Simón Bolívar University

About: Simón Bolívar University is a education organization based out in Caracas, Venezuela. It is known for research contribution in the topics: Population & Crystallization. The organization has 5912 authors who have published 8294 publications receiving 126152 citations.

Impact of a multidimensional infection control strategy on central line-associated bloodstream infection rates in pediatric intensive care units of five developing countries: findings of the International Nosocomial Infection Control Consortium (INICC)

Abstract: Purpose To analyze the impact of the International Nosocomial Infection Control Consortium (INICC) multidimensional infection control strategy including a practice bundle to reduce the rates of central line-associated bloodstream infection (CLAB) in patients hospitalized in pediatric intensive care units (PICUs) of hospitals, which are members of the INICC, from nine cities of five developing countries: Colombia, India, Mexico, Philippines, and Turkey.

Formation of α-Dicarbonyl Compounds in Beer during Storage of Pilsner

Abstract: With the aim of determining the formation of α-dicarbonyl intermediates during beer aging on the shelf, α-dicarbonyls were identified and quantified after derivatization with 1,2-diaminobenze to generate quinoxalines. The sensory effects of α-dicarbonyls were evaluated by the quantification of key Strecker aldehydes and by GC-olfactometry (GCO)analysis of beer headspace using solid phase microextraction. Four α-dicarbonyls, reported here for the first time, were detected in fresh and aged beers, three were derived from the 2,3-enolization pathway of mono- and disaccharides, and the fourth was derived from the epimerization of 3-deoxy-2-hexosulose. Ten α-dicarbonyls were quantified during beer processing and during different periods of beer aging at 28 °C. The aging periods were from 15 to 105 days. During beer aging, 1-deoxydiuloses were produced and degraded, while 1,4-dideoxydiuloses were produced at the highest rates. The GCO analysis indicated that forced beer aging increased the amounts of furaneol, ...

Breaking of Water-in-Crude-Oil Emulsions. 3. Influence of Salinity and Water−Oil Ratio on Demulsifier Action

Abstract: The stability of water-in-diluted-crude-oil emulsions is found to depend upon the water-phase salinity and the water−oil ratio for different asphaltene and demulsifier concentrations. It is reported that the most stable emulsions are formed when one of the phase volumes largely exceeds the other and that the minimum stability is found at the formulation for which the emulsion inversion takes place. For asphaltene concentrations over 500 ppm, this occurs at a volumetric fraction between 0.3 and 0.7 and, in this range, the higher the water-phase content, the lower the required demulsifier concentration. It is also determined that there is an optimum value of the demulsifier concentration that promotes the fastest separation. At a fixed asphaltene concentration, an increase in salinity generally leads to a lower demulsifier requirement. Finally, at higher asphaltene concentrations, simultaneous increases in salinity and demulsifier concentration are required to attain an optimal rate of emulsion breaking.