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Decoding the role of pre-existing austenite in transformation pathways during slow heating of cold-rolled medium-Mn steel for process design
No full textAbstract
This study reveals a previously unreported transformation pathway governing austenite evolution during slow continuous heating of cold-rolled medium-Mn steel (Fe–0.4C–6Mn–2Al–1Si–0.05Nb, wt.%). Using a correlative approach combining in-situ high-energy X-ray diffraction, electron microscopy, atom probe tomography, and DICTRA simulations, we demonstrate that introducing a considerable amount of pre-existing austenite (γpre) at the onset of the intercritical annealing region is beneficial for microstructural control which acts as both a solute reservoir and a structural template for the formation of newly formed austenite (γnew). Upon heating between 500 and 800 °C, fine (Fe, Mn)-rich carbides precipitate from γpre, serving as heterogeneous nucleation sites for γnew while concurrently depleting C and Mn from γpre. The subsequent dissolution of these carbides above ~ 660 °C releases solutes into the surrounding matrix, driving localized partitioning and stabilizing γnew. This process results in a bimodal microstructure comprising elongated, low-alloy γpre and blocky, high-alloy γnew embedded in a submicron ferritic matrix. At higher temperatures, solute dilution reduces austenite stability. A retained austenite of 55 vol% was achieved at 780 °C, consistent with thermodynamic predictions without prolonged isothermal holding. These findings establish the controlled decomposition–reconstruction of γpre into γnew as a viable strategy for tailoring austenite morphology and chemistry, enabling efficient stabilization of high retained austenite amounts in medium-Mn steels while minimizing alloying requirements.Abstract
This study reveals a previously unreported transformation pathway governing austenite evolution during slow continuous heating of cold-rolled medium-Mn steel (Fe–0.4C–6Mn–2Al–1Si–0.05Nb, wt.%). Using a correlative approach combining in-situ high-energy X-ray diffraction, electron microscopy, atom probe tomography, and DICTRA simulations, we demonstrate that introducing a considerable amount of pre-existing austenite (γpre) at the onset of the intercritical annealing region is beneficial for microstructural control which acts as both a solute reservoir and a structural template for the formation of newly formed austenite (γnew). Upon heating between 500 and 800 °C, fine (Fe, Mn)-rich carbides precipitate from γpre, serving as heterogeneous nucleation sites for γnew while concurrently depleting C and Mn from γpre. The subsequent dissolution of these carbides above ~ 660 °C releases solutes into the surrounding matrix, driving localized partitioning and stabilizing γnew. This process results in a bimodal microstructure comprising elongated, low-alloy γpre and blocky, high-alloy γnew embedded in a submicron ferritic matrix. At higher temperatures, solute dilution reduces austenite stability. A retained austenite of 55 vol% was achieved at 780 °C, consistent with thermodynamic predictions without prolonged isothermal holding. These findings establish the controlled decomposition–reconstruction of γpre into γnew as a viable strategy for tailoring austenite morphology and chemistry, enabling efficient stabilization of high retained austenite amounts in medium-Mn steels while minimizing alloying requirements
A Living Lab-inspired Double Diamond approach to co-creating cross-border rural digital policy
No full textThis article explores the development of a cross-border rural digital policy using a Living Lab inspired Double Diamond approach in the Muodoslompolo (Sweden) and Muonio (Finland) region. The study combines participatory, speculative, and critical design methods with structured stakeholder engagement through the PentaHelix model. Empirical data were collected through an interdisciplinary researcher workshop, a field visit involving interviews and a focus group with local residents, and a semi-structured focus group with seven international Living Lab practitioners conducted at the Open Living Lab Days 2025 conference. The research process followed the four phases of the Double Diamond model: Discover, Define, Develop, and Deliver. The findings highlight the importance of trust-based facilitation, informal communication practices, and institutional learning in co-creating policy in rural settings. A draft policy framework was produced, including a prioritization matrix aligned with relevant Sustainable Development Goals (SDGs), thematic policy domains, and a set of participatory working methods. The study contributes to Living Lab literature by demonstrating the application of LL principles in rural, cross-border policy contexts and offers a transferable methodology for inclusive digital policy development in underrepresented regions.This article explores the development of a cross-border rural digital policy using a Living Lab inspired Double Diamond approach in the Muodoslompolo (Sweden) and Muonio (Finland) region. The study combines participatory, speculative, and critical design methods with structured stakeholder engagement through the PentaHelix model. Empirical data were collected through an interdisciplinary researcher workshop, a field visit involving interviews and a focus group with local residents, and a semi-structured focus group with seven international Living Lab practitioners conducted at the Open Living Lab Days 2025 conference. The research process followed the four phases of the Double Diamond model: Discover, Define, Develop, and Deliver. The findings highlight the importance of trust-based facilitation, informal communication practices, and institutional learning in co-creating policy in rural settings. A draft policy framework was produced, including a prioritization matrix aligned with relevant Sustainable Development Goals (SDGs), thematic policy domains, and a set of participatory working methods. The study contributes to Living Lab literature by demonstrating the application of LL principles in rural, cross-border policy contexts and offers a transferable methodology for inclusive digital policy development in underrepresented regions
Assisted living in relation to use of psychiatric inpatient and outpatient care - a 23-year time-trend analysis of national indicators from Finland
No full textAbstract
Dehospitalization for people with severe mental illness (SMI) has continued for decades and led to the development of assisted living (AL) services. However, there is little knowledge on how the increasing use of AL services relates to the time trends of different psychiatric services. This study utilizes a 23-year time series data from Finland to evaluate the use of AL services in relation to the use of psychiatric inpatient and specialized psychiatric outpatient care. This population-based data from 1996 to 2018 was extracted from the Sotkanet Statistics and Indicator Bank, administered by the Finnish Institute for Health and Welfare (THL). The analyses of the time trends in different levels of psychiatric AL services, classified according to support given to AL habitants, was possible to perform from the year 2006 onwards. The Joinpoint Regression analysis was applied to estimate time trends of the indicators selected for our study. In the whole 23-year study period, an increased rate of habitants in psychiatric AL services was correlated with an increased number of specialized psychiatric outpatient visits (r = 0.766, p<0.001), and decreased rates of psychiatric inpatient care days (r = - 0.970, p<0.001). The increase in the use of psychiatric AL services appeared mainly in lighter AL services (less support provided) that accounted for increased rates of habitants in service housing and supported accommodation. Our results showed that dehospitalization has increased the need for AL services drastically, but the increase in the use of specialized psychiatric outpatient care was clearly slower than the growth of AL services or the decrease in psychiatric inpatient treatment. The rise of lighter AL services seemed to occur while heavily supported AL services remained stagnant, but the reasons behind it need further research.Abstract
Dehospitalization for people with severe mental illness (SMI) has continued for decades and led to the development of assisted living (AL) services. However, there is little knowledge on how the increasing use of AL services relates to the time trends of different psychiatric services. This study utilizes a 23-year time series data from Finland to evaluate the use of AL services in relation to the use of psychiatric inpatient and specialized psychiatric outpatient care. This population-based data from 1996 to 2018 was extracted from the Sotkanet Statistics and Indicator Bank, administered by the Finnish Institute for Health and Welfare (THL). The analyses of the time trends in different levels of psychiatric AL services, classified according to support given to AL habitants, was possible to perform from the year 2006 onwards. The Joinpoint Regression analysis was applied to estimate time trends of the indicators selected for our study. In the whole 23-year study period, an increased rate of habitants in psychiatric AL services was correlated with an increased number of specialized psychiatric outpatient visits (r = 0.766, p<0.001), and decreased rates of psychiatric inpatient care days (r = - 0.970, p<0.001). The increase in the use of psychiatric AL services appeared mainly in lighter AL services (less support provided) that accounted for increased rates of habitants in service housing and supported accommodation. Our results showed that dehospitalization has increased the need for AL services drastically, but the increase in the use of specialized psychiatric outpatient care was clearly slower than the growth of AL services or the decrease in psychiatric inpatient treatment. The rise of lighter AL services seemed to occur while heavily supported AL services remained stagnant, but the reasons behind it need further research
Protocol for a participatory survey to investigate the long-term effectiveness of adult psychiatric services (PSILEAPS) : a prospective exploratory cohort study
No full textAbstract
Mental health research and practice is currently moving beyond a focus on group-level symptom reduction models. Hence, research and treatment increasingly emphasize the real-life individual needs of service users and their social networks. One example is the Open Dialogue approach (OD), which has demonstrated promising outcomes in the Finnish Western Lapland (WL) catchment area. Nevertheless, it is unclear how OD-based services have so far been maintained in WL. It is also unclear how the experiences of multi disciplinary care teams, service users and their social network members differ, with regard to differing approaches to mental health treatment. More generally, there is a global need for information on factors associated with the long-term treatment outcomes of real-world mental healthcare. This project – a participatory survey to investigate the long-term effectiveness of adult psychiatric services (PSILEAPS) – aims to address these questions. The survey will take place over a two-week period. It will be aimed at all five WL catchment area adult mental health units, and will cover care team members, service users and members of their social network. These will be asked to share their thoughts on (i) why mental health services have been needed in the case in question, and (ii) what factors in the treatment have been helpful or unhelpful. The service users who participate will form a research cohort, which will be followed over five years. Information on demographic and clinical characteristics will be obtained from social and healthcare registers at baseline, and at two- and five-year follow-ups. The primary outcome variables at follow-up will be treatment contact at follow-up, disability allowance at follow-up and death during follow-up. Exploratory statistical analyses will be used to study how different variables (including the main principles of OD) are associated with different outcomes. The information can be used to create new hypotheses to guide future research, and to develop mental health services. The participatory design will enable service users to join in the co-production of knowledge. This has the potential to immediately guide and improve their mental healthcare.Abstract
Mental health research and practice is currently moving beyond a focus on group-level symptom reduction models. Hence, research and treatment increasingly emphasize the real-life individual needs of service users and their social networks. One example is the Open Dialogue approach (OD), which has demonstrated promising outcomes in the Finnish Western Lapland (WL) catchment area. Nevertheless, it is unclear how OD-based services have so far been maintained in WL. It is also unclear how the experiences of multi disciplinary care teams, service users and their social network members differ, with regard to differing approaches to mental health treatment. More generally, there is a global need for information on factors associated with the long-term treatment outcomes of real-world mental healthcare. This project – a participatory survey to investigate the long-term effectiveness of adult psychiatric services (PSILEAPS) – aims to address these questions. The survey will take place over a two-week period. It will be aimed at all five WL catchment area adult mental health units, and will cover care team members, service users and members of their social network. These will be asked to share their thoughts on (i) why mental health services have been needed in the case in question, and (ii) what factors in the treatment have been helpful or unhelpful. The service users who participate will form a research cohort, which will be followed over five years. Information on demographic and clinical characteristics will be obtained from social and healthcare registers at baseline, and at two- and five-year follow-ups. The primary outcome variables at follow-up will be treatment contact at follow-up, disability allowance at follow-up and death during follow-up. Exploratory statistical analyses will be used to study how different variables (including the main principles of OD) are associated with different outcomes. The information can be used to create new hypotheses to guide future research, and to develop mental health services. The participatory design will enable service users to join in the co-production of knowledge. This has the potential to immediately guide and improve their mental healthcare
Full-Duplex D2D Communication via Active RIS: Performance Under System Imperfections
No full textAbstract
Active reconfigurable intelligent surface (RIS) technology strengthens the impinging signal to counteract the multiplicative fading effects associated with conventional passive RIS implementations. This letter studies the performance of an active RIS-assisted full-duplex device-to-device communication with discrete phase shifts, transceiver hardware impairments (HIs), and residual self-interference (RSI) imperfections. Closed-form expressions for the outage probability, ergodic capacity, and symbol error rate are derived using the Gaussian Chebyshev quadrature approximation. The system performance is evaluated in comparison with that of a passive RIS and hybrid RIS. We demonstrate that transceiver HIs and RSI limit system performance, with HIs being particularly restrictive at higher target data rates. Finally, Monte Carlo simulations are conducted to validate the derived expressions.Abstract
Active reconfigurable intelligent surface (RIS) technology strengthens the impinging signal to counteract the multiplicative fading effects associated with conventional passive RIS implementations. This letter studies the performance of an active RIS-assisted full-duplex device-to-device communication with discrete phase shifts, transceiver hardware impairments (HIs), and residual self-interference (RSI) imperfections. Closed-form expressions for the outage probability, ergodic capacity, and symbol error rate are derived using the Gaussian Chebyshev quadrature approximation. The system performance is evaluated in comparison with that of a passive RIS and hybrid RIS. We demonstrate that transceiver HIs and RSI limit system performance, with HIs being particularly restrictive at higher target data rates. Finally, Monte Carlo simulations are conducted to validate the derived expressions
Intense solar radiation constrains plant species richness in global grasslands
No full textAbstract
The search for predictors of plant diversity has challenged scientists for decades. Here we identify intense photosynthetically active radiation (PAR) as a major factor constraining plant species richness in global grasslands. We show that the strength of the negative relationship between species richness and PAR increases with increasing elevation and that species richness is more strongly correlated with intense PAR than with UV-B radiation, climate variables, and atmospheric nitrogen deposition. In addition to species richness, plant biomass was also negatively correlated with PAR at higher elevations, indicating that intense PAR also constrains plant biomass in montane grasslands. Furthermore, we show that the decrease in plant species richness with increasing PAR is mainly caused by a decrease in species richness of forbs, sedges, and rushes. In contrast, species richness of grasses was only negatively correlated with PAR at high elevations, and species richness of legumes was not significantly correlated with PAR. Our results suggest that PAR constrains plant species richness in global grasslands and limits the extent to which plant species of specific functional groups can migrate uphill in response to climate warming.Abstract
The search for predictors of plant diversity has challenged scientists for decades. Here we identify intense photosynthetically active radiation (PAR) as a major factor constraining plant species richness in global grasslands. We show that the strength of the negative relationship between species richness and PAR increases with increasing elevation and that species richness is more strongly correlated with intense PAR than with UV-B radiation, climate variables, and atmospheric nitrogen deposition. In addition to species richness, plant biomass was also negatively correlated with PAR at higher elevations, indicating that intense PAR also constrains plant biomass in montane grasslands. Furthermore, we show that the decrease in plant species richness with increasing PAR is mainly caused by a decrease in species richness of forbs, sedges, and rushes. In contrast, species richness of grasses was only negatively correlated with PAR at high elevations, and species richness of legumes was not significantly correlated with PAR. Our results suggest that PAR constrains plant species richness in global grasslands and limits the extent to which plant species of specific functional groups can migrate uphill in response to climate warming
Kasvukauden lämpöolojen ja fenologisten vaiheiden spatiaalinen ja ajallinen arviointi neljälle merkittävälle viljelykasville Suomessa (1961–2023)
No full textClimate-induced shifts in temperature regimes impose substantial influences on hydrological processes, agricultural productivity, and ecosystem stability. Variations in thermal conditions can alter germination, flowering, and maturation, thereby enhancing or hindering crop yields, depending on the crop and local climate. To effectively evaluate the implications of climate change for agriculture, it is crucial to understand how temperature dynamics spatiotemporally evolve. This study investigates long-term trends in Growing Degree Days (GDD) across Finland over the period 1961- 2023, focusing on spatial and temporal variations in heat accumulation and their impacts on crop development. Daily mean temperature data, collected at 10-kilometer resolution by the Finnish Meteorological Institute, were analyzed using an analytical framework. Specific emergence and stage-wise GDD thresholds were established for four major crops in Finland: faba beans, spring barley, spring oats, and winter wheat. Additionally, thermal conditions were evaluated using a seven-class temperature index and Compound Extreme Indices (CEI). Long-term trends in GDD, thermal classes, and CEI were evaluated using the Mann–Kendall trend test, while phenological shifts were assessed using two-sample t-tests. The results indicate a significant increase in GDD across all regions (p ≤ 0.001), with Northern Finland showing the largest increase due to a delayed end of the growing season. By the 2000s, GDD levels surpassed maturity thresholds for all the crops, while phenological trends displayed earlier starts of the growing season (SOS) and later ends of the season (EOS), effectively lengthening the growing season. Overall, changes in thermal classes reflected a decrease in cold-stress days and an increase in optimal and mild heat conditions, emphasizing a northward shift in the suitability for crop production
Simulating thermo-mechanical and microstructural phenomena in a laboratory-scale hot rolling mill
No full textAbstract
Developing and validating metallurgical models for microstructural evolution during hot rolling was the aim of this work. In earlier studies recrystallization and grain growth have been simulated and combined with the academic version of the Virtual Rolling Mill, and in this study the models are further improved and compared to experimental data. The effect of Nb-C precipitation is also studied by comparing a niobium-containing steel with a mildly alloyed steel. Accurate information is needed for hot rolling in a controlled environment to obtain reliable experimental data. For that, a laboratory-scale hot rolling mill and thermo-mechanical simulator were used. Hot rolling experiments have been conducted in this study, and the model results have been compared to the experimental results. The comparison showed good correspondence, and the model set was validated successfully.Abstract
Developing and validating metallurgical models for microstructural evolution during hot rolling was the aim of this work. In earlier studies recrystallization and grain growth have been simulated and combined with the academic version of the Virtual Rolling Mill, and in this study the models are further improved and compared to experimental data. The effect of Nb-C precipitation is also studied by comparing a niobium-containing steel with a mildly alloyed steel. Accurate information is needed for hot rolling in a controlled environment to obtain reliable experimental data. For that, a laboratory-scale hot rolling mill and thermo-mechanical simulator were used. Hot rolling experiments have been conducted in this study, and the model results have been compared to the experimental results. The comparison showed good correspondence, and the model set was validated successfully