Statistical accuracy for estimations of large wood blockage in a reservoir environment

Environmental Fluid Mechanics - The blockage of weirs or bridges by in-stream wood can reduce the flood discharge capacity, leading to hazardous situations. To assess the related risk, blocking...     

The methylic versus the ethylic route: considerations about the sustainability of Brazilian biodiesel production

Brazil is considered one of the world’s leading producers of biofuels given the predominance of ethanol fuel in its energy matrix. However, despite the prominence of Brazil in ethanol production, the vast majority of biodiesel production plants in Brazil use methanol instead of ethanol as the alcohol for transesterification reaction, as is generally the case in the rest of the world. The aim of this paper is therefore to examine the transesterification process in the Brazilian biodiesel production in terms of sustainability. In this regard, it was necessary to evaluate the way in which the industrial process is currently carried out, the role of government incentives or subsidies for the use of ethanol to produce biodiesel, and the investments of companies in technology development for the same purpose. This study presents indications that the development of the biodiesel market in Brazil is still oriented toward a production model which is inconsistent with the environmental and social aspects of sustainability.     

Modeling a spatially restricted distribution in the Neotropics: How the size of calibration area affects the performance of five presence-only methods

We here examine species distribution models for a Neotropical anuran restricted to ombrophilous areas in the Brazilian Atlantic Forest hotspot. We extend the known occurrence for the treefrog Hypsiboas bischoffi (Anura: Hylidae) through GPS field surveys and use five modeling methods (BIOCLIM, DOMAIN, OM-GARP, SVM, and MAXENT) and selected bioclimatic and topographic variables to model the species distribution. Models were first trained using two calibration areas: the Brazilian Atlantic Forest (BAF) and the whole of South America (SA). All modeling methods showed good levels of predictive power and accuracy with mean AUC ranging from 0.77 (BIOCLIM/BAF) to 0.99 (MAXENT/SA). MAXENT and SVM were the most accurate presence-only methods among those tested here. All but the SVM models calibrated with SA predicted larger distribution areas when compared to models calibrated in BAF. OM-GARP dramatically overpredicted the species distribution for the model calibrated in SA, with a predicted area around 10⁶ km² larger than predicted by other SDMs. With increased calibration area (and environmental space), OM-GARP predictions followed changes in the environmental space associated with the increased calibration area, while MAXENT models were more consistent across calibration areas. MAXENT was the only method that retrieved consistent predictions across calibration areas, while allowing for some overprediction, a result that may be relevant for modeling the distribution of other spatially restricted organisms.     

Dimethoate induces genotoxicity as a result of oxidative stress: in vivo and in vitro studies

Environmental Science and Pollution Research - Dimethoate ([O,O-dimethyl S-(N-methylcarbamoylmethyl) phosphorodithioate]) is an organophosphate insecticide and acaricide widely used for...     

Steel mill waste application in soil: dynamics of potentially toxic elements in rice and health risk perspectives

Environmental Science and Pollution Research - Potentially toxic elements (PTEs) are of great concern in steel mill wastes. Therefore, in order to use them as potential fertilizers in soil, risk...     

Can the environmental health of urban centers be assessed through pollutants trapped in lakes? A study case in the biggest city of the southern hemisphere

Environmental Science and Pollution Research - Air and water quality in urban centers are summited to pollution from different sources, such as industrial activities, traffic, and wastewater...     

Magnetic photocatalysts from δ-FeOOH and TiO2 and application in reactions for degradation of methylene blue and paracetamol with UV-C and sunlight

Environmental Science and Pollution Research - Water contamination is a common problem, especially considering dyes and drugs disposal. A possible and effective treatment method to remove these...     

Hydrocarbon biodegradation and dynamic laser speckle for detecting chemotactic responses at low bacterial concentration

We report on the biodegradation of pure hydrocarbons and chemotaxis towards these compounds by an isolated chlorophenol degrader,Pseudomonas strain H.The biochemical and phylogenetic analysis of the 16S rDNA sequence identified Pseudomonas strain H as having 99.56% similarity with P.aeruginosa PA01.This strain was able to degrade n-hexadecane,1-undecene,1-nonene,1-decene,1-dodecene and kerosene.It grew in the presence of 1-octene,while this hydrocarbons is toxic to other hydrocarbons degraders.Pseudomonas strain H was also chemotactic towards n-hexadecane,kerosene,1-undecene and 1-dodecene.These results show that this Pseudomonas strain H is an attractive candidate for hydrocarbon-containing wastewater bioremediation in controlled environments.Since the classical standard techniques for detecting chemotaxis are not efficient at low bacterial concentrations,we demonstrate the use of the dynamic speckle laser method,which is simple and inexpensive,to confirm bacterial chemotaxis at low cell concentrations (less than 105 colony-forming unit per millilitre (CFU/mL)) when hydrocarbons are the attractants.     

Parasitoid-induced mortality of Araneus omnicolor (Araneae, Araneidae) by Hymenoepimecis sp. (Hymenoptera, Ichneumonidae) in southeastern Brazil

All species included in the Polysphincta genus-group develop as ectophagous parasitoids of active spiders, killing their hosts prior to pupation. However, little information regarding natural history and ovipositing behavior of most species are available. In this study we inspected 85 webs of Araneus omnicolor to evaluate the frequency of parasitism and host size preferences of the wasp Hymenoepimecis sp. We also described the web characteristics of normal and parasitized spiders and the wasp ovipositing behavior. About 41% of the adult females of A. omnicolor inspected were parasitized. The highest incidence of parasitism was observed among relatively small females while no egg or larva was found in large individuals. Araneus omnicolor builds a strong web composed of an orb and barrier threads, where the spider rests within a curled leaf. The parasitoid larva builds its cocoon within this refuge, and modified cocoon webs were not observed. The ovipositing behavior of Hymenoepimecis sp. was very similar to that of Hymenoepimecis argyraphaga parasitizing Leucauge argyra, including the position of the sting, the killing of a previously attached larva, and the expelling of the egg from the base of the ovipositor.     

Recycling of FRP composites: reusing fine GFRP waste in concrete mixtures

Fibre reinforced polymer (FRP) materials are being increasingly used in several applications, but especially in the construction and transportation industries. The composites industry is now producing a wide range of FRP products that include strengthening strips and sheets, reinforcing bars, structural profiles, sandwich panels, moulded planks and piping. The waste management of FRP materials, in particular those made with thermosetting resins, is a critical issue for the composites industry because these materials cannot be reprocessed. Therefore, most thermosetting FRP waste is presently sent to landfill, in spite of the significant environmental impact caused by disposing of it in this way. Because more and more waste is being produced throughout the life cycle of FRPs, innovative solutions are needed to manage it. This paper first presents a state-of-the-art review of the present alternatives available to manage FRP waste. It then describes an experimental study conducted on the technical feasibility of incorporating the fine waste generated during the manufacturing of glass fibre reinforced polymer (GFRP) composites in concrete mixtures. Tests were carried out to evaluate the fresh-state and hardened-state properties of concrete mixes in which between 0% and 20% of sand was replaced by GFRP fine waste. Although the incorporation of high proportions of GFRP waste was found to worsen concrete performance in terms of both mechanical and durability-related properties, it seems feasible to incorporate low proportions and reuse GFRP fine waste in concrete, particularly in non-structural applications such as architectural concrete or pavement slabs, where good mechanical properties are less important.