A paradigm of conversion in Luke.

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Cardiorespiratory physiological phenotypic plasticity in developing air-breathing anabantid fishes (Betta splendens and Trichopodus trichopterus)

Articulo CientificoDevelopmental plasticity of cardiorespiratory physiology in response to chronic hypoxia is poorly understood in larval fishes, especially larval airbreathing fishes, which eventually in their development can at least partially “escape” hypoxia through air breathing. Whether the development air breathing makes these larval fishes less or more developmentally plastic than strictly water breathing larval fishes remains unknown. Consequently, developmental plasticity of cardiorespiratory physiology was determined in two air-breathing anabantid fishes (Betta splendens and Trichopodus trichopterus). Larvae of both species experienced an hypoxic exposure that mimicked their natural environmental conditions, namely chronic nocturnal hypoxia (12 h at 17 kPa or 14 kPa), with a daily return to diurnal normoxia. Chronic hypoxic exposures were made from hatching through 35 days postfertilization, and opercular and heart rates measured as development progressed. Opercular and heart rates in normoxia were not affected by chronic nocturnal hypoxic. However, routine oxygen consumption _ MO2 (~4 lmol O2/g per hour in normoxia in larval Betta) was significantly elevated by chronic nocturnal hypoxia at 17 kPa but not by more severe (14 kPa) nocturnal hypoxia. Routine _ MO2 in Trichopodus (6–7 lmol O2/g per hour), significantly higher than in Betta, was unaffected by either level of chronic hypoxia. PCrit, the PO2 at which _ MO2 decreases as ambient PO2 falls, was measured at 35 dpf, and decreased with increasing chronic hypoxia in Betta, indicating a large, relatively plastic hypoxic tolerance. However, in contrast, PCrit in Trichopodus increased as rearing conditions grew more hypoxic, suggesting that hypoxic acclimation led to lowered hypoxic resistance. Species-specific differences in larval physiological developmental plasticity thus emerge between the relatively closely related Betta and Trichopodus. Hypoxic rearing increased hypoxic tolerance in Betta, which inhabits temporary ponds with nocturnal hypoxia. Trichopodus, inhabiting more permanent oxygenated bodies of water, showed few responses to hypoxia, reflecting a lower degree of developmental phenotypic plasticity.Support for this study was provided by NSF operating grant IOS-1025823 and IOS- 1543301 to Warren Burggren. The Collaboration Network in Comparative Ecophysiology of Vertebrates UAEM-PRODEP 11067 also provided support

Cardiorespiratory physiological phenotypic plasticity in developing air-breathing anabantid fishes (Betta splendens and Trichopodus trichopterus)

Articulo CientificoDevelopmental plasticity of cardiorespiratory physiology in response to chronic hypoxia is poorly understood in larval fishes, especially larval airbreathing fishes, which eventually in their development can at least partially “escape” hypoxia through air breathing. Whether the development air breathing makes these larval fishes less or more developmentally plastic than strictly water breathing larval fishes remains unknown. Consequently, developmental plasticity of cardiorespiratory physiology was determined in two air-breathing anabantid fishes (Betta splendens and Trichopodus trichopterus). Larvae of both species experienced an hypoxic exposure that mimicked their natural environmental conditions, namely chronic nocturnal hypoxia (12 h at 17 kPa or 14 kPa), with a daily return to diurnal normoxia. Chronic hypoxic exposures were made from hatching through 35 days postfertilization, and opercular and heart rates measured as development progressed. Opercular and heart rates in normoxia were not affected by chronic nocturnal hypoxic. However, routine oxygen consumption _ MO2 (~4 lmol O2/g per hour in normoxia in larval Betta) was significantly elevated by chronic nocturnal hypoxia at 17 kPa but not by more severe (14 kPa) nocturnal hypoxia. Routine _ MO2 in Trichopodus (6–7 lmol O2/g per hour), significantly higher than in Betta, was unaffected by either level of chronic hypoxia. PCrit, the PO2 at which _ MO2 decreases as ambient PO2 falls, was measured at 35 dpf, and decreased with increasing chronic hypoxia in Betta, indicating a large, relatively plastic hypoxic tolerance. However, in contrast, PCrit in Trichopodus increased as rearing conditions grew more hypoxic, suggesting that hypoxic acclimation led to lowered hypoxic resistance. Species-specific differences in larval physiological developmental plasticity thus emerge between the relatively closely related Betta and Trichopodus. Hypoxic rearing increased hypoxic tolerance in Betta, which inhabits temporary ponds with nocturnal hypoxia. Trichopodus, inhabiting more permanent oxygenated bodies of water, showed few responses to hypoxia, reflecting a lower degree of developmental phenotypic plasticity.Support for this study was provided by NSF operating grant IOS-1025823 and IOS- 1543301 to Warren Burggren. The Collaboration Network in Comparative Ecophysiology of Vertebrates UAEM-PRODEP 11067 also provided support

Very high blood oxygen affinity and large Bohr shift differentiates the airbreathing siamese fighting fish (Betta splendens) from the closely related anabantoid the blue gourami (Trichopodus trichopterus)

Articulo científicoThe Siamese fighting fish, Betta splendens, and the blue gourami, Trichopodus trichopterus, are two closely related air-breathing anabantoid fishes. B. splendens is a sedentary facultative air breather frequenting often hypoxic waters, whileT. trichopterusisamoreactiveobligatory air-breather inhabiting betteroxygenated waters. Despite their close taxonomic relationship, previous studies have shown inter-specific differences in both physiological and morphological plasticity. Consequently, we hypothesized that B. splendens would have the higher blood oxygen affinity characteristics typical of more hypoxia-tolerant fishes. Whole blood oxygen equilibrium curves were determined at 27°C and pHs of 7.62, 7.44 and 7.25. At a pH of 7.62, the blood O2 affinity (P50) ofB. splendens was just 2.9mmHg, while that of T. trichopterus was ~5 times higher at 14.7mmHg. There were no significant differences in P50 between males and females in either species. The Bohr coefficient in B. splendens and T. trichopterus was −1.79 and−0.83, respectively. B. splendens, unlike T. trichopterus, showed a large Root effect. Hills cooperatively coefficient, n, was ~2 in both species, indicating a significant binding cooperative between oxygen and hemoglobin. Collectively, these differences in blood O2 transport characteristics in these two closely related species are likely correlated with the differing habitats in which they breed and inhabit as adults, as well as different activity levels. Finally, the very high blood O2 affinity of B. splendens is not extraordinary among air-breathing fish, as revealed by a review of the literature of blood oxygen affinity in airbreathing fishes.This work was support by US National Science Foundation Operating Grant1025823. The UAEMgrants “Collaboration Networkin Comparative Ecophysiology of Vertebrates” PRODEP 11067 and “Scientific Research, Innovation, and Development” 4503/2018/CI also provided support

Dark Matter in a bi-metric universe

We study the possibility to describe dark matter in a model of the universe with two scale factors and a non-standard Poisson bracket structure characterized by the deformation parameter \kappa. The dark matter evolution is analyzed in the early stages of the universe, and its relic density is obtained via the Freeze-In and Freeze-Out mechanism. We show that by fixing \k{appa} and the initial ratio of energy densities present in the different sectors of the universe, the space of thermal average annihilation cross-sections and dark matter masses compatible with the standard cosmology prior to Big Bang Nucleosynthesis (BBN), is enlarged. This feature of the model is compatible with non-standard cosmology

Movimientos sociales y crecimiento urbano

En las sociedades actuales la presencia de la sociedad civil organizada se hace cada vez más evidente, y en su actuar, impactan y promueven transformaciones en las relaciones de poder entre las instituciones gubernamentales y actores de la sociedad, constituidos en Organizaciones No Gubernamentales, Comités, patronatos, Asociaciones Civiles, entre otros. Algunos de estos cambios y transformaciones en las relaciones de poder ha sido tan significativas que han llegado a incidir en el diseño de nuevos arreglos institucionales, a través de los cuales la sociedad civil adquiere mayor capacidad de negociación, gestión e incidencia en la toma de decisiones en los distintos niveles de gobierno. Bajo esta premisa para el desarrollo de este trabajo, se tomará como estudio de caso al Comité Pro-Obras de la Unidad Deportiva de Santa Mónica, de la localidad de Santa Mónica, municipio de Ocuilan, y se pretende analizar a través de qué acciones este Comité está incidiendo en la orientación del crecimiento urbano de esta misma localidad

Movimientos sociales y crecimiento urbano

En las sociedades actuales la presencia de la sociedad civil organizada se hace cada vez más evidente, y en su actuar, impactan y promueven transformaciones en las relaciones de poder entre las instituciones gubernamentales y actores de la sociedad, constituidos en organizaciones No Gubernamentales, Comités, patronatos, asociaciones Civiles, entre otros. algunos de estos cambios y transformaciones en las relaciones de poder ha sido tan signifi cativas que han llegado a incidir en el diseño de nuevos arreglos institucionales, a través de los cuales la sociedad civil adquiere mayor capacidad de negociación, gestión e incidencia en la toma de decisiones en los distintos niveles de gobierno. Bajo esta premisa para el desarrollo de este trabajo, se tomará como estudio de caso al Comité Pro-obras de la Unidad Deportiva de Santa mónica, de la localidad de Santa mónica, municipio de ocuilan, y se pretende analizar a través de qué acciones este Comité está incidiendo en la orientación del crecimiento urbano de esta misma localidad