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1.	Andersson, Ulrika, et al. (författare) A comprehensive study of the association between the EGFR and ERBB2 genes and glioma risk 2010 Ingår i: Acta Oncologica. - : Informa Healthcare. - 0284-186X .- 1651-226X. ; 12, s. 17-17 Tidskriftsartikel (refereegranskat)abstract Glioma is the most common type of adult brain tumor and glioblastoma, its most aggressive form, has a dismal prognosis. Receptor tyrosine kinases such as the epidermal growth factor receptor (EGFR, ERBB2, ERBB3, ERBB4) family, and the vascular endothelial growth factor receptor (VEGFR), play a central role in tumor progression. We investigated the genetic variants of EGFR, ERBB2, VEGFR and their ligands, EGF and VEGF on glioma and glioblastoma risk. In addition, we evaluated the association of genetic variants of a newly discovered family of genes known to interact with EGFR: LRIG2 and LRIG3 with glioma and glioblastoma risk. Methods. We analyzed 191 tag single nucleotide polymorphisms (SNPs) capturing all common genetic variation of EGF, EGFR, ERBB2, LRIG2, LRIG3, VEGF and VEGFR2 genes. Material from four case-control studies with 725 glioma patients (329 of who were glioblastoma patients) and their 1 610 controls was used. Haplotype analyses were conducted using SAS/Genetics software. Results. Fourteen of the SNPs were significantly associated with glioma risk at p< 0.05, and 17 of the SNPs were significantly associated with glioblastoma risk at p< 0.05. In addition, we found that one EGFR haplotype was related to increased glioblastoma risk at p=0.009, Odds Ratio [OR] = 1.67 (95% confidence interval (CI): 1.14, 2.45). The Bonferroni correction made all p-values non-significant. One SNP, rs4947986 next to the intron/exon boundary of exon 7 in EGFR, was validated in an independent data set of 713 glioblastoma and 2 236 controls, [OR] = 1.42 (95% CI: 1.06,1.91). Discussion. Previous studies show that regulation of the EGFR pathway plays a role in glioma progression but the present study is the first to find that certain genotypes of the EGFR gene may be related to glioblastoma risk. Further studies are required to reinvestigate these findings and evaluate the functional significance.
2.	Chopin, Thierry, et al. (författare) Deep-ocean seaweed dumping for carbon sequestration: Questionable, risky, and not the best use of valuable biomass 2024 Ingår i: One Earth. - : Elsevier BV. - 2590-3330 .- 2590-3322. ; 7:3, s. 359-364 Tidskriftsartikel (refereegranskat)abstract Deep-ocean seaweed dumping is not an ecological, economical, or ethical answer to climate-change mitigation via carbon “sequestration.” Without sound science and sufficient knowledge on impacts to these fragile ecosystems, it distracts from more rational and effective blue-carbon interventions. We call for a moratorium on sinking seaweeds to deep-ocean ecosystems until its efficacy is established, and there is robust, evidence-based assessment of its environmental, economic, and societal sustainability.
3.	Dahlin, Johan (författare) Sequential Monte Carlo for inference in nonlinear state space models 2014 Licentiatavhandling (övrigt vetenskapligt/konstnärligt)abstract Nonlinear state space models (SSMs) are a useful class of models to describe many different kinds of systems. Some examples of its applications are to model; the volatility in financial markets, the number of infected persons during an influenza epidemic and the annual number of major earthquakes around the world. In this thesis, we are concerned with state inference, parameter inference and input design for nonlinear SSMs based on sequential Monte Carlo (SMC) methods.The state inference problem consists of estimating some latent variable that is not directly observable in the output from the system. The parameter inference problem is concerned with fitting a pre-specified model structure to the observed output from the system. In input design, we are interested in constructing an input to the system, which maximises the information that is available about the parameters in the system output. All of these problems are analytically intractable for nonlinear SSMs. Instead, we make use of SMC to approximate the solution to the state inference problem and to solve the input design problem. Furthermore, we make use of Markov chain Monte Carlo (MCMC) and Bayesian optimisation (BO) to solve the parameter inference problem.In this thesis, we propose new methods for parameter inference in SSMs using both Bayesian and maximum likelihood inference. More specifically, we propose a new proposal for the particle Metropolis-Hastings algorithm, which includes gradient and Hessian information about the target distribution. We demonstrate that the use of this proposal can reduce the length of the burn-in phase and improve the mixing of the Markov chain.Furthermore, we develop a novel parameter inference method based on the combination of BO and SMC. We demonstrate that this method requires a relatively small amount of samples from the analytically intractable likelihood, which are computationally costly to obtain. Therefore, it could be a good alternative to other optimisation based parameter inference methods. The proposed BO and SMC combination is also extended for parameter inference in nonlinear SSMs with intractable likelihoods using approximate Bayesian computations. This method is used for parameter inference in a stochastic volatility model with -stable returns using real-world financial data.Finally, we develop a novel method for input design in nonlinear SSMs which makes use of SMC methods to estimate the expected information matrix. This information is used in combination with graph theory and convex optimisation to estimate optimal inputs with amplitude constraints. We also consider parameter estimation in ARX models with Student-t innovations and unknown model orders. Two different algorithms are used for this inference: reversible Jump Markov chain Monte Carlo and Gibbs sampling with sparseness priors. These methods are used to model real-world EEG data with promising results.
4.	Duan, Shanghong, 1992, et al. (författare) BUILDING AND CHARACTERIZATION OF SYMMETRIC STRUCTURAL BATTERY 2022 Ingår i: ECCM 2022 - Proceedings of the 20th European Conference on Composite Materials: Composites Meet Sustainability. ; 3, s. 1169-1174 Konferensbidrag (refereegranskat)abstract Recently, a structural battery with multifunctional carbon fibre anode has been reported. The energy density of active material is not fully extracted due to the low ionic conductivity inside the battery. To identify the main region that attributes to the low ion transportation, we assemble a symmetric structural battery with one anode layer in the centre sandwiched between two cathode layers. Such a design can also be treated as a combination of two asymmetric batteries with one full thickness cathode layer plus one half thickness anode layer. Thus, the travelled distance of lithium ions is shortened only in the anode part. It is found that the area energy density of the symmetric structural battery is doubled compared to a reference asymmetric battery. Thus, the additional cathode layer activates the double amount of carbon fibres in the anode. A plausible reason is that only the carbon fibres next to the separator is activated in the battery.
5.	Eriksson, Jonny, et al. (författare) Enzymatic degradation of model cellulose films 2005 Ingår i: Journal of Colloid and Interface Science. - : Elsevier BV. - 1095-7103 .- 0021-9797. ; 284:1, s. 99-106 Tidskriftsartikel (refereegranskat)abstract Enzymatic degradation of model cellulose films prepared by a spin-coating technique was investigated by ellipsometry. The cellulose films were prior to degradation characterized by ellipsometry, contact angle measurements, ESCA (electron spectroscopy for chemical analysis) and AFM (atomic force microscopy). At enzyme addition to preformed cellulose films an initial adsorption was observed, which was followed by a total interfacial mass decrease due to enzymatic degradation of the cellulose films. The degradation rate was found to be constant during an extended time of hours, whereafter the degradation leveled off. In parallel to the decreased interfacial mass, the cellulose degradation resulted in a thinner and more dilute interfacial film. At long degradation times, however, there was an expansion of the cellulose film. The enzyme concentration affected the degradation rate significantly, with a faster degradation at a higher enzyme concentration. The effects of pH, temperature, ionic strength and stirring rate in the cuvette were also investigated. (c) 2004 Elsevier Inc. All rights reserved.
6.	Eriksson, Jonny, et al. (författare) Model cellulose films exposed to H-insolens glucoside hydrolase family 45 endo-cellulase - the effect of the carbohydrate-binding module 2005 Ingår i: Journal of Colloid and Interface Science. - : Elsevier BV. - 1095-7103 .- 0021-9797. ; 285:1, s. 94-99 Tidskriftsartikel (refereegranskat)abstract The effects of enzyme structure and activity on the degradation of model cellulose substrates were investigated by ellipsometry for the cellulase Humicola insolens GH45. The inactive variant D10N was found to adsorb at the cellulose surface but also to be incorporated into the cellulose films to an extent that depended on pH. For the native protein, the initial adsorption monitored for the inactive variant D10N was followed by enzyme-mediated degradation of the cellulose films. Again, a dependence on pH was found, such that higher pH resulted in slower enzymatic degradation. Removing the carbohydrate-binding module eliminated this pH dependence but also resulted in a decreased adsorption to the cellulose surface, and in a decreased net catalytic effect. (c) 2004 Elsevier Inc. All rights reserved.
7.	Gopinath, Varun, 1982-, et al. (författare) Safe Assembly Cell Layout through Risk Assessment : An Application with Hand Guided Industrial Robot 2017 Ingår i: Proceedings of the 50th CIRP Conference on Manufacturing Systems. - : Elsevier. ; , s. 430-435, s. 430-435 Konferensbidrag (refereegranskat)abstract Risk assessment is a systematic and iterative process which involves risk analysis where the probable hazards are identified and corresponding risks are evaluated along with solutions to mitigate the effect of these risks. In this article the outcome of a risk assessment process will be detailed where a large industrial robot is being used as a intelligent and flexible lifting tool that can aid operators in assembly tasks. The realization of a collaborative assembly station has several benefits such as increased productivity and improved ergonomic work environment. The article will detail the design of the layout of a collaborative assembly cell which takes into account the safety and productivity concerns of automotive assembly plants.
8.	Gopinath, Varun, 1982-, et al. (författare) Safety-Focussed Design of Collaborative Assembly Station with Large Industrial Robots 2018 Ingår i: Procedia Manufacturing. - : Elsevier. - 2351-9789. ; 25, s. 503-510 Tidskriftsartikel (refereegranskat)abstract The perceived benefits of large industrial robots for collaborative operations are characteristics such as long reach with heavy load carrying capability. Collaborative operations refers to situations where operators and robots share a workspace to complete tasks in close proximity. This mode of operation coupled with the physical characteristics of large robots represents high risks to injury and for these reasons, the safeguarding of the workspaces needs to be achieved in conjunction with the tasks to be performed within the workstation. This article will detail two workstations that was developed in a laboratory environment and are partial results of a research project titled ToMM2, whose aim was to understand safety issues associated with collaborative operations with large robots.
9.	Haghighi, Mona, et al. (författare) A Comparison of Rule-based Analysis with Regression Methods in Understanding the Risk Factors for Study Withdrawal in a Pediatric Study 2016 Ingår i: Scientific Reports. - : Springer Science and Business Media LLC. - 2045-2322. ; 6 Tidskriftsartikel (refereegranskat)abstract Regression models are extensively used in many epidemiological studies to understand the linkage between specific outcomes of interest and their risk factors. However, regression models in general examine the average effects of the risk factors and ignore subgroups with different risk profiles. As a result, interventions are often geared towards the average member of the population, without consideration of the special health needs of different subgroups within the population. This paper demonstrates the value of using rule-based analysis methods that can identify subgroups with heterogeneous risk profiles in a population without imposing assumptions on the subgroups or method. The rules define the risk pattern of subsets of individuals by not only considering the interactions between the risk factors but also their ranges. We compared the rule-based analysis results with the results from a logistic regression model in The Environmental Determinants of Diabetes in the Young (TEDDY) study. Both methods detected a similar suite of risk factors, but the rule-based analysis was superior at detecting multiple interactions between the risk factors that characterize the subgroups. A further investigation of the particular characteristics of each subgroup may detect the special health needs of the subgroup and lead to tailored interventions.
10.	Henriksson, Fredrik, 1988-, et al. (författare) An outlook on multi material body solutions in the automotive industry – possibilities and manufacturing challenges 2016 Ingår i: SAE Technical Paper Series. - Detroit (MI), USA : Society of Automotive Engineers. - 0148-7191. Konferensbidrag (refereegranskat)abstract In the automotive industry, mass reduction and lightweight design is a continuing trend that does not show signs of declining. When looking at where to reduce weight in a vehicle, the body is a preferential subsystem due to its large contribution to overall mass and the stability of body composition over a specific model range. The automotive industry of today moves toward a greater differentiation in materials that compose a car, which can be seen in the several different multi material vehicle bodies that have been introduced by manufacturers in recent years. But while mixing materials may contribute to a good compromise between weight reduction and vehicle cost, it also proposes a number of challenges that need to be addressed. Among other material factors, the different coefficients of thermal expansions might introduce new stresses during painting and curing. Joining processes and possible chemical reactions between materials also needs to be taken into account, the same with the question of whether to integrate or differentiate different functions in a system. If the manufacturing plant uses mixed model assembly lines, design of end effectors for gripping multiple different materials is another challenge not previously encountered in this context. In this paper, a number of production and manufacturing related challenges are discussed, and the authors highlight different areas where the requirements of design engineering tools needs to be evaluated for these new multi material concepts and design decisions in order for automotive manufacturers to ensure future market competitiveness.
11.	Henriksson, Fredrik, et al. (författare) Challenges when working with renewable materials: knocking on wood? 2021 Ingår i: International Journal of Sustainable Engineering. - : Taylor & Francis. - 1939-7038 .- 1939-7046. ; 14:6, s. 1980-1987 Tidskriftsartikel (refereegranskat)abstract With sustainable design as a vital strategical component for companies competing on the market today, many companies will need to transition to a use of sustainable and/or renewable materials in the near future. But how can this be done, and what can be done to bridge the gap from current affairs to a new, more sustainable state? Looking towards industries with experience might help making the first step just a little bit easier. This study aims to find challenges and bottlenecks when working with sustainable materials, in order to help companies interested in transitioning towards using sustainable or renewable materials in their products. The paper describes an interview study with five Swedish wood industry companies, differentiated in size and products, where the authors identify several key findings for both industry (already working with wood or aiming at transitioning towards renewable materials) and academia (on using renewable materials, need for further research, and pointers for teaching design and engineering students). Findings range from how organisational culture affects material selection, to how flexibility and efficiency effects automation solutions via how these companies have approached outsourcing of parts of their production.
12.	Henriksson, Fredrik, 1988-, et al. (författare) Including Student Case Projects in Integrated Product and Production Development Research – Methodology Description and Discussion 2016 Konferensbidrag (övrigt vetenskapligt/konstnärligt)abstract Within integrated product and production development research, casestudies needto be performed for data gathering purposes. Today, there are two commonly used ways to perform this research; observingindustry projects orhaving the researchers perform the projects themselves. The first option can pose data access and IPRissues, and the second optioncomes with biasing risks. Another approach is to work with studentcaseprojects, givingstudents interesting projects and findinga solution to mediate both data gathering opportunity and biasing risks. This approach has been tested at Linköping University, with students performing projects in the Vinnovafunded Production 2030 –Large Scale Production in Mixed Materials project. Two larger student case projects have been performed on the topic of material substitution and mixed material solutions within the automotive industry.In this paper, the method used to include student projects is presented along with identified benefits and drawbacks. Including student case projects in research have shown to be beneficial in research on processes, projects and methodology, but needs to be complemented by data fromindustry projects and the researcher ́s own work within integrated product and production development in order to create a more reliable analysis with high level of detail.
13.	Henriksson, Fredrik, 1988-, et al. (författare) Integrated Product and Production Research on Introducing Internet of Things in Swedish Wood Industry Products 2018 Ingår i: Procedia Manufacturing. - : Elsevier. - 2351-9789. ; 25, s. 10-16 Tidskriftsartikel (refereegranskat)abstract To enable transitioning the Swedish economy into a bioeconomy, Swedish wood industry need to increase added value and introduce new products to market by introducing new technology and improving the product and production development processes. Research in automotive industry have shown the need for integrating product and production development when introducing new technology in existing production systems, and have indicated a possibility of using specifically designed student case projects in order to generate qualitative data. In this paper, one student case project on product and production development in the Swedish wood industry, involving IoT wood products, is presented and evaluated.
14.	Henriksson, Fredrik, 1988- (författare) Introducing New Materials in the Automotive Industry : Managing the Complexity of Introducing New Materials in Existing Production Systems 2017 Licentiatavhandling (övrigt vetenskapligt/konstnärligt)abstract Passenger vehicles are central to Western society, and contribute to a signiﬁcant part of our greenhouse gas emissions. In order to reduce emissions, the automotive industry as a whole is working to reduce mass in passenger vehicles in order to reduce energy consumption. One way to reduce mass is to introduce lightweight materials in the body of the vehicle. This research aims to explore the relationship between product and production system when introducing new materials.Besides a theoretical review and an industry-centered technological mapping, four case studies have been conducted during the course of this licentiate thesis. Two case studies were conducted with engineering design students working as development teams, one case study with the author as the developer and ﬁnally one case study in an industrial environment at a product owning company with in-house production. The goal of the case studies has been to increase the collective knowledge of how product development decisions affect production development decisions, and vice versa, when developing passenger vehicles in new materials.In the following analysis of case study outcomes, a number of factors important for introducing new materials are discussed. The relationship between product and production is investigated, both in terms of how the production system affects the product and how the product affects the production system. The outcome from this analysis is a mapping of important factors for automotive industry companies to understand and identify when looking at introducing new materials in existing production systems. Finally, a suggestion for future research efforts is presented.
15.	Henriksson, Fredrik, 1988- (författare) On Material selection and its consequences in product development 2021 Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract Technological development, and increased demands on sustainable solutions, have impacted the development of new products. New products need to be more efficient, and there are increased possibilities for a more diversified and informed decision regarding what materials are used in the product. However, how can engineers and designers be helped in their efforts to make better decisions regarding materials?In this research, carried out via multiple case studies and action research, behaviors regarding material selection and material management are examined. The data has been collected using participation action research, observations, and interviews as the primary sources of information. The author has conducted participation action research integrated into an industrial environment, multiple case studies using students in industrial design engineering have been done, and the researcher has performed interview studies with industry representatives. The behaviors described in the empirical studies are contrasted with basic decision theory and analysis of established product development methodology, asking the questions: Are basic assumptions built into models and methods taught to designers and engineers valid?The research presented in this thesis shows that there are personal, technical, and organizational aspects to selecting and managing materials in product development. This work has also shown that assuming rationality, something that is built into methods and models as well as taught to engineering students, is not valid in decision-making; human beings are not rational, and entirely rational decisions are not possible due to the vast data and prediction needs to be able to make entirely rational decisions. Even when assuming some variant of bounded rationality, multiple factors described in decision theory are not acknowledged in product development methodology. Two of these can be described as identity (both personal and professional) and mental models of materials.The discrepancy in how decisions are described in decision theory and how methods for decision-making are designed in product development risks inhibit the introduction of new and more sustainable materials in products. This could be because non-rational aspects of decision-making are incorporated in the decision-making under the assumption of rationality. It could also be because of the mental models of materials affecting what the designers and engineers think they can do with a particular material. These behaviors make the risks of introducing new materials too big for a designer or engineer to accept.Outcomes from this research show that additional data will not be enough to persuade designers and engineers to select new material to its fullest extent. This can slow down sustainability improvements in products. To counter this, it is suggested that the personal and non-rational side of decision-making is acknowledged and valued, that visions and ideology are used to encourage the introduction of new materials rather than relying on technical or economic aspects, and that designers and engineers are encouraged and enabled to take higher risks and evaluate more “unknown” parameters.To fully implement these suggestions, the following three things need to happen:A: Design and engineering education needs to teach students how to have more flexible mental models of materialsB: Industry should find ways for designers and engineers to experiment further and learn (both on an organizational and personal level)C: Academia should further investigate how behaviors, mental models and habits affect product development and design work, especially regarding material selection and material management.
16.	Henriksson, Fredrik, 1988-, et al. (författare) On Material Substitution in Automotive BIWs – From Steel to Aluminum Body Sides 2016 Ingår i: 26th CIRP Design Conference. - : Elsevier. ; , s. 683-688 Konferensbidrag (refereegranskat)abstract Weight reduction and material substitution are increasing trends in the automotive industry. In this project, the task of substituting the steel body side in the monocoque of a large SUV towards an aluminum body side was investigated through a design engineering approach adopting a breadth-first analysis method. One conclusion based on the analysis is that the choice of joining technology would become arbitrary due to the breadth-first approach. In this paper, the authors present their findings from the aforementioned case, including the challenges with switching between materials with fundamentally different properties when performing material substitution projects. The possibility of having taken a depth-first analysis approach, and the possible effects on the project result, is discussed.
17.	Henriksson, Fredrik, 1988-, et al. (författare) Product development in the Swedish Automotive industry: Can design tools be viewed as decision support systems? 2015 Konferensbidrag (övrigt vetenskapligt/konstnärligt)abstract Design engineers working in the automotive industry have to take many design decisions, based on numerous diverse criteria. This results in a high workload of complex decisions. One way to reduce decision complexity and improve decisions could be to improve design tools. Decision support systems (DSSs) have been used in a managerial context to improve decisions. In this article, the authors assess whether design tools generally can be viewed as DSSs. A combination of literature review, surveys and qualitative interviews with seven design engineers was used to assess whether current design tools function as decision supports in product development. Although the specific design context needs to be considered, this study’s results suggest that design tools can generally function as DSSs. In future work, the adaptability to different problem solving patterns needs further in-depth research in the form of individual studies for specific tools in specific contexts.
18.	Henriksson, Fredrik, 1988-, et al. (författare) Student-developed laboratory exercises - An approach to cross-disciplinary peer education 2016 Ingår i: Proceedings of NordDesign 2016. - : The Design Society. - 9781904670803 - 9781904670810 ; , s. 226-235 Konferensbidrag (refereegranskat)abstract With new technologies and demands from industry, universities need to adapt in order to educate engineers suited for the job market of tomorrow. Focusing on the fields of product development and mechanical engineering, topics such as new lightweight materials and lightweight designs are currently a focus of many industries, and the demand from industry is that engineers graduating should have some knowledge in these fields. In this case, a project was set up for a student-developed laboratory exercise in lightweight material, focusing on the interconnection between material properties, geometry and manufacturing technology in order to fulfil a contextual requirement. The industry chosen was the aircraft industry, due to its heavy emphasis on light weight. The chosen component (a civil aircraft radome) meant that material properties not necessarily connected to high specific strength became important, something that adds educational value to the exercise. Since the introduction of the exercise, the plan is to introduce the laboratory exercise in more courses where the interdisciplinary connections between material properties, geometry and manufacturing technology needs to be explained for students as well as evaluate how this approach to exercise development can be improved and further utilized. This paper presents the learnings from setting up the laboratory exercise, as well as discusses the possibilities of thesis works as an enabler for peer education and puts these in a context for a future, adaptive engineering education that quickly can add or renew material in the curriculum without substantial investment of resources.
19.	Henriksson, Fredrik, 1988-, et al. (författare) Towards Applying The Boothroyd, Dewhurst and Knight Methodology for Cost Estimation on Fibre Composite Manufacturing - A Theoretical Approach 2014 Ingår i: Proceedings of The 6th International Swedish Production Symposium 2014. - Gothenburg. - 9789198097412 Konferensbidrag (refereegranskat)abstract Increased usage of carbon fibre composite poses challenges for the automotive industry; one is to manage carbon fibre composites within the product development process. This paper combines knowledge in design engineering, material science and production technology, aiming to bridge these domains. The study indicates that mass production methods suitable for carbon fibre have several factors in common with traditional polymer production methods. Thus, it is possible that DfMA methods for traditional polymer production can be adjusted for carbon fibre composite production. The result is summarised in a table aiming to facilitate engineering decisions related to cost estimations for composite moulding.
20.	Henriksson, Fredrik, 1988-, et al. (författare) University as a Laboratory : Exploring how engineering education can support industrial needs 2018 Ingår i: NordDesign 2018. - 9789176851852 Konferensbidrag (refereegranskat)abstract Universities have two major tasks; generating knowledge through research and educating students for academia, the public sector and the industry. In this paper, the authors explore how engineering education can support industrial needs on two fronts: creating a case study platform for research and preparing graduating engineering students to become more capable engineers when beginning their working life in industry, by applying the ""University as a laboratory"" concept. ""University as a laboratory"", as coined by Henriksson (2017), means that research-based case study projects are brought into educational courses where students are assigned to work as engineering designers, and researchers can observe problem solving patterns and evaluate different methodologies (also presented by Henriksson and Johansen (2016)). Though the concept have been presented earlier (Henriksson and Johansen 2016, Henriksson 2017), a more thorough evaluation is in order to further understand the effects of integrating research and education in the ""University as a laboratory"" concept. This is done through the performance and evaluation of a research-based engineering design education project in collaboration with automotive industrial partners; a project on lightweight and sustainable product and production development. The study evaluates three aspects of the project; the researchers' view, the teachers' view and the students' view. Data on all three aspects has been gathered through group interviews, observations and written assignments during the project, as well as interviews with participating students one year after the end of the project and workshops with researchers and teachers involved in the project. Analysis has been done on a qualitative basis, to investigate whether case projects are suitable for deep understanding in engineering fields and whether project courses are suitable to test different approaches of integrated product and production development.
21.	Johansen, Daniel, et al. (författare) A comparative study of virtual hand prosthesis control using an inductive tongue control system 2016 Ingår i: Assistive Technology. - : Informa UK Limited. - 1040-0435 .- 1949-3614. ; 28:1, s. 22-29 Tidskriftsartikel (refereegranskat)abstract This study compares the time required to activate a grasp or function of a hand prosthesis when using an electromyogram (EMG) based control scheme and when using a control scheme combining EMG and control signals from an inductive tongue control system (ITCS). Using a cross-over study design, 10 able-bodied subjects used a computer model of a hand and completed simulated grasping exercises. The time required to activate grasps was recorded and analyzed for both control schemes. End session mean activation times (ATs; seconds) for the EMG control scheme grasps 1 -5 were 0.80, 1.51, 1.95, 2.93, and 3.42; for the ITCS control scheme grasps 1 5 they were 1.19, 1.89, 1.75, 2.26, and 1.80. Mean AT for grasps 1 and 2 was statistically significant in favor of the EMG control scheme (p = 0.030; p = 0.004). For grasp 3 no statistical significance occurred, and for grasps 4 and 5 there was a statistical significance in favour of the ITCS control scheme (p = 0.048; p = 0.004). Based on the amount of training and the achieved level of performance, it is concluded that the proposed ITCS control scheme can be used as a means of enhancing prosthesis control.
22.	Johansen, J. G., et al. (författare) Experimental study of bound states in Be-12 through low-energy Be-11(d,p)-transfer reactions 2013 Ingår i: Physical Review C - Nuclear Physics. - 2469-9985 .- 2469-9993. ; 88:4 Tidskriftsartikel (refereegranskat)abstract The bound states of Be-12 have been studied through a Be-11(d, p) Be-12 transfer reaction experiment in inverse kinematics. A 2.8 MeV/u beam of Be-11 was produced using the REX-ISOLDE facility at CERN. The outgoing protons were detected with the T-REX silicon detector array. The MINIBALL germanium array was used to detect gamma rays from the excited states in Be-12. The gamma-ray detection enabled a clear identification of the four known bound states in Be-12, and each of the states has been studied individually. Differential cross sections over a large angular range have been extracted. Spectroscopic factors for each of the states have been determined from distorted wave Born approximation (DWBA) calculations and have been compared to previous experimental and theoretical results.
23.	Johansen, Sys Stybe, et al. (författare) Temporal patterns of tramadol in hair after a single dose 2020 Ingår i: Forensic Science International. - : ELSEVIER IRELAND LTD. - 0379-0738 .- 1872-6283. ; 316 Tidskriftsartikel (refereegranskat)abstract This controlled study aimed to measure concentrations of tramadol (TRA) and its two main metabolites, N-desmethyltramadol (NDMT) and O-desmethyltramadol (ODMT), in hair following a single dose ingestion and to investigate the distribution patterns in hair by segmental analysis of hair samples taken at several sampling time points after ingestion. An oral dose (50 or 100 mg) of TRA was administered to 17 healthy volunteers. Hair samples were collected prior to drug administration and 14, 30, 60 and 120 days after ingestion. Each sample was segmented in 5 mm segments and washed. The analytes were extracted from pulverized hair by incubation in extraction media for 18 h at 37 degrees C. A validated UHPLC-MS/MS method was used to quantify the analytes at a LLOQ of 0.001 ng/mg. Hair segments corresponding to the time of ingestion were positive for TRA and the metabolites of each sampling time point, although neighboring segments also showed positive results. The highest concentrations for both dosage groups were observed in the proximal segment of hair collected 14 days after ingestion for all subjects: 0.061-0.95 ng TRA/mg, 0.012-0.86 ng NDMT/mg and 0.009-0.17 ng ODMT/mg (n = 16). Generally, the TRA concentration was higher than the metabolites concentrations but depended on the CYP2D6 phenotype. The metabolite to TRA ratios were stable within a subject over the sampling time points, however it varied greatly between subjects. No significant differences in hair concentrations were found between the two dosage groups at each sampling time. Several confounding factors were identified such as hair pigmentation and internal sweat. We showed that analysis of 5 mm segments improved the determination of the exposure time after a single ingestion of TRA. In addition, in the later sampling time points the analytes were spread more between segments and the total drug amount of each later sampling time point declined up to a 100% (median: 75%) due to wash out. The presented results are important additions to the sparse literature reporting single dose of psychoactive drugs in hair. (C) 2020 Elsevier B.V. All rights reserved.
24.	Johnson, Randi K., et al. (författare) Metabolite-related dietary patterns and the development of islet autoimmunity 2019 Ingår i: Scientific Reports. - : Springer Science and Business Media LLC. - 2045-2322. ; 9:1 Tidskriftsartikel (refereegranskat)abstract The role of diet in type 1 diabetes development is poorly understood. Metabolites, which reflect dietary response, may help elucidate this role. We explored metabolomics and lipidomics differences between 352 cases of islet autoimmunity (IA) and controls in the TEDDY (The Environmental Determinants of Diabetes in the Young) study. We created dietary patterns reflecting pre-IA metabolite differences between groups and examined their association with IA. Secondary outcomes included IA cases positive for multiple autoantibodies (mAb+). The association of 853 plasma metabolites with outcomes was tested at seroconversion to IA, just prior to seroconversion, and during infancy. Key compounds in enriched metabolite sets were used to create dietary patterns reflecting metabolite composition, which were then tested for association with outcomes in the nested case-control subset and the full TEDDY cohort. Unsaturated phosphatidylcholines, sphingomyelins, phosphatidylethanolamines, glucosylceramides, and phospholipid ethers in infancy were inversely associated with mAb+ risk, while dicarboxylic acids were associated with an increased risk. An infancy dietary pattern representing higher levels of unsaturated phosphatidylcholines and phospholipid ethers, and lower sphingomyelins was protective for mAb+ in the nested case-control study only. Characterization of this high-risk infant metabolomics profile may help shape the future of early diagnosis or prevention efforts. © 2019, The Author(s).
25.	Krischer, Jeffrey P, et al. (författare) Predicting Islet Cell Autoimmunity and Type 1 Diabetes : An 8-Year TEDDY Study Progress Report 2019 Ingår i: Diabetes Care. - : American Diabetes Association. - 1935-5548 .- 0149-5992. ; 42:6, s. 1051-1060 Tidskriftsartikel (refereegranskat)abstract OBJECTIVE: Assessment of the predictive power of The Environmental Determinants of Diabetes in the Young (TEDDY)-identified risk factors for islet autoimmunity (IA), the type of autoantibody appearing first, and type 1 diabetes (T1D).RESEARCH DESIGN AND METHODS: A total of 7,777 children were followed from birth to a median of 9.1 years of age for the development of islet autoantibodies and progression to T1D. Time-dependent sensitivity, specificity, and receiver operating characteristic (ROC) curves were calculated to provide estimates of their individual and collective ability to predict IA and T1D.RESULTS: HLA genotype (DR3/4 vs. others) was the best predictor for IA (Youden's index J = 0.117) and single nucleotide polymorphism rs2476601, in PTPN22, was the best predictor for insulin autoantibodies (IAA) appearing first (IAA-first) (J = 0.123). For GAD autoantibodies (GADA)-first, weight at 1 year was the best predictor (J = 0.114). In a multivariate model, the area under the ROC curve (AUC) was 0.678 (95% CI 0.655, 0.701), 0.707 (95% CI 0.676, 0.739), and 0.686 (95% CI 0.651, 0.722) for IA, IAA-first, and GADA-first, respectively, at 6 years. The AUC of the prediction model for T1D at 3 years after the appearance of multiple autoantibodies reached 0.706 (95% CI 0.649, 0.762).CONCLUSIONS: Prediction modeling statistics are valuable tools, when applied in a time-until-event setting, to evaluate the ability of risk factors to discriminate between those who will and those who will not get disease. Although significantly associated with IA and T1D, the TEDDY risk factors individually contribute little to prediction. However, in combination, these factors increased IA and T1D prediction substantially.

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