Facile fabrication of hybrid titanium(IV) isopropoxide/pozzolan nanosheets (TnS-Pz) of high photocatalytic activity: characterization and application for Cr(VI) reduction in an aqueous solution

Environmental Science and Pollution Research - This paper presents the synthesis of a hybrid material through the use of natural pozzolan and titanium(IV) isopropoxide using the sol-gel method and...     

Baked Foams Based on Cassava Starch Coated with Polyvinyl Alcohol with a Higher Degree of Hydrolysis

The aims of this work were to produce trays based on cassava starch, coated with polyvinyl alcohol (PVA) with a higher degree of hydrolysis (98%), and to study the effects of the coating on the mechanical and water sorption properties of the trays. Two types of PVA were tested: SELVOL? 325 (degree of polymerization?=?1000–1500) and SELVOL? 107 (degree of polymerization?=?350–650). A decrease in the water absorption capacity of 50% was observed when the coated samples were compared with the control sample after 30 min of immersion in water. It was observed in both coated samples a reduction of the initial rate of water adsorption sorption and a decrease in hydrophilicity compared with the control sample. Tensile strength and elongation were increased with application of the coatings. The use of the two types of PVA resulted in materials with similar mechanical and water sorption properties.     

An evaluation of fishery co-management experience in an Amazonian black-water river (Unini River,Amazon, Brazil)

We evaluated the implementation of a fishing agreement, which was created by negotiation among all users of the resources as a co-management strategy because its definition was a result of meetings between all users of the resources. The fishing agreement was implemented in Unini River, a tributary of the right bank of Negro River. Our approach was based on the perception of the people who live in that area, called ribeirinhos. The management strategy was based on spatial distribution of the different types of fishing. We used two logistic regression models to identify the variables which are important to determine the previous concordance and satisfaction with the agreement. First, we analyzed the initial effort to implement the agreement. The variable that influenced the decision of support for the agreement and satisfaction with the results of agreement in both models was the distance from the interviewee’s residence to the sport fishing area. The results showed that the perception of improvement in well-being of the communities and structured social organization are crucial for the success of the co-management strategy.     

The effects of sport fishing growth on behavior of commercial fishermen in Balbina reservoir, Amazon, Brazil

An important alternative for sustainable use of tucunaré stocks and improvement in fishermen welfare in Balbina reservoir, Central Amazon, would be to train commercial fisherman to also become tourist guides for sport fishing. In this study, we modeled fishermen response to this question, in order to evaluate the acceptance of such an idea. Thus, we surveyed 47 fishermen, who currently comprise approximately 75% of the total fishermen population. This survey was implemented during December of 2001 and January of 2002. We used a probity analysis to run two models. The first model includes the variables: family size, school level, fishing time, residence time and boat ownership. On the other hand, the second model includes the number of children under and above eight years old but not the family size. Both models are significant and the most relevant variables are: fishing time (years of participation of fisherman is in the activity) and residence time (length of residency of particular fishermen live at the village nearby the reservoir).     

Correction to: Characterization of a fatty acid-binding protein from the Pacific oyster (Crassostrea gigas): pharmaceutical and toxicological implications

Environmental Science and Pollution Research - A Correction to this paper has been published: https://doi.org/10.1007/s11356-021-13135-x     

Assessment of groundwater quality in a region of endemic fluorosis in the northeast of Brazil

The aim of this study was to estimate the risk for caries and fluorosis in a desertification area, applying the calcium/fluoride concentration ratio of underground water and the quality of water in a selected geographical region. This study was performed in the municipality of São João do Rio do Peixe, located in the tropical semiarid lands of Brazil. A total of 111 groundwater samples were collected. Fluoride concentration varied from 0.11 to 9.33 mg/L. Thirty percent of all samples analyzed showed values above 1.5 mg/L, while 64 % were above the ideal limit of 0.7 mg/L. Mean calcium concentration was 47.6 mg/L, and 14.4 % of all samples presented values above the WHO acceptable limits. The proportional value of calcium/fluoride in water showed that only 12 % of the samples were suitable for dental caries prevention with minimal risk for dental fluorosis. Mapping of the fluoride distribution indicated that approximately 2,465 people could be affected by dental fluorosis and 1,057 people might be affected by skeletal fluorosis. It can be concluded that, in addition to fluoride, many water parameters were not suitable for the drinking water. Mapping out calcium/fluoride ratio may indicate areas of water suitability for caries control, whereas the fluoride concentration solely can indicate the areas with the risk for fluorosis. This approach can be relevant for health authorities for identifying communities where dental caries or dental fluorosis is prevalent.     

Characterization of a fatty acid-binding protein from the Pacific oyster (Crassostrea gigas): pharmaceutical and toxicological implications

Environmental Science and Pollution Research - Pharmaceuticals and their metabolites constitute a class of xenobiotics commonly found in aquatic environments which may cause toxic effects in...