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In a growing world population scenario, greater demand for food and in turn agricultural input is expected in the coming decades. The development of innovative sustainable amendments and fertilizers such as hydrogels (HGs) relies on this context. HGs are defined as 3D polymeric networks with the ability to absorb and retain a large amount of water (i.e., swellability). HGs swellability makes them ideal platforms for water- and nutrient-controlled release. The literature reflects a notable diversity in HGs composition, properties, and impacts on agroecosystems, resulting in the dissemination of information across multiple publications. Within this context, the primary aim of this scientific review is to systematically compile, critically evaluate, and synthesize the latest findings and relevant literature pertaining to the application of HGs in agroecosystems. We found that this class of materials was consistently found on soil bulk density, crop available water, soil electrical conductivity, cation exchange capacity and main cereal or legume crops performances particularly under moderate water deficit conditions, suggesting their effectiveness for arid and semi- arid areas. Encouraging results were also found on pesticide, agrochemicals, and microorganisms delivering. Thus, the delivery of agronomic inputs with loaded-HG may play a key role in forthcoming agriculture that would minimize the agronomic impact on the environment. Nevertheless, some critical issues still remain open, concerning: (i) the decreased of HG effectiveness following wetting and drying cycles, (ii) the impact of Na+ contained in HG on crop cells, (iii) the HG effect on soil saturated hydraulic conductivity and pH, and (iv) HG biodegradability and their fate into the environment. In conclusion, HGs seem a promising technology to reach/maintain food security and soil health, but future research should address the development of well-defined protocols for producing biowaste-derived HG that will ensure their biodegradability and non-toxicity and will disclose new insights into a circular economy approach agronomy. One of the biggest challenges would be the synthesis of “smart” HG able to respond to environmental stimuli triggering molecule(s) release in soil. [ABSTRACT FROM AUTHOR]

The aim of this study was to assess how the application of Limosilactobacillus fermentum BAL-21-ITTG in alginate-based edible coatings to osmodehydrated papaya pieces affects the physicochemical and organoleptic properties of the fruit. The papaya was sliced, and these pieces were osmodehydrated at 40 °C in a sucrose solution (45 °Brix) for 6 h. Subsequently, the osmodehydrated papaya pieces (OPPs) were dried for an additional 6 h at 40 °C. The OPPs were categorized into four groups and subjected to the following treatments: T1 (coated with a sodium alginate solution and L. fermentum, followed by gelation with CaCl2); T2 (coated with a sodium alginate solution and L. fermentum); T3 (coated with L. fermentum); and T4 (uncoated). Subsequently, the OPPs were stored in polyethylene containers at 4 °C for a duration of 34 days. The viability of L. fermentum and its survival during gastrointestinal simulation, as well as physicochemical, microbiological, and organoleptic properties were assessed during storage. The T1 treatment exhibited increased firmness throughout storage and sustained higher L. fermentum viability (8.88 log CFU/g) with a 98% survival rate during gastrointestinal simulation. The sodium alginate coatings, serving as a carrier for L. fermentum addition, enhanced the organoleptic attributes of the OPPs over the 34-day storage period. Sodium alginate sourced from S. fluitans is suitable for food applications. Therefore, this technology, involving the addition of sodium alginate from S. fluitans and L. fermentum, could be employed for functional food production and industrial applications. [ABSTRACT FROM AUTHOR]

This study presents the development and initial testing of a novel olfactory-based neurofeedback (NFB) system, utilizing electroencephalographic (EEG) recordings. Distinct from traditional visual or auditory NFB, this approach explores olfactory stimuli as the way to deliver NFB. The developed and tested olfactory-based system offers multiple opportunities because olfaction has strong associations with memory and emotional states and therefore can be a sufficiently strong reinforcing stimulus for both classical and instrumental conditioning. The developed system incorporates an EEG apparatus, an automated olfactory display delivering Sniffin' Sticks, and a Python application for EEG-to-NFB signal conversion. We conducted a preliminary evaluation with fifteen participants split into the olfactory NFB, auditory NFB, and mock-olfactory NFB groups. The NFB represented the occipital alpha rhythm. We observed an increase in alpha power in the true NFB groups and a fatigue-related decrease in the mock NFB group. These initial results demonstrate the feasibility of olfactory NFB and establish a framework for this approach. [ABSTRACT FROM AUTHOR]

Cover crops (CCs) can affect the cropping systems’ N dynamics and soil water content (SWC), but optimizing their potential effects requires knowledge of their growth pattern, N accumulation, and mineralization. For this purpose, a 3-year field experiment was initiated in northeast Italy involving a maize-soybean rotation. The objectives of this study were to (i) evaluate the use of time series vegetation indices (VIs) obtained from the Sentinel-2 satellite for monitoring the growth of CCs and estimating their biomass and N uptake at termination; (ii) investigate the effects of different CCs on cash crop yield and SWC; and (iii) use the simulation model CC-NCALC to predict the nitrogen contribution of CCs to subsequent cash crops. Three CC systems were tested: a fixed treatment with triticale; a 3-year succession of rye, crimson clover, and mustard; and a control with no CCs. Satellite imagery revealed that rye and triticale grew faster during the winter season than clover but slower compared to mustard, which suffered a frost winterkilling. Both grasses and mustard produced greater biomass at termination compared to clover, but none of the CC species affected SWC or yield and N uptake of the cash crop. A net N mineralization of all the CC residues was estimated by the model (except for the N immobilization after triticale roots residues). During the subsequent cash crop season, the estimated clover and mustard N released was around 33%, and the triticale around 3% of their total N uptake, with a release peak 2 months after their termination. The use of remote sensing imagery and a prediction model of CC residue decomposition showed potential to be used as instruments for optimizing the CCs utilization and enhancing cropping water and N fertilization management efficiency; however, it must be further analyzed with other CCs species, environmental conditions, and cropping systems. [ABSTRACT FROM AUTHOR]

Tofu is one of the main foods made with soybeans. The aim of this work was to evaluate the effect of L. plantarum and L. fermentum on the volatile compounds and sensorial profile of fermented tofu during ripening. The soy milk was fermented separately with two native strains (L. plantarum or L. fermentum) until reaching a pH of 5.5, and the fermented tofu was obtained. The tofu obtained by acidification with lactic acid was used as a control and was characterized by microbial survival (L. plantarum, L. fermentum, and P. freudenreichii) for 0, 20, and 40 days of storage at 15 °C. Moreover, the lactic and acetic acid content was determined by high-performance liquid chromatography (HPLC), and the volatile compounds were evaluated by gas. Chromatography-mass spectrometry (GC–MS). The results were analyzed by an ANOVA test (P < 0.05). After storage, the lactic acid bacteria (LAB) survived in the fermented tofu at a concentration higher than 8.0 log CFU/g after 40 days of storage. The shelf life of fermented tofu obtained by acidification was fewer than 20 days because of the presence of fungi and yeasts. The hexanal content was reduced by approximately 96% (P < 0.05) in the tofu obtained by fermentation compared with the control. This process for fermented tofu production employing two native strains could be used for industrial purposes. [ABSTRACT FROM AUTHOR]

Optimal utilization of cover crop (CC) residues in conservation tillage systems require fast-running crop-soil simulation models that can accurately predict surface residue decomposition through time, which in turn determines both nitrogen (N) availability for subsequent cash crop and the longevity of residue cover for effective soil protection, soil moisture conservation, and weed suppression. However, existing models either have long execution times or do not consider environmental variables to which surface residues are exposed. As a result, these models are not practical as a decision support tool used by producers. An improved surface residue water potential ( ψ residue ) module that provides fast estimates of hourly ψ residue using easily available weather information was developed and integrated into the existing 'Cover Crop Nitrogen Calculator (CC-NCALC)'. Specific dynamics of surface residue decomposition were accounted for by adjusting decomposition rates based on ψ residue and temperature dynamics, N limitations, and fractional residue mass in contact with the soil. The modified CC-NCALC tool was calibrated and validated using on-farm litter bag decomposition data collected across 99 site-years during 2017–2019 from conservation tillage-based corn (Zea mays L.) systems in the mid-Atlantic and southeastern USA. Both residue mass [calibration: root mean square error (RMSE) = 403 kg ha−1, relative RMSE (rRMSE) = 27%, Willmott's index of agreement (d) = 0.98; validation: RMSE = 483 kg ha−1, rRMSE = 33%, d = 0.97] and N (calibration: RMSE = 9.1 kg ha−1, rRMSE = 34%, d = 0.93; validation: RMSE = 15 kg N ha−1, rRMSE = 48%, d = 0.93) remaining on the soil surface over time were simulated reasonably well by the modified CC-NCALC tool. Accurate accounting of leaching and gaseous losses from high-quality CC residues (i.e., > 5% N) and initial N immobilization from poor-quality CC residues could further improve model estimates. We propose that the modified CC-NCALC tool can be used as a decision support tool to help inform farmers and land managers regarding their residue and N management decisions in CC-based conservation tillage systems. [ABSTRACT FROM AUTHOR]

The effect that the fructans of Cichorium intybus and Agave salmiana have on health, as well as on the growth of some Lactobacillus species, has been demonstrated. The aim of this work was to evaluate the effect of linear and branched fructans on the growth of seven strains and some probiotic characteristics. The molecular identification of seven strains was performed. Moreover, the growth, resistance to antibiotics and simulated gastrointestinal conditions were also evaluated when these microorganisms were grown in a culture medium containing agave and chicory fructans. The strains were identified as Lactiplantibacillus plantarum, Lactiplantibacillus pentosus, Lactiplantibacillus fabifermentans and Lactiplantibacillus paraplantarum. The results suggest that the seven Lactobacillus strains were able to grow using agave (branched) and chicory (linear) fructans. The linear and branched fructans statistically influenced the kinetic parameters. The specific growth rate varied between 0.270 and 0.573 h−1 and the generation time between 1.21 and 2.45 h for all strains and culture media. All strains showed a growth of 9 Log CFU/mL in all the culture media. Production of lactic, acetic, propionic, butyric, formic and succinic acid was influenced by linear and branched fructans (p < 0.05). All the strains survived simulated gastrointestinal conditions greater than 83%. The resistance of Lactobacillus against ciprofloxacin and rifaximin was significantly affected by linear and branched fructans, but survival to gastrointestinal conditions was not affected by the type of substrate. These results highlight the use of the seven strains, which have probiotic potential; therefore, these could be applied in several biotechnological products. [ABSTRACT FROM AUTHOR]

The high susceptibility to deterioration and diseases during the supply chain and/or during the storage of fresh products is a problem in the industry, and edible films are proposed as efficient methods to preserve its quality. The objective was to obtain and characterize silver nanoparticles (AgNPs) and determine their effect on optical, barrier and mechanical properties of alginate-based films. The alginate was extracted from Sargassum fluitans. AgNPs were obtained by green synthesis using Gliricidia sepium. The UV–Vis and dynamic light scattering (DLS) were used to characterize the AgNPs. The antifungal activity of AgNPs was investigated using several fungal strains. Films were formulated by using 2 and 3% alginate, as well as 0, 1, and 2 mg of AgNPs per mL of formulation, with glycerol as a plasticizer. A randomized experimental design was used to test the effect to alginate and the AgNPs concentrations. The results were analyzed by an ANOVA test (p < 0.05). The films were characterized by water vapor permeability (WVP), mechanical properties, opacity, color, glass transition and melting temperatures, as well as scanning electron microscopy (SEM) and energy dispersive X-Ray (EDS) spectroscopy. WVP, optical and mechanical properties of the films were influenced statistically with alginate and AgNPs concentrations. The PVA values varied between 0.83 and 1.74 g mm h−1 kPa−1 m−2. The results demonstrated that films made with higher alginate and AgNPs concentrations exhibited higher tensile strength (20.35 MPa) and elongation at break (74.56%). The AgNPs showed percentages of growth inhibition higher than 79% in all fungal strains tested. The films formulated had attractive properties that are used to extend shelf life of foods. [ABSTRACT FROM AUTHOR]

Ocular optics is normally estimated based on up to 2,600 measurement points within the pupil of the eye, which implies a lateral resolution of approximately 175 µm for a 9 mm pupil diameter. This is because information below this resolution is not thought to be relevant or even possible to obtain with current measurement systems. In this work, we characterize the in vivo ocular optics of the human eye with a lateral resolution of 8.6 µm, which implies roughly 1 million measurement points for a pupil diameter of 9 mm. The results suggest that the normal human eye presents a series of hitherto unknown optical patterns with amplitudes between 200 and 300 nm and is made up of a series of in-phase peaks and valleys. If the results are analysed at only high lateral frequencies, the human eye is also found to contain a whole range of new information. This discovery could have a great impact on the way we understand some fundamental mechanisms of human vision and could be of outstanding utility in certain fields of ophthalmology. [ABSTRACT FROM AUTHOR]