Metabolic, Ventilatory, and Hygric Physiology of the Gracile Mouse Opossum (Gracilinanus agilis)

We present the first complete study of basic laboratory‐measured physiological variables (metabolism, thermoregulation, evaporative water loss, and ventilation) for a South American marsupial, the gracile mouse opossum (Gracilinanus agilis). Body temperature (Tb) was thermolabile below thermoneutrality (Tb = 33.5°C), but a substantial gradient between Tb and ambient temperature (Ta) was sustained even at Ta = 12°C (Tb = 30.6°C). Basal metabolic rate of 1.00 mL O2 g−1 h−1 at Ta = 30°C conformed to the general allometric relationship for marsupials, as did wet thermal conductance (5.7 mL O2 g−1 h−1 °C−1). Respiratory rate, tidal volume, and minute volume at thermoneutrality matched metabolic demand such that O2 extraction was 12.4%, and ventilation increased in proportion to metabolic rate at low Ta. Ventilatory accommodation of increased metabolic rate at low Ta was by an increase in respiratory rate rather than by tidal volume or O2 extraction. Evaporative water loss at the lower limit of thermoneutrality conformed to that of other marsupials. Relative water economy was negative at thermoneutrality but positive below Ta = 12°C. Interestingly, the Neotropical gracile mouse opossums have a more positive water economy at low Ta than an Australian arid‐zone marsupial, perhaps reflecting seasonal variation in water availability for the mouse opossum. Torpor occurred at low Ta, with spontaneous arousal when Tb > 20°C. Torpor resulted in absolute energy and water savings but lower relative water economy. We found no evidence that gracile mouse opossums differ physiologically from other marsupials, despite their Neotropical distribution, sympatry with placental mammals, and long period of separation from Australian marsupials

Comment on "Effects of cosmic-string framework on the thermodynamical properties of anharmonic oscillator using the ordinary statistics and the q-deformed superstatistics approaches"

We point out a misleading treatment in a recent paper published in this Journal [Eur. Phys. J. C (2018)78:106] regarding solutions for the Schr\"{o}dinger equation with a anharmonic oscillator potential embedded in the background of a cosmic string mapped into biconfluent Heun equation. This fact jeopardizes the thermodynamical properties calculated in this system.Comment: 3 page

Comportamento de mudas enxertadas e crescimento in vitro do Fusarium oxysporum f. sp. passiflorae em diferentes pH do meio.

O maracujá amarelo é plantado em quase todas as regiões brasileiras. O Nordeste produz 76% da produção, com destaque para a Bahia, com 50% da produção do país. Apesar da posição de destaque, a vida útil do maracujazeiro vem sendo reduzida, principalmente, devido aos danos causados por doenças do sistema radicular com destaque para a fusariose (Fusarium oxysporum f. sp. Passiflorae ? Fop)

Se extinções associadas a mudanças climáticas são eventos naturais, por que devemos nos preocupar com o cenário atual?

The climate of Earth is changing in parallel to an accelerated biodiversity lost. Massive extinctions associated with climate change happened already along the history of life in the Earth. So, are we witnessing one more event of natural mass extinction? This assay aims to discuss this question.O clima da Terra está mudando e, simultaneamente, presenciamos uma acelerada perda da biodiversidade. Grandes extinções derivadas de mudanças climáticas já aconteceram na vida na Terra. Estamos, então, presenciando mais um evento natural de extinção em massa? Este ensaio visa discutir essa pergunta