242 research outputs found

    Finding patterns of atoll morphometrics at a range of spatial scales

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    Small Island Nations, often comprised of Atolls, are at considerable risk of climate change impacts from sea-level rise to coral acidification to increasing cyclone intensity; understanding how they will change in the coming century is vital for climate mitigation and resiliency. However, the morphology of atolls are not well quantified or summarized. In this work, we calculate modern atoll morphometrics on a global scale including 3,786 motu and 593 reef flats on 154 atolls. Temporal composites of Landsat imagery are created for 4 years (2015–2018), and are classified into motu, reef flat, open water/lagoon via unsupervised classification. Morphometrics, including widths, lengths, and area, are computed for each motu and reef flat of the atoll in Python, creating a database of atolls and their associated morphometrics. Consistency in automated processing of atoll morphometrics removes spatial and user bias, enabling a better understanding of geographic patterns of atoll area and other morphometrics. Distinct differences in the distribution of motu are seen on a regional scale in French Polynesia, while globally, wider reef flats and larger motu are found closest to the equator. Globally, there is a consistent reef flat width in front of large motu (>1 km length) of 184 ± 93 m (n = 724). Our atoll morphometric database creates a baseline of current atoll characteristics that can be expanded upon in the future and used for evaluating temporal changes to atoll islands

    Investigation of the effect of a circular patch of vegetation on turbulence generation and sediment deposition using four case studies

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    Submitted in partial fulfillment of the requirements for the degree of Master of Science at the Massachusetts Institute of Technology and the Woods Hole Oceanographic Institution June 2012This study describes the spatial distribution of sediment deposition in the wake of a circular patch of model vegetation and the effect of the patch on turbulence and mean flow. Two difference types pf vegetation were used along with two different stem densities totaling four different case studies. The spatial location of enhanced deposition correlated with the steady wake zone, which has length, L1. The steady wake zone only occurred downstream of the rigid emergent patches of vegetation and was not seen downstream of the flexible submerged patches of vegetation. The enhanced deposition occurred when both turbulence and mean velocity was below the upstream, initial values. The enhanced deposition occurred when the mean velocity was less than or equal to half of the initial velocity. For the four cases studied, theses parameters of low velocity and low turbulence were primarily met within the steady wake region immediately downstram of the two rigid emergent patches of vegetation. In all four cases, large coherent structures are created in the flow due to the patch. Lateral vortices are formed downstream of the patch in a von-Karman vortex street that meets at the center of the flow a distance, Lw, downstream of the patch. For the flexible submerged cases, streamlines reattach to the bed of the flume a distance, Lv, downstream of the patch. In addition, for the flexible submerged cases, a secondary circulation is generated with flow moving laterally away from the patch at the surface and toward the centerline of the patch at the bed.This material is based upon work supported by the National Science Foundation under Grant Nos. EAR 0738352 and OCE 0751358

    Transverse. Art projection space a public that is trained in art maybe a less violent public

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    Este articulo recopila algunos testimonios de varios integrantes que consolidan en palabras sus apreciaciones más significativas de estos cuatro años de estar presentes en el proyecto Espacio Transverso, del grupo de investigación TEI (Teatro espacio & interactividad) y su semillero llamado de la misma forma TEI. Compartiendo con los lectores fragmentos de reflexiones del proceso vivencial y su importancia en la proyección artística de la ciudad, Facultad de Bellas Artes en la Universidad del Atlántico, premisas a partir de la búsqueda por los integrantes y su principal impacto en la académica y en el arte; como proyecto de proyección y extensión hacia la comunidad del caribe colombiano para generar público y espacialmente mirarlo desde la práctica de circulación hecho que para los artistas es fundamental en el ámbito académico entre estudiantes, docentes y egresados para el transcurso del proyecto entre teoría y práctica artística para un público menos violento .This article collet some testimonials from several members that consolidate in words their appreciations most significant from these four years of being present in Espacio Transverso project, from investigation group TEI (Theater, Space & Interactivity) and its seedbed called equally TEI.Sharing with the readers fragments of reflections of the vivencial project and its importance in the artistic projection of the city, Facultad de Bellas Artes in Universidad del Atlántico, premises from the search by the integrants and their main impact in the academy and in art; as projection project and extension towards community of the Colombian caribbean to generate audience and especially view it since the practice of circulation, a fact that for artists is fundamental in the academic field among students, teachers and graduates for the course of the project between theory and artistic practice for a less violent audience

    Validation of the instrument Gender Sensitivity in Teaching Practice from the university student perspective

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    La desigualdad, inequidad y violencia de género en la educación superior son incómodos y difícil de manejar en las instituciones. En la universidad, como institución social, existen prácticas docentes que pueden reforzar, mantener, producir y reproducir los estereotipos de género o bien ayudar a modificar y colaborar con su deconstrucción. De ahí la importancia de saber cómo el estudiantado percibe estos estereotipos desde el actuar docente. Sin embargo, en la literatura revisada se observó escasez de instrumentos que permitan dar cuenta de ello. Por lo tanto, el objetivo fue el desarrollo y validación de un instrumento diseñado para medir la sensibilidad de género en las prácticas docentes a nivel superior, desde la perspectiva del estudiantado. Tal instrumento comprende cuatro dimensiones: 1) apoyo emocional, 2) manejo de conducta, 3) apoyo pedagógico y 4) lenguaje. La validación se realizó en dos fases, la primera por juezas expertas, las cuales valoraron la pertinencia y claridad de los reactivos y se calculó la razón de validez de contenido para cada uno. En la segunda, se realizó un estudio piloto con una muestra de 870 estudiantes de licenciatura para determinar las propiedades psicométricas de las dimensiones del instrumento. Se realizaron análisis factoriales exploratorios y confirmatorios y de consistencia interna a través del coeficiente alfa de Cronbach. Los resultados mostraron que las dimensiones tienen una buena estructura factorial y confiabilidad, lo cual indica que puede usarse en el ámbito universitario. La versión final del instrumento quedó conformada por 31 ítems en formato Likert y una pregunta abierta.Inequality, inequity and gender violence in higher education are uncomfortable and difficult to handle in institutions. In the university as a social institution there are teaching practices that can reinforce, maintain, produce and reproduce gender stereotypes or help modify and collaborate with their deconstruction. Hence the importance of knowing how the student perceives these stereotypes from the teaching act. However, in the reviewed literature, a shortage of instruments was observed to be considered for this. Therefore, the objective was the development and validation of an instrument designed to measure gender sensitivity in teaching practices at a higher level, from the perspective of the students. This instrument comprises four dimensions: 1) emotional support, 2) behavior management, 3) pedagogical support, and 4) language. Validation was carried out in two phases, the first by expert judges, who assessed the relevance and clarity of the items and calculated the content validity ratio for each one. In the second, a pilot study was carried out with a sample of 870 higher level students to determine the psychometric properties of the instrument’s dimensions. Exploratory and confirmatory factor analyzes and internal consistency and were carried out through Cronbach’s alpha coefficient. The results showed that the dimensions have a good factorial structure and reliability, which indicates that it can be used in the university environment. The final version of the instrument was made up of 31 items in Likert format and one open question

    Metallic elements in foliar material and fruits of three tree species as bioindicators

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    This study aimed to determine the presence of metal elements in fruits and leaves of three tree species as bioindicators in San Luis Potosi, Mexico. Ninety fruit and 90 leaf samples (30 per tree species) were collected at five sites (agricultural, suburban, commercial and services, urban, and mining), using the site and the presence of P. laevigata, S. molle, and A. farnesiana as references. Total concentrations of 13 metal elements were determined using an inductively coupled plasma mass spectrometer (ICP-MS). The species were significantly affected by Co, As, and Pb (ANOVA, p≤0.05). Considering the land use and the species, the contents determined in the leaves and fruits of the three species had sufficient and phytotoxic contents of Al, Cd, Co, Ni, Mn, Ti, and Cr, and excessive ranges with the possible phytotoxic effect of As, Cu, Pb, Zn, V, and Fe. The A. farnesiana had the highest concentrations of 12 heavy metals analyzed (HM). The variation in total metal concentrations between leaves and fruits ranged from 84.70 to 99.06%, with V, As, and Cr being prominent. The functionality of these tree species as phytoremediators and bioindicators is reviewed to evaluate environmental impacts on land use. Highlights Tree species represent a potential bioindicator for studying environmental pollutants due to their ability to accumulate heavy metals. The variation in total metal concentrations between leaves and fruits ranged from 84.70 to 99.06% The contents determined in the leaves and fruits of the three species trees had sufficient and phytotoxic HM contents. The tree species have phytoremediators capacity to evaluate environmental impacts and environmental contamination of land use.This study aimed to determine the presence of metal elements in fruits and leaves of three tree species as bioindicators in San Luis Potosi, Mexico. Ninety fruit and 90 leaf samples (30 per tree species) were collected at five sites (agricultural, suburban, commercial and services, urban, and mining), using the site and the presence of P. laevigata, S. molle, and A. farnesiana as references. Total concentrations of 13 metal elements were determined using an inductively coupled plasma mass spectrometer (ICP-MS). The species were significantly affected by Co, As, and Pb (ANOVA, p≤0.05). Considering the land use and the species, the contents determined in the leaves and fruits of the three species had sufficient and phytotoxic contents of Al, Cd, Co, Ni, Mn, Ti, and Cr, and excessive ranges with the possible phytotoxic effect of As, Cu, Pb, Zn, V, and Fe. The A. farnesiana had the highest concentrations of 12 heavy metals analyzed (HM). The variation in total metal concentrations between leaves and fruits ranged from 84.70 to 99.06%, with V, As, and Cr being prominent. The functionality of these tree species as phytoremediators and bioindicators is reviewed to evaluate environmental impacts on land use. Highlights Tree species represent a potential bioindicator for studying environmental pollutants due to their ability to accumulate heavy metals. The variation in total metal concentrations between leaves and fruits ranged from 84.70 to 99.06% The contents determined in the leaves and fruits of the three species trees had sufficient and phytotoxic HM contents. The tree species have phytoremediators capacity to evaluate environmental impacts and environmental contamination of land use

    Metales pesados en polvo atmosférico depositado en hojas de Acacia farnesiana (Fabaceae) y Prosopis laevigata (Fabaceae)

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    Atmospheric dust establishes an element of study to know the distribution of pollutant particles such as heavy metals and their effects on ecological systems. The objective was to determine the elemental composition of particles deposited in two species of trees as an indicator of environmental impact in San Luis Potosí, México. The distribution of Acacia farnesiana and Prosopis laevigata trees was taken into account in five soil uses to collect leaf material and extract atmospheric dust during the spring and summer seasons, determining the concentration of heavy metals using the ICP-MS technique. The results indicated the presence of Al> Cu> Zn> Pb> V> As> Ni> Cd> Ti> Cr> Co. Correlations with values of r2> 0.90 were presented between V-Ti, Ni-V, Ni-Ti, Al-Ti and Cr-V. The species factor conditioned the concentrations of Al, Ti, V, Cr, Ni and Zn mainly in the particles deposited in Prosopis leaves. Particles of nine elements were conditioned by the activities of the five land uses, where the use of mineral soil affected by the presence of Al, Cd, Co, Pb, Cu and Zn. Concentrations of Cd were 6.2 times higher in the use of mining soil than in the agricultural sector; 5.9 and 5.4 times the concentrations of Co and Pb in the use of mining soil with respect to the trade and service respectively. The season had only significant effects on Cr and Pb particles. This study indicates the existence of pollutants that can affect ecological systems so it falls within the context of continued evaluation of environmental impacts.El polvo atmosférico se establece como elemento de estudio para conocer la distribución de partículas contaminantes, como son los metales pesados y sus efectos sobre los sistemas ecológicos. El objetivo fue determinar la composición elemental de las partículas depositadas en dos especies de árboles como un indicador de impacto ambiental en San Luis Potosí, México. La distribución de los árboles de Acacia farnesiana y Prosopis laevigata se tomó en cuenta en cinco usos del suelo para recolectar material foliar y extraer el polvo atmosférico durante la primavera y el verano, determinando la concentración de metales pesados utilizando la técnica ICP-MS. Los resultados indicaron la presencia de Al> Cu> Zn> Pb> V> As> Ni> Cd> Ti> Cr> Co. Se presentaron correlaciones con valores de r2> 0,90 entre V-Ti, Ni-V, Ni-Ti, Al-Ti y Cr-V. El factor especie condicionó las concentraciones de Al, Ti, V, Cr, Ni y Zn principalmente en las partículas depositadas en las hojas de Prosopis. Las partículas de nueve elementos fueron condicionadas por las actividades de los cinco usos de la tierra, donde el uso del suelo mineral se vio afectado por la presencia de Al, Cd, Co, Pb, Cu y Zn. Las concentraciones de Cd fueron 6,2 veces más altas en el uso de suelo minero que en el sector agrícola; 5,9 y 5,4 veces las concentraciones de Co y Pb en el uso del suelo minero con respecto al comercio y al servicio, respectivamente. La temporada solo tuvo efectos significativos sobre las partículas de Cr y Pb. Este estudio indica la existencia de contaminantes que pueden afectar los sistemas ecológicos, por lo que entran en el contexto de la evaluación de los impactos ambientales.Fil: Jorge Alcalá Jáuregui. Universidad Autónoma de San Luis Potosí. Facultad de AgronomíaFil: Juan C. Rodríguez Ortiz. Universidad Autónoma de San Luis Potosí. Facultad de AgronomíaFil: Alejandra Hernández Montoya. Universidad Autónoma de San Luis Potosí. Facultad de AgronomíaFil: María Flavia Filippini. Universidad Nacional de Cuyo. Facultad de Ciencias AgrariasFil: Eduardo Martinez Carretero. Instituto Argentino de Investigaciones de las Zonas Áridas Fil: Paola Elizabeth Díaz Flores. Universidad Autónoma de San Luis Potosí. Facultad de AgronomíaFil: Ángel Natanael Rojas Velázquez. Universidad Autónoma de San Luis Potosí. Facultad de AgronomíaFil: Humberto Rodríguez-Fuentes. Universidad Autónoma de Nuevo León (México). Facultad de Agronomía.Fil: Félix Alfredo Beltrán Morales. Universidad Autónoma de Baja California Sur (México

    Vegetación bioindicadora de metales pesados en un sistema semiárido

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    The evaluation of pollution by heavy metals on ecosystems can determine the bioindicative capacity of plant species. The presence of heavy metals was determined in Prosopis laevigata, Acacia spp. and Schinus molle under the effect of different of land uses and seasons. The area is located near of the municipalities of Soledad de Graciano Sánchez and San Luis Potosi which has fragmented land use such as: agriculture, commercial and services, urban residential and mining. Samples were taken from leaves of the three species during summer, autumn, winter and spring to assess the concentrations of heavy metals through the technique of ICP-MS. Statistical analyzes showed levels of Aluminum (Al) > Zinc (Zn) > Lead (Pb) > Copper (Cu) > Titanium (Ti) > Vanadium (V) > Arsenic (As) > Chromium (Cr) > Cadmium (Cd) > Cobalt (Co). The elements Al, As, Cd, Cr, Pb and Ti had levels above the normal threshold in vegetation. Land use had a significant effect with Al, Ti, Cd, As and Pb having the trees being located in the land with mining and commercial and services use the greater concentrations. The species had a significant effect on Al and Pb with Acacia spp., having the largest storage capacity. The season of the year significantly impacted the accumulation of As, Cd, Co, Cu, Cr and Ti in the three species. The anthropogenic dynamics of different land uses generated waste particles and residues of heavy metals, impacting the availability and accumulation in the species evaluated. This study contribute to evaluate the environmental impact in the system with a fragmented land use and the continuation of this type of studies is recommended.Evaluar la contaminación por metales pesados en los ecosistemas permite conocer la capacidad bioindicativa de especies vegetativas. El objetivo fue determinar la concentración de metales pesados en Prosopis laevigata, Acacia spp. y Schinus molle bajo el efecto de usos suelo y temporalidad. El área se sitúa en la colindancia de los Municipios de Soledad de Graciano Sánchez y San Luis Potosí fragmentada por usos de suelo: agropecuario, comercio y servicios, residencial urbano y minero. Fueron tomadas muestras de hojas de las tres especies en las estaciones de verano, otoño, invierno y primavera y se evaluó la concentración de metales pesados a través de la técnica de ICP-MS. Los análisis estadísticos indicaron niveles de Aluminio (Al) > Cinc (Zn) > Plomo (Pb) > Cobre (Cu) > Titanio (Ti) > Vanadio (V) > Arsénico (As) > Cromo (Cr) > Cadmio (Cd) > Cobalto (Co). Los elementos Al, As, Cd, Cr, Pb y Ti presentaron niveles por encima del umbral normal en vegetación. El uso de suelo tuvo efecto significativo con Al, Ti, Cd, As y Pb; los árboles ubicados en los usos de suelo minero, comercio y servicios tuvieron la mayor concentración. La especie tuvo efecto significativo con Al y Pb siendo Acacia spp. el que presentó la mayor capacidad de acumulación. La temporada del año impactó significativamente en la acumulación de As, Cd, Co, Cu, Cr y Ti en las tres especies. La dinámica antropogénica de los diferentes usos de suelo genera partículas y residuos con metales pesados impactando en la disponibilidad y acumulación en las especies evaluadas. Se contribuye a evaluar el impacto ambiental en el sistema fragmentado recomendando dar continuidad a este tipo de estudios

    Overview and characterization of penile cancer content across social media platforms

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    BackgroundSocial media platforms (SMP) are an emerging resource that allows physicians, patients, and families to converse on cancer prevention, diagnosis, and treatment. We aimed to characterize penile cancer (PC) content shared on SMP.MethodsWe searched PC posts on Twitter, Facebook, and Instagram from July 1st, 2021, through June 30th, 2022. Two independent, blinded reviewers analyzed the hashtags: #PenileCancer, #PenileCancerAwareness, and #PenileNeoplasm. Descriptive statistics were used for posts characterization, Pearson´s correlation coefficient for associations, and Cohen’s weighted kappa coefficient for inter-rater agreement rate.ResultsA total of 791 posts were analyzed, with Twitter accounting for 52%, Facebook for 12.2%, and Instagram for 35.5%, and. Most posts originated from high-income countries, such as the United Kingdom (48.8%). We found no correlation between the number of posts with PC incidence (p = 0.64) or users on SMP (p = 0.27). Most accounts were classified as “support and awareness communities” (43.6%) and “physicians and clinical researchers” (38.2%). Urology was the most common medical specialty to post (60.9%), followed by oncology (11.3%). Most posts were classified as “prevention and awareness for users” (45.1%). Global inter-reviewer agreement rate was almost perfect (k=0.95; p ≤ 0.01). On Twitter, “physicians and clinical researchers” shared more content on “treatment updates and medical papers published in medical journals,” while on Facebook and Instagram, “support and awareness communities” focused on “personal and support comments.”ConclusionOverall, the number of PC posts was low compared to other neoplasms across the SMP evaluated in this study. “Physicians and clinical researchers” shared more content on Twitter, while “support and awareness communities” on Facebook and Instagram. Encouraging the use of a common SMP among the medical community and general users could lead to a more effective communication between physicians, patients, and support groups, and to increased awareness of PC
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