449 research outputs found
Design of a low-cost electrical resistivity meter for near surface surveys
A programmable automated electrical resistivity meter was designed and constructed. The device was created to perform near surface studies, particularly for archaeogeophysical target characterization. Real field and laboratory model studies can be performed changing the current input of the device. The equipment consists of two independent devices, each one with its own microcontroller platform. They are interconnected through serial data transfer protocol. The first device, works as a resistivity meter where the ABMN electrode positions are programmed and permits the interaction with the user. The second one, connects the current and voltage channels to the programmed electrode positions. A physical model and field measurements were performed with different electrode configurations such as Dipole-Dipole, Werner-Schlumberger and Wenner γ112 in order to verify the performance of the automated electrical resistivity meter. The measurements give mean relative standard deviation values between 0.6% and 5.5% and data inversion convergence between 1.3% and 7.2%. Even though this open source and low cost electrical resistivity meter was design primarily for archaeogeophysical studies, it could be adapted to other geophysical issues such as contamination plumes detection and characterization, tunnel detection, etc.Fil: de la Vega, Matias. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Física de Buenos Aires. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Física de Buenos Aires; Argentina. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de Física. Grupo de Geofísica Aplicada; ArgentinaFil: Bongiovanni, Maria Victoria Flavia. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Austral. Facultad de Ingeniería. Laboratorio de Investigación Desarrollo y Transferencia - Comisión de Investigaciones Científicas de la Provincia de Buenos Aires. Laboratorio de Investigación Desarrollo y Transferencia; ArgentinaFil: Grünhut Duenyas, Vivian. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Austral. Facultad de Ingeniería. Laboratorio de Investigación Desarrollo y Transferencia - Comisión de Investigaciones Científicas de la Provincia de Buenos Aires. Laboratorio de Investigación Desarrollo y Transferencia; Argentin
Electrical imaging for localizing historical tunnels at an urban environment
We performed a geophysical study at a historical site in Buenos Aires, Argentina, corresponding to the location of a Jesuit Mission established during the 17th century, remaining there until the 18th century. The site consisted of a church, cloisters, a school, orchards and a procurator’s office; also several tunnels were built, connecting the mission with different public buildings in the town. In the 19th century the Faculty of Sciences of the University of Buenos Aires was built in a sector of the site originally occupied by an orchard, functioning until its demolition in 1973. At present, this area is a cobbled square. With the aim of preserving and restoring the buried structures, work was carried out in this square looking for tunnels and remains of the basement of the old building. Considering the conductive features of the subsoil, mainly formed by clays and silt, the complex characteristics of the buried structures, and the urban localization of the study area with its consequent high level of environmental electromagnetic noise, we performed prefeasibility studies to determine the usefulness of different geophysical methods. The best results were achieved from the geoelectrical method. Dipole–dipole profiles with electrode spacings of 1.5 and 3m provided enough lateral and vertical resolution and the required penetration depth. Reliable data were obtained as long as the electrodes were buried at least 15 cm among the cobble stones. Nine 2D electrical resistivity tomographies were obtained by using a robust inversion procedure to reduce the effect of possible data outliers in the resulting models. The effect on these models of different error estimations was also analyzed. Then, we built up a pseudo-3D model by laterally interpolating the 2D inversion results. Finally, by correlating the resulting model with the original plans, the remains of the expected main structures embedded in the site were characterized. In addition, an anomaly was identified that indicates the presence of a tunnel not previously reported.Fil: Osella, Ana. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de Física. Grupo de Geofísica Aplicada; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Física de Buenos Aires. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Física de Buenos Aires; ArgentinaFil: Martinelli, Hilda Patricia. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Física de Buenos Aires. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Física de Buenos Aires; Argentina. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de Física. Grupo de Geofísica Aplicada; ArgentinaFil: Grunhut, Vivian. Universidad de San Andrés. Departamento de Matemáticas y Ciencias; ArgentinaFil: de la Vega, Matias. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Física de Buenos Aires. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Física de Buenos Aires; Argentina. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de Física. Grupo de Geofísica Aplicada; ArgentinaFil: Bonomo, Nestor Eduardo. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de Física. Grupo de Geofísica Aplicada; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Física de Buenos Aires. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Física de Buenos Aires; ArgentinaFil: Weissel, Marcelo Norman. Universidad Nacional de Lanus. Departamento de Humanidades y Artes; Argentin
Agências, agentes e âmbitos de socialização política: pesquisa desde relatos de vida em ativistas universitarios/as
El presente trabajo se propuso precisar el rol de agencias, agentes y ámbitos en el proceso de socialización política de estudiantes-militantes de la Universidad Nacional de Córdoba (Argentina). Se realizó un estudio cualitativo descriptivo con 18 estudiantes de ambos sexos. Se realizaron entrevistas abiertas y en profundidad, utilizando la perspectiva de los relatos de vida. Se efectuó un análisis de contenido cualitativo temático. Los resultados resaltan la importancia de la familia, la escuela y el grupo de pares en el aprendizaje político. A su vez, se discute el rol de la Universidad pública como agencia y ámbito de socialización política.The present investigation aimed to determine the role of agents, agencies and contexts in the political socialization process of activists-students from National University of Cordoba (Argentina). A qualitative and descriptive study with 18 students of both sexes was carried out. Open and in-depth interviews, using life narratives approach, were made. A qualitative and thematic content analysis was performed. Results highlight the importance of family, school and pair groups in political learning. At the same time, public university role as agency and sphere of political socialization is discussed.O presente trabalho procurou especificar o papel de agências, agentes e âmbitos no processo de socialização política de estudantes-militantes da Universidade Nacional de Córdoba (Argentina). Foi realizado um estudo qualitativo descritivo com 18 estudantes de ambos os sexos. Entrevistas abertas e aprofundadas foram realizadas, utilizando a perspectiva das histórias de vida. Foi efetuada uma análise do conteúdo qualitativo temático. Os resultados destacam a importância da família, escola e grupo de pares na aprendizagem política. Por sua vez, é discutido o papel da universidade pública como agência e âmbito da socialização política.Fil: De La Vega, Joaquín. Universidad Nacional de Córdoba. Facultad de Psicología; ArgentinaFil: Bazán, Alejandro Mario. Universidad Nacional de Córdoba. Facultad de Psicología; ArgentinaFil: Imhoff, Débora Soledad. Universidad Nacional de Córdoba. Instituto de Investigaciones Psicológicas. - Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Investigaciones Psicológicas; ArgentinaFil: Dreizik, Matias Alfredo. Universidad Nacional de Córdoba. Instituto de Investigaciones Psicológicas. - Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Investigaciones Psicológicas; Argentin
Trajetórias de Militâncias e processos de socialização política de estudantes universitarios de Córdoba (Argentina)
La investigación indagó las características que adquiere el proceso de socialización política entre estudiantes-militantes de tres unidades académicas de la Universidad Nacional de Córdoba, Argentina. Se realizó un estudio cualitativo de alcance descriptivo. Se recuperó la perspectiva biográfica de los relatos de vida a través de la realización de 18 entrevistas a universitarios/as que participan con más de tres meses de antigüedad en agrupaciones estudiantiles o centros de estudiantes. Los datos fueron analizados mediante análisis de contenido cualitativo, considerando los ejes de indagación de las entrevistas. Los resultados permitieron reflexionar sobre la articulación de aprendizajes latentes y manifiestos basados en experiencias políticas previas. A su vez, se identificaron tres tipos de trayectorias de militancia en la narrativa de estos/as estudiantes, que dan cuenta de la pluralidad y diversidad del fenómeno.This research investigated the characteristics of a political socialization process in a group of student activists from three academic areas of the National University of
Córdoba, Argentina. An empirical and descriptive qualitative study was conducted as part of the research process and the biographical perspective of students’ life stories was recovered. 18 interviews were conducted with university students who had been involved in student political organizations or student unions for at least three months. The data was analyzed using qualitative content analysis. The results led to a reflection on the articulation of latent and evident political learning that was based on previous political experiences. It was also possible to recognize three different types of political activism trajectories in the narratives of these students, accounting for the plurality and diversity of this phenomenon.A investigação pesquisou as características que possui o processo de socialização política em estudantes-militantes de três unidades académicas da Universidade Nacional de Córdoba, Argentina. Um estudo empírico qualitativo de alcance descritivo foi feito. Recuperou-se a perspectiva biográfica dos relatos de vida a través da realização de 18 entrevistas a universitários/ as que participam há mais de três meses em agrupações estudantis ou grêmios de estudantes. Os dados foram analisados mediante uma análise de conteúdo qualitativo, considerando os eixos de
indagação das entrevistas. Os resultados permitiram refletir sobre a articulação das aprendizagens latentes e manifestas baseadas nas experiências políticas prévias. Ao mesmo tempo, se identificaram três tipos de trajetórias de militância na narrativa dos/as estudantes, que dão conta da pluralidade e diversidade do fenómeno.Fil: Bazán Alejandro. Universidad Nacional de Córdoba. Facultad de Psicología; ArgentinaFil: De La Vega, Joaquín. Universidad Nacional de Córdoba. Facultad de Psicología; ArgentinaFil: Dreizik Matias. Universidad Nacional de Córdoba. Facultad de Psicología; ArgentinaFil: Imhoff, Débora Soledad. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Centro de Investigaciones y Estudio sobre Cultura y Sociedad. Centro de Investigaciones de la Facultad de Psicología - Grupo Vinculado CIPSI; Argentin
GPR prospection to locate a water well and a gallery in an urban historical site
En este trabajo se presentan las metodologías y los resultados de una prospección geofísica realizada con GPR en la Manzana de las Luces (Buenos Aires, Argentina), cuyo principal objetivo fue localizar con precisión una cisterna y una galería, construidas durante los siglos XVII-XVIII. Otro objetivo fue detectar estructuras de origen más reciente, tales como partes del piso y tuberías. Esta información resultará útil para la planificación de intervenciones arqueológicas en el lugar, y contribuirá a la preservación de dichas estructuras históricas, frente a obras arquitectónicas o de ingeniería civil que puedan realizarse en un futuro. Desde el punto de vista geofísico, el sitio estudiado presenta una capa de suelo con contenidos de arcilla y humedad apreciables, lo que implicaba niveles medios a altos de atenuación de las ondas de GPR y, consecuentemente, limitada penetración. Asimismo, el sitio se encuentra en un ámbito urbano, con proliferación de objetos cercanos –tanto en el suelo como en el aire- y fuentes variadas de radiofrecuencia, lo cual anticipaba la posibilidad de obtener secciones de datos complejas, con reflexiones numerosas y próximas entre sí, con formas e intensidades diversas. Estas características requerían alcanzar un buen nivel de resolución en las secciones de datos para que dichas reflexiones pudieran ser distinguidas y correctamente interpretadas. Para eso era necesario tener ciertos recaudos, especialmente al momento del diseño de la prospección y durante el análisis e interpretación de los datos. La realización de pruebas previas a la prospección definitiva permitió definir un conjunto de parámetros de medición que hizo posible detectar reflexiones con amplitudes intermedias y bajas, con buena definición de las mismas. Además, la representación simultánea de los datos en las formas de secciones verticales y plantas favoreció la detección de reflexiones que, en principio, eran detectables en sólo una de estas formas de representación. Las reflexiones detectadas mediante ambos tipos de gráficos fueron correlacionadas entre sí, clasificadas y finalmente interpretadas en términos de sus probables orígenes. La metodología empleada permitió determinar las ubicaciones de la cisterna y la galería, con una precisión de unos pocos centímetros. También se detectaron tuberías, así como diversas discontinuidades y una malla de refuerzo en la estructura del piso. Los objetos que fueron centro de esta investigación y el tipo de entorno descrito resultan comunes a distintos sitios arqueológicos de Argentina y el exterior. En este sentido, los procedimientos y resultados mostrados sirven como un ejemplo o caso de referencia al respecto. Un objetivo particular del trabajo es revelar la utilidad y las limitaciones de la metodología empleada, en relación con las condiciones que imponen el tipo de aplicación y entorno. Otros objetivos son ilustrar los distintos tipos de reflexiones que pueden obtenerse en estos casos, y mostrar un análisis pormenorizado de las mismas y sus interpretaciones en términos de los probables orígenes. Es de esperar que estos contenidos resulten de interés para aquellas personas que trabajan con GPR en esta clase de sitios, así como para colegas con un interés más general en estas temáticas.This paper describes the methods and results of a geophysical survey carried out with GPR at the historical site “Manzana de las Luces”, located in the city of Buenos Aires, Argentina, whose main objective was to pinpoint a cistern and a gallery built during the 17th and 18th centuries. Another objective was to detect newer structures, such as parts of the floor and pipelines. The search was prompted by the need to have useful information for planning archaeological research and conservation actions. Besides, the results of the study will contribute to the preservation of the historic structures against possible architectural or civil engineering works that can be performed in the future. From the geophysical viewpoint, the site has a layer of soil with significant clay and moisture contents, which implied intermediate to high attenuation of the GPR waves and, consequently, limited penetration. Moreover, the site is in an urban area with nearby objects -located in the soil and air - and varied sources of radio frequency, which anticipated the possibility of obtaining complex data sections with numerous and close reflections, with different shapes and intensities. The expected characteristics for the reflections due to objects of interest and the proximity of events required a good resolution level in the data sections so that the main reflections could be distinguished and interpreted correctly. That made necessary to take some precautions, especially at the time of survey design and during the analysis and interpretation of the data. Tests performed before the definitive prospecting allowed defining a set of measurement parameters that made possible to detect intermediate to low- amplitude reflections with good definition. Furthermore, the simultaneous representation of the data in the forms of vertical sections and constant-time/horizontal slices favored detecting reflections that in principle were detectable in only one of these forms of representation. The reflections detected from these types of graphs were correlated between them, classified and finally interpreted in terms of their probable origins. This methodology allowed determining the locations of the cistern and the gallery with an accuracy of a few centimeters, as well as detecting floor discontinuities, different pipelines and the presence of a thin mesh in the floor structure. The types of investigated objects and environmental conditions in this study are common to different archaeological sites in Argentina and other countries. In this regard, the procedures and results shown in this paper serve as an example or reference case. A particular goal of this paper is to demonstrate the usefulness and limitations of the applied methodology, in relation to the conditions imposed by the type of application and environment. Other objectives are to illustrate the different types of reflections that can be obtained in these cases, to show a detailed analysis of these reflections and their interpretation in terms of probable origins. It is expected that these contents will be of interest to people working with GPR in this kind of sites, as well as other colleagues with a more general interest in these topics.Fil: Bonomo, Nestor Eduardo. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Física de Buenos Aires. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Física de Buenos Aires; Argentina. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de Física; ArgentinaFil: Martinelli, Hilda Patricia. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de Física; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Física de Buenos Aires. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Física de Buenos Aires; ArgentinaFil: Osella, Ana Maria. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de Física; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Física de Buenos Aires. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Física de Buenos Aires; ArgentinaFil: de la Vega, Matias. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Física de Buenos Aires. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Física de Buenos Aires; Argentina. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de Física; Argentin
Correction: Dueñas et al. Assessing effectiveness of colonic and gynecological risk reducing surgery in Lynch syndrome individuals. Cancers 2020, 12, 3419.
In the original article, there was a mistake in Figure 3 as published [1]. The image presented corresponded to endometrial cancer-specific mortality cumulative incidence, instead of the figure referred to in the title (all-cause mortality cumulative incidence)
Impact of COVID-19 on cardiovascular testing in the United States versus the rest of the world
Objectives: This study sought to quantify and compare the decline in volumes of cardiovascular procedures between the United States and non-US institutions during the early phase of the coronavirus disease-2019 (COVID-19) pandemic.
Background: The COVID-19 pandemic has disrupted the care of many non-COVID-19 illnesses. Reductions in diagnostic cardiovascular testing around the world have led to concerns over the implications of reduced testing for cardiovascular disease (CVD) morbidity and mortality.
Methods: Data were submitted to the INCAPS-COVID (International Atomic Energy Agency Non-Invasive Cardiology Protocols Study of COVID-19), a multinational registry comprising 909 institutions in 108 countries (including 155 facilities in 40 U.S. states), assessing the impact of the COVID-19 pandemic on volumes of diagnostic cardiovascular procedures. Data were obtained for April 2020 and compared with volumes of baseline procedures from March 2019. We compared laboratory characteristics, practices, and procedure volumes between U.S. and non-U.S. facilities and between U.S. geographic regions and identified factors associated with volume reduction in the United States.
Results: Reductions in the volumes of procedures in the United States were similar to those in non-U.S. facilities (68% vs. 63%, respectively; p = 0.237), although U.S. facilities reported greater reductions in invasive coronary angiography (69% vs. 53%, respectively; p < 0.001). Significantly more U.S. facilities reported increased use of telehealth and patient screening measures than non-U.S. facilities, such as temperature checks, symptom screenings, and COVID-19 testing. Reductions in volumes of procedures differed between U.S. regions, with larger declines observed in the Northeast (76%) and Midwest (74%) than in the South (62%) and West (44%). Prevalence of COVID-19, staff redeployments, outpatient centers, and urban centers were associated with greater reductions in volume in U.S. facilities in a multivariable analysis.
Conclusions: We observed marked reductions in U.S. cardiovascular testing in the early phase of the pandemic and significant variability between U.S. regions. The association between reductions of volumes and COVID-19 prevalence in the United States highlighted the need for proactive efforts to maintain access to cardiovascular testing in areas most affected by outbreaks of COVID-19 infection
Use of anticoagulants and antiplatelet agents in stable outpatients with coronary artery disease and atrial fibrillation. International CLARIFY registry
Burnout among surgeons before and during the SARS-CoV-2 pandemic: an international survey
Background: SARS-CoV-2 pandemic has had many significant impacts within the surgical realm, and surgeons have been obligated to reconsider almost every aspect of daily clinical practice. Methods: This is a cross-sectional study reported in compliance with the CHERRIES guidelines and conducted through an online platform from June 14th to July 15th, 2020. The primary outcome was the burden of burnout during the pandemic indicated by the validated Shirom-Melamed Burnout Measure. Results: Nine hundred fifty-four surgeons completed the survey. The median length of practice was 10 years; 78.2% included were male with a median age of 37 years old, 39.5% were consultants, 68.9% were general surgeons, and 55.7% were affiliated with an academic institution. Overall, there was a significant increase in the mean burnout score during the pandemic; longer years of practice and older age were significantly associated with less burnout. There were significant reductions in the median number of outpatient visits, operated cases, on-call hours, emergency visits, and research work, so, 48.2% of respondents felt that the training resources were insufficient. The majority (81.3%) of respondents reported that their hospitals were included in the management of COVID-19, 66.5% felt their roles had been minimized; 41% were asked to assist in non-surgical medical practices, and 37.6% of respondents were included in COVID-19 management. Conclusions: There was a significant burnout among trainees. Almost all aspects of clinical and research activities were affected with a significant reduction in the volume of research, outpatient clinic visits, surgical procedures, on-call hours, and emergency cases hindering the training. Trial registration: The study was registered on clicaltrials.gov "NCT04433286" on 16/06/2020
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