Publications by authors named "Kassandra Costa"

El Niño events, the warm phase of the El Niño-Southern Oscillation (ENSO) phenomenon, amplify climate variability throughout the world. Uncertain climate model predictions limit our ability to assess whether these climatic events could become more extreme under anthropogenic greenhouse warming. Palaeoclimate records provide estimates of past changes, but it is unclear if they can constrain mechanisms underlying future predictions.

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Ocean dissolved oxygen (DO) can provide insights on how the marine carbon cycle affects global climate change. However, the net global DO change and the controlling mechanisms remain uncertain through the last deglaciation. Here, we present a globally integrated DO reconstruction using thallium isotopes, corroborating lower global DO during the Last Glacial Maximum [19 to 23 thousand years before the present (ka B.

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Using new and published marine fossil radiocarbon (C/C) measurements, a tracer uniquely sensitive to circulation and air-sea gas exchange, we establish several benchmarks for Atlantic, Southern, and Pacific deep-sea circulation and ventilation since the last ice age. We find the most C-depleted water in glacial Pacific bottom depths, rather than the mid-depths as they are today, which is best explained by a slowdown in glacial deep-sea overturning in addition to a "flipped" glacial Pacific overturning configuration. These observations cannot be produced by changes in air-sea gas exchange alone, and they underscore the major role for changes in the overturning circulation for glacial deep-sea carbon storage in the vast Pacific abyss and the concomitant drawdown of atmospheric CO.

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Fetuses are able to process olfactory stimuli present in the womb and continue to show a preference for these odors for months after birth. Despite the accumulated knowledge about their early ability to perceive odors, there is a lack of validated scales for odor response in newborns. The evaluation of reactions of the olfactory system to environmental stimuli in infants has been defined by methodological theoretical approaches of experimental and clinical assessment tools.

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Objective: To compare the physiological variables and the sleep-wake pattern presented by preterm in nesting and hammock positions after diaper change.

Method: This is a crossover randomized controlled trial. It was conducted with 20 preterm infants who, after diaper change, were placed in nests or hammocks.

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Objective: to analyze the cohort profile of at-risk newborns attended by nurses in a multidisciplinary follow-up clinic, with emphasis on the type of feeding and weight gain, after hospital discharge.

Method: retrospective cohort, whose population is composed of at-risk newborns attended in a 4-year period. Data came from medical records and attendance report, later exported to R Program.

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Objective: To compare the effects of the use of hammocks versus nesting in preterm infants, after diaper changing.

Methods: quasi-experimental study, a cross-over trial with 30 preterm newborns in an intermediate care nursery (ICN) in a public hospital in Brasilia-DF, conducted from November 2011 to March 2012. The effects of the two interventions (nesting and hammock) after diaper changing were assessed.

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The Indo-Pacific warm pool houses the largest zone of deep atmospheric convection on Earth and plays a critical role in global climate variations. Despite the region's importance, changes in Indo-Pacific hydroclimate on orbital timescales remain poorly constrained. Here we present high-resolution geochemical records of surface runoff and vegetation from sediment cores from Lake Towuti, on the island of Sulawesi in central Indonesia, that continuously span the past 60,000 y.

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