Search Results (5,062)

Due to its implications for environmental conservation, the search for alternative ingredients to replace conventional raw materials destined for animal feed is a highly relevant issue. This systematic review aims to identify the fruit with the greatest potential for use in animal feed among those commonly cultivated in the Colombian Pacific region. A bibliographic search of scientific articles on eight different fruits commonly cultivated in the Colombian Pacific was carried out in the Scopus and Web of Science databases. Using the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) methodology, 970 publications from 2004 to 15 December 2024 were selected. After screening the publications, naidí (Euterpe oleracea) was selected as the fruit with the greatest potential for use in animal feed due to the quantitative and qualitative characteristics of the 53 relevant publications found in the databases. The articles were classified by subject matter: nutritional composition, bioactive compound content, and uses in animal feed. The results indicate that naidí is a good source of fat and fiber and has a suitable mineral and fatty acid profile for animal feed. It also contains a variety of chemical constituents, including polyphenols such as anthocyanins and other flavonoids. The multiple precedents found related to the use of naidí in animal feed, such as good indicators of weight gain, increased immune values, antioxidant capacity, and other health benefits, make this fruit and its by-products a promising source as an ingredient for animal feed. This expands the perspective and projection of the naidí industry in Colombia. Full article

As one of the most important finishing machining means of internal helical gear, the residual stress that appears during profile grinding plays an important role in transmission performance and the service internal helical gear. In this research, the residual stress simulation model of internal helical gear profile grinding is established to optimize and predict grinding parameters by means of a neural network. The grinding process parameters (including grinding depth, grinding feed speed, and grinding wheel linear speed) are taken as variable factors. Through experimental verification, the maximum error of the simulation value is 12.8%. The radial basis function (RBF) neural network is introduced, and simulation data samples are used to train and test the residual stress prediction model. Three groups of unknown grinding parameters are predicted, and the relative errors between the predicted and measured values are 5.16%, 1.63%, and 3.39%, respectively. The results demonstrate that the RBF neural network residual stress prediction model proposed in this paper is accurate and feasible. At the same time, the residual stress prediction method provides a theoretical basis for optimizing and controlling the precision of internal helical gear profile grinding. Full article

Food processing wastewater (FPW) poses significant environmental risks due to its high nutrient load yet offers untapped potential as a low-cost feedstock for high-value compound production. This review critically evaluates the valorization of FPW for astaxanthin production through the mixotrophic fermentation of microalgae. Key microalgal species (e.g., Haematococcus pluvialis and Chromochloris zofingiensis) effectively remediate nutrients (nutrients removal of up to 100%) while synthesizing astaxanthin under stress-inducing conditions, such as nutrient starvation, salinity, and oxidative stress. Advanced strategies, such as two-stage cultivation, nutrient profile adjustment, and microbial co-cultivation, which could enhance astaxanthin yields and wastewater treatment efficiency were reviewed comprehensively. The resulting astaxanthin-rich biomass demonstrates multifunctional benefits in animal feed, improving meat quality, immunity, growth, and shelf life. However, this review identifies some challenges, including wastewater management risks, low digestibility of microalgae biomass, and astaxanthin instability during feed processing, which should be addressed properly in real-world applications. This integrated approach aligns with circular bio-economy principles, transforming FPW from an environmental liability into a resource for sustainable biotechnology. Full article

Plant Microbial Fuel Cells (PMFCs) represent a promising technology that uses electroactive bacteria to convert the chemical energy in organic matter into electrical energy. The addition of carbon pellet on electrodes may increase the specific surface area for colonization via bacteria. Use of nutrients such as urea could enhance plant growth. Our study aims to address the following questions: (1) Does carbon pellet layering affect the electrical performance of PMFCs? (2) Does urea treatment of the plants used to feed the PMFCs affect the electrical performance? A new prototype of PMFC has been tested: the plant pot is on the top, drainage water percolates to the tub below, containing the Microbial Fuel Cells (MFCs). To evaluate the best layering setup, two groups of MFCs were constructed: a “Double layer” group (with carbon pellet both on the cathode and on the anode), and a “Single layer” group (with graphite only on the cathode). All MFCs were plant-fed by Spathiphyllum lanceifolium L leachate. After one year, each of the previous two sets has been divided into two subsets: one wetted with percolate from plants fertilized with urea, and the other with percolate from unfertilized plants. Open circuit voltage (mV), short circuit peak current, and short circuit current after 5 s (mA) produced values that were measured on a weekly basis. PMFCs characterized by a “Single layer” group performed better than the “Double layer” group most times, in terms of higher and steadier values for voltage and calculated power. Undesirable results regarding urea treatment suggest the use of less concentrated urea solution. The treatment may provide consistency but appears to limit voltage and peak values, particularly in the “Double layer” configuration. Full article

Simulation-based studies can support breeders’ decisions inexpensively, since there is no need to perform a new procedure. The objective was to assess the efficiency of recurrent genomic selection in panmictic population under additive–dominance and additive–dominance with epistasis models. We assumed two broiler chicken populations with contrasting linkage disequilibrium (LD) levels, 38,500 SNPs, and 1000 genes controlling feed conversion ratio. We applied recurrent genomic selection over seven cycles. The genomic selection efficacy, expressed as realized total genetic gain, was proportional to the LD level and genotypic variance. Genomic selection required model updating to achieve a higher efficacy. The training set size required by genomic selection can be as low as 10%/generation. Under this low-cost scenario, the genomic selection efficacy was slightly lower than the maximum efficacy. There is no difference between genetic evaluation methods regarding the decrease in the genotypic variance due to selection. In general, additive value prediction accuracies and realized genetic gains were highly correlated. The accumulated inbreeding level was not high due to avoidance of sib cross. The genomic inbreeding coefficient over generations was close to zero. Except for dominant epistasis, the efficacy of genomic selection was 4.1 to 46.2% lower than the efficacy under no epistasis. Full article

The present study examined the impact of adding methionine (Met) and its conjugated form (Met-Met) on Cornu aspersum snails. The primary focus was on the animals’ growth performance, the chemical composition of their carcass (whole body without the shell), the mineral profile, and the mechanical properties of their shells. In two experiments conducted under controlled laboratory conditions, diets supplemented with varying levels of Met addition (0.3, 0.6, 1.4 g/kg feed) were used, and the effects of free methionine, Met-Met and their mixture (1.4 g/kg feed) were compared. The study incorporated measurements of body weight, shell width, and mortality of snails. Analyses encompassing protein, fat, sulphur amino acids, glutathione levels, oxidative stress indices (DPPH, TAC, TBARS), and macro- and micronutrient content of carcass and shells were conducted. The findings demonstrated that adding 1.4 g Met/kg feed significantly enhanced the shells’ weight gain (+56% vs. Control), shell weight (+56%) and crushing force (+135%). Furthermore, an increase in the Met content of the carcass was observed (+18%), along with elevated carcass Ca (+28%) and P (+30%) and higher shell Ca (+12%) and Zn (+87%), alongside reduced carcass Fe (−38%) and Cu (−19%). In Experiment II, the Met-Met group exhibited the highest carcass weight (+16% vs. Control), the greatest carcass-to-body weight ratio, and the highest proportion of mature individuals (+27%). Moreover, Met-Met supplementation improved Cu absorption and retention in the carcass (+19%). Also, the results suggest that the conjugated form of methionine may improve Cu absorption and storage in the carcass (+19%). The study’s findings indicate that methionine addition, especially in Met-Met form, can substantially impact the efficiency of C. aspersum farming, enhancing both the productivity outcomes and the quality of the product. That is particularly important in increasing the shell’s mechanical resistance and the carcass’s nutritional value. Full article

Methane pyrolysis produces hydrogen (H₂) with solid carbon black as a co-product, eliminating direct CO₂ emissions and enabling a low-carbon supply when combined with renewable or low-carbon heat sources. In this study, we propose a hybrid geothermal pyrolysis configuration in which an enhanced geothermal system (EGS) provides base-load preheating and isothermal holding, while either electrical or solar–thermal input supplies the final temperature rise to the catalytic set-point. The work addresses four main objectives: (i) integrating field-scale geothermal operating envelopes to define heat-integration targets and duty splits; (ii) assessing scalability through high-pressure reactor design, thermal management, and carbon separation strategies that preserve co-product value; (iii) developing a techno-economic analysis (TEA) framework that lists CAPEX and OPEX, incorporates carbon pricing and credits, and evaluates dual-product economics for hydrogen and carbon black; and (iv) reorganizing state-of-the-art advances chronologically, linking molten media demonstrations, catalyst development, and integration studies. The process synthesis shows that allocating geothermal heat to the largest heat-capacity streams (feed, recycle, and melt/salt hold) reduces electric top-up demand and stabilizes reactor operation, thereby mitigating coking, sintering, and broad particle size distributions. High-pressure operation improves the hydrogen yield and equipment compactness, but it also requires corrosion-resistant materials and careful thermal-stress management. The TEA indicates that the levelized cost of hydrogen is primarily influenced by two factors: (a) electric duty and the carbon intensity of power, and (b) the achievable price and specifications of the carbon co-product. Secondary drivers include the methane price, geothermal capacity factor, and overall conversion and selectivity. Overall, geothermal-assisted methane pyrolysis emerges as a practical pathway to turquoise hydrogen, if the carbon quality is maintained and heat integration is optimized. The study offers design principles and reporting guidelines intended to accelerate pilot-scale deployment. Full article

The tasks and objectives of grassland management have changed significantly in recent decades. One of the key elements of adapting to climatic and economic challenges is the optimal use and future sustainability of grasslands. Ferenc Balázs’s plant stand assessment method is a fast, efficient and widely applicable method for evaluating the quantitative and qualitative characteristics of forage in grasslands, as well as the economic value of pastures. This study is based on a three-dimensional coenological survey which is low-cost, does not require technical infrastructure, and empirically considers the species’ preference by livestock. As a result of our extended criteria approach, we assigned modified forage value (k-value) categories to 2310 vascular plant species. Based on our investigations in the presented case study, the Balázs method was proven to be well suited for estimating the yield of grasslands and determining the relative forage value of grasslands with a high degree of confidence in practice. As this method is non-destructive and involves little trampling, it is particularly suitable for monitoring grassland habitats with a high density of protected plant and animal species. Full article

The agro-industrial residue known as hemp cake, derived from non-psychoactive Cannabis sativa L., represents a sustainable alternative for the development of protein-rich ingredients. In Ecuador, particularly in Bolívar Province, this by-product has been underutilized. However, similar challenges in the valorization of hemp residues have also been reported in other regions, where they are often discarded or used as low-value animal feed. These issues are not exclusive to Bolívar, and since protein stability depends primarily on drying and storage rather than geographic relocation, the valorization strategies proposed in this study can be extrapolated to other production zones. Protein concentrates were extracted from freeze-dried flower cake (TL, freeze-dried hemp cake) and oven-dried flower cake (TS, oven-dried hemp cake) using isoelectric precipitation, yielding protein concentrates from freeze-dried cake (CPL) and oven-dried cake (CPS). Protein content was determined using the Dumas combustion method, the Bradford dye-binding method, and the bicinchoninic acid (BCA) method. Functional properties such as solubility, water absorption, oil absorption, foaming capacity, and foam stability were evaluated, together with total phenolic and flavonoid content and in vitro antioxidant and anti-inflammatory activity. Results demonstrated high protein values (up to 90.42%), remarkable functional properties, and strong bioactive potential, supporting hemp cake concentrates as sustainable alternatives for food, nutraceutical, and pharmaceutical applications Full article

Wave-powered desalination systems integrate reverse osmosis (RO) with renewable ocean energy, providing a sustainable and environmentally responsible approach to freshwater production. This study aims to investigate wave-powered RO desalination using supervised and deep machine learning (ML) models to predict the effects of variable feed flow on permeate recovery and salt rejection under dynamic hydrodynamic conditions. Multiple ML models, including Gaussian process regression (GPR), support vector machines (SVMs), multi-layer perceptron (MLP), linear regression (LR), and decision trees (DTs) were systematically assessed for the prediction of permeate recovery and salt rejection (%) using three distinct input configurations: limited physicochemical features (M1), flow- and salinity-related parameters (M2), and a comprehensive variable set incorporating temperature (M3). GPR achieved near-perfect predictive accuracy R² values (~1.00) with minimal errors for permeate recovery and salt rejection, attributed to its flexible kernel and probabilistic design. MLP and SVM also performed well, though they showed greater sensitivity to feature complexity. In contrast, DT models exhibited limited generalization and higher error rates, particularly when key features were excluded. Sensitivity analyses revealed that feed pressure (FP) and brine salinity (BS) were dominant positive influencers of permeate recovery and salt rejection. In contrast, brine flow (BF) and permeate salinity (PS) had negative impacts. Full article

Production industries create high-quality products through effective machining precision, lead times, productivity, cost benefits, and implementing sustainable manufacturing practices. This study compares the effect of cryogenic CO₂ as a cutting fluid with a flooded conventional system and dry turning on the surface roughness, early-stage tool phenomena (including adhesion, material transfer, and built-up edge (BUE) formation), and the chip morphology of aluminum 7075-T6. Taguchi’s L9 orthogonal array is applied to identify the optimal cutting parameters that minimize surface roughness (Ra). Cutting speed (Vc), feed rate (f), depth of cut (ap), and the type of cutting fluid condition were defined at three levels. The surface roughness (Ra) was determined, and the built-up edge (BUE) and chip morphology were evaluated. Moreover, SEM and energy-dispersive X-ray spectroscopy (EDX) were employed to characterize the machined surface and the cutting tools. The optimal values for the cryogenic cooling and cutting parameters are as follows: 220 m/min (Vc), 0.05 mm/rev (f), and 0.5 mm (ap). These conditions yield a surface roughness mean (Ra) of 0.736 µm, improving the surface roughness by 10.57% compared with the lowest Ra value from all of the tests. In addition, ANOVA showed the feed rate to be the most significant cutting parameter over surface roughness under the given conditions. Regarding chip morphology, snarled chip shapes are associated with low surface roughness values. The results indicate that cryogenic cutting fluid enhances the machined surface quality and reduces the built-up edge compared with dry and flooded conditions. Full article

To date, the grinding behavior of saprolite and lateritic overburden mixtures remains poorly understood. The Bond Work Index (BWI) is the principal indicator used to determine the specific energy consumption during the grinding process. To establish the F₈₀ and P₈₀ values, granulometric distribution models—Rosin–Rammler (RR), Gates–Gaudin–Schuhmann (GGS), and the Swebrec function (SWEF)—were evaluated. The mineral phases of the feed samples were analyzed by X-ray powder diffraction. This study provides evidence that the RR function is the most suitable for simulating the particle size distribution of the feed material, with residual errors below 6.30% and a coefficient of determination (R²) exceeding 97%. After the grinding equilibrium cycle is reached, the SWEF model proves to be the most appropriate, exhibiting residual errors under 3.50% and R² values above 98%. BWI reveals that saprolite is the most difficult ore to grind, with specific energy consumption increasing from 16.38 kWh/t to 25.50 kWh/t as the proportion of saprolite in the mixture rises. This reflects a clear upward trend, as confirmed by a fitted model with an R² of 98.54%. In contrast, the grindability index (Gbp) decreases, indicating that the material becomes increasingly resistant to grinding as the saprolite content increases. This may be attributed to inherent material properties, such as hardness, or to physical phenomena related to fragmentation. The declining Gbp further suggests that greater energy input is required to achieve additional particle size reduction. Overall, the findings demonstrate that saprolite is inherently difficult to grind and behaves according to its own grinding characteristics, regardless of whether it is processed alone or in combination with lateritic overburden. Full article

This study investigated the effects of individual and combined supplementation of eucalyptus essential oil (EEO) and soy isoflavones (SI) on the growth performance, intestinal health and meat quality of weaned meat rabbits. A total of 120 Ira female rabbits were stratified by body weight (BW) and randomly allocated into four treatment groups. The rabbits were fed for 35 days using (a) basal diet (Control), (b) basal diet + 150 mg/kg EEO, (c) basal diet + 25 mg/kg SI, or (d) basal diet + 150 mg/kg EEO + 25 mg/kg SI. The results showed that supplementing EEO and SI in the diet had a synergistic effect on production performance by increasing BW and average daily gain and reducing the feed intake/gain ratio. The EEO + SI group exhibited the most pronounced improvement in growth performance. Compared with the Control group, individual or combined supplementation significantly increased both semi-clean slaughter and total eviscerated slaughter rates, and showed a synergistic effect when supplemented together. The antioxidant capacity of the rabbits was enhanced, with the EEO + SI group showing the largest improvement. Serum biochemical analysis revealed that the combined treatment improved hepatic and cardiovascular functions. Additionally, we observed that the combined addition of EEO and SI has a synergistic effect on increasing the height of intestinal villi and the villus height/crypt depth ratio. Moreover, EEO and SI synergistically improved meat quality by elevating pH value, water-holding capacity, tenderness, and fat proportion. Notably, supplementation of EEO and SI in the diet regulated the composition of the intestinal microbiota, demonstrating increased relative abundance of beneficial Bacteroides and Lachnospiraceae_NK4A136_group. In conclusion, the combination of EEO and SI outperformed individual supplements in promoting growth and intestinal barrier function, potentially through enhancing antioxidant activity, attenuating oxidative stress, protecting the hepatic/cardiovascular systems, and improving intestinal morphology and microbial composition, thereby collectively enhancing growth performance, slaughter traits, and meat quality. Full article

The green macroalgae Ulva Linnaeus, 1753, also known as sea lettuce, is one of the most ecologically and economically significant algal genera. Its representatives occur in marine, brackish, and freshwater environments worldwide and show high adaptability, rapid growth, and marked biochemical diversity. These traits support their ecological roles in nutrient cycling, primary productivity, and habitat provision, and they also explain their growing relevance to the blue bioeconomy. This review summarizes current knowledge of Ulva biodiversity, taxonomy, and physiology, and evaluates applications in food, feed, bioremediation, biofuel, pharmaceuticals, and biomaterials. Particular attention is given to molecular approaches that resolve taxonomic difficulties and to biochemical profiles that determine nutritional value and industrial potential. This review also considers risks and limitations. Ulva species can act as hyperaccumulators of heavy metals, microplastics, and organic pollutants, which creates safety concerns for food and feed uses and highlights the necessity of strict monitoring and quality control. Technical and economic barriers restrict large-scale use in energy and material production. By presenting both opportunities and constraints, this review stresses the dual role of Ulva as a promising bioresource and a potential ecological risk. Future research must integrate molecular genetics, physiology, and applied studies to support sustainable utilization and ensure safe contributions of Ulva to biodiversity assessment, environmental management, and bioeconomic development. Full article

Global warming, driven by greenhouse gas (GHG) emissions, is accelerating globally and highlights the need for effective mitigation strategies. This study assesses the economic feasibility of rainbow trout aquaculture by incorporating GHG emissions into its analysis, thereby contributing to mitigation efforts in the fisheries sector. Focusing on two farming systems—recirculating aquaculture systems (RAS) and flow-through systems (FTS)—we estimated GHG emissions and conducted an economic evaluation using data collected through field surveys. The average GHG emission was 7.14 kg CO₂ eq per kilogram of trout produced, with RAS showing lower emissions than FTS. Electricity and feed were identified as the primary emission sources. The economic analysis revealed an average net present value (NPV) of USD 987,609 and an internal rate of return (IRR) of 18%, with RAS outperforming FTS in profitability. A sensitivity analysis under carbon pricing showed that economic feasibility was maintained, but the NPV declined by about 24% under the carbon tax scenario. Overall, these findings underscore the importance of balancing profitability and emission reduction for sustainable aquaculture management. Full article