at Kristinehamn in Sweden is the initiator for the project. The thesis project title is design of the blade bolt joint on Kamewa CPP. CPP stands for controllable pitch propeller. The study include two main aspects which are to analyze if the blade bolt joint which is used today can be applied on a larger propeller and if there are better solutions or other possibilities to join the blade to the hub. First the classification rules of some institutes were studied to find out which limitations there are. Bolted joint has to exceed a minimum bending strength and the bolts have to be made out of steel and their strength has to be at least 10.9. Today Rolls-Royce use ten bolts per propeller, five on each side of the blade. To analyze the strength of the blade bolt joint connection a FEM and an analytic analyze were made and the results compared with each other. Two cases were examined, one for drift and two when hitting an iceberg. The results were similar to each other for FEM and the analytic analyze. At drift all bolts were under the tensile strength of 750 MPa but when using ice loads some bolts started to deform. A new concept for the bolt connection was tested. Again the stress in the bolts stayed under the tensile strength at drift but deformed when applying ice loads. A difference between analytical and FEM analysis was that the stress difference between the bolts were minor in the FEM method. Another concept was only studied with FEM and it had a geometric locking devise combined with the same blade bolt connection as Rolls-Royce use today. At drift the locking devise didn’t support the connection much but when applying ice loads less bolts started to deform and less material in the bolts reached the tensile limit. All three concepts showed stress concentrations at the first two or three threads. The differences between the three concepts weren’t that large and to get better results other possibilities have to be considered. It is important to know how much torque has to be applied on the screw to get the right amount of pretension. Three aspects to consider are to apply the torque without getting any torsion in the screw, to lower the moment with the right coating or lubricant and to avoid the stress concentrations at the threads. Superbolts and clampnuts are two possibilities to avoid torsion in the screws. By using screw thread inserts or tension optimized threads the stress in the thread gets optimized and a coating or lubricant with a low friction coefficient will lower the torque. Three possible solutions are suggested.</p></p> / <p><p>Examensarbetet har utförts på fakulteten för teknik och naturvetenskap under vintern och våren 2008 och är en kurs på 22,5 hp med kurskoden MSGC 17. Handledare på Karlstads universitet är Nils Hallbäck och examinator är Hans Johansson. Rolls-Royce i Kristinehamn är uppdragsgivaren till examensarbetet. Uppgiften är att dimensionera ett bladförband till en stor Kamewa Ulstein CP-propeller. Frågeställningen som ska besvaras är om det går att använda dagens förband och undersöka om det finns bättre alternativ eller andra lösningar på problemet. Det finns inga ritningar på den storleken av propellrar som förbandet ska göras till. Därför måste man skala upp mått från mindre propellrar. Propellerdiameter är 7,7 meter och bladet med fot väger 10 ton efter skalningen. Förbandet ska klara av DNVs (Det Norske Veritas) klassificeringskrav för böjmotstånd och förbandet dimensioneras därefter. För dagens förband behövs det mycket stora skruvar för att klara klassificeringskravet. En analytisk och en FEM-analys genomfördes för att det inte finns något material att jämföra med. Krafter som måste betraktas är centrifugalkraften, tyngdkraften, framdrivningskraften från vattnet samt en isbelastning vid kollision med ett isberg. Framdrivningskraften varierar med 20 % när propellern passerar skrovet. Resultaten från analyserna gav att dagens förband klarar belastningarna vid drift, dock att bultarna börjar deformeras vid belastning med iskraften. I den analytiska analysen antar man att alla delar (bladfot, fläns och nav) är stela och inte deformeras. Dessutom tar man inte hänsyn till böjpåkänningarna som uppstår i skruvarna. Detta tas med i FEM-analysen samt att man räknar med olinjära materialsamband. Därför uppstår det stora spänningsskillnader, upp till 210 MPa, i bultarna vid FEM-analysen vilket inte sker vid de analytiska beräkningarna. Ett antal koncept genererades och två av dessa analyserades närmare. Båda koncepten är optimerade för centrifugalkraften eftersom den utgör den största belastningen under drift om man bortser ifrån förspänningen. Koncept 1 är ett förband som består av 16 bultar per propeller med tre olika storlekar. Enligt FEM analysen fås en jämnare spänningsfördelning över skruvarna än med dagens förband, medan den analytiska metoden ger ungefär samma fördelning som vid dagens förband. Alla skruvar håller sig under sträckgränsen vid drift. Vid isbelastningen uppnås sträckgränsen i många av de mindre skruvarna och skruvarna börjar deformeras plastiskt. I detta avseende stämmer den analytiska lösningen och FEM-analysen överens. Skillnaden är att den analytiska beräkningen visar större spänningsvariation bland skruvarna dvs. att den största och minsta spänningen hos bultarna är högre än vid FEM-beräkningarna. Det andra konceptet som analyserades närmare består av en formlåsning som sitter under bladet tillsammans med samma skruvar som används vid dagens förband. Vid drift märks knappt någon skillnad. Vid isbelastningen så tar formlåsningen dock upp mer spänning och avlastar skruvarna. Färre skruvar deformeras plastiskt. Det finns möjligheter att använda sig av redan befintliga lösningar som Superbolts, clampnuts och andra verktyg. Det som är avgörande för förbandets funktion är ett korrekt åtdragningsmoment. Positivt är att samtidigt kunna förspänna skruvarna utan torsion. En lösning är att ytbehandla skruvarna med en beläggning med känd friktionskoefficient.</p><p>Tre lösningsförslag har tagits fram som ger ett bättre resultat än dagens förband.</p></p>

The thesis project is accomplished during winter and spring 2008 at Karlstad University at the faculty of technology and science. The tutor at Karlstad University is Nils Hallbäck and the examiner is Hans Johansson. Rolls-Royce at Kristinehamn in Sweden is the initiator for the project. The thesis project title is design of the blade bolt joint on Kamewa CPP. CPP stands for controllable pitch propeller. The study include two main aspects which are to analyze if the blade bolt joint which is used today can be applied on a larger propeller and if there are better solutions or other possibilities to join the blade to the hub. First the classification rules of some institutes were studied to find out which limitations there are. Bolted joint has to exceed a minimum bending strength and the bolts have to be made out of steel and their strength has to be at least 10.9. Today Rolls-Royce use ten bolts per propeller, five on each side of the blade. To analyze the strength of the blade bolt joint connection a FEM and an analytic analyze were made and the results compared with each other. Two cases were examined, one for drift and two when hitting an iceberg. The results were similar to each other for FEM and the analytic analyze. At drift all bolts were under the tensile strength of 750 MPa but when using ice loads some bolts started to deform. A new concept for the bolt connection was tested. Again the stress in the bolts stayed under the tensile strength at drift but deformed when applying ice loads. A difference between analytical and FEM analysis was that the stress difference between the bolts were minor in the FEM method. Another concept was only studied with FEM and it had a geometric locking devise combined with the same blade bolt connection as Rolls-Royce use today. At drift the locking devise didn’t support the connection much but when applying ice loads less bolts started to deform and less material in the bolts reached the tensile limit. All three concepts showed stress concentrations at the first two or three threads. The differences between the three concepts weren’t that large and to get better results other possibilities have to be considered. It is important to know how much torque has to be applied on the screw to get the right amount of pretension. Three aspects to consider are to apply the torque without getting any torsion in the screw, to lower the moment with the right coating or lubricant and to avoid the stress concentrations at the threads. Superbolts and clampnuts are two possibilities to avoid torsion in the screws. By using screw thread inserts or tension optimized threads the stress in the thread gets optimized and a coating or lubricant with a low friction coefficient will lower the torque. Three possible solutions are suggested. / Examensarbetet har utförts på fakulteten för teknik och naturvetenskap under vintern och våren 2008 och är en kurs på 22,5 hp med kurskoden MSGC 17. Handledare på Karlstads universitet är Nils Hallbäck och examinator är Hans Johansson. Rolls-Royce i Kristinehamn är uppdragsgivaren till examensarbetet. Uppgiften är att dimensionera ett bladförband till en stor Kamewa Ulstein CP-propeller. Frågeställningen som ska besvaras är om det går att använda dagens förband och undersöka om det finns bättre alternativ eller andra lösningar på problemet. Det finns inga ritningar på den storleken av propellrar som förbandet ska göras till. Därför måste man skala upp mått från mindre propellrar. Propellerdiameter är 7,7 meter och bladet med fot väger 10 ton efter skalningen. Förbandet ska klara av DNVs (Det Norske Veritas) klassificeringskrav för böjmotstånd och förbandet dimensioneras därefter. För dagens förband behövs det mycket stora skruvar för att klara klassificeringskravet. En analytisk och en FEM-analys genomfördes för att det inte finns något material att jämföra med. Krafter som måste betraktas är centrifugalkraften, tyngdkraften, framdrivningskraften från vattnet samt en isbelastning vid kollision med ett isberg. Framdrivningskraften varierar med 20 % när propellern passerar skrovet. Resultaten från analyserna gav att dagens förband klarar belastningarna vid drift, dock att bultarna börjar deformeras vid belastning med iskraften. I den analytiska analysen antar man att alla delar (bladfot, fläns och nav) är stela och inte deformeras. Dessutom tar man inte hänsyn till böjpåkänningarna som uppstår i skruvarna. Detta tas med i FEM-analysen samt att man räknar med olinjära materialsamband. Därför uppstår det stora spänningsskillnader, upp till 210 MPa, i bultarna vid FEM-analysen vilket inte sker vid de analytiska beräkningarna. Ett antal koncept genererades och två av dessa analyserades närmare. Båda koncepten är optimerade för centrifugalkraften eftersom den utgör den största belastningen under drift om man bortser ifrån förspänningen. Koncept 1 är ett förband som består av 16 bultar per propeller med tre olika storlekar. Enligt FEM analysen fås en jämnare spänningsfördelning över skruvarna än med dagens förband, medan den analytiska metoden ger ungefär samma fördelning som vid dagens förband. Alla skruvar håller sig under sträckgränsen vid drift. Vid isbelastningen uppnås sträckgränsen i många av de mindre skruvarna och skruvarna börjar deformeras plastiskt. I detta avseende stämmer den analytiska lösningen och FEM-analysen överens. Skillnaden är att den analytiska beräkningen visar större spänningsvariation bland skruvarna dvs. att den största och minsta spänningen hos bultarna är högre än vid FEM-beräkningarna. Det andra konceptet som analyserades närmare består av en formlåsning som sitter under bladet tillsammans med samma skruvar som används vid dagens förband. Vid drift märks knappt någon skillnad. Vid isbelastningen så tar formlåsningen dock upp mer spänning och avlastar skruvarna. Färre skruvar deformeras plastiskt. Det finns möjligheter att använda sig av redan befintliga lösningar som Superbolts, clampnuts och andra verktyg. Det som är avgörande för förbandets funktion är ett korrekt åtdragningsmoment. Positivt är att samtidigt kunna förspänna skruvarna utan torsion. En lösning är att ytbehandla skruvarna med en beläggning med känd friktionskoefficient. Tre lösningsförslag har tagits fram som ger ett bättre resultat än dagens förband.