Design of a Portable Analyzer to Determine the Net Exchange of CO2 in Rice Field Ecosystems.

Global warming is influenced by an increase in greenhouse gas (GHG) concentration in the atmosphere. Consequently, Net Ecosystem Exchange (NEE) is the main factor that influences the exchange of carbon (C) between the atmosphere and the soil. As a result, agricultural ecosystems are a potential carbon dioxide (CO2) sink, particularly rice paddies (Oryza sativa). Therefore, a static chamber with a portable CO2 analyzer was designed and implemented for three rice plots to monitor CO2 emissions. Furthermore, a weather station was installed to record meteorological variables. The vegetative, reproductive, and maturation phases of the crop lasted 95, 35, and 42 days post-sowing (DPS), respectively. In total, the crop lasted 172 DPS. Diurnal NEE had the highest CO2 absorption capacity at 10:00 a.m. for the tillering stage (82 and 89 DPS), floral primordium (102 DPS), panicle initiation (111 DPS), and flowering (126 DPS). On the other hand, the maximum CO2 emission at 82, 111, and 126 DPS occurred at 6:00 p.m. At 89 and 102 DPS, it occurred at 4:00 and 6:00 a.m., respectively. NEE in the vegetative stage was -25 µmolCO2 m2 s-1, and in the reproductive stage, it was -35 µmolCO2 m2 s-1, indicating the highest absorption capacity of the plots. The seasonal dynamics of NEE were mainly controlled by the air temperature inside the chamber (Tc) (R = -0.69), the relative humidity inside the chamber (RHc) (R = -0.66), and net radiation (Rn) (R = -0.75). These results are similar to previous studies obtained via chromatographic analysis and eddy covariance (EC), which suggests that the portable analyzer could be an alternative for CO2 monitoring.

Necesidad de regeneración ósea en la instalación de implantes: Análisis Retrospectivo de 7 años, Hospital San Camilo

Objetivo: Analizar la necesidad de regeneración ósea guiada en pacientes sometidos a terapia implantológica entre el año 2012 y 2019 del Hospital San Camilo, San Felipe. Material y Método: Estudio observacional retrospectivo. Se incluyeron todos los pacientes pertenecientes al programa de implantes entre el 2012 y 2019. Los pacientes fueron organizados de acuerdo a la edad, género, marca de implante, uso de injerto, tiempo de carga y tasa de pérdida. Estos datos se evaluaron empleando estadística descriptiva calculando frecuencias y porcentajes en tablas de contingencias. Resultados: Se incluyeron 182 pacientes. La distribución por sexo fue de 121 mujeres y 61 hombres. La edad promedio de los pacientes fue de 51,23 años. El 41,76% casos del total requirió ROG. El 74,3% del grupo de implantes unitarios requirió injerto óseo. Sólo un 4,71% del grupo de sobredentadura requirió de injerto óseo. El tiempo de carga promedio fue de 3,68 meses. La tasa de pérdida en implantes fue de 3,85%. Conclusiones: El conocimiento y análisis de estos datos permite replantear la distribución de los recursos con el fin de realizar tratamientos más predecibles, disminuyendo las complicaciones y generando un ahorro de presupuesto.

Objective: To determine and analyze the need for guided bone regeneration (GBR) in patients who underwent implant therapy between 2012 and 2019 at the San Camilo Hospital, San Felipe. Material and methods: Retrospective observational study. All patients belonging to the implant program were included, with the need for either single implants or overdentures, which were installed between 2012 and 2019. Patients were organized according to their age, gender, implant brand, use of graft, loading time and loss rate. These data were evaluated using descriptive statistics calculating frequencies and percentages in contingency tables. Results: A total of 182 cases of implants were included. The distribution by sex was 121 women and 61 men. The average age of the patients was 51,23 years. The percentage of cases that required GBR was 41.76%. In the single implant group, 74.3% of cases required bone grafting. In the overdenture group, only 4.71% required bone grafting. The average loading time was 3,68 months. The implant loss rate was 3,85%. Conclusions: The knowledge and analysis of these data allow us to evaluate the distribution of resources to carry out more predictable treatments to reduce complications and generate budget savings.

Afrontamiento a la muerte en estudiantes de medicina del Paraguay en agosto 2021: estudio multicéntrico / Coping with death in Paraguayan medical students in August 2021: a multicenter study

RESUMEN Introducción: el afrontamiento a la muerte constituye una de las situaciones más difíciles y estresantes a las que se tienen que enfrentar los estudiantes de medicina por el contacto cercano a pacientes en riesgo vital. Objetivos: determinar el nivel de afrontamiento a la muerte en estudiantes de medicina. Metodología: se aplicó diseño con enfoque cuantitativo, de tipo observacional, transversal, multicéntrico. Se incluyó a estudiantes de medicina del Paraguay, de ambos sexos, en agosto 2021, que aceptaban participar del estudio. Se utilizó un cuestionario telemático. Se midieron variables sociodemográficas. El nivel de afrontamiento se determinó con la escala de Bugen. La investigación fue aprobada por Comité de Ética de la Universidad Privada del Este, Asunción. Resultados: se incluyeron 504 estudiantes, siendo del sexo femenino en 74 % y con edad media 22 ± 4 años. El 88 % de los encuestados eran de nacionalidad paraguaya (88 %) y 73 % de religión católica. La mayoría nació en Paraguay (88 %), era católica (73 %), se hallaba inscripta como donante de órganos (60 %) y tenía antecedente reciente de muerte de un familiar o amigo (76 %). La escala de Bugen detectó bajo nivel de afrontamiento a la muerte en 50 %, siendo 52 % en las mujeres y 42 % en los varones (p <0,05). Conclusión: el afrontamiento a la muerte en estudiantes de medicina fue bajo. Se sugiere incluir cursos, talleres y planes formativos dentro de las asignaturas o como actividades de extensión para mejorar ese aspecto en el currículo de las facultades de medicina del Paraguay.

ABSTRACT Introduction: coping with death is one of the most difficult tasks that medical students have to face. Objectives: to determine the level of coping with death in medical students. Methodology: we conducted an observational, cross-sectional, multicenter study. We included men and women, medical students from public and private universities from Paraguay in 2021, who agreed to participate in the study. A telematic questionnaire was used. Sociodemographic variables were measured. The level of coping was determined with the Bugen scale. The research was approved by the Comité de Ética of the Universidad Privada del Este, Asunción. Results: 504 students were included, 74 % being female and with a mean age of 22 ± 4 years. Most were born in Paraguay (88 %), were Catholic (73 %), registered as an organ donor (60 %), and had a recent history of the death of a family member or friend (76 %). The Bugen scale detected a low level of coping with death in 52 % of the women and 42 % of the men (p <0.05). Conclusion: coping with death in medical students was low. It is suggested to include courses or workshops to improve this aspect in the curriculum of the medical schools of Paraguay.

Diversity of microbial communities and genes involved in nitrous oxide emissions in Antarctic soils impacted by marine animals as revealed by metagenomics and 100 metagenome-assembled genomes.

Antarctic soils generally have low temperatures and limited availability of liquid water and nutrients. However, animals can increase the nutrient availability of ice-free areas by transferring nutrients from marine to terrestrial ecosystems, mainly through their excreta. In this study, we employed shotgun metagenomics and population genome binning techniques to study the diversity of microbial communities in Antarctic soils impacted by marine pinnipeds and birds relative to soils with no evident animal presence. We obtained ~285,000 16S rRNA gene-carrying metagenomic reads representing ~60 phyla and 100 metagenome-assembled genomes (MAGs) representing eight phyla. Only nine of these 100 MAGs represented previously described species, revealing that these soils harbor extensive novel diversity. Proteobacteria, Actinobacteria, and Bacteroidetes were the most abundant phyla in all samples, with Rhodanobacter being one of the most abundant genera in the bird-impacted soils. Further, the relative abundance of genes related to denitrification was at least double in soils impacted by birds than soils without animal influence. These results advance our understanding of the microbial populations and their genes involved in nitrous oxide emissions in ice-free coastal Antarctic soils impacted by marine animals and reveal novel microbial diversity associated with these ecosystems.

Seabird and pinniped shape soil bacterial communities of their settlements in Cape Shirreff, Antarctica.

Seabirds and pinnipeds play an important role in biogeochemical cycling by transferring nutrients from aquatic to terrestrial environments. Indeed, soils rich in animal depositions have generally high organic carbon, nitrogen and phosphorus contents. Several studies have assessed bacterial diversity in Antarctic soils influenced by marine animals; however most have been conducted in areas with significant human impact. Thus, we chose Cape Shirreff, Livingston Island, an Antarctic Specially Protected Area designated mainly to protect the diversity of marine vertebrate fauna, and selected sampling sites with different types of animals coexisting in a relatively small space, and where human presence and impact are negligible. Using 16S rRNA gene analyses through massive sequencing, we assessed the influence of animal concentrations, via their modification of edaphic characteristics, on soil bacterial diversity and composition. The nutrient composition of soils impacted by Antarctic fur seals and kelp gulls was more similar to that of control soils (i.e. soils without visible presence of plants or animals), which may be due to the more active behaviour of these marine animals compared to other species. Conversely, the soils from concentrations of southern elephant seals and penguins showed greater differences in soil nutrients compared to the control. In agreement with this, the bacterial communities of the soils associated with these animals were most different from those of the control soils, with the soils of penguin colonies also possessing the lowest bacterial diversity. However, all the soils influenced by the presence of marine animals were dominated by bacteria belonging to Gammaproteobacteria, particularly those of the genus Rhodanobacter. Therefore, we conclude that the modification of soil nutrient composition by marine vertebrates promotes specific groups of bacteria, which could play an important role in the recycling of nutrients in terrestrial Antarctic ecosystems.

Dataset of copper pipes corrosion after exposure to chlorine.

This article presents data on corrosion and dissolved copper in copper tubes that transport drinking water in domiciles of the Azogues city, Ecuador. Corrosion tests were performed using copper coupons exposed to water with different concentrations of free chlorine for 30, 60, 90 and 180 days. The determination of the copper corrosion rate exposed in chlorine was carried out by means of gravimetric tests. With weight loss data, the corrosion rate was determined. By means of static immersion tests, copper release of coupon surface was determined. In the obtained data it was observed that the corrosion rate and the release of copper increases with the chlorine concentration. This data is beneficial for drinking water companies and building builders by providing information on the corrosion and leaching behavior of copper pipes when exposed to chlorine and is useful for predicting the service life copper pipes. In addition, it could allow assessing the health risk by consuming water with copper in solution.

Evaluation of water quality and stability in the drinking water distribution network in the Azogues city, Ecuador.

This document presents the physical-chemical parameters with the objective of evaluating and analyzing the drinking water quality in the Azogues city applying the water quality index (WQI) and to research the water stability in the distribution network using corrosion indexes. Thirty samples were collected monthly for six months throughout the drinking water distribution network; turbidity, temperature, electric conductivity, pH, total dissolved solids, total hardness, calcium, magnesium, alkalinity, chlorides, nitrates, sulfates and phosphates were determined; the physical-chemical parameters were measured using standard methods. The processed data revealed that the average values ​​of LSI, RSI and PSI were 0.5 (±0.34), 6.76 (±0.6), 6.50 (±0.99) respectively. The WQI calculation indicated that 100% of the samples are considered excellent quality water. According to the Langelier, Ryznar and Pukorius indexes showed that drinking water in Azogues is corrosive. The quality of drinking water according to the WQI is in a good and excellent category.

Phylogenetic Diversity of Peltigera Cyanolichens and Their Photobionts in Southern Chile and Antarctica.

The lichen genus Peltigera has been mainly revised in the Northern Hemisphere, with most species being recorded in Europe and North America. This study assessed the phylogenetic diversity of the mycobionts and cyanobionts of Peltigera cyanolichens collected in Southern Chile and Antarctica, areas in which lichens are extremely diverse but poorly studied. The operational taxonomic units (OTUs) of each symbiont were defined by analyzing the genetic diversity of the LSU and SSU rDNA of the mycobionts and cyanobionts, respectively, and a phylogenetic approach was used to relate these OTUs with sequences previously reported for Peltigera and Nostoc. Among the 186 samples collected, 8 Peltigera and 15 Nostoc OTUs were recognized, corresponding to sections Peltigera, Horizontales, and Polydactylon, in the case of the mycobionts, and to the Nostoc clade II, in the case of the cyanobionts. Since some of the OTUs recognized in this study had not previously been described in these areas, our results suggest that the diversity of Peltigera reported to date in the regions studied using traditional morphological surveys has underestimated the true diversity present; therefore, further explorations of these areas are recommended.

Environmental context shapes the bacterial community structure associated to Peltigera cyanolichens growing in Tierra del Fuego, Chile.

The structure of the associated bacterial community of bipartite cyanolichens of the genus Peltigera from three different environmental contexts in the Karukinka Natural Park, Tierra del Fuego, Chile, was assessed. The sampling sites represent different habitat contexts: mature native forest, young native forest and grassland. Recently it has been determined that the bacterial community associated to lichens could be highly structured according to the mycobiont or photobiont identities, to the environmental context and/or to the geographic scale. However, there are some inconsistencies in defining which of these factors would be the most significant on determining the structure of the microbial communities associated with lichens, mainly because most studies compare the bacterial communities between different lichen species and/or with different photobiont types (algae vs. cyanobacteria). In this work bipartite lichens belonging to the same genus (Peltigera) symbiotically associated with cyanobacteria (Nostoc) were analyzed by TRFLP to determine the structure of the bacterial community intimately associated with the lichen thalli and the one present in the substrate where they grow. The results indicate that the bacterial community intimately associated differs from the one of the substrate, being the former more influenced by the environmental context where the lichen grows.

Genetic diversity of terricolous Peltigera cyanolichen communities in different conservation states of native forest from southern Chile

Decreasing quality of forest habitats is among the major factors leading to a loss of epiphytic lichen diversity. However, there is little information about how this factor influences the diversity of terricolous lichens, which do not grow over living trees and could be less susceptible to such disturbances. In this work we describe the genetic diversity of Peltigeraterricolous cyanolichens and their cyanobiont (Nostoc) from three habitats at the Karukinka Natural Park (Tierra del Fuego, southern Chile), which represent different conservation states: native mature-forest (low disturbance intensity), native young forest (medium disturbance intensity) and grassland (high disturbance intensity). In both forest contexts, a higher diversity and a higher number of unique OTUs (operational taxonomic units) were found. In contrast, in the grassland, the diversity was lower and the Peltigera species were mostly cosmopolitan. The presence of unique OTUs and the higher diversity of lichens in native forest areas highlight the importance of their preservation, indicating that decreasing forest quality also has a negative impact on terricolous lichens diversity (AU)

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Genetic diversity of terricolous Peltigera cyanolichen communities in different conservation states of native forest from southern Chile.

Decreasing quality of forest habitats is among the major factors leading to a loss of epiphytic lichen diversity. However, there is little information about how this factor influences the diversity of terricolous lichens, which do not grow over living trees and could be less susceptible to such disturbances. In this work we describe the genetic diversity of Peltigera terricolous cyanolichens and their cyanobiont (Nostoc) from three habitats at the Karukinka Natural Park (Tierra del Fuego, southern Chile), which represent different conservation states: native mature-forest (low disturbance intensity), native young-forest (medium disturbance intensity) and grassland (high disturbance intensity). In both forest contexts, a higher diversity and a higher number of unique OTUs (operational taxonomic units) were found. In contrast, in the grassland, the diversity was lower and the Peltigera species were mostly cosmopolitan. The presence of unique OTUs and the higher diversity of lichens in native forest areas highlight the importance of their preservation, indicating that decreasing forest quality also has a negative impact on terricolous lichens diversity.

Reinfarto de miocardio: análisis clínico-electrocardiográfico y detección por CK-MB / Myocardial re-infarction: clinic and electrocardiographic analysis and detection by CK-MB

En este estudio se analiza desde un punto de vista clínico, enzimático (dosaje seriado de CK-MB) y electrocardiográfico, la incidencia de reinfarto en la fase aguda de la evolución de 26 pacientes internados en la Unidad Coronaria, por haber padecido un infarto de miocardio transmural anterior. Mientras que ningún paciente presentó síntomas de re-infarto, 7 (26,9%) pacientes mostraron un nuevo incremento en los valores de CK-MB y 23 (88,46%) pacientes, signos electrocardiográficos de extensión del área necrótica. Estos resultados sugieren que durante el infarto, frecuentemente se registran cambios electrocardiográficos que simulan re-infarto, debido a alteraciones en la actividad eléctrica del corazón, no dependientes de la aparición de nuevas zonas de necrosis (AU)

Reinfarto de miocardio: análisis clínico-electrocardiográfico y detección por CK-MB / Myocardial re-infarction: clinic and electrocardiographic analysis and detection by CK-MB

En este estudio se analiza desde un punto de vista clínico, enzimático (dosaje seriado de CK-MB) y electrocardiográfico, la incidencia de reinfarto en la fase aguda de la evolución de 26 pacientes internados en la Unidad Coronaria, por haber padecido un infarto de miocardio transmural anterior. Mientras que ningún paciente presentó síntomas de re-infarto, 7 (26,9%) pacientes mostraron un nuevo incremento en los valores de CK-MB y 23 (88,46%) pacientes, signos electrocardiográficos de extensión del área necrótica. Estos resultados sugieren que durante el infarto, frecuentemente se registran cambios electrocardiográficos que simulan re-infarto, debido a alteraciones en la actividad eléctrica del corazón, no dependientes de la aparición de nuevas zonas de necrosis

Importancia de la curva horaria de CK/CK-MB en el infarto de miocardio / Importance of the time curve of CK/CK-MB in myocardial infarction

Numerosas investigaciones han demostrado la importancia de la determinación de Creatinkinasa (CK) EC 2.7.3.2 y su isoenzima CK-MB (tipo miocardio) en la "detección","cuantificación" y "pronóstico" del infarto agudo de miocardio (IAM). El objeto de este estudio es demostrar la importancia de los intervalos en toma de muestra para las determinaciones de actividad enzimática y poder establecer una real evaluación del máximo de actividad (valor máximo plasmático) de CK/CK-MB, según el horario de admisión del paciente después del inicio del IAM (temprano, intermedio, tardío) (AU)

Importancia de la curva horaria de CK/CK-MB en el infarto de miocardio / Importance of the time curve of CK/CK-MB in myocardial infarction

Numerosas investigaciones han demostrado la importancia de la determinación de Creatinkinasa (CK) EC 2.7.3.2 y su isoenzima CK-MB (tipo miocardio) en la "detección","cuantificación" y "pronóstico" del infarto agudo de miocardio (IAM). El objeto de este estudio es demostrar la importancia de los intervalos en toma de muestra para las determinaciones de actividad enzimática y poder establecer una real evaluación del máximo de actividad (valor máximo plasmático) de CK/CK-MB, según el horario de admisión del paciente después del inicio del IAM (temprano, intermedio, tardío)