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Furfural:Enhancing production via boronate esters
Get PDFAs a way of combatting climate change, biomass can be used as an alternative to fossil resources. A promising route is through the platform chemical furfural, a molecule that can not only be easily created from biomass (i.e. the C5-sugars that make up most of the hemicellulose, predominantly xylose) but can also be transformed into a wide array of other molecules. Current processes for producing furfural have a molecular selectivity of 50 % from sugar to furfural and a large energy requirement, which needs to be addressed before furfural can be used as a keystone in the energy transition.One of the ways to improve the furfural yield is via the boronate route. In this route, xylose first reacts with a boronic acid to produce a boronate ester. As the sugar is hydrophilic but the ester hydrophobic, this allows for the sugar to be extracted from a (dilute) aqueous stream. The second step of the process is hydrolyzing the ester back to xylose and subsequently dehydrating it in an acidic aqueous medium to form furfural. As the equilibrium for both sugar/ester and furfural is towards the organic phase, their concentration in the aqueous phase is low. This suppresses the amount of byproduct formed, improving the yield of furfural.In this thesis, the viability of the boronate route is researched. By both performing the first and second step of the process in practice and modelling it, a final design of a 50 ktpa furfural plant can be made, allowing for the determination of the (economic) viability of the process. Various aspects of the process are investigated, such as the choice of chemicals and reaction conditions in both steps of the process. Most data is obtained with a model solution of pure xylose in water, but some experiments are replicated with acid hydrolysate of sugarcane bagasse, validating that the process will deliver similar results when actual biomass is used
Automated cardiac arrest detection and emergency service alerting using device-independent smartwatch technology:proof-of-principle
Get PDFIntroduction: Out-of-hospital cardiac arrest (OHCA) is a leading cause of mortality. Automated detection could improve survival by reducing delays in first responder activation. This study provides proof-of-principle for a device-independent technology that can (A) distinguish presence versus absence of spontaneous circulation, and (B) reliably alert emergency medical services (EMS). Methods: Circulatory arrest data were collected from three groups: (1) volunteers undergoing temporarily restricted blood flow to the arm using a cuff, (2) patients undergoing cardioplegic cardiac arrest for heart surgery, and (3) domestic swine, slaughtered in food industry. Data were collected using Samsung Watch5 and Watch5 Pro. An algorithm was developed to analyze photoplethysmography signals and detect circulatory arrest. Emergency response was tested via the Dutch community first responder network HartslagNu, using their test environment to activate test responders and EMS. Results: Nineteen participants were analyzed. Across all three groups, 28 of 31 circulatory arrests were correctly identified, sensitivity 90.3% (95% CI: 74.2%–98.0%), and hour-level specificity was 94.1% (95% CI: 71.3%–99.9%). Triggering a circulatory arrest consistently resulted in an audiovisual smartwatch alarm and an instantaneous alert to the virtual EMS at the HartslagNu test server. Conclusion: This study demonstrates the feasibility of detecting circulatory arrest using commercially available smartwatch sensors, achieving high sensitivity and specificity. Additionally, we integrated an automated alerting system with emergency networks to notify first responders. While this technology shows promise to improve survival, higher specificity is needed to prevent overburdening EMS. Future research should focus on real-world validation using actual cardiac arrest data.</p
Review on properties, physics, and fabrication of two-dimensional material-based metal-matrix composites (2DMMCs) for heat transfer systems
Get PDFIn the exploration of new materials development, 2D materials have received much attention due to their outstanding properties in terms of e.g. strength, and electrical and thermal conductivities. Graphene and boron nitride, amongst other 2D materials, are renowned for their exceptional thermal conductivity. In this review, we examine the properties, physics, and fabrication techniques of 2D material-based metal-matrix composites (2DMMCs) with a specific focus on heat transfer systems. The on-going demand for better electronic cooling systems in combination with advancements in mass production techniques of 2D materials facilitates the application of 2DMMCs in heat transfer systems. However, currently, the thermal behaviour of 2DMMCs remains largely uncategorized, strengthening the timely context of this review. Next to recent research progress, material properties, production techniques and strategies for improving thermal conductivity of 2DMMCs are addressed in this work. Methods to reliably assess the thermal conductivity of 2D enhanced materials are discussed alongside the fabrication techniques for 2D-material feedstocks for 2DMMCs production. Also, current limitations in the heat transfer capabilities of 2DMMCs, alongside prospects for enhancing thermal properties through emerging technologies, such as additive manufacturing, are addressed.</p
Experiences with Take it Personal!+ from People with Mild Intellectual Disability or Borderline Intellectual Functioning and Substance Use Disorder and Their Confidants:A Qualitative Study
Get PDFIntroduction: Take it Personal!+ is a treatment program for individuals with Mild Intellectual Disability or Borderline Intellectual Functioning (MID-BIF) and Substance Use Disorder (SUD). It is supported by a mobile health application (mHealth), and researchers found it can reduce Substance Use (SU). Aims: This study aimed to explore the usability of the treatment program in as experienced by clients and their confidants. Methods: We conducted post-treatment, semi-structured interviews with clients (n = 8) and their confidants (n = 8). We coded transcripts according to thematic analysis and using inductive and deductive methods. Subsequently, we analyzed connections between the codes and grouped them into themes using axial coding. Results: Overall clients and confidants experienced the treatment program as usable, and most mentioned the program helped to reduce SU. The clients and confidants reported the presence of a confidant was helpful. Some clients and confidants reported the mHealth application was helpful. Components that were perceived as effective were self-control skills, daily registration exercise and discussing quantity of SU non-judgingly. Perceived impeding factors were video calling and a non-supportive network. Conclusion: This study shows that Take it Personal!+ is an useable treatment program for individuals with MID-BIF and SUD, that helps to decrease their self-reported SU. Nevertheless, there is room for improvement for further adapting the treatment, which will be discussed.</p
Business model innovation in a research ecosystem:the case of rare diseases
No full textPurpose: Complex systems in scientific research require special efforts to develop and evolve in a sustainable way. Business model innovation has become highly relevant to overcome threats to the sustainability of such systems, and understanding it is key to maintaining and creating new value for the community. The European Joint Programme on Rare Diseases sought to create an effective rare disease research ecosystem for the benefit of patients. The aim of this study is to identify the factors that could influence business model innovation in this environment and to assess the overall potential of the ecosystem. Design/methodology/approach: A from Strengths, Weaknesses, Opportunities and Threats (SWOT/TOWS) analysis was carried out to identify these dimensions in the rare disease research ecosystem and the relationships between them. To support the analysis, the authors reviewed the literature to conceptualise business model innovation, particularly in the life sciences research area. Findings: Actions on marketing strategies, a customer-centric mindset and a sound legal basis for data sharing and access while accelerating the creation of expert groups and branding are among the key steps to ensure the sustainable viability of such an ecosystem. Originality/value: The findings provide a framework for adapting business models to the dynamics of the rare diseases research field. Innovation, supported by the community’s trust in the human capital that has worked for years to build this environment, is key to its sustainability.</p
Understanding the Light-Driven Enhancement of CO<sub>2</sub> Hydrogenation over Ru/TiO<sub>2</sub> Catalysts
Get PDFRu/TiO2 catalysts are well known for their high activity in the hydrogenation of CO2 to CH4 (the Sabatier reaction). This activity is commonly attributed to strong metal–support interactions (SMSIs), associated with reducible oxide layers partly covering the Ru-metal particles. Moreover, isothermal rates of formation of CH4 can be significantly enhanced by the exposure of Ru/TiO2 to light of UV/visible wavelengths, even at relatively low intensities. In this study, we confirm the significant enhancement in the rate of formation of methane in the conversion of CO2, e.g., at 200 °C from ~1.2 mol gRu−1·h−1 to ~1.8 mol gRu−1·h−1 by UV/Vis illumination of a hydrogen-treated Ru/TiOx catalyst. The activation energy does not change upon illumination—the rate enhancement coincides with a temperature increase of approximately 10 °C in steady state (flow) conditions. In-situ DRIFT experiments, performed in batch mode, demonstrate that the Ru–CO absorption frequency is shifted and the intensity reduced by combined UV/Vis illumination in the temperature range of 200–350 °C, which is more significant than can be explained by temperature enhancement alone. Moreover, exposing the catalyst to either UV (predominantly exciting TiO2) or visible illumination (exclusively exciting Ru) at small intensities leads to very similar effects on Ru–CO IR intensities, formed in situ by exposure to CO2. This further confirms that the temperature increase is likely not the only explanation for the enhancement in the reaction rates. Rather, as corroborated by photophysical studies reported in the literature, we propose that illumination induces changes in the electron density of Ru partly covered by a thin layer of TiOx, lowering the CO coverage, and thus enhancing the methane formation rate upon illumination.</p
Joint effect of aquaculture and land reclamation on sediment dynamics
No full textStudy region: Sansha Bay, ChinaStudy focus: The rapid development of global coastal aquaculture and land reclamation are significantly changing the offshore sediment dynamics system. Based on remote sensing, in-situ observation, digital elevation models and numerical simulation, the research surveyed and simulated changes in aquaculture and land reclamation areas, their effects on sediment dynamics, and the resulting bed erosion/deposition in Sansha Bay from 2005 to 2020. New hydrological insights for the region:From 2005–2020, aquaculture and land reclamation areas increased from 6.2 km2 and 16.5 km2 to 154 km2 and 55.3 km2, respectively. In the subtidal area, the sharp increase in aquaculture area dominated the changes in sediment dynamics, altering the vertical velocity profile from a logarithmic to bow shape due to double boundary effect of top aquaculture and bottom bed. This effect shifted maximum velocity layer downward to 0.4–0.6H and the average bottom velocity increased by 10 %, the bottom suspended sediment concentration (SSC) increased 26 %, resulting in a 102 % increase in bed erosion. While in intertidal flat, increased land reclamation dominated the changes in sediment dynamics and weakened the hydrodynamics due to dam reflection effect. This effect decreased bottom velocity by 15 % and SSC by 22 %, resulting in a 153 % increase in bed deposition. This study provides a reference case for the impact of offshore aquaculture and land reclamation on sediment dynamics
Being Sorry is the Hardest Thing:How Robots can Apologize and Learn from Mistakes to Restore People’s Trust
No full textRobots that move around people in the workplace will make mistakes, such as getting too close to someone or blocking the way. These mistakes negatively impact people’s experience with and attitudes toward robots. For a robot to successfully recover from mistakes during navigation, we need deeper insights into the effects of these mistakes and the effectiveness of different recovery strategies. We conducted an online survey (N=219) to assess people’s trust in a robot before and after errors, using three recovery strategies (communicating learning capability, apologizing, or a combination of both). Results show that trust dropped significantly after a navigational error but could be effectively restored, especially when the robot apologizes and communicates its ability to learn from it. When the robot does not try to recover from a mistake, the effects are very detrimental. These results highlight the importance of appropriate error recovery strategies for robots to enhance human-robot interactions.</p
Enhancing Observability:Real-Time Application Health Checks
Get PDFLog management and application health monitoring practices are cumbersome and often still require significant human intervention to prevent inaccurate data and information. Existing technologies like Elasticsearch and Grafana offer opportunities to automate and improve these practices. This paper reports on a design solution aimed at enhancing log categorization, anomaly detection, and real-time application health reporting for CAPE Groep’s service application. The proposed solution leverages Elasticsearch’s Machine Learning capabilities and Grafana’s dynamic visualization tools, alongside a newly developed dashboard named Horus, to centralize log data and automate monitoring processes. Preliminary results indicate that the proposed solution significantly improves the accuracy and timeliness of health reports, reduces manual intervention, and provides comprehensive real-time insights into application performance. This paper outlines the requirements, architectural design, and phased implementation plan, demonstrating the potential to streamline operations, enhance service delivery, and support future more stringent scalability requirements.</p
WATCHDOG:an ontology-aWare risk AssessmenT approaCH via object-oriented DisruptiOn Graphs
No full textWhen considering risky events or actions, we must not downplay the role of involved objects: a charged battery in our phone averts the risk of being stranded in the desert after a flat tyre, and a functional firewall mitigates the risk of a hacker intruding the network. The Common Ontology of Value and Risk (COVER) highlights how the role of objects and their relationships remains pivotal to performing transparent, complete and accountable risk assessment. In this paper, we operationalize some of the notions proposed by COVER – such as parthood between objects and participation of objects in events/actions – by presenting a new framework for risk assessment: WATCHDOG. WATCHDOG enriches the expressivity of vetted formal models for risk – i.e., fault trees and attack trees – by bridging the disciplines of ontology and formal methods into an ontology-aware formal framework composed by a more expressive modelling formalism, Object-Oriented Disruption Graphs (DOGs), logic (DOGLog) and an intermediate query language (DOGLang). With these, WATCHDOG allows risk assessors to pose questions about disruption propagation, disruption likelihood and risk levels, keeping the fundamental role of objects at risk always in sight.</p