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Stacking compacted filtered tailings has become an option to cope with the new Brazilian regulations while providing a safe disposal method for the tailings. It has become feasible due to recent developments in dewatering technologies. Still, the dewatering processes may need to be improved to attain acceptable moisture contents considering the on-field compactable range. Also, the filtered material's moisture content is highly influenced by the weather conditions, especially during the rainy season in the southeast of Brazil. Additives are a possible solution to accelerate moisture reduction. However, scientific studies in the technical literature still need to attest to the effectiveness of these methods to tailings, mainly on a full scale. Accordingly, the present research evaluates the performance of two additives to hasten filtered iron ore tailings drying for dry stacking purposes: commercially available quicklime and superabsorbent polymer. Also, undrained triaxial tests were conducted on specimens retrieved from on-field compacted layers to investigate the additive's influence on the tailings' mechanical behaviour. Initial confining pressures ranging from 100 to 600 kPa were used. The results have shown the inefficacy of the superabsorbent additives in boosting the drying process for on-field conditions and the efficiency of the quicklime in doing so. Furthermore, no substantial changes in the mechanical response were observed due to the insertion of quicklime. This highlights the novelty of the present study in the context of iron ore tailings management. [ABSTRACT FROM AUTHOR]

The criteria for selecting materials for railway pavement (particle size distribution, California Support Index, and physical indexes) are not suitable for evaluating the hydraulic behavior of tropical soils under unsaturated conditions, often resulting in the rejection of soils with good mechanical and hydraulic performance. The railway trackbed is exposed to precipitation, allowing water infiltration into the pavement layers and consequently leading to moisture variation. Therefore, the present study aims to assess the moisture variation over time in the railway trackbed when subjected to the action of rainfall. For this purpose, five soils were analyzed as constituent materials of the subballast, with the infrastructure of the Carajás Railway in Brazil being used as a reference. Water retention curves and conductivity tests were conducted using the HYPROP (Hydraulic Property Analyzer) and WP4-C (Water Potential Four) equipment, and numerical modeling was developed using the IVFlow software. The numerical modeling revealed that sample 1 (lateritic sand) performed better compared to the other analyzed soils, as it exhibited lower moisture variation (3.25% above the optimum content) under the influence of rainfall and it also had low permeability. [ABSTRACT FROM AUTHOR]

Asphalt pavement failure is directly related to the traffic and climate effects. Temperature and moisture severely impact pavement service life. It is known that moisture changes the stiffness and stress–strain distribution and all the mechanical behaviors of the mixture/structure. There is a huge interest in studying the impact of water on the behavior of flexible pavements, mainly on freeze–thaw regions under tropical climates with high rainfall levels. The scope of the present paper was to check the susceptibility to moisture-induced damage of dense asphalt mixes produced and applied on highways in Brazil's southernmost region using different laboratory tests: visual adhesion of coarse aggregate; tensile strength ratio (TSR), and dynamic modulus ratio (DMR). Thus, this study evaluated the morphological, chemical, and mineralogical properties of aggregates from 11 quarries, as well as the interaction between aggregates and the respective bituminous binders. Rocks with high Si contents performed worse in visual adhesiveness tests; chemical ratios such as Fe/Si above 1 and Ca/K above 5, as well as the rougher texture of aggregates, considerably improved the coating, reducing the failures in adhesion. Results of TSR and DMR, after applying the induced moisture damage cycle, indicated greater susceptibility to conventional binders than mixtures containing modified binders in their composition. The action of moisture damage for most mixtures caused a reduction in strength and stiffness, warning of a decrease in the binder's ability within the mixture, completely changing the distribution of efforts within the structure. Therefore, from this study, it is possible to suggest using DMR instead of TSR to assess susceptibility to moisture damage. [ABSTRACT FROM AUTHOR]

Grasslands are one of the vegetation types most widely affected by wildfires in southern Brazil. It is a fire-dependent ecosystem and it is necessary to know the hourly fuel moisture variation for its management. The objective of this work is to fit Grass Fuel Moisture Code (GFMC) models to estimate the moisture content for the grassland of the State Park of Vila Velha, Paraná, Brazil. Data sampling to determine the hourly moisture content was performed during the winter of 2018 and divided into two campaigns of five days with stable weather conditions. Destructive samples were taken out for the sorption tests on climatic chambers to obtain the equilibrium moisture content and the time lag values. The fitted equilibrium moisture and time lag models were evaluated by residual distribution analysis, mean absolute error (MAE), root mean square error (RSME) and coefficient of determination (R2). The fitted model performed better than the original GFMC model due to the obtained MAE, RSME and R2 values. The results showed that the fitted GFMC model is better to predict the fine fuel moisture for the region. [ABSTRACT FROM AUTHOR]

Smuggled cigarettes are seized around the world, and a correct destination is needed for this material. In this context, the Federal Revenue of Brazil (RFB) has created Ordinance n°59 of 2019 on the destination of contraband cargo seizures, to which this manuscript aims to propose a use with greater added value. The influence of two factors on the flexural properties of composite samples are studied as follows: i) the influence of prior hydrogen peroxide treatment executed on the cigarette butts (CBs), tested in composite samples made with 50% Polypropylene (PP) and 50% CBs in wt%; and ii) the influence of moisture on composites composed of 60% PP and 40% CBs in wt%, after up to 72 h immersed in water. The fiber treatment has not caused significant reduction of flexural properties in the produced composites, and all composite samples with moisture have showed greater flexural strength (FS) and flexural modulus (FM) than the dry sample. However, these bending properties can decrease as the moisture increases, so further studies are encouraged. It is demonstrated that these composites are feasible to produce, may be used in moist environments in flexural stresses and allow for fiber hydrogen peroxide treatment without significant reduction in flexural properties. [ABSTRACT FROM AUTHOR]

The occurrence of disease outbreaks involving low‐water‐activity (aw) foods has gained increased prominence due in part to the fact that reducing free water in these foods is normally a measure that controls the growth and multiplication of pathogenic microorganisms. Salmonella, one of the main bacteria involved in these outbreaks, represents a major public health problem worldwide and in Brazil, which highlights the importance of good manufacturing and handling practices for food quality. The virulence of this pathogen, associated with its high ability to persist in the environment, makes Salmonella one of the main challenges for the food industry. The objectives of this article are to present the general characteristics, virulence, thermoresistance, control, and relevance of Salmonella in foodborne diseases, and describe the so‐called low‐water‐activity foods and the salmonellosis outbreaks involving them. [ABSTRACT FROM AUTHOR]

This study aimed to provide a critical analysis of official data obtained by Instituto Mineiro de Agropecuária (IMA) regarding the compliance with minimum ripening time (MRT) and moisture criteria defined by the Minas Gerais state, Brazil, for Minas Artisanal Cheese (in Portuguese: Queijo Minas Artesanal, QMA), and how these parameters can influence the counts of hygiene indicator microorganisms. QMA samples collected between January 2010 to May 2023 (n = 1803) were analyzed. Few non-compliant samples were identified due to the denaturation of alkaline phosphatase and presence of starch. High relative frequencies of non-compliance with MRT were identified in QMA samples from producer regions of Cerrado, Serra do Salitre, Araxá and Serro (88.5%, 66.7%, 63.4% and 62.2%, respectively), and high relative frequencies of non-compliance to moisture were identified in QMA samples from Serro, Serra do Salitre and Cerrado (36.5%, 29.0% and 24.4%, respectively). Counts of total coliforms, Escherichia coli and coagulase positive staphylococci were significantly higher (p < 0.0001) in samples in non-compliance to the MRT and moisture content; when these data were analyzed per producing region, this trend was observed only for QMA produced in Serro. The lack of data regarding ripening time hampered a more precise analysis over the years, as this information was absent for all QMA samples collected and processed since 2022 (n = 150): such information should be systematically recorded during QMA sampling for surveillance programs, due to its relevance for identity, quality and safety. Our data also indicate the need to implement educational programs to improve the adequacy of QMA to official criteria. • High relative frequencies of cheese samples non-compliant with ripening time and moisture. • Counts of hygiene indicators were significantly higher in samples non-compliant to ripening time and moisture. • Educational programs are need to improve cheese adequacy to official criteria. [ABSTRACT FROM AUTHOR]

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., (© 2024. The Author(s).)

The measurement of the fine dead fuel moisture content (FDFMC) is extremely important for forest fire prevention and suppression activities, as it has a great influence on the ignition probability and fire behavior. The Fine Fuel Moisture Code (FFMC) from the Fire Weather Index (FWI), is one of the most used models to estimate the FDFMC. Nevertheless, studies that assess the efficiency of this model in Brazil or in low latitude regions are rare. The present study aimed to evaluate the efficiency of the FFMC in an equatorial climate area and to develop a new model capable of estimating the FDFMC with greater precision. For this purpose, 861 random samples of fine dead fuel had their moisture content determined through oven drying. The obtained values were compared with those estimated by the FFMC and correlated with meteorological parameters to build a regression model. The results obtained show that the FDFMC was overestimated by the FFMC. The independent variables with the greatest influence on the FDFMC were, in decreasing order of significance: air relative humidity, air temperature, amount of rainfall in the last 24 hours and number of days without rainfall. The developed model presented good statistical parameters (r² = 0.86; p <0.0001; RMSE = 0.22) and can be used, in areas with similar characteristics of the study area, to estimate the daily fire risk and to determine ideal conditions for prescribed burns. [ABSTRACT FROM AUTHOR]

The daily cycle of atmospheric conditions related to squall‐line (SL) initiation over the northern coast of Brazil (NCB) was obtained for a specific month (March) over the course of a decade (2004–2013). March falls during the NCB's rainy season. A comparison of atmospheric conditions between two categories, the most intense SL events (SLC+) and the weakest coastal convection events (CC–), was carried out. For both categories, the daily cycle of convective cluster properties (i.e. number and area) over the NCB showed that the transition from shallow to deep convection occurred from 1200 to 1500 UTC, and the development of multicell storms occurred from 1500 to 1800 UTC. From 1800 to 2100 UTC for the SLC+ events, the number of clusters decreased sharply, and the area slightly expanded, which indicated upscaling via merging; for the CC– events, merging was a secondary mechanism, and the clusters did not experience upscaling. Atmospheric conditions were computed from the ERA‐Interim reanalysis data. By focusing on the significant differences between the categories, it was found that SL initiation was related to a higher moisture content at approximately 700 hPa for all analysis times (0600, 1200, 1800 and 0000 UTC) and to a stronger low‐level moisture convergence from 0600 to 1800 UTC, mid‐level upward motion from 1200 to 0000 UTC, low‐level convergence at 1200 UTC, and upper‐level divergence from 1800 to 0000 UTC. [ABSTRACT FROM AUTHOR]

• An approach is proposed to assess extreme rainfall-triggered landslides. • 3D unsaturated flow is coupled with the infinite slope method. • Extreme precipitation events are investigated using soil depth models. • 1-year spin up for moisture conditions has little impact on the safety factor. • Simple soil depth models are viable options for landslide susceptibility studies. The susceptibility to shallow landslides is affected by several factors. Rainfall intensity, soil thickness distribution, and antecedent moisture conditions are components that influence the spatio-temporal prediction of landslides at the watershed scale. Yet, the combined impact of these factors on the susceptibility to landslides has been overlooked. The purpose of this paper is to investigate landslides triggered by extreme precipitation in the Tijuca Massif, Rio de Janeiro, southeastern Brazil. Our approach couples a 3D variably saturated flow solver with the infinite slope stability method to calculate the statistical distributions of the safety factor and the pore pressure at the soil–bedrock interface. Numerical simulations were performed for 6 scenarios considering 1-year spin-up time for soil moisture and different spatially distributed soil depths. The results show that during extreme precipitation events, soil depth and initial moisture conditions may not have much influence on the safety factor, as the intensity and duration of rainfall will be the triggering agents. Comparison of simulated unstable zones and field data from mapped landslide scars further supported this conclusion. We conclude that simple soil depth models are feasible options for regional studies of landslide susceptibility. Our findings are relevant to understanding shallow landslides induced by extreme rainfall in Rio de Janeiro and other regions with similar geological and climate settings. [ABSTRACT FROM AUTHOR]

ABSTRACT This paper examines the distributions of anomalies of sea surface temperature ( SST) and of the moisture sources in the South Atlantic Ocean during extreme dry events in southeastern Brazil in the austral autumn, winter and spring for the period 1982-2009. The extreme dry events were identified based on a combination in which consecutive dry days and variable percentiles were considered in five homogeneous regions in terms of precipitation in southeastern Brazil, as defined through cluster analysis. Composites of anomalies of SST and moisture sources for the dry events selected for the different homogeneous regions show specific characteristics for each region, but some similarities were apparent for the southern and northern parts of southeast Brazil. During spring in all regions, and during autumn and winter in the southern regions, a tripole pattern of SST anomalies was found (negative, positive and negative), together with an anomalous anticyclonic circulation in the Atlantic Ocean transporting moisture to southern Brazil associated with positive SST anomalies. A decrease in the climatological moisture sources in the south of Brazil then ensues, and dry conditions prevail in the regions of interest. In winter and autumn in the northern regions, the same tripole pattern of SST anomalies was also found, but shifted northwards. An anomalous cyclone is associated with the negative SST anomalies, and the climatological moisture sources to the northeast of Brazil reduce their contribution to the region of interest, where negative precipitation anomalies are registered. It seems that the events selected show the results of reductions both in terms of the availability of moisture and in atmospheric instability. [ABSTRACT FROM AUTHOR]

The effect of the adjacent non-forested environment on the forest near the edge, edge influence (EI), is an important impact in fragmented landscapes and is believed to vary with factors such as forest structure and edge contrast. In order to improve our understanding of the factors governing the variability in EI, we studied microclimate and vegetation at cerrado edges surrounded by variable land uses in southeastern Brazil, a system with both forest and savanna fragments. We determined the significance, magnitude and distance of EI on microclimate, vegetation structure and grass biomass which we measured along five transects perpendicular to fourteen edges in forest or savanna next to different land uses. We introduce a quantitative measure of edge contrast that considers land uses at different distances from the same edge (e.g., a firebreak between a forest edge and a plantation) and verified whether edge contrast is correlated with EI in this system. Notwithstanding the large variation in EI among variables and study sites, there were some similarities in the patterns of EI between forest and savanna edges. Edge contrast was successfully quantified by our measure but was only correlated with EI on moisture and grass biomass. Our results point to the high variability in EI within a region. Our quantitative measure of edge contrast may be useful in explaining variability in EI. However, much unexplained variation remains in the highly fragmented cerrado system which is affected by EI in both forest and savanna fragments. [ABSTRACT FROM AUTHOR]

Thirty samples of Requeijão Marajoara cheese and thirty samples of Minas Frescal cheese, made both with buffalo milk, were analyzed to determine main components levels and physicochemical characteristics. The cheeses were obtained from industrial establishments located in the municipalities of Salvaterra, Marajó Island, and Moju, northeastern of Pará State. The data were statistically analyzed by Descritive Analyses, using the SAS® system. For the Requeijão Marajoara, the average results obtained were: pH 5.15 (± 0.13); acidity 0.62% (±0,08); moisture 43% (±1.64); fat 31.57% (±3.13); fat on dry extract (FDE) 55.84% (±4.38); protein 34.59 % (±1.68); and ash 2.45% (±0.47). For the Minas Frescal pH 6.26 (±0.69); acidity 0.15% (±0.14); moisture 60.99% (±2.58); fat 25.09% (±1.68); fat on dry extract (FDE) 62.95% (±4.38); protein 11.06% (±1.65);and ash 2.09% (±0.32). The variation between macronutrients and physicochemical characteristics revealed standardization lack in the technology used in the processing, what can be related to the inexistence of specifi c legislations for the elaboration of these flowed from buffalo milk. It's crucial the establishment of criteria for processing and legal requirements, aiming to obtain standardized products, with consequent aggregation of values. [ABSTRACT FROM AUTHOR]

Abstract: This study examined the ability of near-infrared reflectance spectroscopy method (FT-NIRS) and multivariate calibration to estimate the concentration of moisture, protein, lipid, ash and carbohydrate of Brazilian soybeans. The spectra obtained in the range of 4000 to 10,000cm−1 were preprocessed by several combinations of mathematical treatments: MSC (multiplicative scatter correction), SNV (standard normal variate) or first and second derivative and all data were mean centered before the calibration, for which was used the PLS method (partial least squares). The best calibration models found in this study were the ones used to determine protein and moisture contents (R2 =0.81, RMSEP=1.61% and R2 =0.80, RMSEC=1.55%, respectively). However, the technique shows high predictability for all parameters, including lipids, ashes and carbohydrates, with RMSECV of 0.40 to 2.30% and RMSEP of 0.38 to 3.71%. This result shows the viability of using NIR in controlling the quality parameters of soybeans. [Copyright &y& Elsevier]

We examined the effects of soil mesofauna and the litter decomposition environment (above and belowground) on leaf decomposition rates in three forest types in southeastern Brazil. To estimate decomposition experimentally, we used litterbags with a standard substrate in a full-factorial experimental design. We used model selection to compare three decomposition models and also to infer the importance of forest type, decomposition environment, mesofauna, and their interactions on the decomposition process. Rather than the frequently used simple and double-exponential models, the best model to describe our dataset was the exponential deceleration model, which assumed a single organic compartment with an exponential decrease of the decomposition rate. Decomposition was higher in the wet than in the seasonal forest, and the differences between forest types were stronger aboveground. Regarding litter decomposition environment, decomposition was predominantly higher below than aboveground, but the magnitude of this effect was higher in the seasonal than in wet forests. Mesofauna exclusion treatments had slower decomposition, except aboveground into the Semi-deciduous Forest, where the mesofauna presence did not affect decomposition. Furthermore, the effect of mesofauna was stronger in the wet forests and belowground. Overall, our results suggest that, in a regional scale, both decomposers activity and the positive effect of soil mesofauna in decomposition are constrained by abiotic factors, such as moisture conditions. [ABSTRACT FROM AUTHOR]

Cream cheesecurd is a type of processed cheese, originally Brazilian, produced throughout the entire Brazilian territory with some technological variations. This is one of the main types of cheese produced and consumed in Brazil and it is known for presenting an elevated fat content. On the other hand, the fat plays a fundamental role in appearance, flavor and texture of cheese, then developing a light product with sensory quality similar to the traditional version is a major challenge to food industry. In this context, the objective of this study was to evaluate the chemical composition and sensory acceptability of light cream cheesecurd with different levels of fat reduction for texture and overall impression. The experiment followed a design of response surface, the Central Composite Rotatable Design (CCRD) with two factors (fat and moisture). The sensory acceptability was evaluated by 100 consumers, by the hedonic scale of nine points. The results showed that the cheesecurds with different levels of fat reduction had similar sensory acceptability when combined with a proportional increase in moisture content. The products that presented dry defatted extract (DDE) of approximately 19.3%, originated from different combinations of fat and moisture, were those with better acceptance by consumers, demonstrating the importance of DDE in sensory acceptance. [ABSTRACT FROM AUTHOR]

Abstract: One of the variables that have a greater influence on the determination of the moisture buffering capacity of a material to be used as inner surface layer of an enclosure is the value of the vapour resistance of the surface film layer. In this paper, the influence of such a surface resistance on the moisture buffering value (MBV) is studied by means of a small experimental equipment where the tests were developed according to the NordTest protocol, but modifying the air speed over the samples, in order to take in count its influence. The tested material is an autoclaved ceramic made from the shells of the molluscs grown in Brazil, with the aim of using it as indoor surface layer of the enclosures in museums and buildings used to keep archives and documents, and where it is required to control the conditions of the indoor air by means of passive systems based on the moisture buffering capacity of the materials. The theoretical MBV is determined too based on the effusivity of the material which is obtained from its basic hygroscopic characterization. [Copyright &y& Elsevier]

The objective of this paper was to evaluate the treatment and coating of soybean seed using equipment with spray system Grazmec®. The experiment was carried out in the Faculdade de Agronomia Eliseu Maciel of the Universidade Federal de Pelotas, Rio Grande do Sul state, Brazil. The treatments were: 1) control (without equipment), 2) fungicide, 3) amino acid, 4) polymer, 5) fungicide + amino acid, 6) fungicide + insecticide, 7) fungicide + polymer, 8) fungicide + insecticide + polymer, 9) fungicide + amino acid + insecticide, all applied with the equipment. To evaluate the experiment the moisture content determination, field emergence, index of emergency speed, weight of 1000 seeds and intensity of coverage was carried out. The results showed that soybean seed treated and/or coated didn't reach more than 1% with the treatment. The field emergence, index of emergency speed and weight of 1000 seeds weren't affected by treatment and/or coating by spray system. The use of the polymer improves the seed coating when the spray system was used. However the equipment should be regulated when there is change of the product and/or seed to obtain an appropriate coating. [ABSTRACT FROM AUTHOR]

The process of drying of the leaves of Inga edulis, a flavonoid-rich plant from Amazonia, was optimised in a forced convection dryer by combining experimental design and mathematical modelling. First, the monolayer moisture content was determined by hygroscopic studies at 25°C and the value of this parameter (5.86 g/100 g dry matter) was fixed as a minimum to be achieved. Next, a 3² full-factorial design was applied, with temperature (40, 55 and 70 °C) and airflow velocity (0.6, 1.2 and 1.8 m/s) as the independent variables, the dependent variable being the drying time required to reduce the moisture content until the level determined in the monolayer was achieved. Nine kinetic models, with one to four parameters, were fitted to the experimental data. The fitting performance of these models was assessed using statistical criteria and, from these results, the Henderson and Pabis model was found to be sufficient to predict the monolayer drying times. Subsequently, a multiple linear regression was carried out by applying a second-order model to describe the relationship between the independent and dependent variables, which established the adequacy of this model (R² > 0.97) and, thus, the applicability of the combined statistical and mathematical approaches. Finally, an experimental domain that could minimise the drying times (time <40 mm) was determined. An experimental validation of the model was accomplished in a point of this domain and good agreement was found between the experimental and predicted values. Moreover, no flavonol degradation was observed, whereas a loss of 19.4% for the total flavanols was found. [ABSTRACT FROM AUTHOR]

The objective of the present study was to assess for Minas Gerais the cokriging methodology, in order to characterize the spatial variability of Thornthwaite annual moisture index, annual rainfall, and average annual air temperature, based on geographical coordinates, altitude, latitude, and longitude. The climatic element data referred to 39 INMET climatic stations located in the state of Minas Gerais and in nearby areas and the covariables altitude, latitude, and longitude to the SRTM digital elevation model. Spatial dependence of data was observed through spherical cross semivariograms and cross covariance models. Box-Cox and log transformation were applied to the positive variables. In these situations, kriged predictions were back-transformed and returned to the same scale as the original data. Trend was removed using global polynomial interpolation. Universal simple cokriging best characterized the climate variables without tendentiousness and with high accuracy and precision when compared to simple cokriging. Considering the satisfactory implementation of universal simple cokriging for the monitoring of climatic elements, this methodology presents enormous potential for the characterization of climate change impact in Minas Gerais state. [ABSTRACT FROM AUTHOR]

This work examines the sources of moisture affecting the semi-arid Brazilian Northeast (NEB) during its pre-rainy and rainy season (JFMAM) through a Lagrangian diagnosis method. The FLEXPART model identifies the humidity contributions to the moisture budget over a region through the continuous computation of changes in the specific humidity along back or forward trajectories up to 10 days period. The numerical experiments were done for the period that spans between 2000 and 2004 and results were aggregated on a monthly basis. Results show that besides a minor local recycling component, the vast majority of moisture reaching NEB area is originated in the south Atlantic basin and that the nearby wet Amazon basin bears almost no impact. Moreover, although the maximum precipitation in the ''Poligono das Secas'' region (PS) occurs in March and the maximum precipitation associated with air parcels emanating from the South Atlantic towards PS is observed along January to March, the highest moisture contribution from this oceanic region occurs slightly later (April). A dynamical analysis suggests that the maximum precipitation observed in the PS sector does not coincide with the maximum moisture supply probably due to the combined effect of the Walker and Hadley cells in inhibiting the rising motions over the region in the months following April. [ABSTRACT FROM AUTHOR]

Copyright of Revista Brasileira de Engenharia Agricola e Ambiental - Agriambi is the property of Revista Brasileira de Engenharia Agricola e Ambiental and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Revista Brasileira de Engenharia Agricola e Ambiental - Agriambi is the property of Revista Brasileira de Engenharia Agricola e Ambiental and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Tabebuia impetiginosa is a tree of high economic, ornamental and medicinal value and is presently on the list of the Forest Institute of São Paulo as a species in need of genetic preservation ex situ. Thus, the objective of this research was to study the physiological performance of T. impetiginosa seeds with different moisture contents and storage in liquid nitrogen for 360 days. Mature fruits were placed under shade in the laboratory to allow hand seed extraction. The initial moisture content of the seed lot was then determined and a portion of it was removed that had the highest degree of moisture (treatment) to be studied, which was 18.3%. The remaining seeds were submitted to drying in a forced air circulation dryer at 30°C in order to obtain the other degrees of moisture (12.5, 8.4 and 4.2%). The seed portions corresponding to the four moisture contents were stored in liquid nitrogen (-196°C). They were submitted to physiological evaluations at 0, 120, 240 and 360 days of storage. The experiment was set up in a randomized complete design, with four treatments (moisture degrees) and four replications; means were compared by the Tukey test at 5%. T impetiginosa seeds can be previously dried to a low degree of moisture (4.2%) and preserved in liquid nitrogen for 360 days. [ABSTRACT FROM AUTHOR]

This study aims to analyze the atmospheric conditions associated with an event of intense precipitation caused by Easterly Wave Disturbances (EWDs), as well as the environmental conditions related to the mass gravitational movement that occurred between 14th June and 15th June of 2014, in the district of Mãe Luiza, Natal/RN/Brazil. The synoptic conditions, the vertical integrated moisture flux and the energetic behavior in the EWD's performance phases were analyzed. In addition to these factors, local environmental aspects were assessed, classifying the vulnerability to disaster events in the affected area. Over the days of the operation of the atmospheric system, the daily accumulation of precipitation was greater than 100 mm, with precipitation accumulated in 3 h in the order of 60 mm for the stages of maturation of the disturbance. The main synoptic conditions associated with EWDs were exhibited by the intense anomalies of wind speed and high humidity flux on the east coast of the Northeast, which intensified the influx of moisture into the continent over the period of the operation of the system. Conditions of high to very high vulnerability were identified in the area where the event took place and also in other expressive parts of the district. [ABSTRACT FROM AUTHOR]

Aim Relationships between elevation and litter-dweller harvestman (Arachnida: Opiliones) species richness along three elevational gradients in the Brazilian Atlantic Forest were evaluated. Specifically, three candidate explanatory factors for the observed patterns were tested: (1) the mid-domain effect, (2) the Rapoport effect, and (3) the influence of environmental variables on species density and specimen abundance. Location Cuscuzeiro, Corcovado and Capricórnio mountains, in Ubatuba (23°26′ S, 45°04′ W), a coastal municipality in São Paulo state, south-eastern Brazil. Methods We recorded harvestman species and abundance through active sampling using 8 × 8-m plots in both summer and winter. At each plot we measured the temperature, humidity and mean litter depth. Harvestman species richness per elevational band was the sum of all species recorded in each band, plus the species supposed to occur due to the interpolation of the upper and lower elevational records. Differences between observed and expected species richness per elevational band, based on the mid-domain effect, were examined through a Monte Carlo simulation. The Rapoport effect was evaluated using both the midpoint method and a new procedure proposed here, the ‘specimen method’. We applied multiple regression analysis to evaluate the contribution of each environmental variable (elevation, temperature, humidity and litter depth) on species density and specimen abundance per plot. Results Harvestman abundance and species richness decreased at higher elevations in the three mountains. The decrease in species richness was not monotonic and showed a plateau of high species richness at lower elevations. The number of harvestman species per elevational band does not fit that predicted by the mid-domain effect based solely on geometric constraints assuming hard boundaries. Species with their midpoints at higher elevations tended to cover broader elevational range sizes. Both the midpoint method and the specimen method detected evidence of the Rapoport effect in the data. At fine spatial scales, temperature and humidity had positive effects on species density and specimen abundance, while mean litter depth had no clear effect. These relationships, however, were not constant between seasons. Main conclusions Our results suggest that harvestman species density declines at higher elevations due to restrictions imposed by temperature and humidity. We found a pattern in species range distribution as predicted by the elevational Rapoport effect. However, the usual rescue effect proposed to explain the Rapoport effect does not apply in our study. Since the majority of harvestman species covering broader elevational ranges do not exhibit reduced abundance at low elevations, an alternative rescue effect is proposed here. According to this alternative rescue effect, the decrease in species richness at higher elevations occurs due to differential upper limits of species with source populations below mid-elevations. The seasonal differences in the relationships between environmental variables and species richness/specimen abundance per plot is an indication that species occurrence on elevational gradients is seasonally dependent. Thus relationships and hypotheses based on data recorded over short time periods, or in a single season, should be viewed cautiously. [ABSTRACT FROM AUTHOR]

Large year-to-year variations of δ18O were found in the precipitation recorded in the International Atomic Energy Agency/Global Network of Isotopes in Precipitation (IAEA/GNIP) database for February at Cuiabá, located on the northern fringe of Pantanal, Brazil. Three depleted years (1963, 1978, and 1968) and three enriched years (1966, 1984, and 1983) were chosen to investigate this phenomenon and to correlate the amount of precipitation, the occurrences of storm precipitation, and the vapor flux field. In the depleted years, precipitation exceeding the long-term mean was observed at Cuiabá, while the southward vapor flux from the Amazon basin was less than the long-term mean. Since d-excesses in these years were large in general, fast evaporation must contribute to the greater precipitation observed in these depleted years. In contrast, such common features were not found in the vapor flux field in the enriched years. The occurrences of storm precipitation are important in 1966, while the amount effect is responsible for 1984. In 1983, enriched meteoric water is attributed to both the occurrences of storm precipitation and vapor flux field. [ABSTRACT FROM AUTHOR]

The spatio-temporal variations of the water budget components in the Amazon region are investigated by using a combination of hydrometeorological observations and moisture fluxes derived from the NCEP/NCAR reanalyses, for the period 1970-1999. The key new finding of this study identifies the major differences in the water balance characteristics and variability between the northern and southern parts of the basin. Our results show that there is a seasonality and interannual variability of the water balance that varies across the basin. At interannual time scales, anomalies in the water balance components in the northern Amazon region show relatively stronger links with tropical Pacific interannual variability. Over the entire region, precipitation exceeds evaporation and the basin acts as a sink of moisture (P>E). However, on some occasions the basin can act as a source for moisture (P

Geomorphologic studies and palynological analysis of a core in the middle of Lagoa Santa, a lake in central Brazil (19°389S; 43°549W), have provided palaeoenvironmental information on the region and lake history during the Holocene. Prior to 5300 yr BP there is no pollen record in the sediments. The presence of spores of Lycopodium and algae (Phase I) between c. 6100 and 5400 yr BP indicate a gradual increase of moisture in the ancient valley. Between c. 5400 and c. 4600 yr BP the records of pollen, spores and algae indicate the presence of an intermittent marsh on the valley floor (Phase IIA) and a climate drier than at present; Gramineae pollen dominates the assemblages, followed by Compositae and Portulacaceae. At approximately 4600 yr BP pollen grains are abundant, percentage of arboreal pollen increases and Lycopodium spores are replaced by fern spores of a moist environment; the marsh was replaced by a permanent lake (Phase IIB). An ancient landslide scar was probably active shortly before this time and started to deposit debris at the basin outlet causing the formation of the permanent lake that has existed since then. A mosaic of forests and ‘cerrado’ (savannah-like vegetation) covered the region around the lake and the climate was warm semi-humid, similar to the present. The abundant archaeological sites dating from c. 5000 yr BP are coeval with the formation of the lake and of the change towards a more humid phase. From c. 3000 yr BP to the present, changes in the percentage of arboreal pollen indicate small oscillations in precipitation. The uppermost 20 cm of the sediment contains oxidized clay mixed with the lake sediment. Nevertheless, the well-preserved palynomorphs show that the oxidized material was transported to the lake as a result of human activities around the basin. The depletion of Stryphnodendron spp. trees in recent last centuries confirms human disturbance of the natural ecosystems. In general terms, the climatic variations detected at Lagoa Santa during the Holocene are in accordance with those in other parts of central Brazil. [ABSTRACT FROM AUTHOR]

Municipal Solid Waste (MSW) from the city of Boa Esperança, Minas Gerais, Brazil, was used to produce refuse-derived fuel (RDF). The MSW contains residues from human society, including product packaging, bottles, batteries, organic waste, fines, textiles, health textiles, plastics, glass, and metals, among others. The following protocol was performed during the conversion of MSW to RDF: (i) the raw MSW was placed in a silo and sent to a primary crusher using a metal conveyor belt, which reduced the particle size to 80 mm; (ii) the biomass was transferred to a selective waste collection platform by a rubber conveyor belt, and the recyclable waste, metals, and glasses were separated manually; (iii) residual metals were removed by a magnetic separator; (iv) the waste was transferred to a secondary crusher which reduced the particle size to 60 mm; (v) the waste passed through an airborne separator to remove materials with high density, such as glass, stones, and organic materials, using a metallic conveyor belt; (vi) the particle size was reduced to 40 mm by a tertiary crusher; (vii) the aluminium was separated from the non-metallic materials (plastic, paper, rubber, etc.) using an eddy current separator; (viii) the particle size was reduced to 25 mm using a quaternary crusher; (ix) the MSW was introduced into a rotary dryer using a metal conveyor belt, where the moisture content was reduced to close to 15 wt%, which required thermal energy equivalent to 186 kWh; (x) the RDF was used in a thermochemical reactor and 4148 kWh of thermal energy was produced. In addition, the MSW and RDF were analysed, and the elemental composition and combustion characteristics were determined. Based on these results, the protocol evaluated was found to be effective in the conversion of MSW to RDF, which can be used as a source of renewable fuel., (Copyright © 2019 Elsevier Ltd. All rights reserved.)