RISE – Research Institutes of Sweden
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Analysis of soft tissue integration-supportive cell functions in gingival fibroblasts cultured on 3D printed biomaterials for oral implant-supported prostheses
No full textTo date, it is unknown whether 3D printed fixed oral implant-supported prostheses can achieve comparable soft tissue integration (STI) to clinically established subtractively manufactured counterparts. STI is mediated among others by gingival fibroblasts (GFs) and is modulated by biomaterial surface characteristics. Therefore, the aim of the present work was to investigate the GF response of a 3D printed methacrylate photopolymer and a hybrid ceramic-filled methacrylate photopolymer for fixed implant-supported prostheses in the sense of supporting an STI. Subtractively manufactured samples made from methacrylate polymer and hybrid ceramic were evaluated for comparison and samples from yttria-stabilized tetragonal zirconia polycrystal (3Y-TZP), comprising well documented biocompatibility, served as control. Surface topography was analyzed by scanning electron microscopy and interferometry, elemental composition by energy-dispersive x-ray spectroscopy, and wettability by contact angle measurement. The response of GFs obtained from five donors was examined in terms of membrane integrity, adhesion, morphogenesis, metabolic activity, and proliferation behavior by a lactate-dehydrogenase assay, fluorescent staining, a resazurin-based assay, and DNA quantification. The results revealed all surfaces were smooth and hydrophilic. GF adhesion, metabolic activity and proliferation were impaired by 3D printed biomaterials compared to subtractively manufactured comparison surfaces and the 3Y-TZP control, whereas membrane integrity was comparable. Within the limits of the present investigation, it was concluded that subtractively manufactured surfaces are superior compared to 3D printed surfaces to support STI. For the development of biologically optimized 3D printable biomaterials, consecutive studies will focus on the improvement of cytocompatibility and the synthesis of STI-relevant extracellular matrix constituents.This work was funded by Progress in Science and Education with Ceramics (PROSEC, grant number PRG‐2022‐03005) and the Berta‐Ottenstein‐Program for Advanced Clinician Scientists, Faculty of Medicine, University of Freiburg.</p
Critical Factors to Consider When Designing an Innovation Management System
No full textOrganizations can implement an innovation management system in order to address the multidimensional challenges they often have in their practical innovation work. Until the ISO 56002 standard was released in 2019, there was no international standard for the design of innovation management systems. The standard provides support as a framework and highlights important systems elements. We studied two early adopters that have used this international standard to design their innovation management systems. Based on the study findings, we devised a practical approach for framing the design of an innovation management system. The approach includes a set of steps and critical considerations that include understanding a company's innovation ambitions and direction, analyzing the systemic dimensions of the system (the elements and how they interconnect), and introducing a balanced set of control mechanisms
Polymerization of benzoxazine impregnated in porous carbons. A scalable and low-cost route to smart copper-ion absorbents with saturation indicator function
No full textPorous carbon materials are common materials used for sensor and absorbent applications. A novel approach for functionalizing porous carbons through the impregnation of porous carbon black with benzoxazine monomers, followed by thermal polymerization is introduced herein. The method not only establishes a new avenue for the functionalization of porous carbons but also endows the resulting material with both copper ion-binding and sensing properties. We showcase the versatility of the technique by illustrating that the polymerization of phenols with benzoxazine monomers serves as an extra tool to customize absorption- and sensing properties. Experimental validation involved testing the method on carbon black as a porous substrate, which was impregnated with both bisphenol-a benzoxazine and a combination of bisphenol-a benzoxazine and alizarin. The resulting materials were assessed for their dual functionality as both an absorbent and a sensor for copper ions by varied copper ion concentrations and exposure times. The dye absorption test demonstrated a notable capacity to accumulate copper ions from dilute solutions. Electrochemical characterization further confirmed the effectiveness of the modified carbons, as electrodes produced from inks were successful in detecting copper ions accumulated from 50 μM Cu2+ solutions. With this work, we aspire to set the steppingstone towards a facile functionalization of porous carbon materials towards water purification applications. © 2024 The AuthorsThis project is completely funded by The Swedish Foundation for Strategic Environmental Research (Mistra), project name MISTRA TerraClean (project no. 2015/31).</p
Visit Experience and Fulfillment of Care Needs in Primary Care Differs for Video Visits Compared to In-person and Chat Visits
No full textBackground: There is a lack of research comparing patient experience and to what extent patients’ care needs are fulfilled in telemedicine compared to in-person care. Objective: To investigate if patient experience and fulfillment of care needs differ between video and chat visits with direct to consumer telemedicine providers compared to in-person visits. Design: Cross-sectional study. Participants: Adults visiting a primary care physician in person or via chat or video in Region Stockholm, Sweden, October 2020–May 2021. Main Measures: Patient-reported visit experience and fulfillment of care needs. Key Results: The sample included 3315 patients who had an in-person (1950), video (844), or chat (521) visit. Response rates were 42% for in-person visitors and 41% for telemedicine visitors. Patients were 18–97 years old, mean age of 51 years, and 66% were female. In-person visitors reported the most positive patient experience (“To a very high degree” or “Yes, completely”) for being listened to (64%), being treated with care (64%), and feeling trust and confidence in the health care professional (76%). Chat visitors reported the most positive patient experience for being given enough time (61%) and having care needs fulfilled during the care visit (76%). Video visitors had the largest proportion of respondents choosing “To a very low degree” or “No, not at all” for all visit experience measures. There were statistically significant differences in the distribution of visit experiences between in-person, video, and chat visits for all visit experience measures (P < 0.001). Conclusions: Video visits were associated with a more negative visit experience and lower fulfillment of care needs than in-person visits. Chat visits were associated with a similar patient experience and fulfillment of care needs as in-person visits. Chat visits may be a viable alternative to in-person visits for selected patients.Open access funding provided by Karolinska Institute. This study was funded by the Swedish Research Council (2021\u2013006426) and Region Stockholm (2018\u20131076). The study was also financed by grants from Region Stockholm, clinical research appointment (YTL), and from AFA F\u00F6rs\u00E4kring (190210) (MH, IM). </p
Manufacturing of thermoplastic composite sandwich panels using induction welding under vacuum
No full textA new method to manufacture thermoplastic composite sandwich panels is presented, making use of the induction welding process in which a magnetic susceptor generates the heat at the core/facesheet interface. This technique proposes a fast way to assemble thermoplastic sandwich structures without risking the deconsolidation of the composites skin. The welding pressure is obtained by applying vacuum over the sandwich panel. This vacuum induction welding method (Vac-IW) allows joining thermoplastic composite facesheets to a thermoplastic polymer core in a clean and non-contact manner. The feasibility of the method is demonstrated by preparing sandwich samples made of glass fibre reinforced polyetheretherketone (PEEK) skins and a 3D-printed polyetherimide (PEI) honeycomb core. A susceptor made of PEI and µm-sized nickel (Ni) particles is used to generate heat by magnetic hysteresis losses. The strength of the sandwich samples assembled by the Vac-IW method is evaluated by flatwise tensile (FWT) tests. The authors acknowledge financial support from CREPEC (Research Center for High Performance Polymer and Composite Systems), NSERC (Natural Sciences and Engineering Research Council of Canada) (grant number ALLRP 556497-20), PRIMA Qu\u00E9bec (P\u00F4le de Recherche et d'Innovation en Mat\u00E9riaux Avanc\u00E9s) (grant number R20-13-004), the Canadian Space Agency (CSA), Ariane Group, NanoXplore inc, Mekanik and Dyze Design.</p
BRAVENT – Storskala branntester (del 1): Brannytelse for ikke-brannklassifiserte ventilasjonskomponenter
No full textBRAVENT – Large-scale fire tests (part 1): Fire performance for non-fire rated ventilation components In the overall BRAVENT project, the goal is to generate answers and documentation on current issues related to ventilation and fire by examining these with experimental fire tests. The present study aimed to evaluate the fire performance of key non-fire-rated components, mainly DCV dampers and exhaust filters, in a comfort ventilation system by testing the hypothesis that the ventilation components will not be damaged by fire within 30 or 60 minutes. To test the hypothesis, a total of 14 large-scale fire tests with different fuels were carried out. The tests were carried out in a test building with several rooms that are representative of classrooms, offices, and corridors. The fire tests were designed to investigate relevant fire scenarios for school buildings, but the findings from the tests can also be used for other purpose-built buildings. The building was equipped with a full-fledged damper-optimized ventilation system, sized to serve a total of 450 m2 and thus provide a realistic basis for the fire tests. Currently, there is no documentation on how non-fire-rated dampers are affected by high temperatures that occur during a fire. The temperature specifications given for non-fire rated DCV dampers are intended for normal operation. Two different types of DCV dampers were tested. In one type, the airflow was measured with a measuring cross, and for the other, the airflow was measured with sensors integrated into the damper blade itself. In several of the conducted tests the non-fire-rated dampers were not able to sustain their function for the required duration of 30 minutes or longer, and failed completely when the temperature inside or outside the dampers reached about 200 ºC. Misreporting of some temperature measurements in the building management system already occurred at lower temperatures, around 120˚C, without significantly affecting the delivered air flow rate. For the damper type with a measuring cross, the plastic hoses connecting the measuring cross and the measuring transducer for the damper melted when hot smoke was transported through the damper. This failure resulted in the DCV damper measuring too low or no airflow. In several tests, this measurement error meant that the DCV damper opened fully, trying to achieve a large enough airflow. In one of the tests where the supply air damper was placed inside the fire room, such a fault on the supply air damper caused it to close completely. In addition to the damage to the dampers, the power supply to the damper was destroyed, and a fuse for the power supply in the control cabinet was short-circuited. This resulted in the building management system losing contact with all the dampers. This shows that a local error can cause the entire system to fail. For the other damper type, where the sensors were located in the damper blade, the high temperatures caused the entire damper blade to melt. It was not observed that soot in the fire smoke led to problems with the dampers' measuring sensors for any of the damper types examined. This indicates that for the performed test series, high temperature and not soot was the greatest challenge for the dampers in the event of a fire. In addition to examining how dampers are affected by fire, there was also an investigation into how the filter performs during a fire. It was found that the filter could largely capture the soot particles in the smoke. This means that equipment located downstream of the filter is relatively well protected against soot, and the possibility of soot contamination to the supply air side via a rotating heat recovery unit can, therefore, be considered minimal as long as the filter is not damaged. However, when the filter collects so much soot, it shows that the potential for the filter to clog. How quickly this happens depends, among other things, on the materials that burn and the size of the fire in relation to the air handling unit's capacity. This also aligns with results from an earlier BRAVENT project [1]. The air temperature in the unit was in all tests carried out below 60˚C and thus lower than the filters' maximum operating temperature of 70˚C. The conclusion from the tests is that the extraction principle with non-fire-rated components cannot be considered a safe strategy for 30 or 60 minutes.Finansiert av: Norges forskningsråd, program SAMRISK-2-Samfunnssikkerhet og risiko, prosjektnummer 321099 og prosjektpartnerne</p
Survey of bidirectional transmittance distribution function measurement facilities by multilateral scale comparisons
No full textIn recent years, a growing demand for the capability of performing accurate measurements of the bidirectional transmittance distribution function (BTDF) has been observed in industry, research and development, and aerospace applications. However, there exists no calibration and measurement capabilities-entry for BTDF in the database of the Bureau International des Poids et Mesures and to date no BTDF comparison has been conducted between different national metrology institutes (NMIs) or designated institutes (DIs). As a first step to a possible future key comparison and to test the existing capabilities of determining this measurand, two interlaboratory comparisons were performed. In comparison one, five samples of three different types of optical transmissive diffusers were measured by five NMIs and one DI. By specific sample choice, the focus for this study lay more on orientation-dependent scatter properties. In comparison two, where one NMI, one DI, one university, and three industrial partners investigated their measurement capabilities, the dependence on the orientation was not assessed, but two additional samples of the same material and different thickness were measured. Results of the two comparisons are presented, giving a good overview of existing experimental solutions, and showing specific sample-related problems to be solved for improved future BTDF measurements.This work has been done in the frame of the EMPIR Project18SIB03 (BxDiff) that has received funding from the EMPIRprogramme co-financed by the Participating States and fromthe European Union’s Horizon 2020 research and innovationprogramme.This publication is part of the Project TED2021-129661B-C21, funded by the MCIN/AEI/10.13039/501100011033 andby the European Union ‘NextGenerationEU’/PRTR</p
A methodological framework for assessing sustainability aspects of fruit and vegetables
No full textCurrent European policies and the growing focus on sustainability show a clear need for defining and measuring aspects of sustainability at the food product level. The aim of this study was to develop an indicator-based framework to monitor the sustainability of fruits and vegetables. The framework includes production, packaging, transport, and distribution, and considers economic, ecological, and social aspects. The framework aims to be used by the food production and distribution sector and is intended to use specific data from the value chain for higher relevance for the food industry. Results of a sustainability assessment of carrots are presented, as the first example of application of the framework. Future research should focus on the framework’s validity when applied to other products and other countries.This work was supported by BAMA AS [2020] and the project GreenRoad financed by the Norwegian Research Council [Grant nr 320810 ].</p
Bonding strength between spruce glulam and birch plywood at different load-to-plywood face grain angles
No full textThere is growing interest recently in reducing the usage of metals in timber structures. Birch plywood possesses satisfactory mechanical properties compared to other wood-based panels and is promising to be utilized in timber connections as a substitute for the more conventional slotted-in metal plate. There are essentially two possibilities to connect plywood plates and other timber elements by means of either mechanical connections or adhesively bonded connections. Despite the more commonly adopted mechanical connections in current timber structures, the adhesively bonded connections hold the distinct advantages of being more cost-effective, stiffer, and with a lower risk of moisture penetration in the timber elements. When employing birch plywood in timber structure applications such as trusses and frame corners, stresses from different directions need to be transmitted by the plywood gusset plate. However, it is still uncertain how the bonding strength is affected by different loading angles to the face grain. This research question, specifically concerning the bonding strength between birch plywood and spruce glulam, has been addressed in this paper. It was found that the bonding strength varies within a relatively small range when the load-to-plywood face grain angle varies from 0° to 90°, which is promising for the development of adhesively bonded joints. Failure mainly occurred in glulam at 0° and 15°; while at other angles, a mixture of cohesive failure in glulam and plywood face veneer was dominant. The weak angle-dependence of the bonding strength can be explained by further checking the shear strength of the weaker wood adherends between glulam and plywood. A strong positive correlation was observed between bonding strength and the wood shear strength. The authors wish to gratefully acknowledge China Scholarship Council, Svenskt Trä, Vinnova project 2017-02712 “Outdoor load-bearing timber structures” within the BioInnovation program and Vinnova project 2021-03681 “Rational building systems for medium to long-span timber structures” within the strategic innovation program for Production2030 for the financial support. Koskisen is thanked for supplying the birch plywood materials and Moelven is acknowledged for supplying the glulam materials.</p
Public Procurement and Geofencing – lessons learned from a pilot with geofencing of service trips
No full textThe city of Gothenburg public procured geofencing technology and did a pilot during fall 2022 with geofenced service trips vehicles (retrofitted). This report investigates the challenges and opportunities associated with procuring geofencing technology, addressing aspects such as needs, market analysis, risk, alternative solutions, legislative framework, and much more based on lessons learned from the pilot. Geofencing, defined as the creation of virtual boundaries to monitor, inform, and control traffic using electronic communication technologies or predefined boundaries within vehicles, lacks standardization and comprises various technical solutions. Its functionality depends on digital mapping, vehicle tracking methods like GNSS, onboard equipment, real-time connectivity, and additional databases for traffic rules. Geofencing offers degrees of control, from informing and alerting drivers about speed limits to actively restricting vehicle speed, with possibilities for static, dynamic, and smart adaptations. Applications range from enhancing traffic safety by alerting drivers and controlling vehicle speed to improving transport efficiency through optimized route selection and environmental benefits by reducing emissions and noise pollution. However, regulatory challenges persist, such as the absence of type-approved geofencing equipment and the need to define functional requirements rather than specific technologies in legal frameworks, presenting both opportunities and obstacles for its implementation in road traffic management and procurement processes. The first step in public procurement involves laying the groundwork by comprehensively understanding the buying organization's needs and market capabilities to meet them. The city identified key goals such as safe travel and driver assistance. The city explored existing agreements and engaged operators for a geofencing pilot to address speed compliance and traffic safety concerns, alongside researching market options and risks associated with third-party equipment installation and data privacy. Alternatives like ISA and ADAS were considered but deemed insufficient. In the second step the procurement is carried out, which includes tasks such as producing procurement documents, advertising, evaluating tenders, and ultimately selecting a supplier. The city procured the geofencing technology by direct public procurement and used a traditional public procurement to get hold of vehicles and drivers. In the third step of the public procurement implementation is in focus on, executing the pilot and evaluating its outcomes, particularly concerning geofencing technology. Challenges arose during implementation, including difficulties in accurately mapping zones to individual vehicles due to problems with the speed box installed. The city of Gothenburg learned valuable lessons, highlighting the importance of direct communication with drivers, verifying technology before widespread adoption, and close collaboration between all stakeholders. Despite challenges, the pilot provided valuable data and insights, with recommendations offered for future geofencing initiatives, emphasizing early supplier dialogue, thorough testing, user experience understanding, and involving relevant stakeholders from the outset. In this report insights, advice and lessons learned are also shared. Technical hurdles include the lack of standardized geofencing, difficulty in retrofitting diverse vehicle fleets, and limited market availability. Organizational challenges encompass the need for a needs-driven approach, internal and external collaboration, and balancing technology with user acceptance. Concerns about data privacy and driver behaviour emerge, requiring careful navigation of GDPR regulations. Strategically deciding the city's role in IT-solutions, data collection, and responsibility for vehicle behaviour poses business-related challenges. The report concludes that while geofencing technology isn't yet ready for full-scale implementation, further pilots are necessary for development. Future work involves exploring alternative solutions, enhancing internal processes, and conducting larger pilots to advance understanding and implementation of geofencing technology