Nitrogen loss in coastal sediments driven by anaerobic ammonium oxidation coupled to microbial reduction of Mn(IV)-oxide.

Coastal sediments play a central role in regulating the amount of land-derived reactive nitrogen (Nr) entering the ocean, and their importance becomes crucial in vulnerable ecosystems threatened by anthropogenic activities. Sedimentary denitrification has been identified as the main sink of Nr in marine environments, while anaerobic ammonium oxidation with nitrite (anammox) has also been pointed out as a key player in controlling the nitrogen pool in these locations. Collected evidence in the present work indicates that the microbial biota in coastal sediments from Baja California (northwestern Mexico) has the potential to drive anaerobic ammonium oxidation linked to Mn(IV) reduction (manganammox). Unamended sediment showed ammonification, but addition of vernadite (δMnO2 with nano-crystal size ∼15 Å) as terminal electron acceptor fueled simultaneous ammonium oxidation (up to ∼400 µM of ammonium removed) and production of Mn(II) with a ratio ∆[Mn(II)]/∆[NH4+] of 1.8, which is very close to the stoichiometric value of manganammox (1.5). Additional incubations spiked with external ammonium also showed concomitant ammonium oxidation and Mn(II) production, accounting for ∼30 % of the oxidized ammonium. Tracer analysis revealed that the nitrogen loss associated with manganammox was 4.2 ± 0.4 µg 30N2/g-day, which is 17-fold higher than that related to the feammox process (anaerobic ammonium oxidation linked to Fe(III) reduction, 0.24 ± 0.02 µg 30N2/g-day). Taxonomic characterization based on 16S rRNA gene sequencing revealed the existence of several clades belonging to Desulfobacterota as potential microorganisms catalyzing the manganammox process. These findings suggest that manganammox has the potential to be an additional Nr sink in coastal environments, whose contribution to total Nr losses remains to be evaluated.

Criterios exigidos en revistas odontológicas venezolanas para la publicación de la fotografía extraoral en casos clínicos / Criteria required in Venezuelan dental journals for the publication of the extraoral photographs in case reports

Objetivo. Describir los criterios exigidos en revistas odontológicas venezolanas para la publicación de la fotografía clínica extraoral en los casos clínicos publicados en el periodo 2010-2021. Métodos. Investigación de enfoque cuantitativo, alcance descriptivo y transversal. Se analizaron artículos científicos que incluyeran fotografías clínicas extraorales publicadas en revistas odontológicas venezolanas entre 2010 y 2021. Resultados. Se observó exigencia por parte de la editorial en las estrategias de preservación de identidad del paciente, sumado al uso del consentimiento informado para las publicaciones de fotografías clínicas extraorales de casos clínicos. Conclusiones. La revista Acta Odontológica hace mayor uso de consentimiento informado, además de utilizar el enmascaramiento y anonimato como método de preservación de la identidad en sus publicaciones.

Objective. To describe the criteria required in Venezuelan dental journals for the publication of extraoral clinical photography in clinical cases published in the period 2010- 2021. Methods. Research with a quantitative approach, descriptive scope, and cross-sectional design. Scientific articles that included extraoral clinical photographs published in Venezuelan dental journals between 2010 and 2021 were analyzed. Results. There was a need from the publisher in the strategies of preservation of the patient's identity, and to the use of informed consent for the publication of photographs. extraoral clinics of clinical cases. Conclusions. The Acta Odontológica journal makes greater use of in- formed consent, in addition to using masking and anonymity as a method of identity preservation in its publications.

Electron shuttling mediated by humic substances fuels anaerobic methane oxidation and carbon burial in wetland sediments.

Key pathways for the anaerobic oxidation of methane (AOM) have remained elusive, particularly in organic rich ecosystems. In this work, the occurrence of AOM driven by humus-catalyzed dissimilatory iron reduction was investigated in sediments from a coastal mangrove swamp. Anoxic sediment incubations supplied with both goethite (α-FeOOH) and leonardite (humic substances (HS)) displayed an average AOM rate of 10.7 ±â€¯0.8 µmol CH4 cm-3 day-1, which was 7 and 3 times faster than that measured in incubations containing only goethite or HS, respectively. Additional incubations performed with 13C-methane displayed Pahokee Peat HS-mediated carbonate precipitation linked to 13CH4 oxidation and ferrihydrite reduction (~1.3 µmol carbonate cm-3 day-1). These results highlight the role of HS on mitigating greenhouse gases released from wetlands, not only by mediating the AOM process, but also by enhancing carbon sequestration as inert minerals (calcite, aragonite and siderite).

Eficacia de una intervención educativa en el nivel de conocimiento sobre prevención de cáncer de mama en mujeres del Asentamiento Humano Tiwinza û Puente Piedra / Educational Intervention Efficacy in the level of knowledge about Breast Cancer in Tiwinsa-Puente Piedra Shanty Town Woman 2012

Determinar la eficacia de una intervención educativa en el nivel de conocimiento de cáncer de mama en mujeres entre 30-65 años de edad del Asentamiento Humano Tiwinza de Puente Piedra en el año 2012. Diseño Metodológico: tipo de estudio de diseño pre-experimental de intervención a un solo grupo, prospectivo. Población y Muestra: La población del grupo etáreo de 30 a 65 años fue de 285 mujeres. La muestra fue probabilística y estuvo constituida por 61 mujeres que cumplieron los criterios de selección. La recolección de datos se realizó aplicando un cuestionario diseñado por las autoras, que fueron previamente validado por expertos de la especialidad y prueba piloto. Los resultados fueron analizados aplicando la æÆtÆÆ pareada. Resultados: el nivel de conocimiento antes de la intervención educativa fue deficiente en un 82%; seguido del nivel regular con un 16,4%. Sin embargo, después de la intervención educativa el nivel que predominó fue muy bueno con un 47,6%; seguido del regular con 13,1%. No se presentaron mujeres con nivel deficiente de conocimientos. Conclusiones: la intervención educativa fue eficaz al lograr aumentar de forma significativa el nivel de conocimientos de todas las variables analizadas...

Objetive: To determine the effectiveness of an educational intervention on the level of knowledge of breast cancer in women between 30-65 years of age created in Tiwinza, Puente Piedra in 2012. Methods: The research design was pre-experimental intervention to one group, prospective. The population at the age group of 30-65 years was 285 women. The sample consisted of probabilistic and 61 women who met the inclusion criteria. Data collection was conducted using a questionnaire designed by the authors, who were previously validated by experts in the field and pilot. The results were analyzed using the paired ôtÆÆ. Results: The level of knowledge before the educational intervention was so poor with 82%; followed by the regular level with a 16, 4%. However, after the educational intervention the level that prevailed was very good with 47,6%, followed by a 13,1% regular level. These were no women with poor level of knowledge of breast cancer. Conclusions: The educational intervention was effective in achieving significantly increase the level of knowledge of all the variables analyzed...