Estimación de las necessidades hídricas de la papaya utilizando la aproximación de los coeficientes culturales duales

The use of irrigation in the cultivation of papaya is increasing in recent years. Thus, there is the need for improved knowledge of the most appropriate irrigation scheduling practices to be adopted as well as the more adequate estimation of crop water requirements. With this objective, the simulation model SIMDualKc was adopted and calibrated. The model performs the calculation of crop evapotranspiration (ETc) with the methodology of the dual crop coefficient (Kc = Kcb + Ke), i.e., using a basal crop coefficient to estimate crop transpiration and an evaporation coefficient to estimation soil water evaporation. The research was conducted at the Experimental Station of Irrigation and Drainage, located in Alquízar, Havana, Cuba. The experiments were carried out between March and November 1997 with the papaya var. "Maradol red". The calibration consisted in searching the crop factors relative to the different stages of crop development that minimize the differences between the simulated and observed soil moisture content. Various goodness of fit indicators were used to evaluate the model predictions. It can be concluded that the model was properly calibrated and can be used to generate alternative irrigation schedules that improve water use and productivity of papaya in the considered soil and climate condition

Fostering Resilience in Adolescents at Risk: Study protocol for a cluster randomized controlled trial within the resilience school-based intervention

IntroductionResilience is considered of high relevance when developing interventions to cope with stressful situations. Schools are one of the key settings to promote resilience among adolescents. The purpose of this cluster randomized controlled trial is to assess the effectiveness of an intervention in adolescents at risk, aged 12-to-15 years old, to increase resilience and emotional regulation strategies.MethodsThe recruitment period started in January 2022. Schools will be randomly allocated to control and intervention groups by an external researcher using computer-generated random numbers. The minimum sample size was estimated to be 70 participants per group. Primary health care nurses will carry out the intervention during the school period (January to June 2022). Students will follow a specific training consisting of six 55-min sessions, for 6 weeks. Each session will consist of 5 min of mindfulness, followed by 45 min of the corresponding activity: introducing resilience, self-esteem, emotional regulation strategies, social skills, problem-solving, community resources, social and peer support, and 5 min to explain the activity to do at home. Data will be collected at baseline, 6 weeks, and 24 weeks after the intervention. The child youth resilience measure-32 (CYRM-32) scale will be used to assess the effectiveness of the intervention. This study received a grant in June 2021.DiscussionThe intervention is intended to improve mental health through resilience. Different factors related to resilience will be promoted, such as self-esteem, emotional regulation, social and communication skills, problem-solving and peer support, among others. As it has been designed as a cluster-randomized school-based intervention, we will directly ameliorate the participation and engagement of the target population. With the present intervention, we expect to improve coping skills in adolescents by enhancing resilience capacities

Educación Virtual en los postgrados de la Facultad de Humanidades y Ciencias Jurídicas de la UNAN-Managua

Debido al avance tecnológico en el campo de la educación, se hace estrictamente necesario, que los estudiantes de postgrado de la Facultad de Humanidades y Ciencias Jurídicas, tengan un acercamiento adecuado al uso de las tecnologías de entornos virtuales de aprendizaje, las cuales constituyen un aporte muy significativo para el mejoramiento de la calidad educativa.  En la actualidad se enfrentan muchas limitantes en cuanto al uso de estos recursos tecnológicos educativos y se está trabajando en miras del fortalecimiento del área de informática y en la elaboración de planes de capacitaciones para el personal docente y estudiantes, con el fin de ir superando paulatinamente estas debilidades y lograr un mayor desarrollo en la virtualización de la educación en los estudios de postgrado.  En vista de lo anterior, la Facultad considera como prioritario la  implementar de un modelo de capacitación que posteriormente se aplique tanto a docentes como a estudiantes de los postgrados que se imparten actualmente en la Facultad. Previo a la implementación de estas capacitaciones es recomendable que la Facultad adquiera equipamiento informático y recursos humanos que vengan a fortalecer la Unidad TIC y de esta forma poner a disposición de los participantes de posgrado, los medios y las herramientas necesarias para que puedan tener acceso a estas aplicaciones virtuales y se les pueda brindar el soporte técnico necesaria a los usuarios.  Existe seguridad en expresar que el trabajo constante en esta línea, pronto se materializará  en un mayor grado de desarrollo en la creación y uso de entornos virtuales de enseñanza aprendizaje

Evolución del contenido de carbono orgánico del suelo en una cronosecuencia de reemplazo de plantación de cacao (Theobroma cacao L.) a pastizal

6 páginas, 3 tablas y 1 figuraThe aim of this research was to evaluate the impact of the soil use change of the Cocoa Agroforestry System (CAS) on soil organic carbon (SOC) levels and other indicating soil chemical fertility properties (edaphic density ρb, cation exchange capacity CEC, soil total nitrogen STN), when a soil use change occurs from CAS to grassland (GL). For this, in order to be selected was recorded, considering different time intervals (1-5, 6-10 y 11-20 years). However, a CAS of 20-35 years was considered as a reference. In addition, soil samples were taken at -30 cm depth to determine the contents of SOC, STN, CEC, ρb, soil organic matter (SOM) and the soil C/N ratio. Consequently, the soil penetration resistance was evaluated in situ. The results indicated the change in soil use from CAS to GL, did not cause a significant decrease in the amount of stored SOC (0-30 cm) during the considered time with respect to CAS. However, if only the first -10 cm of soil is sampled, a significant soil compaction is observed throughout a decrease in the CEC value in the long term (20 years).Peer reviewe

Binap-gold (I) versus Binap-silver trifluoroacetate complexes as catalysts in 1,3-dipolar cycloadditions of axomethine ylides

The 1,3-dipolar cycloaddition between azomethine ylides and alkenes is efficiently catalysed by [{(Sa)-Binap-Au(tfa)}2] (Binap=2,2′-bis(diphenylphosphino)-1,1′-binaphthyl; tfa=trifluoroacetyl). Maleimides, 1,2-bis(phenylsulfonyl)ethylene, chalcone and nitrostyrene were suitable dipolarophiles even when using sterically hindered 1,3-dipole precursors. The results obtained in these transformations improve the analogous ones obtained in the same reactions catalysed by [Binap–Ag(tfa)]. In addition, computational studies have also been carried out to demonstrate both the high enantioselectivity exhibited by the chiral gold(I) complex, and the non-linear effect observed in this transformation.This work has been supported by the DGES of the Spanish Ministerio de Ciencia e Innovación (MICINN) (Consolider Ingenio 2010 CSD2007-00006, FEDER-CTQ2007-62771/BQU, CTQ2007/67528, CTQ2010-20387 and by the Hispano-Brazilian project PHB2008-0037-PC), Generalitat Valenciana (PROMETEO/2009/039), the Basque government (grant IT-324-07) and by the University of Alicante

Enantioselective synthesis of proline derivatives by 1,3-dipolar cycloadditions

Research devoted to the synthesis of highly substituted prolines, which are hepatitis C virus inhibitors, using 1,3-dipolar cycloadditions (1,3-DC) of azomethine ylides is described. In the first part, a diastereoselective approach using an inexpensive lactate-derived acrylate as dipolarophile is described. In the second part, our efforts using simple and easily accessible chiral silver(I) and gold(I) complexes as catalysts for enantioselective synthesis of proline derivatives are reviewed. In this case, chiral phosphoramidites and binap have been used as privileged ligands. Parallel to these experimental results, considerable effort was dedicated to run semiempirical density functional theory (DFT) calculations to explain and justify the stereoselectivity of each process.This work has been supported by the DGES of the Spanish Ministerio de Ciencia e Innovación (MICINN) (Consolider INGENIO 2010 CSD2007-00006, FEDER-CTQ2007-62771/BQU, and by the Hispano-Brazilian project PHB2008-0037-PC), Generalitat Valenciana (PROMETEO/2009/039), and by the University of Alicante (GITE-09020-UA)