71 research outputs found

    Coevolutionary fuzzy modeling

    Get PDF
    This thesis presents Fuzzy CoCo, a novel approach for system design, conducive to explaining human decisions. Based on fuzzy logic and coevolutionary computation, Fuzzy CoCo is a methodology for constructing systems able to accurately predict the outcome of a human decision-making process, while providing an understandable explanation of the underlying reasoning. Fuzzy logic provides a formal framework for constructing systems exhibiting both good numeric performance (precision) and linguistic representation (interpretability). From a numeric point of view, fuzzy systems exhibit nonlinear behavior and can handle imprecise and incomplete information. Linguistically, they represent knowledge in the form of rules, a natural way for explaining decision processes. Fuzzy modeling —meaning the construction of fuzzy systems— is an arduous task, demanding the identification of many parameters. This thesis analyses the fuzzy-modeling problem and different approaches to coping with it, focusing on evolutionary fuzzy modeling —the design of fuzzy inference systems using evolutionary algorithms— which constitutes the methodological base of my approach. In order to promote this analysis the parameters of a fuzzy system are classified into four categories: logic, structural, connective, and operational. The central contribution of this work is the use of an advanced evolutionary technique —cooperative coevolution— for dealing with the simultaneous design of connective and operational parameters. Cooperative coevolutionary fuzzy modeling succeeds in overcoming several limitations exhibited by other standard evolutionary approaches: stagnation, convergence to local optima, and computational costliness. Designing interpretable systems is a prime goal of my approach, which I study thoroughly herein. Based on a set of semantic and syntactic criteria, regarding the definition of linguistic concepts and their causal connections, I propose a number of strategies for producing more interpretable fuzzy systems. These strategies are implemented in Fuzzy CoCo, resulting in a modeling methodology providing high numeric precision, while incurring as little a loss of interpretability as possible. After testing Fuzzy CoCo on a benchmark problem —Fisher's Iris data— I successfully apply the algorithm to model the decision processes involved in two breast-cancer diagnostic problems: the WBCD problem and the Catalonia mammography interpretation problem. For the WBCD problem, Fuzzy CoCo produces systems both of high performance and high interpretability, comparable (if not better) than the best systems demonstrated to date. For the Catalonia problem, an evolved high-performance system was embedded within a web-based tool —called COBRA— for aiding radiologists in mammography interpretation. Several aspects of Fuzzy CoCo are thoroughly analyzed to provide a deeper understanding of the method. These analyses show the consistency of the results. They also help derive a stepwise guide to applying Fuzzy CoCo, and a set of qualitative relationships between some of its parameters that facilitate setting up the algorithm. Finally, this work proposes and explores preliminarily two extensions to the method: Island Fuzzy CoCo and Incremental Fuzzy CoCo, which together with the original CoCo constitute a family of coevolutionary fuzzy modeling techniques. The aim of these extensions is to guide the choice of an adequate number of rules for a given problem. While Island Fuzzy CoCo performs an extended search over different problem sizes, Incremental Fuzzy CoCo bases its search power on a mechanism of incremental evolution

    Direct costs involved in providing medical attention associated with traffic accidents in BogotĂĄ

    Get PDF
    Objetivo Determinar los costos de atenciĂłn mĂ©dica generados por la accidentalidad vial en BogotĂĄ. MetodologĂ­a Estudio observacional prospectivo con datos de pacientes mayores de edad atendidos en la central de urgencias de 6 instituciones hospitalarias. Resultados El promedio del costo totalde atenciĂłn por paciente fue de 1â€Č112.000Elcostopromediodıˊadepacientehospitalizadofuede1'112.000 El costo promedio dĂ­a de paciente hospitalizado fue de 1'200.000. Pacientes con atenciĂłn ambulatoria tuvieron un costo promedio de 247.400.Elcostopromedioporaccidentesecalculoˊen247.400. El costo promedio por accidente se calculĂł en 2'333.700. Los costos mĂ©dicos por accidentes en el periodo de anĂĄlisis en BogotĂĄ fueron aproximadamente 2.301â€Č028.200.Cifrasenpesosde2011.ConclusionesLoscostosdelaatencioˊnmeˊdicadelosaccidentesdetraˊnsitoconstituyenunacargaeconoˊmicaconsiderable.Artıˊculodeinvestigacioˊn673−682ObjectiveTodeterminethecostofmedicalattentionassociatedwithtrafficaccidentsinBogotaˊ,Colombia.MethodsProspectiveobservationalstudywithdatafromadultpatientsattendedtointheemergencycentersof6hospitals.ResultsAveragetotalcostperpatientwas2.301'028.200. Cifras en pesos de 2011. Conclusiones Los costos de la atenciĂłn mĂ©dica de los accidentes de trĂĄnsito constituyen una carga econĂłmica considerable.ArtĂ­culo de investigaciĂłn673-682Objective To determine the cost of medical attention associated with traffic accidents in BogotĂĄ, Colombia. Methods Prospective observational study with data from adult patients attended to in the emergency centers of 6 hospitals. Results Average total cost per patient was 1'112.000 COP. Average daily cost of hospitalized patients was 1â€Č200.000COP.Averagecostofambulatorytreatedpatientsascendedto1'200.000 COP. Average cost of ambulatory treated patients ascended to 247.400 COP. Cost per accident calculated was 2â€Č333.700COP.Inthewholecityduringstudyperiod,totalmedicalcostswerearound2'333.700 COP. In the whole city during study period, total medical costs were around 2.301'028.200 COP. All data was expressed in 2011 Colombian pesos

    Clinical practice guideline for surgical antimicrobial prophylaxis

    Get PDF
    La infecciĂłn del sitio quirĂșrgico (ISQ) es una de las principales causas de infecciones asociadas a la atenciĂłn en salud (IAAS), con un impacto significativo en la mortalidad y morbilidad del paciente quirĂșrgico, asĂ­ como en los costos asociados a la atenciĂłn en salud. El adecuado uso de la profilaxis quirĂșrgica antimicrobiana es un aspecto fundamental en la reducciĂłn del riesgo de ISQ, dado que su utilizaciĂłn inapropiada o indiscriminada puede representar un riesgo para los pacientes y contribuir al desarrollo de resistencia a los antimicrobianos, por lo que resulta de importancia generar directrices que permitan orientar el uso adecuado de antimicrobianos en la profilaxis del paciente quirĂșrgico, con el objetivo de obtener mejores desenlaces clĂ­nicos y propender por un uso racional de antibiĂłticos. La presente guĂ­a contiene recomendaciones para profilaxis antibiĂłtica de pacientes sometidos a procedimiento quirĂșrgico, basadas en la evidencia, realizadas mediante el proceso de adaptaciĂłn de guĂ­as de prĂĄctica clĂ­nica para el contexto colombiano.Q4Pacientes sometidos a Profilaxis quirĂșrgica antimicrobianaSurgical site infection (SSI) is one of the main causes of healthcare associated infections (HAI), with a significant impact on the mortality and morbidity of the surgi-cal patient, as well as on the costs associated with health care. The adequate use of surgical antimicrobial prophylaxis being a fundamental aspect in reducing the risk of SSI, taking into account that the inappropriate or indiscriminate use of antibiotics in surgical prophylaxis may represent a risk for patients and contribute to the development of antimicrobial resistance, so it is important to generate guidelines that guide the appropriate antimicrobial prophylaxis in the surgical patient, with the aim of obtaining better clinical outcomes and promoting a rational use of antibiotics. This guide contains recommendations for antibiotic prophylaxis in patients undergoing a surgical procedure, based on evidence, carried out through the process of adapting clinical practice guidelines for the Colombian context.https://orcid.org/0000-0002-5392-7083https://orcid.org/0000-0003-2568-4667Revista Nacional - IndexadaCN

    Lo glocal y el turismo. Nuevos paradigmas de interpretaciĂłn.

    Get PDF
    El estudio del turismo se realiza desde mĂșltiples escalas y enfoques, este libro aborda muchos temas que es necesario discutir desde diversas perspectivas; es el caso de la reflexiĂłn sobre la propia disciplina y sus conceptos, asĂ­ como los asuntos especĂ­ficos referidos al impacto territorial, los tipos de turismo, las cuestiones ambientales, el tema de la pobreza, la competitividad, las polĂ­ticas pĂșblicas, el papel de las universidades, las ĂĄreas naturales protegidas, la sustentabilidad, la cultura, el desarrollo, la seguridad, todos temas centrales documentados y expuestos con originalidad y dominio del asunto. Lo multiescalar es bĂĄsico para la comprensiĂłn del sistema turĂ­stico, sistema formado de procesos globales, regionales y locales. El eje de discusiĂłn del libro es lo glocal, esa interacciĂłn entre lo nacional y local con lo global

    Evolving trends in the management of acute appendicitis during COVID-19 waves. The ACIE appy II study

    Get PDF
    Background: In 2020, ACIE Appy study showed that COVID-19 pandemic heavily affected the management of patients with acute appendicitis (AA) worldwide, with an increased rate of non-operative management (NOM) strategies and a trend toward open surgery due to concern of virus transmission by laparoscopy and controversial recommendations on this issue. The aim of this study was to survey again the same group of surgeons to assess if any difference in management attitudes of AA had occurred in the later stages of the outbreak. Methods: From August 15 to September 30, 2021, an online questionnaire was sent to all 709 participants of the ACIE Appy study. The questionnaire included questions on personal protective equipment (PPE), local policies and screening for SARS-CoV-2 infection, NOM, surgical approach and disease presentations in 2021. The results were compared with the results from the previous study. Results: A total of 476 answers were collected (response rate 67.1%). Screening policies were significatively improved with most patients screened regardless of symptoms (89.5% vs. 37.4%) with PCR and antigenic test as the preferred test (74.1% vs. 26.3%). More patients tested positive before surgery and commercial systems were the preferred ones to filter smoke plumes during laparoscopy. Laparoscopic appendicectomy was the first option in the treatment of AA, with a declined use of NOM. Conclusion: Management of AA has improved in the last waves of pandemic. Increased evidence regarding SARS-COV-2 infection along with a timely healthcare systems response has been translated into tailored attitudes and a better care for patients with AA worldwide

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

    Get PDF
    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

    GestiĂłn del conocimiento. Perspectiva multidisciplinaria. Volumen 17

    Get PDF
    El libro “GestiĂłn del Conocimiento. Perspectiva Multidisciplinaria”, Volumen 17 de la ColecciĂłn UniĂłn Global, es resultado de investigaciones. Los capĂ­tulos del libro, son resultados de investigaciones desarrolladas por sus autores. El libro es una publicaciĂłn internacional, seriada, continua, arbitrada, de acceso abierto a todas las ĂĄreas del conocimiento, orientada a contribuir con procesos de gestiĂłn del conocimiento cientĂ­fico, tecnolĂłgico y humanĂ­stico. Con esta colecciĂłn, se aspira contribuir con el cultivo, la comprensiĂłn, la recopilaciĂłn y la apropiaciĂłn social del conocimiento en cuanto a patrimonio intangible de la humanidad, con el propĂłsito de hacer aportes con la transformaciĂłn de las relaciones socioculturales que sustentan la construcciĂłn social de los saberes y su reconocimiento como bien pĂșblico

    Reducing the environmental impact of surgery on a global scale: systematic review and co-prioritization with healthcare workers in 132 countries

    Get PDF
    Abstract Background Healthcare cannot achieve net-zero carbon without addressing operating theatres. The aim of this study was to prioritize feasible interventions to reduce the environmental impact of operating theatres. Methods This study adopted a four-phase Delphi consensus co-prioritization methodology. In phase 1, a systematic review of published interventions and global consultation of perioperative healthcare professionals were used to longlist interventions. In phase 2, iterative thematic analysis consolidated comparable interventions into a shortlist. In phase 3, the shortlist was co-prioritized based on patient and clinician views on acceptability, feasibility, and safety. In phase 4, ranked lists of interventions were presented by their relevance to high-income countries and low–middle-income countries. Results In phase 1, 43 interventions were identified, which had low uptake in practice according to 3042 professionals globally. In phase 2, a shortlist of 15 intervention domains was generated. In phase 3, interventions were deemed acceptable for more than 90 per cent of patients except for reducing general anaesthesia (84 per cent) and re-sterilization of ‘single-use’ consumables (86 per cent). In phase 4, the top three shortlisted interventions for high-income countries were: introducing recycling; reducing use of anaesthetic gases; and appropriate clinical waste processing. In phase 4, the top three shortlisted interventions for low–middle-income countries were: introducing reusable surgical devices; reducing use of consumables; and reducing the use of general anaesthesia. Conclusion This is a step toward environmentally sustainable operating environments with actionable interventions applicable to both high– and low–middle–income countries
    • 

    corecore