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Vaikuttaako asuinpaikka maahanmuuttoasenteeseen? : Kvantitatiivinen analyysi suomalaisten maahanmuuttoasenteista
No full textThe power of prevention and valorisation – Environmental impacts of reducing surplus and waste of bakery products at retail
No full textThe wastage of edible food still remains a major global challenge, despite its well-known consequences. Although bread and bakery products are identified as some of the most frequently wasted foods, the amounts generated and the pathways used to manage this surplus are often unknown. To support sustainable food systems, there is an urgent need to identify how much surplus is generated along the supply chain, including both sweet and savoury products, and to map how this resource is managed. The aim of this study was to quantify the surplus and waste of baked goods in Sweden, alongside mapping the pathways used for managing unsold bread generated at the supplier-retailer interface. Life cycle assessment, considering 18 midpoint indicators and one endpoint indicator, was used to assess the environmental benefits of reducing bakery product surplus. The results reveal that nearly 180,000 t of baked goods are wasted annually in Sweden. Roughly 51 % is generated at the supplier-retailer interface, particularly considering bread sold under take-back agreements where 14 % of production becomes surplus. Only 2 % of this surplus is recirculated to the food system, while the majority is instead used in energy production. Scenario analyses, including nine scenarios designed to capture various innovations to reduce surplus, demonstrated that prevention and valorisation strategies, such as data sharing and price reductions, have the greatest potential for reducing waste and environmental impact. Prevention could result in up to ten times lower climate impact per kg bread. The findings offer valuable insights for future research on sustainable food systems, and can act as practical guidance for industry actors, stakeholders, and policymakers to implement waste-reduction strategies that promote sustainable, resource-efficient food systems.Peer reviewe
Governing uncertainty by anticipating risk: assessing crisis management during COVID-19
No full textThis chapter takes stock of anticipatory practices in the context of governmental responses to unanticipated crisis situations, using the COVID-19 pandemic as a case study. It pays particular attention to the role of public decision-making within the context of anticipatory governance. Practices are connected to policy instruments and ultimately to an understanding of the role of the state as well as to fundamental assumptions about how state agencies (at multiple levels) ought to respond to emerging crises. Empirically, we base our analysis on 42 semi-structured interviews with key actors in the Finnish central administration working with government responses to COVID-19. The results show the centrality of bounded rationality in handling risks in data management, problem-solving, and decision-making. The findings offer key insights into the causes, processes, and consequences of crisis management within government in the context of complex and evolving governance systems during periods of turbulence.Peer reviewe
Environmental performance of biomethanation based on life cycle assessment
No full textClimate change has recently had a significant impact on the environment, necessitating a shift from fossil-based to renewable energy sources. A promising long-term storage solution for renewable energy is the production of hydrogen through electrolysis, known as green hydrogen. This hydrogen can be utilized in Power-to-X applications, such as power-to-gas, where captured CO2 is used for methanation with hydrogen. Employing biomethane in place of natural gas in the transportation sector can significantly reduce greenhouse gas emissions. There is a research gap in the absence of comprehensive LCA studies comparing in-situ and ex-situ biomethanation processes with traditional biogas upgrading methods. The aim of the study is to evaluates the environmental performance of using hydrogen in in-situ and ex-situ biomethanation to increase methane content in biogas for heavy-duty vehicles, comparing these methods with traditional membrane separation upgrading. Through LCA, the climate change impact shows a 52 % reduction in emissions for membrane separation compared to fossil-based scenarios. Ex-situ biomethanation results in a 44%–54 % reduction, while in-situ biomethanation achieves 43%–53 %, depending on the electricity source for hydrogen production. Acidification and marine eutrophication impacts are higher in alternatives using grid electricity, while freshwater eutrophication stems from solar-powered hydrogen electrolysis. These findings underscore the importance of integrating renewable energy sources and advanced biogas upgrading techniques to achieve significant environmental benefits. The novelty of this research lies in its comprehensive LCA comparing traditional and innovative biogas upgrading technologies, providing valuable insights for future energy and environmental strategies.Peer reviewe
Incidence of constrained condylar and hinged knee implants and mid-to long-term survivorship: a register-based study from the Nordic Arthroplasty Register Association (NARA)
No full textBackground and purpose — In complex primary total knee arthroplasty (TKA), constrained condylar knee (CCK) or rotating hinge knee (RHK) designs may be required to provide stability or address bony deficiencies. We analyzed trends in incidence of these designs in primary TKA and evaluated the mid-to long-term survivorship of CCK and RHK in 4 Nordic countries. Methods — From 2000 to 2017, 5,134 CCK and 2,515 RHK primary TKAs were identified from the NARA data-base. Kaplan–Meier (K–M) survival and flexible parametric survival model (FPSM) analyses were performed to estimate revision risk, expressed as hazard ratio (HR) with 95% con-fidence intervals (CI), with minimally stabilized (MS) TKA acting as the control group (n = 456,137). Results — The incidence of CCK and RHK implants increased significantly in Finland, while it was moderate in Denmark, Norway, and Sweden. With revision for any reason as the endpoint the 15-year K–M cumulative revision risk for RHK was 13.6% (CI 10.4–16.7) and for CCK it was 11.3% (CI 9.1–13.5). Compared with MS TKA, the hazard ratio for revision was 2.1 (CI 1.8–2.3) for CCK and 2.5 (CI 2.1–2.8) for RHK. Periprosthetic joint infection (PJI) was the most common reason for revision, accounting for 44% of CCK and 47% of RHK cases. After excluding revisions for PJI, the hazard ratio remained high for both designs, at 1.5 (CI 1.3–1.7) for CCK and 1.6 (CI 1.3–2.0) for RHK compared with MS. Conclusion — The incidence of CCK and RHK increased during the study period. Both designs showed consistent 15-year revision risks of 11–14%, with no major differences between them. The higher revision risk compared with MS TKAs may reflect the complexity of the surgeries.Peer reviewe
Dynamic modeling of a heavy-duty skid-steer mobile robot
Get PDFThe trend towards autonomy in heavy-duty mobile work machines used in e.g. construction, forestry, and mining has been significant in recent years. Precise driving is an important aspect of the autonomous operation of these machines. To ensure accurate path-following control, a model-based control architecture is often the choice. For passenger vehicles, kinematic models are usually valid up to a certain velocity. However, the forces and torques in heavy-duty off-road vehicles are significantly higher already at low speeds, leaving no option but to use dynamic models to obtain sufficient accuracy.
This thesis aimed to develop a dynamic model concerning the driving aspects of a heavy-duty skid-steer mobile robot. The goal was to develop a model that could be used in, for example, model-based path-following control. The starting point was the analytic support force calculation and the Magic Formula (MF) tire model with a reduced number of parameters developed previously at the research group.
The tire support force calculation was improved by allowing the center of mass (COM) location of the vehicle to change with respect to the wheels due to the orientation of the suspension. Also, the suspension cylinder forces were projected to tire support forces. The calculation of the rolling resistance moment was added to the MF model, which determines the torques of the wheels at constant-speed operation and cannot therefore be ignored. The components of the hydrostatic transmission (HST) were modeled using steady-state equations. The model also included the pressure dynamics in the hoses. The results from the tire forces and torques were combined into the wheel rotational dynamics to obtain a relationship between the torque from the HST and the tire force and torque from the MF model. In addition, the validity of the model needed to be tested for a whole new kind of driving structure, the skid-steer. The theory for modeling six-degrees-of-freedom (DoF) vehicle dynamics was presented but could not be validated at this stage due to poor accuracy.
The results proved good accuracy during pure longitudinal motion and reasonable accuracy on a curved trajectory. The experimental and simulated results from the Simscape Multibody model were compared for the trajectory and velocities of the vehicle. The analytic torques and angular speeds were validated with experimental data simultaneously. The results also presented the validity of the tire support force on uneven terrain. Overall, the dynamic vehicle model developed in the thesis could be used in designing model-based controls that improve the driving performance of heavy-duty mobile robots
Inter-System Negotiations Between Youth Psychiatry and Child Protection: A Study on Responding to the Many and Complex Needs of Young People
No full textThe study examined how the dialogues and distractions of inter-system negotiations between two separate yet interconnected systems of youth psychiatry and child protection arise once an adolescent is simultaneously receiving youth psychiatric treatment and child protection care. The study also examined whether inter-system negotiations produce solutions for the many and complex needs of adolescents based on 81 youth psychiatric patient case documents subjected to thematic analysis. The reciprocal, informing, inquiring, and ensuring dialogues were used to address 80 cases. The distractive dialogues revealed unsolved needs of an adolescent. Altogether, system-level factors can affect the treatment and care offered for adolescents.Peer reviewe
Innovative Approaches to Strengthening Postdoctoral Mentorship in Resource-Constrained African Universities
No full textThis study investigates innovative strategies to improve postdoctoral mentorship in resource-limited African universities, addressing significant challenges in establishing effective mentorship structures. A comprehensive literature review using PubMed, Scopus, Web of Science, AJOL, and Google Scholar, along with case studies from academic publications and institutional reports, was conducted. Thematic analysis identified challenges, best practices, and novel approaches. The review highlights effective methods to enhance mentorship programs, advocating for a reassessment of mentorship practices in African universities, and emphasizes mentorship models, collaborative frameworks, and technological applications. The study stresses the importance of innovative mentorship strategies to support early-career researchers in resource-constrained environments, offering insights for policymakers and academic leaders to bolster research capacity.Peer reviewe
Visuality as an Affordance on Instagram News Production
No full textNews media organisations have turned to social media platforms to engage with younger audiences who mainly consume news through these channels. This article focuses on news production on Instagram and explores visuality as a necessity and an affordance in producing journalistic content to the platform. Our data comprises of thematic interviews with social media professionals as well as Instagram Posts and video Reels from news media accounts from Finland. Through qualitative content analysis we have recognised three thematic categories that are connected to visuality guiding the professional decision making: 1) adaptation (strategic adaptation to the platform), 2) condensing (simplifying and shortening the news content) and 3) attention gaining (a strong selectivity targeting specific audiences). Finally, the identification of image-dominated news suggests that visual social media news stories possess characteristics of a new journalistic genre.Peer reviewe
Effect of cracks on the load-carrying capacity of glulam
No full textEngineered wood products (EWPs) may be prone to cracking though the impact of these cracks varies depending on the specific product. The impact of existing cracks on the structural behaviour of different EWPs is potentially detrimental in practical applications but has not been sufficiently studied. To meet the challenge, the primary objective of this study is to investigate the influence of crack length and location on the load-bearing capacity of glulam. Over 50 glulam beams with 10 different initial cracks were tested. The examined cracks were artificially induced delaminations of different lengths located in the middle of the beam's cross-section. Based on the findings, the length of the crack has an impact on the shear strength of the beam, but less than expected in the light of a simplified structural analysis that incorporates the crack into the effective width of the cross-section. Additionally, the crack length importance is connected to the stress state along the crack. The practical use of this study lies in improving the structural reliability of glulam by understanding how crack parameters affect the loadbearing capacity. As the main conclusions of the study, practical guidelines for the assessment of the load-bearing capacity of glulam with existing cracks were given.Peer reviewe