Sistema Regional de Información
en línea para Revistas Científicas de América Latina,
el Caribe, España y Portugal

Introduction. Asian rust caused by the Phakopsorapachyrhizi fungus is the most destructive disease affecting soybeans. The development of transgenic plants that carry defensins offers an alternative to protect the crop. Defensins are small antimicrobial peptides present in plants that play a role in their natural defense mechanism. Methods. Soybean embryogenic axes were transformed with the NmDef02 defensin gene isolated from Nicotianamegalosiphon, using an optimized ballistics transformation methodology that selects shoots resistant to the herbicide glyphosate. The transgenic clones were analyzed molecularly. Nodulation was evaluated in transgenic plants inoculated with the nitrogen-fixing bacterium Bradyrhizobiumjaponicum. The transgenic clones were evaluated in the field against natural infection with P. pachyrhizi, licensed by the National Center for Biological Safety. Results and Discussion. Glyphosate resistant transgenic clones with high transformation efficiency were obtained. Integration and expression of the transgene was confirmed by PCR, Southern blot and qRT-PCR. Efficient nodulation was achieved in roots of transgenic plants inoculated with B. japonicum bacterium. The severity of rust, fungal biomass and defoliation in plants were significantly lower in the transgenic clones. The constitutive expression of the NmDef02 gene in the transgenic clones induced a high resistance to P. pachyrhizi in the field, being higher in plants of the clone Def1. It is concluded that it is the first time that soybean plants have been transformed with a defensin, using a transformation methodology adapted to Cuban genotypes. The expression of the transcript in soybean plants does not affect nodulation by B. japonicum, which is essential for atmospheric nitrogen fixation. It is the first report of resistance to Asian rust in transgenic soybean plants that express the defensin NmDef02.

Introducción: La insuficiencia venosa crónica se define como la inhabilidad de las venas de condescender un retorno adecuado de la sangre al corazón producida por un daño en la estructura de la pared y de las válvulas, lo que conlleva a congestión y daño significativo en la piel, causando limitaciones funcionales significativas y deterioro estético que producen un impacto negativo en la calidad de vida de la población afectadaObjetivo: Comparar la efectividad de las diferentes técnicas en el tratamiento de la enfermedad varicosa con los padecimientos y malestares que pueden suscitar posterior a la aplicaciónMaterial y métodos: El análisis se lo desarrolla mediante los estadísticos de Chi Cuadrado,  Análisis De Correspondencia Múltiple (ACM) y la Regresión Logística Multinomial.Resultados: La Escleroterapia no produce en el paciente la recidiva en el periodo de un año (0,02), tampoco incurre en el aparecimiento de várices en el mismo sitio (0,05) y no la catalogan como una práctica ineficaz (0,01), con esta información se puede enfatizar que la Escleroterapia por sus particularidades es un tratamiento con ínfimos problemas y se corrobora como un tratamiento viable de la categoría de mínimamente invasiva.Conclusiones: Los demás tratamientos mínimamente invasivos disimiles a la Escleroterapia no se los cataloga como ineficaces, tienen resultados prometedores y factibles a largo plazo, sin embargo, es necesario que la investigación de la enfermedad varicosa aumente, con la finalidad de implementar nuevos parámetros a los tratamientos existentes los cuales hagan más exitosa posterior a la aplicación

Introduction. University educational processes are the structural basis of the development of countries, and are linked to the standard of living of its citizens. The Ecuadorean state has experienced a series of changes to university education from the Government of Rafael Correa to the present, actions that deserve careful reflection. The objective of this study is presenting a summary of the main Ecuadorean university educational reforms generated from the Citizen Revolution to the present day. The processes and structural changes generated in university teaching are identified, as well as the primary critical nodes that have affected and currently affect the progressive development of Higher Education Institutions. Methods. A documentary-bibliographical exploration of a total of 70 articles was carried out, selecting the 31 main ones published from 2017 to 2022 from the databases: Scielo, Redalyc, Dialnet, Science.gov and EBSCO. Results. A series of renovations stand out in terms of laws and regulations in Ecuador, which have had an impact on teaching and university education, the main ones being: the reform of the Magna Carta, the Plan for Good Living and the Organic Law of Higher Education. (IT IS). It is concluded there is a progressive and marked development of education since 2009, including the university, inclusion processes were improved, cultural discrimination was eliminated, economic investment for the academy increased, however, it is still necessary to strengthen the processes of admission to university education and setting international standards of excellence as goals.

Introduction. Recommender systems are focused on helping users to find the information that best fits their preferences and needs, in a search space overloaded with possible options. Most of the research works in this area are focused on proposing new recommendation approaches that improve the accuracy of previous work. Methods. Based on this idea, the objective of this research is the development of new data preprocessing methods for removing natural noise in collaborative filtering recommender systems, in order to improve the accuracy of the generated recommendations. Several of the approaches proposed in this research are based on fuzzy logic for managing the uncertainty associated with the user’s preferences as a relevant part of recommender systems. As a result, four new approaches for data preprocessing methods in collaborative recommender systems were obtained, both for individual and group recommendation. Results. The methods proposed were evaluated using international databases created for this purpose, thus verifying their accuracy. Furthermore, these methods were applied in a real recommendation situation associated with Programming Online Judges in Cuba, evidencing an improvement in the recommendation accuracy in such context. These results were published in 8 Group I papers, in Web of Science Journals such as Knowledge-Based Systems and Decision Support Systems. Conclusions-The methods proposed then can be integrated into any collaborative filtering recommendation system, in order to improve its accuracy. Such methods have been clearly applied to situations such as programming online judges.

Introduction. The integrated strategic management developed in Cuba since 2000 as a result of a national project on a platform for integrated management of organizational change evolves towards the Integration of the enterprise management system (ISDE) as a theory in 2007, with the introduction of a new concept “the coordination of all processes through relationships that add value (also called horizontal) or that reinforce the fulfillment of the mission to satisfy the present and future needs of society”. Methods. As a contribution, organizational capabilities of business integration, risk management, and enterprise architecture are developed, with models and methodological procedures for their application, from the development of strategic and process management approaches, and the use of mathematical modeling for the determination of capabilities. Results. The theoretical methodological tools have been applied in the Cuban enterprise system, highlighting the construction, transportation and telecommunications sectors, where there is evidence of an increase in the level of integration of the enterprise management system and an impact on the improvement of economic, productive and service indicators.

Introducción. Babesia caballi, Theileria equi y varias especies de rickettsias son agentes de enfermedades transmitidas por vectores que afectan a los equinos. El objetivo del presente estudio fue detectar infecciones por B. caballi y T. equi en caballos e identificar rickettsias en caballos y garrapatas en la región occidental de Cuba. Métodos. Se estandarizaron 2 ensayos de nPCR para la detección de B. caballi y T. equi. Se colectaron muestras de sangre de caballos, y garrapatas. Se realizó identificación por frotis sanguíneo y detección e identificación molecular de B. caballi, T. equi y Rickettsia sp. Resultados. Se observaron formaciones intraeritrocíticas compatibles con B. caballi y T.  equi. El nPCR mostró que el 25 % de las muestras fueron positivas para B. caballi, 73 % para T. equi y 20 % mostraron coinfección. Los resultados se confirmaron con la secuenciación parcial de los genes bc 48 (B. caballi) y ema-1 (T. equi). La secuenciación del gen ARNr 18S de T. equi demostró la presencia de al menos 2 genotipos de aislados de T. equi en Cuba. El ensayo de PCR en tiempo real y la secuenciación revelaron la presencia de Rickettsia amblyommatis en A. mixtum y Rickettsia felis en D. nitens. Como conclusiones estos resultados constituyen la primera evidencia molecular de B. caballi y T.  equi en equinos y el primer reporte de Rickettsia felis en D. nitens en Cuba, lo que amplía el conocimiento sobre la distribución de patógenos y el espectro de vectores potenciales contribuyendo al fortalecimiento de los programas de manejo y control.

Introduction. The excitation of any sample with a radiofrequency field and the reception of the signal coming from it are of vital importance for its characterization when different techniques of Nuclear Magnetic Resonance (Relaxation, Images and Spectroscopy) are used. The aim of this study is to design an excitation-reception coil for the detection of fluorine-19 Nuclear Magnetic Resonance signals from the polytetrafluoroethylene/graphene oxide composite when nuclear magnetic relaxation is used.Methods. The magnetic induction is calculated inside each coil. Simulations of their respective maps of axial and radial magnetic fields are shown. In addition, the electrical resistance, the magnetic inductance, the sensitivity and the quality factor for each coil are calculated. Results and Discussion.The results show that the first variant of coil induces the greater homogeneity of the radiofrequency magnetic field in the work volume, the lowest values of the magnetic inductance, electrical resistance and magnetic induction of the coil, and the most adequate values of the quality factor and sensitivity. It is concluded that the first variant of excitation-reception coil is the most suitable for the study of the polytetrafluoroethylene/graphene oxide composite characterized by fluorine-19 magnetic relaxation.

Introduction. Today’s Cuban society carries out a process to update its financial economic system. The guidelines of the economic and social policies of the Party and the Revolution, still under implementation, ought to facilitate the use of modern techniques of financial economic management that contribute to increasing, gradually but steadily, both the efficiency and efficacy of the Cuban institutions. The objective of this research is defining the functioning of each component of the national financial economic system, on the basis of determining the financial relations from the perspective of the entrepreneurial system and other forms of economic management present in the Cuban economy. Methods. Several methods were used, that is, reviewing and contrasting bibliographical sources, observation, questionnaires, exchange with specialists, experts’ views, case studies, document analysis, as well as statistical and econometric techniques. Results. The results consider the adequate functioning of each component of the national financial economic system. For that, it was defined how financial relations should be systematized from different perspectives: the entrepreneurial, bank, and insurance systems; the cooperative, self-employment, and mixed sectors; the budgeted units, and the tax administration system. The scientific and practical novelty of the research lies in the fact that financial decisions become essential for the survival and success of the Cuban institutions. As some conclusions was contributions to scientific knowledge are made as regards financial topics that reveal difficulties in the establishment of financial relations among different economic actors. A model of financial management is proposed. It is in tune with the updating of the Cuban economic model.

Introduction. The current research is framed in the introduction of new computational methods of mathematical optimization for multitarget regression problems. Methods. A group of proposals of learning algorithms are included, efficiently modeled by means of optimization methods adjusted to each problem and their applications in the multitarget regression. The introduction of appropriate regularizers is efficiently solved for the simultaneous training of several low range learning structures and distance metric learning. Results and Discussion. It was tested experimentally, on 18 sets of available data. The results show the superiority of the proposal with respect to the state-of-the-art algorithms MSLR and MMR in that the execution times are significantly lower. The meta-heuristic algorithms based on continuation methods proposed in the present work obtain a lower value of the generalization error and training error, with statistically significant difference, with respect to the Stochastic Gradient Descent algorithm in the training of Artificial Neural Networks. The results of introducing the DMLMTP algorithm demonstrate a significant improvement over the KNN-SP algorithm previously proposed as part of the instance-based learning. As some conclusions, modern mathematical optimization methods are proposed for the solution of prediction problems of multiple indicators possibly correlated which improve the accuracy results of the state of the art as their design denotes high efficiency. Concrete applications are achieved in the estimation of the short- and long-term forecasting of COVID-19 that validate the research.

Introduction. The Amparo children’s dispensary was the second institution of this type founded in Cuba. In addition to its welfare functions, it was the headquarters of the Villa Clara Medical Scientific Societies and their most important events. This institution arose at the proposal of the Dental Pharmaceutical Medical Corps, the first Villa Clara scientific society founded in 1892. The objective of this paper is to specify the origin, development and significance of The Amparo dispensary as a scientific institution. Methods. To carry out this research, the historical method was followed, supported by the documentary review technique and interviews with key informants. Documents from the Provincial Historical Archive, the Rare Funds of the José Martí Library, the existing issues of the Villaclara Medical magazine and the provincial press of the time were analyzed. Methodological triangulation was carried out to arrive at integrative considerations. Results. The antecedents of the development of Medical Sciences in Santa Clara were identified, as well as how important institutions and personalities arose at the end of the 19th century and the beginning of the 20th, which allowed for the creation and development of innovative healthcare and scientific institutions for the time. It is concluded that the foundation of the The Amparo dispensary, at the proposal of the Dental Pharmaceutical Medical Corps, represented a step forward for the development of Medical Sciences in the territory and this institution became the scientific headquarters of the societies and subsidiaries that were constituted in Santa Clara and, as a scientific-assistance institution, it lasted until 1962.