Calculation of the critical crack size for cold form rectangular hollow section tube (CRHS) under bending load at -40º C temperature

To predict the capacity of the structure or the point which is followed by instability, calculation of the critical crack size is important. Structures usually contain several cracks but not necessarily all of these cracks lead to failure or reach the critical size. So, defining the harmful cracks or the crack size which is the most leading one to failure provides criteria for structure’s capacity at elevated temperature. The scope of this thesis was to calculate fracture parameters like stress intensity factor, the J integral and plastic and ultimate capacity of the structure to estimate critical crack size for this specific structure. Several three dimensional (3D) simulations using finite element method by Ansys program and boundary element method by Frank 3D program were carried out to calculate fracture parameters and results with the aid of laboratory tests (loaddisplacement curve, the J resistance curve and yield or ultimate stress) leaded to extract critical size of the crack. Two types of the fracture which is usually affected by temperature, Elastic and Elasti-Plastic fractures were simulated by performing several linear elastic and nonlinear elastic analyses. Geometry details of the weldment; flank angle and toe radius were also studied independently to estimate the location of crack initiation and simulate stress field in early stages of crack extension in structure. In this work also overview of the structure’s capacity in room temperature (20 ºC) was studied. Comparison of the results in different temperature (20 ºC and -40 ºC) provides a threshold of the structure’s behavior within the defined range.

Makeovermani - ny form av magi?

Kirjallisuusarvostelu

Mikael Agricolan teosten kielen ala-, ylä-, ja -pää-vartaloiset adpositiot

Adpositions with the stems ala, ylä and pää in the language of Mikael Agricola’s writings The language of Mikael Agricola’s (c 1510–1557) writings represents an interesting phase in the development of the Finnish system for adpositions. In the Finnish language, the older Uralic system of postpositions has undergone expansion and a new system of prepositions has been adopted. On the other hand, the adposition system found in Agricola’s writings has also been strongly affected by foreign models, because Agricola’s texts are mainly translations of religious texts, which by and large use a word-for-word translation strategy. In the thesis, I explore Agricola’s use of adpositions; more specifically, which adpositions carry the meaning of ‘being under’ or ‘being over’ something, and in what other functions these adpositions are used. My main focus is on the semantics of the adpositions. I also study the syntactic features of adpositions and adposition structures; these are intertwined with semantics, since the meaning of adpositions is established in the adposition clause. Finally, I compare Agricola’s use of adpositions to the corresponding adpositions of present-day Finnish. Adpositions with stems ala, ylä and pää form an interesting subject for research. Their frequency in the data, however, is highly uneven. The overwhelming majority of the adpositions studied in the thesis are päälle; there are only two occurrences of adpositions with the stem ylä. Adpositions typically denote a location ‘under’ or ‘above’ something. Almost half of the adpositions, however, can be classified as semantically unmotivated and as representing a foreign model in terms of the Finnish language; they do not occur in present-day Finnish. In Agricola’s texts they act in more grammatical roles than the corresponding adpositions of present-day Finnish. In the thesis, the corresponding adpositions in the source languages are carefully analysed. All other uses of the adpositions are marginal in relation to spatial ones and those based on foreign models. The original meanings of the adpositions have not changed much since Agricola, but adpositions considered to originate from foreign models have been intentionally eliminated in presentday standard Finnish. It is also noteworthy that the system of adpositions with the stems ala, ylä and pää has changed since Agricola. His texts include the adposition ala, which corresponds to the modern adposition alle. Likewise the adposition yllä is absent in Agricola, as are the internal locative cases of the adposition pää.

Autologous Stem Cell Transplantation In Multiple Myeloma

Background. Multiple myeloma (MM) is the second most common hematologic malignancy after lymphomas In Finland: the annual incidence of MM is approximately 200. For three decades the median survival remained at 3 to 4 years from diagnosis until high-dose melphalan treatment supported by autologous stem cell transplantation (ASCT) became the standard of care for newly diagnosed MM since the mid 1990’s and the median survival increased to 5 – 6 years. This study focuses on three important aspects of ASCT, namely 1) stem cell mobilization, 2) single vs. double ASCT as initial treatment, and 3) the role of minimal residual disease (MRD) for longterm outcome. Aim. The aim of this series of studies was to evaluate the outcomes of MM patients and the ASCT procedure at the Turku University Central Hospital, Finland. First, we tried to identify which factors predict unsuccessful mobilization of autologous stem cells. Second, we compared the use of short-acting granulocyte-colony stimulating factor (GCSF) with long-acting G-CSF as mobilization agents. Third, one and two successive ASCTs were compared in 100 patients with MM. Fourth, for patients in complete response (CR) after stem cell transplantation (SCT), patient-specific probes for quantitative allele-specific oligonucleotide polymerase-chain reaction (qASO-PCR) measurements were designed to evaluate MRD and its importance for long-term outcome. Results. The quantity of previous chemotherapy and previous interferon use were significant pre-mobilization factors that predicted mobilization failure, together with some factors related to mobilization therapy itself, such as duration and degree of cytopenias and occurrence of sepsis. Short-acting and long-acting G-CSF combined with chemotherapy were comparable as stem cells mobilizers. The progression free (PFS) and overall survival (OS) tended to be longer after double ASCT than after single ASCT with a median follow-up time of 4 years, but this difference disappeared as the follow-up time increased. qASO-PCR was a good and sensitive divider of the CR patients into two prognostic groups: MRD low/negative (≤ 0.01%) and MRD high (>0.01%) groups with a significant difference in PFS and suggestively also in OS. Conclusions. When the factors prediciting a poor outcome of stem cell mobilization prevail, it is possible to identify those patients who need specific efforts to maximize the mobilization efficacy. Long-acting pegfilgrastim is a practical and effective alternative to short-acting filgrastim for mobilization therapy. There is no need to perform double ASCT on all eligible patients. MRD assessment with qASO-PCR is a sensitive method for evaluation of the depth of the CR response and can be used to predict long-term outcome after ACST.

Effects of Silica Based Biomaterials on Bone Marrow Derived Cells - Material Aspects of Bone Regeneration

Silica based biomaterials, such as melt-derived bioactive glasses and sol-gel glasses, have been used for a long time in bone healing applications because of their ability to form hydroxyapatite and to stimulate stem cell proliferation and differentiation. In this study, bone marrow derived cells were cultured with bioactive glass and sol-gel silica, and seeded into porous polymer composite scaffolds that were then implanted femorally and subcutaneously in rats to monitor their migration inside host tissue. Bone marrow derived cells were also injected intraperitoneally. Transplanted cells migrated to various tissues inside the host, including the lung, liver spleen, thymus and bone marrow. The method of transplantation affected the time frame of cell migration, with intraperitoneal injection being the fastest and femoral implantation the slowest, but not the target tissues of migration. Transplanted donor cells had a limited lifetime in the host and were later eliminated from all tested tissues. Bioactive glass, however, affected the implanted cells negatively. When it was present in the scaffold no donor cells were found in any of the tested host tissues. Bioactive glass S53P4 was found to support both osteoblastic and osteoclastic phenotype of bone marrow derived cells, but it was resistant to the resorbing effect of osteoclastic bone marrow derived cells, showing that bioactive glass is rather dissolved through physicochemical reactions than resorbed by cells. Fast-dissolving silica sol gel in microparticulate form was found to increase collagen formation by bone marrow derived cells, while slow dissolving silica microparticles enhanced their proliferation, suggesting that the dissolution rate of silica controls the response of bone marrow derived cells.

Pluripotency and genetic stability of human pluripotent stem cells

Pluripotent cells have the potential to differentiate into all somatic cell types. As the adult human body is unable to regenerate various tissues, pluripotent cells provide an attractive source for regenerative medicine. Human embryonic stem cells (hESCs) can be isolated from blastocyst stage embryos and cultured in the laboratory environment. However, their use in regenerative medicine is restricted due to problems with immunosuppression by the host and ethical legislation. Recently, a new source of pluripotent cells was established via the direct reprogramming of somatic cells. These human induced pluripotent stem cells (hiPSCs) enable the production of patient specific cell types. However, numerous challenges, such as efficient reprogramming, optimal culture, directed differentiation, genetic stability and tumor risk need to be solved before the launch of therapeutic applications. The main objective of this thesis was to understand the unique properties of human pluripotent stem cells. The specific aims were to identify novel factors involved in maintaining pluripotency, characterize the effects of low oxygen culture on hESCs, and determine the high resolution changes in hESCs and hiPSCs during culture and reprogramming. As a result, the previously uncharacterized protein L1TD1 was determined to be specific for pluripotent cells and essential for the maintenance of pluripotency. The low oxygen culture supported undifferentiated growth and affected expression of stem cell associated transcripts. High resolution screening of hESCs identified a number of culture induced copy number variations and loss of heterozygosity changes. Further, screening of hiPSCs revealed that reprogramming induces high resolution alterations. The results obtained in this thesis have important implications for stem cell and cancer biology and the therapeutic potential of pluripotent cells.

Education export as a form of knowledge transfer : The potential of Finnish education export in Chile

Knowledge transfer is a complex process. Knowledge transfer in the form of exporting education products from one system of education to another is particularly complicated, because each system has been developed in a particular context to meet the requirements seen as relevant at each time. National innovation systems are often seen to form an essential framework within which the development of a country, its economy and level of knowledge are considered and promoted. These systems are orientated towards the future, and as such they also provide a framework for the knowledge transfer related to the development of education. In the best of circumstances they are able to facilitate and boost this transfer both from the viewpoint of the provider and the recipient. The leading thought and the idea of the study is that education export is a form of knowledge transfer, which is illustrated by the existing models included. The purpose of this study is to explore, analyze and describe the factors and phenomena related to education export, and more specifically, those related to the experiences and potential of Finnish education export to Chile. For better understanding, of the multiplicity of the issue involved, the current status of education export between Finland and Chile and he existing efforts within the Finnish innovation network will be outlined as well as new forms of co-operation between Finland and Chile in educational matters explored. Several countries have started to commercialize their education system in order to establish themselves as emerging education exporters. Moreover, the demand for education reform is accurate in many developing countries. This offers a good match between Finland and Chile to be the example countries of the research. The main research findings suggest that there are several business areas in education export. These include degrees in education, training services and education technologies for example The factors that influence education export can be divided into four groups, including academic, cultural, political and economic aspects. Challenges to overcome include the lack of product or services to be sold, lack of market and cultural knowledge of the buyer country, financing and lack of suitable pricing model. National innovation systems could be seen as enabling entities for successful education export. The extensive networks that national innovation systems aim to form, could operate as a basis for joining the forces in selling knowledge as well as receiving knowledge in a constructive way.

Hakkeen kuivaus ennen varastointia ja biopolttoaineterminaalin suunnittelu

Lempäälään aiotaan rakentaa uusi kaukolämpölaitos, jossa polttoaineena käytettäisiin haketta. Nykyään Lempäälässä tuotetaan kaukolämpöä maakaasulla, jonka käyttämisestä halutaan siirtyä käyttämään lähialueilta saatavaa biopolttoainetta. Tässä työssä halutaan selvittää, mitä hyötyjä saataisiin hakkeen koneellisesta kuivauksesta. Työn toisena tavoitteena on suunnitella ja pohtia biopolttoaineterminaalin rakentamista sekä käsitellä hakkeen varastointia yleensä. Työssä tutustutaan hakkeeseen aiheesta kertovan kirjallisuuden avulla. Työssä on myös laskettu hakkeen kuivauksesta saatavia hyötyjä hakkeen lämpöarvoon sekä energiatiheyteen. Erityisesti perehdytään metsätähdehakkeeseen, rankahakkeeseen, kuorihakkeeseen sekä sahanpuruun. Laskelmien tuloksista on havaittu, että suurin hyöty hakkeen energiatiheyden parantumisessa saadaan kun hake kuivataan 35 % kosteuspitoisuuteen. Tämän jälkeen energiatiheyden paraneminen tapahtuu hitaammin. Hakkeen kuivauksesta saadaan myös muita hyötyjä kuin energiatiheyden paraneminen. Kuivan hakkeen käsittelyn ja varastoinnin on havaittu olevan vaivattomampaa kuin märän hakkeen. Biopolttoaineterminaalin ja voimalaitoksen tulisi sijaita rinnakkain, jotta hakkeen kuivauksesta saadaan mahdollisimman kustannustehokasta. Näin ollen syntyisi myös säästöjä hakkeen kuljetuksen suhteen. Biopolttoaineterminaalin rakentamista varten tarvittaisiin tilaa alustavien laskelmien perusteella noin yksi hehtaari. Työssä on myös laskettu biopolttoaineterminaalin rakentamisesta aiheutuvia kustannuksia sekä hakkeen kuljetuksesta koituvia logistiikka kustannuksia. Haketerminaalin ja voimalaitoksen sijaintia Lempäälässä on myös kartoitettu.

Regulation of self-renewal and detection of karyotypic changes of pluripotent human embryonic stem cells

Human embryonic stem cells are pluripotent cells capable of renewing themselves and differentiating to specialized cell types. Because of their unique regenerative potential, pluripotent cells offer new opportunities for disease modeling, development of regenerative therapies, and treating diseases. Before pluripotent cells can be used in any therapeutic applications, there are numerous challenges to overcome. For instance, the key regulators of pluripotency need to be clarified. In addition, long term culture of pluripotent cells is associated with the accumulation of karyotypic abnormalities, which is a concern regarding the safe use of the cells for therapeutic purposes. The goal of the work presented in this thesis was to identify new factors involved in the maintenance of pluripotency, and to further characterize molecular mechanisms of selected candidate genes. Furthermore, we aimed to set up a new method for analyzing genomic integrity of pluripotent cells. The experimental design applied in this study involved a wide range of molecular biology, genome-wide, and computational techniques to study the pluripotency of stem cells and the functions of the target genes. In collaboration with instrument and reagent company Perkin Elmer, KaryoliteTM BoBsTM was implemented for detecting karyotypic changes of pluripotent cells. Novel genes were identified that are highly and specifically expressed in hES cells. Of these genes, L1TD1 and POLR3G were chosen for further investigation. The results revealed that both of these factors are vital for the maintenance of pluripotency and self-renewal of the hESCs. KaryoliteTM BoBsTM was validated as a novel method to detect karyotypic abnormalities in pluripotent stem cells. The results presented in this thesis offer significant new information on the regulatory networks associated with pluripotency. The results will facilitate in understanding developmental and cancer biology, as well as creating stem cell based applications. KaryoliteTM BoBsTM provides rapid, high-throughput, and cost-efficient tool for screening of human pluripotent cell cultures.