OuluREPO University of Oulu repository
Not a member yet
54977 research outputs found
Sort by
Muscle biopsy and mitochondrial disease criteria as diagnostic tools for paediatric patients presenting with neuromuscular phenotypes: highlighting the role of secondary mitochondrial dysfunction
No full textAbstract
This study evaluated the diagnostic utility of muscle biopsy and the performance of the Nijmegen and modified Walker criteria in a real-life paediatric cohort with neuromuscular symptoms. A retrospective review at Oulu University Hospital included 220 paediatric patients with unexplained neuromuscular symptoms who underwent muscle biopsy between 1990 and 2024. Clinical data were collected, and patients were classified using both criteria. A genetic diagnosis was confirmed in 58 patients (26 %): 12 with primary mitochondrial diseases (21 %), 17 with secondary mitochondrial dysfunction (29 %), and 29 with other neuromuscular disorders (50 %). OXPHOS activities were measured in 189 patients (86 %); 49 (26 %) showed decreased activity, including 13 with genetic confirmation. Electron microscopy (n=175) showed mitochondrial abnormalities in 49 patients (28 %); 75 % of these had mitochondrial disease. The modified Walker criteria outperformed the Nijmegen (sensitivity 75 % vs 50 %; specificity 100 % vs 98 %). Mean Nijmegen scores were significantly higher in primary mitochondrial disease (p<0.05), also compared with patients with secondary dysfunction. In conclusion, muscle biopsy and mitochondrial disease criteria remain valuable tools distinguishing primary mitochondrial diseases. This study highlights the role of secondary mitochondrial dysfunction in non-mitochondrial genetic conditions and metabolic diseases with undefined genetic aetiologies waiting to be identified in the future.Abstract
This study evaluated the diagnostic utility of muscle biopsy and the performance of the Nijmegen and modified Walker criteria in a real-life paediatric cohort with neuromuscular symptoms. A retrospective review at Oulu University Hospital included 220 paediatric patients with unexplained neuromuscular symptoms who underwent muscle biopsy between 1990 and 2024. Clinical data were collected, and patients were classified using both criteria. A genetic diagnosis was confirmed in 58 patients (26 %): 12 with primary mitochondrial diseases (21 %), 17 with secondary mitochondrial dysfunction (29 %), and 29 with other neuromuscular disorders (50 %). OXPHOS activities were measured in 189 patients (86 %); 49 (26 %) showed decreased activity, including 13 with genetic confirmation. Electron microscopy (n=175) showed mitochondrial abnormalities in 49 patients (28 %); 75 % of these had mitochondrial disease. The modified Walker criteria outperformed the Nijmegen (sensitivity 75 % vs 50 %; specificity 100 % vs 98 %). Mean Nijmegen scores were significantly higher in primary mitochondrial disease (p<0.05), also compared with patients with secondary dysfunction. In conclusion, muscle biopsy and mitochondrial disease criteria remain valuable tools distinguishing primary mitochondrial diseases. This study highlights the role of secondary mitochondrial dysfunction in non-mitochondrial genetic conditions and metabolic diseases with undefined genetic aetiologies waiting to be identified in the future
Effective factors for the adoption of IoT applications in nursing care: A theoretical framework for smart healthcare
No full textAbstract
The utilization of the Internet of Things (IoT) presents a promising opportunity for the healthcare industry which is continuously expanding and persistently aspiring to enhance the quality of medical services and reduce its operational costs through the implementation of new technologies. Despite the proven benefits of utilizing IoT-based technologies, its integration in the healthcare sector is minimal, particularly in nursing care. The purpose of this study is to establish a conceptual model to guide program designers and implementation leaders in evaluating the adoption of IoT products and services in nursing care, from the perspective of nurses. The study employed an empirical quantitative research design utilizing a structured online questionnaire to collect data from a convenience sample of nursing staff gathered data were subjected to statistical analysis using Statistical Package for the Social Sciences (SPSS) and Structural Equation Modeling Partial Least Square (SEM-PLS). Data analysis led to the establishment of a framework to identify factors influencing the integration of IoT and barriers that may impede its adoption in nursing care. The study makes a valuable contribution to academia by addressing a gap in the existing literature relating to the adoption of IoT in medical services, particularly in nursing care, and providing a novel theoretical framework that encompasses effective factors for the integration of IoT in medical care. This model provides deep insight and guidance to healthcare industry leaders, system developers, and nursing professionals to improve program design and implementation of IoT applications in healthcare. In addition, the model guides building engineering in the planning and design of medical facilities aligned with the IoT technologies and its physical environment. Finally, the study paved the way for further research exploring the implementation of IoT-based technologies and expanding the model to other stakeholders and functions within medical departments as well as other industries.Abstract
The utilization of the Internet of Things (IoT) presents a promising opportunity for the healthcare industry which is continuously expanding and persistently aspiring to enhance the quality of medical services and reduce its operational costs through the implementation of new technologies. Despite the proven benefits of utilizing IoT-based technologies, its integration in the healthcare sector is minimal, particularly in nursing care. The purpose of this study is to establish a conceptual model to guide program designers and implementation leaders in evaluating the adoption of IoT products and services in nursing care, from the perspective of nurses. The study employed an empirical quantitative research design utilizing a structured online questionnaire to collect data from a convenience sample of nursing staff gathered data were subjected to statistical analysis using Statistical Package for the Social Sciences (SPSS) and Structural Equation Modeling Partial Least Square (SEM-PLS). Data analysis led to the establishment of a framework to identify factors influencing the integration of IoT and barriers that may impede its adoption in nursing care. The study makes a valuable contribution to academia by addressing a gap in the existing literature relating to the adoption of IoT in medical services, particularly in nursing care, and providing a novel theoretical framework that encompasses effective factors for the integration of IoT in medical care. This model provides deep insight and guidance to healthcare industry leaders, system developers, and nursing professionals to improve program design and implementation of IoT applications in healthcare. In addition, the model guides building engineering in the planning and design of medical facilities aligned with the IoT technologies and its physical environment. Finally, the study paved the way for further research exploring the implementation of IoT-based technologies and expanding the model to other stakeholders and functions within medical departments as well as other industries
Priority recovering of lithium from spent lithium-ion battery cathode powder by pyrolysis reduction of Bidens pilosa
Get PDFAbstract
In this paper, the invasive plant Bidens pilosa was used as a carbon material to roast and reduce the cathode powder of spent ternary lithium-ion batteries (LiNixCoyMn1-x-yO2), to alleviate lithium resource scarcity and the problems of large spent of batteries which is harmful to the environment. The transition metals in the cathode powder were reduced to Ni, Co, and MnO, respectively, and the Li element in the cathode powder was reacted to generate Li2CO3. The experiment explored the reduction effect of high valent metals in spent lithium-ion batteries at different roasting temperatures and biomass ratios, and the impact of different time on the leaching of Li element. Results showed that the optimal experimental conditions of reduction roasting were as follows: temperature 700 °C, biomass ratio 20%. The leaching efficiency of Li obtained under optimal roasting conditions through leaching was 94.15%. TG-DSC/MS, XRD, XPS, SEM, and other instruments characterized the experimental results. This method not only efficiently converts Bidens pilosa into a carbon-reducing agent and solves the problem of plant invasion, but also promotes the decomposition of spent cathode powder, reduces high valence metals to single metals and low valence oxides, and generates Li2CO3 through reaction, which can selectively extract lithium element and reduce the amount of reagent added and the use of reducing agent in the subsequent leaching process.Abstract
In this paper, the invasive plant Bidens pilosa was used as a carbon material to roast and reduce the cathode powder of spent ternary lithium-ion batteries (LiNixCoyMn1-x-yO2), to alleviate lithium resource scarcity and the problems of large spent of batteries which is harmful to the environment. The transition metals in the cathode powder were reduced to Ni, Co, and MnO, respectively, and the Li element in the cathode powder was reacted to generate Li2CO3. The experiment explored the reduction effect of high valent metals in spent lithium-ion batteries at different roasting temperatures and biomass ratios, and the impact of different time on the leaching of Li element. Results showed that the optimal experimental conditions of reduction roasting were as follows: temperature 700 °C, biomass ratio 20%. The leaching efficiency of Li obtained under optimal roasting conditions through leaching was 94.15%. TG-DSC/MS, XRD, XPS, SEM, and other instruments characterized the experimental results. This method not only efficiently converts Bidens pilosa into a carbon-reducing agent and solves the problem of plant invasion, but also promotes the decomposition of spent cathode powder, reduces high valence metals to single metals and low valence oxides, and generates Li2CO3 through reaction, which can selectively extract lithium element and reduce the amount of reagent added and the use of reducing agent in the subsequent leaching process
Value Creation from Waste Through Remanufacturing: Understanding Barriers from the Perspective of Business Model Dimensions
Get PDFAbstract
Waste management is an integral part of the circular economy that helps create value from end-of-life (EoL) products. Effective approaches such as 3R (reusing, remanufacturing, and recycling) enhance the use of discarded EoL products. Remanufacturing is an effort that improves waste management by extracting the highest possible value from EoL products and requalifying them for a like new product. This paper examines how a heavy vehicle manufacturer can create value from EoL products by modifying business model (BM) dimensions through remanufacturing. This study has been conducted from the perspective of barriers to implementing remanufacturing. The results of the thematic analysis provide an understanding of the effects of barriers on the BM dimensions and modifications that are needed in these dimensions. Developing this understanding can assist manufacturers in modifying current BM and creating sustainable value through remanufacturing. BM modification involves incorporating modular architecture into product development along with the value proposition dimension. In addition, developing value creation and value delivery dimensions emphasizes the importance of integrating circularity features into supply chain configurations. In this light, the results suggest that by moving toward circular supply chains, manufacturers can manage waste, reduce component downgrading rates, effectively extract value from EoL products, and benefit from reduced reverse logistics costs.Abstract
Waste management is an integral part of the circular economy that helps create value from end-of-life (EoL) products. Effective approaches such as 3R (reusing, remanufacturing, and recycling) enhance the use of discarded EoL products. Remanufacturing is an effort that improves waste management by extracting the highest possible value from EoL products and requalifying them for a like new product. This paper examines how a heavy vehicle manufacturer can create value from EoL products by modifying business model (BM) dimensions through remanufacturing. This study has been conducted from the perspective of barriers to implementing remanufacturing. The results of the thematic analysis provide an understanding of the effects of barriers on the BM dimensions and modifications that are needed in these dimensions. Developing this understanding can assist manufacturers in modifying current BM and creating sustainable value through remanufacturing. BM modification involves incorporating modular architecture into product development along with the value proposition dimension. In addition, developing value creation and value delivery dimensions emphasizes the importance of integrating circularity features into supply chain configurations. In this light, the results suggest that by moving toward circular supply chains, manufacturers can manage waste, reduce component downgrading rates, effectively extract value from EoL products, and benefit from reduced reverse logistics costs
Multi-physical field coupling modeling of microwave heating and reduction behavior of zinc oxide
No full textAbstract
Microwave heating provides a cleaner pyrometallurgical method for separating zinc from electric arc furnace dust (EAFD, a solid waste generated during steel production with excellent dielectric properties). Despite its undisputed heating efficiency, the impact of microwave heating characteristics on the zinc removal process from EAFD remains unclear. This paper focuses on ZnO, one of the primary components of EAFD, and develops an electromagnetic-thermal-chemical reaction model to analyze the effects of microwave power and graphite addition on heating behavior, reduction reactions, field distributions, and reaction kinetics. The results indicate that the heat generated from the interaction between microwaves and materials exhibits inherent non-uniformity, leading to the localized thermal effect and making the error of general temperature measurement methods. Increasing microwave power and adding graphite enhance heating efficiency and promote the reduction reaction but also result in significant internal-external temperature disparity and worse temperature distribution. At 1000 W, with 1.2 times the stoichiometric amount of graphite addition, the temperature measurement error reaches approximately 200 °C, potentially affecting the kinetic results to a certain degree. The non-isothermal kinetics results from simulations indicate that the localized thermal region exhibits a lower average activation energy of 47.5 kJ/mol compared to experimental results, suggesting that the lower activation energy of the ZnO reduction reaction during microwave heating is primarily caused by the localized thermal effect rather than the non-thermal effect. Additionally, in the energy distribution, the higher proportion of return loss during heating underscores the importance of a well-designed microwave heating system.Abstract
Microwave heating provides a cleaner pyrometallurgical method for separating zinc from electric arc furnace dust (EAFD, a solid waste generated during steel production with excellent dielectric properties). Despite its undisputed heating efficiency, the impact of microwave heating characteristics on the zinc removal process from EAFD remains unclear. This paper focuses on ZnO, one of the primary components of EAFD, and develops an electromagnetic-thermal-chemical reaction model to analyze the effects of microwave power and graphite addition on heating behavior, reduction reactions, field distributions, and reaction kinetics. The results indicate that the heat generated from the interaction between microwaves and materials exhibits inherent non-uniformity, leading to the localized thermal effect and making the error of general temperature measurement methods. Increasing microwave power and adding graphite enhance heating efficiency and promote the reduction reaction but also result in significant internal-external temperature disparity and worse temperature distribution. At 1000 W, with 1.2 times the stoichiometric amount of graphite addition, the temperature measurement error reaches approximately 200 °C, potentially affecting the kinetic results to a certain degree. The non-isothermal kinetics results from simulations indicate that the localized thermal region exhibits a lower average activation energy of 47.5 kJ/mol compared to experimental results, suggesting that the lower activation energy of the ZnO reduction reaction during microwave heating is primarily caused by the localized thermal effect rather than the non-thermal effect. Additionally, in the energy distribution, the higher proportion of return loss during heating underscores the importance of a well-designed microwave heating system
Techno-economic analysis of biogas upgrading through amine scrubbing: A comparative study of different single amines
No full textAbstract
Bioenergy is gaining increasing prominence globally, highlighting the significant potential of biogas energy recovery for producing biomethane and capturing CO2 within the energy sector. Amine scrubbing stands out as a promising technology for achieving this goal by minimizing methane slippage and efficiently removing acid gases like CO2 and H2S. Despite extensive research on amine-based systems, a direct comparative analysis of various amines for biogas upgrading remains unexplored. This study provides a comprehensive evaluation of the techno-economic feasibility of biogas upgrading using five different amine solvents: monoethanolamine (MEA), diethanolamine (DEA), diisopropanolamine (DIPA), methyldiethanolamine (MDEA), and aminomethyl propanol (AMP). Simulations were conducted using Aspen Tech software to assess the performance of each system. The results show that to achieve a 91 % biomethane mass fraction, MEA, AMP, DIPA, DEA, and MDEA require 9, 11, 12, 13, and 25 stages, respectively. Additionally, the mass fraction of CO2 output from the stripper tower varies across the amines, with MEA, DIPA, DEA, MDEA, and AMP yielding values of 0.964, 0.938, 0.939, 0.933, and 0.999, respectively. From an economic perspective, total capital costs for implementing these systems are estimated at 110.72, 80.49, 66.57, 65.61, and 64.56 MUSD for MEA, MDEA, DIPA, DEA, and AMP, respectively. Operating profits of AMP, DEA, DIPA, MDEA, and MEA systems are projected at 18.55, 17.80, 17.62, 17.60, and 17.44 MUSD/year, respectively. The novelty of this work lies in the direct comparison of five distinct amine systems, providing a robust analysis of their performance, validation, and economic viability for biogas upgrading.Abstract
Bioenergy is gaining increasing prominence globally, highlighting the significant potential of biogas energy recovery for producing biomethane and capturing CO2 within the energy sector. Amine scrubbing stands out as a promising technology for achieving this goal by minimizing methane slippage and efficiently removing acid gases like CO2 and H2S. Despite extensive research on amine-based systems, a direct comparative analysis of various amines for biogas upgrading remains unexplored. This study provides a comprehensive evaluation of the techno-economic feasibility of biogas upgrading using five different amine solvents: monoethanolamine (MEA), diethanolamine (DEA), diisopropanolamine (DIPA), methyldiethanolamine (MDEA), and aminomethyl propanol (AMP). Simulations were conducted using Aspen Tech software to assess the performance of each system. The results show that to achieve a 91 % biomethane mass fraction, MEA, AMP, DIPA, DEA, and MDEA require 9, 11, 12, 13, and 25 stages, respectively. Additionally, the mass fraction of CO2 output from the stripper tower varies across the amines, with MEA, DIPA, DEA, MDEA, and AMP yielding values of 0.964, 0.938, 0.939, 0.933, and 0.999, respectively. From an economic perspective, total capital costs for implementing these systems are estimated at 110.72, 80.49, 66.57, 65.61, and 64.56 MUSD for MEA, MDEA, DIPA, DEA, and AMP, respectively. Operating profits of AMP, DEA, DIPA, MDEA, and MEA systems are projected at 18.55, 17.80, 17.62, 17.60, and 17.44 MUSD/year, respectively. The novelty of this work lies in the direct comparison of five distinct amine systems, providing a robust analysis of their performance, validation, and economic viability for biogas upgrading
'Schmidbaur gold chemistry' and beyond
Get PDFAbstract
Hubert Schmidbaur has significantly influenced the field of gold chemistry. His work on preparing various aurocyclic digold compounds and studying their structures and reactivities has laid the foundation for unique applications in photophysics and homogeneous catalysis. The naming and characterization, both experimental and theoretical, of the aurophilicity phenomenon have led to numerous interdisciplinary applications. The emergence and development of dynamic gold chemistry in the excited state, exemplify this impact. Preparative methodologies, characterization techniques, and qualitative bonding theories have been tested through the rational preparation of ligated, element-centred gold clusters. The potential of this fascinating class of compounds remains largely untapped.Abstract
Hubert Schmidbaur has significantly influenced the field of gold chemistry. His work on preparing various aurocyclic digold compounds and studying their structures and reactivities has laid the foundation for unique applications in photophysics and homogeneous catalysis. The naming and characterization, both experimental and theoretical, of the aurophilicity phenomenon have led to numerous interdisciplinary applications. The emergence and development of dynamic gold chemistry in the excited state, exemplify this impact. Preparative methodologies, characterization techniques, and qualitative bonding theories have been tested through the rational preparation of ligated, element-centred gold clusters. The potential of this fascinating class of compounds remains largely untapped
Barriers to blockchain adoption: Empirical observations from securities services value network
No full textAbstract
Blockchain can support the transition to a sustainable business by facilitating the traceability of activities that drives responsible behavior in a value delivery network. Despite its potential utility, the adoption rate is still relatively slow, and there are barriers to adopting this radical new technology. This research explores these barriers both from the organizational and business network perspectives. A qualitative study with interview data from financial service sector experts was conducted. In particular, informants represented securities services value network (SSVN). Using abductive reasoning, we found barriers that are further categorized into four dimensions: psychological-internal, functional-internal, psychological-external, and functional-external. For managers, this study offers new in-depth insights for facilitating new technology adoption, taking into account both company's internal and external viewpoints.Abstract
Blockchain can support the transition to a sustainable business by facilitating the traceability of activities that drives responsible behavior in a value delivery network. Despite its potential utility, the adoption rate is still relatively slow, and there are barriers to adopting this radical new technology. This research explores these barriers both from the organizational and business network perspectives. A qualitative study with interview data from financial service sector experts was conducted. In particular, informants represented securities services value network (SSVN). Using abductive reasoning, we found barriers that are further categorized into four dimensions: psychological-internal, functional-internal, psychological-external, and functional-external. For managers, this study offers new in-depth insights for facilitating new technology adoption, taking into account both company's internal and external viewpoints