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1.
Behav Res Methods ; 2024 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-38195787

RESUMO

Stimuli predicting rewards are more likely to capture attention, even when they are not relevant to our current goals. Individual differences in value-modulated attentional capture (VMAC) have been associated with various psychopathological conditions in the scientific literature. However, the claim that this attentional bias can predict individual differences requires further exploration of the psychometric properties of the most common experimental paradigms. The current study replicated the VMAC effect in a large online sample (N = 182) and investigated the internal consistency, with a design that allowed us to measure the effect during learning (rewarded phase) and after acquisition, once feedback was omitted (unrewarded phase). Through the rewarded phase there was gradual increase of the VMAC effect, which did not decline significantly throughout the unrewarded phase. Furthermore, we conducted a reliability multiverse analysis for 288 different data preprocessing specifications across both phases. Specifications including more blocks in the analysis led to better reliability estimates in both phases, while specifications that removed more outliers also improved reliability, suggesting that specifications with more, but less noisy, trials led to better reliability estimates. Nevertheless, in most instances, especially those considering fewer blocks of trials, reliability estimates fell below the minimum recommended thresholds for research on individual differences. Given the present results, we encourage researchers working on VMAC to take into account reliability when designing studies aimed at capturing individual differences and provide recommendations to improve methodological practices.

2.
Span J Psychol ; 25: e1, 2022 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-35923152

RESUMO

The elaborated intrusion theory of desire proposes that craving is a cognitive motivational process involving intrusive thoughts. Changing the way we react to them, cognitive defusion (CD), should limit thought elaboration and craving. We induced chocolate craving in female chocolate cravers before CD (Study 1). A decrease in craving measured by a single-item scale, Visual Analogical Scale (VAS; p < .001, ηp2 = .449) and as a state, State Food Craving Questionnaire (FCQ-S; p = .029, ηp2 = .106) were found in the experimental group, while similar results were also found in group control. The reduction in craving (VAS) in group CD correlated negatively with chocolate consumption on a bogus taste test (r = -.439, p = .036), while the correlation was positive in the case of group control (r = .429, p = .047). Food craving as a trait, measured by the Trait Food Craving Questionnaire (FCQ-T), showed negative correlations with measures of CD and mindfulness skills (lowest r = -.313, p = .018). In Study 2 participants made use of a smartphone application implementing the CD procedure in real contexts whenever they experienced food craving. A corresponding decline in self-reported craving was found, as well as in consumption of the craved food (indulgence) compared with the control condition. Our findings indicate that CD may be a promising intervention for tackling the elaboration of intrusive thoughts and eating behavior in young female food cravers, both in a controlled laboratory environment after a cue-food exposure craving induction procedure, as well as responding to naturally occurring food cravings in real-life settings.


Assuntos
Fissura , Preferências Alimentares , Cognição , Ingestão de Alimentos/psicologia , Comportamento Alimentar/psicologia , Feminino , Preferências Alimentares/psicologia , Humanos , Inquéritos e Questionários
3.
Food Res Int ; 152: 110873, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-35181065

RESUMO

Measures of drinking and eating behaviors may be assessed both explicitly (e.g., sensory and quality judgments) and implicitly (e.g., Electroencephalography, EEG), although the relationship between the results of both approaches remains unclear and each might be differentially affected by acquired knowledge. The main aim of the present study was to determine the strength of the relationship between these measures in sensory and hedonic processing of beers depending on the degree of tasting expertise. Beer experts, experts in non-beer beverages or edibles, and non-expert consumers took part in a sensory analysis procedure where they rated beers in terms of their sensory attributes and general quality-visual, olfactory, and gustatory phases-as well as their global hedonic value while their brain activity was recorded. The results suggest that participants evaluated the sensory properties of the beers in a rather similar manner. However, during the gustatory phase, experts and general tasters differed in terms of the activation of brain areas related to memory processes, while general tasters and consumers differed in brain activation related to hedonic processing. The relationship between self-reported quality judgments and EEG activity - particularly in relation to recognition and working memory components - appeared to be stronger in experts in comparison with the other groups (lowest |r| = 0.67, p < .01). Although lower in number, significant relationships were also found in general tasters and consumers, primarily involving hedonic processing (lowest |r| = 0.58, p < .01) and recognition memory (lowest |r| = 0.57, p < .01) components. Moreover, those relationships differed significantly, mostly between experts and consumers (lowest |z| = 2.68, p < .01), in terms of the involvement of working memory components. Taken together, the results of this study suggest that beer experts have a more efficient pattern of gustatory processing and show a better fit between explicit (judgments) and implicit (EEG) measures of sensory and hedonic quality of beers.


Assuntos
Cerveja , Paladar , Cerveja/análise , Encéfalo , Humanos , Julgamento , Paladar/fisiologia
4.
Span. j. psychol ; 25: e1, enero 2022. tab, graf
Artigo em Inglês | IBECS | ID: ibc-207104

RESUMO

The elaborated intrusion theory of desire proposes that craving is a cognitive motivational process involving intrusive thoughts. Changing the way we react to them, cognitive defusion (CD), should limit thought elaboration and craving. We induced chocolate craving in female chocolate cravers before CD (Study 1). A decrease in craving measured by a single-item scale, Visual Analogical Scale (VAS; p < .001, ηp2 = .449) and as a state, State Food Craving Questionnaire (FCQ-S; p = .029, ηp2 = .106) were found in the experimental group, while similar results were also found in group control. The reduction in craving (VAS) in group CD correlated negatively with chocolate consumption on a bogus taste test (r = –.439, p = .036), while the correlation was positive in the case of group control (r = .429, p = .047). Food craving as a trait, measured by the Trait Food Craving Questionnaire (FCQ-T), showed negative correlations with measures of CD and mindfulness skills (lowest r = –.313, p = .018). In Study 2 participants made use of a smartphone application implementing the CD procedure in real contexts whenever they experienced food craving. A corresponding decline in self-reported craving was found, as well as in consumption of the craved food (indulgence) compared with the control condition. Our findings indicate that CD may be a promising intervention for tackling the elaboration of intrusive thoughts and eating behavior in young female food cravers, both in a controlled laboratory environment after a cue-food exposure craving induction procedure, as well as responding to naturally occurring food cravings in real-life settings. (AU)


Assuntos
Humanos , Cognição , 24439 , Preferências Alimentares/psicologia , Humanos , Fissura , Inquéritos e Questionários
5.
Molecules ; 26(20)2021 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-34684778

RESUMO

Biohydrometallurgy recovers metals through microbially mediated processes and has been traditionally applied for the extraction of base metals from low-grade sulfidic ores. New investigations explore its potential for other types of critical resources, such as rare earth elements. In recent times, the interest in rare earth elements (REEs) is growing due to of their applications in novel technologies and green economy. The use of biohydrometallurgy for extracting resources from waste streams is also gaining attention to support innovative mining and promote a circular economy. The increase in wastes containing REEs turns them into a valuable alternative source. Most REE ores and industrial residues do not contain sulfides, and bioleaching processes use autotrophic or heterotrophic microorganisms to generate acids that dissolve the metals. This review gathers information towards the recycling of REE-bearing wastes (fluorescent lamp powder, spent cracking catalysts, e-wastes, etc.) using a more sustainable and environmentally friendly technology that reduces the impact on the environment.


Assuntos
Resíduos Industriais/análise , Metalurgia/métodos , Metais Terras Raras/isolamento & purificação , Microbiologia Industrial/métodos , Mineração , Reciclagem/métodos
6.
Behav Processes ; 188: 104394, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33872755

RESUMO

Two experiments, using rats as the subjects, and flavour aversion learning with an injection of lithium chloride (LiCl) as the unconditioned stimulus (US), examined the effects of a context shift between phases of the procedure on the retardation of learning produced by preexposure to the US. Experiment 1 showed that the US-preexposure effect (the reduction in the size of the conditioned aversion) was not attenuated when the animals were given both preexposure to the US and the conditioning procedure in a novel context but received the test phase in a different context (the home cages). Experiment 2 showed that, after degrading the injection cues-illness association by interpolating saline injections between LiCl preexposures, the US-preexposure effect was attenuated when there was a context shift between preexposure and conditioning, but that the context shift was without effect when it occurred between conditioning and test. These results are consistent with the proposal that US preexposure obtained in this procedure has its effect by interfering with the formation of the target association; they provide no support for the suggestion that the effect depends on interference at the test stage.


Assuntos
Aprendizagem da Esquiva , Condicionamento Clássico , Animais , Condicionamento Operante , Sinais (Psicologia) , Cloreto de Lítio/farmacologia , Ratos , Paladar
7.
Q J Exp Psychol (Hove) ; 73(4): 537-554, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31590606

RESUMO

Two experiments were designed to study the role of emotional impulsiveness in action control and selection, involving healthy young women participants. In Experiment 1, the effects of both outcome devaluation and Pavlovian-to-instrumental transfer (PIT) were assessed on instrumental responding. In Experiment 2, we further explored the effect of outcome devaluation on outcome-specific PIT. The role of emotional impulsivity, specifically negative urgency (NU), was also evaluated in both experiments using a self-reported measure (UPPS-P scale, Spanish short version). Experiment 1 showed both outcome devaluation and outcome-specific PIT effects, which were positively inter-correlated and negatively correlated with scores in NU. Experiment 2 found an effect of outcome devaluation on outcome-specific PIT, which was negatively correlated with scores on NU. These results highlight the relevance of considering individual differences in affect-driven impulsivity, specifically NU, when addressing failures in action control and selection (proneness to habit). Moreover, these findings suggest that, at least with the procedure used in these experiments, outcome-specific PIT may be based on a goal-directed process that is under the participant's control.


Assuntos
Afeto/fisiologia , Condicionamento Clássico/fisiologia , Condicionamento Operante/fisiologia , Objetivos , Comportamento Impulsivo/fisiologia , Autocontrole , Transferência de Experiência/fisiologia , Adulto , Feminino , Humanos , Adulto Jovem
8.
Learn Behav ; 47(2): 177-186, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30421121

RESUMO

In two experiments, rats received pairings of an almond flavor (Experiments 1 and 2B) or a vanilla flavor (Experiment 2A) with sucrose. In each experiment, half of the rats received prior exposure to the flavor and half were exposed to water. Conditioned preference was then assessed through two-bottle, flavor versus water, choice tests. Latent inhibition (indicated by a weaker preference in pre-exposed subjects) was observed in the experiment using the vanilla flavor. However, facilitation (a stronger preference in pre-exposed subjects) instead of latent inhibition was evident with the almond flavor, both across acquisition trials and in the final choice test. These results indicate that, unlike most other paradigms of Pavlovian conditioning, conditioned stimulus pre-exposure in flavor preference learning may either facilitate or retard the acquisition (or the expression) of a conditioned flavor preference. We explore the proposal that the critical difference between the flavors lies in their hedonic values, with facilitation being more likely in a flavor that is initially disliked.


Assuntos
Condicionamento Clássico , Sinais (Psicologia) , Inibição Psicológica , Animais , Comportamento de Escolha , Preferências Alimentares , Masculino , Ratos
9.
Psicológica (Valencia, Ed. impr.) ; 39(1): 41-63, ene. 2018. tab, graf
Artigo em Inglês | IBECS | ID: ibc-175101

RESUMO

Previous research suggests that utilitarian decisions to moral dilemmas often stem from analytic, controlled cognitive processes. Furthermore, processing disfluency can trigger analytic thinking and improve performance on tasks that require logic and cognitive reflection. In the present study we investigated how processing fluency affects the readiness with which people give utilitarian responses to both personal and impersonal dilemmas. Participants were presented in two different experimental blocks with dilemmas written in both easy- (fluent) and hard-to-read (disfluent) fonts. We expected that dilemmas written in a disfluent font would be associated with more utilitarian responses. Results supported this prediction, albeit only when the disfluent dilemmas appeared first, showing that participants endorsed more utilitarian actions in the disfluent condition than in the fluent condition across dilemma types. These data suggest that increasing processing disfluency by manipulating the font affects decisions in the moral domain


Investigaciones previas sugieren que las decisiones utilitarias a dilemas morales a menudo tienen origen en procesos cognitivos controlados y analíticos. Se sabe además que el procesamiento disfluente puede inducir pensamiento analítico y mejorar la ejecución en tareas que requieren lógica y reflexión cognitiva. En este estudio se investigó cómo la fluencia de procesamiento afecta a la disponibilidad con la que se dan repuestas utilitarias a dilemas morales personales e impersonales. Se presentaron a los participantes dilemas escritos tanto en una letra fácil (fluent) como difícil de leer (disfluent) en dos bloques experimentales diferentes. Se esperaba encontrar una asociación entre este último tipo de dilemas y respuestas más utilitarias. Los resultados apoyaron esta predicción cuando los dilemas disfluent se presentaron en primer lugar, mostrando que los participantes subscribían más acciones utilitarias en la condición disfluent que en la fluent, tanto para dilemas personales como impersonales. Estos datos sugieren que incrementar la disfluencia de procesamiento manipulando el tipo de letra utilizado afecta a las decisiones en el ámbito moral


Assuntos
Humanos , Masculino , Feminino , Adolescente , Adulto Jovem , Adulto , Princípios Morais , Tomada de Decisões/ética , Função Executiva , Comportamento de Escolha , Estudantes/psicologia , Testes Psicológicos/estatística & dados numéricos , Análise e Desempenho de Tarefas , Resolução de Problemas
10.
Sci Total Environ ; 598: 856-866, 2017 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-28458203

RESUMO

The aim of this work was to demonstrate the feasibility of the application of biosorption in the treatment of metal polluted wastewaters through the development of several pilot plants to be implemented by the industry. The use as biosorbents of both the brown seaweed Fucus vesiculosus and a sugar beet pulp was investigated to remove heavy metal ions from a wastewater generated in an electroplating industry: Industrial Goñabe (Valladolid, Spain). Batch experiments were performed to study the effects of pH, contact time and initial metal concentration on metal biosorption. It was observed that the adsorption capacity of the biosorbents strongly depended on the pH, increasing as the pH rises from 2 to 5. The adsorption kinetic was studied using three models: pseudo first order, pseudo second order and Elovich models. The experimental data were fitted to Langmuir and Freundlich isotherm models and the brown alga F. vesiculosus showed higher metal uptake than the sugar beet pulp. The biomasses were also used for zinc removal in fixed-bed columns. The performance of the system was evaluated in different experimental conditions. The mixture of the two biomasses, the use of serial columns and the inverse flow can be interesting attempts to improve the biosorption process for large-scale applications.

11.
Dev Psychobiol ; 59(3): 348-356, 2017 04.
Artigo em Inglês | MEDLINE | ID: mdl-28294331

RESUMO

The present study evaluated context-dependent learning under an operant conditioning procedure in infant rats. Preweanling rats were trained in context A during postnatal days (PDs) 16 and 17 to learn an appetitive operant conditioning task, employing milk chocolate as appetitive reinforcer. On PD18 the operant response was extinguished in context A, or in an alternative context B. The change from context A to B between acquisition and extinction did not affect the number of responses during extinction, but slightly modified the shape of the extinction curve. On PD19, a renewal test conducted in context A clearly showed ABA-renewal of the extinguished operant response. These results add to the body of evidence indicating that infants are able to acquire and retain contextual information, and support the notion that extinction during this ontogenetic period involves new learning.


Assuntos
Comportamento Apetitivo/fisiologia , Condicionamento Operante/fisiologia , Extinção Psicológica/fisiologia , Fatores Etários , Animais , Feminino , Masculino , Ratos , Ratos Wistar
12.
J Exp Psychol Anim Learn Cogn ; 42(4): 380-390, 2016 10.
Artigo em Inglês | MEDLINE | ID: mdl-27732050

RESUMO

In 3 experiments rats experienced 2 flavors, each paired with sucrose, in order to establish a conditioned preference to each. One (flavor Fe) was then presented alone (an extinction procedure) prior to a choice test between Fe and the flavor that did not undergo extinction (Fne). Hungry rats showed a preference for Fne over Fe (Experiment 1A), but rats that were not food-deprived showed no effect of extinction when given a choice between Fe and Fne immediately after extinction (Experiment 1B) or after an interval in which reexposure to sucrose was given (Experiment 2). The extinction procedure was not without effect, however, as Fe was preferred over Fne after sucrose had been devalued by pairing with lithium chloride, and Fne was preferred over Fe after a procedure likely to enhance the value of the sucrose (Experiment 3). The explanations considered propose that preference conditioning establishes a range of associations between the flavor and the various properties of sucrose (its nutritional value, its taste, the hedonic reaction it evokes). It is suggested that the form of learning that mediates revaluation effects is sensitive to extinction whereas that responsible for performance on a consumption test is not. (PsycINFO Database Record


Assuntos
Condicionamento Psicológico , Preferências Alimentares , Paladar , Animais , Fome , Ratos , Percepção Gustatória
13.
IET Nanobiotechnol ; 9(5): 252-8, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26435277

RESUMO

This study focuses on the green synthesis of noble metal nanoparticles (silver (Ag) and platinum (Pt)) and how the size and shape of the nanoparticles produced can be controlled through changes in the initial pH value of the precursor solution. The nanoparticles were characterised by ultra-violet-visible spectroscopy, transmission electron microscopy and X-ray diffraction. This simple and environmentally friendly method allows the synthesis of diverse nanostructures in the absence of a surfactant or polymer to direct nanoparticle growth, and without externally adding seed crystallites. The antibacterial effects of Ag nanoparticles and catalytic properties of Pt nanoparticles were explored for future promising biotechnological approaches in different fields.


Assuntos
Biotecnologia/métodos , Citrus sinensis/química , Nanopartículas Metálicas/química , Extratos Vegetais/metabolismo , Platina/química , Prata/química , Aeromonas/efeitos dos fármacos , Antibacterianos/química , Antibacterianos/metabolismo , Antibacterianos/farmacologia , Viabilidade Microbiana/efeitos dos fármacos , Extratos Vegetais/química , Platina/metabolismo , Platina/farmacologia , Prata/metabolismo , Prata/farmacologia
14.
Span J Psychol ; 18: E61, 2015 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-26256035

RESUMO

An increasing body of research has investigated the effect of emotions on judgments concerning moral transgressions. Yet, few studies have controlled for arousal levels associated with the emotions. High arousal may affect moral processing by triggering attention to salient features of transgressions, independently of valence. Therefore previously documented differences in effects of negative and positive emotions may have been confounded by differences in arousal. We conducted two studies to shed light on this issue. In Study 1 we developed a questionnaire including vignettes selected on the basis of psychometrical properties (i.e., mean ratings of the actions and variability). This questionnaire was administered to participants in Study 2, after presenting them with selected pictures inducing different valence but equivalent levels of arousal. Negative pictures led to more severe moral judgments than neutral (p = .054, d = 0.60) and positive pictures (p = .002, d = 1.02), for vignettes that were not associated with extreme judgments. In contrast, positive pictures did not reliably affect judgments concerning such vignettes. These findings suggest that the observed effects of emotions cannot be accounted for by an increase in attention linked to the arousal which accompanies these emotions.


Assuntos
Nível de Alerta/fisiologia , Emoções/fisiologia , Julgamento/fisiologia , Princípios Morais , Adulto , Feminino , Humanos , Masculino , Reconhecimento Visual de Modelos/fisiologia , Adulto Jovem
15.
Learn Behav ; 43(4): 376-83, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26077443

RESUMO

In two experiments, rats received pairings of the flavor of almond with either fructose or maltodextrin, and the conditioned preference for almond was then tested. In each experiment, half of the rats had received prior exposure to almond on its own, and half had received no preexposure. In Experiment 1, in which the rats were hungry during the test, the preference was greater in the nonpreexposed subjects, both for those trained with fructose and those trained with maltodextrin; that is, latent inhibition was obtained with both reinforcers. In Experiment 2, in which the rats were not food deprived prior to the test, not only was there no latent inhibition with either of the reinforcers, but, for both, the preference was greater for preexposed than for nonpreexposed subjects. These results give no support to the proposal that different types of reinforcer generate different types of learning. They are, however, consistent with the proposal that different types of learning control behavior when a rat is hungry and when it is not, and that the form that generates the preference in the latter case is not susceptible to the latent inhibition effect.


Assuntos
Condicionamento Psicológico , Preferências Alimentares , Inibição Psicológica , Motivação , Reforço Psicológico , Paladar , Animais , Aromatizantes , Fome , Masculino , Ratos
16.
Span. j. psychol ; 18: e61.1-e61.9, 2015. tab, ilus
Artigo em Inglês | IBECS | ID: ibc-139725

RESUMO

An increasing body of research has investigated the effect of emotions on judgments concerning moral transgressions. Yet, few studies have controlled for arousal levels associated with the emotions. High arousal may affect moral processing by triggering attention to salient features of transgressions, independently of valence. Therefore previously documented differences in effects of negative and positive emotions may have been confounded by differences in arousal. We conducted two studies to shed light on this issue. In Study 1 we developed a questionnaire including vignettes selected on the basis of psychometrical properties (i.e., mean ratings of the actions and variability). This questionnaire was administered to participants in Study 2, after presenting them with selected pictures inducing different valence but equivalent levels of arousal. Negative pictures led to more severe moral judgments than neutral (p = .054, d = 0.60) and positive pictures (p = .002, d = 1.02), for vignettes that were not associated with extreme judgments. In contrast, positive pictures did not reliably affect judgments concerning such vignettes. These findings suggest that the observed effects of emotions cannot be accounted for by an increase in attention linked to the arousal which accompanies these emotions (AU)


No disponible


Assuntos
Adulto , Feminino , Humanos , Masculino , Emoções Manifestas , Moral , Escalas de Graduação Psiquiátrica Breve , Estudantes/psicologia , Agitação Psicomotora/psicologia , Inquéritos e Questionários , Análise de Variância
17.
Res Microbiol ; 165(9): 794-802, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25283724

RESUMO

Aeromonas hydrophila is a facultative anaerobe which, under conditions of oxygen depletion, uses Fe(III) as electron acceptor. A. hydrophila produces pili during growth with Fe(III). The study was focused on the characterization of the morphology, the electrical properties and the nature of the bacterial pili. Scanning electron microscopy and conductive-probe atomic force microscopy revealed the presence of filaments between cells and substrate and their conductive nature. Our results indicate that pili of A. hydrophila strain A might serve as biological nanowires, transferring electrons from the cell surface to the surface of Fe(III) oxides and, in addition, the possibility of playing a role in inter/intra species signaling. Quorum sensing (QS) is recognized as one of the main regulatory ways for extracellular polymeric substances (EPS) production and biofilm formation. We present evidence that nanowire formation can be regulated by addition of synthetic acyl-homoserine lactones (AHL). These conductive pili may be involved in various interactions, and their protein components might be usable in the future for biotechnological approaches in materials science.


Assuntos
Aeromonas hydrophila/fisiologia , Condutividade Elétrica , Microbiologia Ambiental , Nanofios/microbiologia , Acil-Butirolactonas/metabolismo , Aeromonas hydrophila/metabolismo , Aeromonas hydrophila/ultraestrutura , Compostos Férricos/metabolismo , Fímbrias Bacterianas/ultraestrutura , Microscopia de Força Atômica , Microscopia Eletrônica de Varredura , Percepção de Quorum
18.
Appetite ; 80: 161-7, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24845784

RESUMO

In Experiment 1 rats were given training in which a mixture of two flavors was paired with sucrose. This established a substantial preference for each of the flavors; however, when rats were given prior experience with just one of the flavors paired with sucrose, training with the compound produced only a weak preference for the other - an example of the blocking effect, well known in other associative learning paradigms. Both the palatable taste of sucrose and its nutrient properties contribute to its ability to reinforce preference acquisition. The role of these two forms of learning was examined in two further experiments in which the reinforcer used was fructose (which is considered to support preference learning because it is palatable but not through its nutrient properties) or maltodextrin (thought to support preference learning by way of its nutrient properties). In neither case was blocking observed. At the theoretical level, this outcome constitutes a challenge to the attempt to explain flavor-preference learning in terms of the standard principles of associative learning theory. Its implication at the level of application is that the potential of the blocking procedure as a technique for preventing the development of unwanted flavor preferences may be limited.


Assuntos
Preferências Alimentares/fisiologia , Percepção Gustatória/fisiologia , Paladar , Animais , Frutose/administração & dosagem , Masculino , Polissacarídeos/administração & dosagem , Ratos , Ratos Wistar , Reforço Psicológico , Sacarose/administração & dosagem
19.
Biofouling ; 30(4): 501-11, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24673176

RESUMO

The aim of this work was to investigate the production of extracellular polymeric substances (EPS) by Aeromonas hydrophila grown under anaerobic conditions. EPS composition was studied for planktonic cells, cells attached to carbon fibre supports using a soluble ferric iron source and cells grown with a solid ferric iron mineral (gossan). Conventional spectrophotometric methods, Fourier transform infrared (FTIR) and confocal laser scanning microscopy (CLSM) were used to determine the main components in the biofilm extracted from the cultures. The key EPS components were proteins, indicating their importance for electron transfer reactions. Carbohydrates were observed mostly on the mineral and contained terminal mannosyl and/or terminal glucose, fucose and N-acetylgalactosamine residues.


Assuntos
Aeromonas hydrophila/metabolismo , Polímeros/metabolismo , Biofilmes , Microscopia Confocal , Polímeros/análise , Polímeros/química , Espectroscopia de Infravermelho com Transformada de Fourier
20.
IET Nanobiotechnol ; 7(3): 109-16, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24028809

RESUMO

The increasing demand and limited natural resources of noble metals make its recovery from dilute industrial wastes attractive, especially when using environmentally friendly methods. Nowadays, the high impact that nanotechnology is having in both science and society offers new research possibilities. Gold and silver nanoparticles were biosynthesised by a simple method using different algae as reducing agent. The authors explored the application of dead algae in an eco-friendly procedure. The nanoparticle formation was followed by UV-vis absorption spectroscopy and transmission electron microscopy. The functional groups involved in the bioreduction were studied by Fourier transform infrared spectroscopy.


Assuntos
Chondrus/metabolismo , Nanopartículas Metálicas/química , Biomassa , Ouro/química , Química Verde , Concentração de Íons de Hidrogênio , Microscopia Eletrônica de Varredura , Microscopia Eletrônica de Transmissão , Prata/química , Espectrofotometria Ultravioleta , Espectroscopia de Infravermelho com Transformada de Fourier
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