Simultaneous removal of nutrients and biological pollutants via specialty absorbents in a water filtration system for watershed remediation.

To investigate watershed remediation within a Total Maximum Daily Load program, this study examined the field-scale filtration performance of two specialty absorbents. The goal was to simultaneously remove nutrients and biological pollutants along Canal 23 (C-23) in the St. Lucie River Basin, Florida. The filtration system installed in the C-23 river corridor was equipped with either clay-perlite with sand sorption media (CPS) or zero-valent iron and perlite green environmental media (ZIPGEM). Both media were formulated with varying combinations of sand, clay, perlite, and/or recycled iron based on distinct recipes. In comparison with CPS, ZIPGEM exhibited higher average removal percentages for nutrients. Findings indicated that ZIPGEM could remove total nitrogen up to 49.3%, total Kjeldahl nitrogen up to 67.1%, dissolved organic nitrogen (DON) up to 72.9%, total phosphorus up to 79.6%, and orthophosphate up to 73.2%. Both ZIPGEM and CPS demonstrated similar efficiency in eliminating biological pollutants, such as E. coli (both media exhibiting an 80% removal percentage) and chlorophyll a (both media achieving approximately 95% removal). Seasonality effects were also evident in nutrient removal efficiencies, particularly in the case of ammonia nitrogen; the negative removal efficiency of ammonia nitrogen from the fifth sampling event could be attributed to processes such as photochemical ammonification, microbial transformation, and mineralization of DON in wet seasons. Overall, ZIPGEM demonstrated a more stable nutrient removal efficiency than CPS in the phase of seasonal changes.

Latin-American Registry of Cardiovascular Disease and COVID-19: Final Results.

Background: Socioeconomic factors contribute to a more severe impact of COVID-19 in Latin American and Caribbean (LA&C) countries than in developed countries. Patients with a severe or critical illness can develop respiratory and cardiovascular complications. Objective: To describe a LA&C population with COVID-19 to provide information related to this disease, in-hospital cardiovascular complications, and in-hospital mortality. Methods: The CARDIO COVID-19-20 Registry is an observational, multicenter, prospective, and hospital-based registry of patients with confirmed COVID-19 infection that required in-hospital treatment in LA&C. Enrollment of patients started on May 01, 2020, and ended on June 30, 2021. Results: The CARDIO COVID-19-20 Registry included 3260 patients from 44 institutions of 14 LA&C countries. 63.2% patients were male and median age was 61.0 years old. Most common comorbidities were overweight/obesity (49.7%), hypertension (49.0%), and diabetes mellitus (26.7%). Most frequent cardiovascular complications during hospitalization or reported at discharge were cardiac arrhythmia (9.1%), decompensated heart failure (8.5%), and pulmonary embolism (3.9%). The number of patients admitted to the Intensive Care Unit (ICU) was 1745 (53.5%), and median length of their stay at the ICU was 10.0 days. Support required in ICU included invasive mechanical ventilation (34.2%), vasopressors (27.6%), inotropics (10.3%), and vasodilators (3.7%). Rehospitalization after 30-day post discharge was 7.3%. In-hospital mortality and 30-day post discharge were 25.5% and 2.6%, respectively. Conclusions: According to our findings, more than half of the LA&C population with COVID-19 assessed required management in ICU, with higher requirement of invasive mechanical ventilation and vasoactive support, resulting in a high in-hospital mortality and a considerable high 30-day post discharge rehospitalization and mortality.

Synergistic Integration Between Machine Learning and Agent-Based Modeling: A Multidisciplinary Review.

Agent-based modeling (ABM) involves developing models in which agents make adaptive decisions in a changing environment. Machine-learning (ML) based inference models can improve sequential decision-making by learning agents' behavioral patterns. With the aid of ML, this emerging area can extend traditional agent-based schemes that hardcode agents' behavioral rules into an adaptive model. Even though there are plenty of studies that apply ML in ABMs, the generalized applicable scenarios, frameworks, and procedures for implementations are not well addressed. In this article, we provide a comprehensive review of applying ML in ABM based on four major scenarios, i.e., microagent-level situational awareness learning, microagent-level behavior intervention, macro-ABM-level emulator, and sequential decision-making. For these four scenarios, the related algorithms, frameworks, procedures of implementations, and multidisciplinary applications are thoroughly investigated. We also discuss how ML can improve prediction in ABMs by trading off the variance and bias and how ML can improve the sequential decision-making of microagent and macrolevel policymakers via a mechanism of reinforced behavioral intervention. At the end of this article, future perspectives of applying ML in ABMs are discussed with respect to data acquisition and quality issues, the possible solution of solving the convergence problem of reinforcement learning, interpretable ML applications, and bounded rationality of ABM.

Physioprophylaxis post-stress test in soccer players: effects blood lactate concentrations

Abstract Objective: To determine the effects of physioprophylaxis (PP) on blood lactate (BL) concentrations after maximal incremental stress test, considering that this is the application of techniques in sports physiotherapy to reduce signs of muscle fatigue that can trigger injuries due to overload. Materials and Methods: Quantitative study, experimental type, longitudinal section in 12 university players. The group is divided into one control group (CG) with recovery at rest without PP and another experimental group (EG) to which PP is applied at the end of the test. Blood lactate is recorded with Accutrend Plus at the beginning of the test, (1) five minutes after finishing the test (2) and after the PP (3) at two different moments for intra-subject analysis. Results: The following data were obtained regarding blood lactate clearance, Moment 1: Without Plan (WoP) 4.86±1.4 and With Plan (WP) 8.85±1.25 (p<0.05), moment 2: (WoP) 5.6±1.76 and (WP) 7.8±1.3 (p<0.05) in mmol/L, and intra-subject: (WoP): 5.25±1.58; (WP): 8.35±1.33 (p<0.05). Conclusions: The clearance of lactate in the blood at 30 minutes post stress test in the EG is bigger than the CG, because they recovered with the physioprophylactic plan.

Resumen Objetivo: Determinar los efectos de la fisioprofilaxis (PP) sobre las concentraciones de lactato en sangre (BL) tras la prueba de esfuerzo incremental máximo, considerando que se trata de la aplicación de técnicas en fisioterapia deportiva para reducir los signos de fatiga muscular que pueden desencadenar lesiones por sobrecarga. Materiales y métodos: Estudio cuantitativo, tipo experimental, sección longitudinal en 12 jugadores universitarios. El grupo se divide en un grupo control (GC) con recuperación en reposo sin PP y otro grupo experimental (GE) al que se aplica PP al final de la prueba. El lactato sanguíneo se registra con Accutrend Plus al inicio de la prueba, (1) cinco minutos después de finalizar la prueba (2) y después de la PP (3) en dos momentos diferentes para el análisis intra-sujeto. Resultados: Se obtuvieron los siguientes datos con respecto al aclaramiento de lactato en sangre, Momento 1: Sin Plan (WoP) 4.86 ± 1.4 y Con Plan (WP) 8.85 ± 1.25 (p <0.05), Momento 2: (WoP) 5.6 ± 1.76 y (WP) ) 7,8 ± 1,3 (p <0,05) en mmol / L, e intra-sujeto: (WoP): 5,25 ± 1,58; (WP): 8,35 ± 1,33 (p <0,05). Conclusiones: El aclaramiento de lactato en sangre a los 30 minutos post prueba de esfuerzo en el GE es mayor que en el GC, debido a que se recuperaron con el plan fisioprofiláctico.

Collaborative Teaching plus (CT+): A Timely, Flexible, and Dynamic Course Design Implemented during Emergency Remote Teaching in an Introductory Biology Course.

Student-centered pedagogies promote student learning in college science, technology, engineering, and mathematics (STEM) classrooms. However, transitioning to active learning from traditional lecturing may be challenging for both students and instructors. This case study presents the development, implementation, and assessment of a modified collaborative teaching (CT) and team-based learning (TBL) approach (CT plus TBL, or CT+) in an introductory biology course at a Minority-Serving Institution. A logic model was formulated depicting the various assessment practices with the culminating goal of improving the student learning experience. We analyzed qualitative and quantitative data based on students and instructors' behaviors and discourse, and student midsemester and end-of-semester surveys. Our findings revealed that the integration of multiple instructors allowed for knowledge exchange in blending complementary behaviors and discourse practices during class sessions. In addition, the frequent ongoing assessments and incorporation of student feedback informed the CT+ design during both in-person and emergency remote teaching. Furthermore, this course design could be easily adapted to a variety of STEM courses in higher education, including remote instruction.

Color removal for large-scale interbasin water transfer: Experimental comparison of five sorption media.

The increasing needs of drinking water due to population growth requires seeking for new tap water sources. However, these large-scale tap water sources are oftentimes abundant with dissolved natural organic matter (NOM), such as tannic acid issue causing color in water. If not removed at the source locations beforehand, NOM would impact coagulation and flocculation unit, and/or become precursors to prompt the production of disinfectant by-products after chlorination in drinking water treatment. This study focuses on developing and testing a suite of cost-effective, scalable, adaptable, and sustainable sorption media that can be implemented near the source locations of tap water as a pretreatment option to remove color for a long-distance interbasin transfer. Within the five tested sorption media, a media recipe of Zero-valent-Iron and Perlite based Green Sorption Media (ZIPGEM) with ingredients of 85% sand, 5% clay, 6% zero-valent-iron (ZVI) and 4% perlite by volume stood out as the best option for color removal. Findings showed that ZIPGEM can maintain a color removal of ∼77% for about 14,080 min, maintaining the effluent concentration below 40 Pt-Co units given the influent condition of 175 ± 10 Pt-Co units. A recovery on the adsorption capacity of ZIPGEM was observed around 40,000 min due to synergetic effects among several different ingredients of recycled ZVI, clay, sand, and perlites. ZIPGEM can be applied to industrial wastewater treatment for dye removal as well.

Green sorption media for the removal of perfluorooctanesulfonic acid (PFOS) and perfluorooctanoic acid (PFOA) from water.

This study investigated the removal of selected per- and polyfluoroalkyl substances (PFAS) from water via two green sorption media (IFGEM-7 and AGEM-2). Both selected green sorption media recipes contain sand (85-91%) and clay (3-4%), in addition to recycled iron (Fe) (5-7.5%) or aluminum (Al) (4.5% in AGEM-2 only). Batch and column studies were integrated and performed using the prescribed green sorption media recipes to determine their efficiencies in removing two most targeted PFAS, including perfluorooctanesulfonic acid (PFOS) and perfluorooctanoic acid (PFOA). In the batch test, while the removal efficiencies of PFOS ranged from 27 to 46% and 23 to 42%, those for PFOA ranged from 6 to 16% and 5 to 18% when using IFGEM-7 and AGEM-2, respectively. The higher removal of PFOS than PFOA observed in both IFGEM-7 and AGEM-2 batch tests could be attributed to higher media affinity for sulfonate groups of PFOS when compared to the carboxylate groups of PFOA. In the column study, the initial removal (within 1 h) by IFGEM-7 was greater than 99% for PFOS and 28% for PFOA. When comparing different dynamic adsorption models, it appears that the non-linear equations could better describe the trend of experimental data compared to the linear forms of the Modified Dose Response model. Life expectancy calculations, performed for demonstration purposes of field applications, suggested that if IFGEM-7 were to be applied in a downflow filter box to treat a hypothetical volume of 60,000 L of water during an emergency response, and it may last for 1506 h (62.8 d) and 4.2 h for a target removal of 80% of PFOS and PFOA, respectively.

Integration of machine learning classifiers and higher order tensors for screening the optimal recipe of filter media in stormwater treatment.

Filter media have oftentimes been used in fixed-bed column tests to examine their removal efficiencies for various pollutants, such as nutrients in stormwater runoff. With limited data sets from column studies, a response surface method (RSM), such as the Box-Behnken Design (BBD), and machine learning methods, can be used to transition from discrete mode assessment to continuous mode optimization, from which the key ingredients of filter media can be better synergized. In this study, similarly to drug discovery via chemometrics, RSM is used to generate meta-models and identify the optimum ratio between clay and iron-filings contents in Iron-filings-based Green Environmental Media (IFGEM) for nutrient removal in stormwater treatment. To achieve the continuous mode optimization, artificial neural network (ANN), deep belief network (DBN), and extreme learning machine (ELM) were selected as machine learning models to compare with BBD to explore the limited column data sets and improve the data science. While separate RSM can help realize the removal efficiencies of total nitrogen (TN), total phosphorus (TP), and ammonia based on varying ratios of clay and iron-filings contents in IFGEM, heterogeneous and inconsistent response surfaces generated from the four learners or classifiers (ANN, ELM, DBN, and BBD) complicate the selection of the final optimal recipe. The power of higher order singular value decomposition (HOSVD) helps synergize the optimal clay and iron filings matrixes of IFGEM in the context of continuous mode optimization via ANN, ELM, DBN, and BBD. With the aid of HOSVD, the optimal recipe for a holistic nutrient removal of TN, TP, and ammonia was determined to be 5% clay, 10% iron filings, 10% tire crumb, and 75% sand.

Adsorption thermodynamics and kinetics of Advanced Green Environmental Media (AGEM) for nutrient removal and recovery in agricultural discharge and stormwater runoff.

Recycled materials were used in three types of green sorption media for nutrient removal and possible recovery in high nutrient-laden agricultural discharge and stormwater runoff. The three types of green sorption media included in this comparative study were two new aluminum-based green environmental media (AGEM) and one existing iron-filings based green environmental media (IFGEM). The corresponding adsorption isotherm, thermodynamics, and kinetics models were simulated based on isotherm studies to determine their removal efficiency and potential for recovery of nitrate, phosphate, and ammonia when used as a soil amendment in crop fields or in a filter for water treatment. AGEM-2 exhibited the shortest contact time required to achieve nutrient removal above 80% with an average of 7 h, followed by AGEM-1 and IFGEM with 10.6 and 28 h, respectively. Natural soil was included as a control and exhibited minimal nutrient removal. Ammonia, which may be recovered as fertilizer for drop fields in a soil-water-waste nexus, was generated by all three green sorption media mixes, therefore indicating their potential for use as soil amendments in agricultural and forested land after engineering filter applications. The kinetics analysis indicated that nitrate adsorption follows pseudo-first-order kinetics, while phosphate adsorption follows pseudo-second-order kinetics. The Gibbs free energy indicated that most of the adsorption reactions proceeded as exothermic. Lastly, a few equilibrium models, including the Langmuir, Freundlich, First Modified Langmuir, Temkin, Jovanovic, and Elovich models, were ranked and three were selected for use with IFGEM, AGEM-1, and AGEM-2, respectively, as below: (1) Langmuir, (2) Freundlich, and (3) First Modified Langmuir, according to three indices.

The interaction of dissolved organic nitrogen removal and microbial abundance in iron-filings based green environmental media for stormwater treatment.

Nonpoint sources pollution from agricultural crop fields and urbanized regions oftentimes have elevated concentrations of dissolved organic nitrogen (DON) in stormwater runoff, which are difficult for microbial communities to decompose. The impact of elevated DON can be circumvented through the use of green sorption media, such as Biosorption Activated Media (BAM) and Iron-Filing Green Environmental Media (IFGEM), which, as integral parts of microbial ecology, can contribute to the decomposition of DON. To compare the fate, transport, and transformation of DON in green sorption media relative to natural soil (control), a series of fixed-bed columns, which contain natural soil, BAM, and two types of IFGEM, respectively, were constructed to compare nutrient removal efficiency under three distinct stormwater influent conditions containing nitrogen and phosphorus. The interactions among six microbial species, including ammonia-oxidizing bacteria, nitrite-oxidizing bacteria, complete ammonia oxidation (comammox) bacteria, anaerobic ammonium oxidation (anammox) bacteria, dissimilatory nitrate reduction to ammonium bacteria, and iron-reducing bacteria, were further analyzed from microbial ecology perspectives to determine the DON impact on nutrient removal in BAM and IFGEM. Natural soil was only able to achieve adequate DON transformation at the influent condition of lower nutrient concentration. However, the two types of IFGEM showed satisfactory nutrient removals and achieved greater transformation of DON relative to BAM when treating stormwater in all three influent conditions.

Comparative nitrogen removal via microbial ecology between soil and green sorption media in a rapid infiltration basin for co-disposal of stormwater and wastewater.

In this study, a rapid infiltration basin (RIB) designed as green infrastructure for co-disposal of wastewater effluent and stormwater runoff was retrofitted for sustainable groundwater recharge after nitrogen removal. For comparison of nitrogen removal efficiency via different filtration media, the RIB was divided into two sub-basins for different filtration processes. One sub-basin was filled with a native sandy soil with about 2-4% clay (Control RIB), and the other sub-basin was modified with Biosorption Activated Media (BAM) (BAM RIB), for the enhancement of microbial nitrogen removal. The two sub-basins accept an equal amount of excess reclaimed wastewater in non-storm periods, and stormwater during periodic storm events. The infiltrate in both the BAM RIB and the Control RIB eventually reaches the Upper Floridan Aquifer. The seven microbial species involved in this microbial ecology study are nitrite oxidizing bacteria (NOB), ammonia oxidizing bacteria (AOB), anaerobic oxidation of ammonium (anammox) bacteria, complete ammonia oxidizer (Comammox) bacteria, denitrifiers, dissimilatory nitrate reduction to ammonium (DNRA) and ammonia-oxidizing archaea (AOA). The population dynamics study was conducted with the aid of the quantitative polymerase chain reaction (qPCR) for the quantification of the microbial gene population in support of microbial ecology discovery. The qPCR results demonstrated the competition effect between AOA, AOB, and Comammox, the inhibition effect between NOB and DNRA with the presence of anammox, and the complementary effect due to an abundance of NOB and AOB in the microbial ecology. Although, competition between denitrifiers and DNRA was expected to impact population dynamics, both microbial species were found to be the most predominant in both control and BAM RIBs. Research findings indicate that the use of BAM RIB achieves significantly efficient nitrogen removal driven by complementary effects in the microbial ecology.

Copper impact on enzymatic cascade and extracellular sequestration via distinctive pathways of nitrogen removal in green sorption media at varying stormwater field conditions.

Nutrient removal efficiency in green sorption media such as biosorption activated media (BAM) for treating stormwater runoff can be heavily influenced either on a short- or long-term basis by varying field conditions of linear ditches due to the presence of copper in stormwater runoff. It is also noticeable that the linear ditch undergoes physical or mechanical impacts from the traffic compaction, chemical impact of carbon sources from the nearby farmland, and biological impact from potential animal activities (such as gopher tortoises, moles, and ants). In the nitrogen cycle, two denitrification pathways, the dissimilatory nitrate reduction to ammonia and common denitrification, are deemed critical for such assessment. A fixed-bed column study was set up to mimic different linear ditch field conditions for BAM applications and measure the effect of short-and long-term copper addition on microbial dynamics given the varying decomposition of dissolved organic nitrogen (DON). The findings confirm that, as the denitrifiers (in the second pathway) were the dominant species, their population continued to grow and maintain small-sized cells for extracellular sequestration under long-term copper impact. Furthermore, the study indicated that the ammonia oxidizer comammox was found in higher quantities than ammonia oxidizing bacteria or archaea. An enormous amount of DON was released during this process to bind the copper ion and reduce its toxicity as the enzymatic cascade effect appeared. In addition, the long-term copper exposure posed salient inhibitory effects on the microbial community regardless of varying field conditions in BAM. Short-term copper toxicity exerted an important but varying role in the enzymatic cascade effect over different linear ditch field conditions in BAM.

Evaluation of green sorption media blanket filters for nitrogen removal in a stormwater retention basin at varying groundwater conditions in a karst environment.

Removing excess nutrient from stormwater runoffs is necessary to protect the water quality of receiving water bodies such as rivers, lakes, springs, and groundwater aquifers. Silver Springs Springshed, located in the vicinity of Ocala, Florida, has received widespread attention from the local government and residents due to its long-term nutrient impact, which has resulted in eutrophication. Blanket filters containing Bio-sorption Activated Media (BAM) were implemented with different depths of the vadose zone in a stormwater retention basin. The design combined the interaction with groundwater as an innovative Best Management Practice can potentially boost the performance of nutrient removal. Selected storm runoffs were collected at multiple points that cover the runoff timeframe to determine the pollutant load. Infiltrating water samples were collected at various depths within BAM using lysimeters to validate the treatment effectiveness. Significant pollutant load reduction of nutrients was confirmed with highest 99% and 91% removal of nitrate and nitrite (NOx) and total nitrogen (TN) at the deep blanket filter (with more groundwater intrusion impacts) due to more effective denitrification and longer contact time. Yet the highest pollutant load reduction of 93% and 84% removal of NOx and TN was also observed at the shallow blanket filter (with less groundwater intrusion impacts). On the other hand, better pollutant load reduction of ammonia in the BAM layer was found at the shallow blanket filter presumably due to more available oxygen for nitrification.

Evaluación de la gestión de residuos peligrosos (respel) y sus implicaciones en el desarrollo sostenible de las actividades productivas en cinco municipios del departamento del quindío, colombia / Assessment of hazardous waste management (respel) and its implications for sustainable development of productive activities in five municipalities of the department of quindio, colombia

Objetivos: Revisar la normatividad de residuos peligrosos en Colombia, su aplicabilidad y reglamentación, en un departamento pequeño que tiene una reducida generación, con el fin de identificar los vacíos existentes y la aplicabilidad de la política ambiental nacional, así como un análisis DOFA en la aplicabilidad de la normatividad de residuos peligrosos en el departamento del Quindío, comprobando la gestión integral y sus implicaciones. Metodología: La revisión incluyó la revisión de la comprensión de la normatividad, así como la bibliografía usada en la formulación de la política, los casos exitosos en otros países y la realización de encuestas en el trabajo de campo a los generadores de residuos, con lo cual se obtuvo la información necesaria para evaluar la aplicación de la Política Nacional en el departamento del Quindío. Resultados: Se visibilizaron las realidades de los generadores de residuos peligrosos en los cinco municipios del Quindío frente a la normativa ambiental y la Política Nacional, se encontró que la normativa nacional excluye a este sector, toda vez que hace exigencias que son difíciles de cumplir, por tanto no se aplica la norma. Discusión: Actualmente, no se promueve a nivel regional y nacional, la gestión de residuos peligrosos ni las opciones que faciliten el cumplimiento de las normas específicas, sin poner en riesgo la sustentabilidad ambiental, la sostenibilidad económica y social de los generadores de residuos peligrosos en los cinco municipios del Quindío. Conclusiones: Como producto de la investigación, se propone un modelo de gestión de residuos peligrosos, con dos variables dependiendo del volumen y características de los residuos generados, que incluye el ajuste normativo, la asociatividad de los generadores, una modificación del marco tarifario (con base en la regulación de los parámetros críticos de recolección y transporte), y el acompañamiento de los sectores comprometidos con la sostenibilidad ambiental, principalmente con la capacitación, formación ambiental y fortalecimiento técnico referido al manejo de los residuos o desechos peligrosos (líquidos, gaseosos, sólidos), orgánicos (que pueden tener procesos de compostaje) e inorgánicos (que pueden ser utilizados como reciclado o reutilizados como logística reversa o inversa) y los inservibles. Existe un gran desafío para un país, en especial cuando éste se enmarca en compromisos de convenios internacionales, al no tener en cuenta la heterogeneidad de las regiones, en cuanto a las capacidades de gestión y eliminación adecuada de residuos.

Objectives: To review the regulations for hazardous waste in Colombia, its applicability and regulation, in a small Department that has a reduced generation in order to identify gaps, and the applicability of the national environmental policy, as well as a DAFO analysis in the applicability of the regulations of hazardous waste in the department of Quindío, checking integrated management and its implications. Methodology: The revision included a review of the understanding of the regulations, as well as the literature used in the formulation of the policy, the successful cases in other countries and surveys to waste generators in the field work, with the purpose of obtaining the information needed to evaluate the implementation of the National Policy in the Department of Quindío. Results: The realities of hazardous waste generators became visible in the five municipalities of Quindío against the environmental regulations and the National Policy. It was found that the national legislation excludes this sector since it makes demands that are difficult to fulfill, therefore the rule is not applied. Discussion: Currently, management of hazardous waste or options to facilitate the achievement of specific standards without compromising environmental, economic and social sustainability of the generators of hazardous waste in the five municipalities of Quindío is not promoted at the regional and national level. Conclusions: As a result of the research, a model of hazardous waste management is proposed with two variables depending on the volume and characteristics of waste generated including regulatory setting, the association of the generators, a modification of the rate structure (based on the regulation of critical collection and transport parameters), and the accompaniment of the sectors committed to environmental sustainability, mainly through training, environmental education and technical strengthening relative to the handling of residues or hazardous waste (liquid, gaseous, solids), organic (which may have composting processes) and inorganic (which can be used as recycled or reused as reverse or inverse logistics) and unusable. There is a great challenge for a country, especially when it is part of commitments to international conventions, when it does not take into account the heterogeneity of the regions in terms of management skills and proper waste disposal.

Actividad antibacteriana y citotoxicidad in vivo de extractos etanólicos de Bauhinia variegata L. (Fabaceae) / Antibacterial activity and in vivo cytotoxicity of ethanol extracts from Bauhinia variegata L. (Fabaceae)

Introducción: diversas investigaciones han identificado el potencial biológico de diferentes compuestos como flavonoides, taninos, esteroides, naftoquinonas y sesquiterpenoides presentes en el género Bauhinia. Se ha reportado para la especie Bauhinia variegata la presencia de flavonoides con propiedades antidiabéticas y antivirales; sin embargo, el estudio del potencial antibacterial y citotóxico in vivo es incipiente, tanto para compuestos de flavonoides como de alcaloides. Objetivo: determinar la actividad antibacteriana y citotóxica in vivo de los extractos alcaloidales de Bauhinia variegata L. Métodos: se aplicó cromatografía de columna para la extracción y el aislamiento de los alcaloides presentes en las hojas de B. variegata. Extractos y fracciones alcaloidales se evaluaron para determinar el potencial citotóxico por medio del bioensayo sobre "camarones de mar" (Artemia salina) y el potencial antibacterial sobre Escherichia coli por medio del método de difusión en disco (antibiograma por difusión). Resultados: se obtuvieron 6 compuestos depurados, a los cuales se les determinó la presencia del núcleo protoberberinico según espectrofotometría ultravioleta. En relación con el bioensayo sobre Artemia salina, el extracto crudo mostró menor toxicidad (CL50> 1 000 µg/mL), mientras que la fracción de los alcaloides totales y el compuesto CD1 mostró alta toxicidad (CL50< 500 µg/mL); contrario a lo evidenciado para el bioensayo antimicrobiano, porque no se presentaron halos de inhibición para los tratamientos con los extractos y compuestos utilizados. Conclusiones: la actividad citotóxica reportada se debe al efecto sinérgico del conjunto de metabolitos secundarios que pudieron evidenciarse en la planta y a los cuales también se les reconoce esta actividad (alcaloides y terpenos), que explica así la toxicidad mostrada por la fracción de los alcaloides totales.

Introduction: several research studies have identified the biological potential of different compounds such as flavonoids, tannins, steroids, naphtoquinones and sesquiterpenoid present in the genus Bauhinia. It has been reported for the species B. variegata the presence of flavonoids with anti-diabetic and antiviral properties, but the study of antibiotic and cytotoxic potential is just incipient for both flavonoid and alkaloid compounds. Objective: to determine the antibacterial and in vivo cytotoxic activity of alkaloid extracts from Bauhinia variegata L. Methods: column chromatography for extraction and isolation of alkaloids in B. variegata.leaves was performed. Alkaloid extracts and fractions were tested through bioassay for their cytotoxic potential on "brine shrimp" (Artemia salina) and the antibacterial potential on Escherichia coli through the disk diffusion method (antibiogram by diffusion). Results: six compounds were purified and measured the presence of the protoberberinic nucleus by means of UV spectrophotometry. Regarding Artemia salina bioassay, the crude extract (CE) showed less toxicity (LC50> 1000 µg/mL), whereas the fraction of the total alkaloid fraction (TA) and the CD1 compound showed high toxicity (LC50< 500 µg/mL). Unlike the evidence for the antimicrobial bioassay, no inhibition zones for treatment with the extracts and the compounds appeared. Conclusions: the reported cytotoxic activity is caused by the synergistic effect of all secondary metabolites that could occur in the plant, which were also associated with this activity (alkaloids and terpenes) that account for the toxicity shown by the total alkaloid fraction.

Testimonio de Colombia : En San Cayetano renace la esperanza

Este artículo da información general sobre la evacuación del pueblo San Cayetano (Colombia) para prevenir otra tragedia como la del Nevado del Ruiz, en la que murieron miles de personas por una inundación de lodo provocada por una erupción volcánica

A Colombian testimonial : In San Cayetano, hope springs new

This article gives general information about the evacuation of San Cayetano town (Colombia) to prevent other tragedy like the Nevado del Ruiz disaster, in which thousands had perished due to a massive mudslide precipitated by a volcanic eruption