Assessment of polluted soil remediation using bacterial community tolerance to heavy metals as an indicator

The assessment of remediation on metal-polluted soils is usually focused on total and/or bioavailable metal content. However, these chemical variables do not provide direct information about reductions in heavy metals pressure on soil microorganisms. We propose the use of bacterial communities to evaluate the efficiency of three remediation techniques: crushed mussel shell (CMS) and pine bark (PB) as soil amendments and EDTA-washing. A soil sample was polluted with different doses of Cu, Ni, and Zn (separately). After 30 days of incubation, the remediation techniques were applied, and bacterial community tolerance to heavy metals determined. If bacterial communities develop tolerance, it is an indicator that the metal is exerting toxicity on them. Soil bacterial communities developed tolerance to Cu, Ni, and Zn in response to metal additions. After remediation, bacterial communities showed decreases in bacterial community tolerance to Cu, Ni, and Zn for all remediation techniques. For Cu and Ni, soil EDTA-washing showed the greatest reduction of bacterial community tolerance to Cu and Ni, respectively, while for Zn the soil amendment with PB was the most effective remediation technique. Thus, bacterial community tolerance to heavy metals successfully detect differences in the effectiveness of the three remediation techniques.Ministerio de Economía y Competitividad | Ref. CTM2015-73422-JINMinisterio de Economía, Industria y Competitividad | Ref. RYC-2016-20411Región de Murcia | Ref. 21525/EE/21Xunta de Galicia | Ref. ED401A-2020/08

Dissolved organic matter as a confounding factor in the determination of pollution-induced community tolerance (PICT) of bacterial communities to heavy metals using the leucine incorporation method

PICT methodology using the leucine incorporation method (Leu-PICT) is useful for assessing heavy metal contamination in soils. First, bacterial community is exposed to metal in the soil (selection phase), developing tolerance if metal exerts toxicity. Secondly, in detection phase, bacterial suspensions are obtained, and tolerance is quantified by a second exposition of bacterial community to the metal using Leu-PICT methodology. However, during detection phase when Leu-PICT is performed, some characteristics of bacterial suspensions may change metal bioavailability. We assess the influence of dissolved organic matter (DOM) in bacterial suspensions, as humic acids (HA), on Leu-PICT determination to Cr, Cu, Ni, Pb and Zn. Results showed that the presence of HA in bacterial suspensions causes underestimations of bacterial community tolerance to Cr (increasing Cr toxicity), and overestimations of bacterial community tolerance to Cu, Ni, Pb, and Zn (reducing metal toxicity). In addition, the magnitude of these overestimations was different depending on the metal.Xunta de Galicia | Ref. ED401A-2020/084Ministerio de Economía y Competitividad | Ref. CTM2015-73422-JINFinanciado para publicación en acceso aberto: Universidade de Vigo/CISU

El comportamiento responsable medioambiental de los habitantes de Tenerife según su interés en la información

El interés en la búsqueda de información medioambiental por parte de la población es una cuestión poco estudiada hasta ahora, pero de gran importancia puesto que actualmente estamos viviendo una situación ambiental bastante perjudicada. Ante este hecho, nuestro estudio pretende determinar las variables de la Teoría del Comportamiento Planificado que hacen variar el comportamiento responsable del individuo, centrándonos en el interés en la información, con el objetivo de explicar el comportamiento responsable de los habitantes de Tenerife. Para llevar a cabo esta investigación, se ha revisado la literatura, y hemos recogido información mediante cuestionarios realizados a 1.439 residentes. Una vez que hemos obtenido los datos y analizado los resultados, estos muestran que cuanto mayor sea el interés de los individuos en buscar información medioambiental, mayor comportamiento responsable tendrán, por lo que es importante crear más formatos de información especializados en esta temática, que conciencien en mayor medida a los individuos.The interest in the search for environmental information by the population is a question that has not been studied much until now, but it is of great importance since we are currently experiencing a rather damaged environmental situation. In view of this fact, our study aims to determine the variables of the Theory of Planned Behaviour that vary the responsible behaviour of the individual, focusing on the interest in information, with the aim of explaining the responsible behaviour of the inhabitants of Tenerife. To carry out this research, we have reviewed the literature, and we have collected information through questionnaires made to 1,439 residents. Once we have obtained the data and analyzed the results, they show that the greater the interest of individuals in seeking environmental information, the greater the responsible behavior they will have, so it is important to create more specialized information formats on this subject, which raise awareness among individual

Estimation of baseline levels of bacterial community tolerance to Cr, Ni, Pb, and Zn in unpolluted soils, a background for PICT (pollution-induced community tolerance) determination

The PICT method (pollution-induced community tolerance) can be used to assess whether changes in soil microbial response are due to heavy metal toxicity or not. Microbial community tolerance baseline levels can, however, also change due to variations in soil physicochemical properties. Thirty soil samples (0–20 cm), with geochemical baseline concentrations (GBCs) of heavy metals and from five different parent materials (granite, limestone, schist, amphibolite, and serpentine), were used to estimate baseline levels of bacterial community tolerance to Cr, Ni, Pb, and Zn using the leucine incorporation method. General equations (n = 30) were determined by multiple linear regression using general soil properties and parent material as binary variables, explaining 38% of the variance in log IC50 (concentration that inhibits 50% of bacterial growth) values for Zn, with 36% for Pb, 44% for Cr, and 68% for Ni. The use of individual equations for each parent material increased the explained variance for all heavy metals, but the presence of a low number of samples (n = 6) lead to low robustness. Generally, clay content and dissolved organic C (DOC) were the main variables explaining bacterial community tolerance for the tested heavy metals. Our results suggest that these equations may permit applying the PICT method with Zn and Pb when there are no reference soils, while more data are needed before using this concept for Ni and Cr.This study has been funded by the Spanish Ministry of Economy and Competitiveness through the project CTM2015-73422-JIN (FEDER Funds). David Fernández-Calviño holds a Ramón y Cajal contract (RYC-2016–20411) fnanced by the Spanish Ministry of Economy, Industry and Competitiveness. Claudia CampilloCora holds a predoctoral fellowship fnanced by Xunta de Galicia (ED481A-2020/084). Diego Soto-Gómez was supported by a postdoctoral fellowship from the Spanish Ministry of Education “Juan de la Cierva Formación (FJC2019-039176-I).

Didactic proposal for critical intertextual reading of expository texts with children of 5th grade of the Integrated Institute of San Bernardo de Floridablanca

El presente trabajo tuvo como propósito diseñar una propuesta didáctica basada en la lectura de textos expositivos para el fortalecimiento de la lectura crítico – intertextual de los niños de quinto de primaria del instituto Integrado de San Bernardo de Floridablanca -Santander, la pregunta problema del estudio fue: ¿Cómo fortalecer la lectura crítico intertextual de textos expositivos con niños de 5° primaria del Instituto Integrado San Bernardo? La metodología del estudio fue de enfoque cualitativo con diseño etnográfico, el escenario donde se desarrolló la investigación fue en el Instituto Integrado San Bernardo y participaron en el estudio 38 estudiantes del grado quinto de primaria de una institución educativa pública de Floridablanca, además participaron los docentes de básica primaria. Las técnicas de recolección de información utilizadas fueron las siguientes: grupo focal, la muestra de participantes, y la entrevista. Según los resultados obtenidos en el estudio se diseñó la estrategia para fortalecer el proceso lector de los estudiantes de quinto grado, como producto del análisis del estudio se construyeron cuatro sesiones de lectura cada una con estrategias de comprensión durante todo el proceso lector a través de una secuencia didáctica.CAPÍTULO I. PLANTEAMIENTO DEL PROBLEMA CAPÍTULO II. MARCO TEÓRICO CAPÍTULO III. METODOLOGÍA CAPÍTULO IV. RESULTADOS CAPÍTULO V CONCLUSIONES Bibliografía AnexosMaestríaThis project has the goal to design a didactic proposal based on the expository texts for improvement of a critical intertextual reading of the children who are fifth graders of the Instituto Integrado San Bernardo of Floridablanca. The problema cuestión was “¿How does a didactical proposal that involve expository texts, allows the improvement of a critical intertextual Reading? The methodology of investigation was with qualitative approach with etnographic design. The Instituto Integrado San Bernardo was the place where the investigation was done and thirty eight students of fifth graders participated. They are from a public school of Floridablanca. The other teacher of primary also cooperated. The next are the tecniques of data collection for the information: focal group, the simple of participants and the interview. Acording to the results of the research, it was designed the strategy to improve the Reading process of the analisys of the study, four sesions of Reading were built, each one with its strategies of comprehension during the whole reading process through of a didatic squence

The RNA-binding protein RBP33 dampens non-productive transcription in trypanosomes

In-depth analysis of the transcriptomes of several model organisms has revealed that genomes are pervasively transcribed, giving rise to an abundance of non-canonical and mainly antisense RNA polymerase II-derived transcripts that are produced from almost any genomic context. Pervasive RNAs are degraded by surveillance mechanisms, but the repertoire of proteins that control the fate of these non-productive transcripts is still incomplete. Trypanosomes are single-celled eukaryotes that show constitutive RNA polymerase II transcription and in which initiation and termination of transcription occur at a limited number of sites per chromosome. It is not known whether pervasive transcription exists in organisms with unregulated RNA polymerase II activity, and which factors could be involved in the process. We show here that depletion of RBP33 results in overexpression of similar to 40% of all annotated genes in the genome, with a marked accumulation of sense and antisense transcripts derived from silenced regions. RBP33 loss does not result in a significant increase in chromatin accessibility. Finally, we have found that transcripts that increase in abundance upon RBP33 knockdown are significantly more stable in RBP33-depleted trypanosomes, and that the exosome complex is responsible for their degradation. Our results provide strong evidence that RBP33 dampens non-productive transcription in trypanosomes

Increased markers of cardiac vagal activity in leucine-rich repeat kinase 2-associated Parkinson's disease.

PurposeCardiac autonomic dysfunction manifests as reduced heart rate variability (HRV) in idiopathic Parkinson's disease (PD), but no significant reduction has been found in PD patients who carry the LRRK2 mutation. Novel HRV features have not been investigated in these individuals. We aimed to assess cardiac autonomic modulation through standard and novel approaches to HRV analysis in individuals who carry the LRRK2 G2019S mutation.MethodsShort-term electrocardiograms were recorded in 14 LRRK2-associated PD patients, 25 LRRK2-non-manifesting carriers, 32 related non-carriers, 20 idiopathic PD patients, and 27 healthy controls. HRV measures were compared using regression modeling, controlling for age, sex, mean heart rate, and disease duration. Discriminant analysis highlighted the feature combination that best distinguished LRRK2-associated PD from controls.ResultsBeat-to-beat and global HRV measures were significantly increased in LRRK2-associated PD patients compared with controls (e.g., deceleration capacity of heart rate: p = 0.006) and idiopathic PD patients (e.g., 8th standardized moment of the interbeat interval distribution: p = 0.0003), respectively. LRRK2-associated PD patients also showed significantly increased irregularity of heart rate dynamics, as quantified by Rényi entropy, when compared with controls (p = 0.002) and idiopathic PD patients (p = 0.0004). Ordinal pattern statistics permitted the identification of LRRK2-associated PD individuals with 93% sensitivity and 93% specificity. Consistent results were found in a subgroup of LRRK2-non-manifesting carriers when compared with controls.ConclusionsIncreased beat-to-beat HRV in LRRK2 G2019S mutation carriers compared with controls and idiopathic PD patients may indicate augmented cardiac autonomic cholinergic activity, suggesting early impairment of central vagal feedback loops in LRRK2-associated PD