cometadata/datacite-titles-descriptions-related-identifiers huggingface dataset:
DOI: 10.6084/m9.figshare.9870713.v1
title: Restoration of abandoned subtropical highland grasslands in Brazil: mowing produces fast effects, but hay transfer does not

description: ABSTRACT Subtropical Campos Sulinos grasslands, in South Brazil, are among the most biodiverse grasslands of the world. As climatic conditions lead to high productivity, disturbance are critical to maintain their diversity. Long-term exclusion, on the other hand, leads to plant species losses and changes in composition. No studies on the restoration of these grasslands after abandonment exist to date. We tested combinations of restoration techniques with the aim of increasing plant diversity in an abandoned and species-poor grassland in the South Brazilian highland region. In a bi-factorial experiment, we tested the effects of two different frequencies of mowing and of hay transfer. Mowing reduced plant cover, vegetation height, and abundance of erect grasses and shrubs, and increased species richness, diversity (Shannon diversity index) and prostrate forb and grass cover. No differences were found between mowing frequencies. Hay transfer was not effective at reintroducing species. The results of the present study provide further evidence that the reintroduction of plants is a major challenge in the restoration of subtropical and tropical grasslands. The study shows that mowing is a fast way to increase plant diversity in Campos Sulinos after long periods of abandonment.
DOI: 10.6084/m9.figshare.9870698
title: The experience of community urban gardens: Social organization and food security

description: ABSTRACT Objective To characterize Salvador-Bahia community gardens, with regard to social organization, work, supply and access to food, in line with the concept of Food Security. Methods A cross-sectional, exploratory study was carried out involving information collection, identification and selection of community gardens. Seven community gardens were located, although only five participated, with data collected through the application of semi-structured questionnaires, used with 13 horticulturists. Results Most of the gardens (80.0%) were located in popular neighborhoods and had been in place for less than five years; they operated with no land legalization (80.0%), in assigned areas (80.0%) and without any technical support (100.0%). No social organization was available in most of the initiatives (60.0%). The greatest difficulties included: lack of funding (80.0%) and volunteers for work (80.0%), as well as water use restrictions (80.0%). The crops included different fruits and vegetables, for self-consumption (80.0%), donation (60.0%), and/or commercialization (40.0%). Horticulturists included women (50.0%) and men (50.0%), mean age 44.8 years, education between illiterates (25.0%) and upper level (37.5%), rural migrants (50.0%) and experienced farmers (62.5%). Positive aspects included the production and access to natural food and the pleasure of working with earth. Conclusion Insufficient policies limited technical support and financing were observed in this segment, although there were contributions to the generation of work opportunities, supply and access to food. The study showed a strong link between community gardens and strategies to promote Food and Nutrition Security.
DOI: 10.6084/m9.figshare.9870695
title: A Mathematical Model on the Immune System Role in Achieving Better Outcomes of Cancer Chemotherapy

description: ABSTRACT The incidence of neoplastic diseases shows that the search for more effective cancer treatments is still necessary. In addition to standard treatments such as chemo- and radiotherapy, new treatment modalities have been focused in recent advances in immunology. Since little has been discussed about the biological implications of chemotherapy with respect to its impact on the immune system and on the other normal, “healthy” cells, we devote the present mathematical modeling work to do so. First, we prove the invariance of the region where all state variables remain positive (i.e., the number of cancer cells, normal cells and immune cells, and also the amount of chemotherapy). Afterward, we analyze the model in terms of the linear stability of the system and establish a necessary and sufficient condition for the local stability of the cure equilibrium point. Moreover, we simulate some scenarios involving both the immune system and chemotherapy, showing that a reasonable treatment strategy occurs when these are combined suitably.
DOI: 10.6084/m9.figshare.9870692
title: Influence of Vegetation on the Outdoor-to-Indoor Mobile Radio Propagation in 700 MHz Band

description: Abstract Starting from outdoor transmission, crossing vegetation, the wideband and narrowband characterization of the indoor mobile radio channel in the 700 MHz band is obtained from experiments carried out in the indoor environment of the Engineering building at Fluminense Federal University, and from the processed data, respectively, the power-delay profiles obtained permitted to calculate the time dispersion parameters and the envelope of the signal permitted to adjust probability density functions to the signal variability, concluding about the influence of vegetation on those characteristics.
DOI: 10.6084/m9.figshare.9870698.v1
title: The experience of community urban gardens: Social organization and food security

description: ABSTRACT Objective To characterize Salvador-Bahia community gardens, with regard to social organization, work, supply and access to food, in line with the concept of Food Security. Methods A cross-sectional, exploratory study was carried out involving information collection, identification and selection of community gardens. Seven community gardens were located, although only five participated, with data collected through the application of semi-structured questionnaires, used with 13 horticulturists. Results Most of the gardens (80.0%) were located in popular neighborhoods and had been in place for less than five years; they operated with no land legalization (80.0%), in assigned areas (80.0%) and without any technical support (100.0%). No social organization was available in most of the initiatives (60.0%). The greatest difficulties included: lack of funding (80.0%) and volunteers for work (80.0%), as well as water use restrictions (80.0%). The crops included different fruits and vegetables, for self-consumption (80.0%), donation (60.0%), and/or commercialization (40.0%). Horticulturists included women (50.0%) and men (50.0%), mean age 44.8 years, education between illiterates (25.0%) and upper level (37.5%), rural migrants (50.0%) and experienced farmers (62.5%). Positive aspects included the production and access to natural food and the pleasure of working with earth. Conclusion Insufficient policies limited technical support and financing were observed in this segment, although there were contributions to the generation of work opportunities, supply and access to food. The study showed a strong link between community gardens and strategies to promote Food and Nutrition Security.
DOI: 10.6084/m9.figshare.9870701.v1
title: A Study of Chemical Composition and Enzymatic Hydrolysis of Solid Organic Waste from Agrosilvopastoral Systems

description: Agrosilvopastoral waste, regarding agriculture and agro-industry sectors, is pointed as a promising sustainable raw material for biofuels production, specially concerning exploitation of lignocellulosic organic residues for fermentable sugars and cellulosic ethanol output, being therefore necessary to investigate the potential of these substrates concerning chemical composition, since many of them were not reported yet in literature. Being so, this paper presents a study of chemical composition and enzymatic hydrolysis of wastes from the four main crops in Maranhão, Brazil (soy, cassava, rice and corn) which are usually underutilized or abandoned in the field. The results of enzymatic hydrolysis were satisfactory for both soy and particularly corn residues, which presented total reducing sugars (TRS) percentage greater than 50% in comparison with pure cellulose.
DOI: 10.6084/m9.figshare.9870683
title: Influence of interphases on the effective thermal conductivity of periodic fiber-reinforced composites

description: ABSTRACT Composite materials commonly present thin regions or interphases located between the matrix and inclusions. These interphases influence the effective behavior of the composite. In many applications, composite materials are submitted to significant temperature variations and, consequently, the effective thermal conductivity of these materials becomes essential to understand their behavior. The purpose of this paper is to determine the influence of interphases on the effective thermal conductivity of periodic fiber reinforced composites, by using the parametric finite-volume theory. To this end, the effects of the thickness and thermal conductivity of the interphase are evaluated, as well as the fiber radius and its volumetric fraction. Composites with natural fibers are included in the analyzed examples. The results obtained with finite-volume theory are compared with other results found by numerical methods or experiments. Thus, it is noted that the interphase has a more pronounced influence on the composite effective thermal conductivity for larger fiber volume fraction and smaller fiber radius. The larger the interphase thickness, more its properties influence the effective thermal conductivity, when the fiber volume fraction is fixed. In conclusion, the interphase effects on the behavior of composite materials are extremely important and, consequently, they need to be considered to allow consistent and realistic predictions.
DOI: 10.6084/m9.figshare.9870689
title: Evaluation of the effect of compatibilizing agent (PP-g-MA) on PP/Thermoplastic starch blends

description: ABSTRACT The growing waste of plastics in the environment coupled with concerns about future oil shortages has increased interest in biodegradable polymers such as starch. In recent years, starch has been used in blends with different synthetic polymers. Such blends have been compatibilized by the use of compatibilizing agents of the copolymer type. In this study, the morphological, mechanical and thermal properties of polypropylene (PP)/thermoplastic starch (TPS) blends obtained in the presence of the compatibilizing agent (PP-g-MA) were evaluated. The thermoplastic starch was obtained in a single screw extruder with 20% (mass/mass) of glycerol used as plasticizer. PP/TPS blends were prepared by melt mixing in a co-rotating twin-screw extruder. The concentration of the compatibilizing agent was 3, 5 and 7% (mass/mass). The morphology of the blends was evaluated by scanning electron microscopy. The results showed a significant reduction of the dispersed starch phase with the addition of the PP-g-MA. The blends obtained in the presence of PP-g-MA showed a more homogeneous distribution of the starch phase in the PP matrix. The results obtained with the tensile tests showed that the elastic modulus of PP undergoes a slight increase with the addition of the starch and the compatibilizer. The tensile strength of the PP was not significantly affected. However, there was a significant decrease of the elongation at break with the incorporation of starch. The starch incorporated in the PP matrix led to a significant increase in the impact strength of the final material. However, with the addition of PP-g-MA to the PP/TPS blend, the impact strength falls. This result can be attributed to the reduction of the starch phase in the PP matrix. The thermal stability of the PP/TPS blends was slightly increased with the incorporation of the compatibilizing agent. The materials obtained can be used instead of PP.
DOI: 10.6084/m9.figshare.9870695.v1
title: A Mathematical Model on the Immune System Role in Achieving Better Outcomes of Cancer Chemotherapy

description: ABSTRACT The incidence of neoplastic diseases shows that the search for more effective cancer treatments is still necessary. In addition to standard treatments such as chemo- and radiotherapy, new treatment modalities have been focused in recent advances in immunology. Since little has been discussed about the biological implications of chemotherapy with respect to its impact on the immune system and on the other normal, “healthy” cells, we devote the present mathematical modeling work to do so. First, we prove the invariance of the region where all state variables remain positive (i.e., the number of cancer cells, normal cells and immune cells, and also the amount of chemotherapy). Afterward, we analyze the model in terms of the linear stability of the system and establish a necessary and sufficient condition for the local stability of the cure equilibrium point. Moreover, we simulate some scenarios involving both the immune system and chemotherapy, showing that a reasonable treatment strategy occurs when these are combined suitably.
DOI: 10.6084/m9.figshare.9870680
title: Evaluating the chemical composition and antioxidant activity of three Egyptian seaweeds: Dictyota dichotoma, Turbinaria decurrens, and Laurencia obtusa

description: Abstract Seaweeds have a growing number of successful applications in the food industry, medicine and in the cosmetic industry, which increases the importance of evaluating their chemical composition. In the present study, three common Egyptian seaweeds (Dictyota dichotoma, Turbinaria decurrens and Laurencia obtusa) were collected from the Red Sea coast, Suez, Egypt. The chemical profile of the three seaweeds was studied beside the antioxidant activity of their extracts. The results indicated that the amount of carbohydrate was greater than the protein and lipid contents in the three seaweeds, with a natural richness in minerals and antioxidants besides considerable amounts of monounsaturated and polyunsaturated fatty acids, including Omega-3 and Omega-6 fatty acids. All essential amino acids for human were found in the three seaweeds, with significant amounts of aspartic and glutamic acids. Furthermore, the results of the antioxidant activity assays were consistent with the antioxidant contents (phenols, flavonoids, alkaloids, vitamin C, carotenoids) of each seaweed. D. dichotoma was the most valuable seaweed of the three species studied, due to its relatively high protein content of 7.28 ± 0.25%, moderate carbohydrate content of 25.35 ± 0.32%, and highest pigment and antioxidant contents. In conclusion, these three seaweeds, especially Dictyota dichotoma, have an interesting chemical composition with a prospective nutritional and pharmaceutical value.
DOI: 10.6084/m9.figshare.9870686
title: Study of osmotic dehydration of kiwi fruit using sucrose solution

description: Abstract Osmotic dehydration of kiwi was evaluated using 45, 55 and 65 °Brix sucrose solutions. Free moisture, water activity and solutes gain decreased in fruit during the process. Water loss rates were higher in the beginning of drying. Water activity decrease was higher when the product was in 65 °Brix solution. The equilibrium moisture content estimated by the Peleg model decreased significantly with increasing concentration of the osmotic solution, and the diffusivity values of water loss were in the range from 1.5 × 10-9 to 1.9 × 10-9 m2 s-1. The osmotic pressures of the solutions were also predicted.
DOI: 10.6084/m9.figshare.9870692.v1
title: Influence of Vegetation on the Outdoor-to-Indoor Mobile Radio Propagation in 700 MHz Band

description: Abstract Starting from outdoor transmission, crossing vegetation, the wideband and narrowband characterization of the indoor mobile radio channel in the 700 MHz band is obtained from experiments carried out in the indoor environment of the Engineering building at Fluminense Federal University, and from the processed data, respectively, the power-delay profiles obtained permitted to calculate the time dispersion parameters and the envelope of the signal permitted to adjust probability density functions to the signal variability, concluding about the influence of vegetation on those characteristics.
DOI: 10.6084/m9.figshare.9870677
title: Evaluation of different factors in the removal of remazol brilliant blue from aqueous solutions by adsorption in sugarcane and green coconut fibers

description: ABSTRACT The textile industries, during the dyeing process, release a large amount of dyes in the water. In addition to its visual effect and its adverse impacts on photosynthesis and chemical oxygen demand, many synthetic dyes are toxic, recalcitrant, mutagenic and carcinogenic. In this way, new alternatives of treatment of the generated effluents, less aggressive to the environment, of low cost and renewable have been sought, as the use of lignocellulosic agricultural residues, like dyes adsorbents. In this study, sugar cane and coconut fibers were studied for their ability to adsorb Remazol Brilliant Blue BB dye, and the effects of time, pH, amount of adsorbent material and dye concentration on dye adsorption were investigated. The optimal adsorption time was 24 h for coconut fiber and 12 h for sugar cane fiber. For both fibers, the optimal pH for the adsorption of dye was 2, and the use of 20 g L-1 of fiber was the most effective for removing 50-200 mg L-1 of Remazol Brilliant Blue BB, with adsorption percentages of above 90.50% observed for both fibers.
DOI: 10.6084/m9.figshare.9870683.v1
title: Influence of interphases on the effective thermal conductivity of periodic fiber-reinforced composites

description: ABSTRACT Composite materials commonly present thin regions or interphases located between the matrix and inclusions. These interphases influence the effective behavior of the composite. In many applications, composite materials are submitted to significant temperature variations and, consequently, the effective thermal conductivity of these materials becomes essential to understand their behavior. The purpose of this paper is to determine the influence of interphases on the effective thermal conductivity of periodic fiber reinforced composites, by using the parametric finite-volume theory. To this end, the effects of the thickness and thermal conductivity of the interphase are evaluated, as well as the fiber radius and its volumetric fraction. Composites with natural fibers are included in the analyzed examples. The results obtained with finite-volume theory are compared with other results found by numerical methods or experiments. Thus, it is noted that the interphase has a more pronounced influence on the composite effective thermal conductivity for larger fiber volume fraction and smaller fiber radius. The larger the interphase thickness, more its properties influence the effective thermal conductivity, when the fiber volume fraction is fixed. In conclusion, the interphase effects on the behavior of composite materials are extremely important and, consequently, they need to be considered to allow consistent and realistic predictions.
DOI: 10.6084/m9.figshare.9870686.v1
title: Study of osmotic dehydration of kiwi fruit using sucrose solution

description: Abstract Osmotic dehydration of kiwi was evaluated using 45, 55 and 65 °Brix sucrose solutions. Free moisture, water activity and solutes gain decreased in fruit during the process. Water loss rates were higher in the beginning of drying. Water activity decrease was higher when the product was in 65 °Brix solution. The equilibrium moisture content estimated by the Peleg model decreased significantly with increasing concentration of the osmotic solution, and the diffusivity values of water loss were in the range from 1.5 × 10-9 to 1.9 × 10-9 m2 s-1. The osmotic pressures of the solutions were also predicted.
DOI: 10.6084/m9.figshare.9870671
title: Evaluation of the post cure use on the thermal and mechanical properties of a room temperature curing epoxy system

description: ABSTRACT In this work, a room temperature curing epoxy system was submitted to post cure cycles to evaluate the thermal and mechanical properties of the material. The samples were obtained by casting into a metallic tool and the post cure cycles were performed at 75°C, 90°C, 110°C for one hour and at 110°C cycle for 2 hours. The differential scanning calorimetry (DSC) results showed that the glass transition temperature of the material have not change significantly with the post cure cycles, which indicates a number of molecular crosslinks very similar to the original sample, without post cure. The thermogravimetric (TGA) results revealed a stepwise thermal degradation; where about 70% mass of the material undergoes thermal degradation in the temperature range from 330.9°C to 345.1°C. The temperature-time transformation (TTT) diagram of a thermoset polymer was used to understand the cure kinetics, where it was suggested that the amount of resin and curing agent had a more significant influence on the full curing of the sample than the post cure cycles carried out in this article. By means of mechanical properties, the hardness of the material remained unchanged with the post curing cycles. Only one batch obtained lower values of hardness because the excess of curing agent worked as plasticizing agent. O In terms of elastic modulus, the free-beam method presented values between 1.72GPa and 2.18GPa, and the post cure cycles did not have any notable influence on this property.
DOI: 10.6084/m9.figshare.9870680.v1
title: Evaluating the chemical composition and antioxidant activity of three Egyptian seaweeds: Dictyota dichotoma, Turbinaria decurrens, and Laurencia obtusa

description: Abstract Seaweeds have a growing number of successful applications in the food industry, medicine and in the cosmetic industry, which increases the importance of evaluating their chemical composition. In the present study, three common Egyptian seaweeds (Dictyota dichotoma, Turbinaria decurrens and Laurencia obtusa) were collected from the Red Sea coast, Suez, Egypt. The chemical profile of the three seaweeds was studied beside the antioxidant activity of their extracts. The results indicated that the amount of carbohydrate was greater than the protein and lipid contents in the three seaweeds, with a natural richness in minerals and antioxidants besides considerable amounts of monounsaturated and polyunsaturated fatty acids, including Omega-3 and Omega-6 fatty acids. All essential amino acids for human were found in the three seaweeds, with significant amounts of aspartic and glutamic acids. Furthermore, the results of the antioxidant activity assays were consistent with the antioxidant contents (phenols, flavonoids, alkaloids, vitamin C, carotenoids) of each seaweed. D. dichotoma was the most valuable seaweed of the three species studied, due to its relatively high protein content of 7.28 ± 0.25%, moderate carbohydrate content of 25.35 ± 0.32%, and highest pigment and antioxidant contents. In conclusion, these three seaweeds, especially Dictyota dichotoma, have an interesting chemical composition with a prospective nutritional and pharmaceutical value.