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1.
Artigo em Inglês | MEDLINE | ID: mdl-38692837

RESUMO

Neotropical ecosystems are renowned for numerous examples of adaptive radiation in both plants and animals resulting in high levels of biodiversity and endemism. However, we still lack a comprehensive review of the abiotic and biotic factors that contribute to these adaptive radiations. To fill this gap, we delve into the geological history of the region, including the role of tectonic events such as the Andean uplift, the formation of the Isthmus of Panama, and the emergence of the Guiana and Brazilian Shields. We also explore the role of ecological opportunities created by the emergence of new habitats, as well as the role of key innovations, such as novel feeding strategies or reproductive mechanisms. We discuss different examples of adaptive radiation, including classic ones like Darwin's finches and Anolis lizards, and more recent ones like bromeliads and lupines. Finally, we propose new examples of adaptive radiations mediated by ecological interactions in their geological context. By doing so, we provide insights into the complex interplay of factors that contributed to the remarkable diversity of life in the Neotropics and highlight the importance of this region in understanding the origins of biodiversity.

2.
Evolution ; 77(2): 355-369, 2023 02 04.
Artigo em Inglês | MEDLINE | ID: mdl-36611281

RESUMO

The acoustic adaptation hypothesis (AAH) and ecological character displacement (ECD) are two potential mechanisms shaping call evolution that can predict opposite trends for the differentiation of signals. Under AAH, signals evolve to minimize environmental degradation and maximize detection against background noise, predicting call homogenization in similar habitats due to environmental constraints on signals. In contrast, ECD predicts greater differences in call traits of closely related taxa in sympatry because of selection against acoustic interference. We used comparative phylogenetic analyses to test the strength of these two selective mechanisms on the evolution of advertisement calls in glassfrogs, a highly diverse family of neotropical anurans. We found that, overall, acoustic adaptation to the environment may outweigh effects of species interactions. As expected under the AAH, temporal call parameters are correlated with vegetation density, but spectral call parameters had an unexpected inverse correlation with vegetation density, as well as an unexpected correlation with temperature. We detected call convergence among co-occurring species and also across multiple populations from the same species in different glassfrogs communities. Our results indicate that call convergence is common in glassfrogs, likely due to habitat filtering, while character displacement is relatively rare, suggesting that costs of signal similarity among related species may not drive divergent selection in all systems.


Assuntos
Ecossistema , Vocalização Animal , Animais , Filogenia , Anuros/genética , Acústica , Evolução Biológica
4.
PLoS One ; 15(6): e0234393, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32525904

RESUMO

The concept of rule-governed behavior (RGB) has been used in the behavior-analytic literature as a way to analyze complex human behavior, including thinking and problem-solving. Relational frame theory suggests the existence of two main functional types of RGB termed pliance and tracking. In this paper, we describe the development of the Generalized Tracking Questionnaire (GTQ) and the preliminary evaluation of its psychometric properties and validity through three studies, with a total of 1155 participants. In Study 1, a pool of items describing the main characteristics of generalized tracking was designed and evaluated by experts on the RFT account of RGB. The resulting 11 items were administered to 460 undergraduates to examine the understandability and psychometric quality of the items. The exploratory factor analysis indicated that the GTQ can be seen as a unidimensional scale, with all items exhibiting high factor loadings and corrected item-total correlations. In Study 2, the GTQ was administered online to a sample of 464 non-clinical participants and a clinical sample of 125 participants. The one-factor model of the GTQ obtained a good fit in the conducted confirmatory factor analysis. The GTQ showed measurement invariance across gender and clinical and nonclinical participants. It also obtained excellent internal consistency and correlated in theoretically coherent ways with other constructs. In Study 3, the GTQ and a neuropsychological battery of executive functions were administered to 105 participants. The GTQ showed statistically significant, medium-size correlations with working memory tests, verbal fluency, planning, and behavioral inhibition. In conclusion, the GTQ seems to be a promising measure to advance in the empirical analysis of functional classes of RGB.


Assuntos
Comportamento , Psicometria/métodos , Inquéritos e Questionários , Adolescente , Adulto , Função Executiva , Análise Fatorial , Feminino , Generalização Psicológica , Humanos , Masculino , Resolução de Problemas , Psicometria/normas , Psicometria/estatística & dados numéricos , Adulto Jovem
5.
Zootaxa ; 4732(4): zootaxa.4732.4.9, 2020 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-32230243

RESUMO

Frogs of the genus Eleutherodactylus are direct developing frogs grouped into five subgenera and 192 species, with a geographic distribution primarily centered in the Caribbean (Padial et al. 2014). Eleutherodactylus species inhabit a variety of environments such as tropical and temperate forests, and scrub, where they occupy different microhabitats including caves, floors rich in leaf litter, cracks and cavities of limestone and volcanic outcrops (Reyes-Velasco et al. 2015). Mexico harbors 33 species of Eleutherodactylus (AmphibiaWeb 2018), most of them distributed in central-western and southwestern Mexico (Reyes-Velasco et al. 2015).


Assuntos
Anuros , Florestas , Animais , México
6.
Psychotherapy (Chic) ; 57(3): 444-456, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-31944806

RESUMO

This parallel randomized controlled trial aimed to evaluate the effect of acceptance and commitment therapy (ACT) focused on disrupting repetitive negative thinking (RNT) versus a waitlist control (WLC) in the treatment of depression and generalized anxiety disorder (GAD). Forty-eight participants with a main diagnosis of depression and/or GAD were allocated by means of simple randomization to a 2-session RNT-focused ACT intervention or to the WLC. The primary outcomes were emotional symptoms as measured by the Depression, Anxiety, and Stress Scales-21. Process outcomes included ACT- and RNT-related measures: general RNT, experiential avoidance, cognitive fusion, values, and generalized pliance. At the 1-month follow-up, linear mixed effects models showed that the intervention was efficacious in reducing emotional symptoms (d = 2.42, 95% confidence interval [1.64, 3.19]), with 94.12% of participants in the RNT-focused ACT condition showing clinically significant change in the Depression, Anxiety, and Stress Scales-21 total scores versus 9.09% in the WLC condition (70% vs. 8% in intention-to-treat analysis). The intervention effects were maintained at the 3-month follow-up. No adverse events were found. A very brief RNT-focused ACT intervention was highly effective in the treatment of depression and GAD. (PsycInfo Database Record (c) 2020 APA, all rights reserved).


Assuntos
Terapia de Aceitação e Compromisso/métodos , Transtornos de Ansiedade/terapia , Depressão/terapia , Pessimismo/psicologia , Adulto , Emoções , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Inquéritos e Questionários , Resultado do Tratamento
7.
Ecology ; 100(5): e02685, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30847899

RESUMO

Species traits provide a strong link between an organism's fitness and processes at community and ecosystem levels. However, such data remain scarce for amphibians in the Neotropics. Colombia is the country with the highest number of threatened amphibians and the second greatest number of amphibian species worldwide. We present a data set containing eight morphological traits for 4,623 museum specimens of the seven largest collections in the country corresponding to 293 species of 14 families. The number of measured specimens per species ranged from 1 to 118 individuals with a median of 8 individuals per species. Overall, this database gathered morphological information for 37.6% of Colombian anuran diversity. Species measured were mainly distributed in the high Andean forest, the páramo, and wetland ecosystems, and was part of a national initiative led by the Instituto Alexander von Humboldt. The morphological traits were selected on the basis of their role in species' responses to environmental variability and their contributions to ecosystem processes. These traits were related to habitat use, (forearm length, tibia length, femur length, foot length, and foot webbing), predation and food chains (head width and mouth width), and nutrient recycling (snout-vent length). We expect this data set will be used in studies on functional diversity in amphibians and the development of conservation planning for these taxa. No copyright or proprietary restrictions are associated with the use of this data set other than citation of this Data Paper.

9.
Ter. psicol ; 33(2): 69-80, jul. 2015.
Artigo em Espanhol | LILACS | ID: lil-757199

RESUMO

La depresión es uno de los problemas en salud mental más prevalentes. En Latinoamérica se constituye como la primera problemática en cuanto a años de vida perdidos por incapacidad, lo que implica que se deben hacer esfuerzos importantes en desarrollar estrategias de intervención eficaces para su intervención. Este artículo tiene como objetivo, en primer lugar, ofrecer una revisión conceptual de la activación conductual, una de las estrategias de intervención que han probado ser eficaces en el tratamiento de la depresión y sus diferentes modalidades, en segundo lugar, examinar el uso que ha tenido en el manejo de la depresión en diferentes poblaciones y por último, revisar la evidencia empírica en Iberoamérica.


Depression is nowadays one of the most prevalent mental health problems. In Latin America is the main problem in terms of years of life lost due to disability, implying that major efforts should be made to develop effective intervention strategies for treatment. This article aims, first, to provide a conceptual review of the Behavioral Activation, one of the interventions that have proven to be effective to treat depression and its various forms, secondly, to examine its use to treating depression with different populations and finally, to review the empirical evidence in Latin America.


Assuntos
Humanos , Depressão/psicologia , Depressão/terapia , Terapia Comportamental/métodos , América Latina , Espanha
10.
Mol Imaging ; 12(7): 1-13, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24188593

RESUMO

In heart valve tissue engineering, assessment of cell migration under dynamic states can provide insights on the evolving tissue structure. We labeled human vascular smooth muscle (SMCs), endothelial (ECs), and bone marrow-derived mesenchymal stem cells (BMSCs) with superparamagnetic iron oxide (SPIO) microparticles and visualized them using magnetic resonance imaging (MRI) under steady flow. We determined that vascular cells were able to remain reasonably viable and proliferate well after being labeled with SPIO microparticles (200 µg/mL) for 48 hours. SPIO-labeled cells were successfully visualized using T2* contrast. When physiologically representative shear stresses (5-6 dynes/cm2) were applied to SMC-EC coculture-seeded scaffolds, hypointense regions seemed to have decreased after 2 weeks in some locations, whereas others revealed sustained levels of T2* contrast; similar observations were seen in the case of BMSC-seeded scaffolds. This could be attributable to increased out-of-plane cell migratory activity, which occurred from the fluid-induced mechanical cues received, which was not previously evidenced in static culture. Vascular cells and BMSCs were labeled with remarkably high concentrations of SPIO. Moreover, steady fluid flow enhanced intrascaffold cell migration of vascular SMCs and ECs as well as BMSCs, which, in turn, significantly improved construct cellularity and extracellular collagen content.


Assuntos
Movimento Celular , Rastreamento de Células/métodos , Valvas Cardíacas , Imageamento por Ressonância Magnética/métodos , Engenharia Tecidual , Proliferação de Células , Sobrevivência Celular , Células Cultivadas , Meios de Contraste , Dextranos/metabolismo , Células Endoteliais/citologia , Células Endoteliais/metabolismo , Compostos Férricos , Humanos , Nanopartículas de Magnetita , Células-Tronco Mesenquimais/citologia , Células-Tronco Mesenquimais/metabolismo , Músculo Liso Vascular/citologia , Músculo Liso Vascular/metabolismo
11.
Acta méd. colomb ; 22(1): 8-17, ene.-feb. 1997. tab, graf
Artigo em Espanhol | LILACS | ID: lil-221338

RESUMO

Antecedentes: existe gran interés por hallar las causas subyacentes de la enfermedad cardiovascular. Recientemente factores metabólicos como la respuesta tisular a la insulina han adquirido gran importancia, debido a que la hiperinsulinemia es un factor de riesgo independiente para enfermedad cardiovascular. Se evaluó el efecto de la sensibilidad a la insulina sobre la presión arterial y su relación con otros factores de riesgo cardiovascular. Métodos: se estudiaron 322 adultos sin enfermedad cardiovascular conocida, en la historia clínica se hizo énfasis en la medición del riesgo cardiovascular. Además, se tomaron muestras en ayunas para medir insulina y lípidos séricos; se practicó la prueba de tolerancia oral a la glucosa para determinar el índice de sensibilidad a la insulina (ISI) y el índice de resistencia a la insulina en ayunas (FIRI). Resultados: después de ajustar para el peso corporal, edad y sexo, los niveles séricos de insulina afectaron en forma significativa la presión arterial sistólica (r2=0.45; p<0.001) y diastólica (r2=0.35; p<0.001). Este efecto se acompañó de modificaciones adversas en las lipoproteínas plasmáticas (aumento de los triglicéridos y del colesterol VLDL con disminución en el colesterol-HDL). Así mismo, el peso modifió directamente los niveles de insulinemia en ayuno (r=0.37; p<0.001), independientemente de la edad. Conclusiones: estos resultados muestran que además de variables como el peso, edad y sexo que tienen efecto reconocido sobre la presión arterial, los niveles de insulinemia en ayuno a la sensibilidad a la insulina producen cambios adversos en la presión arterial y las lipoproteínas plasmáticas


Assuntos
Humanos , Insulina/efeitos adversos , Pressão Sanguínea , Fatores de Risco
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