Osteoarthritis (OA) is characterized by pain, and problems with activities of daily life, especially if the hip or knee joint is affected. The aim of this project was to study associations between strength, voluntary activation and physical functioning in elderly patients with OA. People with OA of the knee often have lower muscle strength, but also a lower ability to voluntarily activate their knee extensors. In Chapter 2 we investigated the effects of relatively low stimulation currents on the assessment of VA of the knee extensor muscles. We concluded that by using submaximal muscle stimulation overestimation of VA may even be less compared with maximal nerve stimulation. In Chapter 3, we investigated physical functioning longitudinally in a large cohort of participants with and without self-reported hip or knee OA. Physical functioning was tested with a short battery consisting of a chair stand test, a balance test and a 6 meter walk test, performed in the participants’ home. Chair stand and walking performance were lower in participants with OA 3 to 6 years after OA was reported for the first time, and men were more affected than women. In the laboratory, more elaborate lab tests can be done, such as muscle function tests, standardized stair climb tests and longer walk tests. Such tests may be more sensitive to detect impairments. In Chapter 4, we investigated whether there are differences in muscle function in people with and without OA, Only the battery of home tests showed lower scores in participants with OA, and there were no differences in muscle function. In Chapter 5, we investigated the feasibility and effectiveness of 6 weeks of preoperative training for elderly OA patients undergoing total knee arthroplasty. Pre and post-operative outcome measures were not different compared to a standard training group. We conclude that physical functioning, but not VA is impaired in older people with OA and that strength and physical functioning is more impaired just before total knee arthroplasty. When assessing physical functioning in older participants or patients with musculoskeletal disorders, home tests are a good alternative to lab tests to obtain a representative sample. Preoperative training before total knee arthroplasty can prevent the decline in functioning often observed before surgery, but there were no additional effects of intensive strength training.
Background: Research has shown that the course of non-specific low back pain (LBP) is influenced by, among other factors, patients' self-management abilities. Therefore, clinical guidelines recommend stimulation of self-management. Enhancing patients' self-management potentially can improve patients' health outcomes and reduce future healthcare costs for non-specific LBP. Objectives: Which characteristics and health outcomes are associated with activation for self-management in patients with non-specific LBP? Design: Cross-sectional study. Method: Patients with non-specific LBP applying for primary care physiotherapy were asked to participate. Multivariable linear regression analysis was performed to analyze the multivariable relationship between activation for self-management (Patient Activation Measure, range 0-100) and a range of characteristics, e.g., age, gender, and health outcomes, e.g., self-efficacy, pain catastrophizing. Results: The median activation for self-management score of the patients with non-specific LBP (N = 208) was 63.10 (IQR = 19.30) points. The multivariable linear regression analysis revealed that higher self-efficacy scores (B = 0.54), female gender (B = 3.64), and a middle educational level compared with a high educational level (B = -5.47) were associated with better activation for self-management in patients with non-specific LBP. The goodness-of-fit of the model was 17.24% (R2 = 0.17). Conclusions: Patients with better activation for self-management had better self-efficacy, had a higher educational level, and were more often female. However, given the explained variance better understanding of the factors that influence the complex construct of self-management behaviour in patients who are not doing well might be needed to identify possible barriers to engage in self-management.
Self-efficacy and outcome expectations regarding client activation determine professionals’ level of actively engaging clients during daily activities. The Client Activation Self-Efficacy and Outcome Expectation Scales for nurses and domestic support workers (DSWs) were developed to measure these concepts. This study aimed to assess their psychometric properties. Cross-sectional data from a sample of Dutch nurses (n=150) and DSWs (n=155) were analysed. Descriptive statistics were used to examine floor and ceiling effects. Construct validity was assessed by testing research-based hypotheses. Internal consistency was determined with Cronbach’s alpha. The scales for nurses showed a ceiling effect. There were no floor or ceiling effects in the scales for domestic support workers. Three out of five hypotheses could be confirmed (construct validity). For all scales, Cronbach’s alpha coefficients exceeded 0.70. In conclusion, all scales had moderate construct validity and high internal consistency. Further research is needed concerning their construct validity, testretest reliability and sensitivity to change.
Paper sludge contains papermaking mineral additives and fibers, which could be reused or recycled, thus enhancing the circularity. One of the promising technologies is the fast pyrolysis of paper sludge, which is capable of recovering > 99 wt.% of the fine minerals in the paper sludge and also affording a bio-liquid. The fine minerals (e.g., ‘circular’ CaCO3) can be reused as filler in consumer products thereby reducing the required primary resources. However, the bio-liquid has a lower quality compared to fossil fuels, and only a limited application, e.g., for heat generation, has been applied. This could be significantly improved by catalytic upgrading of the fast pyrolysis vapor, known as an ex-situ catalytic pyrolysis approach. We have recently found that a high-quality bio-oil (mainly ‘bio-based’ paraffins and low-molecular-weight aromatics, carbon yield of 21%, and HHV of 41.1 MJ kg-1) was produced (Chem. Eng. J., 420 (2021), 129714). Nevertheless, catalyst deactivation occurred after a few hours’ of reaction. As such, catalyst stability and regenerability are of research interest and also of high relevance for industrial implementation. This project aims to study the potential of the add-on catalytic upgrading step to the industrial fast pyrolysis of paper sludge process. One important performance metric for sustainable catalysis in the industry is the level of catalyst consumption (kgcat tprod-1) for catalytic pyrolysis of paper sludge. Another important research topic is to establish the correlation between yield and selectivity of the bio-chemicals and the catalyst characteristics. For this, different types of catalysts (e.g., FCC-type E-Cat) will be tested and several reaction-regeneration cycles will be performed. These studies will determine under which conditions catalytic fast pyrolysis of paper sludge is technically and economically viable.
Mycelium biocomposites (MBCs) are a fairly new group of materials. MBCs are non-toxic and carbon-neutral cutting-edge circular materials obtained from agricultural residues and fungal mycelium, the vegetative part of fungi. Growing within days without complex processes, they offer versatile and effective solutions for diverse applications thanks to their customizable textures and characteristics achieved through controlled environmental conditions. This project involves a collaboration between MNEXT and First Circular Insulation (FC-I) to tackle challenges in MBC manufacturing, particularly the extended time and energy-intensive nature of the fungal incubation and drying phases. FC-I proposes an innovative deactivation method involving electrical discharges to expedite these processes, currently awaiting patent approval. However, a critical gap in scientific validation prompts the partnership with MNEXT, leveraging their expertise in mycelium research and MBCs. The research project centers on evaluating the efficacy of the innovative mycelium growth deactivation strategy proposed by FC-I. This one-year endeavor permits a thorough investigation, implementation, and validation of potential solutions, specifically targeting issues related to fungal regrowth and the preservation of sustained material properties. The collaboration synergizes academic and industrial expertise, with the dual purpose of achieving immediate project objectives and establishing a foundation for future advancements in mycelium materials.
What if living organisms communicated signals from the environment to us and thereby offered a sustainable alternative to electronic sensors? Within the field of biodesign, designers and scientists are collaborating with living organisms to produce new materials with ecological benefits. The company Hoekmine, in collaboration with designers, has been researching the potential of flavobacteria for producing sustainable colorants to be applied on everyday products. These non-harmful bacteria can change their form, texture and iridescent color in response to diverse environmental factors, such as humidity and temperature. Here, billions of cells are sensing and integrating the results as color. Therefore, Hoekmine envisions biosensors, which would minimize the use of increasingly demanded electronic sensors, and thus, the implementation of scarce and toxic materials. Developing a living sensor by hosting flavobacteria in a biobased and biodegradable flexible material offers opportunities for sustainable alternatives to electronic sensors. Aiming to take this concept to the next level, we propose a research collaboration between Avans, Hoekmine and a company specialized in biobased and biodegradable labels, Bio4Life. Together with this interdisciplinary team, we aim to bridge microbiology and embodiment design, and contribute to the development of a circular economy where digital technology and organic systems merge in the design of Living Circular Labels (LCLs). Throughout the project we will use an iterative approach between designing and testing LCLs that host living flavobacteria and additionally, methods for the end user to activate the bacteria’s growth at a given time.
