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.     

Effects of physical exercise on musculoskeletal disorders,stress and quality of life in workers

Background. The effect of physical exercise in the workplace (PEW) on health promotion of workers is contradictory. Objective. To evaluate the effects of the PEW in musculoskeletal disorders (MSDs), perception of stress and quality of life in workers. Methods. The participants were divided into two groups: control group (n?=?46) including non-participant workers of the PEW program, and PEW group (n?=?50) including workers who regularly participate in the exercise program. All workers answered the Nordic general questionnaire, the perceived stress scale and the quality-of-life questionnaire. Results. The PEW group reported a lower prevalence of MSDs for the trunk in the last 7 days and 12 months (p?=?0.021 and p?=?0.001, respectively), and for the upper limbs in the last 12 months (p?=?0.001) compared with the control group. The results for the perception of stress and quality of life showed no significant differences between the groups. Conclusion. PEW is a potential method to reduce MSDs in workers, but it was not efficient in reducing stress levels or improving the quality of life of the workers.     

Sustainability indicators in the swine industry of the Brazilian State of Santa Catarina

In recent decades, there has been a growing concern about measuring and evaluating the results of intensive production practices, such as the mode of integration practiced on a large scale by agro-industries. The present study discusses the application and the results of a Sustainability Indicators System in the context of the swine industry in the Brazilian State of Santa Catarina. These indicators, focused on the level of sustainability maturity, can be used as a way to diagnose and compare the efficiency of the industry from a broader perspective. The research findings indicate that most of the pig farms that have been studied can be classified as “in search of sustainability or sustainable.” Nevertheless, there are differences among the dimensions and between the most ranked farms and the others which must be considered for a better design and application of public policies and company strategies toward an effective and balanced social, economic and environmental sustainability.     

Enhanced photocatalytic activity using GO/TiO<Subscript>2</Subscript> catalyst for the removal of DCA solutions

This work aimed to optimize high-performance photocatalysts based on graphene oxide/titanium dioxide (GO/TiO₂) nanocomposites for the effective degradation of aqueous pollutants. The catalytic activity was tested against the degradation of dichloroacetic acid (DCA), a by-product of disinfection processes that is present in many industrial wastewaters and effluents. GO/TiO₂ photocatalysts were prepared using three different methods, hydrothermal, solvothermal, and mechanical, and varying the GO/TiO₂ ratio in the range of 1 to 10%. Several techniques were applied to characterize the catalysts, and better coupling of GO and TiO₂ was observed in the thermally synthesized composites. Although the results obtained for DCA degradation showed a coupled influence of the composite preparation method and its composition, promising results were obtained with the photocatalysts compared to the limited activity of conventional TiO₂. In the best case, corresponding to the composite synthesized via hydrothermal method with 5% of GO/TiO₂ weight ratio, an enhancement of 2.5 times of the photocatalytic degradation yield of DCA was obtained compared to bare TiO₂, thus opening more efficient ways to promote the application of photocatalytic remediation technologies.     

Ovariectomy predisposes female rats to fine particulate matter exposure’s effects by altering metabolic,oxidative, pro-inflammatory,and heat-shock protein levels

Environmental Science and Pollution Research - The reduction of estrogen levels, as a result of menopause, is associated with the development of metabolic diseases caused by alterations in...     

Human milk contamination by nine organochlorine pesticide residues (OCPs)

Abstract

Organochlorine pesticides (OCPs) are widely used around the world as insecticides, herbicides, fungicides, nematicides, and rodenticides. Despite banned in Brazil, the usage remains occurring in many countries. The persistence and extreme mobility of OCPs contribute to the contamination of the environment and the human body. The OCPs bioaccumulation in adipose tissue triggers the excretion into human milk during breastfeeding. Hence, the present study determined eighteen OCPs residues in the breast milk of mothers from the Western Region of Bahia State, Brazil. Nine different residue species were found, including beta-Hexachlorocyclohexane (9.24?±?0.00?ng g^?1 fat), delta- Hexachlorocyclohexane (22.15?±?10.48?ng g^?1 fat), Heptachlor (58.08?±?74.13?ng g^?1 fat), Aldrin (142.65?±?50.65?ng g^?1 fat), Dieldrin (774.62?±?472.68?ng g^?1 fat), Endosulfan I (408.44?±?245.51?ng g^?1 fat), Dichloro-diphenyl-dichloro-ethylene (29.17?±?22.42?ng g^?1 fat), Dichloro-diphenyl-trichloro-ethane (28.87?±?0.00?ng g^?1 fat) and Methoxychlor (1699.67?±?797.43?ng g^?1 fat). The Methoxychlor presence in all samples may reveal a recent exposure, while Dieldrin and Endosulfan I analyses can point to distant past exposure.     

QuEChERS: a sample preparation for extraction of carbaryl from rat feces

Carbamate compounds are an important group of cholinesterase inhibitors. There is a need for creating awareness regarding the risks of the inadequate carbamate use in the residential areas due to potential adverse human effects. Carbaryl is a commonly used pesticide worldwide. A simple, fast, and high-throughput method was developed employing liquid chromatography with fluorescence detector to determine carbaryl residues in rat feces. The extraction was performed by using a rapid, easy, cheap, effective, reliable, and safe (QuEChERS) method, using acetonitrile as the extracting solvent. The parameters for the performance of the extraction method were optimized, such as ratio of mass of sample per volume of extraction solvent, QuEChERS content, and cleanup columns. Linear response was obtained for all calibration curves (solvent and matrix-matched) over the established concentration range (5–500 μg/L) with a correlation coefficients higher than 0.999. The achieved recovery was 97.9% with relative standard deviation values of 1.1% (n = 4) at 167 μg/kg fortified concentration level and the limits of detection and quantification were 27.7 and 92.3 µg/kg, respectively.     

Historical carbon fluxes in the expanding deforestation frontier of Southern Brazilian Amazonia (1985–2012)

In tropical areas, pioneer occupation fronts steer the rapid expansion of deforestation, contributing to carbon emissions. Up-to-date carbon emission estimates covering the long-term development of such frontiers depend on the availability of high spatial–temporal resolution data. In this paper, we provide a detailed assessment of carbon losses from deforestation and potential forest degradation from fragmentation for one expanding frontier in the Brazilian Amazon. We focused on one of the Amazonia’s hot-spots of forest loss, the BR-163 highway that connects the high productivity agricultural landscapes in Mato Grosso with the exporting harbors of the Amazon. We used multi-decadal (1984–2012) Landsat-based time series on forested and non-forested area in combination with a carbon book-keeping model. We show a 36% reduction in 1984s biomass carbon stocks, which led to the emission of 611.5 TgCO₂ between 1985 and 1998 (43.6 TgCO₂ year⁻¹) and 959.8 TgCO₂ over 1999–2012 (68.5 TgCO₂ year⁻¹). Overall, fragmentation-related carbon losses represented 1.88% of total emissions by 2012, with an increasing relevance since 2004. We compared the Brazilian Space Agency deforestation assessment (PRODES) with our data and found that small deforestation polygons not captured by PRODES had increasing importance on estimated deforestation carbon losses since 2000. The comparative analysis improved the understanding of data-source-related uncertainties on carbon estimates and indicated disagreement areas between datasets that could be subject of future research. Furthermore, spatially explicit, annual deforestation and emission estimates like the ones derived from this study are important for setting regional baselines for REDD+ or similar payment for ecosystem services frameworks.