The effects of the magnitude of reinforcement on the resistance to change of humans engaged in a computer task were examined in two experiments. In each, responding was disrupted by increasing the force requirement of the required response. In Experiment 1, the participants were exposed to a multiple variable-interval (VI) VI schedule of reinforcement.
View Article and Find Full Text PDFThe transition to renewable resources and bioprocesses is essential to address climate change and meet energy demands. Biorefineries offer a sustainable solution by valorising agro-industrial wastes, such as apple pomace, a by-product of the juice and cider industries. This study presents an efficient process to produce 5-hydroxymethylfurfural (HMF) derivatives using deep eutectic solvent (DES) and microwave-assisted heating.
View Article and Find Full Text PDFCrit Rev Biotechnol
June 2025
Resveratrol is an antioxidant abundant in plants like grapes and peanuts and has garnered significant attention for its potential therapeutic applications. This review explores its chemical attributes, stability, and solubility, influencing its diverse applications and bioavailability. Resveratrol's multifaceted therapeutic roles encompass: antioxidant, cardioprotective, anti-inflammatory, neuroprotective, anti-aging, and anticancer properties.
View Article and Find Full Text PDFThe microbial biosynthesis of the antioxidant compound resveratrol offers an eco-friendly and sustainable alternative to chemical synthesis or plant extraction. Here, we showed that Kluyveromyces marxianus strains produce p-coumaric acid, a key precursor of resveratrol, with higher titres achieved under increased agitation conditions. Through further strain engineering, resveratrol production was achieved using glucose, xylose, and/or ethanol as substrates.
View Article and Find Full Text PDFAntioxidants (Basel)
February 2024
The increasing world population means an increased demand for sustainable processes and products related to foods, particularly those with added health benefits. Plants can be an alternative source of nutritional and biofunctional ingredients. plants are an underexploited bioresource, currently prevalent in the Mediterranean Basin and western Asia.
View Article and Find Full Text PDFBiomass is one of the renewable resources with the greatest potential, not only because of the possibility of energy recovery but also because of its content in components of interest. In this context, the regions of Galicia and Portugal have large areas of land dedicated to forestry, agriculture and livestock, and the large amount of waste generated represents a cost for the producer. The importance of these facts has aroused great interest in society to focus its interest on improving the current situation while seeking a benefit, both environmental and economic, from existing resources.
View Article and Find Full Text PDFResveratrol, a natural organic polyhydroxyphenolic compound, has gained significant attention in the last years given its potential health benefits, including antioxidant, anti-cancer, and anti-inflammatory properties. It can be directly extracted from plants, vegetables, and related products and waste resources, but also chemically/enzymatically/microbially synthesized. However, certain process strategies have some limitations, such as high costs, reduced yield or high energy demand, thus implying significant environmental loads.
View Article and Find Full Text PDFBehavioral momentum theory (BMT) provides a theoretical and methodological framework for understanding how differentially maintained operant responding resists disruption. A common way to test operant resistance involves contingencies with suppressive effects, such as extinction or prefeeding. Other contingencies with known suppressive effects, such as response-cost procedures arranged as point-loss or increases in response force, remain untested as disruptive events within the BMT framework.
View Article and Find Full Text PDFResveratrol is an antioxidant with applications in the food and cosmetic industries. Its biosynthesis can side the hindrances of its extraction from plants. The dairy industry generates tonnes of lactose-rich wastes, which can be a carbon source.
View Article and Find Full Text PDFResveratrol is a phenolic compound with strong antioxidant activity, being promising for several applications in health, food, and cosmetics. It is generally extracted from plants or chemically synthesized, in both complex and not sustainable processes, but microbial biosynthesis of resveratrol can counter these drawbacks. In this work, resveratrol production by microbial biosynthesis from lignocellulosic materials was assessed.
View Article and Find Full Text PDFThe implementation of biorefineries for a cost-effective and sustainable production of energy and chemicals from renewable carbon sources plays a fundamental role in the transition to a circular economy. The US Department of Energy identified a group of key target compounds that can be produced from biorefinery carbohydrates. In 2010, this list was revised and included organic acids (lactic, succinic, levulinic and 3-hydroxypropionic acids), sugar alcohols (xylitol and sorbitol), furans and derivatives (hydroxymethylfurfural, furfural and furandicarboxylic acid), biohydrocarbons (isoprene), and glycerol and its derivatives.
View Article and Find Full Text PDFThe effects of different physical-effort requirements on behavioral resistance to change were examined with undergraduate students engaging in a computer task for points exchangeable for money. In Baseline, button pressing was maintained on a multiple variable interval (VI) 45-s VI 45-s schedule of reinforcement with two physical-effort requirements: 10 N in the Low-Effort Component and 50 N in the High-Effort Component. In Test, button pressing was disrupted by a multiple extinction (EXT) EXT schedule plus anagrams as a concurrent task for five participants.
View Article and Find Full Text PDFAppl Microbiol Biotechnol
January 2019
Acetic acid tolerance and xylose consumption are desirable traits for yeast strains used in industrial biotechnological processes. In this work, overexpression of a weak acid stress transcriptional activator encoded by the gene HAA1 and a phosphoribosyl pyrophosphate synthetase encoded by PRS3 in a recombinant industrial Saccharomyces cerevisiae strain containing a xylose metabolic pathway was evaluated in the presence of acetic acid in xylose- or glucose-containing media. HAA1 or PRS3 overexpression resulted in superior yeast growth and higher sugar consumption capacities in the presence of 4 g/L acetic acid, and a positive synergistic effect resulted from the simultaneous overexpression of both genes.
View Article and Find Full Text PDFIn this work, four robust yeast chassis isolated from industrial environments were engineered with the same xylose metabolic pathway. The recombinant strains were physiologically characterized in synthetic xylose and xylose-glucose medium, on non-detoxified hemicellulosic hydrolysates of fast-growing hardwoods (Eucalyptus and Paulownia) and agricultural residues (corn cob and wheat straw) and on Eucalyptus hydrolysate at different temperatures. Results show that the co-consumption of xylose-glucose was dependent on the yeast background.
View Article and Find Full Text PDFPharmacogn Mag
February 2015
The present study aimed at characterizing the oil extracted from Bertholletia excelsa H.B.K.
View Article and Find Full Text PDFBackground: Artistic Gymnastics is a sport where athletes are frequently fatigued. One element that might influence this aspect is carbohydrate, an important energy substrate for the muscles and the CNS. Our goal was to investigate the influence of fatigue over artistic gymnastics athlete's performance and the effects of a carbohydrate supplementation on their performance.
View Article and Find Full Text PDFProduction of alternative fuels, such as biodiesel, from transesterification of vegetable oil driven by heterogeneous catalysts is a promising alternative to fossil diesel. However, achieving a successful substitution for a new renewable fuel depends on several quality parameters. (1)H NMR spectroscopy was used to determine the amount of methyl esters, free glycerin and acid number in the transesterification of soybean oil with methanol in the presence of hydrotalcite-type catalyst to produce biodiesel.
View Article and Find Full Text PDFThe aim of this study was to evaluate the efficacy of allogeneic block grafts impregnated with autologous bone marrow in horizontal ridge augmentation therapy. Ten patients with severe ridge volume deficiency in the anterior maxilla were treated with horizontal ridge augmentation. The patients were randomized into two groups: Five patients, using two allogeneic block grafts, were in the control group, and five patients, using two allogeneic block grafts impregnated with autologous bone marrow, were in the test group.
View Article and Find Full Text PDFBioresour Technol
September 2011
The distillate produced by deodorization of palm oil (DDPO) is a waste that corresponds to 4% of the product formed in this process. DDPO is 83% free of fatty acids (FFA), making it a good material for biodiesel production. In this paper, a catalyst prepared from a waste material, Amazon flint kaolin, was used for the esterification of DDPO with methanol.
View Article and Find Full Text PDFPurpose: The aim of this study was to evaluate the potential of an autologous bone marrow graft in preserving the alveolar ridges following tooth extraction.
Materials: Thirteen patients requiring extractions of 30 upper anterior teeth were enrolled in this study. They were randomized into two groups: seven patients with 15 teeth to be extracted in the test group and six patients with 15 teeth to be extracted in the control group.
Dengue is a febrile illness caused by Flavivírus and mainly transmitted by the mosquito Aedes aegypiti which have been a serious epidemic in Rio de Janeiro. In most of cases it was a self limited disease. We report two cases of a serious and rare complication of this viral infection.
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