Search Results (6,652)

Medical cannabis cultivation requires substantial energy for heating, lighting, and climate control. This study evaluates the economic feasibility of an innovative biomass-fired micro-CHP system in a greenhouse facility for medicinal cannabis cultivation. The system comprises an 80 kW_th boiler retrofitted for biomass and a 7 kW_el ORC engine and is assessed against a diesel-boiler Business-As-Usual (BAU) benchmark. Thermal load simulations for two growing periods (1 March–30 June and 1 September–30 December) estimate an annual heating demand of 91,065.20 kWh_th. The micro-CHP system delivers 8195.87 kWh_el per year, exceeding the greenhouse’s 7839.90 kWh_el consumption. Over a 30-year lifespan at a 7% discount rate, Life Cycle Costing yields EUR 196,421.33 for micro-CHP versus EUR 229,468.46 for BAU, a 14.4% reduction. Under all-equity financing, the project achieves an NPV of EUR 59,591.88, IRR of 27.32%, and a DPBP of 12.1 years; with 70% debt financing, NPV rises to EUR 61,211.39 and DPBP shortens to 10.5 years. Levelized Cost of Energy (LCOE) and Heat (LCOH) are EUR 0.122 per kWh_el and EUR 0.062 per kWh_th, respectively. While the LCOE is below the Greek and EU non-household averages (EUR 0.1578 and EUR 0.1515 per kWh_el), the LCOH exceeds the corresponding heat price benchmarks (EUR 0.0401 and EUR 0.0535 per kWh_th). These results indicate that, in the modeled context, biomass-ORC cogeneration can be a financially attractive and lower-carbon option for medicinal cannabis greenhouse operations. Full article

Between 51% and 72% of a bituminous roofing membrane used for structural waterproofing consists of organic material, predominantly bitumen—a derivative of crude oil refining—highlighting the strong dependence of this product on fossil resources. Considering that several tonnes of these membranes must be replaced every 30 to 50 years, substantial potential exists for emission reduction through the establishment of circular material systems. This study investigates this potential by analysing 26 Environmental Product Declarations (EPDs) and life cycle datasets from across Europe covering the period from 2007 to 2023. To ensure comparability, all data were normalised to a declared unit of 1 kg of roofing membrane. The reinforcement layers were categorised into glass and polyester & glass composites, and their differences were examined using Welch’s t-tests. Correlative analyses and linear as well as multiple regression models were then applied to explore relationships between environmental indicators and the shares of organic and mineral mass fractions. The findings reveal that renewable energy sources, although currently representing only a small share of total production energy, provide a major lever for reducing nearly all environmental impact categories. The type of reinforcement layer was also found to influence the demand for fossil resources, both materially and energetically. For most environmental indicators, only multiple regression models can explain at least 30% of the variance based on the proportions of organic and mineral inputs. Overall, the study underscores the crucial importance of high-quality, transparently documented product data for accurately assessing the sustainability of building products. It further demonstrates that substituting fossil energy carriers with renewable sources and optimising material efficiency can substantially reduce environmental burdens, provided that methodological consistency and clarity of indicator definitions are maintained. Full article

The Influenza A Virus (IAV) is known to hijack cellular proteins during its replication. IAV infection increases the expression of Heat-shock-protein family A (Hsp70) member 5 (HSPA5) in human cells, but its specific function in the viral life cycle remains unclear. This study aims to elucidate the function of HSPA5 in IAV replication, by implementing HSPA5 knockdown (KD) in A549 cells and assessing its impact on IAV’s viral protein translation, genomic RNA transcription, and the host cellular proteome. HSPA5 KD significantly reduced progeny virus release, although viral RNA levels were unaffected. Interestingly, levels of viral structural proteins increased in HSPA5 KD cells after infection. Treatment with HSPA5 inhibitor also suppressed IAV replication, confirming its role as a host dependency factor. Proteomic profiling revealed 116 proteins altered in wild-type cells and 223 in HSPA5 KD cells, with 32 uniquely dysregulated in wild-type and 139 unique to HSPA5 KD cells. In HSPA5 knockdown cells, the altered proteins were linked to pathways such as EIF2, EGF, PEDF, CNTF, IL-13, and G-protein receptor signaling, as well as to cellular processes like lymphocyte activation and regulation of immune and blood cell death, which were not affected in wild-type cells after IAV infection. Overall, this study suggests that HSPA5 contributes to late stages of IAV replication, likely assembly or maturation, and represents a promising target for antiviral drug development. Full article

Currently, an active debate is underway among the academic community, urban planners, and policymakers regarding optimal models of urban development, given that the majority of the population now resides in cities. One concept under discussion is the 15 min city, which posits that all urban residents should be able to reach key, frequently used services within a 15 min walk or cycle. Although the literature suggests numerous potential benefits, debate persists about whether such cities would be optimal from the standpoint of sustainable development objectives and residents’ quality of life. The ongoing discussion also concerns the extent to which existing cities are capable of aligning with this concept. This is directly linked to the actual spatial distribution of individual services within the city. The literature indicates a research gap arising from a shortage of robust case studies that would enable a credible assessment of the practical implementation of this idea across diverse cities, countries, and regions. This issue pertains to Poland as well as to other countries. A desirable future scenario would involve comprehensive mapping of all cities, with respect to both the spatial distribution of specific services and related domains such as the quality and coherence of linear infrastructure. This article presents an analysis of the spatial accessibility of basic urban services in the context of implementing the 15 min city concept, using the city of Koszalin (Poland) as a case study. This city was selected due to its representative character as a medium-sized urban centre, both in terms of population and area, as well as its subregional functions within Poland’s settlement structure. Koszalin also exhibits a typical spatial and functional layout characteristic of many Polish cities. In light of growing challenges related to urbanisation, climate change, and the need to promote sustainable mobility, this study focuses on evaluating access to services such as education, healthcare, retail, public transport, and green spaces. The use of Geographic Information System (GIS) tools enabled the identification of spatial variations in service accessibility across the city. The results indicate that only 11% of Koszalin’s area fully meets the assumptions of the 15 min city concept, providing pedestrians with convenient access to all key services. At the same time, 92% of the city’s area offers access to at least one essential service within a 15 min walk. Excluding forested areas not intended for development increases these values to 14% and 100%, respectively. This highlights the extent to which methodological choices in assessing pedestrian accessibility can shape analytical outcomes and the interpretations drawn from them. Moreover, given this article’s objective and the adopted analytical procedure, the assumed pedestrian walking speed is the key parameter. Accordingly, a sensitivity analysis was conducted, comparing the reference scenario (4 km/h) with alternative variants (3 and 5 km/h). This approach demonstrates the extent to which a change in a single parameter affects estimates of urban-area coverage by access to individual services reachable on foot within 15 min. The analysis reveals limited integration of urban functions at the local scale, highlighting areas in need of planning intervention. This article proposes directions for action to improve pedestrian accessibility within the city. Full article

This study investigates the fatigue behavior of pressurized pipelines under cyclic internal pressure, focusing on the influence of elastic and elastoplastic material responses on crack propagation. The Extended Finite Element Method (XFEM), implemented in Abaqus 2002, is used to model crack initiation and propagation without remeshing. The analysis first considers elastic behavior to estimate maximum stresses and stress intensity factors (SIFs) at crack tips, and then introduces an elastoplastic model to account for local plastic deformation in regions of high stress concentration, improving fatigue life prediction accuracy. The numerical approach is coupled with the Basquin and Manson–Coffin fatigue models and supported by a test matrix varying internal pressure amplitudes to systematically evaluate parameter interactions. The novelty of this work lies in the systematic study of the interaction between internal pressure, material nonlinearity, plastic zone evolution, crack closure, and fatigue life estimation. Unlike previous studies, the analysis includes detailed comparisons with analytical predictions and validated experimental data from the literature, ensuring the reliability of the model. The results show significant differences between the elastic and elastoplastic regimes: under 12 MPa, the maximum stress reached 352.5 MPa and fatigue life was 1639 cycles, while under 28 MPa, stress increased to 850 MPa and life dropped to a single cycle. These findings highlight the critical role of plastic deformation in fatigue crack growth and demonstrate that neglecting plasticity can greatly overestimate pipeline durability, providing a more realistic assessment of structural integrity in pressurized systems. Full article

The multifunctional role of forests in supplying renewable biomaterials and delivering ecosystem services (ESs) is often overlooked in standard life cycle assessment (LCA) methodologies, despite its relevance for sustainable construction. This study developed the BioCons Impact Compensation Model (ICM), which integrates ES into life cycle inventory (LCI) databases and quantifies proprietary BioCons Mitigation Indicators, capturing additional environmental information, ensuring transparency, and preventing greenwashing. Using structural Scots pine in Spain as a case study, the GWP_-luluc-roots indicator was found to be 226.84 kg CO_2-eq/FU, representing 36% of the biogenic carbon (616.45 kg CO_2-eq/FU), highlighting the contribution of root-derived carbon to long-term soil carbon storage. The BioCons Mitigation Indicators demonstrate that mitigation generally exceeds environmental impacts, except for HTP-nc-inorganics, with surplus ES available as biocredits to offset emissions in other life cycle stages. Integrating these indicators into environmental product declarations (EPDs) provides a transparent and accurate view of environmental performance. The results validate the hypothesis that forest bio-based construction products (FBCPs) act as carriers of ESs embedded in derived products, supporting more comprehensive and robust sustainability assessments. Full article

Accelerating urbanization and the intensifying pace of climate change have heightened the occurrence of urban pluvial flooding, threatening urban sustainability. As the preferred approach to urban stormwater management, coupled gray and green infrastructure (GI–GREI) integrates GREI’s rapid runoff conveyance with GI’s infiltration and storage capacities, and their siting and scale can affect life-cycle cost (LCC) and urban drainage system (UDS) resilience. Focusing on Fengxi New City, China, this study develops a multi-objective optimization framework for the GI–GREI system that integrates GI suitability and pipe-network importance assessments and evaluates the Pareto set through entropy-weighted TOPSIS. Across multiple rainfall return periods, the study explores optimal trade-offs between UDS resilience and LCC. Compared with the scenario where all suitable areas are implemented with GI (maximum), the TOPSIS-optimal schemes reduce total life-cycle cost (LCC) by CNY 3.762–4.298 billion (53.36% on average), rebalance cost shares between GI (42.8–47.2%) and GREI (52.8–57.2%), and enhance UDS resilience during periods of higher rainfall return (P = 20 and 50). This study provides an integrated optimization framework and practical guidance for designing cost-effective and resilient GI–GREI systems, supporting infrastructure investment decisions and climate-adaptive urban development. Full article

Over the past few decades, the concept of sustainable agriculture has gained popularity. However, the notion of sustainable agriculture is highly imprecise and unclear, making its application and execution exceedingly challenging. Moreover, disagreements about what sustainability means can lead to a deeper understanding of the intricate empirical procedures and possibly debatable principles involved in any effort to achieve sustainability in agriculture. Practices to increase crop resilience, lower chemical inputs, and boost efficiency are examples of future developments. This review identifies how agricultural life cycle assessment (LCA) studies engage with climate-related metrics such as GHG emissions and land use changes, offering insights for adaptation and mitigation strategies. This review also addresses the need to synthesize existing research on how agriculture and food systems can become more environmentally friendly through LCA. LCA enables the identification of environmental hotspots within agricultural systems, therefore, guiding efforts to limit resource consumption and emissions. For this purpose, a search of a bibliographic database was carried out and the results obtained were analyzed with the open-source tool bibliometrix. There were 2328 results in total with publication years from 1993 to 2025, the latter of which refers to a pre-publication. Then, a post-processing analysis of 1411 articles was conducted and a narrative review of around 100 publications was carried out, where agricultural practices with LCA, current trends, and research gaps were explored. Finally, this paper contributes by identifying three major research gaps derived from the literature synthesis: firstly, the underrepresentation of dynamic LCA models in agriculture; secondly, the lack of geographical balance in case studies; and thirdly, the insufficient integration of socio-economic dimensions in environmental assessments. Full article

The study analyzed energy, environmental impact, and costs in intensive broiler production systems in the southeast of the state of Minas Gerais, Brazil, comparing scenarios with and without photovoltaic systems. Four configurations were evaluated, considering different ventilation types (positive and negative pressure) and photovoltaic generation. The Life Cycle Assessment (LCA), with a functional unit of 1 kg of live weight of chicken and a cradle-to-gate approach, indicated that photovoltaic systems reduce between 2.58 t and 4.96 t of CO₂-eq annually, in addition to offering better energy efficiency. Economically, sheds with positive pressure ventilation have the lowest cost–benefit ratios, while the feeding subsystem was the one that contributed the most to global warming, among the environmental impact categories evaluated in the LCA. Photovoltaic systems demonstrated the potential to reduce electricity costs between 19.4% and 26.5% per year. However, coffee husks used as chicken litter accounted for 36.5% of production costs, highlighting the need for more economical alternatives. It was concluded that photovoltaic systems are a viable solution to reduce environmental impacts and increase profitability, reinforcing the importance of resource-use optimization strategies in poultry farming. Full article

By 2050, global population growth will lead to a significant increase in demand for animal-based products, including seafood. Aquaculture is a key solution to meet these needs while reducing pressure on wild aquatic stocks. However, its environmental footprint and energy demand remain open concerns. This study explores the co-location of offshore aquaculture with a wave energy converter—WaveRoller—as a renewable power source. Using a 44-year dataset from the Portuguese coast near Peniche, the analysis evaluates the survivability and operation of the WaveRoller, long-term percentile trends, seasonal energy production, extrapolated extreme events using probabilistic modeling, and confidence intervals for energy costs. A scenario-based range of energy demand is constructed from a baseline blue mussel production of over 400 tons/yr. The K-Means clustering method is applied to reduce data size while maintaining its representativeness. Results show that a 600 kW WaveRoller is similarly suited to operational wave conditions compared to a 1000 kW device, though it excels when aquaculture energy demand peaks in Summertime. The probability that a single WaveRoller fails to meet annual aquaculture energy needs is nearly zero, though, during Summer, it can become statistically significant. The opposite is verified on survivability during Winter, under harsher wave conditions. The Levelized Cost of Energy is calculated for different expenditure scenarios, with minimum values slightly under 200 EUR/MWh being reported only under ideal conditions. Future work should include climate change scenarios and life cycle assessments to better evaluate environmental impacts and techno-economic viability. Full article

Soil degradation, declining fertility, and rising greenhouse gas emissions highlight the urgent need for sustainable soil management strategies. Among them, biochar has gained recognition as a multifunctional material capable of enhancing soil fertility, sequestering carbon, and valorizing biomass residues within circular economy frameworks. This review synthesizes evidence from 186 peer-reviewed studies to evaluate how feedstock diversity, pyrolysis temperature, and elemental composition shape the agronomic and environmental performance of biochar. Crop residues dominated the literature (17.6%), while wood, manures, sewage sludge, and industrial by-products provided more targeted functionalities. Pyrolysis temperature emerged as the primary performance driver: 300–400 °C biochars improved pH, cation exchange capacity (CEC), water retention, and crop yield, whereas 450–550 °C biochars favored stability, nutrient concentration, and long-term carbon sequestration. Elemental composition averaged 60.7 wt.% C, 2.1 wt.% N, and 27.5 wt.% O, underscoring trade-offs between nutrient supply and structural persistence. Greenhouse gas (GHG) outcomes were context-dependent, with consistent Nitrous Oxide (N₂O) reductions in loam and clay soils but variable CH₄ responses in paddy systems. An emerging trend, present in 10.6% of studies, is the integration of artificial intelligence (AI) to improve predictive accuracy, adsorption modeling, and life-cycle assessment. Collectively, the evidence confirms that biochar cannot be universally optimized but must be tailored to specific objectives, ranging from soil fertility enhancement to climate mitigation. Full article

This study investigates the mechanical behavior and fatigue performance of orthotropic steel bridge decks, with a focus on rib-to-deck welded connections and the impact of geometric symmetry on stress distribution. Two full-scale models with full-penetration butt welds were tested under static compression loads, yielding failure forces of 27 kN (experimental) and 26 kN (analytical), with only a 3% difference. Finite element simulations using ANSYS 16.1 validated these results and enabled parametric studies. Rib plate thicknesses ranging from 5 mm to 9 mm were analyzed to assess their influence on stress distribution and deformation. The geometric ratio h′/tr, which reflects the symmetry of the trapezoidal rib web, was found to be a critical factor in stress behavior. At h′/tr = 38 (tr = 7 mm), compressive and tensile stresses are balanced, demonstrating a symmetric stress field; at h′/tr = 33 (tr = 8 mm), and fatigue performance at the RDW root drops by 47%. Increasing h′/tr improves fatigue life by increasing the number of load cycles to failure. Stress contours revealed that compressive stress concentrates in the rib plate above the weld toes, while tensile stress localizes at the RDW root. The study highlights how symmetric geometric configurations contribute to balanced stress fields and improved fatigue resistance. Multiple linear regression analysis (SPSS-25) produced predictive equations linking stress values to applied load and geometry, offering a reliable tool for estimating stress without full-scale simulations. These findings underscore the importance of optimizing h′/tr and leveraging structural symmetry to enhance resilience and fatigue resistance in welded joints. This research provides practical guidance for improving the design of orthotropic steel bridge decks and contributes to safer, longer-lasting infrastructure. Full article

The aviation industry requires a series of actions that will transform its current status, aiming for sustainable operations. Aviation’s end-of-life stream is a pivotal lever for circularity, yet current dismantling and recycling practices leave significant value unrealized. Circular Economy could be considered as a transformational approach to the aviation industry and address its environmental and economic challenges, meeting sustainability principles. This study conducts a PRISMA-guided qualitative systematic review across academic and industry sources to synthesize regulations, technologies, and economics of aircraft decommissioning. It aims to quantify material recovery potential and environmental gains at the aircraft level and assess technology readiness and cost drivers for metals, polymers, and composites. Findings indicate that optimized decommissioning enables high-value part reuse and substantial material recovery (notably aluminum), with associated lifecycle greenhouse-gas avoidance at the aircraft scale. However, high costs, weak regulations, and limited recycling technologies hinder adoption. Results show that optimized dismantling and certified part-reuse pathways can recover up to 85–90% of total aircraft mass, with potential CO₂-emission avoidance of 25–35 t per narrow-body aircraft compared with landfill disposal. Metal recycling technologies (TRL 8–9) already achieve high yields, whereas polymer and composite recycling remain limited (TRL 5–6) by purity and certification barriers. A comparative assessment of EU, US, and Asia–Pacific regulations identifies enforcement and infrastructure gaps hindering implementation. The study introduces an integrated CE roadmap for aviation comprising (i) standards-aligned design-for-disassembly and digital traceability, (ii) accredited MRO-to-reuse networks, and (iii) performance-based policy incentives. Full article

Polyethylene terephthalate (PET) is one of the most widely used plastics globally, and its poor post-consumer management poses serious risks to the environment and human health. Tackling this issue requires innovative strategies that combine recycling and sustainable manufacturing with the principles of the circular economy. This study addresses this challenge by investigating the use of recycled PET, along with reverse logistics, to produce a cell phone holder through additive manufacturing (AM). Characterization was performed using differential scanning calorimetry, thermogravimetric analysis, intrinsic viscosity measurements, and mechanical tensile tests. Environmental and circular performance were evaluated using Life Cycle Assessment (LCA) and the Material Circularity Indicator (MCI), comparing production with 100% virgin PET resin and 100% recycled PET resin. The results showed that the recycled route achieved a tensile strength of 37.7 MPa, with 7.6% strain before rupture, and thermal analysis confirmed its stability during processing. The LCA revealed a 12% reduction in overall environmental impacts when recycled PET replaced virgin resin, with electricity consumption identified as the main critical point. The circularity assessment suggested potential savings of up to 70% if recycled PET products are reprocessed at the end of their life cycles. These findings demonstrate that combining open-loop recycling with additive manufacturing (AM) can effectively turn waste into high-quality, value-added products, advancing circularity and sustainable material innovation. Full article

Cationic polyelectrolytes, characterized by positively charged functional groups, play an essential role in industries ranging from food solutions, water treatment, medical, cosmetic, textiles and agriculture due to their electrostatic interactions, biocompatibility, and functional versatility. This paper critically examines the transition from petroleum-based synthetic polymers such as poly(diallyldimethylammonium chloride) and cationic polyacrylamides to sustainable natural alternatives derived from agri-forestry resources like starch derivatives and cellulose. Through a cradle-to-gate life cycle assessment, we highlight the superior renewability, biodegradability, and lower carbon footprint of bio-based polycations, despite challenges in agricultural sourcing and processing. This study examines cationization processes by comparing the environmental limitations of traditional chemical methods, such as significant waste production and limited scalability, with those of second-generation reactive extrusion (REX), which enables solvent-free and rapid modification. REX also allows for adjustable degrees of substitution and ensures uniform charge distribution, thereby enhancing overall functional performance. Groundbreaking research and optimization achieved through the integration of artificial intelligence and machine learning for parameter regulation and targeted mechanical energy management underscore REX’s strengths in precision engineering. By methodically addressing current limitations and articulating future advancements, this work advances sustainable innovation that contributes to a circular economy in materials science. Full article