Search Results (345)

Fertilization recommendations are frequently proposed by a limited number of calibration experiments conducted in a few regions, with few cultivars. Thus, recommendations concerning nutrients’ critical levels (CLs) and sufficiency ranges (SRs) are not always the most suitable ones. In addition, it is not known whether CL and SR differ when it comes to peach yield and quality variables, such as pulp firmness or total soluble solids (TSS) concentration. CL and SR can be estimated by using Bayesian segmented quantile regression (BSQR) in combination with databases. The aim is to propose nutrients’ CL and SR in soil and in leaves of peach trees grown under a subtropical climate, by combining databases and BSQR models. The dataset comprised 208 observations of Prunus persica cultivars ‘Maciel’ and ‘Chimarrita’, grown in southern Brazil. Models were developed through plateau regression based on BSQR models to measure the association between dependent variables (fruit yield and quality) and nutrient concentrations in the soil and leaves. CL and SR of N and K in leaves recorded values for variables related to fruit quality, pulp firmness, and TSS lower than values recorded for variables related to yield. We show for the first time that CL and SR in leaves for N and K related to yield are different between cultivars. A similar outcome was recorded for CL and SR of N in leaves between growing regions/sites presenting different soil types and climatic variables. CL and SR of N in leaves related to yield were higher in peach trees grown in sandy-soil sites with low organic matter content. This study presents critical advances for the Southern Brazilian peach market, but with implications for the approach presented in the present study (combination of database and BSQR modeling) relevant for application in orchards around the world. Full article

Microalgae are promising platforms for biomass production, carbon capture, biofuels, and high-value bioproducts. However, despite significant advances in cultivation technologies, reactor engineering, and metabolic engineering, industrial implementation remains limited. This gap suggests that the main challenge of microalgae biotechnology lies not in the availability of productive strains or cultivation systems, but in managing the environmental and physiological heterogeneity that emerges during scale-up. This structured narrative review selected literature using predefined descriptors and relevance-based inclusion criteria and organized the evidence into five thematic domains encompassing cultivation-scale constraints, cellular physiology, bioengineering, precision technologies, and industrial translation. This review examines macrospatial bottlenecks related to light distribution, gas transfer, hydrodynamics, and reactor operation, alongside microspatial constraints involving cell cycle regulation, carbon allocation, metabolic adaptation, and stress responses. Recent advances in adaptive cultivation, real-time monitoring, artificial intelligence, digital twins, computational modeling, and bioengineering are discussed as tools to transform biological and environmental variability into actionable information. Based on concepts established in precision agriculture, this review proposes precision microalgae as a conceptual framework that integrates reactor engineering and cell physiology with three operational pillars: real-time monitoring, predictive modeling, and adaptive control. Its specific contribution is to connect currently fragmented technological and biological advances within a common framework for managing multiscale heterogeneity during cultivation and scale-up. Overall, the available evidence supports the operational logic of this framework, although its generalized effectiveness under industrial conditions remains to be demonstrated. Full article

Medium-carbon steels are susceptible to heat-affected zone (HAZ) hardening during welding. This study evaluated the effects of preheating temperature and joint geometry on mechanized gas metal arc welded (GMAW) joints in 6.3 mm thick SAE 1045 steel. Butt and fillet joints were welded under conventional single-pass conditions from room temperature to 250 °C, while an additional two-pass procedure was evaluated separately. Metallography and hardness were evaluated for both joint geometries, whereas tensile and Charpy V-notch tests were performed only on butt joints. Significant joint geometry × preheating condition interactions were identified for weld metal (WM) area, HAZ area, WM hardness and HAZ hardness. Average HAZ hardness remained below 300 HV₁₀ for all conventional single-pass conditions. Among the butt joint single-pass conditions, no statistically significant effect of preheating was detected for ultimate tensile strength (UTS) or Charpy absorbed energy, and all tensile specimens fractured in the base metal (BM). The two-pass procedure was treated descriptively because the second deposition simultaneously altered multiple welding variables. Overall, the effects of preheating on WM and HAZ areas and hardness were joint-geometry-dependent under the investigated conditions. Full article

The use of crossbreeding between dairy and beef breeds has been adopted as a strategy to add value to male calves from dairy systems, improve productive efficiency, and reduce economic and animal welfare concerns. This study evaluated the effects of Holstein × Angus crossbreeding on productive performance, metabolism, ruminal fermentation, nutrient digestibility, carcass characteristics, meat quality, and fatty acid profile during the feedlot finishing phase. Twenty-four uncastrated male cattle (8 Holstein, 8 Angus, and 8 crossbreds) were confined for 130 days and fed an isoenergetic and isonitrogenous diet. No significant differences were observed among breeds for weight gain, dry matter intake, feed efficiency, or nutrient digestibility (p > 0.05). However, Angus and crossbred cattle showed higher carcass yield compared to Holstein cattle (p ≤ 0.05). Angus and crossbred animals presented higher concentrations of total volatile fatty acids, acetate, and propionate in the rumen (p ≤ 0.05). Breed differences were also observed in erythrocyte indices and serum urea concentrations (p ≤ 0.05). Meat from crossbred animals showed superior quality attributes compared to Holstein, including lower ultimate pH, higher lightness, greater water-holding capacity, and an intermediate lipid profile between the parental breeds (p ≤ 0.05). It is concluded that Holstein × Angus crossbreeding improves carcass yield, ruminal fermentation efficiency, and meat quality, without compromising productive performance, representing a viable strategy for adding value to male calves from dairy herds under tropical production conditions. Full article

Brazil presents a distinctive convergence of continental-scale climatic diversity, extensive urbanization, large-scale biomass burning, rapid land-use change, persistent air-quality monitoring gaps, and deep social inequalities, producing highly heterogeneous and compound environmental health risks. In this context, treating air pollution and climate change as parallel environmental crises obscures their structural interconnections through shared emission sources, mutually reinforcing exposure pathways, and overlapping health and social consequences. In this narrative review, we critically synthesize scientific and institutional lines of evidence and argue that air pollution and climate risks can be more effectively addressed in Brazil through a single strategic agenda for science, public health, and governance. We first discuss why these challenges cannot be managed in isolation, emphasizing the effects of heat, drought, stagnation events, biomass burning, and extreme weather on pollutant formation, dispersion, and health burden. We then examine Brazil as a critical case where recent regulatory advances coexist with structural limitations in monitoring, data integration, and territorial coverage. Based on this diagnosis, we propose an integrated national agenda organized around five mutually reinforcing priorities: monitoring through hybrid networks; predictive science through climate-informed modeling and early warning; public health through the convergence of epidemiology, toxicology, and mechanistic research; equity-oriented research and action through the explicit incorporation of vulnerability, inequality, and climate justice; and policy appraisal through the assessment of disease burden, economic costs, mitigation co-benefits, and trade-offs. We further discuss the governance mechanisms needed to connect these priorities and translate evidence into coordinated action and adaptive public policies. We also argue that the Amazon should be approached not as an isolated ecological exception but as a central component of a broader Brazilian and Global South discussion on environmental health, land-use change, and climate justice. In this scenario, Brazil has the scientific capacity and regulatory momentum to become a reference in the integrated management of air pollution and climate risks, but this will depend on replacing fragmented approaches with a coordinated framework capable of linking exposure, mechanism, burden, inequality, and action. Full article

Spodoptera frugiperda (Lepidoptera: Noctuidae) is a key insect pest of maize in Brazil. However, the evolution of insecticide resistance has raised concerns about the risk of control failures under field conditions. This study assessed insecticide efficacy and estimated the risk of control failure in Brazilian populations of S. frugiperda exposed to selected insecticides. Nine field populations were collected from representative maize-producing regions of Brazil during the 2024/2025 and 2025/2026 seasons. Early third-instar (L3) larvae from these populations were exposed to the highest label rate of ten insecticides representing different modes of action in maize leaf bioassays. Mortality was assessed 96 h after exposure, and the risk of control failure was based on the efficacy threshold of 80% mortality. Significant effects of population, insecticide, and the population × insecticide interaction were detected, indicating variation in susceptibility among the sampled populations. Methoxyfenozide + spinetoram, spinosad, chlorfenapyr, and spinetoram consistently caused high mortality (>81%) and were associated with low risk of control failure across all populations. In contrast, chlorantraniliprole exhibited reduced efficacy with mortality below the expected efficacy threshold in most populations and a high risk of control failure. Population-dependent variation in insecticide efficacy was also evident for metaflumizone, emamectin benzoate, thiodicarb, indoxacarb, and methoxyfenozide, with corresponding variation in the risk of control failure. These findings show that insecticide efficacy and the risk of control failure depend on the specific insecticide–population combination and provide valuable information to support decision-making regarding insecticide selection and the rotation of modes of action within insect resistance management (IRM) and integrated pest management (IPM) programs. Full article

Reliable tools for assessing soil nutrient availability are essential for the accurate determination of fertilizer application rates. The aim of this study was to evaluate the reliability of commercially available electrochemical sensors for the real-time determination of water-soluble N, P, and K in soil as indicators of nutrient supply to crops. The experiment was conducted under both greenhouse and field conditions using seven probe models. Four probes (designated 1–4) were equipped with three sensors for the measurement of N, P, and K. Probes 5, 6, and 7 were equipped with sensors for N, P, K, electrical conductivity (EC), pH, soil temperature, and soil moisture, although probe 7 was manufactured by a different company. Each probe was inserted into 4 L pots filled first with a clay-loam soil and subsequently with a sandy soil. The soils were irrigated with nutrient solutions containing different concentrations of N, P, and K in order to modify nutrient concentrations in the soil solution and compare sensor readings with values obtained through standard chemical analyses. The results showed no significant correlation between probe readings and soil N, P, or K concentrations in either clay-loam or sandy soils. At the same time, all probes exhibited a constant relationship among N, P, and K readings regardless of soil texture or nutrient concentration. This finding suggests that the probe algorithms rely on a single measured variable that is subsequently converted into multiple output variables using fixed conversion coefficients. In conclusion, the NPK probes tested in this study were unable to provide reliable real-time measurements of soil N, P, and K concentrations. Full article

The growing demand for sustainable agricultural inputs has encouraged the development of biotechnological alternatives based on microbe-derived enzymes and bioactive metabolites. In this study, co-fermentation strategies involving different Trichoderma strains were investigated as a process-based approach to enhance the production of enzymes and plant growth-promoting metabolites with agricultural relevance. Distinct culture media compositions and inoculation strategies significantly affected microbial performance and biocatalytic outputs. Optimized co-culture conditions resulted in enhanced conidiation, microsclerotia formation, siderophore production (up to 95%), phosphate solubilization (up to 419 mg mL⁻¹), indole-3-acetic acid synthesis (0.60 mg mL⁻¹), and increased activities of chitinase, β-1,3-glucanase, and protease. Metabolomic profiling by GC-MS revealed the induction of diverse secondary metabolites associated with antimicrobial activity and plant–microbe signaling. Overall, the results demonstrate that Trichoderma co-fermentation is an effective biotechnological strategy to intensify enzyme and metabolite production, highlighting its potential for the development of multifunctional bioinputs for sustainable agricultural applications. Full article

Biodiesel has emerged as a promising renewable alternative to fossil-derived diesel, driven by increasing environmental concerns and the need for sustainable energy sources. Among the various production routes, enzymatic transesterification catalyzed by lipases offers significant advantages, including mild reaction conditions, high selectivity, and reduced formation of by-products. However, the industrial application of free lipases is limited by their high cost, low operational stability, and lack of reusability. In this context, enzyme immobilization has gained considerable attention as an effective strategy to enhance lipase performance and economic feasibility. This review provides an overview of recent advances in lipase immobilization techniques for biodiesel production. Different immobilization methods are discussed, as well as support materials such as polymers, nanomaterials, and hybrid structures. Finally, current challenges and future perspectives are outlined, aiming to guide the development of more robust and cost-effective biocatalytic systems for large-scale biodiesel production. Full article

The growing demand for more sustainable energy alternatives has increased interest in microalgae-based fuels, promising options due to their high biomass productivity, carbon dioxide assimilation capacity, and potential for cultivation using wastewater. However, despite this strong theoretical basis, the industrial consolidation of these routes remains limited, revealing a persistent gap between scientific progress and the technological maturity achieved across specific biofuel pathways. This review examines the current state of the main microalgae-to-fuel conversion routes, emphasizing their technological readiness, proximity to industrial application, and the factors underlying their uneven progress. It also discusses the main opportunities and challenges associated with these biofuels, including cultivation performance, photobioreactor limitations, process intensification, scale-up, integration with waste streams, and downstream processing and product recovery requirements. Overall, this review identifies three main insights. First, the industrial viability of microalgae-based fuels depends less on maximizing individual conversion yields than on overcoming systemic bottlenecks across the production chain. Second, wet biomass conversion routes, particularly hydrothermal liquefaction and anaerobic digestion, appear more compatible with current industrial constraints. Third, lipid- and carbohydrate-based fuels remain more limited by biomass production costs and downstream processing requirements. Accordingly, further progress will depend on process intensification, integrated biorefineries, and technological innovations capable of simultaneously improving productivity, economic viability, and environmental performance. Full article

The increasing generation of solid waste has become a critical environmental and economic challenge worldwide, demanding innovative strategies for sustainable management and resource recovery. In this context, the conversion of solid waste into green materials has emerged as a promising approach to reduce environmental impacts associated with waste disposal. This review provides an overview of recent advances in the transformation of various solid waste streams (including agricultural residues, food waste, industrial by-products, and municipal solid waste) into value-added green materials. Particular emphasis is placed on innovative synthesis processes such as thermochemical conversion, hydrothermal treatments, biological transformations, and advanced physicochemical methods that enable the production of functional materials with enhanced properties. The review also discusses the potential applications of these materials in areas such as environmental remediation, catalysis, energy storage, and construction materials. Overall, the valorization of solid waste into green materials represents a sustainable pathway to reduce environmental burdens while generating high-value products for diverse industrial sectors. Full article

For over 70 years, microalgae have been considered promising ingredients for developing sustainable, nutritionally rich foods. Their high protein content, presence of essential amino acids, fatty acids, natural pigments, and a myriad of bioactive compounds position them as potential alternatives to conventional ingredient sources. However, despite their significant potential, the large-scale incorporation of microalgae into food products remains limited. This study presents a critical analysis of the main challenges associated with the use of microalgae in the food industry. Key bottlenecks include high production costs, technological difficulties related to biomass processing, and challenges in extracting desirable compounds. Additionally, the strong flavor, odor, and intense coloration of microalgal biomass can negatively affect sensory acceptance in food products. Other limitations involve scalability issues in cultivation systems, risks of contamination during production, and regulatory constraints related to food safety approval. Consumer perception and limited familiarity with microalgae-based foods also contribute to slower market adoption. Therefore, although microalgae represent a promising and sustainable food resource, overcoming technological, economic, and sensory barriers is essential for their broader integration into the food industry and for achieving successful market consolidation. Full article

Background/Objectives: Paclitaxel is a chemotherapy drug used to treat various tumours, but its use is often limited by an acute and chronic pain syndrome that is poorly managed. Naringin and its aglycone, naringenin, exhibit antioxidant, antitumour, anti-inflammatory, and antinociceptive effects, making them potential alternative treatments. However, their low water solubility limits their oral bioavailability in humans. Micronisation in a supercritical medium reduces particle size and enhances the dissolution of compounds, offering a possible solution. In this study, we investigated whether micronising naringin and naringenin via supercritical technology could improve their dissolution and oral efficacy against paclitaxel-induced pain syndrome. Methods: Micronisation was performed using supercritical CO₂. Molecular docking was used to analyse the binding of naringin and naringenin to TRPV1, a key target for pain relief. Swiss mice were used in capsaicin (TRPV1 agonist)-induced nociception and paclitaxel-caused acute and chronic pain models. We assessed mechanical, cold, and heat sensitivity, potential adverse effects, and TRPV1 mRNA expression. Results: Micronisation improved the apparent dissolution profile of molecules. Docking results showed that naringin and naringenin bind to TRPV1. Both micronised compounds reduced capsaicin-induced nociception without affecting locomotion or body temperature. Micronised naringin and naringenin alleviated mechanical and cold allodynia, as well as thermal hyperalgesia in both acute and chronic paclitaxel-induced pain, outperforming their conventional forms. They also downregulated TRPV1 mRNA expression in the mice’s sciatic nerve. Conclusions: Taken together, these results show that supercritical micronisation improved the apparent dissolution and oral antinociceptive efficacy of naringin and naringenin, emphasising their potential as promising alternatives for managing paclitaxel-induced pain, with TRPV1 being a probable contributor to the observed antinociceptive effects. Full article

The yield of apple trees as a function of potassium fertilization and the critical levels (CLs) and sufficiency ranges (SRs) of K in the soil, leaves, and fruits were determined in two experiments (two orchards) in four crop seasons. Plants of “Royal Gala” and “Fuji Suprema” cultivars were treated with 0, 50, 100, 150, or 200 kg K₂O ha⁻¹ year⁻¹. Potassium was applied annually during the bud swelling phase and onto the soil surface in the projection of the plant canopy, without incorporation. Critical levels and SR were estimated by Bayesian segmented quantile regression models. The cultivar factor was the main source of variation in fruit yield, K concentration in leaves and pulp, and K exported by apples. The crop season was the second factor with the greatest contribution to apple yield and K concentrations in leaves. When data from all crop seasons and orchards were pooled, yield did not vary by K treatments. The concentration of K in the leaf and fruit pulp also did not change as a function of the K dose with grouped data. For fruit production, the CL of K in the soil was 170 mg dm⁻³ for both cultivars; 17.8 g kg⁻¹ and 15.8 g kg⁻¹ in leaf for “Fuji Suprema” and “Royal Gala”, respectively; 1150 mg kg⁻¹ and 1080 mg kg⁻¹ in fruit pulp for “Fuji Suprema” and “Royal Gala”, respectively. The lack of response to K fertilization indicates that the trees were operating within a nutritional plateau. Consequently, we recommend that K fertilization in subtropical apple orchards be guided strictly by soil and plant analysis. For orchards exceeding the soil critical level of 170 mg dm⁻³ and leaf concentrations of 17.8 g kg⁻¹ and 15.8 g kg⁻¹ in leaf for “Fuji Suprema” and “Royal Gala”, respectively, and 1150 mg kg⁻¹ and 1080 mg kg⁻¹ in fruit pulp for “Fuji Suprema” and “Royal Gala”, respectively, K applications may be reduced or temporarily withheld under similar high-K soil conditions, provided that soil and plant nutritional status are regularly monitored. This management strategy ensures high yields and more efficient and sustainable nutrient management. Full article

Bats are important reservoirs of vector-borne bacteria, including species of Bartonella, yet the ecological mechanisms underlying their circulation in bat–ectoparasite systems remain poorly understood. Here, we investigated the molecular occurrence, diversity, ecological drivers, and interaction structure of Bartonella spp. in cave-dwelling bats and their associated streblid flies in northeastern Brazil. A total of 492 bats were captured across six caves, from which 231 blood samples and 1017 streblid flies were collected. Molecular screening for Bartonella was performed using a qPCR targeting the 16S–23S rRNA intergenic region, followed by characterization with multiple molecular markers (ftsZ, gltA, ribC, and rpoB). Phylogenetic and genotype diversity analyses revealed high genetic diversity, including lineage clustering with previously described bat-associated Bartonella and ftsZ sequences related to ruminant-associated lineages. Ten genotypes were shared across caves, indicating broad spatial circulation. Generalized linear models showed that streblid load did not predict infection in bats, whereas detection varied significantly among streblid species. Network analyses revealed low specialization of Bartonella molecular markers in bats and significantly higher specialization in flies compared to null expectations. Overall, Bartonella dynamics in cave bats were not explained by streblid abundance alone but instead reflect the combined influence of host ecology, ectoparasite identity, and interaction structure. Full article