2,007 research outputs found
Proyecto Editorial: Diseño de Revista "Cultura Lilith"
Universidad de Sevilla. Grado en Publicidad y Relaciones Pública
Sistema de clasificación para humedales interiores sobre arenas cuarcíticas en Pinar del Río, Cuba
Pinar del Río, the Cuba western province, treasures in its southern plain extreme ecosystems characterized by the presence of quartzite sands, and over them the greatest diversity of freshwater wetlands in the country is distributed; nowadays there is no tool to define them, taking into account the marked water level variations during different seasons. For achieving the main goal in its classification regarding flood levels; a tape measure was used to determine the waterdepth above surface in dry and rainy season, as well as the distance from the natural capacity to the lagoon center. Besides, piezometers graduated in centimeters were permanently installed at the natural gauging point of the lagoon to measure the monthly variation of surface water level in each one of them. This issue offers a fresh water wetland classification system, based on four basic categories: shallow seasonal lagoon, shallow semi-seasonal lagoon, semi-seasonal lagoons with inside lagoons and permanent lagoons; this classification system shows flood levels influence on variability to the studied ecosystems.Pinar del Río, la provincia más occidental de Cuba, atesora en su llanura sur ecosistemas extremos caracterizados por la presencia de arenas cuarcíticas, sobre ellas se distribuye la mayor variedad de humedales interiores de agua dulce del país, y hasta la fecha no existe una herramienta para definirlos, teniendo encuenta las marcadas variaciones en la presencia de agua durante las diferentes estaciones del año. Con el objetivo de clasificar estos humedales interiores conrespecto a sus niveles de inundación; se utilizó una cinta métrica para determinar, la profundidad del agua por encima de la superficie en época de seca y lluvia, así como la distancia del aforo natural hasta el centro de la laguna; además se instalaron de manera permanente, piezómetros graduados en centímetros sobre el aforo natural de la laguna, para medir la variación mensual de la lámina de agua superficial, en cada una de las lagunas objeto de estudio. Como resultado del trabajo, se brinda un sistema de clasificación que comprende cuatro categorías básicas de humedales interiores: laguna estacional somera, laguna semiestacional poco profunda, lagunas semiestacional con lagunas interiores, y lagunas permanentes; esta clasificación demuestra como los niveles de inundación, influyen en la variabilidad de los ecosistemas estudiados
Macrobotanical evidence (wood charcoal and seeds) from the Middle Palaeolithic site of El Salt, Eastern Iberia: Palaeoenvironmental data and plant resources catchment areas
Despite the current growing number of studies that focus on macrobotanical remains from Middle Palaeolithic contexts, plant use among hunter-gatherer societies remains unknown in many regions of Europe. Large-scale flotation of archaeological sediments has made it possible to recover a large amount of plant remains (fruits, seeds and wood) from units VIII, IX, Xa and Xb at El Salt, Eastern Iberia (49.2-52.3 ka BP). The combination of anthracological and carpological analyses has provided a more accurate picture of the Middle Palaeolithic landscape in the Serpis valley, as well as significant information about other possible uses of plants, not only as fuel, but for woodworking or food, for instance. A minimum of twenty different taxa have been identified among the plant remains. Charcoal analysis suggested that firewood was gathered from nearby sources (< 1 km), with a predominance of black-scots pine woodlands (Pinus nigra-sylvestris) and maples (Acer sp.). The carpological data reveal the use of some woody taxa not documented in the anthracological record (Taxus baccata or yew) and the presence of few mineralised seeds whose origin remains unknown (Celtis australis or hackberry, Rubus cf. laciniatus or evergreen blackberry). These data have significant implications for the interpretation of plant economy among Neanderthal groups, reinforcing the importance of available woody resources in the surroundings for the subsistence of the group
Leaching of pure chalcocite in a chloride media using sea water and wastewater
Chalcocite is the most important and abundant secondary copper ore in the world with a rapid dissolution of copper in an acid-chloride environment. In this investigation, the methodology of surface optimization will be applied to evaluate the e_ect of three independent variables (time, concentration of sulfuric acid and chloride concentration) in the leaching of pure chalcocite to extract the copper with the objective of obtaining a quadratic model that allows us to predict the extraction of copper. The kinetics of copper dissolution in regard to the function of temperature is also analyzed. An ANOVA indicates that the linear variables with the greatest influence are time and the chloride concentration. Also, the concentration of chloride-time exerts a significant synergic e_ect in the quadratic model. The ANOVA indicates that the quadratic model is representative and the R2 value of 0.92 is valid. The highest copper extraction (67.75%) was obtained at 48 h leaching under conditions of 2 mol/L H2SO4 and 100 g/L chloride. The XRD analysis shows the formation of a stable and non-polluting residue; such as elemental sulfur (S0). This residue was obtained in a leaching time of 4 h at room temperature under conditions of 0.5 mol/L H2SO4 and 50 g/L Cl.The authors are grateful for the contribution of the Scientific Equipment Unit- MAINI of the Universidad Católica del Norte for aiding in generating data by automated electronic microscopy QEMSCAN® and for facilitating the chemical analysis of the solutions. We are also grateful to the Altonorte Mining Company for supporting this research and providing slag for this study, and we thank to Marina Vargas Aleuy and María Barraza Bustos of the Universidad Católica del Norte for supporting the experimental tests
Detection, size characterization and quantification of silver nanoparticles in consumer products by particle collision coulometry
Silver nanoparticles (AgNPs) are widely used in industrial and consumer products owing to its antimicrobial nature and multiple applications. Consequently, their release into the environment is becoming a big concern because of their negative impacts on living organisms. In this work, AgNPs were detected at a potential of + 0.70 V vs. Ag/AgCl reference electrode, characterized, and quantified in consumer products by particle collision coulometry (PCC). The electrochemical results were compared with those measured with electron microscopy and single-particle inductively coupled plasma mass spectrometry. The theoretical and practical peculiarities of the application of PCC technique in the characterization of AgNPs were studied. Reproducible size distributions of the AgNPs were measured in a range 10–100 nm diameters. A power allometric function model was found between the frequency of the AgNPs collisions onto the electrode surface and the number concentration of nanoparticles up to a silver concentration of 1010 L-1 (ca. 25 ng L-1 for 10 nm AgNPs). A linear relationship between the number of collisions and the number concentration of silver nanoparticles was observed up to 5 × 107 L-1. The PCC method was applied to the quantification and size determination of the AgNPs in three-silver containing consumer products (a natural antibiotic and two food supplements). The mean of the size distributions (of the order 10–20 nm diameters) agrees with those measured by electron microscopy. Graphical abstract: [Figure not available: see fulltext.]
Potential fields modeling for the Cayos Basin (Western Caribbean Plate): Implications in basin crustal structure
The Cayos Basin is an offshore basin located in the Colombian Caribbean Sea and forms part of the Lower Nicaraguan Rise, a geological province of the western region of the Caribbean Plate. Until now, the origin of the province is still being debated. Advanced research in the study area regarding its composition and structure, from land outcrops, petrology and geochemistry of drilled cores and dredged samples, and geophysical investigations, indicates a volcanic origin for this geological province, and a close relationship to the formation of the Caribbean Large Igneous Province. On the contrary, other studies suggest that the Lower Nicaraguan Rise may be part of the continental Chortis block. In this paper, we present and discuss alternative scenarios for the nature of the underlying crust below the sedimentary sequences in the Cayos Basin. We characterize the basin through the interpretation of magnetic and gravity anomaly grids, and 2D forward modeling, constructed based on three sections, by considering restriction seismic data from previous works. The results show that the Cayos Basin is underlain by geological bodies with high density and higher magnetization. From the gravity and magnetic forward modeling, we estimated the depth to the basement is about 2-6 km, and the Moho discontinuity to have an average of 18 km below, the Cayos Basin. Our investigation implies that, at least, the Cayos Basin is in the oceanic crust domain and shows no evidence of a continental source of the Chortis block
Detection of chromosomal translocations by cytogenetic diagnosis. Cienfuegos, 2006-2016
Background: Chromosomal abnormalities frequently cause pregnancy losses and infertility, and they are an important cause of mental retardation. Early diagnosis allows extending the study to the families of these translocations carriers.Objective: to identify chromosomal translocations by cytogenetic diagnosis.Methods: a retrospective description was conducted of the studied cases between 2006 and 2016 of fetuses diagnosed with some translocation, which were grouped in 10 families (25 individuals). Data were taken from the CPGMC records, which contain the prenatal chromosomal diagnoses of population at risk, and postnatal studies in peripheral blood performed to parents and other fetuses relatives. The following variables were analyzed: diagnosis (sick, healthy carrier), type of chromosomal aberration (structural, numerical), heritability pathway of structural anomalies (father or mother), chromosome formula and type of translocation.Results: out of all positive cases and carriers diagnosed prenatally, 76.71% were numerical anomalies. From 17 cases of structural anomalies, 13 were chromosomal translocations, (balanced and unbalanced), all inherited from one of the progenitors. Two sick individuals and 23 healthy carriers in the studied families were identified by prenatal and postnatal diagnosis.Conclusion: in the Cienfuegos province, there is a healthy group of people who carry chromosomal translocations, which can be transmited to their descendants; therefore with the possibility that they are born with malformations.</p
Development of support material for health professionals who are implementing Shared Decision-making in breast cancer screening: validation using the Delphi technique
Background The Literature is no report support material on Shared Decision-making applied to breast cancer screening that is intended for Spanish health professionals. The researcher created both a handbook and a guide for this topic using an adaption of the Three-talk model. Objective A Delphi method will be used to reach an agreement among experts on the contents and design of a manual and guide, designed by the research team, and to be used by health professionals in the application of SDM in breast cancer screening. Design A qualitative study. The content and design of the handbook and the guide was discussed by 20 experts. The Delphi techniques was in an online mode between July and October 2020 and researchers used Google forms in three rounds with open and closed questions. The criterion established for consensus was a coefficient of concordance (Cc) above 75, for questions using a Likert scale of 1-6-in which 1 meant 'completely disagree' and 6 'completely agree'-with a cut-off point equal to or higher than 4. Results Participants considered the Three-talk model suitable for the screening context. The handbook sections and level of detail were considered satisfactory (Cc=90). The summary provided by the clinical practice guide was considered necessary (Cc=75), as it was the self-assessment tool for professionals (Cc=85). Content was added: addressing the limitations of the SDM model; extending the number of sample dialogues for health professionals; providing supplementary resources on using Patient Decisions aids and adding references on communication skills. Conclusions and applications The first handbook and clinical practice guide providing unique SDM support material for health professionals have been developed. The handbook and guide are useful and innovative as supporting material for health professionals, but training strategies for SDM and a piloting plan for the use of materials are requested, in order to facilitate its implementation
LA AUSENCIA DE INFORMACIÓN EN LOS PROCESOS DE MANTENIMIENTO COMO PRINCIPAL FACTOR QUE IMPIDE LA TOMA DE DECISIONES EN LA EMPRESA SODINLEC EN LOS AÑOS 2018 Y 2019.
El proyecto desarrollado como proyecto de grado de la Especialización en Gestión de Proyectos denominado “LA AUSENCIA DE INFORMACIÓN EN LOS PROCESOS DE MANTENIMIENTO COMO PRINCIPAL FACTOR QUE IMPIDE LA TOMA DE DECISIONES EN LA EMPRESA SODINLEC EN LOS AÑOS 2018 Y 2019”.
El principal objetivo es analizar la importancia de la disponibilidad de la información en los procesos operativos de mantenimiento en redes eléctricas ofrecidos por la empresa Sodinlec Ltda, para la toma oportuna de decisiones que apoye y promueva el proceso de mejora continua de la compañía, identificando el impacto negativo que causa la ausencia de datos para la medición de la calidad y eficiencia en la realización de las actividades asociadas a los servicios prestados.This project development as degree of specialization in project management called “THE ABSENCE OF THE INFORMATION IN THE PROCESS OF MAINTENANCE WITH PRINCIPAL FACTOR WHAT DO NOT LEFT TO TAKE THE DECISIONS IN THE COMPANY SODINLEC BETWEN THE YEARS 2018 – 2019”.
The principal objective is analyze the importance of the information available in the operator process of maintenance of electrical networks to offer for the company SODINLEC LTDA, for the opportunity take decisions what support and promoted the continuous improvement process of the company, identify the negative impact what cause of the absence of the data for measurement of the quality and efficiency in the realization the activities associated to the services provided
- …