Search

Mining affects the environment, particularly through the persistence of accumulation of tailings materials; this is aggravated under tropical climatic conditions, which favours the release of potentially toxic elements (PTEs) bioavailable to the local flora and fauna and supposing a risk to human health. The Remance gold mine (Panamá), exploited intermittently for more than 100 years, and has remained derelict for over 20 years. Within the area live farmers who carry out subsistence agriculture and livestock activities. The objective of this study has been to study the transference of PTEs in the local agricultural soil-plants system, with the goal of identifying their bioavailability to perform a human risk assessment. The results obtained of the Bioaccumulation coefficient in local plants show very weak to strong absorption of As (−1) and plants (16.9 mg kg−1) the concentrations exceed the maximum authorised value in animal nutrition for ruminants (10 mg kg−1). The risk to human health for edible plants exceeds the non-carcinogenic risk for rice, corn, cassava, and tea leaves for Sb (HQ 19.450, 18.304, 6.075, 1.830, respectively), the carcinogenic risk for Cu (CR = 2.3 × 10–3, 7.7 × 10 −4, 1.1 × 10–3, 1.0 × 10–3, respectively), and the carcinogenic risk for As in rice, corn and tea leaves (CR = 8 × 10–5, 3 × 10–5, 3 × 10–5, respectively). Urgent measures are needed to alleviate these effects.

This current work shows the experience that was gotten in the education from a point of view in gender quality about the developing of the Certification Program in Computer working skills, according to the syllabus called Innovacion del ModeloEducativoInstitucional, IMEI (in English, Innovation of Institutional Educative Model) that is taught it in Universidad Autonoma de Campeche. Those skills are considered as basic skills for taking resolutions in responsible, knowledgeable and autonomous ways, which are based on respect and dignity of the human beings. All of them, because of expecting to value the plurality of identities and the living ways for the exercising of the responsible and tolerant citizenship to prevent the violence. This is a description research that expects to determine the context and educational factors, which works in the acquisition of those technological skills. The final results show the students are achiving successfully with that action program, encouraging the gender quality, developing, progress and comfort of the educative community and the society. &nbsp

BackgroundCOVID-19 pandemic has impacted lives globally. While COVID-19 did not discriminate against developed or developing nations, it has been a significant challenge for third world countries like Honduras to have widespread availability of advanced therapies. The concept of early treatment was almost unheard-of when early outpatient treatment with repurposed drugs in Latin American countries showed promising results. One such drug is fluvoxamine, that has shown tremendous potential in two major studies, following which fluvoxamine was added to the standard of care in Honduras.MethodsThis is a prospective observational study performed at the Hospital Centro Médico Sanpedrano (CEMESA) in San Pedro Sula, Cortes, Honduras in the COVID-19 outpatient clinic. All patients fifteen years of age or older, with mild or moderate signs and symptoms of COVID-19, and a positive SARS-CoV-2 antigen or Reverse Transcription Polymerase Chain Reaction (RT-PCR) were included in the study and prescribed fluvoxamine. Cohort of patients who decided to take fluvoxamine were compared to the cohort who did not take fluvoxamine for mortality risk and risk of hospitalization as primary endpoints. Patient were monitored for 30 days with first follow up at 7 days and second follow up at 10-14 days of symptom onset. Categorical variables were compared by Pearson Chi-square test. The Odds ratio was calculated using univariate and multivariate logistic regression. Continuous variables were compared by t-test and Wilcoxon rank-sum tests.ResultsOf 657 total COVID-19 cases, 594 patients took fluvoxamine and 63 did not. A total of five patients (0.76 percent) died, of which only one death occurred in the fluvoxamine group. Patients who did not receive fluvoxamine had a significantly higher mortality (OR 24, p0.005, CI 2.6 to 233.5). Odds ratio of hospitalization in patients who did not take fluvoxamine was 2.38 (30 vs 10 hospitalizations, p 0.040, CI 1.04-5.47). The odds ratio of requiring oxygen in patients in the non-fluvoxamine group was 5.08 (pConclusionThe results of our study suggest lowers odds of mortality and hospitalization in patients who took fluvoxamine vs fluvoxamine non-takers. Non-fluvoxamine group had higher odds of oxygen requirement than fluvoxamine group as well.

The evolution of the writing skill is closely linked to ICT, increasing the need to make its teaching a meaningful experience in the digital age. The aim of this study was to analyze students’ experiences in a writing task developed on Edublogs to identify elements of task design contributing to a meaningful experience online. The participants were 27 English Teaching students in a first-year composition course at the University of Costa Rica during the first semester of 2021. The study followed a Classroom Action Research design. The students wrote five blog entries. However, only the last entry, a reflection, was analyzed for the study. An open coding method was implemented, through which four categories that impact instructional design of writing tasks were identified: personal connection, engagement, ICT, and applicability. The study concludes with a series of recommendations that can positively impact students’ performance in writing courses supported by ICT.

Detrusor pressure-volume relationship evaluation by urodynamics provides useful clinical information; however, it is invasive, and requires specific installations. An alternative technique proposed by our research group is the electrical bioimpedance (BI) which is an easily performed and non-invasive method. In this work, we assess the relationship between BI and detrusor bladder pressure in adults with neurogenic lower urinary tract dysfunction.A prospective observational study was conducted. 20 patients (11 females and 9 male) previously diagnosed with neurogenic bladder were included. All participants underwent simultaneously a urodynamic evaluation (UDS) and BI determination, and both examination signals were recorded and subjected to Shapiro-Wilks statistical test. A correlational statistical test was used to compare the pressure parameters (detrusor, vesical and abdominal) with their respective BI determinations. Subsequently, a linear regression test was performed to evaluate the concordance between BI and their respective pressure values.From the 20 correlations, between detrusor bladder pressure (PDET) and abdominal bioimpedance determinations (ZABD), obtained for all participants, 16 evidenced significant results over 90% (p 0.05).A significantly high correlation between abdominal bioimpedance determinations and the detrusor bladder pressures was evidenced. These results should be confirmed in a larger group of participants.

RESUMEN Las especies autóctonas que habitan las cuencas hídricas del Paraguay se reproducen en medios acuáticos controlados a través de la inducción hormonal, la cual se realiza en laboratorios con diferentes técnicas y protocolos. Hasta el presente se ha utilizado la técnica de extrusión para el desove y producción de alevines en los centros de cría de las especies de importancia económica. El presente trabajo consistió en la implementación del sistema automatizado de desove y fertilización utilizando al pacú (Piaractus mesopotamicus) en etapa de maduración en estanques. El objetivo fue evaluar el sistema con dicha especie a través del desove, fertilización y horas grado. El mismo consistió en 3 unidades conectadas mediante tuberías; de modo que los huevos fertilizados sean transportados automáticamente desde el estanque de desove a la red de incubación, y las larvas eclosionadas se transportan desde la red de incubación al estanque de cría (creado por Fu- Guang Liu en Taiwán), en el trabajo se utilizaron progenitores de pacú; 51 hembras (3,2 kg - 3,7 kg) y 122 machos (2,6 Kg -2,7 kg). El desove osciló entre el 96% y el 100%, siendo la fertilización de entre el 61% al 76.6%, y las horas grado fueron de 174 a 270. La presente investigación demostró que el sistema automatizado de desove y fertilización puede ser utilizado en la obtención de alevines de pacú criados en cautiverio , existiendo suficientes evidencias de que la utilización del sistema beneficia la sobrevivencia y la reutilización de las matrices generándose mejores resultados. ABSTRACT The native species that inhabit the watersheds of Paraguay reproduce in controlled aquatic environments through hormonal induction, which is carried out in laboratories with different techniques and protocols. Until now, the extrusion technique has been used for the spawning and production of fingerlings in the breeding centers of species of economic importance. The present work consisted in the implementation of the automated spawning and fertilization system using the pacú (Piaractus mesopotamicus) in the maturation stage in ponds. The objective was to evaluate the system with this species through spawning, fertilization and degree hours. It consisted of 3 units connected by pipes; so that the fertilized eggs are automatically transported from the spawning pond to the incubation net, and the hatched larvae are transported from the incubation net to the rearing pond (established by Fu- Guang Liu in Taiwan), in the work wast used pacu parents; 51 females (3.2 kg - 3.7 kg) and 122 males (2.6 kg -2.7 kg). Spawning ranged between 96% and 100%, fertilization being between 61% and 76.6%, and degree hours were from 174 to 270. This research showed that the automated spawning and fertilization system can be used to obtain pacu fingerlings raised in captivity, there being sufficient evidence that the use of the system benefits the survival and reuse of the broodstock, generating better results.

The supply of water to populations is a basic need that has been threatened more frequently in recent years due to climate change, which renders seeking other sources of water essential. The hydrochemistry of the groundwater of the aquifer located in the UTP Tocumen was characterized by previous research to determine its possible use as a source of drinking water and irrigation water. The objective of this study is to characterize the soil and rock hosting the aquifer to acquire more information about them with a view to possibly exploit an alternative source of drinking water. To this end, a 10-m-depth survey was conducted to obtain soil and rock samples from the area, and to characterize geotechnical and geochemical parameters. 2D electrical resistivity tomography was used to create a lithological model of the aquifer and to correlate the data. Soil is residual of the technosol type, considered permeable with a transmissivity level that favors rainwater infiltration, followed by the soil–rock interface, where rock is weathered. It´s followed by a sedimentary rock corresponding to marly siltstones with a certain degree of tectonic fractures that allow water infiltration and its accumulation in the rocks, constituting the aquifer. The 2D electrical resistivity suggests two water accumulations: a superficial and a deep one. There was a good correlation between the aquifer water’s chemistry and the rock geochemistry., El abastecimiento de agua a las poblaciones es una necesidad básica que se ha visto amenazada con mayor frecuencia en los últimos años debido al cambio climático, lo que hace imprescindible buscar otras fuentes de agua. Se caracterizó la hidroquímica del agua subterránea del acuífero ubicado en la UTP Tocumen mediante investigaciones previas para determinar su posible aprovechamiento como fuente de agua potable y agua de riego. El objetivo de este estudio es caracterizar el suelo y la roca que alberga el acuífero para adquirir más información sobre ellos con miras a la posibilidad de explotar una fuente alternativa de agua potable. Para ello, se realizó un sondeo de 10 m de profundidad para obtener muestras de suelos y rocas de la zona, y caracterizar parámetros geotécnicos y geoquímicos. Se utilizó tomografía de resistividad eléctrica 2D para crear un modelo litológico del acuífero y correlacionar los datos. El suelo es residual del tipo tecnosol, considerado permeable con un nivel de transmisividad que favorece la infiltración del agua de lluvia, seguido de la interfase suelo-roca, donde la roca se meteoriza. Le sigue una roca sedimentaria correspondiente a limolitas margosas con cierto grado de fracturas tectónicas que permiten la infiltración del agua y su acumulación en las rocas, constituyendo el acuífero. La resistividad eléctrica 2D sugiere dos acumulaciones de agua: una superficial y otra profunda. Hubo una buena correlación entre la química del agua del acuífero y la geoquímica de la roca. Le sigue una roca sedimentaria correspondiente a limolitas margosas con cierto grado de fracturas tectónicas que permiten la infiltración del agua y su acumulación en las rocas, constituyendo el acuífero. La resistividad eléctrica 2D sugiere dos acumulaciones de agua: una superficial y otra profunda. Hubo una buena correlación entre la química del agua del acuífero y la geoquímica de la roca. Le sigue una roca sedimentaria correspondiente a limolitas margosas con cierto grado de fracturas tectónicas que permiten la infiltración del agua y su acumulación en las rocas, constituyendo el acuífero. La resistividad eléctrica 2D sugiere dos acumulaciones de agua: una superficial y otra profunda. Hubo una buena correlación entre la química del agua del acuífero y la geoquímica de la roca.

No hay resúmenes disponibles. Investigaciones UCA, Año. 1, Vol. 1, 2019-2020: 380-383.

Epigenetic mechanisms such as histone acetylation and deacetylation participate in regulation of the genes involved in encystation of Entamoeba invadens. However, the histones and target residues involved, and whether the acetylation and deacetylation of the histones leads to the regulation of gene expression associated with the encystation of this parasite, remain unknown. In this study, we found that E. invadens histone H4 is acetylated in both stages of the parasite and is more highly acetylated during the trophozoite stage than in the cyst. Histone hyperacetylation induced by Trichostatin A negatively affects the encystation of E. invadens, and this inhibition is associated with the downregulation of the expression of genes implicated in the synthesis of chitin, polyamines, gamma-aminobutyric acid pathways and cyst wall proteins, all of which are important in the formation of cysts. Finally, in silico analysis and activity assays suggest that a class I histone deacetylase (EiHDAC3) could be involved in control of the expression of a subset of genes that are important in several pathways during encystation. Therefore, the identification of enzymes that acetylate and/or deacetylate histones that control encystation in E. invadens could be a promising therapeutic target for preventing transmission of other amoebic parasites such as E. histolytica, the causative agent of amoebiasis in humans.

El objetivo de este artículo es presentar una serie de reflexiones sobre algunas de las condiciones que hacen posible la experiencia escolar, entendiendo la Escuela como una cuestión de interés público donde se media la relación entre las nuevas generaciones y el mundo, producto de siglos de experiencias culturales. Para ello, se revisaron tres textos relevantes: La crisis en la educación, de Hannah Arendt, Pedagogía: el deber de resistirde Philippe Meirieu y En defensa de la escuela. Una cuestión pública, de Maarten Simons y Jan Masschelein. Aprovechando la contingencia sanitaria producto de la pandemia asociada al Covid-19, es un momento oportuno para retomar algunas preguntas fundamentales sobre aquello que da sentido a esta institución que llamamos Escuela.

The Remance gold mine, in Veraguas (central Panama), had its last mining operation in 1999, using the cyanidation process for Au separation. As a result of this activity, three waste tailings were exposed to the weather, in addition to mine dumps and the open pit mining areas. Currently the area is inhabited by peasants who develop subsistence agriculture and livestock. Therefore, the objective of this study has been to evaluate the environmental and human health risks that this area represents. The total concentrations of potentially toxic elements (PTEs) such as As, Cu, Zn, Ba, Sb and Hg were determined in mining process areas, surrounding soils and edible and inedible plants in the area; in addition to the cyanide species and the enzymatic activity by dehydrogenase (DHA) in soils. The accumulated contamination index (PLI) and potential ecological risk (RI) were calculated, the carcinogenic (CR) and non-carcinogenic (HQ) risk to human health represented by soils and edible plants was estimated.Regarding the degree of contamination, it is observed that the contamination is considerable in the tailings and the sediments of the pithead, and it spreads to the surroundings mainly in the sediments of the streams and their terraces, and, to a lesser degree, to the soils around it, showing that the main route of dissemination is through runoff; the same trend is followed by the potential ecological risk, being extreme in the sediments of the pithead, serious in the tailings and terrace sediments, high in the stream sediments and medium in the surrounding soils. The enzymatic activity by DHA tells us that the health of the surrounding soils is better than that of the stream sediments and terrace sediments, but less than in other sites affected by mining activity in Spain. Cyanide species are linked to DHA and this in turn is favoured by organic matter (OM). On the other hand, it was observed that cyanide elutes from the tailing’s piles in a complex cyanide way, favouring the transport of PTEs associated with it to the stream sediments.Regarding the risks to human health in soils, As and Cu concentrations exceed the limits for non-carcinogenic and carcinogenic risk in both children and adults, with the residential scenario being the worst scenario, and for adults also the agricultural scenario. In edible plants such as rice, corn, cassava and tea leaves, Sb exceeds the limit for non-carcinogenic risk, and Cu and As for carcinogenic risk. Due to the potential ecological and human health risks that the area represents, actions must be taken to reduce them.Keywords: potentially toxic elements (PTEs), gold mine, risk assessment, edible plants, human health.