Resumen La educación tiene una vasta historia que la ha hecho transitar por diferentes posturas epistemológicas, pragmáticas y ontológicas, situación que ha enriquecido su acervo teórico y práctico. La filosofía es, entre otras, una de las ciencias en las que se ha apoyado la educación parar reflexionar sobre su ser y su hacer. Especialmente, uno de estos sustentos actuales es el pensamiento filosófico sobre el diálogo, que ha ayudado a fortalecer la corriente de la educación dialógica tanto desde su aporte como desde su crítica, aspectos inherentes a la reflexión filosófica. Sin embargo, es evidente que esta corriente de la educación no ha considerado lo suficiente la postura de la mayéutica socrática en su reflexión. Por ello, este artículo tiene como objetivo proponer unos elementos a la educación dialógica desde el estudio de la mayéutica socrática, para lo cual se utiliza una metodología de enfoque cualitativo y de corte hermenéutico. Los principales resultados de la investigación muestran que la educación dialógica amplía su horizonte desde los supuestos socráticos de la mayéutica en dos aspectos particulares: en primer lugar, la mayéutica invita a recuperar la pregunta y la capacidad de preguntarse, y, en segundo lugar, demuestra que el conocimiento para ser significativo debe ser una conquista y un descubrimiento del propio estudiante mediado por el diálogo consigo mismo, con los otros y con lo otro.

Abstract Education has a vast history that has made it go through different epistemological, pragmatic, and ontological positions, which has enriched his theoretical and practical heritage. Philosophy is, among others, one of the sciences in which education has been supported to think on their being and doing. Especially, one of these currents basis is the philosophical thought on dialogue, that has helped to strengthen the trend of dialogical education both from its contribution and from its criticism, aspects inherent to philosophical reflection. However, it is evident that this trend of education has not sufficiently considered the position of Socratic maieutic in its reflection. For this reason, this article aims to propose some elements for dialogical education from the study of Socratic maieutic, for which a qualitative approach and hermeneutic methodology is used. The main results of the research show that dialogical education broadens its horizon from the Socratic assumptions of maieutic in two aspects: in the first place, maieutic invites to recover the question and the ability to ask oneself, and, secondly, it demonstrates that knowledge, to be significant, must be a conquest and discovery of the student himself mediated by dialogue with himself, with others and with the other.

Resumen El objetivo de este trabajo fue diagnosticar de forma participativa la comunidad rural de San Miguel Tlanichico, perteneciente al estado de Oaxaca, México, en 2020, para determinar la viabilidad de implementar una tecnología apropiada, como propuesta de solución al problema de saneamiento de aguas residuales (SAR). La metodología empleada se llevó a cabo en dos fases; en la primera se realizó una revisión bibliográfica del medio natural y construido de la comunidad San Miguel Tlanichico y en la segunda fase se efectuaron recorridos de campo donde se aplicó una encuesta diseñada con 27 ítems agrupados en cuatro ejes temáticos: 1). Percepción de la problemática; 2). Cultura del agua; 3). Saneamiento de las aguas residuales; y 4). Disposición a la capacitación en tecnologías para el tratamiento de aguas residuales. Este instrumento fue aplicado en un censo a 137 personas de la comunidad en sus viviendas. A partir del diagnóstico realizado se identificó que 94.89%, reconoció que existen problemas ambientales en su comunidad, 57.69% percibe la contaminación del agua como problema prioritario, 30.30% señalaron que no realizan el SAR generadas y 73.72% indicaron que si asistirían a algún curso para capacitarse en la construcción de tecnologías apropiadas de saneamiento. Los resultados anteriores reflejan que resulta fundamental conocer la problemática y la disponibilidad de las personas para poder adoptar una tecnología, para ello se requiere de realizar diagnósticos participativos y la etnografía, con la finalidad de identificar la cultura de las personas y las comunidades.

Abstract The objective of this work was to diagnose in a participatory way the rural community of San Miguel Tlanichico, belonging to the state of Oaxaca, Mexico, in 2020, to determine the feasibility of implementing an appropriate technology, as a solution proposal for the problem of wastewater sanitation (WWS). The methodology used was carried out in two phases; in the first, a bibliographic review of the natural and built environment of the San Miguel Tlanichico community was carried out and in the second phase, field tours were carried out where a survey designed with 27 items grouped into the following four thematic axes was applied: 1). Perception of the problems; 2). Water culture; 3). Wastewater sanitation; and 4). Willingness to train in technologies for wastewater treatment. This instrument was applied in a census to 137 people from the community in their homes. From the diagnosis made, it was identified that 94.89% recognized that there are environmental problems in their community, 57.69% perceive water pollution as a priority problem, 30.30% indicated that they do not perform the sanitation of WW generated and 73.72% indicated that they would attend a course to train in the building of appropriate sanitation technologies. The above results reflect that it is essential to know the problems and willingness of people to be able to adopt a technology, for this it is necessary to carry out participatory diagnoses and ethnography in order to identify the culture of people and communities.

Abstract Ellagic acid (EA) is a phenolic biomolecule. For its biosynthesis, a source of ellagitannins is required, such as strawberries and yeasts, as precursors of the tannase and β-glucosidase enzymes responsible for hydrolysis of ellagitannins. Two experimental mixture designs were applied., varying the yeast concentration and the number of ellagitannins in the culture medium, evaluating the enzymatic activity and ellagic acid biosynthesis. Aiming to find the optimal compositions of the non-conventional yeasts assessed in the research to biosynthesize ellagic acid feasibly and efficiently using a response surface performing the statistical analysis in the StatGraphics® program for obtaining a higher yield and optimizing the ellagic acid synthesis process, the results indicate that the strains Candida parapsilosis ITM LB33 and Debaryomyces hansenii ISA 1510 have a positive effect on the synthesis of ellagic acid, since as its concentration increases in the mixture the concentration of ellagic acid in the medium also increases; on the other hand, the addition of Candida utilis ITM LB02 causes a negative effect, resulting in the compositions of 0.516876, 0.483124 and 2.58687E-9 respectively, for a treatment under the same conditions, an optimal value of ellagic acid production would be obtained. With an approximate value of 7.33036 mg/mL.

ABSTRACT Objective: To evaluate the antibacterial effect of electrolytically generated hypochlorous acid on Streptococcus gordonii, Fusobacterium nucleatum, and Porphyromonas gingivalis. Material and Methods: In this in vitro experiment, the effect of hypochlorous acid (HOCl) on the strains S. gordonii, F. nucleatum, and P. gingivalis was evaluated using 4% sodium hypochlorite, 0.12% chlorhexidine, and distilled water as controls. The four groups were placed on each plate, and each group was replicated five times. The agar diffusion method by zones measurement was used. The data were processed with SPSS using the Kruskal-Wallis test and multiple comparison tests. Results: Hypochlorous acid showed an average inhibition halo of 9.28 mm on S. gordonii. As expected with distilled water, no zone of inhibition was noted for any of the bacteria, nor were zones of inhibition observed with HOCl for F. nucleatum and P. gingivalis. Conclusion: Hypochlorous acid showed antimicrobial properties against only S. gordonii and was less effective than 4% sodium hypochlorite and 0.12% chlorhexidine, although no significant differences were found between the latter.

Resumen El emprendimiento agrícola es uno de los factores que influyen en la creación de empleo, el ingreso económico y la competitividad del sector agrícola. Debido a la relevancia del tema es importante explorar la literatura de los últimos años e identificar las habilidades empresariales que los agricultores pueden desarrollar mediante capacitación para el éxito de sus iniciativas empresariales. El objetivo de este trabajo es presentar un análisis bibliométrico para medir la producción científica y revelar temas de capacitación para el emprendimiento agrícola. La búsqueda de información se efectuó en la base de datos de Scopus y Web of Science en el periodo 2010-2020. La delimitación de los grupos temáticos se logró mediante VOSviewer, con base en la técnica bibliométrica de coocurrencia de términos. Se encontró que los artículos publicados incrementaron en los últimos años y se identificaron cuatro grupos temáticos sobre el desarrollo de habilidades empresariales agrícolas. Los hallazgos de esta investigación pueden emplearse para el diseño de cursos de capacitación o pueden orientar al diseño de políticas públicas que fortalezcan el sector agrícola.

Abstract Agricultural entrepreneurship is one of the factors that influence job creation, economic income and competitiveness of the agricultural sector. Due to the relevance of the topic, it is important to explore the literature of recent years and identify the business skills that farmers can develop through training for the success of their business initiatives. The objective of this work is to present a bibliometric analysis to measure scientific production and reveal training topics for agricultural entrepreneurship. The information search was carried out in the Scopus and Web of Science databases in the period 2010-2020. The delimitation of the thematic groups was achieved by VOSviewer, based on the bibliometric technique of co-occurrence of terms. It was found that published papers increased in recent years and four thematic groups on the development of agricultural business skills were identified. The findings of this research can be used for the design of training courses or can guide the design of public policies that strengthen the agricultural sector.

Abstract Introduction Chronic pain is defined as a pain lasting more than 3-6 months. It is estimated that 25% of the pediatric population may experience some kind of pain in this context. Adolescence, corresponding to a particular period of development, seems to present the ideal territory for the appearance of maladaptive mechanisms that can trigger episodes of persistent or recurrent pain. Methods A narrative review, in the PubMed/Medline database, in order to synthetize the available evidence in the approach to chronic pain in adolescents, highlighting its etiology, pathophysiology, diagnosis, and treatment. Results Pain is seen as a result from the interaction of biological, psychological, individual, social, and environmental factors. Headache, abdominal pain, and musculoskeletal pain are frequent causes of chronic pain in adolescents. Pain not only has implications on adolescents, but also on family, society, and how they interact. It has implications on daily activities, physical capacity, school performance, and sleep, and is associated with psychiatric comorbidities, such as anxiety and depression. The therapeutic approach of pain must be multimodal and multidisciplinary, involving adolescents, their families, and environment, using pharmacological and non-pharmacological strategies. Discussion and conclusion The acknowledgment, prevention, diagnosis, and treatment of chronic pain in adolescent patients seem not to be ideal. The development of evidence-based forms of treatment, and the training of health professionals at all levels of care are essential for the diagnosis, treatment, and early referral of these patients.

Abstract The present work completed in January 2021 determined a price hedging model in the coffee futures markets. Following the analytical method, first, the behavior of the historical prices from January 2015 to December 2020 in the spot market and in the futures market was observed and analyzed, later using the standard deviation of the historical data, the volatility that exists in the futures market and its impact on the final price that producers receive for their harvest at the end of each production cycle was calculated. Applying the statistical theory of the binomial tree, the expected prices of the following three four-month periods are estimated, subsequently, the utility function of the producer is modeled, assuming it as the expectation of income and its variance, later the utility function of the producer is found and optimized to know the number of contracts that guarantees the hedging of the price of production. The results of this work suggest that the final income of the producer will depend directly on the production that is expected to have in each productive cycle, on the speculative game on the stock exchange (number of contracts) and on the forecast of the spot price at the time of the evaluation, finally, it is concluded that the producers could be motivated to use futures contracts as a hedging strategy, since even if the profits are not extraordinary, the income will always be higher when such hedging is used.

Resumen El presente trabajo terminado en enero de 2021 determinó un modelo de cobertura de precios en los mercados de futuros de café. Siguiendo el método analítico, primeramente, se observó y analizo el comportamiento de los precios históricos comprendidos de enero de 2015 a diciembre de 2020 en el mercado spot y en el mercado de futuros, posteriormente utilizando la desviación estándar de los datos históricos, se calculó la volatilidad que hay en el mercado de futuros y el impacto de este en el precio final que reciben los productores por su cosecha al finalizar cada ciclo productivo. Aplicando la teoría estadística del árbol binomial se estiman los precios esperados de los siguientes tres cuatrimestres, posteriormente, se modela la función de utilidad del productor asumiéndola como la esperanza del ingreso y la varianza de este, posteriormente se halla y optimiza la función de utilidad del productor para conocer el número de contratos que garantiza la cobertura del precio de la producción. Los resultados de este trabajo sugieren que el ingreso final del productor dependerá directamente de la producción que se espera tener en cada ciclo productivo, del juego especulativo en bolsa (número de contratos) y del pronóstico del precio spot al momento de la evaluación, finalmente se concluye que los productores podrían estar motivados a la utilización de contratos de futuros como una estrategia de cobertura, ya que aunque las ganancias no sean extraordinarias, el ingreso siempre será mayor cuando se utiliza dicha cobertura.

ABSTRACT Some studies have found that severity of COVID-19 is associated with a high viral load determined by the number of cycles (Ct) of SARS-CoV-2 DNA amplification. The objective was to determine the relationship between the Ct value and the severity of the SARS-COV-2 virus infection in inpatients and outpatients at a reference hospital in Paraguay between March and June 2021. Cross-sectional retrospective study of adult patients with COVID-19, ambulatory and hospitalized admitted to the National Hospital. Patients whose infection was confirmed by RT-PCR for SARS-CoV-2 were included, a cut off point of Ct <25 was considered. Five hundred seventeen patients between 16 and 98 years of age were studied (mean ± SD: 51.5 ± 17.5), 268 men (51.8%), age> 60 years (36.6%), hospitalized (69.8%), admitted to ward (57.1%), and admitted to intensive care (12.8%), mean time of illness 8.48 ± 4.2 days and mortality was 22.2%. A higher risk of death was found for patients with Ct <25 for both gene E (OR: 1.61; 95% CI: 1.06-2.44) and gene N2 (OR: 1.83; 95% CI: 1.19- 2.80) and with age> 60 years (OR: 3.69; 95% CI: 2.39-5.68). These two factors remained associated with death in the multivariate analysis. There was a higher risk of hospitalization and death in patients with TC <25. Ct value could be useful for predicting clinical course and prognosis of COVID-19 patients.

RESUMEN Algunos estudios han encontrado que la severidad de la COVID-19 se asocia con una alta carga viral determinada por los números de ciclos (Ct) de amplificación de ADN de SARS-CoV-2. El objetivo fue determinar la relación entre el umbral de ciclos de PCR de SARS-CoV-2 y la severidad de la infección por el virus SARS-COV-2 en pacientes internados y ambulatorios en un hospital de referencia entre marzo a junio del 2021. Estudio retrospectivo observacional analítico de corte trasverso de pacientes adultos con COVID-19, ambulatorios e internados en el Hospital Nacional. Se incluyeron los pacientes cuya infección fue confirmada por RT-PCR para SARS-CoV-2, se consideró un punto de corte para Ct<25. Se estudiaron 517 pacientes entre 16 a 98 años de edad (media ± DE: 51,5±17,5), 268 varones (51,8%), edad >60 años (36,6%), estuvieron hospitalizados (69,8%), internados en sala (57,1%), y admitidos en cuidados intensivos (12,8%), tiempo medio de enfermedad 8,48 ± 4,2 días. La mortalidad fue de 22,2%. Se encontró mayor riesgo de fallecer para los pacientes con Ct <25 tanto para el gen E (OR: 1.61; IC95%: 1,06-2,44) como para el N2 (OR: 1.83; IC95%: 1,19-2,80) y con edad >60 años (OR: 3,69; IC95%: 2,39-5,68). Estos dos factores permanecieron asociados con el óbito en el análisis multivariado. Hubo mayor riesgo de hospitalizarse y fallecer en los pacientes con Ct<25. El valor Ct podría ser útil para la predicción del curso clínico y el pronóstico de los pacientes con COVID-19.

Abstract Objective: To assess the antibacterial activity of Psidium guajava fractions and their effects on adhesion of a multispecies biofilm consisting of Streptococcus gordonii, Fusobacterium nucleatum, and Porphyromonas gingivalis in vitro. Material and Methods: Guava leaves were obtained from the mountains of northern Peru, where they grow wild and free of pesticides. The antimicrobial activity of 25 mg/mL petroleum ether, 25 mg/mL dichloromethane and 25 mg/mL methanol fractions of P. guajava was evaluated by measuring inhibition halos, as well as the effect on the adhesion of multispecies biofilms at 4, 7 and 10 days of growth by measuring the optical density. In addition, antimicrobial susceptibility was compared using the Kruskal-Wallis test and its multiple comparison tests, and differences in mean biofilm adhesion between each fraction were assessed by repeated measures analysis and the Tukey multiple comparison test. Results: The rank-based Kruskal-Wallis test highlighted differences in the effects of the fractions on the zone of inhibition for each oral bacterium, including S. gordonii (p=0.000), F. nucleatum (p=0.000), and P. gingivalis (p=0.000), the Tukey test showed that the group treated with 0.12% chlorhexidine exhibited the least amount of adhesion, followed by the group treated with the 1.56 mg/mL methanol fraction. Conclusion: The methanol fraction of P. guajava had an antibacterial effect on S. gordonii and P. gingivalis, and the 1.56 mg/mL methanol fraction decreased biofilm adhesion.

Abstract Background: Kawasaki disease (KD) is the leading cause of pediatric acquired heart disease in many countries, however, there are few published studies from Latin America (LA). Aim: To describe the epidemiology, clinical aspects, and treatment of KD in children from Panama as part of the REKAMLATINA-2 in LA. Methods: Retrospective descriptive review of hospitalized patients diagnosed with KD, attended at three main pediatric hospitals of Panama from January-1-2009 to December-31-2013. Results: 111 patients were analyzed, 61(54.9 %) were male. All children were hospitalized, and had a mean length of hospitalization of 5.8 (4-7) days. Median age at admission was 28.9 (12-38) months. Prior to KD final diagnosis, 63.9% patients received antibiotics for other presumed diagnoses. 105 (94.6%) patients received IGIV, 10 (9.5%) were resistant. On initial echocardiogram, 11.7% of cardiovascular complications were reported, of which coronary artery lesions (CALs) were detected in 3 (2.9 %) patients. Conclusion: The data suggest that KD in Panama has an incidence of about 2.05 x 100,000 in children under 15 years of age, and with a frequency 2.6 times higher in children under 3 years. A high rate of antibiotic misuse on outpatient prior to diagnostic confirmation was observed, suggesting KD unawareness and late recognition in Panamá.

Resumen Antecedentes: La enfermedad de Kawasaki (EK) representa la principal causa de cardiopatía pediátrica adquirida en muchos países; sin embargo, hay pocos estudios publicados en Latinoamérica. Objetivo: Describir la epidemiología, los aspectos clínicos y el tratamiento de EK en niños en Panamá como parte del estudio de vigilancia de REKAMLATINA-2 en Latinoamérica. Pacientes y Métodos: Estudio retrospectivo, descriptivo, de pacientes internados con diagnóstico de EK, atendidos en tres hospitales pediátricos de Panamá del 1-enero-2009 al 31-diciembre-2013. Resultados: Se analizaron 111 pacientes, 61(54,9%) eran hombres. Todos fueron hospitalizados, siendo la media de hospitalización de 5,8 (4-7) días. La mediana de edad al ingreso fue de 28,9 (12-38) meses. Un 63,9% recibió antimicrobianos recientemente por otros posibles diagnósticos. Recibieron inmunoglobulina intravenosa (IGIV) 105 (94,6%) pacientes; de éstos, 10 (9,5%) fueron resistentes. Un 11,7% tuvo alteraciones cardiovasculares en el ECO inicial, de las cuales las lesiones coronarias se detectaron en 3 (2,9%) pacientes. Conclusiones: Los datos sugieren que EK en Panamá tiene una incidencia cercana a 2,05 x 100,000 bajo 15 años de edad y una frecuencia 2,6 veces mayor bajo 3 años de edad. Se observó un alto porcentaje de uso de antimicrobianos ambulatoriamente antes de la confirmación diagnóstica, lo cual sugiere reconocimiento tardío de EK en Panamá.

Abstract Non-conventional yeasts represent an alternative for microorganisms that are capable to produce the enzyme Tannase (EC 3.1.1.20), which has many applications is the food and pharmaceutical industry as it stands out for its ability to produce ellagic acid out of the enzymatic hydrolysis of ellagitannins. Ellagic acid has been studied in the medical area for its action against various diseases, as is the case of cancer or heart problems. The investigation was conducted to evaluate seven non-conventional yeasts - Debaryomyces hansenii PYC ISA 1510, Debaryomyces hansenii PYC 2968, Candida parapsilosis, Candida utilis, Pichia pastoris, Pichia kluyveri, Issatchenkia terricola - as producers of the enzyme tannase. This was done in mediums of fermentation with tannic acid (1-3%) and YPD without tannic acid, to determine the activity of the enzyme by two spectrophotometric methods, the first being with rhodamine and the second with methyl gallate, to detect the presence of gallic acid as a product of the hydrolysis of tannic acid. The main results showed that the evaluated non-conventional yeasts all presented activity with the Tannase enzyme, obtaining better detection results with the rhodamine technique for the stability of the formed complex, which gives more precision of the obtained data.

Abstract Introduction Coronavirus disease 19 (COVID-19) is potentially the greatest global public health crisis of this century. This disease emerged as an outbreak of pneumonia of unknown cause in Wuhan, the capital city of the Hubei province in China, in December 2019. Otolaryngologists, head and neck surgeons and dentists are at an increased risk of occupational disease. Objective The present review summarizes currently published evidence of Covid-19 epidemiology, clinical characteristics, treatment and prevention. No proven effective treatments for this disease currently exist. Data Synthesis COVID-19 started from a zoonotic transmission event associated with a large seafood market that also traded in live wild animals, and it soon became clear that efficient person-to-person transmission was also occurring. Symptoms are varied, and not all patients develop all of them. Conclusion Social distancing seems to have been successful in several places in the world. However, this recommendation alone is not enough to contain the disease, and it is not a long-term solution. Large-scale testing by health professionals of representative samples of the population may give an estimate of the progression of the disease. Different treatments are under test and bring hope of a cure to the population. However, no current treatments (April 27, 2020) have been proven to be the key to success in the treatment of patients with COVID-19. Planetary health is a useful concept to understand the current drivers of this pandemic and to draw a roadmap for science and healthcare that may guide actions to fight economic depression and ensure a healthy recovery.

Abstract Characterize the content of phytochemical compounds present in samples of extracts of strawberry (Fragaria sp.) and blackberry (Rubus sp.). The extraction of said compounds was carried out with solutions of polar solvents, such as acetone, ethanol and methanol, using an experimental design with three factors: state of maturity, resting time and temperature. The characterization of these fruits is the beginning of the utilization mainly of ellagitannins to produce ellagic acid. Total phytochemical content was determined by spectrophotometric techniques, for phenolic content it was used Folin-Ciocalteu, for flavonoids it was determined with aluminium chloride, the antioxidant activity was evaluated by the methods of DPPH and ABTS+, the bactericidal effect of the extracts was shown for strains of E. coli and S. aureus. The determination of ellagitannins was performed by spectrometry. The influence of the state of maturity on the response variable was evaluated; it was observed that concentration of phytochemicals increases proportionally to maturity stage. The antioxidant activity was evaluated, determining that extracts obtained exhibit 94% - 95% inhibition. The determination of ellagitannins, finding that the highest concentration of ellagitannins was found in a state of green maturity, for strawberries as well as blackberries.

Abstract The central nervous system (CNS) is an extraordinary and complex communication network that receives voluminous amounts of information simultaneously but is vulnerable to disease and injury. This research emphasizes on the importance of gap junctions in neuropathological conditions and neurodegenerative diseases. Namely, we explore the degree of participation of chemical and electrical synapses within an updated panorama of integrative molecular techniques used for their study. The number of electrical and chemical synapses that coexist in the human brain is unknown, yet they are present in almost all types of cells. Frequently, electrical and chemical synapses are found separately, yet sometimes mixed electrical-chemical synapses are found coupled or together. Unfortunately, synaptic dysfunction has adverse effects on organs and vital structures. In this review, we discuss the most common diseases derived from synaptic dysfunction, as well as their occurrence in Mexico. Similarly, we discuss current treatments for diseases involving human connexins. Studies on the CNS are important to understand how this system works and explain current action mechanisms used as treatments of neuropathologies.

Resumen El sistema nervioso central (SNC) es una red de comunicación extraordinaria y compleja que recibe cantidades voluminosas de información simultáneamente, pero es vulnerable a enfermedades y lesiones. Esta investigación enfatiza la importancia de las uniones gap en condiciones neuropatológicas y enfermedades neurodegenerativas. A saber, exploramos el grado de participación de las sinapsis químicas y eléctricas dentro de un panorama actualizado de las técnicas moleculares integrativas utilizadas para su estudio. Se desconoce la cantidad de sinapsis eléctricas y químicas que coexisten en el cerebro humano, pero están presentes en casi todos los tipos de células. Con frecuencia, las sinapsis eléctricas y químicas se encuentran por separado, aunque a veces las sinapsis mixtas quimicoeléctricas se encuentran acopladas. Desafortunadamente, la disfunción sináptica tiene efectos adversos en los órganos y las estructuras vitales. En esta revisión discutimos las enfermedades más comunes derivadas de la disfunción sináptica, así como su ocurrencia en México. Del mismo modo, discutimos los tratamientos actuales para padecimientos neurológicos que involucran conexinas humanas. Los estudios sobre el SNC son importantes para comprender cómo funciona este sistema y explicar los mecanismos de acción actuales utilizados como tratamientos de neuropatologías.

Abstract This research was carried out in northern Tamaulipas in the autumn-winter 2016-2017 cycle, based on information from 40 grain sorghum producers, where prices of the product, inputs and their technical production coefficients were obtained. With this information, private production costs were calculated. The objective of this work was to determine the competitiveness of the cultivation of sorghum grain by humidity-technology regime and producer size in northern Tamaulipas, by using the methodology of the policy analysis matrix in its private part. The results showed that the three technologies had a positive gain, a private profitability ratio, which was between 20.66% to 26.43% and a private cost ratio that stood between 0.4359 and 0.4642, indicating competitiveness, allowing the payment of internal factors, leaving a positive profit margin, provided that the payment for land rent is not considered. Intermediate consumption was between 62.78% and 71.53% of the value of production, which represents the purchase of inputs and services from other sectors of the economy. The added value varied from 28.47% to 37.22%, representing the minimum contribution in the generation of employment in this crop. In general, the results indicate that on average the three technologies used in production in northern Tamaulipas, without considering the income of the land were profitable and competitive, which allows to expect a future expansion of the production of this grain in the region study.

Resumen La presente investigación se realizó en el norte de Tamaulipas en el ciclo otoño-invierno 2016-2017, se basó en información proveniente de 40 productores de sorgo grano, donde se obtuvieron los precios del producto, de los insumos y de sus coeficientes técnicos de producción. Con esta información se calcularon los costos privados de producción. El objetivo de este trabajo fue determinar la competitividad del cultivo del sorgo grano por régimen de humedad-tecnología y tamaño de productor en el norte de Tamaulipas, mediante el uso de la metodología de la matriz de análisis de política en su parte privada. Los resultados mostraron que las tres tecnologías tuvieron una ganancia positiva, una relación de rentabilidad privada, que se ubicó entre 20.66% a 26.43% y una relación de costo privado que se situó entre 0.4359 y 0.4642, lo que indica competitividad, permitiendo el pago de los factores internos, dejando un margen de ganancia positiva, siempre que no se considere el pago por renta de la tierra. El consumo intermedio se ubicó entre 62.78% y 71.53% del valor de la producción, que representa la compra de insumos y servicios provenientes de otros sectores de la economía. El valor agregado, varió de 28.47% a 37.22%, representando la mínima aportación en la generación de empleo en este cultivo. En general, los resultados indican que en promedio las tres tecnologías usadas en la producción en el norte de Tamaulipas, sin considerar la renta de la tierra fueron rentables y competitivas, lo que permite esperar una futura expansión de la producción de este grano en la región de estudio.