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

Remote sensing with large-scale satellite images for precision studies in grasslands has spatial and spectral resolution limitations. Against this, using spectral signs and vegetation indices obtained with microsensors transported by unmanned aerial vehicles (UAV) constitutes a more accurate alternative for biomass estimation. In the fieldwork, images were acquired with microsensors, and fixed transects of 100 m were used where vegetation samples were collected. The photographs acquired with the UAV were processed in Pix 4D, Arc Gis, and algorithms elaborated in R programming language. The biomass estimation was carried out with Multiple Linear Regression, Vector Support Machine, and Random (Forest Random) models. The Random model showed a Kappa coefficient of 0.94 in the training set and 0.901 in the test set (R2 = 0.482). The Random Forest model predicted 3 g/pixel of MV for Puna grass in the rainy season and 2 g/pixel for the dry season; the predicted biomass for the Tola bush was 15 g/pixel of MV for both seasons of the year. The estimation of biomass/hectare for the tolar plant community with its tola shrub and Puna grass components was 6,535.88 kg/ha for the rainy season and 6,588.81 kg/ha for the dry season. The difference between the biomass estimated in the field and the biomass estimated with Random Forest was 5.48% for the rainy season and 9.63% for the dry season.

The corn leaf aphid is considered an important pest associated with maize. This study aimed to discover the trophic associations around Rhopalosiphum maidis in Manabí, Ecuador. Maize leaves were sampled to determine the numbers of parasitized aphids, and the identities of predators and parasitoids. Nine taxa of natural enemies were detected: the primary parasitoid was Lysiphlebus testaceipes Cresson, 1880 (Hymenoptera: Braconidae); the hyperparasitoid Syrphophagus aphidivorus (Mayr, 1876) (Hymenoptera: Encyrtidae); the predatory hoverfly Ocyptamus dimidiatus (Fabricius, 1781) (Diptera: Syrphidae), four species of coccinellids, Cheilomenes sexmaculata (Fabricius, 1781), Cycloneda sanguinea (Linnaeus, 1763), Hippodamia convergens Guerin-Meneville, 1842 and Paraneda pallidula guticollis (Coleoptera: Coccinellidae) and an assassin bug, Zelus sp. (Hemiptera: Reduviidae). A parasitoid, Pachyneuron formosum Walker, 1833 (Hymenoptera: Pteromalidae) emerged from hoverfly pupae. This study reports the presence of the parasitoids S. aphidivorus and P. formosum in Ecuador for the first time. These results increase the knowledge of a four-trophic level relationship (host plant – pest – parasitoids, predators – hyperparasitoids) in a maize agroecosystem as a fundamental basis for biological control programs.

Introduction: chronic urticaria is a heterogeneous demarcated skin disease characterized by the development of wheals or hives. Objective: determination of the clinical characteristics and the pharmacological treatment indicated in patients diagnosed with chronic urticaria. Method: a quantitative, prospective, observational and descriptive study was conducted in a total of 48 patients (the universe) diagnosed with chronic urticaria, Main Military Hospital, Guinea-Bissau, 2018-2020. The following variables were used: age, sex, type of urticaria, time of evolution, comorbidity and treatment used in the first and last recorded consultation, as well as disease activity. Results: the mean age was 38.52 years with a female predominance. The mean time of evolution of the disease was 4.67 years and 70.83 % did not present angioedema. Chronic spontaneous urticaria was the predominant type. cyproheptadine was the treatment most indicated to be used at baseline and at the end of treatment follow-up its use increased. montelukast was the other drug that increased its use at the end of follow-up. With the treatment used disease activity was reduced up to rates recognized as controlled chronic spontaneous urticaria.Conclusions: chronic urticaria in Guinea-Bissau has prevalence and clinical manifestations in line with those reported worldwide, with treatment regimens susceptible to modifications depending on the early use of recommended drugs such as cyclosporine or omalizumab.

Introduction: despite the devastating effect of COVID-19, many nations have lifted their restrictions. It is necessary to keep addressing this problem using the promotion via, in order to increase people's health training. Objective: to assess the efficacy of an educational program performed to increase the level of knowledge concerning COVID-19 in patients who live in the Aponwao Village, Caroni, Venezuela, during the period November 2021-February 2022.Method: a pre-experimental intervention study was carried out, with a before-and-after design implied. A total of 85 patients were chosen as sample, selected by simple random sampling. It was applied a survey to all the patients selected, an educational-didactic and interactive program was designed and implemented, and a final evaluation was carried out to verify the effectiveness of the program. Results: female sex was the most representative group (54.1%) and 41.2% of patients were in the age group of 25 to 44. The predominant risk factor was the non-use of means for prevention against Covid 19 infection (28.6 %) and 17.6 % of patients surveyed suffered from hypertension. Before carried out the intervention study, 48.2% of participants had an insufficient level of knowledge; after applied the educational program, 52.9% increase their knowledge passing to ¨Good¨ knowledge level.Conclusions: the implementation of the educational program made possible to increase the level of knowledge concerning COVID-19, so that its efficacy for preventing this infection in Primary Health Care it is effective.

Introduction: eye movement disorders are an important indicator for the diagnosis of certain neurodegenerative diseases. Electrooculography is the most widespread technique for measuring such eye movements. During the performance of the eye test, patients may forge unwanted head movements that add disturbances to the electrooculographic signal, modifying its morphological characteristic and, therefore, changing certain diagnostic parameters. Objective: to develop a method for the correction of the effect of the horizontal and angular head displacement by the electrooculographic signal. Method: It is detailed the use of a mathematical model for the correction of two types of artificial electrooculographic signals with different horizontal head movements at the Universidad de Oriente, from March 2021 to December 2021. Results: the behavior of the method used was evaluated qualitatively through its implementation in the signals generated artificially in MATLAB. Finally, the correction effects on the diagnostic parameters of the electrooculographic signal were characterized. Conclusions: the implemented method proved its validity for specific cases, in which it is possible to eliminate the errors caused by head displacement in two types of signals. The correction minimizes the error introduced in the uncorrected electrooculographic signal amplitude and keeps unchanged the other diagnostic parameters in absence of further analyses.

Introduction: osteoarthritis is a chronic degenerative joint disease, with an inflammatory component included, its characterized by degeneration and progressive loss of hyaline cartilage and subchondral bone and also for synovial tissue damage.Objective: to describe the clinical and epidemiological aspects of patients diagnosed with osteoarthritis at the Provincial Hospital of Zaire in the Republic of Angola, from September 2021 to September 2022. Method: a descriptive, longitudinal cohort study was carried out using the data gathered from the Department of Orthopedics and Traumatology of the institution. The universe consisted of 489 patients and the study sample consisted of n꓿167. Bivariate correlation tests were performed using the Pearson's correlation coefficient analysis. Results: the predominant age group was 61 to 70 years old (28.7%), with women sex as predominant (58.1%), with an evolution time of more than 5 years (35.9%), and the knee was the most affected joint (observed in 62 patients). A considerable positive correlation between the time of the disease evolution and the degree of disability was demonstrated using the Pearson's coefficient value (0.407), value that shows a great statistical significance. Conclusions: osteoarthritis is a degenerative disease of varied etiology that occurs at early ages, more frequently in the female sex associated with the knee joint, and there is a correlation between the time of evolution and the degree of disability produces by the disease.

Introducción: la COVID-19 trajo consigo múltiples afectaciones sobre todo en el ámbito de la salud. Estas se manifiestan progresivamente en quienes la padecen con relación a los síntomas presentados, que se hacen visibles a corto y largo plazo a nivel físico y mental. Objetivo:identificar las afectaciones físicas y psicológicas consecuencia de la COVID-19 en personas activas físicamente antes de la enfermedad, durante el periodo comprendido de enero a mayo de 2021.Método: se utilizó la metodología cualitativa de corte descriptivo-interpretativo. Se empleó para el estudio una muestra de 5 adultos de 27 a 66 años de edad originarios de Juchitán, Oaxaca, México, los cuales fueron seleccionados a partir de los siguientes criterios: haber sido portadores, el nivel de gravedad (leve/moderado) y haber realizado actividad física constante antes de padecer COVID-19. Las técnicas para el acopio de información aplicadas fueron: la entrevista y el cuestionario. Resultados: se evidenció una drástica disminución con relación a los componentes de la actividad física (tipo, frecuencia, intensidad y duración), así como la prevalencia de afectaciones psicológicas: estrés, depresión, ansiedad y miedo. En cuanto a las afectaciones a nivel físico se destacó la pérdida de peso y la fatiga (100 %), seguido por la caída del cabello (80 %) en los estudiados.Conclusiones: la disminución de la actividad física es consecuencia de la propia enfermedad, mientras que las afectaciones psicológicas son resultado de la incertidumbre que genera el padecimiento.

Introduction: COVID-19 caused healthcare professional workers have faced the pandemic on the frontline at the risk of being infected with the virus. Despite the low mortality rate at present and the low presence of patients with COVID-19 in health care centers, the application of a fourth booster dose has generated different positions among several countries. Objective: to determine whether personnel considered being at high risk of vulnerability in the city of Santo Domingo de los Colorados, Ecuador, have favorable intentions for receiving the fourth booster dose of the COVID-19 vaccine. Method: a quantitative study of correlational scope and cross-sectional design was developed. A questionnaire consisting of 16 questions measured the following variables: risk of infection, perceived knowledge of the vaccine, confidence in the vaccine and intention to be vaccinated; this questionnaire was applied to 375 participants. Statistical analyses were developed using the microsoft Excel spreadsheed and Statistical Packagefor Social Sciences 21 (SPSS 21).Results: statistical analyses showed that the risk of infection (β=0.178**), perceived knowledge about the vaccine (β=0.218**) and confidence about the vaccine (β=0.192**) are significantly correlated with the intention to be fully vaccinated, thus showing the need for a fourth booster dose by vulnerable sectors. Conclusion: this is the first research that presents results regarding the intention to vaccinate vulnerable people and highlights the intention to access a fourth booster dose.

Introduction: the decrease in glomerular filtration rate in older adults’ patients with diabetic and hypertensive problems is a consequence of physiological factors to which are added some vascular changes associated with alterations produced by underlying chronic diseases. Objective: to characterize renal function in older adults’ patients with diabetic and hypertensive problems attended at the Family Doctor's Office No. 4, Policlínico Docente "Ángel Alfonso Ortiz Vázquez", Manzanillo, Granma.Method: a descriptive, retrospective study was carried out in 2020 to determine the renal function in 249 older adults with diabetic and hypertension problems. The Cockcroft-Gaulty formula was used. The following variables extracted from the medical records were used: diagnosis of diabetes mellitus, diagnosis of hypertension, age, sex, weight and creatinine text. Results: male sex predominated (52.2 %). The mean age range, between 60 and 87 years, was 68.9 ± 7.3. The minimum glomerular filtration rate was 27.5 ml/min/1.73 m2, and the maximum was 143.7 ml/min/1.73 m2, the mean rate in these patients was 69.2 ± 18.7 ml/min/1.73 m2. For male was 71.4 ± 19.0 ml/min/1.73 m2 and 66.8 ± 18.2 ml/min/1.73 m2 for female. Hypertension predominated (94.4%) over diabetes mellitus (41.8%). The glomerular filtration rate in hypertensive patients (29.7 %) was less than 60 ml/min/1.73 m2. Conclusions: a third of patients with diabetic and hypertension had decreased in glomerular filtration rate, and this decrease was associated with increasing age.