Implementation of a Nickel-Electroless Coating in Heat Exchanger Pipes Considering the Problem of the Environmental Conditions ofthe Cooling Water Without Recirculation to Increase the Effectiveness Under Uncertainty

VICTOR MANUEL ZEZATTI FLORES GUSTAVO URQUIZA BELTRAN MIGUEL ANGEL BASURTO PENSADO LAURA LILIA CASTRO GOMEZ JUAN CARLOS GARCIA CASTREJON (2022, [Artículo])

This research is based on the operation tube heat exchangers, their use and problematic on hydroelectric power plants. It is based on the design heat exchanger tubes for industrial use, which took the parameters of operation, design, working fluids (air and water) and conditions to assemble a monitoring equipment at appropriate scale for the laboratory, with the necessary measurement instruments to analyze the behavior of heat energy transfer by means of thermocouples, the velocity of the air with a hot wire anemometer and the flow of water with a turbine flow meter, in pipes of different materials: copper, steel 1018 and stainless steel 316L, all in ideal conditions, and with this to found a comparative parameter with pipes of the same materials but under conditions of deterioration with the presence of forced oxidation and with the data mining and support vector machine can be minimized the corrosion problems in pipes.

INGENIERÍA Y TECNOLOGÍA CIENCIAS TECNOLÓGICAS Data mining, Support Vector Machine, Pattern Recognition and Decision Support System, Heat exchangers

Freshwater exchanges and surface salinity in the Colombian basin, Caribbean Sea

Emilio Beier (2017, [Artículo])

Despite the heavy regional rainfall and considerable discharge of many rivers into the Colombian Basin, there have been few detailed studies about the dilution of Caribbean Surface Water and the variability of salinity in the southwestern Caribbean. An analysis of the precipitation, evaporation and runoff in relation to the climate variability demonstrates that although the salt balance in the Colombian Basin overall is in equilibrium, the area south of 12N is an important dilution sub-basin. In the southwest of the basin, in the region of the Panama-Colombia Gyre, Caribbean Sea Water is diluted by precipitation and runoff year round, while in the northeast, off La Guajira, its salinity increases from December to May by upwelling. At the interannual scale, continental runoff is related to El Niño Southern Oscillation, and precipitation and evaporation south of 12°N are related to the Caribbean Low Level Jet. During El Niño years the maximum salinification occurs in the dry season (December-February) while in La Niña years the maximum dilution (or freshening), reaching La Guajira Coastal Zone, occurs in the wet season (September-November). © 2017 Beier et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.

sea water, fresh water, Article, Caribbean, dilution, dry season, El Nino, environmental parameters, evaporation, freshwater exchange, geographic distribution, molecular weight, oscillation, precipitation, river basin, salinity, seasonal variation, s CIENCIAS FÍSICO MATEMÁTICAS Y CIENCIAS DE LA TIERRA CIENCIAS DE LA TIERRA Y DEL ESPACIO OCEANOGRAFÍA OCEANOGRAFÍA

Functional characterization and cellular dynamics of the CDC-42 - RAC - CDC-24 module in neurospora crassa

CYNTHIA LIZZETH ARAUJO PALOMARES (2011, [Artículo])

Rho-type GTPases are key regulators that control eukaryotic cell polarity, but their role in fungal morphogenesis is only beginning to emerge. In this study, we investigate the role of the CDC-42 - RAC - CDC-24 module in Neurospora crassa. rac and cdc-42 deletion mutants are viable, but generate highly compact colonies with severe morphological defects. Double mutants carrying conditional and loss of function alleles of rac and cdc-42 are lethal, indicating that both GTPases share at least one common essential function. The defects of the GTPase mutants are phenocopied by deletion and conditional alleles of the guanine exchange factor (GEF) cdc-24, and in vitro GDP-GTP exchange assays identify CDC-24 as specific GEF for both CDC-42 and RAC. In vivo confocal microscopy shows that this module is organized as membrane-associated cap that covers the hyphal apex. However, the specific localization patterns of the three proteins are distinct, indicating different functions of RAC and CDC-42 within the hyphal tip. CDC-42 localized as confined apical membrane-associated crescent, while RAC labeled a membrane-associated ring excluding the region labeled by CDC42. The GEF CDC-24 occupied a strategic position, localizing as broad apical membrane-associated crescent and in the apical cytosol excluding the Spitzenkörper. RAC and CDC-42 also display distinct localization patterns during branch initiation and germ tube formation, with CDC-42 accumulating at the plasma membrane before RAC. Together with the distinct cellular defects of rac and cdc-42 mutants, these localizations suggest that CDC-42 is more important for polarity establishment, while the primary function of RAC may be maintaining polarity. In summary, this study identifies CDC-24 as essential regulator for RAC and CDC-42 that have common and distinct functions during polarity establishment and maintenance of cell polarity in N. crassa. © 2011 Araujo-Palomares et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.

CDC24 protein, guanine nucleotide exchange factor, protein Cdc42, Rac protein, unclassified drug, cell cycle protein, fungal protein, membrane protein, multiprotein complex, protein Cdc42, Rac protein, allele, apical membrane, article, assay, cell me BIOLOGÍA Y QUÍMICA CIENCIAS DE LA VIDA MICROBIOLOGÍA MICROBIOLOGÍA