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Drying kinetics and energy efficiency of Y2O3–CeO2 co-doped ZrO2 powder under microwave heating
No full textAbstract
Zirconia has important application prospects in the field of ceramics. However, during a high-temperature heating process, pure zirconia will undergo martensite transformation, which seriously affects its service performance. Metal oxides, such as Y2O3–CeO2 doping ZrO2, effectively improve the toughness and fire resistance of the material. Thus, the drying of Y2O3–CeO2 co-doped ZrO2 powder is an essential step before practical application. The study employs contemporary microwave drying techniques. The results of the experiment show that the average microwave drying rate increases with an increase in mass, water content, and microwave heating power. When the initial mass was 30 g, the initial moisture content was 12 %, microwave power was 720 W, and the drying rate was the fastest. We used four dynamic models: Modified Page, Quadratic, Wang and Singh, and Page to fit the experiment data. The best model was Modified Page, which describes the kinetic process most accurately. Fick's second law describes how, in the drying process, when microwave power is 720 W, initial mass is 15 g and initial water content is 8 %, the effective diffusion coefficient is 5.25 × 10−16 m2/s. Fourier Transforms of the infrared spectrum of the samples before and after drying were analyzed, the intensity of the O–H absorption peak located at 3442.03 cm/s, and O–H–O absorption peak located at 1594.48 cm/s. Both decreased significantly after drying. To discuss the relationship between the microwave power and the diffusion coefficient, the activating energy of microwave heating was 32.01 W/g. The experimental results show high heating efficiency and selective heating of the microwave method. This study provides a theoretical basis and research data for microwave drying of Y2O3/CeO2 co-doped ZrO2 powder in industry.Abstract
Zirconia has important application prospects in the field of ceramics. However, during a high-temperature heating process, pure zirconia will undergo martensite transformation, which seriously affects its service performance. Metal oxides, such as Y2O3–CeO2 doping ZrO2, effectively improve the toughness and fire resistance of the material. Thus, the drying of Y2O3–CeO2 co-doped ZrO2 powder is an essential step before practical application. The study employs contemporary microwave drying techniques. The results of the experiment show that the average microwave drying rate increases with an increase in mass, water content, and microwave heating power. When the initial mass was 30 g, the initial moisture content was 12 %, microwave power was 720 W, and the drying rate was the fastest. We used four dynamic models: Modified Page, Quadratic, Wang and Singh, and Page to fit the experiment data. The best model was Modified Page, which describes the kinetic process most accurately. Fick's second law describes how, in the drying process, when microwave power is 720 W, initial mass is 15 g and initial water content is 8 %, the effective diffusion coefficient is 5.25 × 10−16 m2/s. Fourier Transforms of the infrared spectrum of the samples before and after drying were analyzed, the intensity of the O–H absorption peak located at 3442.03 cm/s, and O–H–O absorption peak located at 1594.48 cm/s. Both decreased significantly after drying. To discuss the relationship between the microwave power and the diffusion coefficient, the activating energy of microwave heating was 32.01 W/g. The experimental results show high heating efficiency and selective heating of the microwave method. This study provides a theoretical basis and research data for microwave drying of Y2O3/CeO2 co-doped ZrO2 powder in industry
Digital twin technology for road pavement
No full textAbstract
In recent years, the concept of Digital Twins (DT) has emerged as a promising solution for real-time monitoring and proactive maintenance of complex engineering systems. This systematic review paper provides a comprehensive overview of the current state-of-the-art in DT technology for road pavement. The paper aims to bridge the gap between the theoretical physic-based model and DT and its practical implementation in road pavement. Through a rigorous review of the literature, this study identifies the key components, challenges, and opportunities associated with the utilization of DT for road pavement. The results show that road pavement DT research is still scarce and that only a few use cases in pavement reactive maintenance have attracted the attention of the scientific community. By synthesizing the findings of this study, the paper offers insights into the prospects of DT in revolutionizing pavement proactive maintenance practices and enabling more efficient and sustainable road infrastructure.Abstract
In recent years, the concept of Digital Twins (DT) has emerged as a promising solution for real-time monitoring and proactive maintenance of complex engineering systems. This systematic review paper provides a comprehensive overview of the current state-of-the-art in DT technology for road pavement. The paper aims to bridge the gap between the theoretical physic-based model and DT and its practical implementation in road pavement. Through a rigorous review of the literature, this study identifies the key components, challenges, and opportunities associated with the utilization of DT for road pavement. The results show that road pavement DT research is still scarce and that only a few use cases in pavement reactive maintenance have attracted the attention of the scientific community. By synthesizing the findings of this study, the paper offers insights into the prospects of DT in revolutionizing pavement proactive maintenance practices and enabling more efficient and sustainable road infrastructure
When the tropics came North: how exotic fruits conquered Finnish plates in the times of empires
No full textAbstract
This chapter gives a long-term overview of the process by which the global spread of tropical fruits became integrated into the diet of people living in Finland. Newspapers serve as primary sources, and on the basis of cookbooks, it is possible to study when tropical fruits stopped being a luxury and became a vitamin-rich necessity. The establishment of banana plantations in Jamaica was reflected in their supply in Finland during the early twentieth century, when the first advertisements for fresh bananas appeared in newspapers. Major changes in the environment of banana production areas were reported but, above all, the newspapers concentrated on the healthiness of bananas and their significance as ‘the best nutrient in the world’. Finland never had control over any overseas territories, but it had colonial shops. Since the 1920s, people in Finland tried to get rid of the memory of belonging to the Russian Empire (also in food-related names and products), but at the same time they benefited from the colonies of Western European empires and the large fruit companies. The main question of this chapter is: What was the role of a small northern country among the European countries in the time of Empires?Abstract
This chapter gives a long-term overview of the process by which the global spread of tropical fruits became integrated into the diet of people living in Finland. Newspapers serve as primary sources, and on the basis of cookbooks, it is possible to study when tropical fruits stopped being a luxury and became a vitamin-rich necessity. The establishment of banana plantations in Jamaica was reflected in their supply in Finland during the early twentieth century, when the first advertisements for fresh bananas appeared in newspapers. Major changes in the environment of banana production areas were reported but, above all, the newspapers concentrated on the healthiness of bananas and their significance as ‘the best nutrient in the world’. Finland never had control over any overseas territories, but it had colonial shops. Since the 1920s, people in Finland tried to get rid of the memory of belonging to the Russian Empire (also in food-related names and products), but at the same time they benefited from the colonies of Western European empires and the large fruit companies. The main question of this chapter is: What was the role of a small northern country among the European countries in the time of Empires
Dyspnoea and chest pain as prodromal symptoms prior to sudden cardiac death
No full textTausta: Kuolemista jopa 10-20% on äkillisiä sydänpysähdyksiä (sydänperäinen äkkikuolema). Sen ilmaantuvuus kasvaa progressiivisesti iän myötä nousten jo 35-ikävuoden jälkeen. Taustatekijänä on usein sepelvaltimotauti, jonka ensioire voi olla äkkikuolema. Osa uhreista on kuitenkin voinut kokea mahdollisia ennakko-oireita, joihin reagoiminen voi tarjota lyhyen aikaikkunan puuttua interventioin tapahtumien kulkuun.
Tutkimusongelma: Tavoitteena oli selvittää rintakivun ja hengenahdistuksen esiintyvyyttä ennen sydänperäistä äkkikuolemaa, sillä aiemmin em. oireet on yhdistetty sydänperäisen äkkikuoleman riskiin. Keillä oireita esiintyy yleisimmin sekä miten niihin reagoidaan ja eroavatko oireelliset oireettomista lopullisen kuolinsyyn perusteella toisistaan.
Aineisto ja tutkimusmenetelmät: Lähdeaineistona on kohorttityyppinen retrospektiivinen aineisto Fingesture (Finnish Genetic Study of Arrhythmic Events), joka sisältää oikeuslääketieteellisen ruumiinavauksen läpikäyneet vainajat, joiden kuolinsyyksi on varmistunut sydänperäinen kuolinsyy. Tieto oireilusta ennen kuolemaa on kerätty avauspöytäkirjasta ja sisältää vainajat Pohjois-Suomen alueelta vuosilta 2018-2022.
Tulokset: Mahdollisia ennakoivia oireita oli kokenut 17,0% uhreista. Mediaani-ikä oli 69 vuotta ja miehet kuolivat 5,5 vuotta nuorempina. Hengenahdistusta koki erityisesti edeltävästi sydänsairaat. Oireilu siirtää elottomuuksia tapahtumaan enemmän terveydenhuollossa ja maallikoiden todistamaksi. Siltikin suurin osa oireilevista (73%) kuoli terveydenhuollon yksikön ulkopuolella. Iskeeminen kuolinsyy oli yleisin kuolinsyy, johon edeltävä rintakipuoire voi viitata.
Johtopäätös: Sydänpysähdystä edeltäviä oireita on mahdollisesti kokenut lähes viidennes, joista suurin osa on löydetty kuolleena ja vain osa elottomuuksista on siirtynyt tapahtumaan terveydenhuollossa. Maallikoiden tietoisuus riskioireista ja sydänsairauksien aikaisesta diagnosoinnista voi ennaltaehkäistä sydänperäisiä äkkikuolemia
Cultural heritage, sustainability, and community-based tourism: A best practice case study
No full textAbstract
This chapter opens with a discussion on international policy discussions around the importance of community inclusion in order to promote sustainable development. before shifting into the barriers to this inclusion within local planning systems as well as the difficulty in implementing inclusive processes within complex power systems. This is followed by a more focused discussion of cultural heritage and community-based tourism development, noting the importance of capacity-building for the local community and highlighting the risks of an overemphasis on tourism growth over community development. Finally, the chapter presents a best practice case study, Nizamuddin Urban Renewal Initiative in Delhi, India. This case study illustrates the application of many of the key factors to successful and sustainable cultural community-based tourism development.Abstract
This chapter opens with a discussion on international policy discussions around the importance of community inclusion in order to promote sustainable development. before shifting into the barriers to this inclusion within local planning systems as well as the difficulty in implementing inclusive processes within complex power systems. This is followed by a more focused discussion of cultural heritage and community-based tourism development, noting the importance of capacity-building for the local community and highlighting the risks of an overemphasis on tourism growth over community development. Finally, the chapter presents a best practice case study, Nizamuddin Urban Renewal Initiative in Delhi, India. This case study illustrates the application of many of the key factors to successful and sustainable cultural community-based tourism development
The status of multilingual students in school : forms of structural discrimination and teachers’ opportunities to support equality
No full textTämän kandidaatintutkielman aiheena on monikielisyys ja monikieliset oppilaat. Tutkielman tarkoituksena on tarkastella, miten suomalaisen koulutusjärjestelmän rakenteet syrjivät monikielisiä oppilaita, sekä sitä, miten opettajat voivat tukea omalla toiminnallaan monikielisten oppilaiden yhdenvertaisuutta opetuksessa. Tutkielmassa tarkastelemme tarkemmin koulun rakenteita, kuten kielipolitiikkaa, opetussuunnitelmaa, lainsäädäntöä, resursseja, tukitoimia ja menetelmiä. Opettajan näkökulmasta tarkastelemme opettajien asenteita ja pedagogisia valintoja, kuten opetusmenetelmiä ja oppimateriaaleja. Tutkielma on toteutettu kuvailevana kirjallisuuskatsauksena, sillä tarkoituksena on muodostaa laaja kokonaiskuva aiheestamme. Aineistona on käytetty suomalaisia sekä kansainvälisiä vertaisarvioituja lähteitä, kuten tutkimusartikkeleita ja väitöskirjoja.
Tutkielman aiheen ajankohtaisuutta voidaan perustella monikielisyyden lisääntymisellä. Suomalainen koulutusjärjestelmä muuttuu koko ajan yhä moninaisemmaksi ja monikielisemmäksi. Myös nykyinen opetussuunnitelma painottaa kielitietoisuutta ja monikielisyys nähdään oppilaiden voimavarana. Lisäksi aihe on myös yhteiskunnallisesti merkittävä, sillä yhdenvertaisuus on yksi perusoikeuksista.
Tutkielman tulokset osoittavat, että vaikka koulun rakenteet, kuten opetussuunnitelma, lainsäädäntö ja opetuksen järjestäminen tunnistavat monikielisyyden, ei tavoite toteudu aina luokkahuonetasolla. Opetussuunnitelma määrittelee monikielisyyden osaksi koulun toimintakulttuuria, mutta jättää ulkopuolelle käytännön ohjeet ja keinot monikielisyyden tukemiseen.
Tutkimuksen tulokset osoittavat, että opettajien asenteet ja koulujen kielipolitiikka on muuttunut positiivisempaan suuntaan, mutta suomalainen koulutusjärjestelmä perustuu edelleen osittain yksikielisyyden normiin. Myös esimerkiksi oppimateriaalit lisäävät yksikielisyysajattelua. Opettajien asenteilla on merkittävä vaikutus monikielisyyden toteutumisessa luokkahuoneessa, mutta koska koulun rakenteet antavat opettajalle mahdollisuuden ja vapauden toteuttaa opetusta ja kielipolitiikkaa parhaalla katsomallaan tavalla, on luokka- ja aluekohtaisia eroja monikielisyyden toteutumisesta paljon. Vaikka yksikielisyyden normia kouluissa on pyritty murtamaan, eivät kielitietoiset menetelmät tai myönteinen asenne saavuta tasavertaisesti kaikkia kouluja ja niiden monikielisiä oppilaita
Towards a Collaborative Approach and Structure for Engaged Research
No full textAbstract
The evolving relationship between research and its impact on communities has sparked ongoing discussions. Traditional research methods are criticized for having limited societal influence due to their restricted accessibility. Engaged research emerges as a transformative methodology, emphasizing collaboration with communities in research design and knowledge production. This paper advocates for the integration of engaged research into higher education curricula to foster civic and social responsibility. This paper explores four cases of integrating engaged research into teaching, drawing on examples from University College Cork in Ireland, Koç University in Türkiye, and the University of Oulu in Finland. At University College Cork, a three-part approach combines lecturer presentations and class discussions, interactive class activities, and student led engaged research projects. Koç University’s Social Impact Forum in Türkiye emphasizes social impact through engaged research initiatives. In Finland, the University of Oulu incorporates research-based pilot projects in land-use planning, alongside a research and development course that empowers children to take an active role in the learning process. The authors argue that such integration enhances the impact of research, nurturing engaged citizens for transformative initiatives.Abstract
The evolving relationship between research and its impact on communities has sparked ongoing discussions. Traditional research methods are criticized for having limited societal influence due to their restricted accessibility. Engaged research emerges as a transformative methodology, emphasizing collaboration with communities in research design and knowledge production. This paper advocates for the integration of engaged research into higher education curricula to foster civic and social responsibility. This paper explores four cases of integrating engaged research into teaching, drawing on examples from University College Cork in Ireland, Koç University in Türkiye, and the University of Oulu in Finland. At University College Cork, a three-part approach combines lecturer presentations and class discussions, interactive class activities, and student led engaged research projects. Koç University’s Social Impact Forum in Türkiye emphasizes social impact through engaged research initiatives. In Finland, the University of Oulu incorporates research-based pilot projects in land-use planning, alongside a research and development course that empowers children to take an active role in the learning process. The authors argue that such integration enhances the impact of research, nurturing engaged citizens for transformative initiatives
The use and perceived benefits of digital health services among Finnish older adults: Survey study
No full textAbstract
Background:
The rapid expansion of digital health services (DHS) highlights the need to assess their accessibility and effectiveness, particularly among older adults. Despite increasing digitalization, many older individuals still face barriers, including limitations in digital competence and access.
Objective:
This study examines the use, barriers, and perceived benefits of DHS among individuals aged 75 and older in Finland.
Methods:
A nationwide survey was conducted in March 2023 using both electronic and paper questionnaires. In addition to descriptive analysis, regression analysis was performed to identify variables associated with perceived benefits of digital health services.
Results:
Of the 1124 responses (1011 electronic, 113 paper), 1100 were fully completed. Overall, 84% of respondents had used DHS, with usage being higher among those under 85 years (87%) than those over 85 (57%). The majority of respondents (82%) reported using the national Omakanta service, which grants access to personal health information. Digital competence and the number of services used were the strongest predictors of perceived benefits, alongside higher satisfaction, service frequency, and female gender.
Conclusions:
DHS adoption among older adults, especially in Finland, may be higher than previously reported. However, digital social services remain underdeveloped. Addressing the digital divide is essential to ensuring equitable access.Abstract
Background:
The rapid expansion of digital health services (DHS) highlights the need to assess their accessibility and effectiveness, particularly among older adults. Despite increasing digitalization, many older individuals still face barriers, including limitations in digital competence and access.
Objective:
This study examines the use, barriers, and perceived benefits of DHS among individuals aged 75 and older in Finland.
Methods:
A nationwide survey was conducted in March 2023 using both electronic and paper questionnaires. In addition to descriptive analysis, regression analysis was performed to identify variables associated with perceived benefits of digital health services.
Results:
Of the 1124 responses (1011 electronic, 113 paper), 1100 were fully completed. Overall, 84% of respondents had used DHS, with usage being higher among those under 85 years (87%) than those over 85 (57%). The majority of respondents (82%) reported using the national Omakanta service, which grants access to personal health information. Digital competence and the number of services used were the strongest predictors of perceived benefits, alongside higher satisfaction, service frequency, and female gender.
Conclusions:
DHS adoption among older adults, especially in Finland, may be higher than previously reported. However, digital social services remain underdeveloped. Addressing the digital divide is essential to ensuring equitable access
Associations of dental anxiety, depression, and general anxiety: A structural equation modeling study in the Northern Finland Birth Cohort 1986
No full textAbstract
We aimed to estimate the associations between anticipatory and treatment-related dental anxiety and depression and general anxiety at the latent level. This cross-sectional study analyzed data from 3320 adults aged 33–35 years in the Northern Finland Birth Cohort 1986. Dental anxiety was measured with the Modified Dental Anxiety Scale and general anxiety and depression with the Hopkins Symptom Checklist-25. Confirmatory factor analyses supported a two-factor model with a residual correlation for dental anxiety (comparative fit index [CFI] = 0.999, root mean square error of approximation [RMSEA] = 0.038). Structural equation modeling was used to estimate primary latent correlations between anticipatory dental anxiety, treatment-related dental anxiety, depression, and general anxiety. Secondary models adjusted for sex, education, and smoking. Depression and general anxiety correlated strongly (r = 0.72). Both anticipatory and treatment-related dental anxiety showed modest associations with general anxiety (r = 0.16–0.18), whereas associations with depression were weaker and attenuated after adjustment. The two dental anxiety constructs were strongly interrelated (r = 0.85). Female sex, lower education, and smoking predicted higher dental anxiety. These findings support the distinctiveness of the two constructs of dental anxiety from depression and general anxiety, though partly overlapping with the latter. Future research should further clarify their developmental pathways and shared mechanisms.Abstract
We aimed to estimate the associations between anticipatory and treatment-related dental anxiety and depression and general anxiety at the latent level. This cross-sectional study analyzed data from 3320 adults aged 33–35 years in the Northern Finland Birth Cohort 1986. Dental anxiety was measured with the Modified Dental Anxiety Scale and general anxiety and depression with the Hopkins Symptom Checklist-25. Confirmatory factor analyses supported a two-factor model with a residual correlation for dental anxiety (comparative fit index [CFI] = 0.999, root mean square error of approximation [RMSEA] = 0.038). Structural equation modeling was used to estimate primary latent correlations between anticipatory dental anxiety, treatment-related dental anxiety, depression, and general anxiety. Secondary models adjusted for sex, education, and smoking. Depression and general anxiety correlated strongly (r = 0.72). Both anticipatory and treatment-related dental anxiety showed modest associations with general anxiety (r = 0.16–0.18), whereas associations with depression were weaker and attenuated after adjustment. The two dental anxiety constructs were strongly interrelated (r = 0.85). Female sex, lower education, and smoking predicted higher dental anxiety. These findings support the distinctiveness of the two constructs of dental anxiety from depression and general anxiety, though partly overlapping with the latter. Future research should further clarify their developmental pathways and shared mechanisms