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Fatigue Strength and Impact Toughness on High Speed Build of PBF-LB AlSi10Mg
No full textAbstract
The process of component production has been transformed by additive manufacturing (AM), offering intricate geometries with unprecedented complexity. Laser powder bed fusion (PBF-LB) is a versatile technique for fabricating precise, customized metallic parts. However, rapid solidification during the printing can induce significant anisotropy, affecting microstructure and mechanical properties. Understanding the impact of build orientation and process parameters on AM component properties is crucial for optimization and reliability. Previous studies have shed light on the properties of PBF-LB AlSi10Mg alloy such as the factors influencing mechanical strength, fatigue life, and impact toughness. Current work further examines the influence of print orientation on microstructure and mechanical characteristics when high productivity is used on the manufacturing, analyzing specimens for tensile testing, impact toughness, and fatigue strength. Results reveal correlations between structural anisotropy and mechanical behavior, offering insights for optimizing AlSi10Mg component fabrication.Abstract
The process of component production has been transformed by additive manufacturing (AM), offering intricate geometries with unprecedented complexity. Laser powder bed fusion (PBF-LB) is a versatile technique for fabricating precise, customized metallic parts. However, rapid solidification during the printing can induce significant anisotropy, affecting microstructure and mechanical properties. Understanding the impact of build orientation and process parameters on AM component properties is crucial for optimization and reliability. Previous studies have shed light on the properties of PBF-LB AlSi10Mg alloy such as the factors influencing mechanical strength, fatigue life, and impact toughness. Current work further examines the influence of print orientation on microstructure and mechanical characteristics when high productivity is used on the manufacturing, analyzing specimens for tensile testing, impact toughness, and fatigue strength. Results reveal correlations between structural anisotropy and mechanical behavior, offering insights for optimizing AlSi10Mg component fabrication
Insights into chondrocyte populations in cartilaginous tissues at the single-cell level
No full textAbstract
Chondrocyte biology is being revolutionized by single-cell multi-omics technologies, revealing cellular heterogeneity within cartilaginous tissues. Although past research has implicated cellular heterogeneity in chondrocyte populations, advances over the past decade in single-cell transcriptomics now enable a more granular, functionally annotated classification of chondrocyte subtypes. These analyses provide crucial insights into the role of these subtypes in cartilage formation, maintenance and disease progression. Chondrocyte populations are implicated in tissue homeostasis, pathogenesis and responses to external stimuli, including pro-inflammatory mediators and novel therapeutic agents. This knowledge opens pathways for developing targeted treatments for diseases such as osteoarthritis and intervertebral disc disease. Insights into the molecular signatures of disease-critical chondrocyte populations provide a foundation for biomarker discovery and therapeutic targeting, and there are exciting opportunities for leveraging these findings to progress regenerative therapies. Spatial and temporal profiling of cellular markers, behaviour and metabolic activity will enhance understanding of disease pathogenesis and chondrosenescence and could possibly enable early intervention for osteoarthritis, thereby preventing irreversible joint damage. Future research must integrate advanced single-cell techniques with computational modelling to unravel the dynamic interplay of chondrocyte populations. These efforts could transform precision medicine in rheumatology, addressing the unmet clinical needs in cartilage-related diseases.Abstract
Chondrocyte biology is being revolutionized by single-cell multi-omics technologies, revealing cellular heterogeneity within cartilaginous tissues. Although past research has implicated cellular heterogeneity in chondrocyte populations, advances over the past decade in single-cell transcriptomics now enable a more granular, functionally annotated classification of chondrocyte subtypes. These analyses provide crucial insights into the role of these subtypes in cartilage formation, maintenance and disease progression. Chondrocyte populations are implicated in tissue homeostasis, pathogenesis and responses to external stimuli, including pro-inflammatory mediators and novel therapeutic agents. This knowledge opens pathways for developing targeted treatments for diseases such as osteoarthritis and intervertebral disc disease. Insights into the molecular signatures of disease-critical chondrocyte populations provide a foundation for biomarker discovery and therapeutic targeting, and there are exciting opportunities for leveraging these findings to progress regenerative therapies. Spatial and temporal profiling of cellular markers, behaviour and metabolic activity will enhance understanding of disease pathogenesis and chondrosenescence and could possibly enable early intervention for osteoarthritis, thereby preventing irreversible joint damage. Future research must integrate advanced single-cell techniques with computational modelling to unravel the dynamic interplay of chondrocyte populations. These efforts could transform precision medicine in rheumatology, addressing the unmet clinical needs in cartilage-related diseases
Mitä käytännön työssä voidaan oppia rekisteritiedoista?
No full textSuomi ja muut Pohjoismaat ovat olleet terveydenhuollon rekisteritutkimuksen edelläkävijämaita reippaasti puolet Aikakauskirjan 140-vuotisesta taipaleesta. Monen sairauden epidemiologiaa koskevat perustiedot nojautuvat rekisteritietoihin: jo vuosikymmeniä sitten rekisterit kertoivat esimerkiksi syöpätautien ennusteesta tai kansanterveysohjelmien kuten Pohjois-Karjala-projektin vaikutuksista. Rekisteritietojen avulla voidaan tehdä vuosikymmeniä kestäviä, tarvittaessa ylisukupolvisia seurantatutkimuksia ja tutkia toiminnan tehokkuutta vertailemalla esimerkiksi hyvinvointialueita. Haluttaessa tietoa elintavoista, elämänlaadusta, arvoista tai asenteista taikka biologisia näytteitä rekisteritietoja voidaan yhdistää kliinisen tutkimuksen, syntymäkohortin tai biopankin tietoihin. Näin tehdään muun muassa käynnistyvässä Huomisen Suomi -syntymäkohortissa, jossa vuosina 2025-2029 syntyvistä noin 200 000 lapsesta ja heidän perheistään kerätään kansallisten rekisterien tietoja, joita rikastetaan biologisilla näytteillä sekä lyhyillä kyselyillä.Suomi ja muut Pohjoismaat ovat olleet terveydenhuollon rekisteritutkimuksen edelläkävijämaita reippaasti puolet Aikakauskirjan 140-vuotisesta taipaleesta. Monen sairauden epidemiologiaa koskevat perustiedot nojautuvat rekisteritietoihin: jo vuosikymmeniä sitten rekisterit kertoivat esimerkiksi syöpätautien ennusteesta tai kansanterveysohjelmien kuten Pohjois-Karjala-projektin vaikutuksista. Rekisteritietojen avulla voidaan tehdä vuosikymmeniä kestäviä, tarvittaessa ylisukupolvisia seurantatutkimuksia ja tutkia toiminnan tehokkuutta vertailemalla esimerkiksi hyvinvointialueita. Haluttaessa tietoa elintavoista, elämänlaadusta, arvoista tai asenteista taikka biologisia näytteitä rekisteritietoja voidaan yhdistää kliinisen tutkimuksen, syntymäkohortin tai biopankin tietoihin. Näin tehdään muun muassa käynnistyvässä Huomisen Suomi -syntymäkohortissa, jossa vuosina 2025-2029 syntyvistä noin 200 000 lapsesta ja heidän perheistään kerätään kansallisten rekisterien tietoja, joita rikastetaan biologisilla näytteillä sekä lyhyillä kyselyillä
Local environmental conditions and loss of river-lake connection shape the ecological uniqueness of molluscan assemblages
No full textAbstract
This study focused on a lake dataset to explore the effects of river–lake disconnection on the relative contributions of sites (LCBD) and species (SCBD) to beta diversity of molluscan assemblages. We compared the relationship between LCBD and its two components (i.e., species replacement: ReplLCBD, and richness difference: RichDiffLCBD) with taxonomic richness (i.e., the number of total and rare species) between connected lakes (CLs) and disconnected lakes (DLs). We further identified key environmental variables driving LCBD and explored relationships of SCBD with species occupancy and functional features. Our results indicated that taxonomic richness and RichDiffLCBD were all significantly higher in CLs than in DLs, whereas ReplLCBD showed the opposite pattern. Moreover, the correlation between LCBD and taxonomic richness showed an opposite trend between CLs and DLs. In CLs, high ecological uniqueness was typically associated with high taxonomic richness. By contrast, severely impacted DLs were characterized by lower species richness and high LCBD values. Environmental factors associated with connectivity were most significant for ReplLCBD and RichDiffLCBD. Moreover, SCBD showed a hump-shaped relationship with species occupancy and was poorly explained by functional traits. In conclusion, understanding the determinants of LCBD and SCBD is important for addressing lake assessment, biological conservation and ecological restoration.Abstract
This study focused on a lake dataset to explore the effects of river–lake disconnection on the relative contributions of sites (LCBD) and species (SCBD) to beta diversity of molluscan assemblages. We compared the relationship between LCBD and its two components (i.e., species replacement: ReplLCBD, and richness difference: RichDiffLCBD) with taxonomic richness (i.e., the number of total and rare species) between connected lakes (CLs) and disconnected lakes (DLs). We further identified key environmental variables driving LCBD and explored relationships of SCBD with species occupancy and functional features. Our results indicated that taxonomic richness and RichDiffLCBD were all significantly higher in CLs than in DLs, whereas ReplLCBD showed the opposite pattern. Moreover, the correlation between LCBD and taxonomic richness showed an opposite trend between CLs and DLs. In CLs, high ecological uniqueness was typically associated with high taxonomic richness. By contrast, severely impacted DLs were characterized by lower species richness and high LCBD values. Environmental factors associated with connectivity were most significant for ReplLCBD and RichDiffLCBD. Moreover, SCBD showed a hump-shaped relationship with species occupancy and was poorly explained by functional traits. In conclusion, understanding the determinants of LCBD and SCBD is important for addressing lake assessment, biological conservation and ecological restoration
Behavior and Mechanisms of Lead and Cadmium Ions During the Zinc Electrowinning in Ammonia-Based Systems
No full textAbstract
The ammonia-based zinc extraction process has gained increasing application due to the characteristics of suitable treatment of low-grade zinc oxide resources, high purification efficiency of leaching solution, and less waste discharge. However, studies on the impact of metal impurity ions during the zinc electrodeposition process in ammonia-based systems remain relatively limited. This paper systematically investigates the effects of Pb and Cd on zinc electrodeposition. The results indicate that in the zinc electrodeposition system, the impurity lead exists in forms such as Pb2+, PbCl+, Pb2(OH)42+, and PbOH+, while cadmium exists as Cd2+, Cd(NH3)22+, Cd(NH3)32+, and Cd(NH3)42+. Further electrochemical experiments reveal that with increasing concentrations of Pb and Cd in the electrolyte, the nucleation overpotential decreases, the corrosion current density increases, and the corrosion rate accelerates, which progressively hinders the deposition of cathodic zinc. Additionally, high concentrations of Pb and Cd in the electrodeposition system lead to cathodic corrosion, resulting in rough, polycrystalline dendritic cathodic zinc that is difficult to strip and inhibit zinc deposition on the electrode surface. When the Pb and Cd concentration is 0.1 g/L, the current efficiency reaches its maximum value of 95.48 and 93.86 pct accordingly with the power consumption of 2496.57 and 2458.69 kWh/t. This study elucidates the impact of impurity ions on zinc electrodeposition in the ammonia-based zinc extraction process and identifies the beneficial effects of appropriate Pb and Cd concentrations on electrodeposition efficiency. This research provides a theoretical foundation and introduces an innovative method for controlling the concentration and establishing industry standards for impurity ion content in the electrolyte used in the industrial production of ammonia zinc smelting.Abstract
The ammonia-based zinc extraction process has gained increasing application due to the characteristics of suitable treatment of low-grade zinc oxide resources, high purification efficiency of leaching solution, and less waste discharge. However, studies on the impact of metal impurity ions during the zinc electrodeposition process in ammonia-based systems remain relatively limited. This paper systematically investigates the effects of Pb and Cd on zinc electrodeposition. The results indicate that in the zinc electrodeposition system, the impurity lead exists in forms such as Pb2+, PbCl+, Pb2(OH)42+, and PbOH+, while cadmium exists as Cd2+, Cd(NH3)22+, Cd(NH3)32+, and Cd(NH3)42+. Further electrochemical experiments reveal that with increasing concentrations of Pb and Cd in the electrolyte, the nucleation overpotential decreases, the corrosion current density increases, and the corrosion rate accelerates, which progressively hinders the deposition of cathodic zinc. Additionally, high concentrations of Pb and Cd in the electrodeposition system lead to cathodic corrosion, resulting in rough, polycrystalline dendritic cathodic zinc that is difficult to strip and inhibit zinc deposition on the electrode surface. When the Pb and Cd concentration is 0.1 g/L, the current efficiency reaches its maximum value of 95.48 and 93.86 pct accordingly with the power consumption of 2496.57 and 2458.69 kWh/t. This study elucidates the impact of impurity ions on zinc electrodeposition in the ammonia-based zinc extraction process and identifies the beneficial effects of appropriate Pb and Cd concentrations on electrodeposition efficiency. This research provides a theoretical foundation and introduces an innovative method for controlling the concentration and establishing industry standards for impurity ion content in the electrolyte used in the industrial production of ammonia zinc smelting
How do users revise architectural related questions on stack overflow: an empirical study
No full textAbstract
Technical Questions and Answers (Q&A) sites, such as Stack Overflow (SO), accumulate a significant variety of information related to software development in posts from users. To ensure the quality of this information, SO encourages its users to review posts through various mechanisms (e.g., question and answer revision processes). Although Architecture-Related Posts (ARPs) communicate architectural information that has a system-wide impact on development, little is known about how SO users revise information shared in ARPs. To fill this gap, we conducted an empirical study to understand how users revise Architecture-Related Questions (ARQs) on SO. By following a rigorous procedure consisting of data collection and filtering, we manually checked 13,205 ARPs and finally identified 4,114 ARQs that contain revision information. Our main findings are that: (1) The revision of ARQs is not prevalent in SO, and an ARQ revision starts soon after this question is posted (i.e., from 1 minute onward). Moreover, the revision of an ARQ occurs before and after this question receives its first answer/architecture solution, with most revisions beginning before the first architecture solution is posted. Both Question Creators (QCs) and non-QCs actively participate in ARQ revisions, with most revisions being made by QCs. (2) A variety of information (14 categories) is missed and further provided in ARQs after being posted, among which design context, component dependency, and architecture concern are dominant information. (3) Clarify the understanding of architecture under design and improve the readability of architecture problem are the two major purposes of the further provided information in ARQs. (4) The further provided information in ARQs has several impacts on the quality of architecture solutions, including making architecture solution useful, making architecture solution informative, making architecture solution relevant, among others. The categorization of ARQ revisions was perceived by practitioners as meaningful, reliable, and comprehensive in capturing how ARQs evolve on SO. Participants confirmed that the categories effectively reflect common types, purposes, and impacts of ARQ revisions. Our findings (1) provide researchers with new directions, such as the techniques and tools to facilitate SO users revising ARQs, and (2) provide SO users with suggestions and a structured template when asking and revising ARQs with the likelihood of getting quality architecture solutions.Abstract
Technical Questions and Answers (Q&A) sites, such as Stack Overflow (SO), accumulate a significant variety of information related to software development in posts from users. To ensure the quality of this information, SO encourages its users to review posts through various mechanisms (e.g., question and answer revision processes). Although Architecture-Related Posts (ARPs) communicate architectural information that has a system-wide impact on development, little is known about how SO users revise information shared in ARPs. To fill this gap, we conducted an empirical study to understand how users revise Architecture-Related Questions (ARQs) on SO. By following a rigorous procedure consisting of data collection and filtering, we manually checked 13,205 ARPs and finally identified 4,114 ARQs that contain revision information. Our main findings are that: (1) The revision of ARQs is not prevalent in SO, and an ARQ revision starts soon after this question is posted (i.e., from 1 minute onward). Moreover, the revision of an ARQ occurs before and after this question receives its first answer/architecture solution, with most revisions beginning before the first architecture solution is posted. Both Question Creators (QCs) and non-QCs actively participate in ARQ revisions, with most revisions being made by QCs. (2) A variety of information (14 categories) is missed and further provided in ARQs after being posted, among which design context, component dependency, and architecture concern are dominant information. (3) Clarify the understanding of architecture under design and improve the readability of architecture problem are the two major purposes of the further provided information in ARQs. (4) The further provided information in ARQs has several impacts on the quality of architecture solutions, including making architecture solution useful, making architecture solution informative, making architecture solution relevant, among others. The categorization of ARQ revisions was perceived by practitioners as meaningful, reliable, and comprehensive in capturing how ARQs evolve on SO. Participants confirmed that the categories effectively reflect common types, purposes, and impacts of ARQ revisions. Our findings (1) provide researchers with new directions, such as the techniques and tools to facilitate SO users revising ARQs, and (2) provide SO users with suggestions and a structured template when asking and revising ARQs with the likelihood of getting quality architecture solutions
Virtual Reality to Improve Joint Attention Skills in Children With Autism: Protocol for a Randomized Controlled Trial
No full textAbstract
Joint attention (JA) deficits are frequently one of the earliest indicators of autism spectrum disorder (ASD), making them a crucial focus for early interventions. Despite the importance of JA, existing interventions often face barriers such as high costs, limited adaptability, and resource demands. Virtual reality (VR) offers a novel, immersive, and flexible approach that may overcome these challenges by creating engaging and individualized environments for children with ASD. This protocol describes a randomized controlled trial evaluating a VR-based intervention designed to improve JA and related social-communication skills in school-aged autistic children. Participants will receive either VR therapy plus standard interventions or a sham VR condition plus standard interventions. The primary outcome is JA performance, with secondary outcomes focusing on broader social communication abilities. By testing this innovative, technology-supported intervention in naturalistic school settings, the trial aims to provide high-quality evidence on the feasibility and potential impact of VR as a supplemental therapy for autism. Key limitations include the relatively small sample size and short-term follow-up, which will guide recommendations for larger, long-term studies.Abstract
Joint attention (JA) deficits are frequently one of the earliest indicators of autism spectrum disorder (ASD), making them a crucial focus for early interventions. Despite the importance of JA, existing interventions often face barriers such as high costs, limited adaptability, and resource demands. Virtual reality (VR) offers a novel, immersive, and flexible approach that may overcome these challenges by creating engaging and individualized environments for children with ASD. This protocol describes a randomized controlled trial evaluating a VR-based intervention designed to improve JA and related social-communication skills in school-aged autistic children. Participants will receive either VR therapy plus standard interventions or a sham VR condition plus standard interventions. The primary outcome is JA performance, with secondary outcomes focusing on broader social communication abilities. By testing this innovative, technology-supported intervention in naturalistic school settings, the trial aims to provide high-quality evidence on the feasibility and potential impact of VR as a supplemental therapy for autism. Key limitations include the relatively small sample size and short-term follow-up, which will guide recommendations for larger, long-term studies
Experiences Using Patient and Public Involvement in Digital Health Research for Multiple Sclerosis
No full textAbstract
Patient and public involvement (PPI) is increasingly used for improving quality of the research. There are many barriers in translating PPI into practice, including lacking examples of good practices. Frameworks that have been developed in one setting do not readily transfer to other settings. In this paper, we examine the implementation of PPI in the context of a digital health research project that explores the design, development and use of mHealth for persons with Multiple Sclerosis taking an iterative user-centered design approach.Abstract
Patient and public involvement (PPI) is increasingly used for improving quality of the research. There are many barriers in translating PPI into practice, including lacking examples of good practices. Frameworks that have been developed in one setting do not readily transfer to other settings. In this paper, we examine the implementation of PPI in the context of a digital health research project that explores the design, development and use of mHealth for persons with Multiple Sclerosis taking an iterative user-centered design approach
mmWave-antennin suunnittelu 5G-matkapuhelimissa
No full text5G wireless technology operates across a wide range of frequency bands, classified into Frequency Range 1 (FR1) and Frequency Range 2 (FR2). FR1 includes frequencies be-low 7.225 GHz, many of which are also utilised in existing 4G systems. In contrast, FR2 encompasses millimetre-wave (mmWave) bands, which enable data transfer rates of up to 10 Gbit/s—nearly 100 times faster than 4G. However, integrating multiple antennas within the limited space of modern 5G mobile devices presents a significant challenge for antenna designers.
This thesis addresses these challenges by first examining the key differences between sub-6 GHz and mmWave antennas in mobile phones, with a particular focus on the de-sign trade-offs involving antenna size, efficiency, and bandwidth. The study also ex-plores state-of-the-art mmWave antenna design solutions, drawing from both academic research and industry advancements. Furthermore, this thesis discusses and compares various proposed solutions while also reviewing Specific Absorption Rate (SAR) stand-ards and regulatory limits for both sub-6 GHz and mmWave frequencies, ensuring compliance with global safety regulations.
By providing a comprehensive analysis of 5G antenna design challenges and potential solutions, this thesis aims to contribute to the development of efficient and practical mmWave antennas for next-generation mobile devices
Effectiveness of nature-based group intervention in loneliness and health-related quality-of-life in lonely older adults living in assisted living facilities-a randomised controlled trial
No full textAbstract
Introduction:
Nature experienced with peers may mitigate the harmful outcomes of loneliness on health and wellbeing. The H2020 RECETAS ‘Friends in Nature (FiN)-Helsinki’ group intervention for lonely older adults in Helsinki assisted living facilities (ALFs) aimed to investigate the effects on participants’ loneliness and health-related quality of life (HRQoL). We also examined factors influencing effects between the intervention and the outcomes.
Methods:
Lonely participants were recruited from 22 ALFs in Helsinki area, Finland and randomised into two groups: (i) nature-based group intervention once a week for 9 weeks (n = 162) and (ii) usual care (n = 157). Loneliness (modified De Jong Gierveld Loneliness Scale = mDJGLS) and HRQoL (15D) were assessed as the primary outcomes at baseline, 3, 6 and 12 months.
Results:
Most participants (mean age 83 years, 73% women) were living with frailty (66%) and had dementia (55%). Whilst loneliness was reduced in the intervention group at three months (mean change −2.2 points [95% confidence interval (CI) −3.5 to −0.9] in mDJGLS, it remained at baseline level amongst controls (mean change −0.1 (95% CI −1.4 to 0.9); P = .025 between groups). During the 6- and 12-month follow-ups the difference was reduced. No difference emerged between groups in changes of HRQoL according to the 15D. However, the ‘sleep’ dimension in 15D improved in the intervention relative to controls during the 12-month follow-up. Frequent attendance in group sessions and extended time spent outdoors affected effects on both HRQoL and loneliness. High self-efficacy at baseline influenced effect on both HRQoL and mDJGLS. Being male, 20 and exhibiting a high Nature Connection Index at baseline influenced the magnitude of effect in reducing loneliness.
Conclusions:
Group intervention with nature contacts had favourable effects on loneliness and sleep amongst physically and cognitively frail, lonely older adults in ALFs.
Trial registration:
ClinicalTrials.gov, ID: NCT05507684. Registration 19/08/2022.Abstract
Introduction:
Nature experienced with peers may mitigate the harmful outcomes of loneliness on health and wellbeing. The H2020 RECETAS ‘Friends in Nature (FiN)-Helsinki’ group intervention for lonely older adults in Helsinki assisted living facilities (ALFs) aimed to investigate the effects on participants’ loneliness and health-related quality of life (HRQoL). We also examined factors influencing effects between the intervention and the outcomes.
Methods:
Lonely participants were recruited from 22 ALFs in Helsinki area, Finland and randomised into two groups: (i) nature-based group intervention once a week for 9 weeks (n = 162) and (ii) usual care (n = 157). Loneliness (modified De Jong Gierveld Loneliness Scale = mDJGLS) and HRQoL (15D) were assessed as the primary outcomes at baseline, 3, 6 and 12 months.
Results:
Most participants (mean age 83 years, 73% women) were living with frailty (66%) and had dementia (55%). Whilst loneliness was reduced in the intervention group at three months (mean change −2.2 points [95% confidence interval (CI) −3.5 to −0.9] in mDJGLS, it remained at baseline level amongst controls (mean change −0.1 (95% CI −1.4 to 0.9); P = .025 between groups). During the 6- and 12-month follow-ups the difference was reduced. No difference emerged between groups in changes of HRQoL according to the 15D. However, the ‘sleep’ dimension in 15D improved in the intervention relative to controls during the 12-month follow-up. Frequent attendance in group sessions and extended time spent outdoors affected effects on both HRQoL and loneliness. High self-efficacy at baseline influenced effect on both HRQoL and mDJGLS. Being male, 20 and exhibiting a high Nature Connection Index at baseline influenced the magnitude of effect in reducing loneliness.
Conclusions:
Group intervention with nature contacts had favourable effects on loneliness and sleep amongst physically and cognitively frail, lonely older adults in ALFs.
Trial registration:
ClinicalTrials.gov, ID: NCT05507684. Registration 19/08/2022