Diacol Guadalupe, Diacol Caribe y Diacol Sumapaz, tres nuevas variedades de papa

En trabajos desarrollados en el Centro Nacional de Investigaciones Agropecuarias Tibaitatá y otras estaciones informan de las tres nuevas variedades de papa de buena calidad y alto rendimiento. En la descripción de cada una de estas variedades se anotan sus características más importantes. Diacol-Guadalupe corresponde al híbrido No. 50-44-87 obtenido en 1950, mediante el cruzamiento de la variedad Branca cascuda (S. tuberosum) del brasil y la variedad pajarita careta (S. andigenum) de Colombia. Diacol-Capiro hibrido No. 53-110-13 obtenida en 1953 por cruzamiento entre lineas Escocesas (S. tuberosum) y la variedad tuquerreña (S. andigenum) de Colombia. Diacol Sumapaz, híbrido No. 54-699-2 obtenida en 1954 por cruzamiento de la linea 101 y la variedad algodona (S. andigenum) de Colombia. Todas son de buena producción (de 35 a 50 t/ha), resistentes a la gota y las aspersiones se pueden reducir a la mitadPapa-Solanum tuberosu

THE STRATEGY OF EMPIRICAL RESEARCH AND OPTIMIZATION PROCESS

Empirical modeling is considered from the perspectives of a general scheme for the Strategy of Empirical Research and Optimization Process (SEROP). This approach intends to facilitate the understanding of the necessary steps to arrive to mathematical models able to appropriately describe the behavior of a group of controllable independent variables related to a certain response. Aspects connected with definition of the problem, variable’s identification and optimization stages are discussed. As an example of SEROP application, it is presented the empirical modeling of the basic extraction of alginic acid from brown algae

Effects of gas supersaturation on lethality and avoidance responses in juvenile rock carp (Procypris rabaudi Tchang)*

Laboratory experiments were conducted to determine the effects of total dissolved gas (TDG) supersaturation on acute lethality and avoidance responses in juvenile rock carp (Procypris rabaudi Tchang). The juvenile rock carp were exposed to water with different levels of supersaturation (105%, 115%, 120%, 125%, 130%, 135%, 140%, and 145%) and depth of 0.20 m at 25 °C for 60 h. Median lethal time (LT50) was used to assess the lethal responses corresponding to different levels of gas supersaturation. The results show that half of the juvenile rock carp died at the 120%, 125%, 130%, 135%, 140%, and 145% levels of supersaturation, and the LT50 corresponding to different levels of supersaturation was 18.7, 15.4, 8.2, 6.6, 3.5, and 1.7 h. When the level of supersaturated water is below 115%, the mortality is negligible. Avoidance responses were observed 5 min after the fish were put into equilibrated water (99%, 0.08 m deep) and water with different supersaturated levels (105%, 115%, 125%, 135%, and 145%, 0.08 m deep) at 25 °C. The fish exhibited strong avoidance responses in supersaturated water when the gas supersaturation was above 135%. However, they exhibited an obvious preference to supersaturated water when the gas supersaturation was below 115%. Thus, the juvenile rock carp can likely survive in water with a supersaturated level of 115%

Study protocol for a randomized clinical trial to assess 7 versus 14-days of treatment for Pseudomonas aeruginosa bloodstream infections (SHORTEN-2 trial)

Background Research priorities in Antimicrobial Stewardship (AMS) have rapidly evolved in the last decade. The need for a more efficient use of antimicrobials have fueled plenty of studies to define the optimal duration for antibiotic treatments, and yet, there still are large areas of uncertainty in common clinical scenarios. Pseudomonas aeruginosa has been pointed as a priority for clinical research, but it has been unattended by most randomized trials tackling the effectiveness of short treatments. The study protocol of the SHORTEN-2 trial is presented as a practical example of new ways to approach common obstacles for clinical research in AMS. Objective To determine whether a 7-day course of antibiotics is superior to 14-day schemes for treating bloodstream infections by P. aeruginosa (BSI-PA). Methods A superiority, open-label, randomized controlled trial will be performed across 30 Spanish hospitals. Adult patients with uncomplicated BSI-PA will be randomized to receive a 7 versus 14-day course of any active antibiotic. The primary endpoint will be the probability for the 7-day group of achieving better outcomes than the control group, assessing altogether clinical effectiveness, severe adverse events, and antibiotic exposure through a DOOR/RADAR analysis. Main secondary endpoints include treatment failure, BSI-PA relapses, and mortality. A superiority design was set for the primary endpoint and non-inferiority for treatment failure, resulting in a sample size of 304 patients. Conclusions SHORTEN-2 trial aligns with some of the priorities for clinical research in AMS. The implementation of several methodological innovations allowed overcoming common obstacles, like feasible sample sizes or measuring the clinical impact and unintended effects