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Rapid and scalable detection of synthetic mRNA byproducts using polynucleotide phosphorylase and polythymidine oligonucleotides
Get PDFProduction and storage of synthetic mRNA can introduce a variety of byproducts which reduce the overall integrity and functionality of mRNA vaccines and therapeutics. mRNA integrity is therefore designated as a critical quality attribute which must be evaluated with state-of-the-art analytical methods before clinical use. The current study first demonstrates the effect of heat degradation on transcript translatability and then describes a novel enzymatic approach to assess the integrity of conventional mRNA and long self-amplifying mRNA. By first hybridizing oligo-T to the poly(A) tail of intact mRNA and subsequently digesting the unhybridized RNA fragments with a 3’-5’ exoribonuclease, individual nucleotides can be selectively released from RNA fragments. The adenosine-based fraction of these nucleotides can then be converted into ATP and detected by luminescence as a sensitive indicator of mRNA byproducts. We developed a polynucleotide phosphorylase (PNPase)-based assay that offers fast and sensitive evaluation of mRNA integrity, regardless of its length, thus presenting a novel and fully scalable alternative to chromatographic-, electrophoresis-, or sequencing-based techniques.publishedVersio
Basic design of an ORC demonstrator system for implementation in an Iron & Steel plant through the DECAGONE project
Get PDFWaste heat recovery (WHR) technologies offer great opportunities for improving energy efficiency and reducing CO2 emissions for energy intensive industrial processes. The DECAGONE project is developing an innovative ORC-based WHR system to be demonstrated in an iron & steel plant located in the Czech Republic. The design of the ORC system considers the practical site-specific conditions and limitations, such as variations in heat source conditions, heat sink availability, and size and space limitations for the ORC components. Various cycle configurations are compared with a thermodynamic optimization model for maximizing the net power output subject to the process constraints, including (1) recuperative vs. non-recuperative designs, (2) air vs. water as heat sink and (3) direct vs. indirect evaporation. The recuperative cycle with indirect evaporation and direct air condensation is deemed the most suitable solution for the project site conditions. The results provide recommendations for performance improvement and indications for performance subject to practical plant operating conditions, such as large range of temperature and flow rate of waste heat source. Analyses in this work provide the basis for detailed component design and decision processes towards finalizing the design of the demonstrator.Basic design of an ORC demonstrator system for implementation in an Iron & Steel plant through the DECAGONE projectpublishedVersio
Laboratory method for investigating the influence of industrial process conditions on the emission of polycyclic aromatic hydrocarbons from carbonaceous materials
Get PDFThis work is dedicated to developing a laboratory method for assessing emissions of polycyclic aromatic hydrocarbons (PAHs) from different carbon-based materials at elevated temperatures. The method will additionally contribute to enhancing the fundamental knowledge about the formation and decomposition of these compounds during various process conditions. Developing a method entails designing a setup for laboratory-scale experiments utilizing different furnace configurations and off-gas capturing media. To demonstrate the method's applicability, different carbon materials were tested under identical conditions, and analysis results for the same material in different furnace setups were compared. In this article, we have focused on the procedure for obtaining the “fingerprint” of PAH emissions under conditions characteristic of industrial processes.
• Two setups for investigation of the influence of temperature on PAH emissions were designed and tested for three types of carbon materials.
• The collected off-gas samples underwent analysis in two different laboratories to capture intra-laboratory differences and to evaluate the significance of the instrument detection limit.
• The results of PAH 16 (16 EPA PAH) and PAH 42 analysis were compared to showcase the influence of the expanded list on the overall emission of PAH.
The novel methodology enables the determination and comparison of PAH emissions during the thermal treatment of individual carbon materials under laboratory conditions. This could potentially be a new approach for predicting the PAH emissions in metallurgical industries that use these carbon materials as reducing agents in their processes and their control by optimizing process parameters and raw materials used. In addition to being suitable for simulating various conditions in the metallurgical industry, the utilization of low-hazard PAH solvents makes it a promising method.publishedVersio
Revisiting the response of microstructure and performance to cold pre-strain and the early aging stage in Al–Zn–Mg–Cu alloy
Get PDFIn recent years, extensive research on dynamic precipitation has led to a growing interest in exploring how deformation affects microstructure and mechanical properties. In this study, the response of microstructure and performance to cold pre-strain and the early aging stage in the Al–Zn–Mg–Cu alloy was investigated using a combination of modelling and experimental approaches. A Kampmann-Wagner based numerical framework was developed and applied to the Al–Zn–Mg–Cu alloy. The deformation or quenching induced dislocations and vacancies, their dynamics and acceleration on the diffusivities of solute atoms, and the competition between homogeneous and heterogeneous nucleation were considered in the framework. The effect of the different pre-strain levels (0%–10%) on the evolution of vacancies, dislocations, precipitation kinetics and hardening are given in detail. The results suggest that the acceleration of precipitation kinetics and hardening during the aging process following pre-strain is primarily attributed to the overall increase in diffusivity resulting from deformation-induced dislocations, rather than vacancies. The simulation framework developed in the current work effectively captures the evolution of microstructure and mechanical properties, which has significant practical implications for materials manufacturing.publishedVersio
Fleet repositioning in the tramp ship routing and scheduling problem with bunker optimization: A matheuristic solution approach
Get PDFThis paper investigates an important planning problem faced by dry bulk shipping operators, referred to as the Tramp Ship Routing and Scheduling Problem with Bunker Optimization (TSRSPBO). The problem is to maximize the overall profit of a fleet of vessels by selecting cargoes and determining ship routes and schedules. We consider this problem under a set of practically relevant features such as flexibility in cargo quantities, as well as bunkering decisions on where to procure fuel and how much. As a particularly novel feature, we address the regional allocation of vessels at the end of the planning period to be well prepared for meeting (uncertain) future demand. To incorporate this, we consider the TSRSPBO as a two-stage stochastic programming problem, where cargo selection, routing, and bunkering decisions are solved in the first-stage problem, and the recourse cost of fleet repositioning is considered in the second stage. We present arc flow and path flow formulations, where the latter employs a priori generation of feasible routes as input. For solving realistically sized instances, we propose a matheuristic based on an Adaptive Large Neighborhood Search (ALNS) framework that iteratively generates columns and solves the path flow model. Computational experiments based on real data show that this matheuristic finds high-quality solutions for large test instances with 120 cargoes, 30 vessels, and ten bunker ports in less than one hour. Also, considering the TSRSPBO as a two-stage stochastic problem achieves the highest profits and is solved almost as quickly as the deterministic problem variant.publishedVersio
Potential for surplus-heat-to-power conversion in current and future aluminium production process with off-gas recycling
Get PDFIncreased utilization of industrial surplus heat can make significant contributions towards reaching energy efficiency and emissions reduction goals. The off-gas from metal production smelters can contain large amounts of thermal energy, and conversion to electric power often appears an enticing prospect. However, the practical potential for exploitation can be significantly reduced from plant processes that are designed considering surplus heat as a waste product to get rid of. This typically makes the heat accessible only at reduced temperatures. The HighEFF research centre for industrial energy efficiency has studied technologies, applications, and cases for surplus heat utilization since its start in 2016. Heat-to-power conversion has been explored in several cases provided by the partner industries from – among others – Norwegian aluminium manufacturers. Centre research activities also include novel production processes and modifications, which has side effects providing very different conditions and constraints for energy recovery. One such process modification is off-gas recirculation, mainly developed to increase concentration of CO2 in the off-gas to improve conditions for CO2 capture in the future, but which also will alter off-gas temperature and recoverable heat as a side effect. This could improve the potential for energy recovery. In this work, the potential for energy recovery is evaluated and compared in four cases – one representing a current aluminium process, and three future process scenarios with flue gas recycling. The simulated heat-to-power conversion is done by applying an organic Rankine cycle (ORC) optimization model to each case. The results indicate significant benefits to energy recovery in the recycling cases. In the case with the highest recycling rate and flue gas temperature, the potential for electric power production increases by 270 % compared to the present-day case. In addition, the reduced work of the main exhaust fans in the recycling cases brings further energy savings on the system level equivalent to 25–50 % of the ORC power output, further increasing overall energy efficiency. From this, some potential synergies between process design, heat-to-power, and thermal integration of other technologies such as CO2-capture are discussedPotential for surplus-heat-to-power conversion in current and future aluminium production process with off-gas recyclingpublishedVersio
Georeferenced X (formerly twitter) data as a proxy of mobility behaviour: case study of Norway
Get PDFGeoreferenced messages on social media represent a powerful data source to gain a different perspective for estimating mobility behaviour, which is still mainly based on travel surveys. These data are openly available, yet few studies have explored their potential. This paper assesses the feasibility of large-scale Twitter data as a proxy of human mobility behaviour to complement traditional travel surveys, and for calibration and validation of transport models. Almost 12 million Tweets from more than 90,000 users were further analysed to detect the trip patterns at municipality level in Norway from 2012 to 2022. Results showed that the mobility patterns changed between 2014 and 2019 for the travel survey, as for 2019 most of the reported trips were short and concentrated in the densely populated areas of the country, where most respondents lived, triggering a lack of information for certain areas. In contrast, Twitter data presented a more stable data source along both years with similar population distribution and average trip length. Although Twitter data have limitations in relation to the socio-demographic information of the users, it could complement the travel survey given the broader spatial and temporal distribution of this large-scale data.publishedVersio
Nanoenabled Immunomodulatory Scaffolds for Cartilage Tissue Engineering
Get PDFArticular cartilage regeneration is a challenge in tissue engineering. Although diverse materials have been developed for this purpose, cartilage regeneration remains suboptimal. The integration of nanomaterials into 3D network materials holds great potential in the improvement of key mechanical properties, particularly important for osteochondral replacement scaffolds and even to function as carriers for disease-modifying drugs or other regulatory signals. In this study, a simple yet effective cell-free nanoenabled Col-PLA scaffold specially designed to enhance cartilage regeneration and modulate inflammatory response is proposed, by incorporating poly(lactic-co-glycolic acid) (PLGA) ibuprofen nanoparticles (NPs) into a collagen/polylactide (Col-PLA) matrix. The developed nanoenabled scaffold successfully decreases IL-1β release and leads to primary human chondrocytes survival, ultimately restoring extracellular matrix (ECM) production under inflammatory conditions. The nanoenabled Col-PLA scaffolds secretome effectively decreases macrophage invasion in vitro, as well as neutrophil infiltration and inflammatory mediators’, namely the complement component C5/C5a, C-reactive protein, IL-1β, MMP9, CCL20, and CXCL1/KC production in vivo in a rodent air-pouch model. Overall, the established nanoenabled scaffold has the potential to support chondrogenesis as well as modulate inflammatory response, overcoming the limitations of traditional tissue engineering strategies.publishedVersio
Corrosion Investigation by Scanning Electrochemical Microscopy of AISI 446 and Ti-Coated AISI 446 Ferritic Stainless Steel as Potential Material for Bipolar Plate in PEMWE
Get PDFThe components of proton exchange membrane water electrolysers frequently experience corrosion issues, especially at high anodic polarization, that restrict the use of more affordable alternatives to titanium. Here, we investigate localized corrosion processes of bare and Ti-coated AISI 446 ferritic stainless steel under anodic polarization by scanning electrochemical microscopy (SECM) in sodium sulphate and potassium chloride solutions. SECM approach curves and area scans measured at open-circuit potential (OCP) of the samples in the feedback mode using a redox mediator evidence a negative feedback effect caused by the surface passive film. For the anodic polarization of the sample, the substrate generation-tip collection mode enables to observe local generation of iron (II) ions, as well as formation of molecular oxygen. For the uncoated AISI 446 sample, localized corrosion is detected in sodium sulphate solution simultaneously with oxygen formation at anodic potentials of 1.0 V vs. Ag/AgCl, whereas significant pitting corrosion is observed even at 0.2 V vs. Ag/AgCl in potassium chloride solution. The Ti-coated AISI 446 sample reveals enhanced corrosion resistance in both test solutions, without any evidence of iron (II) ions generation at anodic potentials of 1.2 V vs. Ag/AgCl, where only oxygen formation is observed.publishedVersio
Development of a test method for adhesive tapes certification and application
No full textSufficient airtightness of a building envelope is important both to ensure the overall energy efficiency of a building and to prevent moisture-related damage to the structure. Air leakages typically occur in the context of joints and perforations in vapor barriers installed inside walls and roofs. It is essential to give proper attention to details to achieve sufficient airtightness of building envelopes and joint’s durability. Sealing such building details with durable solutions is essential for ensuring sufficient airtightness overall. In recent years, adhesive tapes have increasingly been used for this application. However, there remains uncertainty regarding its performance in the long-term. The study offers an overview of the current state of the art by incorporating findings from a literature review including an analysis of established methods currently being used for evaluation of tape joint durability, as well as other experimental test methods. The aim of research presented in this paper is to contribute to the development of a test method with sufficient accuracy, reproducibility, and repeatability to be used in the development and certification of tape products and systems. Although the method in development displays limitations in terms of reproducibility, it is regarded as a promising concept. Through further development, the method is believed to be suitable for potential integration into wider evaluation programs addressing adhesive tape durability, supplementary to existing methods.publishedVersio