Funciones extrañas en el análisis real: : funciones del tipo Thomae

The pathological behavior of strange functions has been of great help in the development and foundation of differential and integral calculus and, in general, of   real analysis. In addition, it is a useful source of examples and counterexamples that help understand the rigorous definitions of the basic concepts of mathematical analysis. It is for this reason that the objective of this article is to study the properties of the Thomae function, and present some generalizations to guarantee differentiability on a considerably large set of points.El comportamiento patológico de las funciones extrañas ha sido de gran ayuda en el desarrollo y fundamentación del cálculo diferencial e integral y, en general, del análisis real. Además, es una útil fuente de ejemplos y contraejemplos que ayudan a comprender las definiciones rigurosas de los conceptos básicos del análisis matemático. Es por esa razón que el objetivo de este artículo es estudiar las propiedades de la función de Thomae y presentar algunas generalizaciones para garantizar la diferenciabilidad en un conjunto considerablemente grande de puntos

FUNCIONES CLASE UNO DE BAIRE

Let , be a sequence of continuous functions defined on an interval  that converges pointwise to the function   on . It is well known that the function  could be continuous or not . However, the function   have some interesting properties. The purpose of this article is to use this idea in order to define the Baire class one functions, study their algebraic properties and prove that the uniform limit of a sequence of Baire class one functions is also a Baire class one function.  Sea , una sucesión de funciones continúas definidas en un intervalo  que converge puntualmente a la función  en . Es bien conocido que la función  puede o no ser continua en . Sin embargo, la función  posee algunas propiedades interesantes. El propósito de este artículo es usar esta idea para definir las funciones clase uno de Baire, estudiar sus propiedades algebraicas y probar que el límite uniforme de una sucesión de funciones de clases uno de Baire es también una función clase uno de Baire

CEERS Key Paper V: A triality on the nature of HST-dark galaxies

The new capabilities that JWST offers in the near- and mid-infrared (IR) are used to investigate in unprecedented detail the nature of optical/near-IR faint, mid-IR bright sources, HST-dark galaxies among them. We gather JWST data from the CEERS survey in the EGS, jointly with HST data, and analyze spatially resolved optical-to-mid-IR spectral energy distributions (SEDs) to estimate both photometric redshifts in 2 dimensions and stellar populations properties in a pixel-by-pixel basis. We select 138 galaxies with F150W-F356W>1.5 mag, F356W<27.5 mag. The nature of these sources is threefold: (1) 71% are dusty star-forming galaxies at 2<z<6 with masses 9<log M/M_sun<11 and a variety of specific SFRs (100 Gyr^-1); (2) 18% are quiescent/dormant (i.e., subject to reignition and rejuvenation) galaxies at 3<z<5, masses log M/M_sun~10 and post-starburst stellar mass-weighted ages (0.5-1 Gyr); and (3) 11% are strong young starbursts with indications of high-EW emission lines (typically, [OIII]+Hbeta) at 6<z<7 and log M/M_sun~9.5. The sample is dominated by disk-like galaxies with a remarkable compactness for XELG-z6 (effective radii smaller than 0.4 kpc). Large attenuations in SFGs, 2<A(V)<5 mag, are found within 1.5 times the effective radius, approximately 2 kpc, while QGs present A(V)~0.2 mag. Our SED-fitting technique reproduces the expected dust emission luminosities of IR-bright and sub-millimeter galaxies. This study implies high levels of star formation activity between z~20 and z~10, where virtually 100% of our galaxies had already formed 10^8 M_sun of their stellar content, 60% of them had assembled 10^9 M_sun, and 10% up to 10^10 M_sun (in situ or ex situ). (abridged)Comment: Published in CEERS ApJL Focus Issue, ApJL 946, L1

Hyperoxemia and excess oxygen use in early acute respiratory distress syndrome : Insights from the LUNG SAFE study

Publisher Copyright: © 2020 The Author(s). Copyright: Copyright 2020 Elsevier B.V., All rights reserved.Background: Concerns exist regarding the prevalence and impact of unnecessary oxygen use in patients with acute respiratory distress syndrome (ARDS). We examined this issue in patients with ARDS enrolled in the Large observational study to UNderstand the Global impact of Severe Acute respiratory FailurE (LUNG SAFE) study. Methods: In this secondary analysis of the LUNG SAFE study, we wished to determine the prevalence and the outcomes associated with hyperoxemia on day 1, sustained hyperoxemia, and excessive oxygen use in patients with early ARDS. Patients who fulfilled criteria of ARDS on day 1 and day 2 of acute hypoxemic respiratory failure were categorized based on the presence of hyperoxemia (PaO2 > 100 mmHg) on day 1, sustained (i.e., present on day 1 and day 2) hyperoxemia, or excessive oxygen use (FIO2 ≥ 0.60 during hyperoxemia). Results: Of 2005 patients that met the inclusion criteria, 131 (6.5%) were hypoxemic (PaO2 < 55 mmHg), 607 (30%) had hyperoxemia on day 1, and 250 (12%) had sustained hyperoxemia. Excess FIO2 use occurred in 400 (66%) out of 607 patients with hyperoxemia. Excess FIO2 use decreased from day 1 to day 2 of ARDS, with most hyperoxemic patients on day 2 receiving relatively low FIO2. Multivariate analyses found no independent relationship between day 1 hyperoxemia, sustained hyperoxemia, or excess FIO2 use and adverse clinical outcomes. Mortality was 42% in patients with excess FIO2 use, compared to 39% in a propensity-matched sample of normoxemic (PaO2 55-100 mmHg) patients (P = 0.47). Conclusions: Hyperoxemia and excess oxygen use are both prevalent in early ARDS but are most often non-sustained. No relationship was found between hyperoxemia or excessive oxygen use and patient outcome in this cohort. Trial registration: LUNG-SAFE is registered with ClinicalTrials.gov, NCT02010073publishersversionPeer reviewe

Multiancestry analysis of the HLA locus in Alzheimer’s and Parkinson’s diseases uncovers a shared adaptive immune response mediated by HLA-DRB1*04 subtypes

Across multiancestry groups, we analyzed Human Leukocyte Antigen (HLA) associations in over 176,000 individuals with Parkinson’s disease (PD) and Alzheimer’s disease (AD) versus controls. We demonstrate that the two diseases share the same protective association at the HLA locus. HLA-specific fine-mapping showed that hierarchical protective effects of HLA-DRB1*04 subtypes best accounted for the association, strongest with HLA-DRB1*04:04 and HLA-DRB1*04:07, and intermediary with HLA-DRB1*04:01 and HLA-DRB1*04:03. The same signal was associated with decreased neurofibrillary tangles in postmortem brains and was associated with reduced tau levels in cerebrospinal fluid and to a lower extent with increased Aβ42. Protective HLA-DRB1*04 subtypes strongly bound the aggregation-prone tau PHF6 sequence, however only when acetylated at a lysine (K311), a common posttranslational modification central to tau aggregation. An HLA-DRB1*04-mediated adaptive immune response decreases PD and AD risks, potentially by acting against tau, offering the possibility of therapeutic avenues

Paso de guardia en enfermería: Una revisión sistemática

Nursing shift handover is an obligatory and a fundamental activity to ensure continuity in the process of patient care. Objective: To describe the scientific production published between 2007-2017 regarding nursing shift handover within medical emergency services. Methodology: A systematic review was conducted on six databases. Articles with full texts written in English, Spanish, and Portuguese, and published in indexed journals were included. A critical analysis on each article was conducted using the Critical Appraisal Skills Programme spanish, and the Strengthening the Reporting of Observational Studies in Epidemiology tools. Articles were clustered in a matrix of categories. Results: From a total of 430 possible articles, 19 were included for this study -17 written in English and 2 written in Spanish. From the corresponding analysis, two categories were structured: Nursing Shift Handover Characteristics, and Process Standardization. Conclusions: Communication gaps seem to be one of the main issues to address while improving the nursing shift handover process. The patient room should be the place for the shift handover, and this process must be acknowledged by both nursing teams.A passagem de plantão em enfermagem é uma atividade fundamental para dar continuidade ao cuidado dos pacientes, realiza-se como cumprimento obrigatório de uma tarefa no trabalho laboral. Objetivo: Descrever a produção científica publicada entre 2007-2017, referente à temática de passagem de plantão de enfermagem nos serviços de urgências. Metodologia: Desenvolveu-se uma revisão sistemática em seis bases de dados, incluíram-se estudos em idiomas inglês, espanhol e português que estiveram publicados em revistas indexadas com acesso a texto completo. Realizou-se uma análise crítica de cada um dos artigos com as Ferramentas CASPe e STROBE, os resultados ordenaram-se em uma matriz que facilitou a obtenção de informação e categorias. Resultados: De um total de 430 artigos, incluíram-se à pesquisa unicamente 19, dos quais 17 estão escritos em idioma inglês e dois em espanhol. Depois da análise dos artigos selecionados estruturaram-se duas categorias: Caraterísticas da passagem de plantão e Padronização do processo. Conclusões: Os abismos na comunicação perfilam-se como um dos principais aspectos a ter em conta, para melhorar a passagem de plantão. O lugar mais recomendável para se efetuar o processo deve ser no quarto do paciente e verificado pelas duas equipes de enfermagem. Na atualidade é necessário realizar pesquisas para melhorar o nível de evidência dos estudos.El paso de guardia en enfermería es una actividad fundamental para dar continuidad al cuidado de los pacientes, se realiza como cumplimiento obligatorio de una tarea en el quehacer laboral. Objetivo: Describir la producción científica publicada entre 2007-2017, referente a la temática de paso de guardia de enfermería en los servicios de urgencias. Metodología: Se desarrolló una revisión sistemática en seis bases de datos, se incluyeron estudios en idiomas inglés, español y portugués que estuvieran publicados en revistas indexadas con acceso a texto completo. Se realizó un análisis crítico de cada uno de los artículos con las Herramientas CASPe y STROBE, los resultados se ordenaron en una matriz que facilitó la obtención de información y categorías. Resultados: De un total de 430 artículos, se incluyeron a la investigación únicamente 19, de los cuales 17 están escritos en idioma inglés y dos en español. Después del análisis de los artículos seleccionados se estructuraron dos categorías: Características del paso de guardia y Estandarización del proceso. Conclusiones: Las brechas en la comunicación se perfilan como uno de los principales aspectos a tener en cuenta, para mejorar el paso de guardia. El lugar más recomendable para que se lleve a cabo el proceso debe ser en la habitación del paciente y verificado por los dos equipos de enfermería. En la actualidad es necesario realizar investigaciones para mejorar el nivel de evidencia de los estudios

Immunocompromised patients with acute respiratory distress syndrome : Secondary analysis of the LUNG SAFE database

The aim of this study was to describe data on epidemiology, ventilatory management, and outcome of acute respiratory distress syndrome (ARDS) in immunocompromised patients. Methods: We performed a post hoc analysis on the cohort of immunocompromised patients enrolled in the Large Observational Study to Understand the Global Impact of Severe Acute Respiratory Failure (LUNG SAFE) study. The LUNG SAFE study was an international, prospective study including hypoxemic patients in 459 ICUs from 50 countries across 5 continents. Results: Of 2813 patients with ARDS, 584 (20.8%) were immunocompromised, 38.9% of whom had an unspecified cause. Pneumonia, nonpulmonary sepsis, and noncardiogenic shock were their most common risk factors for ARDS. Hospital mortality was higher in immunocompromised than in immunocompetent patients (52.4% vs 36.2%; p < 0.0001), despite similar severity of ARDS. Decisions regarding limiting life-sustaining measures were significantly more frequent in immunocompromised patients (27.1% vs 18.6%; p < 0.0001). Use of noninvasive ventilation (NIV) as first-line treatment was higher in immunocompromised patients (20.9% vs 15.9%; p = 0.0048), and immunodeficiency remained independently associated with the use of NIV after adjustment for confounders. Forty-eight percent of the patients treated with NIV were intubated, and their mortality was not different from that of the patients invasively ventilated ab initio. Conclusions: Immunosuppression is frequent in patients with ARDS, and infections are the main risk factors for ARDS in these immunocompromised patients. Their management differs from that of immunocompetent patients, particularly the greater use of NIV as first-line ventilation strategy. Compared with immunocompetent subjects, they have higher mortality regardless of ARDS severity as well as a higher frequency of limitation of life-sustaining measures. Nonetheless, nearly half of these patients survive to hospital discharge. Trial registration: ClinicalTrials.gov, NCT02010073. Registered on 12 December 2013

Immunocompromised patients with acute respiratory distress syndrome: Secondary analysis of the LUNG SAFE database

Background: The aim of this study was to describe data on epidemiology, ventilatory management, and outcome of acute respiratory distress syndrome (ARDS) in immunocompromised patients. Methods: We performed a post hoc analysis on the cohort of immunocompromised patients enrolled in the Large Observational Study to Understand the Global Impact of Severe Acute Respiratory Failure (LUNG SAFE) study. The LUNG SAFE study was an international, prospective study including hypoxemic patients in 459 ICUs from 50 countries across 5 continents. Results: Of 2813 patients with ARDS, 584 (20.8%) were immunocompromised, 38.9% of whom had an unspecified cause. Pneumonia, nonpulmonary sepsis, and noncardiogenic shock were their most common risk factors for ARDS. Hospital mortality was higher in immunocompromised than in immunocompetent patients (52.4% vs 36.2%; p &lt; 0.0001), despite similar severity of ARDS. Decisions regarding limiting life-sustaining measures were significantly more frequent in immunocompromised patients (27.1% vs 18.6%; p &lt; 0.0001). Use of noninvasive ventilation (NIV) as first-line treatment was higher in immunocompromised patients (20.9% vs 15.9%; p = 0.0048), and immunodeficiency remained independently associated with the use of NIV after adjustment for confounders. Forty-eight percent of the patients treated with NIV were intubated, and their mortality was not different from that of the patients invasively ventilated ab initio. Conclusions: Immunosuppression is frequent in patients with ARDS, and infections are the main risk factors for ARDS in these immunocompromised patients. Their management differs from that of immunocompetent patients, particularly the greater use of NIV as first-line ventilation strategy. Compared with immunocompetent subjects, they have higher mortality regardless of ARDS severity as well as a higher frequency of limitation of life-sustaining measures. Nonetheless, nearly half of these patients survive to hospital discharge. Trial registration: ClinicalTrials.gov, NCT02010073. Registered on 12 December 2013

CEERS Key Paper. IV. A Triality in the Nature of HST-dark Galaxies

The new capabilities that JWST offers in the near- and mid-infrared (IR) are used to investigate in unprecedented detail the nature of optical/near-IR-faint, mid-IR-bright sources, with HST-dark galaxies among them. We gather JWST data from the CEERS survey in the Extended Groth Strip, jointly with HST data, and analyze spatially resolved optical-to-mid-IR spectral energy distributions to estimate photometric redshifts in two dimensions and stellar population properties on a pixel-by-pixel basis for red galaxies detected by NIRCam. We select 138 galaxies with F150W − F356W > 1.5 mag and F356W 100 Gyr−1); (2) 18% are quiescent/dormant (i.e., subject to reignition/rejuvenation) galaxies (QGs) at 3 < z < 5, with logM⋆/M⊙∼10 and poststarburst mass-weighted ages (0.5–1.0 Gyr); and (3) 11% are strong young starbursts with indications of high equivalent width emission lines (typically, [O iii]+Hβ) at 6 < z < 7 (XELG-z6) and logM⋆/M⊙∼9.5 . The sample is dominated by disk-like galaxies with remarkable compactness for XELG-z6 (effective radii smaller than 0.4 kpc). Large attenuations in SFGs, 2 < A(V) < 5 mag, are found within 1.5 times the effective radius, approximately 2 kpc, while QGs present A(V) ∼ 0.2 mag. Our SED-fitting technique reproduces the expected dust emission luminosities of IR-bright and submillimeter galaxies. This study implies high levels of star formation activity between z ∼ 20 and z ∼ 10, where virtually 100% of our galaxies had already formed 108 M ⊙, 60% had assembled 109 M ⊙, and 10% up to 1010 M ⊙ (in situ or ex situ)

CEERS Key Paper. IV. A Triality in the Nature of HST-dark Galaxies

The new capabilities that JWST offers in the near- and mid-infrared (IR) are used to investigate in unprecedented detail the nature of optical/near-IR-faint, mid-IR-bright sources, with HST-dark galaxies among them. We gather JWST data from the CEERS survey in the Extended Groth Strip, jointly with HST data, and analyze spatially resolved optical-to-mid-IR spectral energy distributions to estimate photometric redshifts in two dimensions and stellar population properties on a pixel-by-pixel basis for red galaxies detected by NIRCam. We select 138 galaxies with F150W − F356W > 1.5 mag and F356W 100 Gyr−1); (2) 18% are quiescent/dormant (i.e., subject to reignition/rejuvenation) galaxies (QGs) at 3 < z < 5, with logM⋆/M⊙∼10 and poststarburst mass-weighted ages (0.5–1.0 Gyr); and (3) 11% are strong young starbursts with indications of high equivalent width emission lines (typically, [O iii]+Hβ) at 6 < z < 7 (XELG-z6) and logM⋆/M⊙∼9.5 . The sample is dominated by disk-like galaxies with remarkable compactness for XELG-z6 (effective radii smaller than 0.4 kpc). Large attenuations in SFGs, 2 < A(V) < 5 mag, are found within 1.5 times the effective radius, approximately 2 kpc, while QGs present A(V) ∼ 0.2 mag. Our SED-fitting technique reproduces the expected dust emission luminosities of IR-bright and submillimeter galaxies. This study implies high levels of star formation activity between z ∼ 20 and z ∼ 10, where virtually 100% of our galaxies had already formed 108 M ⊙, 60% had assembled 109 M ⊙, and 10% up to 1010 M ⊙ (in situ or ex situ)