14 research outputs found

    Exploring the presence of five rare earth elements in vineyard soils on different lithologies: Campo de Calatrava, Spain

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    The aim of the work described here was to understand the pedogeochemical signature of five rare earth elements (REEs; Ce, Nd, La, Y, and Sc) in vineyard soils in Campo de Calatrava (a unique territory with calcareous, volcanic and metamorphic rocks). The mean contents in surface horizons of Ce, Nd, La, Y, and Sc were 65.7, 32.0, 35.5, 18.8, and 13.9 mg·kg–1, respectively. In subsurface horizons the contents were Ce 62.8, Nd 31.1, La 35.7, Y 17.9, and Sc 14.4 mg·kg–1 . The results show that mean contents of REEs in the area under investigation are in the order Ce > Nd > La > Y > Sc. Ce has a very high range, with a value close to 150 mg·kg–1 . On the other hand, concentrations of Ce, Nd, Y, and Sc are higher in soils on volcanic material than in soils on nonvolcanic material, while only La values are lower in soils on volcanic rocks. The distributional maps of REEs in surface and subsurface horizons suggest that parent material and pedogenesis such as argillization and calcium carbonate accumulation are more important factors than the use of REE-based fertilizers, except in certain exceptional cases (consistent with a possible specific human impact after continuous fertilization

    The relationship between terpenes and flammability of leaf litter

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    Many studies have assumed that plant terpenes favor fire due to their enormous flammability. However, only a few of them, all performed on green leaves, have demonstrated this. In the present work we investigated the question of whether litter terpene content can be used to estimate flammability and temperatures reached during fire. Epiradiator and burn table tests were used to compare flammability of leaf litter of P. pinaster, P. halepensis, P. pinea, C. albidus, C. ladanifer, C. laurifolius and the mixture of litter of P. pinaster with that of the other five species (e.g. P. pinaster + P. halepensis). Tests with burn table showed increasing spread rates and shorter combustion times under higher terpene contents. Flame height was triggered both with higher a terpene content and bed thickness, whereas the percentage of burned biomass was only significantly correlated to bed height. Epiradiator tests indicated that terpene concentration in leaf litter was positively correlated to flame height and negatively correlated to both flame residence time and ignition delay. Flammability was high for P. pinaster, P. halepensis, and hence for P. pinaster + P. halepensis, intermediate for C. albidus, P. pinea and P. pinaster combined with each of these species, and low for C. laurifolius, C. ladanifer and P. pinaster combined with them. Accordingly, their terpene content was high, intermediate and low. We concluded that plants might influence fire intensity, by having stored terpenes in their dead leaves, in addition to having developed traits to survive fire. Thus, a correct management of dead aboveground fuels rich in terpene concentrations, such as those of P. pinaster and P. halepensis, could prove helpful in reducing the hazard of fire

    Characteristics of undergraduate dental theses defended in Peruvian licensed universities and factors associated with their publication

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    IntroductionIn Peru, the defense of a university thesis allow to obtain a professional degree and demonstrate the research skills of the aspirant.ObjectivesTo characterize the undergraduate dental theses defended in Peruvian universities and those published in scientific journals, as well as to identify the factors associated with their publication.MethodsA cross-sectional, analytical and observational study was conducted using a search strategy in Google Scholar. We ascertained whether the theses defended between 2015-2018 had been published in scientific journals. Prevalence ratios (aPR), 95% confidence intervals (CI 95%) and p-values were obtained using generalized linear models.ResultsMost of the theses were defended in private universities (65.9%), located in the provinces (76.7%), in 2017 (32.1%). The most studied line of research was Dental Education (n = 418; 18.4%). Of the total number of defended theses (n = 2,267), only 130 (5.7%) were published, in a total of 41 scientific journals, of which 22 are specialized in the dental field. The 130 articles received 443 citations, with an average of 3.4 citations per document. The Universidad Católica Santa María was the institution that defended the most theses (n = 372); however, the Universidad Científica del Sur presented the highest percentage of published theses (36.4%). Theses with case-control (aPR: 2.74; CI 95%: 1.07-7.01; p = 0.036) and cohort (aPR: 3.51; CI 95%: 2.02-6.11; p  < 0.001) methodological design had a higher frequency of publication; on the contrary, those executed in the community were less frequently published (aPR: 0.39; CI 95%: 0.17-0.93; p = 0.033), as well as, those with two researchers (aPR: 0.41; CI 95%: 0.18-0.92; p = 0.031), adjusted for two variables.ConclusionOnly one in twenty theses was published. Publication was associated with the type of methodological design, the place of execution and the number of researchers

    Enterococcus faecalis: pathogen of relevance in endodontic treatment failures

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    Enterococcus faecalis is a microorganism related to different disease including endodontic infections. Due to its presence in the root canals after completing an endodontic treatment, its is related to the faulures of these tratments. This bacterium has variety of virulence factors such as hemolysin, gelatinase and its ability to resist multiple antimicrobials make it an extremely aggressive microorganism. It is a pathogen present in bacteremia and systemic disease. This review will allow to know a litle more about this micoorganism trying to focus on the infectious processes of the root canals. 

    Genome-wide identification of the Phaseolus vulgaris sRNAome using small RNA and degradome sequencing

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    Background: MiRNAs and phasiRNAs are negative regulators of gene expression. These small RNAs have been extensively studied in plant model species but only 10 mature microRNAs are present in miRBase version 21, the most used miRNA database, and no phasiRNAs have been identified for the model legume Phaseolus vulgaris. Thanks to the recent availability of the first version of the common bean genome, degradome data and small RNA libraries, we are able to present here a catalog of the microRNAs and phasiRNAs for this organism and, particularly, we suggest new protagonists in the symbiotic nodulation events.Results: We identified a set of 185 mature miRNAs, including 121 previously unpublished sequences, encoded by 307 precursors and distributed in 98 families. Degradome data allowed us to identify a total of 181 targets for these miRNAs. We reveal two regulatory networks involving conserved miRNAs: those known to play crucial roles in the establishment of nodules, and novel miRNAs present only in common bean, suggesting a specific role for these sequences. In addition, we identified 125 loci that potentially produce phased small RNAs, with 47 of them having all the characteristics of being triggered by a total of 31 miRNAs, including 14 new miRNAs identified in this study.Conclusions: We provide here a set of new small RNAs that contribute to the broader knowledge of the sRNAome of Phaseolus vulgaris. Thanks to the identification of the miRNA targets from degradome analysis and the construction of regulatory networks between the mature microRNAs, we present here the probable functional regulation associated with the sRNAome and, particularly, in N2-fixing symbiotic nodules.Peer reviewedBiochemistry and Molecular Biolog

    Mortality from gastrointestinal congenital anomalies at 264 hospitals in 74 low-income, middle-income, and high-income countries: a multicentre, international, prospective cohort study

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    Summary Background Congenital anomalies are the fifth leading cause of mortality in children younger than 5 years globally. Many gastrointestinal congenital anomalies are fatal without timely access to neonatal surgical care, but few studies have been done on these conditions in low-income and middle-income countries (LMICs). We compared outcomes of the seven most common gastrointestinal congenital anomalies in low-income, middle-income, and high-income countries globally, and identified factors associated with mortality. Methods We did a multicentre, international prospective cohort study of patients younger than 16 years, presenting to hospital for the first time with oesophageal atresia, congenital diaphragmatic hernia, intestinal atresia, gastroschisis, exomphalos, anorectal malformation, and Hirschsprung’s disease. Recruitment was of consecutive patients for a minimum of 1 month between October, 2018, and April, 2019. We collected data on patient demographics, clinical status, interventions, and outcomes using the REDCap platform. Patients were followed up for 30 days after primary intervention, or 30 days after admission if they did not receive an intervention. The primary outcome was all-cause, in-hospital mortality for all conditions combined and each condition individually, stratified by country income status. We did a complete case analysis. Findings We included 3849 patients with 3975 study conditions (560 with oesophageal atresia, 448 with congenital diaphragmatic hernia, 681 with intestinal atresia, 453 with gastroschisis, 325 with exomphalos, 991 with anorectal malformation, and 517 with Hirschsprung’s disease) from 264 hospitals (89 in high-income countries, 166 in middleincome countries, and nine in low-income countries) in 74 countries. Of the 3849 patients, 2231 (58·0%) were male. Median gestational age at birth was 38 weeks (IQR 36–39) and median bodyweight at presentation was 2·8 kg (2·3–3·3). Mortality among all patients was 37 (39·8%) of 93 in low-income countries, 583 (20·4%) of 2860 in middle-income countries, and 50 (5·6%) of 896 in high-income countries (p<0·0001 between all country income groups). Gastroschisis had the greatest difference in mortality between country income strata (nine [90·0%] of ten in lowincome countries, 97 [31·9%] of 304 in middle-income countries, and two [1·4%] of 139 in high-income countries; p≤0·0001 between all country income groups). Factors significantly associated with higher mortality for all patients combined included country income status (low-income vs high-income countries, risk ratio 2·78 [95% CI 1·88–4·11], p<0·0001; middle-income vs high-income countries, 2·11 [1·59–2·79], p<0·0001), sepsis at presentation (1·20 [1·04–1·40], p=0·016), higher American Society of Anesthesiologists (ASA) score at primary intervention (ASA 4–5 vs ASA 1–2, 1·82 [1·40–2·35], p<0·0001; ASA 3 vs ASA 1–2, 1·58, [1·30–1·92], p<0·0001]), surgical safety checklist not used (1·39 [1·02–1·90], p=0·035), and ventilation or parenteral nutrition unavailable when needed (ventilation 1·96, [1·41–2·71], p=0·0001; parenteral nutrition 1·35, [1·05–1·74], p=0·018). Administration of parenteral nutrition (0·61, [0·47–0·79], p=0·0002) and use of a peripherally inserted central catheter (0·65 [0·50–0·86], p=0·0024) or percutaneous central line (0·69 [0·48–1·00], p=0·049) were associated with lower mortality. Interpretation Unacceptable differences in mortality exist for gastrointestinal congenital anomalies between lowincome, middle-income, and high-income countries. Improving access to quality neonatal surgical care in LMICs will be vital to achieve Sustainable Development Goal 3.2 of ending preventable deaths in neonates and children younger than 5 years by 2030

    Estroncio (Sr) acumulado en hojas de villa (Vitis vinifera L.) en Castilla- La Mancha.

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    Castilla-La Mancha es una de las regiones viticolas mas importantes y extensas del mundo. La creciente preocupacien de los mercados por la calidad y la autenticidad del vino, hace que cada vez tenga mas importancia el concepto \\\\terroir\\\\ para poner en valor los productos vitivinicolas. Estudiar la composición geoquímica de los suelos, junto con otras propiedades del mismo (como el pH, conductividad eléctrica, contenido en carbonato cálcico, etc.), puede indicar los diferentes elementos químicos presentes en el suelo en el que se cultiva In vid y su disponibilidad para la planta. Una de los elementos traza que se encuentra en mayor concentración en los suelos vitícolas es el estroncio (Sr). El Sr, por su abundancia relativa y su similitud metabólica con el calcio, se acumula en las paredes vegetales de forma estable y puede ser un buen indicador del origen del suelo en el que se ha cultivado la vid. La capacidad de la planta para absorber elementos químicos se puede estimar con el coeficiente de bioacumulación, calculado como el cociente entre la concentración del elemento en in planta y su concentración en el suelo. El objetivo de este trabajo es estudiar la absorción del estroncio y su acumulación en hoja de vid. Para ello se han estudiado los contenidos de estroncio de 101 muestras de suelos vitícolas y hoja de vid procedentes de distintos puntos de Castilla-La Mancha, mediante fluorescencia de rayos X. Se ha calculado el coeficiente de bioacumulación de estroncio diferenciando entre ordenes de suelo (clasificados según USDA, a excepción de los calcisoles, clasificados siguiendo el criterio FAO) y valores de pH. Las correlaciones lineales entre la cantidad de Sr en suelo-hoja encontradas nos permiten establecer diferencias entre los distintos suelos analizados. Asi, se han obtenido correlaciones positivas y significativas para alfisoles (R=0,83), entisoles (R=0,83) e inceptisoles (R=0,96). Sin embargo, sorprendentemente, no se ha encontrado correlación significativa en calcisoles debido a la presencia de horizonte petrocálcico

    Zonificación de suelos vitícolas en Villanueva de Alcardete (Toledo, La Mancha, España) utilizando elementos traza.

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    Se realiza un estudio de suelos en el término municipal de Villanueva de Alcardete (Toledo, España) con la finalidad de señalar zonas homogéneas para el cultivo del viñedo. Se practicaron 15 calicatas en lugares representativos y se realizaron análisis físico químicos y clasificaciones edafológicas. También se consultaron fuentes clásicas de información pero se apunta como novedosa herramienta para la zonificación la composición geoquímica de los suelos. Se determinaron para cada perfil 11 elementos mayoritarios (Al, Ca, Fe, K, Na, Mg, Mn, P, S, Si, Ti) y 27 elementos traza (As, Ba, Ce, Co, Cr, Cs, Cu, Ga, Hf, La, Mo, Nb, Nd, Ni, Pb, Rb, Sc, Sn, Sr, Ta, Th, U, V, W, Y, Zn, Zr). Una vez estudiadas las fuentes de información y los datos obtenidos, el mapa de distribución del Estroncio (Sr) representa bastante bien las distintas zonas de suelos del área estudiada y puede ser utilizado (con las debidas comprobaciones y correcciones) para establecer lotes de suelos homogéneos

    Estudio de las propiedades de retención de humedad de suelos vitícolas en Castilla-La Mancha (España)

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    En el presente trabajo se estudió la relación entre las principales características del suelo que influyen en la retención de humedad (densidad aparente y porcentajes de arena, limo, arcilla, materia orgánica y carbonato cálcico) y la humedad gravimétrica a capacidad de campo (CC), punto de marchitez permanente (PMP) y capacidad de retención de agua disponible (CRAD) o agua útil de los horizontes superficiales de 101 suelos vitícolas de Castilla-La Mancha (España). Los suelos se describieron morfológicamente y se realizaron los análisis pertinentes de establecimiento de las principales propiedades de los mismos. La CC y PMP se determinaron con el método de placas Richards (aplicando -33 KPa y -1500 KPa, respectivamente) y la CRAD fue deducida por diferencia (CC-PMP). Del Análisis de Componentes Principales se deduce que dos componentes explican el 61,76% de la variabilidad de los datos (porcentaje de contenido en arena y densidad aparente). Las propiedades que mostraron una mayor relación lineal, estadísticamente significativa, con CC, PMP y CRAD fueron el porcentaje de arena (R= -0,68, -0,68 y -0,47) y de limo (0,5, 0,49 y 0,37) respectivamente. Se utilizóel programa Surfer para la elaboración de mapas de distribución espacial de propiedades del suelo

    Estudio de las propiedades de retención de humedad de suelos vitícolas en Castilla-La Mancha (España)

    No full text
    En el presente trabajo se estudió la relación entre las principales características del suelo que influyen en la retención de humedad (densidad aparente y porcentajes de arena, limo, arcilla, materia orgánica y carbonato cálcico) y la humedad gravimétrica a capacidad de campo (CC), punto de marchitez permanente (PMP) y capacidad de retención de agua disponible (CRAD) o agua útil de los horizontes superficiales de 101 suelos vitícolas de Castilla-La Mancha (España). Los suelos se describieron morfológicamente y se realizaron los análisis pertinentes de establecimiento de las principales propiedades de los mismos. La CC y PMP se determinaron con el método de placas Richards (aplicando -33 KPa y -1500 KPa, respectivamente) y la CRAD fue deducida por diferencia (CC-PMP). Del Análisis de Componentes Principales se deduce que dos componentes explican el 61,76% de la variabilidad de los datos (porcentaje de contenido en arena y densidad aparente). Las propiedades que mostraron una mayor relación lineal, estadísticamente significativa, con CC, PMP y CRAD fueron el porcentaje de arena (R= -0,68, -0,68 y -0,47) y de limo (0,5, 0,49 y 0,37) respectivamente. Se utilizóel programa Surfer para la elaboración de mapas de distribución espacial de propiedades del suelo
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