Publications by authors named "J Bernal"
The simultaneous separation of the enantiomers of six anticoagulant rodenticides, derived from 4-hydroxycoumarin, has been studied in this work. Ten different stationary phases (zwitterionic, Pirkle-type, polysaccharides and macrocyclic antibiotics derivatives) were evaluated by using supercritical fluid chromatography coupled to two different detectors (circular dichroism and mass spectrometry-single quadrupole). The effect of the type of organic modifier and temperature on the chiral separation was investigated, and the best results were obtained with the column Regis S,S-Whelk-O1 at 25 °C when using a gradient elution program with methanol as organic modifier.
View Article and Find Full Text PDFThe completion of exercise in different body positions can impact the function of various components of the oxygen delivery pathway; however, the effect of the haemodynamic conditions induced by a semi-upright body position on the integrative physiological response to exercise is poorly understood. The purpose of this study was to explore the effect of a semi-upright body position on cardiac output (CO), vastus lateralis oxygen saturation ( ), oxygen consumption ( ) and ratings of perceived exertion (Borg RPE) during submaximal cycling. Twenty healthy individuals (22 ± 3 years, 50% female) each completed alternating 5-min bouts of submaximal upright and semi-upright (40° incline) cycling at 50 and 100 W.
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- The traditional orbital monsoon hypothesis explains rainfall variations in monsoonal regions primarily through local summer insolation over long time scales, notably seen in Asian and South American records.
- However, some tropical areas show rainfall patterns that don't align with this hypothesis, prompting the exploration of other influencing factors.
- The study presents a 140,000-year Central American rainfall record from stalagmites, suggesting that the Atlantic Ocean's thermal state and the meridional overturning circulation (AMOC) are key drivers of monsoon changes, rather than just local insolation.
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- Jasmonic acid (JA), a plant hormone linked to defense against insect feeding, was found not to influence larval growth, survival, or development speed in western corn rootworm (WCR) when present in low levels in maize.* -
- A study used a double mutant of maize (opr7opr8) that does not produce JA to directly test JA's role in resistance to WCR and found no significant differences in the insects' growth or damage caused to roots.* -
- However, there was a notable reduction in shoot growth related to WCR feeding in the JA-deficient mutant, suggesting JA plays a role in aboveground responses to herbivory rather than root resistance.*
The cognitive reserve (CR) hypothesis posits that individuals can differ in how their brain function is disrupted by pathology associated with aging and neurodegeneration. Here, we test this hypothesis in the continuum from cognitively normal to at-risk stages for Alzheimer's Disease (AD) to AD dementia using longitudinal data from 490 participants of the DELCODE multicentric observational study. Brain function is measured using task fMRI of visual memory encoding.
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