22 research outputs found

    A theoretical study on the mechanism of the base-promoted decomposition of N-chloro,N-methylethanolamine

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    The first step of the base-promoted decomposition of N-chloro,N-methylethanolamine in aqueous solution (CH3N(Cl)CH2CH2OH + HO- →imine + Cl- + H2O (+ CH2O)→amine + aldehyde) is investigated at the MP2/6-31++G(d,p) computing level. Solvation is included by using both a microsolvated model, in which two explicit water molecules simulate the specific solvent effects, and a hybrid cluster-continuum model, by applying a polarized continuum on the previous results, to account for the bulk effect of the solvent. Four alternative pathways (bimolecular fragmentation, Hofmann, Zaitsev and intramolecular eliminations) are possible for the rate-limiting step of this base-promoted decomposition. These reactive processes are bimolecular asynchronous concerted reactions. The common feature of the four pathways is the proton transfer to HO- being more advanced than all other molecular events, whereas imine formation is delayed. Non-reactive cyclic arrangements involving one of the explicit water molecules are found at transition structures of Hofmann and Zaitsev eliminations, such water molecule acting both as H+ donor and acceptor. Although MP2 calculations misjudge the absolute activation Gibbs free energy values, this computational level adequately predicts the enhancement in the decomposition rate due to the presence of the -OH grou

    Impact of COVID-19 on cardiovascular testing in the United States versus the rest of the world

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    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

    4to. Congreso Internacional de Ciencia, Tecnología e Innovación para la Sociedad. Memoria académica

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    Este volumen acoge la memoria académica de la Cuarta edición del Congreso Internacional de Ciencia, Tecnología e Innovación para la Sociedad, CITIS 2017, desarrollado entre el 29 de noviembre y el 1 de diciembre de 2017 y organizado por la Universidad Politécnica Salesiana (UPS) en su sede de Guayaquil. El Congreso ofreció un espacio para la presentación, difusión e intercambio de importantes investigaciones nacionales e internacionales ante la comunidad universitaria que se dio cita en el encuentro. El uso de herramientas tecnológicas para la gestión de los trabajos de investigación como la plataforma Open Conference Systems y la web de presentación del Congreso http://citis.blog.ups.edu.ec/, hicieron de CITIS 2017 un verdadero referente entre los congresos que se desarrollaron en el país. La preocupación de nuestra Universidad, de presentar espacios que ayuden a generar nuevos y mejores cambios en la dimensión humana y social de nuestro entorno, hace que se persiga en cada edición del evento la presentación de trabajos con calidad creciente en cuanto a su producción científica. Quienes estuvimos al frente de la organización, dejamos plasmado en estas memorias académicas el intenso y prolífico trabajo de los días de realización del Congreso Internacional de Ciencia, Tecnología e Innovación para la Sociedad al alcance de todos y todas

    El secreto de Vitoria y sus silencios

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    No abstract availableRealidad: Revista de Ciencias Sociales y Humanidades No. 56, 1997: 187-203El propósito de este trabajo consiste en explorar algunos de los diferentes modos bajo los cuales el indio está siendo definido y construido en varios textos teológicos, políticos y legales en términos de su relación con instancias de poder dentro de las instituciones y prácticas discursivas del estado moderno. Este proyecto entraña una reevaluación de la obra de Vitoria a la luz de los actuales debates en tomo al conocimiento, la representación y la construcción de identidad en el estado moderno. Dentro de este marco general, se enfatizan las tensiones, contradicciones, dudas y vacilaciones de Vitoria como síntomas de los conflictos en los que se haya la moral y el pensamiento político del Renacimiento. El ensayo consiste en tres partes: en la primera se pretende mostrar cómo la obra vitoriana está fundamentada en la Teología Tomista. Vitoria está tratando de construir un "Sistema" en teología al igual que Santo Tomás lo hizo. La segunda parte describe cómo funciona el Nuevo Espacio Ontológico. La tercera esta dedicada al análisis textual, centrándose en mostrar principalmente, cómo la entidad "Indio" afecta las instancias políticas, jurídicas y teológicas en el Siglo XVI. Como conclusión se sugieren unas líneas de investigación que dirigen su esfuerzo a la reevaluación del pensamiento de Vitoria en el marco contemporáneo del debate acerca del funcionamiento del Estado moderno, así como la naturaleza de sus instituciones y sus redes de poder.Realidad: Revista de Ciencias Sociales y Humanidades No. 56, 1997: 187-20

    El jardín de Agi Morato como espacio heterotópico en Los baños de Argel de Cervantes

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    Los lugares en los que los humanos interactúan son sitios en que compiten las memorias, lugares conectados a sistemas de espacialización físicos y simbólicos. Incluso el más convencional sentido del aquí y el allí depende de una compleja red de reconocimiento simbólico que no puede divorciarse de las dinámicas de poder. Teniendo en cuenta estas ideas, me propongo examinar la (re)construcción contracultural que Cervantes hace del paisaje argelino como espacio heterotópico en Los baños de Argel..

    HIPERPARATIROIDISMO PRIMARIO Y EMBARAZO: REPORTE DE UN CASO

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    El hiperparatiroidismo primario (HPTP) se caracteriza por una hipersecreción autónoma de paratohormona (PTH), lo que provoca hipercalcemia e hipercalciuria, con afectación ósea, renal y de otras partes del organismo, en grado variable. El HPTP tiene una prevalencia de 1 en 1000 en la población general y se presenta con mayor frecuencia en mujeres que en hombres. Es infrecuente su presentación en el embarazo, y sus complicaciones derivadas de la hipercalcemia pueden afectar tanto a la madre como al feto. Presentamos el caso de una paciente de 37 años, cursando un embarazo de 10 semanas, que ingresó al servicio con los diagnósticos de nefrocalcinosis y pielonefritis aguda, a la que se diagnosticó un hiperparatiroidismo primario, cuya etiología fue un adenoma paratiroideo único.<br>Primary hyperparathyroidism (HPTP) is a disorder characterized by elevated levels of parathyroid hormone (PTH), which leads to hypercalcemia and hypercalciuria, with variable osseous, renal and other systems affectation. HPTP has a prevalence of 1:1000 in general population and is more frequent in women than men. It is very rare during pregnancy, and its complications are produced by hypercalcemia and they can affect the mother and the fetus. We present the case of a 37 year old woman, with a 10+2 weeks pregnancy that was admitted in our Hospital with nephrocalcinosis and urinary tract infection, whom was diagnosed primary hyperparathyroidism, whose etiology was a single parathyroid adenoma

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    Long-term prognosis communication preferences in early-stage relapsing-remitting multiple sclerosis.

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    Multiple sclerosis is one of the most common causes of neurological disability in young adults with major consequences for their future lives. Improving communication strategies on prognosis may help patients deal with the disease and adjust their long-term life goals. However, there is limited information on patients' preferences of long-term prognosis (LTP) communication and associated factors. The aim of this study was to describe patients' preferences and assess the factors associated with LTP communication preferences in early-stage relapsing-remitting multiple sclerosis (RRMS) patients. A multicenter, non-interventional study was conducted. Adult patients with a diagnosis of RRMS, a disease duration from first attack ≤ 3 years, and an Expanded Disability Status Scale (EDSS) score of 0-5.5 were included. The Prognosis in MS questionnaire was used to assess how much patients want to know about their LTP. Different patient-reported measures were administered to gather information on symptom severity, pain, fatigue, mood/anxiety, quality of life, stigma, illness perception, feeling of hopelessness, self-efficacy, information avoidance and coping strategies. Cognition was assessed using the Symbol Digit Modalities Test (SDMT). A multivariate logistic regression analysis was performed to assess the association between LTP information preference and demographic and clinical characteristics, as well as patients' perspectives. A total of 189 patients were included (mean age: 36.1  ±  9.4 years, 71.4% female, mean disease duration: 1.2  ±  0.8 years). Median EDSS score was 1.0 (IQR = 0.0-2.0). A proportion of 68.5% (n  =  126) of patients had never discussed LTP with their neurologists, whereas 69.2% (n = 126) reported interest in knowing it (73.5% at diagnosis). Bivariate analyses suggested that patients were significantly more likely to have higher LTP information preferences if they were male and had a lower SDMT score. Male gender and a lower SDMT score were predictors of LTP information preferences. Patients with early-stage RRMS want to discuss their LTP shortly after diagnosis. Understanding the factors involved may be useful to design individualized communication strategies
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