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Drepanolejeunea robinsonii (Lejeuneaceae: Drepanolejeuneinae), a new epiphyllous species from the Amazon forest
No full textDrepanolejeunea robinsonii C.E.Zartman & A.M.Sierra is described and illustrated herein as a new species from the Amazon basin. The type collections are from lowland rainforest habitat in the central Amazon of Brazil. Morphological characters which distinguish the new species from the phenotypically similar Drepanolejeunea polyrhiza (Nees) Grolle & R.L.Zhu, are: 1) ovate leaf form; 2) conspicuously acute leaf apices; and 3) irregularly dentate to serrate teeth composed of 2-5 cells on leaf margins. Androecia were repeatedly observed on separate gametophytes suggesting the new taxon is dioecious, however neither gynoecia nor perianths have yet to be observed. © 2019 by The American Bryological and Lichenological Society, Inc
Diversidade genética em três espécies de Mansonia, em áreas próximas a Usina Hidrelétrica Jirau, no Estado de Rondônia
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Hydrological processes interconnecting the two largest watersheds of South America from multi-decadal to inter-annual time scales: A critical review
No full textThe hydrological aspects of the Amazon and the La Plata basins are interconnected through southward moisture transport performed by the Low-Level Jet east of the Andes and the South Atlantic Convergence Zone. Remote effects of sea surface temperature variability in the Pacific and the Atlantic are of varied periodicities, from multi-decadal to inter-annual time scales. Major oscillations thus far detected are Atlantic Multi-decadal Oscillation, Pacific Multi-decadal Oscillation, North Atlantic Oscillation, Atlantic Dipole, Antarctic Oscillation, and the El Niño Southern Oscillation. In the multi-decadal, inter-decadal and decadal time scales, the effects of climate variability over the hydrological processes that interconnect the Amazon and La Plata watersheds are felt predominantly in the South American Monsoon season, while on the inter-annual scale the effects vary along the year. The hydrological memory in Amazonian soils is also responsible for the inter-annual variability of hydrology of the Amazon Basin. Due to the effects of soil water on evapotranspiration, the hydrological memory can affect the supply of moisture to the La Plata Basin, influencing the inter-annual variability of this basin. The implications of the observed oscillations to the hydrological and climatological variability in the two basins are discussed and synthesized in this article. Hypotheses for future research are formulated. © 2019 Royal Meteorological Societ
Growth of parica seedlings (Schizolobium amazonicum Huber ex Ducke) cultivated in different organic substrates
No full textMetabolic fuel use after feeding in the zebrafish (Danio rerio): A respirometric analysis
Get PDFWe used respirometric theory and a new respirometry apparatus to assess, for the first time, the sequential oxidation of the major metabolic fuels during the post-prandial period (10 h) in adult zebrafish fed with commercial pellets (51% protein, 2.12% ration). Compared with a fasted group, fed fish presented peak increases of oxygen consumption (78%), and carbon dioxide (80%) and nitrogen excretion rates (338%) at 7-8 h, and rates remained elevated at 10 h. The respiratory quotient increased slightly (0.89 to 0.97) whereas the nitrogen quotient increased greatly (0.072 to 0.140), representing peak amino acid/protein usage (52%) at this time. After 48-h fasting, endogenous carbohydrate and lipid were the major fuels, but in the first few hours after feeding, carbohydrate oxidation increased greatly, fueling the first part of the post-prandial specific dynamic action, whereas increased protein/amino acid usage predominated from 6 h onwards. Excess dietary protein/amino acids were preferentially metabolized for energy production. © 2019. Published by The Company of Biologists Lt
