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Introducing legumes into C4-dominated tropical pastures, may enhance their sustainability but has some pasture management constraints. One potential alternative is using arboreal legumes, but several of these species have relatively high condensed tannin (CT) concentrations, which negatively impact forage quality. There is limited knowledge, however, on how arboreal legume leaf CT content varies over the year and how this might impact forage quality. The objective of this 2 year study was to assess the seasonal variation of CT and nutritive value for ruminants of the tropical tree legumes gliricidia [Gliricidia sepium (Jacq.) Kunth ex. Walp.] and mimosa (Mimosa caesalpiniifolia Benth). The research was carried out in the sub-humid tropical region of Brazil on well-established pastures in which either legume was present with signalgrass (Urochloa decumbens Stapf.). We determined CT and nitrogen concentrations, in vitro digestible organic matter (IVDOM), and leaf δ13C and δ15N from January to October of 2017 and 2018. All parameters were affected (P < 0.05) by the interaction between legume species and sampling time, with generally higher leaf CT content for mimosa than gliricidia, and both were reduced at the start of the dry season, although much more drastically for mimosa. The IVDOM was strongly affected by CT content and increased at the start of the dry season, coincidentally when C4 grass forage quality typically decreased. There is a marked species effect, with CT from gliricidia impacting IVDOM more than the same CT content from mimosa. While N concentration from mimosa also increased at the start of the dry season, that for gliricidia did not vary over the year. We conclude that although these arboreal legumes have relatively high CT contents, these reduce during the dry season when CT concentrations coinciding with a reduced forage quality as the protein content for C4 grasses is usually inadequate in this season.

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Moisture activated dry granulation (MADG) is an attractive granulation process. However, only a few works have explored modified drug release achieved by MADG, and to the best of the authors knowledge, none of them have explored gastroretention. The aim of this study was to explore the applicability of MADG process for developing gastroretentive placebo tablets, aided by SeDeM diagram. Floating and swelling capacities have been identified as critical quality attributes (CQAs). After a formulation screening step, the type and concentration of floating matrix formers and of binders were identified as the most relevant critical material attributes (CMAs) to investigate in ten formulations. A multiple linear regression analysis (MLRA) was applied against the factors that were varied to find the design space. An optimized product based on principal component analysis (PCA) results and MLRA was prepared and characterized. The granulate was also assessed by SeDeM. In conclusion, granulates lead to floating tablets with short floating lag time (<2 min), long floating duration (>4 h), and showing good swelling characteristics. The results obtained so far are promising enough to consider MADG as an advantageous granulation method to obtain gastroretentive tablets or even other controlled delivery systems requiring a relatively high content of absorbent materials in their composition.

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This study evaluated bond strength of glass fiber posts to root dentin using push-out (PO) and diametral compression (DC), testing glycolic acid as a conditioner and varying dentin moisture. An additional aim was to test whether DC can be an alternative test to PO for bond strength assessment. Eighty bovine teeth were divided into eight groups (n = 10) defined by the use of either 37% glycolic acid or 37% phosphoric acid (PA) on moist or wet dentin before bonding with either Adapter SingleBond/RelyX ARC or One Step Plus/Duo-Link Bisco. Each tooth provided discs with an internal diameter of 2 mm, external diameter of 5 mm, and height of 2 mm, which underwent PO and DC. Finite element analysis (FEA) was carried out on 3D models. When analyzing PO results through linear regression, the highest values of bond strength were observed using glycolic acid on wet dentin in the cervical and middle thirds of the teeth. Analyzing DC results, the only statistical influence on values was the dental thirds. The scatterplot of the DC results and the PO bond strength values indicated no relationship between the results of the two tests (r = 0.03; p = 0.64). PO test detected more sensitive changes in bond strength values than DC.

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Cronobacter sakazakii is a potentially pathogenic bacterium that is resistant to osmotic stress and low aw, and capable of persisting in a desiccated state in powdered infant milks. It is widespread in the environment and present in various products. Despite the low incidence of cases, its high mortality rates of 40 to 80 % amongst neonates make it a microorganism of public health interest. This current study performed a comparative assessment between current reduction methods applied for C. sakazakii in various food matrices, indicating tendencies and relevant parameters for process optimization. A systematic review and meta-analysis were conducted, qualitatively identifying the main methods of inactivation and control, and quantitatively evaluating the effect of treatment factors on the reduction response. Hierarchical clustering dendrograms led to conclusions on the efficiency of each treatment. Review of recent research trend identified a focus on the potential use of alternative treatments, with most studies related to non-thermal methods and dairy products. Using random-effects meta-analysis, a summary effect-size of 4-log was estimated; however, thermal methods and treatments on dairy matrices displayed wider dispersions - of τ2 = 8.1, compared with τ2 = 4.5 for vegetal matrices and τ2 = 4.0 for biofilms. Meta-analytical models indicated that factors such as chemical concentration, energy applied, and treatment time had a more significant impact on reduction than the increase in temperature. Non-thermal treatments, synergically associated with heat, and treatments on dairy matrices were found to be the most efficient.

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This study analyzed the meteorological and hydrological droughts in a typical basin of the Brazilian semiarid region from 1994 to 2016. In recent decades, this region has faced prolonged and severe droughts, leading to marked reductions in agricultural productivity and significant challenges to food security and water availability. The datasets employed included a digital elevation model, land use and cover data, soil characteristics, climatic data (temperature, wind speed, solar radiation, humidity, and precipitation), runoff data, images from the MODIS/TERRA and AQUA sensors (MOD09A1 and MODY09A1 products), and soil water content. A variety of methods and products were used to study these droughts: the meteorological drought was analyzed using the Standardized Precipitation Index (SPI) derived from observed precipitation data, while the hydrological drought was assessed using the Standardized Soil Index (SSI), the Nonparametric Multivariate Standardized Drought Index (NMSDI), and the Parametric Multivariate Standardized Drought Index (PMSDI). These indices were determined using water balance components, including streamflow and soil water content, from the Soil Water Assessment Tool (SWAT) model, and evapotranspiration data from the Surface Energy Balance Algorithm for Land (SEBAL). The findings indicate that the methodology effectively identified variations in water dynamics and drought periods in a headwater basin within Brazil's semiarid region, suggesting potential applicability in other semiarid areas. This study provides essential insights for water resource management and resilience building in the face of adverse climatic events, offering a valuable guide for decision-making processes.

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Soil water balance is an essential element to consider for the management of droughts and agricultural land use. It is important to evaluate the water consumption of a crop in each of its phenological phases and the status of water reserves during critical hydrologic periods. This study developed an agricultural drought index (Standardized Soil Moisture Deficit Index - SMODI) conceptualized with a water balance model considering the vegetation stress caused by soil moisture deficit. This contribution was based on meteorological information, soil moisture from satellite images, hydrophysical properties of the soil and crop evapotranspiration. Information from 61 weather stations located in the dry zone of Tolima was used for estimating the water balance. SMODI was compared with the most common drought indexes: Standardized Precipitation - Evapotranspiration Index (SPEI), the Palmer Self-Calibrated Drought Index (scPDSI), and other eleven macroclimatic indexes. Pearson's correlation coefficients (r), Tukey's test, and analysis of variance were applied to analyze the degree of association between SMODI and the contrasting indexes on a quarterly basis. SMODI considers factors influencing soil moisture distribution and retention and the water stress thresholds that plants have evolved to withstand during drought periods. Consequently, this integrated approach enhances the assessment of agricultural drought by relying on pertinent physical processes. SMODI identified extremely dry, severe, moderate and normal drought 5 %, 3 %, 20 % and 72 % respectively conditions in areas characterized by Entisols, Inceptisols, and Andisols, where rice and fruit crops and pasturelands are cultivated. The SMODI has a good correlation with macroclimatic indexes (0.70 < r < 0.74).

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The frying process changes can be desirable and undesirable, involving the physicochemical, nutritional, and sensory aspects, depending on the food and oil properties and the frying process. In this context, alternative flours emerge as a strategy for adding value to the food since they are rich in fiber, vitamins, and minerals, contributing to the variability of ingredients and the full use of food, including residues such as seeds and husks. This narrative review aims to gather current scientific data addressing the alternative flour coatings on breaded meat, mainly chicken, products to evaluate the effects on fried products' nutritional value, physicochemical parameters, and sensory attributes. Scopus, Science Direct, Springer, and Web of Science search bases were used. This review showed that alternative flours (from cereals, legumes, fruits, and vegetables) used as coatings increase water retention and reduce oil absorption during frying, increase fibers and micronutrient content, which are not present in sufficient quantities in commonly used flours due to the refining process. These flours also reduce gluten consumption by sensitive individuals in addition to favoring the development of desirable sensory characteristics to attract consumers. Therefore, frying processes in oil promote a reduction in humidity, an increase in oil absorption and energy content, and a decrease in vitamin content. In this context, coatings based on alternative flours can reduce these adverse effects of the frying process.

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The increase in the use of energy from forest biomass has increased the demand for knowledge about tree-chipping operations. Therefore, this study aimed to evaluate the effect of different drying times of wood logs and various combinations of knife and anvil configurations in the horizontal chipper on the quality of Eucalyptus dunnii chips produced for energy purposes. The study was conducted in a seven-year-old stand of E. dunnii. A horizontal chipper was used to chip whole trees and obtain nine types of chips, resulting from the interaction between the three drying times of the trees and three configurations of the horizontal chipper. The chips were characterized, followed by an evaluation of energy quality for comparison between the treatments. Among the outcomes discerned, it became evident that the employed wood exhibited a Basic Density (0.506 g.cm-³). The chip dimensions and bulk density presented notable disparities owing to the distinct chipper configurations and tree drying time. The extended drying period (150 days) conferred a lower average moisture content (34.20%) to the study materials. Moreover, the ash content was lower in the treatment with 150 drying days (0.52%). Both the useful calorific value and the Fuel Value Index were also greater in the treatment (150 drying days), measuring 2600.00 kcal kg-1 and 128.06 cal cm-3, respectively. In the analysis of the Fuel Value Index concerning chipper configurations, it was observed that for chips featuring a granulometry of 25 mm, the treatment involving 150 days of drying, four knives, and one shim proved the most efficient (Q = 0.979). Conversely, for chips with a granulometry of 16 mm, the treatment involving 150 days of drying, eight knives, and one shim emerged as the most efficient (Q = 0.970). Consequently, the proposed index is efficacious and underscores the necessity of adapting knife settings in response to moisture content changes to maintain the desired granulometry and apparent density standards.

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Modeling soil moisture as a function of meteorological data is necessary for agricultural applications, including irrigation scheduling. In this study, empirical water balance models and empirical compartment models are assessed for estimating soil moisture, for three locations in Colombia. The daily precipitation and average, maximum and minimum air temperatures are the input variables. In the water balance type models, the evapotranspiration term is based on the Hargreaves model, whereas the runoff and percolation terms are functions of precipitation and soil moisture. The models are calibrated using field data from each location. The main contributions compared to closely related studies are: i) the proposal of three models, formulated by combining an empirical water balance model with modifications in the precipitation, runoff, percolation and evapotranspiration terms, using functions recently proposed in the current literature and incorporating new modifications to these terms; ii) the assessment of the effect of model parameters on the fitting quality and determination of the parameters with higher effects; iii) the comparison of the proposed empirical models with recent empirical models from the literature in terms of the combination of fitting accuracy and number of parameters through the Akaike Information Criterion (AIC), and also the Nash-Sutcliffe (NS) coefficient and the root mean square error. The best models described soil moisture with an NS efficiency higher than 0.8. No single model achieved the highest performance for the three locations.

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Simulation and rigorous design of industrial dryers combine a large number of models, which feed three fundamental balances: (1) mass; (2) energy; and (3) quantity of movement of the material through the dryer. Many of these models represent physical phenomena affecting the three balances at the same time, which makes these calculations extremely complex, hence, accurate models are essential. The hypothesis that the kinetic stage of drying of any material culminates in the thermodynamic moisture equilibrium between solid and drying gas has been in effect for many years. However, recent findings show that there is a transition stage between the kinetic stage and the thermodynamic equilibrium, which, experimentally, looks like an equilibrium. The beginning of this transition stage or dynamic pseudo-equilibrium stage would mark the end of the drying kinetics models, which has been named as the dynamic pseudo-equilibrium moisture contents (Xdpe). The non-observance of this phenomenon presupposes a model limited in its prediction capacity, especially in the last stages of drying and even more so at low drying temperatures. As a consequence, sizes of industrial dryers could be underestimated during the simulation and rigorous design process, or underestimate drying times, in batch dryers. On the other hand, the optimal conditions may never be found, during the optimization of existing industrial drying processes. The objective of this work is to present the procedure to determine Xdpe, during the experimental determination of drying curves of any material. Likewise, to propose the practical moisture ratio, which uses Xdpe, instead of the equilibrium moisture, to be used in the modeling of the drying kinetics.•The drying process is divided into three stages: kinetic, transition, and equilibrium.•The dynamic pseudo-equilibrium moisture content divides the kinetic and the transition stages.•The practical moisture ratio should be used in rigorous industrial dryer design calculations.