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New Insight into the Reactivity of Steel Slags: Effect of Post-milling Duration
No full textAbstract
Incorporating steel slag, a residue derived from the metallurgical industry, into cementitious systems offers a sustainable route for resource recovery and carbon footprint reduction. Milling has been reported to address the low cementitious reactivity of steel slag, which remains a significant barrier to its widespread adoption. However, the influence of storage duration after milling on steel slag performance has not been systematically evaluated. To investigate the effects of post-milling duration as an independent factor, two types of steel slag, derived from a basic oxygen furnace and an electric arc furnace processes, were milled using planetary ball milling and stored under controlled environmental conditions for 1 h, 1 day, 4 days, 7 days, 3 months, and 1 year. The results showed that prolonged storage caused significant particle agglomeration, detected by particle size analysis, and a slight reduction in reactivity after 1 year, as determined by the Rapid, Reliable Relevant (R3) reactivity test for supplementary cementitious materials. Replacing 30% of cement with steel slags stored for different times (1 h vs. 1 year) changed the properties of the blends. Compared with freshly milled slag, slag stored for 1 year caused a slight delay in cement hydration, as evidenced by calorimetry results. Consequently, blends containing 1-year-stored slag exhibited prolonged setting times and reduced apparent viscosity compared with the 1-h slag–cement blends. The compressive strength of blended cements was also negatively affected by long-term storage, and the amount of hydration products, such as portlandite, was slightly reduced in 28-day composites containing 1-year-stored slag.Abstract
Incorporating steel slag, a residue derived from the metallurgical industry, into cementitious systems offers a sustainable route for resource recovery and carbon footprint reduction. Milling has been reported to address the low cementitious reactivity of steel slag, which remains a significant barrier to its widespread adoption. However, the influence of storage duration after milling on steel slag performance has not been systematically evaluated. To investigate the effects of post-milling duration as an independent factor, two types of steel slag, derived from a basic oxygen furnace and an electric arc furnace processes, were milled using planetary ball milling and stored under controlled environmental conditions for 1 h, 1 day, 4 days, 7 days, 3 months, and 1 year. The results showed that prolonged storage caused significant particle agglomeration, detected by particle size analysis, and a slight reduction in reactivity after 1 year, as determined by the Rapid, Reliable Relevant (R3) reactivity test for supplementary cementitious materials. Replacing 30% of cement with steel slags stored for different times (1 h vs. 1 year) changed the properties of the blends. Compared with freshly milled slag, slag stored for 1 year caused a slight delay in cement hydration, as evidenced by calorimetry results. Consequently, blends containing 1-year-stored slag exhibited prolonged setting times and reduced apparent viscosity compared with the 1-h slag–cement blends. The compressive strength of blended cements was also negatively affected by long-term storage, and the amount of hydration products, such as portlandite, was slightly reduced in 28-day composites containing 1-year-stored slag
Synergistic Effects in Matrix-Embedded Alloy Nanoclusters: Advanced Type-I Photosensitizers for Theranostics
No full textAbstract
A combination of biomedical imaging and photodynamic therapy (PDT) in a single nanomaterial would be a breakthrough in nanomedicine. However, devising a single photosensitizer capable of efficient PDT without requiring an external oxygen source under typically hypoxic tumor conditions, combined with high photostability, biocompatibility, and renal clearance, remains a challenge. Atomically precise ultrasmall (<2 nm) gold nanoclusters (AuNCs) are emerging as potential multifunctional biomedicines, encompassing imaging, diagnosis, and therapy in a single nanoplatform. Herein, we report bioderived cellulose nanocrystal-supported gold nanoclusters (CNC-AuNCs) with selective mono or multiheteroatom (Ag, Pd, and Pt) substitution at the core of the nanoclusters. The replacement of one or more gold atoms significantly modulates their emission wavelengths, photoluminescence quantum yields, as well as excited-state relaxation kinetics. These materials can easily penetrate the cells, accumulating in the cytoplasm and emitting bright luminescence. While the nanocomposites are highly biocompatible, they can produce reactive oxygen species (ROS) through the formation of free radicals (O2–· and ·OH) upon exposure of light. The synergistic effect of the light absorption by the matrix and the diverse excited-state relaxation pathways of the nanoclusters results in the efficient generation of ROS in variable concentrations, ultimately leading to the complete destruction of targeted cancer cells via Type-I photodynamic effect. The optimal ROS efficacy combined with minimal cytotoxicity suggests a universal strategy for developing strong PDT-I agents, paving the way for versatile nanomaterials in theranostic applications.Abstract
A combination of biomedical imaging and photodynamic therapy (PDT) in a single nanomaterial would be a breakthrough in nanomedicine. However, devising a single photosensitizer capable of efficient PDT without requiring an external oxygen source under typically hypoxic tumor conditions, combined with high photostability, biocompatibility, and renal clearance, remains a challenge. Atomically precise ultrasmall (<2 nm) gold nanoclusters (AuNCs) are emerging as potential multifunctional biomedicines, encompassing imaging, diagnosis, and therapy in a single nanoplatform. Herein, we report bioderived cellulose nanocrystal-supported gold nanoclusters (CNC-AuNCs) with selective mono or multiheteroatom (Ag, Pd, and Pt) substitution at the core of the nanoclusters. The replacement of one or more gold atoms significantly modulates their emission wavelengths, photoluminescence quantum yields, as well as excited-state relaxation kinetics. These materials can easily penetrate the cells, accumulating in the cytoplasm and emitting bright luminescence. While the nanocomposites are highly biocompatible, they can produce reactive oxygen species (ROS) through the formation of free radicals (O2–· and ·OH) upon exposure of light. The synergistic effect of the light absorption by the matrix and the diverse excited-state relaxation pathways of the nanoclusters results in the efficient generation of ROS in variable concentrations, ultimately leading to the complete destruction of targeted cancer cells via Type-I photodynamic effect. The optimal ROS efficacy combined with minimal cytotoxicity suggests a universal strategy for developing strong PDT-I agents, paving the way for versatile nanomaterials in theranostic applications
NLRP3‐Caspase‐1 Axis in Human Adipose Tissue Crown‐Like Structures: A Potential Mediator of Inflammation and the Effects of Bariatric Surgery
No full textAbstract
Background:
Obesity-related comorbidities, such as type 2 diabetes, are associated with chronic inflammation mediated by macrophages. This inflammation is characterized by the accumulation of macrophages in crown-like structures (CLS) surrounding dead adipocytes within adipose tissue. In a recent study, we reported a significant reduction in CLS-associated macrophages following bariatric surgery. The NLRP3 inflammasome and its downstream effector, Caspase-1, are well-established mediators of metabolic dysfunction and inflammation in obesity.
Methods:
Immunohistochemical single- and multiplex staining of subcutaneous adipose tissue (SAT) samples from patients with obesity was performed to characterize the detailed distribution of NLRP3 and Caspase-1. The samples were collected during gastric bypass surgery and at a 1-year follow-up.
:
Results:
Both NLRP3 and Caspase-1 were expressed by CD68-positive macrophages in SAT including both single macrophages and those forming CLS. A reduction in the total number of SAT macrophages expressing these proteins was detected following gastric bypass. Furthermore, NLRP3 and Caspse-1 were observed in the endothelium of vascular structures.
Conclusions:
Our findings demonstrate that both CLS-forming and single cell macrophage populations in human adipose tissue express NLRP3 and Caspase-1. The study highlights the significance of the NLRP3 inflammasome macrophages in the pathogenesis of adipose tissue inflammation in obesity. The previously reported abundance of CLS in untreated obesity and their reduction after bariatric surgery suggest that the NLRP3-Caspase-1 axis within CLS may serve as an important mediator of the beneficial metabolic effects associated with bariatric surgery.Abstract
Background:
Obesity-related comorbidities, such as type 2 diabetes, are associated with chronic inflammation mediated by macrophages. This inflammation is characterized by the accumulation of macrophages in crown-like structures (CLS) surrounding dead adipocytes within adipose tissue. In a recent study, we reported a significant reduction in CLS-associated macrophages following bariatric surgery. The NLRP3 inflammasome and its downstream effector, Caspase-1, are well-established mediators of metabolic dysfunction and inflammation in obesity.
Methods:
Immunohistochemical single- and multiplex staining of subcutaneous adipose tissue (SAT) samples from patients with obesity was performed to characterize the detailed distribution of NLRP3 and Caspase-1. The samples were collected during gastric bypass surgery and at a 1-year follow-up.
:
Results:
Both NLRP3 and Caspase-1 were expressed by CD68-positive macrophages in SAT including both single macrophages and those forming CLS. A reduction in the total number of SAT macrophages expressing these proteins was detected following gastric bypass. Furthermore, NLRP3 and Caspse-1 were observed in the endothelium of vascular structures.
Conclusions:
Our findings demonstrate that both CLS-forming and single cell macrophage populations in human adipose tissue express NLRP3 and Caspase-1. The study highlights the significance of the NLRP3 inflammasome macrophages in the pathogenesis of adipose tissue inflammation in obesity. The previously reported abundance of CLS in untreated obesity and their reduction after bariatric surgery suggest that the NLRP3-Caspase-1 axis within CLS may serve as an important mediator of the beneficial metabolic effects associated with bariatric surgery
Enhancing Upper Secondary Students' Situational Engagement and Cognitive Prerequisites of Learning Through the Physically Active Academic Lessons Intervention: Protocol for a Mixed Methods Cluster Randomized Individual Crossover Trial
No full textAbstract
Background:
Internationally, physical activity is successfully integrated into academic lessons in primary schools, showing promising results on cognition and student engagement. However, there is a lack of knowledge about its effects and feasibility for individual situated learning processes in upper secondary school.
Objective:
This protocol describes the design and methods of the Physically Active Academic Lessons (PAAL) study, a mixed methods, cluster randomized, individual crossover trial. The PAAL study aims to examine the acute effects of physically active academic lessons on cognitive prerequisites of learning (alertness and executive functions) and situational engagement (behavioral, cognitive, and emotional engagement; disaffection; competence experiences; and help seeking), as well as factors modifying these effects (physical and mental load and perceived physical and academic competence). Further, subject teachers’ and students’ experiences and perceptions of physically active academic lessons in general upper secondary school will be explored.
Methods:
The first part of the PAAL study involves exploring subject teachers’ experiences of facilitators, barriers, usefulness, and the meaning of physically active academic lessons for the situational learning process through semistructured interviews with 14 teachers. The second part consists of a cluster‑randomized individual crossover trial including 168 students in mathematics and foreign language lessons, followed by interviews with 30 students.
Results:
Funding for the study was obtained in May 2023. Ethical approval for the teacher interviews was granted in September 2023, and for the student trial in December 2023. Data collection was completed between October 2023 and November 2024. Data analysis is ongoing. The findings of the study will provide essential evidence-based information on physically active classroom practices that support teachers and schools in implementing pedagogical methods that enhance student learning and well-being in upper secondary schools.
Conclusions:
The background, design, content of the intervention, and methods of the PAAL study are presented. This study aims to address a gap in the literature regarding the feasibility and effectiveness of physically active methods during academic lessons in upper secondary school.
Trial Registration:
ISRCTN 63809854; http://www.controlled-trials.com/ISRCTN63809854/63809854
International Registered Report Identifier (IRRID):
RR1-10.2196/84601
JMIR Res Protoc 2026;15:e84601Abstract
Background:
Internationally, physical activity is successfully integrated into academic lessons in primary schools, showing promising results on cognition and student engagement. However, there is a lack of knowledge about its effects and feasibility for individual situated learning processes in upper secondary school.
Objective:
This protocol describes the design and methods of the Physically Active Academic Lessons (PAAL) study, a mixed methods, cluster randomized, individual crossover trial. The PAAL study aims to examine the acute effects of physically active academic lessons on cognitive prerequisites of learning (alertness and executive functions) and situational engagement (behavioral, cognitive, and emotional engagement; disaffection; competence experiences; and help seeking), as well as factors modifying these effects (physical and mental load and perceived physical and academic competence). Further, subject teachers’ and students’ experiences and perceptions of physically active academic lessons in general upper secondary school will be explored.
Methods:
The first part of the PAAL study involves exploring subject teachers’ experiences of facilitators, barriers, usefulness, and the meaning of physically active academic lessons for the situational learning process through semistructured interviews with 14 teachers. The second part consists of a cluster‑randomized individual crossover trial including 168 students in mathematics and foreign language lessons, followed by interviews with 30 students.
Results:
Funding for the study was obtained in May 2023. Ethical approval for the teacher interviews was granted in September 2023, and for the student trial in December 2023. Data collection was completed between October 2023 and November 2024. Data analysis is ongoing. The findings of the study will provide essential evidence-based information on physically active classroom practices that support teachers and schools in implementing pedagogical methods that enhance student learning and well-being in upper secondary schools.
Conclusions:
The background, design, content of the intervention, and methods of the PAAL study are presented. This study aims to address a gap in the literature regarding the feasibility and effectiveness of physically active methods during academic lessons in upper secondary school.
Trial Registration:
ISRCTN 63809854; http://www.controlled-trials.com/ISRCTN63809854/63809854
International Registered Report Identifier (IRRID):
RR1-10.2196/84601
JMIR Res Protoc 2026;15:e8460
Development and evaluation of artificial intelligence literacy training for teacher education students
No full textAbstract
Teacher education students play double role as present learners and future educators. Hence, they need targeted training to navigate the growing influence of Generative Artificial Intelligence (GenAI) on teaching, learning and professional identity. However, existing artificial intelligence (AI) literacy programmes predominantly emphasize technical AI knowledge and pre-GenAI tools or are offered by GenAI platforms that focus on their own technologies' features, thereby lacking pedagogically structured frameworks that address non-technical dimensions such as ethics, contextual understanding and the development of human-centered, critical and lifelong learning mindsets to adapt to rapid technology changes. Furthermore, limitation of time in teacher education syllabus and faculty's lack of AI literacy require targeted intervention. This design-based research (DBR) aims to fill this gap by developing and evaluating a set of design principles for GenAI literacy training in teacher education. Integrating contemporary AI competency frameworks for learners and teachers, the study implements these principles in a workshop that serves as the research prototype. The prototype was first piloted with 14 master's students and then evaluated with 29 teacher education (TE) students. Results show significant gains in participants' AI competence self-efficacy, attitudes towards GenAI and commitment to critical, ethical and pedagogical engagement with GenAI tools. The findings highlight the need for teacher education programmes to integrate GenAI literacy that supports teachers' evolving roles as reflective practitioners, co-creators and lifelong learners in an AI-driven world.Abstract
Teacher education students play double role as present learners and future educators. Hence, they need targeted training to navigate the growing influence of Generative Artificial Intelligence (GenAI) on teaching, learning and professional identity. However, existing artificial intelligence (AI) literacy programmes predominantly emphasize technical AI knowledge and pre-GenAI tools or are offered by GenAI platforms that focus on their own technologies' features, thereby lacking pedagogically structured frameworks that address non-technical dimensions such as ethics, contextual understanding and the development of human-centered, critical and lifelong learning mindsets to adapt to rapid technology changes. Furthermore, limitation of time in teacher education syllabus and faculty's lack of AI literacy require targeted intervention. This design-based research (DBR) aims to fill this gap by developing and evaluating a set of design principles for GenAI literacy training in teacher education. Integrating contemporary AI competency frameworks for learners and teachers, the study implements these principles in a workshop that serves as the research prototype. The prototype was first piloted with 14 master's students and then evaluated with 29 teacher education (TE) students. Results show significant gains in participants' AI competence self-efficacy, attitudes towards GenAI and commitment to critical, ethical and pedagogical engagement with GenAI tools. The findings highlight the need for teacher education programmes to integrate GenAI literacy that supports teachers' evolving roles as reflective practitioners, co-creators and lifelong learners in an AI-driven world
How to implement learning analytics with agency in mind : perspectives of higher education stakeholders
No full textAbstract
Learning analytics (LA) has shown considerable potential to support higher education (HE) students’ agency, which is defined as individuals’ proactive, self-initiated thoughts and actions that guide their learning. However, research has primarily focused on short-term or course-level applications, and evidence remains limited on how student agency manifests in the broader academic path context when supported by LA.
While LA can provide valuable support once in use, its life cycle—from development to adoption into everyday practice—is rarely straightforward. Instead, HE institutions are complex environments composed of diverse agents with varying perspectives, making LA implementation a multilayered process shaped by multiple perspectives and priorities.
To address these complexities, this article-based dissertation adopts a multistakeholder viewpoint, drawing on the experiences and views of multiple groups. It examines three interrelated levels: LA user experiences (micro), stakeholder perceptions and practices (mezzo), and institutional conditions (macro). The social cognitive perspective on agency forms the primary theoretical foundation, while complexity leadership and transformative agency approaches are employed complementarily to address mezzo- and macro-level dynamics.
A case institution implementing an LA dashboard for students and staff was investigated using a mixed-method approach (N = 127). The first study explored LA developers’ perceptions of how LA can support students; the second examined students’ perceptions of agency support provided by the dashboard over an academic year; and the third focused on staff perspectives regarding institutional enablers and barriers to implementation.
The findings indicate that LA supported student agency primarily by enhancing self-regulatory activities and decision-making. In the development context, student agency was defined as meaningful involvement and participation in decision-making. Across stakeholder and institutional levels, active participation, clear accountabilities, and the identification of actionable insights were critical for successful implementation. The findings extend our theoretical understanding through discussing agency in the LA context. In practice, the results inform institutional LA implementation and offer guidance for fostering stakeholder agency throughout the process. Original papers Kaveri, A., Silvola, A., & Muukkonen, H. (2023). Supporting student agency with a student-facing learning analytics dashboard: Perceptions of an interdisciplinary development team. Journal of Learning Analytics, 10(2), 85–99. https://doi.org/10.18608/jla.2023.7729 https://doi.org/10.18608/jla.2023.7729 Self-archived version Kaveri, A., Celik, I., Gedrimiene, E., Silvola, A., & Muukkonen, H. (2026). Longitudinal effects of learning analytics support for study planning and monitoring: Role of self-efficacy and data literacy. Computers & Education, 246, 105532. https://doi.org/10.1016/j.compedu.2025.105532 https://doi.org/10.1016/j.compedu.2025.105532 Self-archived version Kaveri, A., Korpi, J., Silvola, A., & Muukkonen, H. (in press). Staff perspectives on key dimensions of institutional learning analytics implementation. Education and Information Technologies. https://doi.org/10.1007/s10639-025-13790-4 https://doi.org/10.1007/s10639-025-13790-4 Self-archived version Tiivistelmä
Oppimisanalytiikka mahdollistaa korkeakouluopiskelijoiden toimijuuden tukemisen esimerkiksi tarjoamalla tietoa itsereflektioon, opintojen seurantaan ja suunnitteluun. Tukea toimijuudelle on kuitenkin keskitytty tarjoamaan pääosin oppimistapahtuma- ja kurssitasoilla. Tietoa on rajallisesti siitä, miten oppimisanalytiikalla tuettu opiskelijatoimijuus muotoutuu opintopolkujen tasolla.
Vaikka käytettäessä oppimisanalytiikka voi tarjota opiskelijoille arvokasta tukea, sen elinkaari suunnittelusta käyttöönottoon ei ole suoraviivainen. Korkeakoulut ovat monimutkaisia ympäristöjä, joissa operoivat moninaiset toimijat. Täten myös oppimisanalytiikan käyttöönotto on monitasoinen prosessi, jota muokkaavat eri näkökulmat ja prioriteetit.
Näiden moninaisten näkökulmien ymmärtämiseksi, tässä artikkelipohjaisessa väitöskirjassa hyödynnettiin moninäkökulmaista lähestymistapaa. Tutkimuksessa tarkasteltiin tapauskorkeakoulua, jossa käyttöönotettiin opiskelijoille ja henkilökunnalle suunnattua oppimisanalytiikan työkalua. Eri sidosryhmien (N = 127) näkökulmia tutkittiin monimenetelmäisesti. Ensimmäinen osajulkaisu tarkasteli kehittäjien näkökulmia opiskelijatoimijuuden tukemisesta oppimisanalytiikalla. Toinen osajulkaisu tutki lukuvuoden ajan opiskelijoiden näkökulmia siitä, tukeeko oppimisanalytiikka heidän toimijuuttaan. Kolmannessa osajulkaisussa keskityttiin korkeakoulun henkilökunnan näkökulmiin työkalun käyttöönotosta instituutiotasolla.
Opiskelijoiden osalta todettiin, että oppimisanalytiikka tuki toimijuutta lisäämällä mahdollisuuksia itsesäätelyyn opinnoissa ja tukemalla päätöksentekoa. Oppimisanalytiikan kehitystyössä opiskelijatoimijuus määriteltiin osallistumisena esimerkiksi päätöksentekoon. Henkilökunnan ja instituutiotason kannalta keskeisiksi nousivat sidosryhmien mukaanotto käyttöönottoprosesseihin sekä sen selkeyttäminen, mitä vastuita ja rooleja eri ryhmillä prosessissa on, ja mitä toiminnallista tietoa työkalu tarjoaa.
Tulokset laajentavat teoreettista ymmärrystämme toimijuudesta esittelemällä oppimisanalytiikan kontekstin. Käytännön tasolle tutkimustulokset tarjoavat tietoa oppimisanalytiikan käyttöönottoprosesseihin sekä ehdotuksia toimijuuden huomioimiseksi läpi prosessin. Osajulkaisut Kaveri, A., Silvola, A., & Muukkonen, H. (2023). Supporting student agency with a student-facing learning analytics dashboard: Perceptions of an interdisciplinary development team. Journal of Learning Analytics, 10(2), 85–99. https://doi.org/10.18608/jla.2023.7729 https://doi.org/10.18608/jla.2023.7729 Rinnakkaistallennettu versio Kaveri, A., Celik, I., Gedrimiene, E., Silvola, A., & Muukkonen, H. (2026). Longitudinal effects of learning analytics support for study planning and monitoring: Role of self-efficacy and data literacy. Computers & Education, 246, 105532. https://doi.org/10.1016/j.compedu.2025.105532 https://doi.org/10.1016/j.compedu.2025.105532 Rinnakkaistallennettu versio Kaveri, A., Korpi, J., Silvola, A., & Muukkonen, H. (in press). Staff perspectives on key dimensions of institutional learning analytics implementation. Education and Information Technologies. https://doi.org/10.1007/s10639-025-13790-4 https://doi.org/10.1007/s10639-025-13790-4 Rinnakkaistallennettu versio Academic dissertation to be presented with the assent of the Doctoral Programme Committee of Human Sciences of the University of Oulu for public defence in the Oulun Puhelin auditorium (L5), Linnanmaa, on 13 March 2026, at 12 noonAbstract
Learning analytics (LA) has shown considerable potential to support higher education (HE) students’ agency, which is defined as individuals’ proactive, self-initiated thoughts and actions that guide their learning. However, research has primarily focused on short-term or course-level applications, and evidence remains limited on how student agency manifests in the broader academic path context when supported by LA.
While LA can provide valuable support once in use, its life cycle—from development to adoption into everyday practice—is rarely straightforward. Instead, HE institutions are complex environments composed of diverse agents with varying perspectives, making LA implementation a multilayered process shaped by multiple perspectives and priorities.
To address these complexities, this article-based dissertation adopts a multistakeholder viewpoint, drawing on the experiences and views of multiple groups. It examines three interrelated levels: LA user experiences (micro), stakeholder perceptions and practices (mezzo), and institutional conditions (macro). The social cognitive perspective on agency forms the primary theoretical foundation, while complexity leadership and transformative agency approaches are employed complementarily to address mezzo- and macro-level dynamics.
A case institution implementing an LA dashboard for students and staff was investigated using a mixed-method approach (N = 127). The first study explored LA developers’ perceptions of how LA can support students; the second examined students’ perceptions of agency support provided by the dashboard over an academic year; and the third focused on staff perspectives regarding institutional enablers and barriers to implementation.
The findings indicate that LA supported student agency primarily by enhancing self-regulatory activities and decision-making. In the development context, student agency was defined as meaningful involvement and participation in decision-making. Across stakeholder and institutional levels, active participation, clear accountabilities, and the identification of actionable insights were critical for successful implementation. The findings extend our theoretical understanding through discussing agency in the LA context. In practice, the results inform institutional LA implementation and offer guidance for fostering stakeholder agency throughout the process.Tiivistelmä
Oppimisanalytiikka mahdollistaa korkeakouluopiskelijoiden toimijuuden tukemisen esimerkiksi tarjoamalla tietoa itsereflektioon, opintojen seurantaan ja suunnitteluun. Tukea toimijuudelle on kuitenkin keskitytty tarjoamaan pääosin oppimistapahtuma- ja kurssitasoilla. Tietoa on rajallisesti siitä, miten oppimisanalytiikalla tuettu opiskelijatoimijuus muotoutuu opintopolkujen tasolla.
Vaikka käytettäessä oppimisanalytiikka voi tarjota opiskelijoille arvokasta tukea, sen elinkaari suunnittelusta käyttöönottoon ei ole suoraviivainen. Korkeakoulut ovat monimutkaisia ympäristöjä, joissa operoivat moninaiset toimijat. Täten myös oppimisanalytiikan käyttöönotto on monitasoinen prosessi, jota muokkaavat eri näkökulmat ja prioriteetit.
Näiden moninaisten näkökulmien ymmärtämiseksi, tässä artikkelipohjaisessa väitöskirjassa hyödynnettiin moninäkökulmaista lähestymistapaa. Tutkimuksessa tarkasteltiin tapauskorkeakoulua, jossa käyttöönotettiin opiskelijoille ja henkilökunnalle suunnattua oppimisanalytiikan työkalua. Eri sidosryhmien (N = 127) näkökulmia tutkittiin monimenetelmäisesti. Ensimmäinen osajulkaisu tarkasteli kehittäjien näkökulmia opiskelijatoimijuuden tukemisesta oppimisanalytiikalla. Toinen osajulkaisu tutki lukuvuoden ajan opiskelijoiden näkökulmia siitä, tukeeko oppimisanalytiikka heidän toimijuuttaan. Kolmannessa osajulkaisussa keskityttiin korkeakoulun henkilökunnan näkökulmiin työkalun käyttöönotosta instituutiotasolla.
Opiskelijoiden osalta todettiin, että oppimisanalytiikka tuki toimijuutta lisäämällä mahdollisuuksia itsesäätelyyn opinnoissa ja tukemalla päätöksentekoa. Oppimisanalytiikan kehitystyössä opiskelijatoimijuus määriteltiin osallistumisena esimerkiksi päätöksentekoon. Henkilökunnan ja instituutiotason kannalta keskeisiksi nousivat sidosryhmien mukaanotto käyttöönottoprosesseihin sekä sen selkeyttäminen, mitä vastuita ja rooleja eri ryhmillä prosessissa on, ja mitä toiminnallista tietoa työkalu tarjoaa.
Tulokset laajentavat teoreettista ymmärrystämme toimijuudesta esittelemällä oppimisanalytiikan kontekstin. Käytännön tasolle tutkimustulokset tarjoavat tietoa oppimisanalytiikan käyttöönottoprosesseihin sekä ehdotuksia toimijuuden huomioimiseksi läpi prosessin
Akkupohjaisen energian varastointijärjestelmän optimaalinen mitoitus tuulivoimalalle : tapaustutkimus
No full text
Persulfate-derived porous wollastonite granules for accelerated CO2 mineralization and suitability for aggregate applications
No full textAbstract
Mineral carbonation technology is a promising solution for CO2 capture and utilization. To achieve large scale application of the technology, the challenges related to CO2 diffusion and passivation by carbonate precipitation must be overcome. In this work, we demonstrate a route to high volume CO2 capture by granulation and carbonation using wollastonite, polyvinyl alcohol (pva) and potassium persulfate. The wollastonite powder was granulated with 10% pva solution, incorporating 10–100 wt% of granulation fluid of potassium persulfate as pore–forming agent. The utility of some granules was extended by esterification reaction in citric acid solution. The granules were carbonated in a pressured reactor (10 bar, 100 °C) and the influence of pore–forming amount on carbonate passivation and CO2 diffusion was studied by thermogravimetry, optical, electron microscopy and N2 adsorption. The experiments revealed that 20% persulfate produced highly porous granules with an interconnected pore structure that reduced carbonate passivation and captured the highest amount of CO2 (44mol%). Comparatively, mix designs with 0, 10 and 100 wt% persulfate showed low carbonation due to poor CO2 diffusion attributed to surface passivation by carbonates and sulfates. Additionally, pore structure and surface modelling using Frankel–Halsey–Hill (FHH) fractal analysis concludes that 20% persulfate in both fresh and esterified granules produced a less tortuous and uniform pore structure with high interconnectivity, aiding CO2 diffusion within the granules which resulted in high amount of carbonation products while preventing passivation. After carbonation, the aggregates maintained high strength and light weight, confirming their high potential as a high-volume CO2 negative artificial lightweight aggregate in construction.Abstract
Mineral carbonation technology is a promising solution for CO2 capture and utilization. To achieve large scale application of the technology, the challenges related to CO2 diffusion and passivation by carbonate precipitation must be overcome. In this work, we demonstrate a route to high volume CO2 capture by granulation and carbonation using wollastonite, polyvinyl alcohol (pva) and potassium persulfate. The wollastonite powder was granulated with 10% pva solution, incorporating 10–100 wt% of granulation fluid of potassium persulfate as pore–forming agent. The utility of some granules was extended by esterification reaction in citric acid solution. The granules were carbonated in a pressured reactor (10 bar, 100 °C) and the influence of pore–forming amount on carbonate passivation and CO2 diffusion was studied by thermogravimetry, optical, electron microscopy and N2 adsorption. The experiments revealed that 20% persulfate produced highly porous granules with an interconnected pore structure that reduced carbonate passivation and captured the highest amount of CO2 (44mol%). Comparatively, mix designs with 0, 10 and 100 wt% persulfate showed low carbonation due to poor CO2 diffusion attributed to surface passivation by carbonates and sulfates. Additionally, pore structure and surface modelling using Frankel–Halsey–Hill (FHH) fractal analysis concludes that 20% persulfate in both fresh and esterified granules produced a less tortuous and uniform pore structure with high interconnectivity, aiding CO2 diffusion within the granules which resulted in high amount of carbonation products while preventing passivation. After carbonation, the aggregates maintained high strength and light weight, confirming their high potential as a high-volume CO2 negative artificial lightweight aggregate in construction