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Design guidelines for a digital information exchange system
(2024) Nyborg, Nora; Chalmers tekniska högskola / Institutionen för industri- och materialvetenskap; Chalmers University of Technology / Department of Industrial and Materials Science; Rexfelt, Oskar; Eriksson, Siw
In the public healthcare sector of Västra Götalandsregionen (VGR), there are hundreds of ongoing innovation projects. These projects form the foundation for innovation work in the region. Besides the members of innovation projects, several other actors are involved in the innovation activity of VGR. These are for example innovation leaders, innovation coaches, innovation managers, heads of (medical) departments, support functions and people at other strategic positions. An obstacle for all these actors, including members of innovation projects, is the difficulty to access information about all the innovation projects that are or have been conducted in the sector, which complicates their work in various ways. The aim of this study was to explore the needs of each user group regarding accessing and contributing to collective information about innovation projects in the healthcare sector of VGR. The objective was to design a concept of how to meet these needs. The research study undertook an exploratory approach, including a user and context study comprising of 20 interviews, one focus groups and two surveys. Data from these activities created the foundation for mapping experiences and needs of each user group, which formed the basis for the design concept. Three design goals for a digital information exchange system were stated, based on identified core needs of the user groups. These were: • Facilitate for the user in finding projects that are potentially useful to know about in their innovation activities. • Contribute to lowering the barrier for innovators to interact and share experiences with each other. • Provide an overview of innovation projects with the purpose to facilitate leading and strategic work. The design concept developed in this study consists of visualised design guidelines for a digital information exchange system. The system comprises three parts, each serving one of the design goals. Main features were outlined for each system part, along with system user processes for to each user group
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Effects of Heat Treatment on Residual Stresses in Additive Manufacturing
Kristensen, Rasmus; Chalmers tekniska högskola / Institutionen för industri- och materialvetenskap; Chalmers University of Technology / Department of Industrial and Materials Science; Hryha , Eduard; Karslsson , Henrik; Alkaisee, Rasha
Metal additive manufacturing (AM) is constantly developing and expanding into new segments. The automotive industry has so far not implemented AM to any larger extent. One reason is the relatively high cost of AM-components, but mainly due to the materials that are available is not used to a larger extent within the automotive sector e.g. titanium and stainless steel. Powder Bed Fusion–Laser Beam (PBF– LB), the most developed metal AM-method had, until recently, a limited range of materials available. However, recently several low-alloyed carbon-containing steels, that are commonly used in vehicles and machined components have been developed. One issue with increased carbon content is that the material has shown to be difficult to manufacture with PBF–LB. Moreover, heat treatment and its influence on residual stresses, microstructure and hardness are not yet known. This thesis focuses on the residual stresses and how they are affected by the heat treatment on samples printed in a low alloy medium carbon steel, 42CrMo4 (AISI 4140). The heat treatments applied in this thesis were not intended to be optimised for 42CrMo4, but rather investigate a more industrial approach using relatively standard heat treatment cycles. After analysing the different heat treated samples it was found that in a regular quench and temper cycle, the parts achieved similar hardness as conventionally manufactured 42CrMo4 using the same heat treatment. Samples exposed to a direct temper cycle, hence just tempered as-printed, showed promising results in terms of residual stresses. This knowledge may serve as a basis to further research and development of heat treatment cycles to better utilise 42CrMo4 steels in the automotive sector
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A Modular Toolkit to Enable Intein-mediated Enzyme Fusions
(2024) Storm, Linus; Chalmers tekniska högskola / Institutionen för life sciences; Chalmers University of Technology / Department of Life Sciences; Larsbrink, Johan; Widén, Tove
In second generation biorefineries, lignocellulosic biomass is fermented by microbes to higher-value products. Hydrolysis of the substrate is necessary to break it into fragments that the microbes can utilize. Enzymatic hydrolysis is often preferred, but a bottleneck is the high costs of enzyme cocktails since lignocellulosic polymers require several types of enzymes to be degraded. Fusion enzymes have been produced to increase conversation rates, but the methods for creating them are either complex or limited. This project aimed to circumvent some of these limitations by creating a modular toolkit to produce any fusion enzymes, where the fusion is split intein-mediated in vitro. For evaluation of the toolkit, an α-xylosidase (BoGH3B) and a β-glucosidase (BoGH31A) involved in xyloglucan (XyG) degradation, were chosen. The toolkit was developed to completion and consists of eight types of parts, excluding the protein of interest. Three assemblies were confirmed by sequencing, proving that the toolkit works. Aside from the toolkit-mediated assemblies, the enzymes on their own were expressed and tested in different combinations for XyG degradation. This was done to compare with the split intein-fused enzymes. However, when it came to expressing the protein assemblies the yield was low, and no fusion could be observed. Thus, the possibly synergistic effect of fusing BoGH3B and BoGH31A could not be investigated. A lot of research is still needed to determine the usefulness of split inteins for creating enzyme fusions. For future work, some experiments need redoing, and new experiments with different linkers and configurations of the assemblies could be performed.
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Exploring the Role of the ATRX Gene in High-Risk Neuroblastoma via Genome Engineering Techniques
(2023) Jafargholizadeh, Setareh; Chalmers tekniska högskola / Institutionen för life sciences; Chalmers University of Technology / Department of Life Sciences; Nygård, Yvonne; Mondal, Tanmoy
Neuroblastoma (NB) is a rare but aggressive pediatric cancer originating form the embryonic neural crest cells. Abnormal telomere maintenance has been implicated as a major cause of high-risk neuroblastoma, with a subset of tumors following the Alternative Lengthening of Telomere positive (ALT+) pathway. ALT+ tumors are difficult to treat due to their resistance to therapy. The exact cause of NB remains unclear, but recent research suggests genetic mutations as a possible cause, particularly mutations in the ATRX gene observed in ALT+ NB patients. This study focuses on understanding the role of the ATRX gene, in promoting ALT+ neuroblastoma. To investigate this, a dual approach was utilized, involving CRISPR/Cas9 technology for complete ATRX knockout and lentiviral shRNA silencing to reduce ATRX expression. The gene expression of ATRX has been successfully downregulated, but the successful knockout of ATRX could not be verified using CRISPR/Cas9 methods. Hence, additional validation is necessary to assess the impact of ATRX expression on ALT+ and to develop more effective strategies for addressing this subgroup of high-risk neuroblastoma (NB).
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Biodiversity Impact Assessment of Conventional and Organic Cotton A Comparison Using Three Different Biodiversity Quantification Models in LCA
(2024) Dellås, Stina; Chalmers tekniska högskola / Institutionen för teknikens ekonomi och organisation; Chalmers University of Technology / Department of Technology Management and Economics; Svanström, Magdalena; Palme, Ulrika
Anthropogenic activities have led to a decline of nature’s ecosystems and biodiversity. The textile industry has contributed to this, especially through conventional cotton fiber production. Acknowledging humans’ impact on biodiversity and the industries contributing, there is a need for established models to quantify biodiversity impacts to enhance transparency in the supply chain for mitigation and responsible consumption, aligning with global efforts for biodiversity conservation. This study aimed to examine the cotton cultivation process and its impacts on biodiversity. This was done through a life cycle assessment (LCA) that compared conventional and organic cotton cultivation in Turkey. Additionally, three different impact assessment methods were used and compared to establish aspects of the models important to capture biodiversity loss and how the models can be developed. The models were ReCiPe2016, a widely applied model that covers multiple impacts and biodiversity damage pathways, and two models measuring biodiversity land use impacts, Chaudhary & Brooks (C&B) that factors in levels of land use intensity, and the Habitat Fragmentation model (HF) that includes impacts from fragmentation. The results show that the cumulative impact assessed by ReCiPe2016 revealed a greater environmental impact for conventional cotton. Land use significantly affects both systems, with organic cotton showing a larger impact. The conventional cotton production showed a higher impact from toxicity, climate change, and water use, highlighting concerns about fertilization production, use, and irrigation. Despite land use intensity considerations in C&B, the yield difference remains a crucial factor. The study suggests the need for additional models considering ecosystem multifunctionality to address biodiversity impacts between organic and conventional agriculture. Following the results from the HF model, it is proposed to examine fragmentation effects as an attribute of land use intensity. Integrating models like C&B and HF into operational models is crucial for industry and research, promoting responsible and sustainable practices to ensure comprehensive biodiversity impact coverage in life cycle assessments.