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The effect of ageing, oestrogen and diet hardness on rat mandibular condylar cartilage
No full textAbstract
The aim of this study was to examine the effects of ageing, oestrogen, and dietary loading on the structure and composition of the mandibular condylar cartilage (MCC) in rats. The study was done using histomorphometry, immunohistochemistry, Fourier-transform infrared (FTIR) spectroscopy, and polarised light microscopy (PLM).
Morphometric characteristics and collagen expressions were studied in the MCC of 75 male and female rats exposed to different dietary loading conditions. The results showed that a hard diet increased cartilage thickness and type I collagen expression, especially in younger rats, while ageing was associated with increased Type II collagen expression.
Collagen and proteoglycan composition were analysed in 96 female rats using FTIR spectroscopy. Oestrogen deficiency was induced by ovariectomy at 7 weeks of age. Ageing and a soft diet were associated with increased collagen content in deeper layers of the MCC, while a hard diet enhanced proteoglycan content. Oestrogen deficiency modified the distribution of both collagen and proteoglycan.
Collagen fibre orientation and retardance in PLM were studied in the same ovariectomised and non-ovariectomised female rat groups as in the FTIR spectroscopy study. Ageing led to increased fibre disorientation and reduced retardance. Oestrogen deficiency further impaired collagen alignment, whereas diet board feeding increased the orientation angle in the deep layer.
The results of this study suggest that ageing, low oestrogen levels, and reduced masticatory loading compromise the structural integrity of the MCC in the regions analysed, increasing their susceptibility to region-specific alterations in cartilage composition and organisation. Original papers Orajärvi, M., Laaksonen, S., Hauru, R., Mursu, E., Jonaviciute, E., Voipio, H.-M., Raustia, A., & Pirttiniemi, P. (2018). Changes in type I and type II collagen expression in rat mandibular condylar cartilage associated with aging and dietary loading. Journal of Oral & Facial Pain and Headache, 32(3), 258–265. https://doi.org/10.11607/ofph.1581 https://doi.org/10.11607/ofph.1581 Hauru, R., Rieppo, L., Tuomisto, T., Yu, J., Laaksonen, S., Saarakkala, S., Raustia, A., & Pirttiniemi, P. (2024). Fourier‐transform infrared study on effects of ageing, oestrogen level and altered dietary loading on rat mandibular condylar cartilage. Orthodontics & Craniofacial Research, 27(1), 151–164. https://doi.org/10.1111/ocr.12693 https://doi.org/10.1111/ocr.12693 Self-archived version Hauru, R., Shakya, B., Rieppo, L., Silvola, A., Yu, J., Laaksonen, S., Saarakkala, S., Raustia, A., & Pirttiniemi, P. (2025). Effects of ageing, oestrogen level and altered dietary loading on rat mandibular cartilage—A polarised light microscopy study. Orthodontics & Craniofacial Research, 28(6), 971–976. https://doi.org/10.1111/ocr.70010 https://doi.org/10.1111/ocr.70010 Self-archived version Tiivistelmä
Tutkimuksen tavoitteena oli selvittää iän, estrogeenitason ja purentarasituksen vaikutuksia rotan alaleuan kondyyliruston rakenteeseen ja koostumukseen. Tutkimuksen menetelminä käytettiin histomorfometriaa, immunohistokemiaa, Fourier-muunnettua infrapunaspektroskopiaa (FTIR) ja polarisoivaa valomikroskopiaa (PLM). Kondyyliruston eri kerrosten paksuutta ja kollageenia tutkittiin 75 naaras- ja urospuolisella rotalla, jotka altistettiin erilaisille ruokavalion aiheuttamille purentakuormituksille. Tulokset osoittivat lisääntyneen purentakuormituksen lisäävän ruston paksuutta ja tyypin I kollageenin määrää erityisesti nuorilla rotilla, kun taas ikääntyminen lisäsi tyypin II kollageenin määrää. FTIR-spektroskopiaa käytettiin analysoimaan tyypin I ja II kollageenin sekä proteoglykaanien ilmentymistä 96 naarasrotan kondyylirustossa. Näistä osalle oli tehty ovariektomia estrogeenitasoerojen aikaansaamiseksi. Ikääntyminen ja pehmeä ruokavalio lisäsivät kollageenin määrää syvissä rustosolukerroksissa, kun taas kova ruokavalio lisäsi proteoglykaanipitoisuutta. Estrogeenivaje vaikutti sekä kollageenin että proteoglykaanien jakautumiseen rustossa.
Kollageenisäikeiden suuntautumista ja viivettä (retardanssia) PLM-menetelmää käytettäessä tutkittiin samoilla alaleuan kondyylirustonäytteillä kuin FTIR-analyysissä. Ikääntyminen lisäsi kollageenisäikeiden epäjärjestystä ja vähensi retardanssia erityisesti ruston pintakerroksessa. Estrogeenivaje ja pehmeä ruokavalio heikensivät kollageenisäikeiden järjestäytyneisyyttä, kun taas kova ruokavalio näyttäisi lieventävän näitä muutoksia.
Tulokset viittaavat, että ikä, matala estrogeenitaso ja vähentynyt kuormitus heikentävät kondyyliruston rakennetta tutkituilla alueilla voiden altistaa sen paikallisille muutoksille ruston koostumuksessa. Osajulkaisut Orajärvi, M., Laaksonen, S., Hauru, R., Mursu, E., Jonaviciute, E., Voipio, H.-M., Raustia, A., & Pirttiniemi, P. (2018). Changes in type I and type II collagen expression in rat mandibular condylar cartilage associated with aging and dietary loading. Journal of Oral & Facial Pain and Headache, 32(3), 258–265. https://doi.org/10.11607/ofph.1581 https://doi.org/10.11607/ofph.1581 Hauru, R., Rieppo, L., Tuomisto, T., Yu, J., Laaksonen, S., Saarakkala, S., Raustia, A., & Pirttiniemi, P. (2024). Fourier‐transform infrared study on effects of ageing, oestrogen level and altered dietary loading on rat mandibular condylar cartilage. Orthodontics & Craniofacial Research, 27(1), 151–164. https://doi.org/10.1111/ocr.12693 https://doi.org/10.1111/ocr.12693 Rinnakkaistallennettu versio Hauru, R., Shakya, B., Rieppo, L., Silvola, A., Yu, J., Laaksonen, S., Saarakkala, S., Raustia, A., & Pirttiniemi, P. (2025). Effects of ageing, oestrogen level and altered dietary loading on rat mandibular cartilage—A polarised light microscopy study. Orthodontics & Craniofacial Research, 28(6), 971–976. https://doi.org/10.1111/ocr.70010 https://doi.org/10.1111/ocr.70010 Rinnakkaistallennettu versio Academic dissertation to be presented with the assent of the Doctoral Programme Committee of Health and Biosciences of the University of Oulu for public defence in the Leena Palotie auditorium (101A) of the Faculty of Medicine (Aapistie 5 A), on 20 March 2026, at 12 noonAbstract
The aim of this study was to examine the effects of ageing, oestrogen, and dietary loading on the structure and composition of the mandibular condylar cartilage (MCC) in rats. The study was done using histomorphometry, immunohistochemistry, Fourier-transform infrared (FTIR) spectroscopy, and polarised light microscopy (PLM).
Morphometric characteristics and collagen expressions were studied in the MCC of 75 male and female rats exposed to different dietary loading conditions. The results showed that a hard diet increased cartilage thickness and type I collagen expression, especially in younger rats, while ageing was associated with increased Type II collagen expression.
Collagen and proteoglycan composition were analysed in 96 female rats using FTIR spectroscopy. Oestrogen deficiency was induced by ovariectomy at 7 weeks of age. Ageing and a soft diet were associated with increased collagen content in deeper layers of the MCC, while a hard diet enhanced proteoglycan content. Oestrogen deficiency modified the distribution of both collagen and proteoglycan.
Collagen fibre orientation and retardance in PLM were studied in the same ovariectomised and non-ovariectomised female rat groups as in the FTIR spectroscopy study. Ageing led to increased fibre disorientation and reduced retardance. Oestrogen deficiency further impaired collagen alignment, whereas diet board feeding increased the orientation angle in the deep layer.
The results of this study suggest that ageing, low oestrogen levels, and reduced masticatory loading compromise the structural integrity of the MCC in the regions analysed, increasing their susceptibility to region-specific alterations in cartilage composition and organisation.Tiivistelmä
Tutkimuksen tavoitteena oli selvittää iän, estrogeenitason ja purentarasituksen vaikutuksia rotan alaleuan kondyyliruston rakenteeseen ja koostumukseen. Tutkimuksen menetelminä käytettiin histomorfometriaa, immunohistokemiaa, Fourier-muunnettua infrapunaspektroskopiaa (FTIR) ja polarisoivaa valomikroskopiaa (PLM). Kondyyliruston eri kerrosten paksuutta ja kollageenia tutkittiin 75 naaras- ja urospuolisella rotalla, jotka altistettiin erilaisille ruokavalion aiheuttamille purentakuormituksille. Tulokset osoittivat lisääntyneen purentakuormituksen lisäävän ruston paksuutta ja tyypin I kollageenin määrää erityisesti nuorilla rotilla, kun taas ikääntyminen lisäsi tyypin II kollageenin määrää. FTIR-spektroskopiaa käytettiin analysoimaan tyypin I ja II kollageenin sekä proteoglykaanien ilmentymistä 96 naarasrotan kondyylirustossa. Näistä osalle oli tehty ovariektomia estrogeenitasoerojen aikaansaamiseksi. Ikääntyminen ja pehmeä ruokavalio lisäsivät kollageenin määrää syvissä rustosolukerroksissa, kun taas kova ruokavalio lisäsi proteoglykaanipitoisuutta. Estrogeenivaje vaikutti sekä kollageenin että proteoglykaanien jakautumiseen rustossa.
Kollageenisäikeiden suuntautumista ja viivettä (retardanssia) PLM-menetelmää käytettäessä tutkittiin samoilla alaleuan kondyylirustonäytteillä kuin FTIR-analyysissä. Ikääntyminen lisäsi kollageenisäikeiden epäjärjestystä ja vähensi retardanssia erityisesti ruston pintakerroksessa. Estrogeenivaje ja pehmeä ruokavalio heikensivät kollageenisäikeiden järjestäytyneisyyttä, kun taas kova ruokavalio näyttäisi lieventävän näitä muutoksia.
Tulokset viittaavat, että ikä, matala estrogeenitaso ja vähentynyt kuormitus heikentävät kondyyliruston rakennetta tutkituilla alueilla voiden altistaa sen paikallisille muutoksille ruston koostumuksessa
Iran is falling behind WHO cervical cancer elimination targets: HPV vaccination coverage and cervical cancer screening participation in 2021
No full textAbstract
Objective:
This study aimed to assess HPV vaccination coverage and cervical cancer screening participation among Iranian females under 46 years old, comparing Iran’s situation to he Cervical Cancer Elimination Initiative (CCEI) targets.
Methods:
This nationally and sub-nationally representative cross-sectional study analyzed data from the STEPS 2021 survey. Female participants aged 18–45 years without missing data on HPV vaccination or cervical cancer screening were included. Categorical data were presented as weighted percentages with 95% confidence intervals (95% CI). Logistic regression assessed associations between demographic and female cancer screening variables with the outcomes.
Results:
A total of 8,158 females were included. Only 0.85% (95% CI: 0.69–1.02) of women received the HPV vaccine, while cervical cancer screening participation was 39.4% (95% CI: 38.21–40.6). No significant differences in HPV vaccination coverage were observed across age groups. However, screening rates were significantly higher in older women, rising from 27.99% (18–35 years) to 54.07% (36–45 years). HPV vaccination was not significantly associated with demographic variables. In contrast, cervical cancer screening participation was higher among unemployed women (40.58%), married women (49.6%), and those in the highest wealth quintile (42.47% compared to 28.29% in the lowest quintile).
Conclusion:
HPV vaccination coverage in Iran is critically low, falling far short of the CCEI target of 90%. Cervical cancer screening participation is comparatively better but still lags approximately 30% behind the target. Strategic interventions are critical to bridge the gap between Iran’s current status and the CCEI targets.Abstract
Objective:
This study aimed to assess HPV vaccination coverage and cervical cancer screening participation among Iranian females under 46 years old, comparing Iran’s situation to he Cervical Cancer Elimination Initiative (CCEI) targets.
Methods:
This nationally and sub-nationally representative cross-sectional study analyzed data from the STEPS 2021 survey. Female participants aged 18–45 years without missing data on HPV vaccination or cervical cancer screening were included. Categorical data were presented as weighted percentages with 95% confidence intervals (95% CI). Logistic regression assessed associations between demographic and female cancer screening variables with the outcomes.
Results:
A total of 8,158 females were included. Only 0.85% (95% CI: 0.69–1.02) of women received the HPV vaccine, while cervical cancer screening participation was 39.4% (95% CI: 38.21–40.6). No significant differences in HPV vaccination coverage were observed across age groups. However, screening rates were significantly higher in older women, rising from 27.99% (18–35 years) to 54.07% (36–45 years). HPV vaccination was not significantly associated with demographic variables. In contrast, cervical cancer screening participation was higher among unemployed women (40.58%), married women (49.6%), and those in the highest wealth quintile (42.47% compared to 28.29% in the lowest quintile).
Conclusion:
HPV vaccination coverage in Iran is critically low, falling far short of the CCEI target of 90%. Cervical cancer screening participation is comparatively better but still lags approximately 30% behind the target. Strategic interventions are critical to bridge the gap between Iran’s current status and the CCEI targets
Coupling metastability engineering and martensite strengthening in Si-alloyed AISI 304L stainless steel toward enhanced strength-ductility synergy
No full textAbstract
Strength enhancement through grain refinement in the AISI 304L stainless steel often leads to a notable reduction in ductility due to the suppression of the transformation-induced plasticity (TRIP) effect. Accordingly, the potential of Si addition for performance improvement of AISI 304L stainless steel through coupled metastability engineering and martensite strengthening was investigated. The 304L, 304L-Si3, and 304L-Si5 (at%) alloys with controlled stacking fault energy (SFE) were examined under different grain sizes. Tensile behavior, work-hardening response, phase transformation kinetics, and strengthening mechanisms were systematically investigated. The results revealed that Si addition effectively reduces SFE and promotes TRIP effect at fine grain sizes, resulting in superior work-hardening capability, enhanced ductility, and improved tensile toughness compared to the base 304L alloy. Notably, the 304L-Si3 alloy provided a more favorable strength-ductility balance (strength ∼1031 MPa and elongation ∼73 %), surpassing many advanced high-strength steels. Kinetic analysis demonstrated that the 304L-Si3 alloy with a fully austenitic initial structure provides optimized martensitic transformation kinetics, retaining the transformation to higher strains and thereby leading to higher uniform elongations. Furthermore, Si alloying increases the intrinsic strength of the α′-martensite phase, with estimated strength values of ∼1.56, ∼1.67, and ∼1.70 GPa for the 304L, 304L-Si3, and 304L-Si5 alloys, respectively.Abstract
Strength enhancement through grain refinement in the AISI 304L stainless steel often leads to a notable reduction in ductility due to the suppression of the transformation-induced plasticity (TRIP) effect. Accordingly, the potential of Si addition for performance improvement of AISI 304L stainless steel through coupled metastability engineering and martensite strengthening was investigated. The 304L, 304L-Si3, and 304L-Si5 (at%) alloys with controlled stacking fault energy (SFE) were examined under different grain sizes. Tensile behavior, work-hardening response, phase transformation kinetics, and strengthening mechanisms were systematically investigated. The results revealed that Si addition effectively reduces SFE and promotes TRIP effect at fine grain sizes, resulting in superior work-hardening capability, enhanced ductility, and improved tensile toughness compared to the base 304L alloy. Notably, the 304L-Si3 alloy provided a more favorable strength-ductility balance (strength ∼1031 MPa and elongation ∼73 %), surpassing many advanced high-strength steels. Kinetic analysis demonstrated that the 304L-Si3 alloy with a fully austenitic initial structure provides optimized martensitic transformation kinetics, retaining the transformation to higher strains and thereby leading to higher uniform elongations. Furthermore, Si alloying increases the intrinsic strength of the α′-martensite phase, with estimated strength values of ∼1.56, ∼1.67, and ∼1.70 GPa for the 304L, 304L-Si3, and 304L-Si5 alloys, respectively
Surface and Interface Engineered Hydrated Nickel Hydroxide on Nickel Enables Rapid Active Species Shuffling in Alkaline Hydrogen Electrocatalysis
No full textAbstract
Achieving acid-like hydrogen oxidation reaction (HOR) and hydrogen evolution reaction (HER) activity in alkaline media using low-cost, non-precious metal catalysts is essential for energy conversion technologies. Here, we demonstrate the indispensable role of water within the catalyst layer in enhancing HOR/HER kinetics, mediated by hydrated and dehydrated oxophilic sites on nickel (Ni) catalysts coated with nickel hydroxide (Ni(OH)2). Electrochemical measurements combined with density functional theory (DFT) calculations show that an acid-like environment creates at the electrified interface through water molecules that bridge active hydrogen and oxygen species within the catalyst surface layer. This interfacial behavior differs from that described in conventional bulk and interface models. Our findings highlight the importance of interfacial hydrogen bonding network across the interface in hydrogen electrocatalysis and provide guidance for the design of efficient catalysts for alkaline fuel cell and electrolyzer applications.Abstract
Achieving acid-like hydrogen oxidation reaction (HOR) and hydrogen evolution reaction (HER) activity in alkaline media using low-cost, non-precious metal catalysts is essential for energy conversion technologies. Here, we demonstrate the indispensable role of water within the catalyst layer in enhancing HOR/HER kinetics, mediated by hydrated and dehydrated oxophilic sites on nickel (Ni) catalysts coated with nickel hydroxide (Ni(OH)2). Electrochemical measurements combined with density functional theory (DFT) calculations show that an acid-like environment creates at the electrified interface through water molecules that bridge active hydrogen and oxygen species within the catalyst surface layer. This interfacial behavior differs from that described in conventional bulk and interface models. Our findings highlight the importance of interfacial hydrogen bonding network across the interface in hydrogen electrocatalysis and provide guidance for the design of efficient catalysts for alkaline fuel cell and electrolyzer applications
Building Successful Team Interaction in Online Team Coaching Process: A Case Study
No full textAbstract
In the post-COVID-19 era, work has expanded to multiple locations with teams operating increasingly online, where successful team interaction between colleagues is a more challenging task. Thus, this study explores factors in online team coaching that build successful team interaction. This study uses a qualitative case study with video observations to examine the interactions between a coach and a small to medium-sized enterprise (SME) team over a 2-month online coaching program focused on teamwork skills. Findings of this study introduce a framework of the main factors: personality, skills, and coaching. Factors related to personality included person-related factors, whereas factors related to skills included emotion-related, relationship-related, and cognition-related factors. Finally, factors related to coaching included situation-related, process-related, and information-related factors. Findings of this study also elucidate how these factors manifest during the initial, middle, and closing phases of the online team coaching. This study contributes to current academic literature on managing online team interactions with an understanding of factors building successful team interaction, particularly in online settings, which is lacking in the current literature. This study gives practical insights to team leaders on how to build successful interactive dynamics within teams to cultivate business goals through successful online team interaction. Findings of this study are also useful for developing more effective online team coaching services.Abstract
In the post-COVID-19 era, work has expanded to multiple locations with teams operating increasingly online, where successful team interaction between colleagues is a more challenging task. Thus, this study explores factors in online team coaching that build successful team interaction. This study uses a qualitative case study with video observations to examine the interactions between a coach and a small to medium-sized enterprise (SME) team over a 2-month online coaching program focused on teamwork skills. Findings of this study introduce a framework of the main factors: personality, skills, and coaching. Factors related to personality included person-related factors, whereas factors related to skills included emotion-related, relationship-related, and cognition-related factors. Finally, factors related to coaching included situation-related, process-related, and information-related factors. Findings of this study also elucidate how these factors manifest during the initial, middle, and closing phases of the online team coaching. This study contributes to current academic literature on managing online team interactions with an understanding of factors building successful team interaction, particularly in online settings, which is lacking in the current literature. This study gives practical insights to team leaders on how to build successful interactive dynamics within teams to cultivate business goals through successful online team interaction. Findings of this study are also useful for developing more effective online team coaching services
Environmental Filtering Correlates More Strongly With Taxonomic and Functional Beta Diversity of Phytoplankton Assemblages Than Spatial Structuring in a High-Altitude River–Lake System
No full textAbstract
1. Understanding overall beta diversity (βtotal) and its components—species replacement (βrepl) and richness difference (βrich)—is essential for disentangling the mechanisms that structure aquatic communities. However, it remains poorly understood how taxonomic and functional beta diversity correlate with environmental and spatial processes in high-altitude river–lake systems. This study quantified spatial and seasonal variation in phytoplankton beta diversity and identified correlations with environmental and spatial variables across the Qinghai Lake Basin, located on the northeastern Qinghai–Tibet Plateau.
2. We integrated taxonomic and functional approaches to quantify beta diversity patterns using phytoplankton assemblages collected from inflowing tributaries (IT) and the main lake (ML) during summer and autumn. Beta diversity was partitioned into replacement and richness components, and its relationships with environmental and spatial effects were examined using variation partitioning analysis and partial Mantel tests.
3. Taxonomic βtotal and βrepl were marginally higher in tributaries than in the main lake, whereas functional beta diversity and its two components were significantly higher in tributaries. Both taxonomic and functional beta diversity remained stable between seasons in the main lake but increased markedly from summer to autumn in tributaries. Taxonomic beta diversity mainly comprised species replacement (56.65%–69.17%), while functional beta diversity was dominated by richness difference (62.96%–76.19%). Environmental filtering variables, particularly salinity and water temperature, explained a greater portion of community variation than spatial variables.
4. These findings highlight that niche-based environmental filtering and dispersal limitation jointly correlated with phytoplankton beta diversity in this high-altitude river–lake system.
5. Salinity emerged as a particularly influential factor, shaping phytoplankton assemblage variation through strong physiological filtering. The present study highlights the value of integrating both taxonomic and functional perspectives to better elucidate spatio-temporal patterns of phytoplankton biodiversity in high-altitude aquatic ecosystems.Abstract
1. Understanding overall beta diversity (βtotal) and its components—species replacement (βrepl) and richness difference (βrich)—is essential for disentangling the mechanisms that structure aquatic communities. However, it remains poorly understood how taxonomic and functional beta diversity correlate with environmental and spatial processes in high-altitude river–lake systems. This study quantified spatial and seasonal variation in phytoplankton beta diversity and identified correlations with environmental and spatial variables across the Qinghai Lake Basin, located on the northeastern Qinghai–Tibet Plateau.
2. We integrated taxonomic and functional approaches to quantify beta diversity patterns using phytoplankton assemblages collected from inflowing tributaries (IT) and the main lake (ML) during summer and autumn. Beta diversity was partitioned into replacement and richness components, and its relationships with environmental and spatial effects were examined using variation partitioning analysis and partial Mantel tests.
3. Taxonomic βtotal and βrepl were marginally higher in tributaries than in the main lake, whereas functional beta diversity and its two components were significantly higher in tributaries. Both taxonomic and functional beta diversity remained stable between seasons in the main lake but increased markedly from summer to autumn in tributaries. Taxonomic beta diversity mainly comprised species replacement (56.65%–69.17%), while functional beta diversity was dominated by richness difference (62.96%–76.19%). Environmental filtering variables, particularly salinity and water temperature, explained a greater portion of community variation than spatial variables.
4. These findings highlight that niche-based environmental filtering and dispersal limitation jointly correlated with phytoplankton beta diversity in this high-altitude river–lake system.
5. Salinity emerged as a particularly influential factor, shaping phytoplankton assemblage variation through strong physiological filtering. The present study highlights the value of integrating both taxonomic and functional perspectives to better elucidate spatio-temporal patterns of phytoplankton biodiversity in high-altitude aquatic ecosystems
Research on optimization method of flotation kinetic model based on molybdenite particle size effect
No full textAbstract
Flotation kinetic models can be applied to describe the flotation process and to predict mineral recoveries. However, the size composition of the target minerals in the feed ore fluctuates considerably, resulting in insufficient accuracy with flotation kinetic models. There have been many studies that focus on the investigation of flotation kinetics with different particle sizes, while the optimization methods for flotation kinetic models based on particle size effects have not been reported. In this paper, flotation tests, optical microscope observations, and particle size analysis were used to identify the reasons for the decrease in accuracy of the flotation kinetic model due to changes in the composition of molybdenite particle size. Additionally, an optimization method for the flotation kinetic model was developed based on the particle size effect. The test results show that the accuracy of the flotation kinetic model for fixed particle size minerals is very high, but the predicted results for flotation recoveries of different particle size mineral mixtures have large deviations. The poor accuracy might be due to the autogenous carrier effect caused by the particle size composition fluctuating considerably. The optimization method for the flotation kinetic model is based on the particle size effect. The model can accurately describe the flotation process of molybdenite with different size compositions of molybdenite and predict the flotation recovery of molybdenite.Abstract
Flotation kinetic models can be applied to describe the flotation process and to predict mineral recoveries. However, the size composition of the target minerals in the feed ore fluctuates considerably, resulting in insufficient accuracy with flotation kinetic models. There have been many studies that focus on the investigation of flotation kinetics with different particle sizes, while the optimization methods for flotation kinetic models based on particle size effects have not been reported. In this paper, flotation tests, optical microscope observations, and particle size analysis were used to identify the reasons for the decrease in accuracy of the flotation kinetic model due to changes in the composition of molybdenite particle size. Additionally, an optimization method for the flotation kinetic model was developed based on the particle size effect. The test results show that the accuracy of the flotation kinetic model for fixed particle size minerals is very high, but the predicted results for flotation recoveries of different particle size mineral mixtures have large deviations. The poor accuracy might be due to the autogenous carrier effect caused by the particle size composition fluctuating considerably. The optimization method for the flotation kinetic model is based on the particle size effect. The model can accurately describe the flotation process of molybdenite with different size compositions of molybdenite and predict the flotation recovery of molybdenite
Visitor perceptions and motivations as drivers of cultural ecosystem services in urban forests: A case study from Helsinki, Finland
No full textAbstract
Cultural Ecosystem Services are gaining increasing attention as motivators for nature conservation and environmental stewardship. However, most assessments focus on tangible, easily measured aspects such as recreation, while more intangible CES—like inspiration, spirituality, or sense of place—and their underlying drivers remain poorly understood. This study examined an array of biophysical and social factors as determinants for CES along a gradient of tangibility.
We used a semi-natural ecosystem—urban forest—as a case to study this question. We surveyed urban forest visitors (n = 241) in the city of Helsinki, Finland to assess CES. We compared the performance of ecosystem features, landscape features, and forest visitors’ demographics, nature-orientation, perception on ecosystem features, and visiting motivation in explaining interlinkages between CES of different tangibility.
Visitor perceptions of ecosystem features and nature-orientation emerged as key explanatory factors of intangible CES, while visiting motivations were more strongly associated with tangible CES such as physical health and recreation. These findings underscore the need to integrate individual human-nature relationships—including sensitivities, preferences, and habitual engagements—into CES assessment. Practically, we suggest that activating both short-term demands and long-term affinities towards nature may enhance the diverse benefits urban nature can provide.Abstract
Cultural Ecosystem Services are gaining increasing attention as motivators for nature conservation and environmental stewardship. However, most assessments focus on tangible, easily measured aspects such as recreation, while more intangible CES—like inspiration, spirituality, or sense of place—and their underlying drivers remain poorly understood. This study examined an array of biophysical and social factors as determinants for CES along a gradient of tangibility.
We used a semi-natural ecosystem—urban forest—as a case to study this question. We surveyed urban forest visitors (n = 241) in the city of Helsinki, Finland to assess CES. We compared the performance of ecosystem features, landscape features, and forest visitors’ demographics, nature-orientation, perception on ecosystem features, and visiting motivation in explaining interlinkages between CES of different tangibility.
Visitor perceptions of ecosystem features and nature-orientation emerged as key explanatory factors of intangible CES, while visiting motivations were more strongly associated with tangible CES such as physical health and recreation. These findings underscore the need to integrate individual human-nature relationships—including sensitivities, preferences, and habitual engagements—into CES assessment. Practically, we suggest that activating both short-term demands and long-term affinities towards nature may enhance the diverse benefits urban nature can provide
Välsigna resan den jag gör - The seal hunters boat and exhibition of the Ostrobothnian Museum as a narrator of the seal hunting culture of the Kvarken area
No full textTutkielmassa tarkastellaan Pohjanmaan museon hylkeenpyyntiesineistöä ja vertaillaan, miten se kuvaa Merenkurkun alueen hylkeenpyyntikulttuuria. Tutkielma toimii myös parannusehdotuksena Pohjanmaan museolle ja sitä voidaan käyttää näyttelytekstien täydentämiseen
CSI2Depth: Spatio-Temporal Depth Images from Wi-Fi CSI Data via Transformer Networks and Conditional Generative Adversarial Networks
No full textAbstract
Depth estimation is important for 3D reconstruction, robotics, and augmented reality. It is also increasingly relevant in Integrated Sensing and Communication (ISAC), where spatial awareness supports adaptive network optimization, beamforming, and digital twins. Traditional depth and RF-based sensors provide accurate measurements but often require active transmissions or specialized hardware. In contrast, Wi-Fi Channel State Information (CSI) enables passive sensing using existing wireless infrastructure. However, classical RF models struggle with multipath propagation, diffraction, and shadowing, limiting depth estimation in complex indoor environments. This study presents a novel proof-of-concept for generating depth maps from raw 5 GHz single-input multiple-output (SIMO) CSI data. A transformer encoder extracts spatio-temporal features from CSI amplitude and phase, which are processed by a conditional generative adversarial network (cGAN) to synthesize depth maps. Unlike prior CSI-based work focused on activity recognition or point cloud estimation, depth maps provide structured outputs that are computationally efficient and compatible with computer vision techniques. Evaluated on the public MM-Fi dataset, the model captures temporal depth variations associated with scene geometry and obstructions. The results demonstrate the feasibility of passive depth estimation from CSI under stable infrastructure with adequate signal quality and antenna diversity, contributing to the development of ISAC-enabled wireless systems. The code is available at: https://github.com/Arritmic/csi2depth.Abstract
Depth estimation is important for 3D reconstruction, robotics, and augmented reality. It is also increasingly relevant in Integrated Sensing and Communication (ISAC), where spatial awareness supports adaptive network optimization, beamforming, and digital twins. Traditional depth and RF-based sensors provide accurate measurements but often require active transmissions or specialized hardware. In contrast, Wi-Fi Channel State Information (CSI) enables passive sensing using existing wireless infrastructure. However, classical RF models struggle with multipath propagation, diffraction, and shadowing, limiting depth estimation in complex indoor environments. This study presents a novel proof-of-concept for generating depth maps from raw 5 GHz single-input multiple-output (SIMO) CSI data. A transformer encoder extracts spatio-temporal features from CSI amplitude and phase, which are processed by a conditional generative adversarial network (cGAN) to synthesize depth maps. Unlike prior CSI-based work focused on activity recognition or point cloud estimation, depth maps provide structured outputs that are computationally efficient and compatible with computer vision techniques. Evaluated on the public MM-Fi dataset, the model captures temporal depth variations associated with scene geometry and obstructions. The results demonstrate the feasibility of passive depth estimation from CSI under stable infrastructure with adequate signal quality and antenna diversity, contributing to the development of ISAC-enabled wireless systems. The code is available at: https://github.com/Arritmic/csi2depth