bluuebunny/crossref_metadata_2025 huggingface dataset:
Comparing Numerical and Analytical Methods for Heat Loss Determination of District Heating Systems
Authors: Wieland Aaron , Weidlich Ingo , Dollhopf Stefan , Pourbozorgi Langroudi Pakdad
Published: May 2024

Energy efficiency assessment considers the heat losses in district heating systems. For instance, life cycle assessments of such engineering structures require knowledge of the heat losses during their use phase. Therefore, it is essential to have the most accurate knowledge of the heat losses of a district heating system. In this study, three different methods for the determination of specific heat losses for buried preinsulated steel pipes are compared. The first method involves an analytical calculation in accordance with EN 13941, while the second utilizes an equivalent circuit approach. The third method employs finite element analysis. The objective was to evaluate the accuracy of the methods, the achievable range of results, and the effort required to solve the respective calculation algorithms. Therefore, typical 2-dimensional cross sections including different pipe diameters were selected. In situ measurements were not part of this study. Consequently, the analysis centres on the deviation between the methods. All three methods determine the heat loss in both the supply and return pipes. While the analytical calculation method cannot determine temperatures in the soil, the equivalent circuit method can handle more complex tasks and gives detailed results at predefined points in the model. With the finite element method, a high degree of detail can be achieved, but the requirements for solving the algorithms increase. An emerging trend in district heating involves reducing operational temperatures in both new and existing networks. This will change the relation between heat losses and heat delivered to the customers. Subsequently, an increasing interest in the actual heat losses and the precision of calculation is expected within this development. Therefore, it remains essential to evaluate the performance of different models
Design and Performance Assessment of District Heating Systems in Latvian Region
Authors: Brumana Giovanni , Bazbauers Gatis , Rieksta Madara , Franchini Giuseppe , Ghirardi Elisa
Published: May 2024

The energy consumed by buildings for air conditioning accounts for a large percentage of global energy consumption. To promote efficiency and sustainability, the scientific community is making great efforts to develop renewable technologies. A well-known but unfortunately underestimated solution is the development of centralized heating and cooling systems that consistently reduce energy consumption.The work proposes a comparison between three heating configurations covering the demand of a settlement in the Latvian region: 1) centralized district heating (DH) system; 2) 5th generation district heating & cooling (5GDHC) system and 3) individual home heating (HH) systems. Thermal and electrical loads are evaluated by transient simulations of a residential area with 80 buildings for the Riga climate and compared with the same settlement in a Mediterranean region (Milan, IT). The energy plants are based on different technologies: combined heat and power (CHP) plants, gas-fired boilers, and domestic heat pumps.The analysis includes the option of power exchange with the national grid. A transient numerical model has been developed for each solution. Every component is modelled according to performance maps provided by the manufacturers, allowing an accurate simulation in both design and off-design operating conditions. The study includes energy, economic and environmental aspects.The result of the simulation highlights the large difference between the two locations, not only in terms of annual load, but also in terms of load distribution. On an annual basis, the Latvian residential complex requires almost twice as much energy as the Italian one. The thermal losses in the district systems are 4.21% in Milan solution and 5.65% in Riga. The district heating system coupled with heat pump represents the best layout in terms of primary energy consumption in both locations, with energy savings of 50% compared to other solutions. The use of 5GDHC is a good compromise that could increase the use of renewable energy. The adoption of cogeneration plant is a good choice in case of centralized district system that allows the installation of high efficiency genset. On the contrary, for small application as residential, the installation of cogeneration system results expensive and the conversion efficiency does not justify the installation.
Are BSR Municipalities on Track for Energy Transition?
Authors: Dolge Kristiāna , Vičmane Laura Kristiāna , Bohvalovs Ģirts , Blumberga Dagnija
Published: May 2024

Climate neutrality targets and the growing decentralization of energy systems have substantially increased the role of municipalities in global energy transition. However, global shifts and national government demands have often left local public authorities unprepared to face numerous challenges related to local space planning, cost-effective integration, and decarbonization of electricity, heating, industry, and mobility. Therefore, there is a need to investigate the current state of municipal energy transition and analyze how municipalities face climate neutrality target achievement. This study conducts an integrated energy sustainability assessment to investigate the progress of the energy transition in six municipalities in the Baltic Sea region. A benchmarking approach is applied to compare the different levels of energy efficiency and decarbonization in the municipalities. The study reveals different energy consumption patterns of municipal buildings, which are influenced by various factors such as the type of building (educational, office, social facilities, etc.), the heat source (district heating or individual local heat source) and the energy efficiency management practices applied. In addition, a different trend in the installation of renewable energy capacity can be observed in municipalities in Latvia, Lithuania, Poland and Sweden. The study analyses the overall gap between the production and consumption of renewable energy to determine the storage potential and the role in the local energy transitions. The findings of this study highlight the key cornerstones in the current state of municipal energy transition, setting a foundation for better and more effective energy policy planning at national and local scales.
Energy Efficiency Improvement for Manufacturing Companies in Latvia
Authors: Bantauska Evelina , Kubule Anna
Published: May 2024

Concerns about climate change and environmental issues are becoming more and more popular nowadays and are causing concerns in everyone's life and beyond. One of significant causes of climate change is energy consumption, especially in the manufacturing sector. Even though, energy efficiency (EE) topic has been extensively discussed, not all EE aims are met. For the manufacturing sector the reason is that EE is often not a top priority for the companies. Currently the companies are also faced with another big challenge – in this digital era of rapidly developing technologies they have to adjust their practices to seize the opportunities provided by digitalization and automatization. Therefore, the aim of this research is to explore how digitization can be combined with EE to promote the resilience and increase performance of manufacturing companies, and how remote data analysis, also by using machine learning tools, can help improve EE. Literature review, content analysis, empirical data analysis and cases studies from real production companies in Latvia are used to achieve the research goals. The results section shows how digital tools and real-time monitoring help assessing the current state of the business and make decisions on changes to future operations, helping to reduce consumption and the environmental impact of production. Manufacturing companies have the potential to improve EE through digitalisation, but the manufacturing processes are complex and Latvian companies are only slowly moving towards digitalisation. Therefore, there is a strong need to examine empirical cases to gather more perspective and to find a way to implement digitalization and EE improvement across all sectors. Conclusions suggest that manufacturing companies should be encouraged to move towards a more unified energy data collection system, enabling more efficient data analysis and proposals for energy efficiency improvements.
Air Flow Analysis for Triply Periodic Minimal Surface Heat Exchangers
Authors: Kancs Arturs
Published: May 2024

Due to the increasing popularity of additive manufacturing technologies, more varied and complex shapes of heat exchangers can be produced, that can be optimized to be more compact and efficient. In this paper a triply minimal periodic surface – gyroid structure is designed to study the applicability of such structures in air-to-air heat exchangers used in residential ventilation recuperation systems. Gyroid surface structures are useful to decrease overall heat exchanger size, pressure and increase heat transfer. Several geometry variations with different flow rate values were analysed to compare the efficiency of heat exchanger designs, as well as basic counterflow plate heat exchanger arrangement was analysed, to compare the gyroid designs to conventional methods. To calculate the pressure difference, temperature and heat transfer in each variation, SolidWorks Flow Simulation was used. The results showed that by using gyroid structures, heat exchanger energy transfer can be optimised for required back pressure and heat transfer, while reducing the overall dimensions, compared to conventional heat exchangers. By incorporating low cost, printed thermal recuperators, thermal efficiency of residential buildings can be improved. Suitable materials, manufacturing methods and application limitations are discussed.
Incorporating Life Cycle Assessment in the Green Metric Ranking: a Conceptual Approach
Authors: Palumbo Elisabetta , Romagnoli Francesco , Soust-Verdaguer Bernardette , Brumana Giovanni
Published: May 2024

Integrating sustainability principles into their daily operations is an overarching goal of universities and higher education institutions (HEIs), as knowledge multipliers, have to perform (Filimonau et al., 2021).Various studies have demonstrated that the operational activities of universities cause GWP emissions and, in general, negative environmental impacts, due mainly to student and staff mobility, on-campus energy and water consumption, and waste production (Jürgens et al., 2023). Findler et al. (2019) outlined numerous analytical methods, ranging from input-output analysis to full Life Cycle Assessment (LCA), for evaluating the carbon footprints of universities and colleges.Concurrently, a variety of tools have been devised to measure sustainability based on environmental metrics, such as the Green Metric (GM) ranking developed by Universitas Indonesia (UI). The GM, which is first in which tops university sustainability rankings (Marrone et al., 2018), rates HEIs by utilizing 51 criteria across 6 rating areas. Researchers analyzed the UI Green Metric World Ranking system to examine the requirements for a fair sustainability ranking of worldwide HEIs, although the latter were only examined in general without inspecting each item separately (Boiocchi et al., 2023).In order to lessen the environmental impacts of HEIs, recognized and robust methods must be used to identify appropriate and effective measures. LCA is a standardized (ISO 14040 and 14044) tool for quantifying and reducing environmental impacts throughout the entire life cycle of a product, service, or organization.This study is focused on understanding how LCA can be integrated into GM, and more specifically, how it can assist in achieving a consistent and structured review of specific indexes such as EC4, EC7, EC8, WR2, and TR1.The analysis was conducted by comparing the items one by one. Such a method was implemented as a results of the authors' specialized background, the scientific literature of interest, and the adoption of a critical thinking approach.The study results emphasize the necessity of incorporating LCA into the environmental sustainability strategies of HEIs. This integration is crucial for developing a robust approach adaptable to various local contexts, enhancing the precision in assessing and improving HEIs' sustainability practices. Such a strategy will align HEIs' operational activities more effectively with sustainable development goals. The application of the conceptual approach to a case study is recommended.
Will Changing Habits Ensure Sustainable Mobility: System Dynamics Modeling Examples from Municipalities in Four Countries
Authors: Safronova Alina , Barisa Aiga
Published: May 2024

The transportation industry stands out as a significant contributor to world emissions, which presents a significant obstacle to the process of decarbonization. This study recommends a comprehensive plan that addresses emissions not just on a national level but also on a local and individual level, with an emphasis on using a multi-dimensional approach. Our study aims to support municipalities in assessing and mitigating transportation-related emissions by using a system-dynamic approach and introducing a state-of-the-art instrument. In contrast to conventional assessments, which are primarily concerned with technical criteria, our approach takes into account the everyday routines of inhabitants as well as their willingness to accept sustainable policies.Dynamic modeling enhances our understanding of the intricate correlation between technical metrics and socio-behavioral dynamics. This allows us to provide municipalities with a strong basis for the creation of effective initiatives aimed at reducing emissions. This research adds to the subject of sustainable urban planning by promoting the increased public acceptance of sustainable mobility schemes and encouraging active public involvement. This analysis allows municipalities to build policies that not only target technical emissions but also integrate smoothly into the social framework of the local community. This is made possible by the fact that this study emphasizes the relevance of holistic and community-centered approaches. For municipalities that are attempting to navigate the complexities of emissions reduction in the transportation sector, it gives significant insights that highlight the requirement of policies that are both inclusive and adaptive to promote a sustainable urban future.
Life Cycle Analysis of a Battery Energy Storage System
Authors: Melnikova Baiba , Blumberga Dagnija
Published: May 2024

For Latvian government and transmission system operator energy security and independence has been an issue for a period of time, even more when political situation changed, motivating to act faster in order to swich off from BREL system completely. Therefore, three Baltic states have made an agreement on building more stable electricity transmission system within Baltic region and to connect with European transmission systems, building new stations with synchronous compensators and energy storage systems. In order to build a system, that allows to include more energy from renewable resources and secure possible disbalances in system, Latvian TSO operator is building a new battery energy storage system. This paper is aimed to look at what are the costs of this battery energy storage system from climate perspective to Latvia and its society in order to gain energy security and possibility to include more energy from renewable resources.
Creation of Single Cell Protein-Producing Mutants of Phaffia Rhodozyma
Authors: Saronova Jelizaveta , Raita Svetlana , Spalvins Kriss
Published: May 2024

Recently, there has been an increasing demand for sustainable protein sources for aquaculture. In aquaculture, sustainable protein includes sources that can be produced with a minimal environmental footprint, such as single-cell proteins, proteins from algae, insects, and by-products from the agricultural industry. Single-cell proteins that are derived from microorganisms show a sustainable alternative to traditional protein sources due to their high protein content and rapid growth. This research focuses on creating mutants of the yeast Phaffia rhodozyma to increase single-cell protein production. This yeast has significant industrial potential and biological features. The yeast Phaffia rhodozyma is already known for its unique ability to synthesize astaxanthin, so this case will focus on its ability to produce protein. In the study, we used wild strain yeast and previously obtained white mutants on inorganic nitrogen media for further random mutagenesis methods to introduce specific mutations into the genome aimed at improving their ability to biosynthesize protein. Amino acid inhibitor was used to select potential protein-producing mutants. The protein content of the biomass obtained from the experiments was analyzed in detail using BCA (Protein Assay Reagent) analysis, which confirmed their potential as a source of nutrients for aquaculture. This method is based on the reaction between bicinchoninic acid and the peptide bonds of proteins, which results in the formation of a color whose intensity is proportional to the amount of protein in the sample. The results obtained allow further research into the development of cost-effective and environmentally friendly alternatives for feed in aquaculture.
The Impact of RED III Directive on the Use of Renewable Fuels in Transport on the Example of Estonia
Authors: Ilves Risto , Allmägi Roland , Küüt Arne , Olt Jüri
Published: May 2024

Over the past two decades, there has been an increasing use of biofuels worldwide, especially in Europe. The main objective is to reduce greenhouse gas emissions, particularly carbon dioxide (CO2), from transportation. The regulation of fuels produced from biomass and other renewable sources at the EU level is primarily governed by the Renewable Energy Directive (RED). As of today, RED III directive has come into effect, significantly altering the EU fuel market by 2030. The main change involves an increase in the share of renewable fuels in transport and the non-use of first-generation fuels. Since all EU member states are obliged to comply with the RED III directive, it is essential to assess the current status of each member state in meeting the requirements for transport fuels. Therefore, the aim of this article is to analyze the impact of the RED III directive on the use of renewable fuels in the transport sector. Specifically, it provides an overview of various RED directives' requirements, analyzes the shares of renewable fuels in fossil diesel in Estonia under different RED III compliance scenarios, and presents an overview of the situation regarding the use of renewable fuels in Estonia. The article is based on a literature review, and fuel share calculations are based on RED III directive calculation methodologies. The results of the study indicate that if the requirement for the share of renewable energy used in transport is 29%, using only HVO (Hydrotreated Vegetable Oil) to achieve this goal would require replacing 30.3% of diesel with HVO. In cases where there is a requirement to reduce the greenhouse gas emission intensity of fuels in the transport sector by at least 14.5% by 2030, the volumetric share of HVO fuel must meet certain criteria based on the raw material. For example, fuel produced from residues must contain a minimal amount of biocomponents. In this context, biologically derived oil is initially used, such as in food preparation. Subsequently, after its use in food preparation, it is processed into fuel. The article also addresses cases where biogas is introduced as a renewable component in replacing diesel.
Analytic Hierarchy Process Assessment Framework for Blockchain in Renewable Energy
Authors: Kalniņa Anete , Romagnoli Francesco , Feofilovs Maksims , Mazūre Gunita
Published: May 2024

The urgency to reach net-zero emissions until 2050 has created a vast interest in innovative technologies for renewable energy sector. At the same time the need for trusty and unfailing solutions will rise considering the increasing amount of decentralized and decarbonized energy systems. It has previously been described in the literature that the aforementioned characteristics could be combined by blockchain technology. Therefore, this study focuses on the practical side – the opinion of industry experts about the use of blockchain technology in renewable energy. By using analytic hierarchy process analysis, the goal of this study is to develop a methodology for the selection of the most appropriate blockchain applications in renewable energy and to identify and evaluate the possible types of use taking into account socio-economic, political and legal, technological and environmental factors. The results of this study highlights the important influence of political, legal and technological factors like involvement of government institutions and possible attacks to the system, but considers the economic factors as the least significant for the introduction and use of blockchain technology in the renewable energy sector. The most promising use cases for blockchain would be associated with reliable and immutable certificates of origin for renewable energy and use in smart grid (including smart metering), smart homes and relevant Internet of Things applications. The use of crypto-assets and initial coin offerings for renewable energy development should be viewed with precaution and willingness to inform and educate considering social factors like public opinion and societies’ knowledge on crypto-assets.
Unveiling Future Offshore Wind Potential: A Multi-Criteria Framework for Sustainable Development
Authors: Nagababu Garlapati , Basak Deepjyothi , Puppala Harish , Patel Jaydeep
Published: May 2024

Climate change poses a critical threat to the environment and human societies, prompting a shift towards clean energy sources. Among these sources, offshore wind energy emerged as a promising alternative, due to its consistent and strong wind resource availability, coupled with matured technology. However, offshore wind energy being susceptible to the climate change, the efficiency, reliability, and financial viability of the offshore wind farms is location specific. Therefore, the present study introduces a novel framework for identifying suitable regions for offshore wind farm development by considering future projections under the various Shared Socioeconomic Pathway (SSP) scenarios. A weighted multi-model ensemble (MMEwt) created using nine Coupled Model Intercomparison Project Phase 6 (CMIP6) climate models was considered for the analysis. The suitability of a location is evaluated considering richness, stability of the resource, risk, and economic factors. CRiteria Importance Through Intercriteria Correlation (CRITIC) multi-criteria technique is used to evaluate the prominence of each factor Technique for Order Preference by Similarity to Ideal Solution (TOPSIS) technique is used to determine the suitability of each grid within the study area and their hierarchy. Findings of this study showed that the north-western and southern regions within the study area are relatively plausible compared to other regions. The proposed methodology built on the theoretical framework of multi-criteria techniques can be extended to other regions and determine the suitability map of plausible wind regions over the specified area for future time periods.
A Novel GE-Mackinsey Market Approach: Investment Opportunity for the Biopolymer Packaging Materials
Authors: Patel Nidhiben , Blumberga Dagnija
Published: May 2024

Sustainable development in agriculture seeks to implement a robust bioeconomy strategy by valorizing agricultural resources into value-added products. Compared to primary biomass use, using agriculture residues and wastes can achieve higher reductions in GHG emissions and lower feedstock costs. Bioeconomy has substantial potential for high-value products such as biopolymers, pharmaceuticals, and food and feed additives. Low-value applications like bioenergy, biofuels, and bulk chemicals have a weak potential for bioeconomy development. However, high value-added products, including biopolymers, require an equal focus as other products in the bioeconomy value pyramid that can lift the market to elevate sustainable bioeconomy development. A successful transition through radical innovations must be justifiable, with economic, environmental, and social benefits primarily promoted by stakeholders, businesses, or government organizations. One of the core options would be to know the market potential of the biopolymer products. Here, a methodology for decision-making to evaluate four existing biopolymer packaging materials (Cellulose, PHA, PLA, and starch) in the EU market has been developed using the GE-McKinsey Nine-Box Matrix, considering market attractiveness and product competitive advantage. Market innovations can be fostered by integrating the resource availability and technology advancement indicators to the methodology steps. The methodology considers sustainability advantages for the agriculture sector and promotes the strategic commercialization of biopolymer packaging materials. Product-specific indicators are used to evaluate the market attractiveness and product competitive advantage. The research findings show that PLA biopolymer packaging material has the highest potential for commercialization. The application of this methodology and its results provide a justifiable way of determining the investments in value-added products and allow investors to make the right decision-making choice for bioplastic packaging materials, ensuring their sustainability and profitability in the market.
Impact of EU Funding on Latvian Aquaculture: Productivity, Competitiveness and Perspectives
Authors: Laktuka Krista , Lauka Dace
Published: May 2024

The eligibility period for the 2014-2020 Operational Programme of the EU's European Maritime and Fisheries Fund (EMFF) closed at the end of 2023. The allocation under the EMFF to the Latvian fisheries and aquaculture sector was more than €130 million, distributed in accordance with Latvia's Fisheries Development Action Programme 2014-2020. The primary objective of this research is to analyse the outcomes attained through the allocation of funding and ascertain the extent to which Latvian aquaculture productivity has augmented, alongside its competitive standing and sustainability across both domestic and global markets. This includes integrating technological advances and innovative practices into existing aquaculture companies, as well as providing funding for projects that stimulate the creation of new aquaculture companies, such as the promotion of community-led local development strategies and the collection and availability of sector-specific data that could indirectly contribute to the development of the sector. A cost-effectiveness analysis was conducted to ascertain the anticipated return on the EU funding provided and evaluate the amplified growth prospects within the aquaculture sector. The results show that the performance indicators and targets set for the aquaculture sector as part of the funding allocation are vague and consequently do not lead to a recognisable increase in aquaculture productivity or added value.
Use of the National Climate and Energy Policy Simulation Tool in the Policy Making Process
Authors: Zvirbule Karina , Liberova Veronika , Blumberga Andra
Published: May 2024

Energy transition towards CO2 neutral energy systems is challenging as the national energy policy depends on numerous factors. In system dynamics approach these factors are identified as causal and feedback loops with lock-ins, as a result constituting stock-and-flow structure. Such a kind of structure is used in different simulation tools. This study analyses the use of the Latvian national climate and energy policy simulation tool in the policy making process. As a hypothesis of the study was set that the simulation tool, which is based on the principles of systemic thinking (explaining causal relationships) and an easy-to-use user interface, significantly improves the national energy and climate policy making process. Accordingly, to verify the hypothesis the task was to evaluate the use of the national climate and energy policy simulation tool in the policy-making process. For the evaluation the relevant literature was reviewed: climate and energy policy goals, policies and legislation in the European Union and Latvia; approaches to modeling national climate and energy policies, including optimization models, simulation models; the use of simulation models in the modeling of national climate and energy policies; the use of system dynamics models in the modeling of national climate and energy policies. Besides using the systemic thinking approach in the process of creating national climate and energy policies, the user experience in building simulation tools was used. Based on the literature analysis, improvements to the interface of the national climate and energy simulation tool developed by Riga Technical University, Institute of Energy Systems and Environment were made and developed training material for the use of the simulation tool, based on explaining the causal relationships built into the model.
Optimizing the Battery Management Algorithm of the Agricultural Robot Based on the Workload
Authors: Pihlap Heino , Lillerand Tormi , Olt Jüri
Published: May 2024

This article focuses on optimizing the battery management algorithm  to minimize the amount of  energy remaining in the battery at the end of the workload.The increasing use of renewable energy to operate agricultural robots increases the autonomy of the robot's energy supply. The volatility of renewable energy in turn increases the need for a smart battery management system.  In the case of non-optimized battery management, up to 25% of the energy in the battery may remain unused, depending on the workload. A battery management algorithm was developed, which allows reducing the amount of residual energy remaining in the battery depending on the workload and increasing the time utilization factor of the agricultural robot. The concept was proven with computer models that use data of the energy consumption of the farming robot and the limitations of the workload due to the geometry of the cultivated fields.
Sustainable End-of-Life Tyre Management: A Comprehensive Analysis of Environmental Impacts and Crumb Rubber Integration in Composite Concretes
Authors: Kolendo Girts , Bumanis Girts , Korjakins Aleksandrs , Bajare Diana
Published: May 2024

The research explores pollution prevention strategies associated with end-of-life tyres (ELTs) through sustainable practices, focusing on repurposing ELTs into crumb rubber (CR) for use in composite concretes for civil engineering applications. Three disposal approaches are considered: recycling into crumb rubber for use in cement composites to enhance acoustic properties, incineration for cement production, and landfill disposal. The study aims to assess the environmental impact of each method, particularly in terms of carbon dioxide (CO2) emissions during the recycling phase, utilizing the OpenLCA program for a comprehensive life cycle analysis. The primary objective is to provide insights into the sustainability of incorporating recycled rubber in concrete mixes as fine aggregate to improve concrete acoustic and shock absorbance properties. The research also gathers data on CO2 emissions from ELT incineration for cement production and the environmental implications of ELT’s landfill disposal. By comparing these three strategies, the study offers a holistic perspective on the environmental ramifications of ELT management. Notably, a recent study highlights the energy recovery and CO2 emissions from ELT incineration, demonstrating the potential benefits of recycling. The research identifies a gap in existing studies, emphasizing the need to consider the entire life cycle, including the transportation and use stages. Notably, the use stage significantly contributes to environmental impacts, with carbon emissions ranging from 550 to 840 kg CO2 eq., per car tyre. Additionally, a proposed inventory analysis method evaluates greenhouse gas emissions from Portland cement concrete pavement construction, revealing that raw material production accounts for most emissions. The findings of this research are providing valuable insights for policymakers, industry professionals, and environmentalists aiming for sustainable practices in the construction sector. By allocating a fraction of tyre production CO2 emissions to obtain raw material for concrete composites, the study suggests a potential avenue for reducing environmental impact. Further calculations using the OpenLCA program may refine these recommendations.
End-Of-Life Management of Photovoltaic Panels: A Model for Forecasting and Economic Evaluation
Authors: Franzoni Andrea , Leggerini Chiara , Bannò Mariasole
Published: May 2024

The global surge in photovoltaic (PV) panel deployment since the 2000s has contributed to advancing the renewable energy sector. However, this proliferation raises concerns about the increasing number of PV modules that will end their operational life in the coming years, necessitating effective planning for their decommissioning and recovery. This paper addresses this imminent challenge by presenting a predictive model to estimate the volume of decommissioned modules from existing installations. To take into account the variability associated with the operational life duration of PV panels, three distinct scenarios were considered: early loss, regular loss (both modelled through the Weibull function) and fixed loss. Furthermore, the article introduces a methodology for the economic valorisation of materials recovered from decommissioned PV modules, according to the different technologies employed. This approach encourages sustainable practices by assigning an economic value to recovered materials, promoting a circular economy in the renewable energy sector. The economic valuation methodology adds practicality to dismantling, emphasising responsible waste management's potential economic benefits. In order to illustrate the applicability of the model, the study focuses on the Italian case, providing a detailed regional breakdown. The regional analysis not only improves the accuracy of the predictive model but also offers insights into localised PV module disposal patterns. By adapting the model to the individual Italian regions, the article serves as a concrete and valuable resource during the programming and planning phases, facilitating the implementation of a strategy to efficiently recover PV modules and consequently minimising the environmental impact associated with decommissioning activities.
Stearate from Steel Wire Drawing Processes as a Resource
Authors: Collina Elena , Antonini Carlo , Capitani Giancarlo , Cosentino Ugo , Lasagni Marina , Mezzanotte Valeria
Published: May 2024

STAR (Stearato dai processi di Trafilatura del filo di Acciaio come Risorsa) project, funded by the Italian Ministry of the Environment, has the ambition of redesigning the use and life cycle of waste stearates from the steel wire drawing industry, promoting the circular life of such materials. Waste stearate is having a strong impact on the economic and environmental sustainability of the steel wire production processes, adding up to the increasing pressure that industry has been facing in the last years: the pandemic crisis, the raw material price increase, the commercial restrictions related to the Ukraine and other regional conflicts.The short-term goal of the project is to develop a technology to be applied on a local scale and the long-term one is expanding it internationally. The benefits are both environmental, due to the reduction of waste and related impact on the environment, and economic, due to stearate valorization.First, stearate waste from wire drawing process were characterized in order to valorize them in the production of new materials or as an energy source.Samples of stearate waste were provided by wire drawing industries and the analyses showed that the humidity content was always low (0.1 – 5 %), while the volatile solids (VS) content varied from 2 to 70%, covering a very wide range and thus indicating a variable organic matter content. The mean higher heating value was 26 MJ/kg and the Chemical Oxygen Demand (COD) 500 mg O2/g and correlated well with VS. pH was strongly basic (>11).Anaerobic digestion can surely have an important role in valorization, as it allows to recover energy and to produce a stabilized digestate for which a further use can be studied, according to its properties. Preliminary BMP tests (BMP = Biomethane Potential) determined a biomethane production in the range 500-900 L/kgVS, much higher than the production from animal waste (around 400 L/kgVS). The toxicity of the digestate was assessed by Microtox® assay and was negligible. This finding supports the hypothesis that recalcitrant compounds, which do not undergo degradation in anaerobic conditions, are not toxic.
An important role for triglyceride in regulating spermatogenesis
Authors: Chao Charlotte F , Pesch Yanina-Yasmin , Yu Huaxu , Wang Chenjingyi , Aristizabal Maria J , Huan Tao , Tanentzapf Guy , Rideout Elizabeth
Published: May 2024

Drosophila is a powerful model to study how lipids affect spermatogenesis. Yet, the contribution of neutral lipids, a major lipid group which resides in organelles called lipid droplets (LD), to sperm development is largely unknown. Emerging evidence suggests LD are present in the testis and that loss of neutral lipid- and LD-associated genes causes subfertility; however, key regulators of testis neutral lipids and LD remain unclear. Here, we show LD are present in early-stage somatic and germline cells within the Drosophila testis. We identified a role for triglyceride lipase brummer (bmm) in regulating testis LD, and found that whole-body loss of bmm leads to defects in sperm development. Importantly, these represent cell-autonomous roles for bmm in regulating testis LD and spermatogenesis. Because lipidomic analysis of bmm mutants revealed excess triglyceride accumulation, and spermatogenic defects in bmm mutants were rescued by genetically blocking triglyceride synthesis, our data suggest that bmm-mediated regulation of triglyceride influences sperm development. This identifies triglyceride as an important neutral lipid that contributes to Drosophila sperm development, and reveals a key role for bmm in regulating testis triglyceride levels during spermatogenesis.
Chromosomal instability induced in cancer can enhance macrophage-initiated immune responses that include anti-tumor IgG
Authors: Hayes Brandon H , Wang Mai , Zhu Hui , Phan Steven H , Dooling Lawrence J , Andrechak Jason C , Chang Alexander H , Tobin Michael P , Ontko Nicholas M , Marchena Tristan , Discher Dennis E
Published: May 2024

Solid tumors generally exhibit chromosome copy number variation, which is typically caused by chromosomal instability (CIN) in mitosis. The resulting aneuploidy can drive evolution and associates with poor prognosis in various cancer types as well as poor response to T-cell checkpoint blockade in melanoma. Macrophages and the SIRPα-CD47 checkpoint are understudied in such contexts. Here, CIN is induced in poorly immunogenic B16F10 mouse melanoma cells using spindle assembly checkpoint MPS1 inhibitors that generate persistent micronuclei and diverse aneuploidy while skewing macrophages toward a tumoricidal ‘M1-like’ phenotype based on markers and short-term anti-tumor studies. Mice bearing CIN-afflicted tumors with wild-type CD47 levels succumb similar to controls, but long-term survival is maximized by SIRPα blockade on adoptively transferred myeloid cells plus anti-tumor monoclonal IgG. Such cells are the initiating effector cells, and survivors make de novo anti-cancer IgG that not only promote phagocytosis of CD47-null cells but also suppress tumor growth. CIN does not affect the IgG response, but pairing CIN with maximal macrophage anti-cancer activity increases durable cures that possess a vaccination-like response against recurrence.
ESAT-6 undergoes self-association at phagosomal pH and an ESAT-6-specific nanobody restricts M. tuberculosis growth in macrophages
Authors: Bates Timothy A , Trank-Greene Mila , Nguyenla Xammy , Anastas Aidan , Gurmessa Sintayehu K , Merutka Ilaria R , Dixon Shandee D , Shumate Anthony , Groncki Abigail R , Parson Matthew AH , Ingram Jessica R , Barklis Eric , Burke John E , Shinde Ujwal , Ploegh Hidde L , Tafesse Fikadu G
Published: May 2024

Mycobacterium tuberculosis (Mtb) is known to survive within macrophages by compromising the integrity of the phagosomal compartment in which it resides. This activity primarily relies on the ESX-1 secretion system, predominantly involving the protein duo ESAT-6 and CFP-10. CFP-10 likely acts as a chaperone, while ESAT-6 likely disrupts phagosomal membrane stability via a largely unknown mechanism. we employ a series of biochemical analyses, protein modeling techniques, and a novel ESAT-6-specific nanobody to gain insight into the ESAT-6’s mode of action. First, we measure the binding kinetics of the tight 1:1 complex formed by ESAT-6 and CFP-10 at neutral pH. Subsequently, we demonstrate a rapid self-association of ESAT-6 into large complexes under acidic conditions, leading to the identification of a stable tetrameric ESAT-6 species. Using molecular dynamics simulations, we pinpoint the most probable interaction interface. Furthermore, we show that cytoplasmic expression of an anti-ESAT-6 nanobody blocks Mtb replication, thereby underlining the pivotal role of ESAT-6 in intracellular survival. Together, these data suggest that ESAT-6 acts by a pH-dependent mechanism to establish two-way communication between the cytoplasm and the Mtb-containing phagosome.
Single-cell transcriptome reveals the heterogeneity of malignant ductal cells and the prognostic value of REG4 and SPINK1 in primary pancreatic ductal adenocarcinoma
Authors: Ji Yutian , Xu Qianhui , Wang Weilin
Published: May 2024

Background

Pancreatic ductal adenocarcinoma (PDAC) is one of the leading causes of cancer-related deaths, with very limited therapeutic options available. This study aims to comprehensively depict the heterogeneity and identify prognostic targets for PDAC with single-cell RNA sequencing (scRNA-seq) analysis.

Methods

ScRNA-seq analysis was performed on 16 primary PDAC and three adjacent lesions. A series of analytical methods were applied for analysis in cell clustering, gene profiling, lineage trajectory analysis and cell-to-cell interactions. In vitro experiments including colony formation, wound healing and sphere formation assay were performed to assess the role of makers.

Results

A total of 32,480 cells were clustered into six major populations, among which the ductal cell cluster expressing high copy number variants (CNVs) was defined as malignant cells. Malignant cells were further subtyped into five subgroups which exhibited specific features in immunologic and metabolic activities. Pseudotime trajectory analysis indicated that components of various oncogenic pathways were differentially expressed along tumor progression. Furthermore, intensive substantial crosstalk between ductal cells and stromal cells was identified. Finally, genes (REG4 and SPINK1) screened out of differentially expressed genes (DEGs) were upregulated in PDAC cell lines. Silencing either of them significantly impaired proliferation, invasion, migration and stemness of PDAC cells.

Conclusions

Our findings offer a valuable resource for deciphering the heterogeneity of malignant ductal cells in PDAC. REG4 and SPINK1 are expected to be promising targets for PDAC therapy.
Linking patient-reported oral and general health-related quality of life
Authors: Paulson Danna R. , Chanthavisouk Phonsuda , John Mike T. , Feuerstahler Leah , Chen Xing , Ingleshwar Aparna
Published: May 2024

Background

The relationship between oral and overall health is of interest to health care professionals and patients alike. This study investigated the correlation between oral health-related quality of life (OHRQoL) and health-related quality of life (HRQoL) in a general adult population.

Methods

This cross-sectional study used a convenience sample of adult participants (N = 607) attending the 2022 Minnesota County and State fairs in USA, the 5-item Oral Health Impact Profile (OHIP-5) assessed OHRQoL, and the 10-item PROMIS v.1.2 Global Health Instrument assessed HRQoL. Spearman and Pearson correlations were used to summarize the bivariable relationship between OHRQoL and HRQoL (both physical and mental health dimensions). A structural equation model determined OHRQoL-HRQoL correlations (r). Correlations’ magnitude was interpreted according to Cohen’s guidelines (r = 0.10, 0.30, and 0.50 to demarcate “small,” “medium,” and “large” effects, respectively).

Results

OHRQoL and HRQoL correlated with r = 0.52 (95% confidence interval, CI: [0.50–0.55]), indicating that the two constructs shared 27% of their information. According to Cohen, this was a “large” effect. OHRQoL, and the physical and mental HRQoL dimensions correlated with r = 0.55 (95% CI: [0.50–0.59]) and r = 0.43 (95% CI: [0.40–0.46]), respectively, indicating a “large” and a “medium” effect. OHRQoL and HRQoL were substantially correlated in an adult population.

Conclusion

Using OHIP-5 to assess their dental patients’ oral health impact allows dental professionals to gain insights into patients’ overall health-related wellbeing.
Epigallocatechin gallate protects MC3T3-E1 cells from cadmium-induced apoptosis and dysfunction via modulating PI3K/AKT/mTOR and Nrf2/HO-1 pathways
Authors: Wei Fanhao , Lin Kai , Ruan Binjia , Wang Chaoyong , Yang Lixun , Wang Hongwei , Wang Yongxiang
Published: May 2024

Epigallocatechin gallate (EGCG), an active constituent of tea, is recognized for its anticancer and anti-inflammatory properties. However, the specific mechanism by which EGCG protects osteoblasts from cadmium-induced damage remains incompletely understood. Here, the action of EGCG was investigated by exposing MC3T3-E1 osteoblasts to EGCG and CdCl2 and examining their growth, apoptosis, and differentiation. It was found that EGCG promoted the viability of cadmium-exposed MC3T3-E1 cells, mitigated apoptosis, and promoted both maturation and mineralization. Additionally, CdCl2 has been reported to inhibit both the phosphoinositide 3-kinase/protein kinase B/mammalian target of rapamycin (PI3K/AKT/mTOR) and nuclear factor erythroid 2-related factor 2/heme oxygenase-1(Nrf2/HO-1) signaling pathways. EGCG treatment attenuated cadmium-induced apoptosis in osteoblasts and restored their function by upregulating both signaling pathways. The findings provide compelling evidence for EGCG’s role in attenuating cadmium-induced osteoblast apoptosis and dysfunction through activating the PI3K/AKT/mTOR and Nrf2/HO-1 pathways. This suggests the potential of using EGCG for treating cadmium-induced osteoblast dysfunction.