Search Results (479)

Stationary energy storage (SES) is increasingly needed to integrate variable renewable generation and improve consumer self-consumption, but technology choices involve associated trade-offs between cost, efficiency, and life-cycle impacts. This study evaluates the role of second-life lithium-ion (Li-ion) batteries repurposed from electric vehicles for stationary applications, compared to lead-acid (Pb-acid) batteries and power-to-hydrogen-to-power (PtH₂P) systems. We develop an optimization-based sizing and dispatch framework using measured PV–load profiles and hourly market electricity prices, and evaluate performance per 1 MWh delivered to the load over a 10-year life cycle. Economic performance is quantified through discounted cash flows equal to levelized cost of storage (LCOS), while environmental performance is assessed through life-cycle metrics with explicit representation of recycling and second-life credits. In addition to global warming potential (GWP), the analysis considers additional resource and impact metrics, as well as key operational efficiency metrics, including bidirectional consumption efficiency, autonomy, and share of self-consumption/export of photovoltaic systems. Scenario and sensitivity analyses examine the impact of policy and financial parameters, in particular feed-in tariff remuneration and discount rate, on the comparative ranking of technologies. The results highlight how circular economy pathways, especially second-life distribution for Li-ion batteries and high end-of-life recovery for lead-acid batteries, have a significant impact on the life-cycle burden for delivered energy, while market-driven conditions for dispatching and export activities shape economic outcomes. Overall, the proposed workflow provides a transparent, circularity-aware basis for selecting stationary storage technologies associated with photovoltaic systems, under realistic operational constraints. Full article

Addressing the persistent challenges of low resource utilization efficiency and the difficulty in quantifying hidden costs within the beef cattle sector, this study proposes an integrated diagnostic methodology that couples Material Flow Cost Accounting (MFCA) with Value Stream Mapping (VSM). Using a cohort of 1623 beef cattle finished in 2024 at the case study farm in Heilongjiang Province, China, the full life-cycle accounting reveals that hidden costs constitute 6.43% of total inputs. Attribution analysis further pinpoints two critical nodes: feed loss and bedding consumption, which account for 33.14% and 35.77% of negative product costs, respectively. Based on these diagnostics, two optimization strategies were devised: refined feed supply chain management and a recycled bedding system centered on the aerobic fermentation of cattle manure. Empirical estimates indicate that upgrading hardware facilities could reduce the feed loss rate to under 2%, yielding annual savings of ¥485,200. Furthermore, the bedding recycling system not only achieves zero waste discharge but also generates an average annual displacement income of ¥3.504 million, with an investment payback period of just 0.54 years. These findings demonstrate the efficacy of the coupled MFCA-VSM model in identifying environmental costs and unlocking economic potential, thereby providing an actionable pathway for the livestock industry’s transition toward more intensive and circular practices. Full article

The integration of rapidly renewable biomass into insect production systems has been proposed as a strategy to improve resource-use efficiency in insect production. This study evaluated the graded inclusion levels of dried watermeal (Wolffia globosa) in diets of two-spotted crickets (Gryllus bimaculatus) and assessed voluntary nutrient regulation under free-choice feeding. Four fixed-inclusion diets (0%, 25%, 35%, and 45% watermeal) and one self-selection treatment were tested over 28 days. Growth performance, feed conversion ratio (FCR), survival rate (Surv), production index (PI), and whole-body composition were determined. Repeated-measures analysis using linear mixed-effects models indicated that treatment, week, and their interaction were statistically significant (p ≤ 0.024). However, partial R² analysis showed that the independent contributions of treatment and week were negligible, whereas the treatment × week interaction explained measurable variance, indicating that dietary effects were primarily expressed through time-dependent responses. Segmented regression identified a breakpoint at 35% watermeal inclusion (95% CI: 24.93–45.07), indicating that PI was the highest within a moderate supplementation range under the present fixed-diet conditions rather than at a precise single optimum. Inclusion levels beyond this threshold reduced performance. Under free-choice conditions, crickets progressively increased watermeal intake with age and maintained stable nitrogen-free extract (NFE):crude protein (CP) and gross energy (GE):CP intake ratios, selecting an average of 25–35% watermeal over the experimental period. This supplementation range improved feed efficiency and protein deposition while limiting lipid accumulation, suggesting improved energy–protein balance and nutrient partitioning. The self-selection result is interpreted as evidence of behavioral intake regulation under choice conditions and not as direct validation of the segmented-regression breakpoint. Collectively, these findings provide complementary statistical and behavioral evidence supporting a biologically relevant moderate inclusion range (approximately 30–35%) of dried watermeal. Full article

The sustainable valorization of food waste is essential for advancing the circular bioeconomy and reducing the environmental impacts of organic waste disposal. This study presents an integrated approach combining hydrothermal carbonization (HTC) and anaerobic digestion (AD) to recover renewable energy and valuable resources from food waste. The process was simulated in Aspen Plus^® version 14.1 using thermochemical and biochemical reaction models to evaluate the effects of feed moisture (60–85%) and HTC temperature (180–280 °C) on performance. Integration of HTC and AD increased overall energy recovery by 26–38% compared to standalone AD, with a feed moisture of 85%, organic loading of 4 kg VS m⁻³ d⁻¹, and mesophilic/thermophilic temperatures of 35 and 55 °C. Improvements resulted from higher methane yield (0.42 m³ CH₄ kg⁻¹ VS) from HTC liquor and energy-rich hydrochar (25–29 MJ kg⁻¹). The techno-economic assessment indicated a net energy ratio of 2.3, an Internal Rate of Return (IRR) of 18.6%, and a 4.8-year payback period, confirming economic viability. Sensitivity analysis highlighted energy prices and feedstock costs as key drivers, while Monte Carlo simulation demonstrated stability under ±20% uncertainty. Optimal conditions (HTC at 220 °C, 65% moisture, and 100 kg h⁻¹ solid loading) significantly enhanced profitability and carbon efficiency. Overall, the integrated HTC–AD process offers a technically, economically, and environmentally sustainable route for converting food waste into renewable energy and biochar, supporting circular bioeconomy and net-zero energy goals. Full article

Global poultry production continues to expand rapidly to meet the growing demand for affordable and high-quality animal protein. However, this growth raises pressing concerns about environmental sustainability, natural resource use, and public health. Although current initiatives, such as improved housing systems, optimized feeding practices, and partial soybean meal substitution, have helped mitigate some impacts, comprehensive integrated solutions remain underexplored. This review synthesizes emerging nutritional and management innovations that enhance the sustainability of poultry production while maintaining profitability. It addresses three central research questions: (1) Which alternative feed ingredients most effectively preserve animal performance while minimizing environmental burdens? (2) How can environmental management practices enhance resource efficiency and waste valorization? (3) What roles do life cycle assessment methodologies and policy frameworks play in advancing sustainable poultry systems? Evidence from 100 peer-reviewed studies, industrial data, and field analyses reveals that incorporating insect meals, algae, and agro-industrial by-products can reduce dependence on soybean meal by 20–40% and improve feed efficiency by 5–12% across various poultry production systems. Furthermore, integrating environmental management strategies, such as manure valorization, efficient water and energy use, and the adoption of renewable energy, substantially reduces greenhouse gas emissions and promotes circular economic principles. Life cycle assessment studies confirm that combined dietary and management interventions yield greater reductions in carbon footprint than isolated measures. Future research should focus on optimizing interactions among feed strategies, environmental management, and policy frameworks through digital technologies, nanomaterial-based feed additives, and region-specific sustainability plans to accelerate the transition toward resilient, climate-smart poultry production systems. Full article

Livestock represent a key asset in the livelihood of smallholder farmers and play a critical role in the social dynamics and nutritional security of resource-poor communities. However, within these resource-poor communities, livestock productivity remains low. This is often due to seasonal changes in the quantity and quality of available feed from the natural veld, which in turn also contributes to methane production. This study aimed to evaluate the effects of supplementing Eragrostis curvula hay with Searsia lancea leaf or silage meal on in vitro fermentation efficiency and gas and methane production. Therefore, an in vitro study using a semi-automated pressure transducer technique was conducted on grass hay alone (control) and grass hay supplemented with 15% or 30% of either S. lancea leaf or silage meal. The dietary treatments were arranged in a complete randomized design, with each treatment replicated four times. Total gas and methane production was recorded at 3, 6, 12, 24 and 48 h using a pressure transducer attached to a data logger. After incubation, samples were collected to determine volatile fatty acids. Supplementing grass hay with 15% S. lancea leaf meal increased gas production by 76%, 52%, 32% and 12% in the first 24 h of incubation. Similarly, increasing the supplementation level to 30% increased gas production by 75%, 63%, 45% and 14%. However, supplementing grass hay with silage meal at 15% significantly reduced gas production by 37% during the first 3 h of incubation, whereas supplementation at 30% had no effect. Supplementing grass hay with S. lancea meals effectively reduced methane production at 24 and 48 h. Grass hay supplemented with 15% or 30% silage meal reduced methane by 46% and 39% at 24 h, while at 48 h, methane was reduced by 39% and 49%, respectively. Supplementing grass hay with S. lancea meals, however, did not affect volatile fatty acids. In conclusion, S. lancea can be strategically used as a supplementary feed source to modulate the rumen ecosystem by attenuating enteric methane production. Further studies are required to determine the effect of S. lancea on rumen microbial composition and its metabolic function. Full article

Sustainable aquaculture growth necessitates innovative strategies to meet the global protein demand while minimizing environmental impacts. This narrative review synthesizes the current understanding and emerging approaches for optimizing nutrient cycling and trophic transfer efficiency in pond-based aquaculture systems. We highlight two primary strategies: ‘demand-oriented feeding’, which adaptively balances feed inputs with natural food availability, and the ‘nutritious pond concept’, which enhances pond ecology through carbon/nitrogen ratio management and waste-driven nutrient recycling. A critical examination of the scalability and environmental trade-offs associated with these strategies is also presented. Despite the challenges presented by these strategies, their combination could create a more dynamic, ecosystem-based approach to aquaculture that is more resource-efficient and environmentally friendly, contributing to the development of ponds as sustainable, productive ecosystems that enhance efficiency, reduce waste, and support economic viability. Finally, we explored polyculture as an ecological strategy, highlighting its synergistic mechanisms for maximizing food web efficiency and its potential to enhance the two primary strategies. Full article

Coal preparation tailings from the K18 seam of the Abayskaya mine were evaluated as a potential secondary source of critical rare earth elements (REEs). The study showed that REEs are predominantly associated with the mineral fraction of coal; therefore, during beneficiation, approximately 70% of their total content is transferred to flotation tailings. The concentrations of valuable elements in the tailings are as follows (g/t): Li—65; Sc—16; Y—17; Yb—2.5; V—135; and Ti—2293. These values significantly exceed the Clarke values and are comparable to those of some low-grade primary ores, indicating the potential of coal preparation wastes as a technogenic raw material for critical elements. To extract REEs from the resistant aluminosilicate matrix, a fluorine–ammonium sulfate thermochemical activation method was proposed. Using a probabilistic–deterministic experimental design approach, a mathematical model of the process was developed and optimal parameters were determined (400 °C, 120 min, (NH₄)₂SO₄ consumption—140% relative to Al, NH₄HF₂ consumption—110% relative to Si), providing a feed liberation degree (by Al extraction) of up to 94%. Under optimal conditions, high leaching efficiencies of key elements were achieved: Sc (95%), Y (100%), Yb (100%), and Li (100%). The results demonstrate the significant potential of coal preparation tailings as a secondary resource of rare earth elements and confirm the efficiency of fluorine–ammonium sulfate technology for processing this type of technogenic waste. Full article

Barley remains the fourth most cultivated cereal crop worldwide and is valued for its versatility in malting and brewing, animal feed, human nutrition, and dietary supplements. The identification of genotypes suitable for breeding or specific end-use applications requires multi-environment testing to evaluate agronomic performance, grain quality, and trait stability. In this study, a panel of 50 winter barley genotypes (two-row and six-row) originating from diverse genetic backgrounds was evaluated over three growing seasons (2021–2023) under the environmental conditions of southeastern Romania. Seven traits were analyzed, including three phenological traits (heading time, flowering time and plant height), grain yield, and three quality parameters (thousand-grain weight, protein content, and starch content). Environmental conditions had a strong influence on phenological development and grain yield, whereas grain quality traits showed relatively greater stability, indicating a stronger genetic control. Multivariate analyses (Principal Component Analysis (PCA) and Genotype plus Genotype-by-Environment interaction biplot (GGE biplots)) revealed clear relationships among traits and highlighted contrasting adaptive strategies between the two barley types. In two-row barley, genotypes such as Idra and Sandra combined favorable yield performance with stable grain quality traits and therefore represent promising candidates for breeding programs and large-scale cultivation. In six-row barley, SU-Ellen and LG Zebra showed high productivity and strong starch accumulation, making them valuable genetic resources for yield-oriented breeding, although further improvement in nitrogen use efficiency may be beneficial. The 2022–2023 growing season represented the most restrictive environment, emphasizing the importance of stability under stress conditions. Genotypes located close to the Average Environment Coordination axis (AEC axis) during that season, such as Ametist (six-row) and Lardeya (two-row), may represent promising material for breeding programs targeting drought resilience. Overall, the results expand the phenotypic characterization of winter barley germplasm and identify valuable genetic resources that can support pre-breeding efforts and the development of climate-resilient barley cultivars. Full article

Low Earth Orbit (LEO) mega-constellations are becoming the backbone of global communications, yet their cybersecurity remains critically under-addressed. Intrusion detection systems (IDSs) for such constellations face a unique trilemma of accuracy, efficiency, and interpretability under extreme SWaP-C (size, weight, power, and cost) constraints. We present FedLTN-CubeSat (FedLTN refers to Federated Logic Tensor Networks), a neuro-symbolic federated learning framework for intrusion detection in LEO CubeSat constellations. The framework first employs a lightweight spatio-temporal separable perception encoder to efficiently extract features from telemetry and IQ data, designed to operate within the computational budgets of resource-constrained on-board processors. These features feed into a differentiable first-order logic layer based on Logic Tensor Networks, which incorporates domain knowledge as logical axioms to guide learning and enhance interpretability. To enable collaborative learning across a constellation, FedLTN-CubeSat introduces an intra-orbit symbolic federated learning mechanism that aggregates only the logic-layer parameters via inter-satellite links, drastically reducing communication overhead while preserving data privacy. Furthermore, an orbit-adaptive predicate migration module transfers learned rules across different orbital configurations with minimal supervision, facilitating rapid deployment. We evaluate on two benchmarks: the CuCD-ID dataset (NASA NOS3 telemetry) and the STIN dataset (satellite-terrestrial integrated networks). FedLTN-CubeSat achieves 0.98 F1-score on CuCD-ID and 0.96 accuracy on STIN—significantly outperforming prior federated learning baselines (7% improvement) while incurring a minimal daily communication load per satellite. The framework also outputs interpretable decision traces grounded in logical axioms, enabling operators to understand and validate detections. Logical constraints improve detection of unseen attack variants by 25% over pure neural baselines. Full article

Alfalfa (Medicago sativa L.) is a major forage legume worldwide. Developing multifoliolate germplasm has been explored as a strategy to improve forage nutritive value and support more efficient forage livestock production. Here, we developed a multifoliolate population, SJ-ML, using CRISPR/Cas9-generated palmate-like pentafoliate mutants as donor parents. Molecular and phenotypic analyses indicated a stable inheritance of the edited alleles and the multifoliolate trait in SJ-ML. SJ-ML was evaluated under solar greenhouse and field conditions, with the recipient cultivar ‘Aohan’ as the greenhouse control and the commercial cultivars ‘Galaxie-Max’ and ‘GN5’ as field controls. SJ-ML showed a greater leaf area and a higher leaf-to-stem ratio, without reductions in yield or plant height. Nutritive analyses indicated that SJ-ML had a higher crude protein content, relative feed value, digestible dry matter, and dry matter intake, while acid detergent fiber, neutral detergent fiber, and lignin were lower than those of the controls. Across regrowth stages, SJ-ML generally maintained a higher nutritive value than controls. These results support SJ-ML as a multifoliolate germplasm resource for improving nutritive value without a trade-off in agronomic traits, with potential relevance for sustainable agriculture through enhanced forage protein value and a reduced reliance on supplemental protein in some ration contexts. Full article

Brackish aquaponics is expected to be a promising approach to sustainable food production, integrating saline water resources with simultaneous co-cultivation of fish and halophytes. The present study investigated the effects of three feeding ratios (FR1.5: 1.5%, FR3: 3%, and FR6: 6% b.w/d) on the growth performance of European sea bass (Dicentrarchus labrax) and glasswort (Salicornia europaea) co-cultured in three autonomous one-loop recirculation aquaponic systems (180 L each) at 20 ppt salinity over 78 days. Each system comprised three fish-rearing tanks connected to a two-stage sump filter and a nutrient film technique (NFT) hydroponic subsystem. Sea bass fed at FR3 achieved significantly higher weight gain, specific growth rate, and feed conversion efficiency than FR1.5. At FR6, feed consumption nearly doubled compared to FR3 (3.79 vs. 1.91 g), yet the feed conversion ratio increased from 0.79 to 1.65, and protein efficiency ratio declined from 3.80 to 1.91, indicating overfeeding effects. Regarding glasswort, FR6 produced significantly higher chlorophyll a content and plant biomass, whereas FR1.5 showed superior ammonia removal efficiency. Overall, FR3 provided the best balance between fish growth, plant yield, and water quality maintenance. These findings highlight the critical role of feeding management in brackish aquaponics in order to optimize nutrient coupling between fish and halophyte production. Full article

The rapid expansion of the poultry industry has led to the large-scale generation of feather waste, creating serious environmental and public health concerns due to the recalcitrant nature of keratin. Poultry feathers are composed mainly of highly cross-linked keratin proteins stabilized by numerous disulfide bonds, which confer resistance to conventional proteolytic enzymes and natural degradation processes. This review examines the potential of keratinolytic fungi and their enzymes as sustainable, eco-friendly, and value-added strategies for poultry feather waste management and resource recovery. It discusses the environmental and health risks associated with improper feather disposal, such as pathogen proliferation, odor generation, and ecosystem contamination. Conventional management approaches, steam pressure hydrolysis, mechanical grinding, thermal treatment, acid–alkali hydrolysis, and oxidation, are critically evaluated in terms of efficiency and environmental impact. The review further highlights biological degradation pathways mediated by keratinolytic fungi and enzymes, with emphasis on fungal genera such as Aspergillus and Chrysosporium. Key mechanisms of fungal keratin degradation, including sulfitolysis, proteolysis, deamination, hyphal penetration, enzyme secretion, and biofilm formation, are discussed. Finally, industrial, agricultural, and feed applications of keratinases, along with advances in strain improvement, omics technologies, synthetic biology, and associated biosafety and regulatory considerations, are addressed. Full article

Accurate and physiologically relevant in vitro models are needed to predict nutrient digestibility and hindgut fermentation in pigs, as conventional in vivo trials are resource-intensive and raise animal welfare concerns. This study evaluated and compared the predictive performance of three in vitro digestion approaches—shaking (S), dialysis (D), and a combined shaking plus dialysis (SD) method—for estimating in vivo apparent total tract digestibility (ATTD) and fermentation characteristics across weaning, growing, and finishing pigs. Commercial diets were subjected to simulated gastric and small-intestinal digestion using S, D, or SD, followed by fecal inoculation to model hindgut fermentation for 12 and 48 h. During the gastrointestinal phase, crude protein digestibility was highest with D (>75%), intermediate with SD, and lowest with S (50–60%), indicating that product removal by dialysis mitigated enzyme inhibition from metabolite accumulation. After 48 h of fermentation, all methods showed strong linear correlations with in vivo ATTD (r > 0.93), but only D achieved high absolute agreement (Lin’s CCC > 0.95 for dry matter and crude protein). Moreover, D and SD at 48 h closely reflected in vivo fecal profiles of skatole, indole, and microbial enzyme activities, with D at 12 h showing an especially strong correlation for protease (r = 0.98). While D provided the most precise predictions of absolute values, the SD method offered an optimal balance between physiological relevance and operational efficiency, supporting its use as a robust, high-throughput platform for porcine feed evaluation and fecal nitrogenous odorant prediction. Full article

To address the problem of excessive sulfur in high-sulfur magnetite concentrates when used directly, this study systematically investigated the desulfurization behavior and mechanism during oxidative roasting. Green pellets were prepared by mixing high-sulfur iron concentrate fines with 1% bentonite, followed by roasting experiments in air at 800–1200 °C. Thermogravimetric analysis (TG), real-time flue gas analysis (DOAS), X-ray diffraction (XRD), and scanning electron microscopy–energy dispersive spectroscopy (SEM–EDS) were employed to characterize the process and products. The results show that sulfur release is mainly concentrated in two stages: intensive oxidative decomposition of FeS/FeS₂ in the range of 480–580 °C and release of reacted sulfur originally encapsulated within the pellets in the range of 940–1080 °C. It was found that alkali metal oxides CaO and MgO in the feed can fix sulfur at a high temperature. They react with released SO₂ and iron oxides to form Ca/Mg sulfate–iron oxide composite phases, such as (Ca_0.75Mg_0.25)SO₄·0.38Fe₂O₃ and (Ca_0.91Mg_0.09)SO₄·3.66Fe₂O₃·1.47MgO, which slow the SO₂ emission rate. A desulfurization ratio above 99% can be achieved when roasting at 1100 °C and above. This study clarifies the sulfur migration mechanism during the roasting of high-sulfur iron concentrate pellets, providing a theoretical basis for optimizing the roasting process to achieve efficient desulfurization and recovery of iron resources. Full article