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1.
Animals (Basel) ; 14(10)2024 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-38791625

RESUMO

Phenotypic traits can evolve independently at different stages of ontogeny, optimizing adaptation to distinct ecological contexts and increasing morphological diversity in species with complex life cycles. Given the relative independence resulting from the profound changes induced by metamorphosis, niche occupation and resource utilization in tadpoles may prompt evolutionary responses that do not necessarily affect the adults. Consequently, diversity patterns observed in the larval shape may not necessarily correspond to those found in the adult shape for the same species, a premise that can be tested through the Adaptive Decoupling Hypothesis (ADH). Herein, we investigate the ADH for larval and adult shape differentiation in Neoaustrarana frogs. Neoaustrarana frogs, particularly within the Cycloramphidae family, exhibit remarkable diversity in tadpole morphology, making them an ideal model for studying adaptive decoupling. By analyzing 83 representative species across four families (Alsodidae, Batrachylidae, Cycloramphidae, and Hylodidae), we generate a morphological dataset for both larval and adult forms. We found a low correlation between larval and adult shapes, species with a highly distinct larval shape having relatively similar shape when adults. Larval morphological disparity is not a good predictor for adult morphological disparity within the group, with distinct patterns observed among families. Differences between families are notable in other aspects as well, such as the role of allometric components influencing shape and morphospace occupancy. The larval shape has higher phylogenetic structure than the adult. Evolutionary convergence emerges as a mechanism of diversification for both larval and adult shapes in the early evolution of neoaustraranans, with shape disparity of tadpoles reaching stable levels since the Oligocene. The widest occupation in morphospace involves families associated with dynamically changing environments over geological time. Our findings support the ADH driving phenotypic diversity in Neoaustrarana, underscoring the importance of considering ontogenetic stages in evolutionary studies.

2.
ISA Trans ; 139: 1-12, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37248112

RESUMO

This paper presents a robust decoupling Model Predictive Controller (MPC) for constrained linear systems with bounded disturbances. The usual explicit decouplers are combined with a suitable augmented state-space representation in order to ensure recursive feasibility, robust constraint satisfaction, and cross-coupling reduction during set-point changes. The proposed approach is flexible with respect to the decoupler choice and the robust MPC algorithm. A robust MPC for tracking piecewise constant references with an artificial target based on nominal prediction is proposed in order to achieve offset-free piecewise constant reference tracking. Two case studies are presented to illustrate the effectiveness of the proposed decoupling strategy.

3.
J Environ Manage ; 334: 117438, 2023 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-36796190

RESUMO

The European Union has identified the Textile and Clothing industry as one of the essential objectives towards carbon neutrality in 2050 in line with the "European Green Deal". There are no previous research papers focused on analysing the drivers and inhibitors of the past greenhouse gas emission changes of the textile and clothing industry in Europe. This paper aims to analyse the determinants of the changes in these emissions, and the disassociation level between emissions and economic growth, throughout the 27 Member States of the European Union, from 2008 to 2018. A Logarithmic Mean Divisia Index that explains the key drivers of the changes in greenhouse gas emissions of European Union Textile and Cloth industry and a Decoupling Index have been applied. The results generally conclude that the intensity and carbonisation effects are key factors that contribute to reducing greenhouse gas emissions. The lower relative weight of the textile and clothing industry throughout the EU-27 was noteworthy, and favours lower emissions, partially counteracted by the activity effect. Also, most Member States have been decoupling the industry's emissions from economic growth. Our policy recommendation shows that if further reductions in greenhouse gas emissions are to be achieved, energy efficiency improvements and cleaner use of energy sources would offset the potential increase in emissions of this industry as a result of a relative increase in its gross value added.


Assuntos
Gases de Efeito Estufa , Gases de Efeito Estufa/análise , Dióxido de Carbono/análise , Indústrias , Desenvolvimento Econômico , Carbono/análise , Vestuário , China
4.
Front Behav Neurosci ; 14: 603245, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33281577

RESUMO

The understanding that hyper-excitability and hyper-synchronism in epilepsy are indissociably bound by a cause-consequence relation has only recently been challenged. Thus, therapeutic strategies for seizure suppression have often aimed at inhibiting excitatory circuits and/or activating inhibitory ones. However, new approaches that aim to desynchronize networks or compromise abnormal coupling between adjacent neural circuitry have been proven effective, even at the cost of enhancing local neuronal activation. Although most of these novel perspectives targeting circuitry desynchronization and network coupling have been implemented by non-pharmacological devices, we argue that there may be endogenous neurochemical systems that act primarily in the desynchronization component of network behavior rather than dampening excitability of individual neurons. This review explores the endocannabinoid system as one such possible pharmacological landmark for mimicking a form of "on-demand" desynchronization analogous to those proposed by deep brain stimulation in the treatment of epilepsy. This essay discusses the evidence supporting the role of the endocannabinoid system in modulating the synchronization and/or coupling of distinct local neural circuitry; which presents obvious implications on the physiological setting of proper sensory-motor integration. Accordingly, the process of ictogenesis involves pathological circuit coupling that could be avoided, or at least have its spread throughout the containment of other areas, if such endogenous mechanisms of control could be activated or potentiated by pharmacological intervention. In addition, we will discuss evidence that supports not only a weaker role played on neuronal excitability but the potential of the endocannabinoid system strengthening its modulatory effect, only when circuitry coupling surpasses a level of activation.

5.
Environ Sci Pollut Res Int ; 27(17): 20685-20698, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32285383

RESUMO

An extensive decomposition analysis was used to research the primary driving forces behind energy-related carbon dioxide emissions per capita for the period 1993 to 2017 in a panel of South American countries. Evidence was found that the effect of per capita renewable productivity was challenging and compromised in South Latin American countries. Decoupling changed from a weak state to a strong decoupling state after the Kyoto protocol. When we remove the renewable productivity per capita effect, the results show that the state of strong decoupling was mainly achieved due to a group of economic drivers, with the negative changes in energy intensity, and in the gross domestic investment, proving to be the most significant contributors to decreasing CO2 emission per capita.


Assuntos
Dióxido de Carbono/análise , Investimentos em Saúde , Desenvolvimento Econômico , América Latina , América do Sul
6.
J Environ Manage ; 262: 110330, 2020 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-32250809

RESUMO

The BRICS countries (Brazil, Russia, India, China and South Africa) are central to future global economic development. However, they are facing both environmental and natural resource stresses due to their rapid economic growth. This study examines the balance between economic benefits and cost of environmental emissions and resource usage in BRICS countries so that future sustainable development insights can be provided. The historical trends of carbon dioxide (CO2), sulfur dioxide (SO2), water, land, energy and material footprints of these countries from 1995 to 2015 are evaluated with a multi-regional input-output model. Also, whether a decoupling relationship exists between economic development, environmental emissions and resources consumption, is examined. In addition, whether environmental emissions and resource usage costs to obtain identical economic gains of these countries in global trade are explored. The major results show that in congruence with economic development, the average annual growth rates of footprint indicators ranged from 0.2% in 1995 to 9.8% in 2015. A decoupling effect did not occur for CO2 emissions or water consumption but did exist for other indicators. Global trade across the supply chain shows to achieve a unit of USD economic benefit from trade, BRICS countries tend to use relatively greater environmental emissions and resource consumption to high income countries, when compared to other income level countries. These emergent economies did receive relatively greater benefits per environmental emissions and resource usage cost from lower-middle and low-income countries.


Assuntos
Dióxido de Carbono , Desenvolvimento Econômico , Brasil , China , Índia , Federação Russa , África do Sul
7.
Biomolecules ; 9(8)2019 08 08.
Artigo em Inglês | MEDLINE | ID: mdl-31398842

RESUMO

Head and neck squamous cell carcinoma (HNSCC) cells that are positive for human papillomavirus (HPV+) favor mitochondrial metabolism rather than glucose metabolism. However, the involvement of mitochondrial metabolism in HNSCC HPV+ cells is still unknown. The aim of this work was to evaluate the role of E6 oncoproteins from HPV16 and HPV18 in the mitochondrial metabolism in an HNSCC model. We found that E6 from both viral types abates the phosphorylation of protein kinase B-serine 473 (pAkt), which is associated with a shift in mitochondrial metabolism. E6 oncoproteins increased the levels of protein subunits of mitochondrial complexes (I to IV), as well as the ATP synthase and the protein levels of the voltage dependent anion channel (VDAC). Although E6 proteins increased the basal and leak respiration, the ATP-linked respiration was not affected, which resulted in mitochondrial decoupling. This increase in leak respiration was associated to the induction of oxidative stress (OS) in cells expressing E6, as it was observed by the fall in the glutathione/glutathione disulfide (GSH/GSSG) rate and the increase in reactive oxygen species (ROS), carbonylated proteins, and DNA damage. Taken together, our results suggest that E6 oncoproteins from HPV16 and HPV18 are inducers of mitochondrial metabolism.


Assuntos
Proteínas de Ligação a DNA/metabolismo , Neoplasias de Cabeça e Pescoço/metabolismo , Mitocôndrias/metabolismo , Proteínas Oncogênicas Virais/metabolismo , Papillomaviridae/química , Proteínas Repressoras/metabolismo , Neoplasias de Cabeça e Pescoço/virologia , Humanos , Mitocôndrias/virologia , Papillomaviridae/metabolismo , Células Tumorais Cultivadas
8.
Rev. biol. trop ; Rev. biol. trop;65(3): 925-938, Jul.-Sep. 2017. tab, ilus
Artigo em Espanhol | LILACS-Express | LILACS | ID: biblio-897593

RESUMO

ResumenEl éxito de anidación ha sido un indicador para evaluar los cambios ambientales que afectan el éxito reproductivo de aves, ya que permite analizar cambios que ocurren en la natalidad. En el presente estudio analizamos el éxito de anidación de Turdus grayi en el Centro Ecológico Recreativo "El Zapotal", Chiapas. Durante la temporada reproductiva del 2015, evaluamos las características del hábitat, presentes en los sitios de anidación a través de la búsqueda intensiva de nidos. Localizamos 56 nidos de los cuales, 27 (48.2 %) fueron exitosos y 29 (51.7 %) fueron fallidos. La mayoría de los nidos no exitosos (19) fueron depredados mientras que 8 (27.6 %) fueron abandonados y 2 (6.9 %) parasitados. El éxito de anidación fue de 46 %. La depredación fue el principal factor del fallo de los nidos. La incubación fue la etapa más susceptible a la depredación.Identificamos que las variables del sitio de anidación operaron a dos escalas espaciales: local y parche del nido. A través del análisis de regresión logística binaria se obtuvo un modelo para cada escala, el cual predijo qué variables incrementaron la probabilidad de éxito de anidación. Además realizamos un análisis de regresión logística multivariante para descartar posibles interacciones entre las variables. A escala local encontramos que la altura del nido a un intervalo de 4.2-5.1 m de altura incrementó el éxito del nido, mientras a escala parche del nido, la probabilidad de éxito de anidación fue mayor en los sitios con una densidad ≥ 12 árboles. Los análisis indicaron que la probabilidad de éxito de anidación no presentó una relación entre la escala local y parche del nido. Lo que sugiere un desacoplamiento de escalas y mecanismos. Por lo cual los cambios que ocurren en las variables que intervienen a escala local parecen no interferir en la escala de parche del nido. Los resultados obtenidos mostraron que la variación en las características de los sitios de anidación podría influir en la depredación además de que la depredación podría haberse presentado de manera aleatoria ya que los nidos que presentaron probabilidades medias y altas de ser exitosos fallaron por esta causa. De este modo, con el fin de comprender los factores, mecanismos y características de historia de vida que influyen en el éxito de anidación, sugerimos que además de las variables ambientales, los estudios futuros deberán considerar el comportamiento de las aves anidantes.


AbstractNesting success has been a surrogate to assess environmental changes that affect the reproductive success of birds, and to analyze changes that influence natality. We analyzed the nesting success of Turdus grayi at "El Zapotal" Recreational Ecological Preserve, Central Chiapas. During the 2015 breeding season, we intensively searched for active nests and evaluated habitat characteristics. We located a total of 56 nests of which 27 (48.2 %) were successful and 29 (51.7 %) were unsuccessful. Most unsuccessful nests (19) were depredated, while 8 (27.6 %) were abandoned and 2 (6.9 %) parasitized. Nesting success was 46 %. Depredation was the main mechanism of nest failure, mostly during incubation. We identified operating variables at site and patch scales. Through analysis of binary logistic regression models for each scale, we predicted which variables increased the probability of nesting success. We also performed a multivariate logistic regression analysis to rule out possible interactions among variables. At nest scale we found that nest height, ranging 4.2 - 5.1 m had increased nesting success, while at patch scale, the probability of nest success was greater at sites with a tree density ≥ 12. Our results indicated that the probability of nesting success did not show a relationship between scales. We suggest a decoupling between scales and mechanism. Thus, habitat changes occurring at local scale did not seem to interfere with the patch scale. Also, our results showed that variation in characteristics at nest scale could also influence depredation, when depredation had been presented at random, since nests with medium and high probability of being successful, failed also for this reason. Thus, in order to understand the factors, mechanisms and life history characteristics influencing nesting success, we suggest that in addition to the environmental variables, future studies should also consider the bird nesting behaviour. Rev. Biol. Trop. 65 (3): 925-938. Epub 2017 September 01.

9.
Neuroimage ; 132: 71-78, 2016 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-26876471

RESUMO

When attention is oriented toward inner thoughts, as spontaneously occurs during mind wandering, the processing of external information is attenuated. However, the potential effects of thought's content regarding sensory attenuation are still unknown. The present study aims to assess if the representational format of thoughts, such as visual imagery or inner speech, might differentially affect the sensory processing of external stimuli. We recorded the brain activity of 20 participants (12 women) while they were exposed to a probe visual stimulus in three different conditions: executing a task on the visual probe (externally oriented attention), and two conditions involving inward-turned attention i.e. generating inner speech and performing visual imagery. Event-related potentials results showed that the P1 amplitude, related with sensory response, was significantly attenuated during both task involving inward attention compared with external task. When both representational formats were compared, the visual imagery condition showed stronger attenuation in sensory processing than inner speech condition. Alpha power in visual areas was measured as an index of cortical inhibition. Larger alpha amplitude was found when participants engaged in an internal thought contrasted with the external task, with visual imagery showing even more alpha power than inner speech condition. Our results show, for the first time to our knowledge, that visual attentional processing to external stimuli during self-generated thoughts is differentially affected by the representational format of the ongoing train of thoughts.


Assuntos
Atenção/fisiologia , Córtex Cerebral/fisiologia , Imaginação/fisiologia , Pensamento/fisiologia , Percepção Visual/fisiologia , Adulto , Ritmo alfa , Eletroencefalografia , Potenciais Evocados , Feminino , Humanos , Masculino , Estimulação Luminosa , Adulto Jovem
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