Landfill leachates are high-strength complex mixtures containing dissolved organic matter, ammonia, heavy metals, and sulfur species, among others. The problem of leachate treatment has subsisted for ...some time, but an efficient and cost-effective universal solution capable of ensuring environmental resources protection has not been found. Aerobic granular sludge (AGS) has been considered a promising technology for biological wastewater treatment in recent years. Granules’ layered structure, with an aerobic outer layer and an anaerobic/anoxic core, enables the presence of diverse microbial populations without the need for support media, allowing simultaneous removal of different pollutants in a single unit. Besides, its strong and compact arrangement provides higher tolerance to toxic pollutants and the ability to withstand large load fluctuations. Furthermore, its good that settling properties allow high biomass retention and better sludge separation. Nevertheless, AGS-related research has focused on carbon-nitrogen-phosphorus removal, mainly from sanitary sewage. This review aims to summarize and analyze the main findings and problems reported in the literature regarding AGS application to landfill leachate treatment and identify the knowledge gaps for future applications.
Refrigerated raw milk may contain psychrotrophic microorganisms that produce thermoresistant exoproteases and lipases, which may compromise the quality of processed fluid milk and dairy products ...during storage. The aim of this work was to quantify and identify the deteriorating psychrotrophic microbiota in Brazilian refrigerated raw milk using genetic diversity analysis. The mean psychrotrophic count was 1.1 × 104 cfu/mL. Of the total isolates, 47.8 and 29.8% showed deteriorating activity at 35°C within 48 h and 7°C within 10 d, respectively. Among the proteolytic species, more isolated by this study were Lactococcus lactis (27.3%), Enterobacter kobei (14.8%), Serratia ureilytica (8%), Aerococcus urinaeequi (6.8%), and Bacillus licheniformis (6.8%). Observed among lipolytics were E. kobei (17.7%), L. lactis (15.6%), A. urinaeequi (12.5%), and Acinetobacter lwoffii (9.4%). The isolates S. ureilytica, E. kobei, Pseudomonas spp., and Yersinia enterocolitica potentially produced alkaline metalloprotease (aprX). Despite the low counts, a considerable portion of the psychrotrophic microbiota presented spoilage potential, which reaffirms the need for rigor in the control of contamination and the importance of rapid processing as factors that maintain the quality of milk and dairy products.
This article reports the material evidence of roads in the northwestern Maya Lowlands that were in use from the Middle Preclassic (800–300 BC) through the Late Classic (AD 700–900) period in Chiapas ...and Tabasco, Mexico. The study includes archaeological evidence recovered from field research in an area covering approximately 670 km2 and 618 recorded archaeological sites. It presents the physical characteristics of a series of piedmont paths that connected the region from the Usumacinta River to the Tulijá River, including large population centers such as Palenque and Chinikihá. The study uses a geographic information system (GIS) least cost path (LCP) analysis to identify the location of roads and how they relate to regional settlement patterns. It also tests the use of modern computational models to advance regional studies in the Maya area. Study results show how the Classic Maya adapted and appropriated the region's topography to facilitate movement, long-term settlement, and the building of landesque capital.
We explore the possible connection between the open cluster IC 2391 and the unbound Argus association identified by the search for associations containing young stars survey. In addition to common ...kinematics and ages between these two systems, here we explore their chemical abundance patterns to confirm if the two substructures shared a common origin. We carry out a homogenous high-resolution elemental abundance study of eight confirmed members of IC 2391 as well as six members of the Argus association using UVES spectra. We derive spectroscopic stellar parameters and abundances for Fe, Na, Mg, Al, Si, Ca, Ti, Cr, Ni and Ba.
All stars in the open cluster and Argus association were found to share similar abundances with the scatter well within the uncertainties, where Fe/H = −0.04 ± 0.03 for cluster stars and Fe/H = −0.06 ± 0.05 for Argus stars. Effects of overionization/excitation were seen for stars cooler than roughly 5200 K as previously noted in the literature. Also, enhanced Ba abundances of around 0.6 dex were observed in both systems. The common ages, kinematics and chemical abundances strongly support the fact that the Argus association stars originated from the open cluster IC 2391. Simple modelling of this system finds this dissolution to be consistent with two-body interactions.
We examined the potential growth of clonal Eucalyptus plantations at eight locations across a 1000+ km gradient in Brazil by manipulating the supplies of nutrients and water, and altering the ...uniformity of tree sizes within plots. With no fertilization or irrigation, mean annual increments of stem wood were about 28% lower (16.2
Mg
ha
−1
yr
−1, about 33
m
3
ha
−1
yr
−1) than yields achieved with current operational rates of fertilization (22.6
Mg
ha
−1
yr
−1, about 46
m
3
ha
−1
yr
−1). Fertilization beyond current operational rates did not increase growth, whereas irrigation raised growth by about 30% (to 30.6
Mg
ha
−1
yr
−1, about 62
m
3
ha
−1
yr
−1). The potential biological productivity (current annual increment) of the plantations was about one-third greater than these values, if based only on the period after achieving full canopies. The biological potential productivity was even greater if based only on the full-canopy period during the wet season, indicating that the maximum biological productivity across the sites (with irrigation, during the wet season) would be about 42
Mg
ha
−1
yr
−1 (83
m
3
ha
−1
yr
−1). Stands with uniform structure (trees in plots planted in a single day) showed 13% greater growth than stands with higher heterogeneity of tree sizes (owing to a staggered planting time of up to 80 days). Higher water supply increased growth and also delayed by about 1 year the point where current annual increment and mean annual increment intersected, indicating opportunities for lengthening rotations for more productive treatments as well as the influence of year-to-year climate variations on optimal rotations periods. The growth response to treatments after canopy closure (mid-rotation) related well with full-rotation responses, offering an early opportunity for estimating whole-rotation yields. These results underscore the importance of resource supply, the efficiency of resource use, and stand uniformity in setting the bounds for productivity, and provide a baseline for evaluating the productivity achieved in operational plantations. The BEPP Project showed that water supply is the key resource determining levels of plantation productivity in Brazil. Future collaboration between scientists working on silviculture and genetics should lead to new insights on the mechanisms connecting water and growth, leading to improved matching of sites, clones, and silviculture.
•A lightweight mortar was promising by blending waste RHA into the mixture.•Strength activity index (SAI) was achieved to be 95% and 85% for 5% and 10% waste RHA mortar, respectively.•Improved ...sulfate, acid and alkaline exposure were found for 5%, 10%, and 20% waste RHA specimens.•Reduced thermal conductivity can be achieved by mortar with 20% waste RHA.
Effect of waste RHA, residual ash generated from rice husk fuelled brick kilns, on strength, durability and thermal performances of mortar was investigated. Cement in the mortar was replaced by 0%, 5%, 10%, and 20% of waste RHA. Compressive strength, bulk density, water absorption, porosity, sorption rate, sulfate, acid and alkaline resistance, thermal performance, and microstructural analysis of specimens were examined.
Bulk density of control (i.e. 0%) and 20% waste RHA mortar were 2033 kg/m 3 and 1821 kg/m 3, respectively, promising a lightweight mortar by blending waste RHA into the mixture. At 56 days, Strength activity index (SAI) was achieved to be 95% and 85% for 5% and 10% waste RHA mortar, respectively, indicating better compressive strength achievement with waste RHA added mortar. The expansion due to sulfate exposure was reduced by 54% and 70%, for 5% and 10% waste RHA mortar, respectively. Weight loss due to acid exposure was reduced by 45%, 40%, and 25% for 5%, 10%, and 20% waste RHA specimens, respectively. The weight loss due to alkaline exposures was reduced from 3.13% to 2.41% with rising waste RHA level from 0% to 5%. Mortar with 20% waste RHA had a higher temperature difference than the control mortar, indicating that RHA contributed to the reduced thermal conductivity. At 5% waste RHA sample, high counts of CSH was formed, micro-voids were filled, making it a dense structure, which is favorable to achieve improved strength and durability performances.
Aim: We investigated changes in dung beetle β-diversity components along a subtropical elevational gradient, to test whether turnover or nestedness-related processes drive the dissimilarity of ...assemblages at spatial and temporal scales. Location: An elevational gradient (200-1,600 m a.s.l.) of the Atlantic Forest in southern Brazil. Methods: We investigated the extent to which β-diversity varied along the elevational gradient (six elevations) at both spatial (among sites at different elevations) and temporal (different months at the same site) scales. We compared both the turnover and nestedness-related dissimilarity of species and genera using multiple-site or multiple-month measures and tested whether these measurements were different from random expectations. Results: A mid-elevation peak in species richness along the elevational gradient was observed, and the lowest richness occurred at the highest elevations. We found two different groups of species, lowland and highland species, with a mixing of groups at intermediate elevations. The turnover component of β-diversity was significantly higher for both spatial (i.e. elevational) and temporal changes in species composition. However, when the data for genera by site were considered, the elevational turnover value decreased in relative importance. Nestedness-related processes are more important for temporal dissimilarity patterns at higher elevation sites. Main conclusions: Spatial and temporal turnover of dung beetle species is the most important component of β-diversity along the elevational gradient. High-elevation assemblages are not subsets of assemblages that inhabit lower elevations, but this relationship ceases when β-diversity is measured at the generic level. Environmental changes across elevations may be the cause of the differential establishment of distinctive species, but these species typically belong to the same higher taxonomic rank. Conservation strategies should consider elevational gradients in case-specific scenarios as they may contain distinct species assemblages in lowlands vs. highlands.
Non-steroidal anti-inflammatory drugs are inhibitors of cyclooxygenase-2 (COX-2) that were developed in order to avoid the side effects of non-selective inhibitors of COX-1. Thus, the present study ...aims to identify new selective chemical entities for the COX-2 enzyme via molecular modeling approaches. The best pharmacophore model was used to identify compounds within the ZINC database. The molecular properties were determined and selected with Pearson's correlation for the construction of quantitative structure-activity relationship (QSAR) models to predict the biological activities of the compounds obtained with virtual screening. The pharmacokinetic/toxicological profiles of the compounds were determined, as well as the binding modes through molecular docking compared to commercial compounds (rofecoxib and celecoxib). The QSAR analysis showed a fit with R = 0.9617, R
= 0.9250, standard error of estimate (SEE) = 0.2238, and F = 46.2739, with the tetra-parametric regression model. After the analysis, only three promising inhibitors were selected,
,
, and
, with their predicted pIC
(-log IC
) values,
= 7.9484,
= 9.3458, and
= 9.5272. All candidates inhibitors complied with Lipinski's rule of five, which predicts a good oral availability and can be used in in vitro and in vivo tests in the zebrafish model in order to confirm the obtained in silico data.
Coral health is under threat throughout the world due to regional and global stressors. White plague disease (WP) is one of the most important threats affecting the major reef builder of the Abrolhos ...Bank in Brazil, the endemic coral Mussismilia braziliensis. We performed a metagenomic analysis of healthy and WP-affected M. braziliensis in order to determine the types of microbes associated with this coral species. We also optimized a protocol for DNA extraction from coral tissues. Our taxonomic analysis revealed Proteobacteria, Bacteroidetes, Firmicutes, Cyanobacteria, and Actinomycetes as the main groups in all healthy and WP-affected corals. Vibrionales, members of the Cytophaga—Flavobacterium—Bacteroides complex, Rickettsiales, and Neisseriales were more abundant in the WP-affected corals. Diseased corals also had more eukaryotic metagenomic sequences identified as Alveolata and Apicomplexa. Our results suggest that WP disease in M. braziliensis is caused by a polymicrobial consortium.
Floods cause severe damage to people as well as to properties. The same flood can cause different levels of damage to different households, but investigations into floods tend to be conducted on ...regional and national scales, thereby missing these local variations. It is therefore necessary to understand individual experiences of flood damage to implement effective flood management strategies on a local scale. The main objectives of this study were to develop a model that represents the relationship between socioeconomic conditions and flood damage at a local scale, and to understand the socioeconomic factors most closely tied to flood damage. The analysis is novel in that it considers not only the impact of flood characteristics, but also the impact of social, economic, and geographic factors on flood damage. This analysis derives from a quantitative modeling approach based on community responses, with the responses obtained through questionnaire surveys that consider four consecutive floods of differing severity. Path analysis was used to develop a model to represent the relationships between these factors. A randomly selected sample of 150 data points was used for model development, and nine random samples of 150 data points were used to validate the model. Results suggest that poor households, located in vulnerable, low‐lying areas near rivers, suffer the most from being exposed to frequent, severe floods. Further, the results show that the socioeconomic factors with the most significant bearing on flood damage are per capita income and geographic location of the household. The results can be represented as a cycle, showing that social, economic, geographic, and flood characteristics are interrelated in ways that influence flood damage. This empirical analysis highlights a need for local‐scale flood damage assessments, as offered in this article but seldom seen in other relevant literature. Our assessment was achieved by analyzing the impact of socioeconomic and geographic conditions and considering the relationship between flood characteristics and flood damage.
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