130 research outputs found

    Interest communities and flow roles in directed networks: the Twitter network of the UK riots

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    Directionality is a crucial ingredient in many complex networks in which information, energy or influence are transmitted. In such directed networks, analysing flows (and not only the strength of connections) is crucial to reveal important features of the network that might go undetected if the orientation of connections is ignored. We showcase here a flow-based approach for community detection in networks through the study of the network of the most influential Twitter users during the 2011 riots in England. Firstly, we use directed Markov Stability to extract descriptions of the network at different levels of coarseness in terms of interest communities, i.e., groups of nodes within which flows of information are contained and reinforced. Such interest communities reveal user groupings according to location, profession, employer, and topic. The study of flows also allows us to generate an interest distance, which affords a personalised view of the attention in the network as viewed from the vantage point of any given user. Secondly, we analyse the profiles of incoming and outgoing long-range flows with a combined approach of role-based similarity and the novel relaxed minimum spanning tree algorithm to reveal that the users in the network can be classified into five roles. These flow roles go beyond the standard leader/follower dichotomy and differ from classifications based on regular/structural equivalence. We then show that the interest communities fall into distinct informational organigrams characterised by a different mix of user roles reflecting the quality of dialogue within them. Our generic framework can be used to provide insight into how flows are generated, distributed, preserved and consumed in directed networks.Comment: 32 pages, 14 figures. Supplementary Spreadsheet available from: http://www2.imperial.ac.uk/~mbegueri/Docs/riotsCommunities.zip or http://rsif.royalsocietypublishing.org/content/11/101/20140940/suppl/DC

    The 'who' and 'what' of #diabetes on Twitter

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    Social media are being increasingly used for health promotion, yet the landscape of users, messages and interactions in such fora is poorly understood. Studies of social media and diabetes have focused mostly on patients, or public agencies addressing it, but have not looked broadly at all the participants or the diversity of content they contribute. We study Twitter conversations about diabetes through the systematic analysis of 2.5 million tweets collected over 8 months and the interactions between their authors. We address three questions: (1) what themes arise in these tweets?, (2) who are the most influential users?, (3) which type of users contribute to which themes? We answer these questions using a mixed-methods approach, integrating techniques from anthropology, network science and information retrieval such as thematic coding, temporal network analysis, and community and topic detection. Diabetes-related tweets fall within broad thematic groups: health information, news, social interaction, and commercial. At the same time, humorous messages and references to popular culture appear consistently, more than any other type of tweet. We classify authors according to their temporal 'hub' and 'authority' scores. Whereas the hub landscape is diffuse and fluid over time, top authorities are highly persistent across time and comprise bloggers, advocacy groups and NGOs related to diabetes, as well as for-profit entities without specific diabetes expertise. Top authorities fall into seven interest communities as derived from their Twitter follower network. Our findings have implications for public health professionals and policy makers who seek to use social media as an engagement tool and to inform policy design.Comment: 25 pages, 11 figures, 7 tables. Supplemental spreadsheet available from http://journals.sagepub.com/doi/suppl/10.1177/2055207616688841, Digital Health, Vol 3, 201

    Relaciones de Poder en el Estado de México. Ayer y Hoy.

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    El presente trabajo pretende contribuir al conocimiento de la historia de la geografía política del actual territorio del Estado de México (hoy, con poco más de 17 millones de habitantes, la entidad federativa más poblada de la República Mexicana) desde 1825 hasta el presente; es decir, a lo largo del lapso en que ha estado vigente una estructura político-territorial a la que denominamos municipal para distinguirla de la estructura político-territorial novohispana que le precedió

    Análisis de causas y consecuencias de accidentes en el transporte de materiales peligrosos en México en el período 2016-2020

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    Se llevó a cabo un estudio de 100 accidentes ocurridos por carretera durante el transporte de materiales peligrosos (MATPEL) en México entre 2016 y 2020. Los resultados mostraron una disminución entre 2016 y 2018, y un aumento en la frecuencia de accidentes en 2019. La mayoría de los accidentes registrados ocurrieron en la región Norte (25%), seguida por las regiones Centro y Oeste (ambas con un 23%), el Sur (18%) y el Este (11%). Los tipos de accidentes más frecuentes fueron las volcaduras (56.0%), seguidas de los choques (37%) y las fallas mecánicas (7%). Las consecuencias más frecuentes derivadas de los accidentes son el derrame (43%) y la explosión (16%). Se analizaron estadísticamente las causas y consecuencias de los accidentes relacionados con la población (el número de personas muertas y heridas). Por último, se discuten los factores por los cuales se vieron afectadas las tendencias en estos accidentes.A study of 100 accidents, which occurred by road during the transport of hazardous materials (MATPEL) in Mexico between 2016 and 2020, was carried out. The results showed a decrease in the frequency of accidents from 2016 to 2018, and an increase in 2019. Most accidents recorded occurred in the North region (25%), followed by the Central and Western regions (both with 23%), the South (18%) and the East (11%). The most frequent types of accidents were rollovers (56%), followed by crashes (37%) and mechanical failures (7%). The most frequent consequences derived from accidents are release of substances (43%) and the explosion of materials (16.0 %). The causes and consequences of population-related accidents (the number of people killed and injured) were statistically analyzed. Finally, the factors by which the trends in these accidents were affected are discussed

    Utilizacion del infiltrometro con doble desague en surcos para la determinacion de las curvas de infiltracion.

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    En base a las consideraciones anteriores al propósito a esta investigación es presentar un método de determinación de la velocidad de infiltración, modificado del infiltrômetro de Surco, (boers y Millar, 1974), que analizado a través de procedimientos muy simplificados, puede proporcionar una base firme para mejorar las determinaciones de las pruebas de infiltración a nivel de predios o granjas.bitstream/item/132728/1/32523.pd

    Management of permanent teeth with necrotic pulps and open apices according to the stage of root development

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    This paper analyzed the distribution of treatments for permanent teeth with necrotic pulps and open apices according to the stage of root development. Dental records from all root canal procedures performed in permanent teeth with necrotic pulps and open apices over a period of 14 years by residents of the Speciality of Endodontics, University of Guadalajara, Mexico, were analized. Records from 206 treatments were mainly divided into the following 3 different stages according to criteria described by Cvek: stage IV (n = 79, 38.3%), stage V (n = 66, 32%) and stage III (n = 53, 25.7%). Few cases involved the initial stages of root development (stages I and II) (n = 8, 3.8%). Such teeth were submitted to four different treatments: MTA apical barrier (n = 69), Ca(OH)2 replacements (n = 34), gutta-percha (n = 67) and a plug of Ca(OH)2/gutta-percha (n = 36). The teeth with intermediate root development (Cvek stage III) showed a predilection for the MTA apical barrier and Ca(OH)2 replacement techniques (P ? 0.001). Furthermore, the stage of root development did not influence the apical extent of the root filling. The finding of permanent teeth with necrotic pulp and open apices is not exclusive to young patients with an open apex. Moreover, teeth with fragile, irregular and divergent apical morphologies, such as Cvek?s stages´ I and II, were not common and may be considered to be unusual findings. The diverse endodontic procedures were reliable regardless of the stage of root development

    In vivo morphological and antigenic characteristics of Photobacterium damselae subsp. piscicida

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    The present study was conducted to examine the morphology and antigenicity of Photobacterium damselae subsp. piscicida by culturing the bacterium in vivo in the peritoneal cavity of sea bass (Dicentrarchus labrax) within dialysis bags with either a low molecular weight (LMW) cut-off of 25 kDa or a high molecular weight (HMW) cut-off of 300 kDa. Differences were observed in the growth rate between the bacteria cultured in vivo or in vitro. Bacteria cultured in vivo were smaller and produced a capsular layer, which was more prominent in bacteria cultured in the HMW bag. Antigenicity was examined by Western blot analysis using sera from sea bass injected with live Ph. d. subsp. piscicida. The sera recognised bands at 45 and 20 kDa in bacteria cultured in vivo in the LMW bag. Bacteria cultured in vivo in the HMW bag did not express the 45 kDa band when whole cell extracts were examined, although the antigen was present in their extracellular products. In addition, these bacteria had a band at 18 kDa rather than 20 kDa. Differences in glycoprotein were also evident between bacteria cultured in vitro and in vivo. Bacteria cultured in vitro in LMW and HMW bags displayed a single 26 kDa band. Bacteria cultured in the LMW bag in vivo displayed bands at 26 and 27 kDa, while bacteria cultured in vivo in the HMW bag possessed only the 27 kDa band. These bands may represent sialic acid. The significance of the changes observed in the bacterium's structure and antigenicity when cultured in vivo is discussed

    Nitazoxanide against COVID-19 in three explorative scenarios

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    to describe the results of treating COVID-19 positive patients with nitazoxanide in three clinical settings: pregnancy/puerperium, hospitalized patients in an Internal Medicine Service and in an ambulatory setting. Methodology: This was a prospective follow-up and report of COVID-19 cases in three different situations, pregnant women, hospitalized patients receiving medical attention in an Internal Medicine Service and ambulatory patients residing in Toluca City, and Mexico City. Results: The experience with a first group of 20 women, pregnant (17) or in immediate puerperium (3) was successful in 18 cases with two unfortunate deaths. The five cases treated in an Internal Medicine service showed a positive outcome with two patients weaned from mechanical ventilation. Of the remaining 16 patients treated in an ambulatory setting, all got cured. Nitazoxanide seems to be useful against SARS-CoV-2, not only in an early intervention but also in critical condition as well as in pregnancy without undesired effects for the babies. As an adjunctive therapy budesonide was used that seems to contribute to the clinical improvement. Conclusions: Nitazoxanide could be useful against COVID-19 as a safe and available regimen to be tested in a massive way immediately

    Evaluación de parámetros productivos y reproductivos en un hato de doble propósito en Tabasco, México

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    El objetivo del estudio fue evaluar el comportamiento productivo y reproductivo de bovinos Bos taurus (BT) x Bos indicus (BI) en un sistema de doble propósito, bajo las condiciones tropicales del estado de Tabasco. Los registros se obtuvieron de la unidad de producción, UACH-URUSSE, ubicada en Teapa, Tabasco. Los años evaluados fueron 1994 a 2011, presentando información de 492 partos, y 240 lactancias completas de 130 vacas Cebú o sus cruzas (BT x BI). Los genotipos presentes en este estudio fueron las cruzas de Cebú (C) x Holstein (H): 7/8C1/8H, 3/4C1/4H, 5/8C3/8H, 1/2C1/2H, 5/8h3/8C, 11/16H5/16C y 3/4H1/4C; estos se agruparon en tres categorías 0-25%, 37.5-50% y 62.5-75% de acuerdo a la proporción de genes BT. Las variables incluyeron peso al nacimiento (PN), intervalo entre partos (IEP), producción de leche por lactancia (PLL) y duración de lactancia (DL). Los resultados indicaron que los genotipos con mayor proporción de genes BT influyó favorablemente sobre PLL (P0.05). El genotipo 62.5-75% presentó la mejor PLL (1,262.80 ± 34.80 kg) y la DL más prolongada (260.34 ± 11.20 días); comparada con los genotipos 0-25% y 37.5-50%, PLL fue 8.09 y 6.56 % mayor y con DL fue 41.72 y 33.68 días mayor, respectivamente. En conclusión, el genotipo con 62.5-75% de genes BT presentó el mejor comportamiento productivo; sin embargo, el comportamiento reproductivo fue similar en los genotipos estudiados

    Democracia en el Estado de México: fortalezas y debilidades

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    En toda interacción humana puede estar presente el poder. Por tanto, todas las formas de interacción humana son susceptibles de catalogarse como democráticas o como autoritarias (e incluso híbridas, cuando conjugan elementos democráticos y autoritarios). En la interacción democrática o bien está ausente el poder o bien éste es ejercido con tolerancia y con apego a normas preestablecidas. En la interacción autoritaria prevalece la intolerancia, la arbitrariedad y la violencia
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