Cognitive flexibility, the ability to appropriately adjust behavior in a changing environment, has been challenging to operationalize and validate in cognitive neuroscience studies. Here, we investigate neural activation and directed functional connectivity underlying cognitive flexibility using an fMRI-adapted version of the Flexible Item Selection Task (FIST) in adults ( = 32, ages 19-46 years). The fMRI-adapted FIST was reliable, showed comparable performance to the computer-based version of the task, and produced robust activation in frontoparietal, anterior cingulate, insular, and subcortical regions.
View Article and Find Full Text PDFThe increased use of CT scans has raised concerns regarding the risks of early radiation exposure in the Puerto Rico pediatric population. Available literature sustains that repeated exposure to imaging-related radiation in the pediatric population is associated with a 3-fold increase in the risk of developing pediatric hematogenous and central nervous system malignancies. It is for this reason that an international effort known as the Image Gently Campaign was created, mostly based on the "As Low As Reasonably Achievable" (ALARA) principle described by the Center for Disease Control.
View Article and Find Full Text PDFThe use of chemical pesticides and herbicides has increased environmental pollution and affected ichthyofauna in the watersheds where they are used. We studied the effect of an herbicide, triazine, on the kidneys of two species (Caquetaia kraussii and Colossomna macropomum) widely found in Caribbean and South American rivers. In Venezuela, these species are abundant and have a high aquaculture potential because they may be cultured and reproduced in captivity.
View Article and Find Full Text PDFThe use of Artemia salina nauplii as live food has significantly aided culture of commercial fish and shrimps in recent years. However, reported deficiencies in the nutritional value of some strains originated the study of freshwater fairy shrimps as an alternative to Artemia. This study presents cyst biometry for Dendrocephalus geayi and D.
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