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1.
Artículo en Inglés | MEDLINE | ID: mdl-35312189

RESUMEN

BACKGROUND: Over recent decades, chronic stress at an early age has become a worrying health problem in children. We seek to evaluate an intervention involving mindfulness-based practices and prosocial activities in 7- to 8-year-old children. METHODS: Stress levels were determined using hair cortisol concentration (HCC), and social integration was measured by means of a sociogram. The program had previously proven to be effective in decreasing salivary cortisol levels and in favouring social integration in children. A total of 35 children participated in the study: 18 constituted the intervention group and 17 the wait-list group. In both groups, HCC and social integration were evaluated before and after the intervention conducted throughout an entire school year. RESULTS: The experimental group showed a significant reduction in HCC, as well as significant enhancement of social integration levels, whereas no changes were observed in the wait-list group. CONCLUSIONS: This is the first research to show that HCC, a reliable neuroendocrine indicator, decreased as a result of a mindfulness-based program. This successful outcome adds new evidence to previous findings regarding the reduction of chronic stress in children following participation in this program.

2.
Sci Total Environ ; 830: 154629, 2022 Mar 22.
Artículo en Inglés | MEDLINE | ID: mdl-35337861

RESUMEN

Undaria pinnatifida is a brown algae native to Asia that has settled in various regions worldwide, periodically contributing with large quantities of C and nutrients during its annual cycle. In this work, we analyzed a coastal site in Patagonia (Argentina) that has been colonized for three decades by U. pinnatifida, focusing on associated microbial communities in three different compartments. An important influence of algae was observed in seawater, especially in the bottom of the algal forest during the austral summer (January) at the moment of greater biomass release. This was evidenced by changes in DOC concentration and its quality indicators (higher Freshness and lower Humification index) and higher DIC. Although maximum values of NH4 and PO4 were observed in January, bottom water samples had lower concentrations than surface water, suggesting nutrient consumption by bacteria during algal DOM release. Concomitantly, bacterial abundance peaked, reaching 4.68 ± 1.33 × 105 cells mL -1 (January), showing also higher capability of degrading alginate, a major component of brown algae cell walls. Microbial community structure was influenced by sampling date, season, sampling zone (surface or bottom), and environmental factors (temperature, salinity, pH, dissolved oxygen, nutrients). Samples of epiphytic biofilms showed a distinct community structure compared to seawater, lower diversity, and remarkably high alginolytic capability, suggesting adaptation to degrade algal biomass. A high microdiversity of populations of the genus Leucothrix (Gammaproteobacteria, Thiotrichales) that accounted for a large fraction of epiphytic communities was observed, and changed over time. Epiphytic assemblages shared more taxa with bottom than with surface seawater assemblages, indicating a certain level of exchange between communities in the forest surroundings. This work provides insight into the impact of U. pinnatifida decay on seawater quality, and the role of microbial communities on adapting to massive biomass inputs through rapid DOM turnover.

3.
Sci Total Environ ; 822: 153320, 2022 May 20.
Artículo en Inglés | MEDLINE | ID: mdl-35074382

RESUMEN

Microplastics (MPs) are considered emerging and persistent pollutants, although most of the research has been conducted on marine environments. Declines in honeybee populations have been reported globally, and recently, microplastic pollution has been considered a possible cause of this. Thus, we aimed to determine acute toxicity of polyester fibers and their effects on foraging behavior in honeybees. To test this, we conducted an oral acute toxicity bioassay, testing the effect of MPs on individual honeybees, and we studied the foraging behavior of honeybees when exposed to food and water containing MPs. We observed no mortality in honeybees fed with sucrose solution containing 100 mg MP/L after 24 and 48 h. Upon bee dissection of the digestive tract, we found 1.27 ± 1.5 fibers per bee, showing a mean (±SE) of 0.92 (±1.14) and 0.32 (±0.70) in their gut and crop respectively. The length of these microfibers ranged between 0.05 and 1.24 mm with a mean (±SE) of 0.42 (±0.25) mm. Although we did not find any preference or avoidance of MPs when presented in sucrose solutions and water; bees consumed MP-free solutions faster than solutions with 10 and 100 mg MPs/L. This might be due to changes in the viscosity of the solutions containing plastic and has implications for the impact of microplastic pollution on insects. Results suggest that MPS do not pose a threat to honeybees in the short term, based on the lack of acute mortality. However, bee foraging behavior does not prevent them from ingesting MPs present in water or resources which potentially might cause lethal long-term effects of MPs.


Asunto(s)
Contaminantes Ambientales , Microplásticos , Animales , Abejas , Conducta Animal , Contaminación Ambiental , Plásticos/toxicidad
4.
Behav Processes ; 189: 104439, 2021 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-34087348

RESUMEN

In the present study we analysed spatial learning in Vespula germanica wasps when dealing with a walking Y-maze. We recorded the time taken to leave the maze during two consecutive visits and which of the two short arms was chosen to exit. Two treatments were conducted to evaluate whether wasps learned to leave the Y-maze guided either by spatial or visual cues. In Treatment 1, the colour of both arms remained unchanged between two consecutive visits; and in Treatment 2, the position of the coloured arm was switched after the first trial. Our results demonstrated that the time taken to exit the maze on the second trial was less than half in both treatments and wasps left the maze from the previously chosen arm, irrespective of its colour. This is the first study to demonstrate spatial learning in V. germanica wasps by using a walking Y-maze. Free flying wasps learned to enter the Y-maze on their own volition, walk through it, collect food and find their way out more rapidly after a single foraging experience. The current experimental device is suitable for the evaluation of spatial memory processes and exploratory behaviour in this species.


Asunto(s)
Avispas , Animales , Bioensayo , Señales (Psicología) , Aprendizaje por Laberinto , Proyectos Piloto , Memoria Espacial
5.
Artículo en Inglés | MEDLINE | ID: mdl-34061660

RESUMEN

Introduction: Cannabis plant uses are widespread across human cultures. The current tendency is to classify Cannabis varieties into chemovars upon their chemical fingerprint, mainly cannabinoids and terpenoids content. The identification of chemovars has important medical implications; however, their pharmacological characterization is costly and time consuming. The goal of this study was to assess whether achene shape variation could be related to Cannabis varieties with contrasting cannabinoid concentrations, as a first approach to chemovar identification. Methods: We used two-dimensional geometric morphometrics (GM) of the achenes and multivariate statistical analysis. We used achenes from five varieties, two from Type II chemotype (expressing both tetrahydrocannabinol [THC] and cannabidiol [CBD]), two Type I (THC-only), and one Type III (CBD-only). Results: The achenes from the different chemotypes were clearly distinguishable. No significant differences between varieties from the same chemotype were observed. The varieties with high THC concentration (Type I) were rounded and bigger, whereas achene from varieties containing only CBD (Type III) had a slender shape with smaller size. Conclusion: Achene shape variation is a potential biomarker of cannabinoid content in the plant flowers. Further studies are needed to confirm the suitability of GM methods for high-throughput screening of Cannabis cultivars, including larger diversity of varieties, and taking into account growth conditions, which can also influence plant chemical fingerprint.

6.
Insect Sci ; 28(1): 231-237, 2021 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-32017382

RESUMEN

The foraging strategy at abundant resources of the social wasp Vespula germanica includes scanning in the direction of the nest while memorizing resource-specific landmarks and contextual cues. In the present study, we sought to explore wasps' behavioral plasticity on foraging trips to resources whose location and composition changed after a single visit. We evaluated how contextual modifications of food displacement and replacements 60 cm apart from the original site, affect re-orientation for re-finding previously memorized food resources. The results showed that wasps detected and collected the resource faster when more changes were introduced on the following visit. If returning foragers discovered several modifications on both the location and the kind of resource, they collected food more rapidly from the displaced dish, than if only a single parameter in the environment had been changed. These findings illustrate the grade of behavioral plasticity in V. germanica while foraging on abundant resources, which may contribute to the understanding of the prodigious invasive success of this species in anthropized environments.


Asunto(s)
Adaptación Fisiológica , Avispas/fisiología , Animales , Conducta Alimentaria , Orientación
7.
Insect Sci ; 28(4): 1103-1108, 2021 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-32594656

RESUMEN

While foraging, Vespula germanica usually return to abundant food sites. During this relocation behavior, these wasps learn to identify contextual cues associated with food position. We analyzed associative blocking in this species, that is, how an association with a conditioned stimulus (CS1) blocks subsequent learning when a novel stimulus (CS2) is added on a second foraging visit. Three groups of wasps (A, B, and C; total 74 individual wasps) were observed while collecting meat during one or two consecutive visits. In group A, an environmental cue (CS1) was paired with food placed at a specific site, and on the second visit, a second cue (CS2) was added while food remained in the same position. In a subsequent testing phase, CS1 was removed and the food source displaced nearby. We then recorded the number of hovers performed over the empty dish (previously baited). Group A wasps appeared to ignore the addition of CS2 on their second visit because they performed fewer hovers over the learned site. For group A, the duration of the decision-making process to finally fly toward the baited dish was shorter than when CS1 and CS2 were presented together on their first visit (group B). This is the first study to demonstrate the occurrence of associative blocking in vespids, confirming that a prior foraging experience influences subsequent food relocation in V. germanica. Our findings reveal that first learning episodes block further associations with novel contextual cues, contributing to understanding of complex cognitive processes involved in V. germanica´s foraging behavior.


Asunto(s)
Conducta Alimentaria , Avispas/fisiología , Animales , Señales (Psicología) , Aprendizaje
8.
Data Brief ; 32: 106171, 2020 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-32904328

RESUMEN

We provide a 16S rRNA gene dataset of prokaryotic assemblages of a subantarctic marine ecosystem. Samples were collected at 2 stations (one near Ushuaia Bay and the other close to Bridges islands in the Beagle Channel). At each station, 2 depths (subsurface and bottom waters) were sampled in february, march, may and september during 2018, giving a total of 10 samples. 16S rRNA gene amplicon sequencing (V4 hypervariable region) was performed with the Illumina MiSeq platform. A total of 1116 amplicon sequence variants (ASVs) were recovered from the dataset. The sequences were taxonomically assigned to Alphaproteobacteria (23 ± 2%, mean ± standard error), Gammaproteobacteria (17 ± 1.5%), Flavobacteriia (8 ± 2%), Deltaproteobacteria (3.7 ± 0.5%), Acidimicrobiia (1.7 ± 0.1%), Planctomycetia (1.9 ± 0.4%), and AB16 group (1.7 ± 0.3%). Sequences affiliated with Archaea were abundant, reaching one third of analyzed sequences, mainly Thaumarchaeota (22 ± 3%), and Thermoplasmata (10 ± 1%). Together, sequences assigned to all these groups accounted for more than 90% of the sequences. This dataset constitutes a valuable resource for future scientific research aiming to unveil the role of these communities in ecosystem services such as carbon and nutrient cycling, and pollutants degradation. This will turn into benefits for future environmental monitoring and preservation actions, considering the tangible heritage of Ushuaia Bay and surrounding waters.

9.
Ansiedad estrés ; 25(2): 66-71, jul.-dic. 2019. graf
Artículo en Español | IBECS | ID: ibc-190725

RESUMEN

INTRODUCCIÓN: Diversas investigaciones dan cuenta de altos niveles de estrés y burnout en profesores, pero pocos estudios analizan intervenciones que busquen aliviar esta problemática. OBJETIVO: Se realizó una intervención centrada en prácticas de atención plena (mindfulness) con el objetivo de promover la autorregulación emocional y disminuir el estrés en profesores de diversos niveles educativos. MATERIAL Y MÉTODOS: Se llevaron a cabo encuentros semanales en los cuales se realizaron diversas prácticas de atención plena y en los que también se abordaron estas temáticas de forma teórica. Se registraron estados iniciales y finales de estrés percibido y afecto positivo y negativo utilizando la Escala de Estrés Percibido y la Escala de Afectividad Positiva y Negativa. Asimismo, cada profesor realizó autorregistros detallando su proceso de cambio. RESULTADOS: Al evaluar los cambios pre-postintervención se encontraron diferencias significativas en ambas escalas. Luego de la intervención, disminuyó el estrés, aumentó el afecto positivo y disminuyó el afecto negativo. Los profesores expresaron haber adquirido mayor conciencia del impacto de su estado psicoemocional sobre la relación con sus alumnos. CONCLUSIONES: Este tipo de intervención basada en la realización de prácticas de atención plena podría favorecer no solo la salud de los profesores, sino también la calidad de los intercambios intersubjetivos


INTRODUCTION: Several studies report high levels of stress and burnout in teachers, but few studies analyze interventions that seek to alleviate this problem. OBJECTIVE: A mindfulness-based intervention was carried out with the objective to promote awareness, emotion self-regulation, and stress reduction in teachers. MATERIAL AND METHODS: Weekly meetings were held addressing these issues in a theoretical and practical way. Initial and final states of perceived stress, and positive and negative affect were assessed, using the Perceived Stress Scale, and the Positive and Negative Affect Schedule. Furthermore, teachers carried out written records of the performed practices, detailing their processes. RESULTS: When evaluating pre-postintervention changes, significant differences were found in both scales. After the intervention, stress decreased and there was an increase in positive emotions and a decrease in negative ones. Likewise, teachers became more aware of the impact that their psycho-emotional state has on the relationship with their students. CONCLUSIONS: This mindfulness based intervention could favor not only teachers' health but also improve intersubjective interactions with their students


Asunto(s)
Humanos , Femenino , Adulto , Persona de Mediana Edad , Docentes/psicología , Estrés Psicológico/prevención & control , Estrés Psicológico/psicología , Emociones , Atención Plena/métodos , Resultado del Tratamiento , Argentina
10.
PLoS One ; 13(11): e0207606, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30496195

RESUMEN

The aim of this work was to characterize the microbial nitrogen cycling potential in sediments from Ushuaia Bay, a subantarctic environment that has suffered a recent explosive demographic growth. Subtidal sediment samples were retrieved in triplicate from two urban points in the Bay, and analyzed through metagenomic shotgun sequencing. Sequences assigned to genes related to nitrification, nitrate reduction and denitrification were predominant in this environment with respect to metagenomes from other environments, including other marine sediments. The nosZ gene, responsible for nitrous oxide transformation into di-nitrogen, presented a high diversity. The majority of NosZ sequences were classified as Clade II (atypical) variants affiliated to different bacterial lineages such as Bacteroidetes, Chloroflexi, Firmicutes, Proteobacteria, Verrucomicrobia, as well as to Archaea. The analysis of a fosmid metagenomic library from the same site showed that the genomic context of atypical variants was variable, and was accompanied by distinct regulatory elements, suggesting the evolution of differential ecophysiological roles. This work increases our understanding of the microbial ecology of nitrogen transformations in cold coastal environments and provides evidence of an enhanced denitrification potential in impacted sediment microbial communities. In addition, it highlights the role of yet overlooked populations in the mitigation of environmentally harmful forms of nitrogen.


Asunto(s)
Archaea/genética , Bacterias/genética , Desnitrificación/genética , Variación Genética , Sedimentos Geológicos/microbiología , Metagenómica , Archaea/aislamiento & purificación , Proteínas Arqueales/clasificación , Proteínas Arqueales/genética , Proteínas Arqueales/metabolismo , Argentina , Bacterias/aislamiento & purificación , Proteínas Bacterianas/clasificación , Proteínas Bacterianas/genética , Proteínas Bacterianas/metabolismo , Bahías , Análisis por Conglomerados , ADN/química , ADN/aislamiento & purificación , ADN/metabolismo , Óxido Nitroso/metabolismo , Filogenia , Análisis de Secuencia de ADN
11.
Microb Ecol ; 75(1): 123-139, 2018 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-28702706

RESUMEN

In this work, we analyzed the community structure and metabolic potential of sediment microbial communities in high-latitude coastal environments subjected to low to moderate levels of chronic pollution. Subtidal sediments from four low-energy inlets located in polar and subpolar regions from both Hemispheres were analyzed using large-scale 16S rRNA gene and metagenomic sequencing. Communities showed high diversity (Shannon's index 6.8 to 10.2), with distinct phylogenetic structures (<40% shared taxa at the Phylum level among regions) but similar metabolic potential in terms of sequences assigned to KOs. Environmental factors (mainly salinity, temperature, and in less extent organic pollution) were drivers of both phylogenetic and functional traits. Bacterial taxa correlating with hydrocarbon pollution included families of anaerobic or facultative anaerobic lifestyle, such as Desulfuromonadaceae, Geobacteraceae, and Rhodocyclaceae. In accordance, biomarker genes for anaerobic hydrocarbon degradation (bamA, ebdA, bcrA, and bssA) were prevalent, only outnumbered by alkB, and their sequences were taxonomically binned to the same bacterial groups. BssA-assigned metagenomic sequences showed an extremely wide diversity distributed all along the phylogeny known for this gene, including bssA sensu stricto, nmsA, assA, and other clusters from poorly or not yet described variants. This work increases our understanding of microbial community patterns in cold coastal sediments, and highlights the relevance of anaerobic hydrocarbon degradation processes in subtidal environments.


Asunto(s)
Bacterias/genética , Bacterias/metabolismo , Sedimentos Geológicos/microbiología , Hidrocarburos/metabolismo , Anaerobiosis , Bacterias/clasificación , Bacterias/aislamiento & purificación , Proteínas Bacterianas/genética , Proteínas Bacterianas/metabolismo , Biodegradación Ambiental , Clima Frío , ADN Bacteriano/genética , Metagenómica , Microbiota , Filogenia , ARN Ribosómico 16S/genética
12.
Mar Drugs ; 15(4)2017 Apr 09.
Artículo en Inglés | MEDLINE | ID: mdl-28397770

RESUMEN

The goal of this work was to identify sequences encoding monooxygenase biocatalysts with novel features by in silico mining an assembled metagenomic dataset of polar and subpolar marine sediments. The targeted enzyme sequences were Baeyer-Villiger and bacterial cytochrome P450 monooxygenases (CYP153). These enzymes have wide-ranging applications, from the synthesis of steroids, antibiotics, mycotoxins and pheromones to the synthesis of monomers for polymerization and anticancer precursors, due to their extraordinary enantio-, regio-, and chemo- selectivity that are valuable features for organic synthesis. Phylogenetic analyses were used to select the most divergent sequences affiliated to these enzyme families among the 264 putative monooxygenases recovered from the ~14 million protein-coding sequences in the assembled metagenome dataset. Three-dimensional structure modeling and docking analysis suggested features useful in biotechnological applications in five metagenomic sequences, such as wide substrate range, novel substrate specificity or regioselectivity. Further analysis revealed structural features associated with psychrophilic enzymes, such as broader substrate accessibility, larger catalytic pockets or low domain interactions, suggesting that they could be applied in biooxidations at room or low temperatures, saving costs inherent to energy consumption. This work allowed the identification of putative enzyme candidates with promising features from metagenomes, providing a suitable starting point for further developments.


Asunto(s)
Metagenoma/genética , Oxigenasas de Función Mixta/genética , Secuencia de Aminoácidos , Bacterias/genética , Biocatálisis , Biotecnología/métodos , Frío , Sistema Enzimático del Citocromo P-450/genética , Cinética , Oxidación-Reducción , Filogenia , Alineación de Secuencia , Especificidad por Sustrato/genética
13.
Insect Sci ; 24(5): 853-858, 2017 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-27273706

RESUMEN

Social insects exhibit complex learning and memory mechanisms while foraging. Vespula germanica (Fab.) (Hymenoptera: Vespidae) is an invasive social wasp that frequently forages on undepleted food sources, making several flights between the resource and the nest. Previous studies have shown that during this relocating behavior, wasps learn to associate food with a certain site, and can recall this association 1 h later. In this work, we evaluated whether this wasp species is capable of retrieving an established association after 24 h. For this purpose, we trained free flying individuals to collect proteinaceous food from an experimental plate (feeder) located in an experimental array. A total of 150 individuals were allowed 2, 4, or 8 visits. After the training phase, the array was removed and set up again 24 h later, but this time a second baited plate was placed opposite to the first. After 24 h we recorded the rate of wasps that returned to the experimental area and those which collected food from the previously learned feeding station or the nonlearned one. During the testing phase, we observed that a low rate of wasps trained with 2 collecting visits returned to the experimental area (22%), whereas the rate of returning wasps trained with 4 or 8 collecting visits was higher (51% and 41%, respectively). Moreover, wasps trained with 8 feeding visits collected food from the previously learned feeding station at a higher rate than those that did from the nonlearned one. In contrast, wasps trained 2 or 4 times chose both feeding stations at a similar rate. Thus, significantly more wasps returned to the previously learned feeding station after 8 repeated foraging flights but not after only 2 or 4 visits. This is the first report that demonstrates the existence of long-term spatial memory in V. germanica wasps.


Asunto(s)
Memoria Espacial , Avispas , Animales
14.
FEMS Microbiol Ecol ; 93(1)2017 01 01.
Artículo en Inglés | MEDLINE | ID: mdl-27815287

RESUMEN

Rhodopsins are broadly distributed. In this work, we analyzed 23 metagenomes corresponding to marine sediment samples from four regions that share cold climate conditions (Norway; Sweden; Argentina and Antarctica). In order to investigate the genes evolution of viral rhodopsins, an initial set of 6224 bacterial rhodopsin sequences according to COG5524 were retrieved from the 23 metagenomes. After selection by the presence of transmembrane domains and alignment, 123 viral (51) and non-viral (72) sequences (>50 amino acids) were finally included in further analysis. Viral rhodopsin genes were homologs of Phaeocystis globosa virus and Organic lake Phycodnavirus. Non-viral microbial rhodopsin genes were ascribed to Bacteroidetes, Planctomycetes, Firmicutes, Actinobacteria, Cyanobacteria, Proteobacteria, Deinococcus-Thermus and Cryptophyta and Fungi. A rescreening using Blastp, using as queries the viral sequences previously described, retrieved 30 sequences (>100 amino acids). Phylogeographic analysis revealed a geographical clustering of the sequences affiliated to the viral group. This clustering was not observed for the microbial non-viral sequences. The phylogenetic reconstruction allowed us to propose the existence of a putative ancestor of viral rhodopsin genes related to Actinobacteria and Chloroflexi. This is the first report about the existence of a phylogeographic association of the viral rhodopsin sequences from marine sediments.


Asunto(s)
Bacterias/genética , Hongos/genética , Sedimentos Geológicos/microbiología , Phycodnaviridae/genética , Agua de Mar/microbiología , Proteínas Virales/genética , Regiones Antárticas , Argentina , Bacterias/clasificación , Evolución Molecular , Hongos/clasificación , Sedimentos Geológicos/virología , Metagenoma , Noruega , Phycodnaviridae/clasificación , Filogenia , Rodopsina/genética , Agua de Mar/virología , Suecia
15.
Environ Microbiol ; 18(12): 4471-4484, 2016 12.
Artículo en Inglés | MEDLINE | ID: mdl-27348213

RESUMEN

Alginates are abundant polysaccharides in brown algae that constitute an important energy source for marine heterotrophic bacteria. Despite the key role of alginate degradation processes in the marine carbon cycle, little information is available on the bacterial populations involved in these processes. The aim of this work was to gain a better understanding of alginate utilization capabilities in cold coastal environments. Sediment metagenomes from four high-latitude regions of both Hemispheres were interrogated for alginate lyase gene homologue sequences and their genomic context. Sediments contained highly abundant and diverse bacterial assemblages with alginolytic potential, including members of Bacteroidetes and Proteobacteria, as well as several poorly characterized taxa. The microbial communities in Arctic and Antarctic sediments exhibited the most similar alginolytic profiles, whereas brackish sediments showed distinct structures with a higher proportion of novel genes. Examination of the gene neighbourhood of the alginate lyase homologues revealed distinct patterns depending on the potential lineage of the scaffolds, with evidence of evolutionary relationships among alginolytic gene clusters from Bacteroidetes and Proteobacteria. This information is relevant for understanding carbon fluxes in cold coastal environments and provides valuable information for the development of biotechnological applications from brown algae biomass.


Asunto(s)
Alginatos/metabolismo , Bacterias/genética , Bacterias/metabolismo , Sedimentos Geológicos/microbiología , Metagenómica , Regiones Antárticas , Regiones Árticas , Ecosistema , Ácido Glucurónico/metabolismo , Ácidos Hexurónicos/metabolismo , Metagenoma , Polisacárido Liasas , Polisacáridos/metabolismo
16.
Front Psychol ; 7: 393, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27047420

RESUMEN

Converging evidence highlights the relevance of embodied cognition in learning processes. In this study we evaluate whether embodied action (enaction) improves cognitive understanding in children. Using the Piagetian conservation tasks in 6-7 year olds, we analyzed quantity conservation conceptualization in children who were active participants in the transformation process and compared these results to those of children who were mere observers of an adult's demonstration (as traditionally conducted). The investigation was performed with 105 first-graders. Conservation tasks were demonstrated to half the children, while the other half actively carried out the transformation of matter. Our findings showed that active manipulation of the material helped children recognize quantity invariance in a higher proportion than when the demonstration was only observed. That is, their enactive experience enabled them to comprehend conservation phenomena more easily than if they were merely passive observers. The outcome of this research thus emphasizes how active participation benefits cognitive processes in learning contexts, promoting autonomy, and agency during childhood.

17.
PLoS One ; 11(3): e0152080, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-26990864

RESUMEN

Vespula germanica is a social wasp that has become established outside its native range in many regions of the world, becoming a major pest in the invaded areas. In the present work we analyze social communication processes used by V. germanica when exploiting un-depleted food sources. For this purpose, we investigated the arrival pattern of wasps at a protein bait and evaluated whether a forager recruited conspecifics in three different situations: foragers were able to return to the nest (full communication), foragers were removed on arrival (communication impeded), or only one forager was allowed to return to the nest (local enhancement restricted). Results demonstrated the existence of recruitment in V. germanica, given that very different patterns of wasp arrivals and a higher frequency of wasp visits to the resource were observed when communication flow between experienced and naive foragers was allowed. Our findings showed that recruitment takes place at a distance from the food source, in addition to local enhancement. When both local enhancement and distant recruitment were occurring simultaneously, the pattern of wasp arrival was exponential. When recruitment occurred only distant from the feeder, the arrival pattern was linear, but the number of wasps arriving was twice as many as when neither communication nor local enhancement was allowed. Moreover, when return to the nest was impeded, wasp arrival at the bait was regular and constant, indicating that naive wasps forage individually and are not spatially aggregated. In conclusion, this is the first study to demonstrate recruitment in V. germanica at a distance from the food source by modelling wasps' arrival to a protein-based resource. In addition, the existence of correlations when communication was allowed and reflected in tandem arrivals indicates that we were not in the presence of random processes.


Asunto(s)
Conducta Animal , Conducta Social , Avispas/fisiología , Animales , Conducta Alimentaria , Aprendizaje
18.
Microb Ecol ; 71(1): 100-12, 2016 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-26547568

RESUMEN

We aimed to gain insight into the alkane degradation potential of microbial communities from chronically polluted sediments of a subantarctic coastal environment using a combination of metagenomic approaches. A total of 6178 sequences annotated as alkane-1-monooxygenases (EC 1.14.15.3) were retrieved from a shotgun metagenomic dataset that included two sites analyzed in triplicate. The majority of the sequences binned with AlkB described in Bacteroidetes (32 ± 13 %) or Proteobacteria (29 ± 7 %), although a large proportion remained unclassified at the phylum level. Operational taxonomic unit (OTU)-based analyses showed small differences in AlkB distribution among samples that could be correlated with alkane concentrations, as well as with site-specific variations in pH and salinity. A number of low-abundance OTUs, mostly affiliated with Actinobacterial sequences, were found to be only present in the most contaminated samples. On the other hand, the molecular screening of a large-insert metagenomic library of intertidal sediments from one of the sampling sites identified two genomic fragments containing novel alkB gene sequences, as well as various contiguous genes related to lipid metabolism. Both genomic fragments were affiliated with the phylum Planctomycetes, and one could be further assigned to the genus Rhodopirellula due to the presence of a partial sequence of the 23S ribosomal RNA (rRNA) gene. This work highlights the diversity of bacterial groups contributing to the alkane degradation potential and reveals patterns of functional diversity in relation with environmental stressors in a chronically polluted, high-latitude coastal environment. In addition, alkane biodegradation genes are described for the first time in members of Planctomycetes.


Asunto(s)
Alcanos/metabolismo , Bacterias/aislamiento & purificación , Bacterias/metabolismo , Sedimentos Geológicos/microbiología , Contaminantes Químicos del Agua/metabolismo , Bacterias/clasificación , Bacterias/genética , Biodegradación Ambiental , Biodiversidad , Sedimentos Geológicos/análisis , Concentración de Iones de Hidrógeno , Datos de Secuencia Molecular , Filogenia , Agua de Mar/análisis , Agua de Mar/microbiología , Contaminantes Químicos del Agua/análisis
19.
Microbes Environ ; 29(3): 269-76, 2014 Sep 17.
Artículo en Inglés | MEDLINE | ID: mdl-24964812

RESUMEN

The aim of this study was to design a molecular biological tool, using information provided by amplicon pyrosequencing of 16S rRNA genes, that could be suitable for environmental assessment and bioremediation in marine ecosystems. We selected 63 bacterial genera that were previously linked to hydrocarbon biodegradation, representing a minimum sample of the bacterial guild associated with this process. We defined an ecological indicator (ecological index of hydrocarbon exposure, EIHE) using the relative abundance values of these genera obtained by pyrotag analysis. This index reflects the proportion of the bacterial community that is potentially capable of biodegrading hydrocarbons. When the bacterial community structures of intertidal sediments from two sites with different pollution histories were analyzed, 16 of the selected genera (25%) were significantly overrepresented with respect to the pristine site, in at least one of the samples from the polluted site. Although the relative abundances of individual genera associated with hydrocarbon biodegradation were generally low in samples from the polluted site, EIHE values were 4 times higher than those in the pristine sample, with at least 5% of the bacterial community in the sediments being represented by the selected genera. EIHE values were also calculated in other oil-exposed marine sediments as well as in seawater using public datasets from experimental systems and field studies. In all cases, the EIHE was significantly higher in oiled than in unpolluted samples, suggesting that this tool could be used as an estimator of the hydrocarbon-degrading potential of microbial communities.


Asunto(s)
Bacterias/metabolismo , Ecosistema , Hidrocarburos/metabolismo , Agua de Mar/química , Contaminantes Químicos del Agua/metabolismo , Bacterias/clasificación , Bacterias/genética , Bacterias/aislamiento & purificación , Biodegradación Ambiental , Biodiversidad , Sedimentos Geológicos/química , Sedimentos Geológicos/microbiología , Hidrocarburos/análisis , Datos de Secuencia Molecular , Filogenia , Agua de Mar/microbiología , Contaminantes Químicos del Agua/análisis
20.
J Physiol Paris ; 108(2-3): 187-93, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-24928417

RESUMEN

In this paper we review several studies on Vespulagermanica behavioral plasticity while relocating a food source in natural environments. This exotic social wasp, which has become established in many parts of the world, displays diverse cognitive abilities when foraging. Given its successful invasiveness worldwide, our initial hypothesis was that this species has great behavioral plasticity, which enables it to face environmental uncertainty. In our work we have analyzed foraging behavior associated with undepleted resources. Throughout several experiments, rapid learning was observed in this species; after few learning experiences they associate diverse contextual cues with a food source. However, by exploring wasp behavior when food suddenly disappeared, either because it had been removed or displaced, we found that they continued searching over a no longer rewarding site for a considerable period of time, suggesting that past experience can hinder new learning. Particularly surprising is the fact that when food was displaced nearby, wasps persisted in searching over the empty dish, ignoring the presence of food close by. We propose that this species could be a suitable model for studying cognitive plasticity in relation to environmental uncertainty.


Asunto(s)
Conducta Alimentaria/fisiología , Aprendizaje/fisiología , Orientación/fisiología , Avispas/fisiología , Animales , Conducta Animal/fisiología , Señales (Psicología) , Conducta Social
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