Teoría de la complejidad y los sistemas de salud / Complexity theory and health systems

En la investigación en salud es todavía poco frecuente el uso de la Teoría de la Complejidad y de la Fractalidad (más aún en tópicos no relacionados directamente con la biología molecular o con la clínica). La complejidad nos propone complementar con propuestas desde nuevas perspectivas el pensamiento lineal y cuantitativo predominante todavía en la metodología de producción del conocimiento científico. El estudio de los sistemas de salud necesita un enfoque que se aparte de la linealidad, lo rígido y lo direccional, dado que los mismos son sistemas complejos en los que el todo es más que la simple suma de sus partes. La crisis global generada ante la pandemia por COVID-19 nos puso frente a la oportunidad (y a la obligación) de repensar tanto nuestra praxis cotidiana como nuestra forma de producir conocimiento (AU)

In health research, the use of the Complexity and Fractality Theory is still infrequent (even more so in topics not directly related to molecular or clinical biology). The complexity proposes us to complement with proposals from new perspectives the linear and quantitative thinking still predominant in the methodology of production of scientific knowledge. The study of health systems needs an approach that moves away from linearity, rigidity and direction, since they are complex systems in which the whole is more than the simple sum of its parts. The global crisis generated by the COVID-19 pandemic presented us with the opportunity (and the obligation) to rethink both our daily praxis and our way of producing knowledge (AU)

Social and health vulnerability of homeless people / Vulnerabilidad social y sanitaria de personas en situación de calle / Vulnerabilidade social e de saúde de pessoas em situação de rua

ABSTRACT The objective is to conduct a theoretical reflection on the social and health vulnerability of homeless people, from the perspective of complexity thinking. Study with a theoretical and reflective approach that accessed bibliographical sources of contemporary authors who seek to understand the phenomenon of homeless populations and, at the same time, attribute theoretical support from the reference of complexity, under a critical and analytical bias. Health is conceived as a subsystem of the social system that transcends any linear and punctual diagnostic perspective. Theoretical reflection on the social and health vulnerability of homeless people sparks a unique and multidimensional apprehension of the human being - a complex unit par excellence, which demands equally complex interventions.

RESUMEN El objetivo es realizar una reflexión teórica sobre la vulnerabilidad social y sanitaria de las personas en situación de calle desde la perspectiva del pensamiento de la complejidad. Se trata de un estudio con enfoque teórico y reflexivo basado en fuentes bibliográficas de autores contemporáneos que buscan comprender el fenómeno de las poblaciones sin hogar y, paralelamente, aportar sustento teórico desde el marco de la complejidad, bajo un sesgo crítico y analítico. La salud está concebida como un subsistema del medio social que trasciende cualquier perspectiva diagnóstica, lineal y puntual. La reflexión teórica sobre la vulnerabilidad social y sanitaria de las personas en situación de calle suscita una percepción singular y multidimensional del ser humano, unidad compleja por excelencia, que exige intervenciones igualmente complejas.

RESUMO Objetiva-se conduzir reflexão teórica sobre a vulnerabilidade social e de saúde de pessoas em situação de rua, na perspectiva do pensamento da complexidade. Estudo de abordagem teórico-reflexiva que acessou fontes bibliográficas de autores contemporâneos que buscam compreender o fenômeno das populações em situação de rua e, paralelamente, aprofundar a temática à luz do referencial da complexidade, sob um viés crítico e analítico. Concebe-se a saúde como subsistema do sistema social que transcende qualquer perspectiva diagnóstica linear e pontual. A reflexão teórica acerca da vulnerabilidade social e de saúde de pessoas em situação de rua acende uma apreensão singular e multidimensional de ser humano - unidade complexa por excelência, que demanda intervenções, igualmente, complexas.

A complexidade do cuidado para o controle térmico do recém-nascido prematuro / The complexity of care for the thermal control of the premature infant

RESUMO Objetivo compreender a percepção dos enfermeiros sobre a complexidade do cuidado para o controle térmico do recém-nascido prematuro. Métodos estudo qualitativo realizado com 13 enfermeiros de maternidade pública, por meio de entrevista virtual, com roteiro semiestruturado, submetido à Análise de Conteúdo e interpretado pelo suporte teórico do modelo do sistema adaptativo complexo de cuidado. Resultados os fatores presentes nos cuidados dos enfermeiros no controle térmico do recém-nascido prematuro estão relacionados à complexidade permeada por fatores ambientais como a temperatura da unidade e a distribuição das correntes de ar condicionado; fatores institucionais como a disponibilização e uso correto de tecnologias, e aos relacionados com o profissional, como atuação, treinamento e capacitação. Conclusão adequar a temperatura da unidade; melhor distribuição das correntes do ar condicionado; a disponibilidade de tecnologias; política de educação continuada no serviço; treinamentos de manuseio dos equipamentos; fiscalização e exigência de manutenção preventiva e corretiva dos aparelhos podem influenciar a redução dos eventos de instabilidade térmica do recém-nascido prematuro. Contribuições para a prática estimular a qualificação profissional, planejamento de ações intersetoriais para a estruturação tecnológica e manutenção preventiva das unidades, sistematização da assistência ao recém-nascido prematuro no controle térmico minimizando o risco de morbimortalidade neonatal por instabilidade térmica.

ABSTRACT Objective to understand the perception of nurses about the complexity of care for thermal control of the premature infant. Methods qualitative study conducted with 13 nurses from a public maternity hospital, through virtual interviews, with semi-structured script, submitted to Content Analysis and interpreted by the theoretical support of the complex adaptive care system model. Results the factors present in nurses' care in thermal control of premature infants are related to the complexity permeated by environmental factors such as the temperature of the unit and distribution of air conditioning currents; institutional factors such as the availability and correct use of technologies, and those related to the professional, such as performance, training, and qualification. Conclusion adjusting the temperature of the unit; better distribution of the air conditioning currents; availability of technologies; a policy of continued education in the service; training in handling the equipment; supervision and requirement for preventive and corrective maintenance of the devices can influence the reduction of thermal instability events in premature infants. Contributions to practice stimulating professional qualification, planning of intersectoral actions for technological structuring and preventive maintenance of the units, systematization of assistance to premature infants in thermal control minimizing risk of neonatal morbimortality due to thermal instability.

Proposal of a non-linear model to adjust in vitro gas production at different incubation times

This work aims to propose a new model named Gompertz-Von Bertalanffy bicompartmental (GVB), a combination of the models Gompertz and Von Bertalanffy. The GVB models is applied to fit the kinetic curve of cumulative gas production (CGP) of four foods (SS ­ sunflower silage; CS ­ corn silage; and the mixtures 340SS ­ 660 gkg-1 of corn silage and 340 gkg-1 of sunflower silage; and 660SS ­ 340 gkg-1 of corn silage and 660 gkg-1 of sunflower silage). The GVB fit is compared to models Logistic-Von Bertalanffy bicompartmental (LVB) and bicompartmental logistic (BL). All the process studied employed the semi-automatic "in vitro" technique of producing gases used in ruminant nutrition. The gas production readout was performed at times 2, 4, 6, 8, 10, 12, 15, 19, 24, 30, 48, 72, and 96 h. The data generated were used to estimate the models' parameters by the least squared method with the iterative Gauss-Newton process. The data fit quality of the models was verified using the adjusted coefficient of determination criterion (), mean residual square (MRS), Akaike information criterion (AIC), and mean absolute deviation (MAD). Among the analyzed models, the LVB model presented the best quality of fit evaluators for CS. In contrast, the GVB model showed better quality of fit to describe CGP over time for 340SS, 660SS, and SS, presenting the highest values of () and the lowest values of MSR, AIC, and MAD.

Resultados en psicoterapia individual de adultos desde la perspectiva de los Sistemas Dinámicos: una revisión sistemática / Adult individual psychotherapy results from the Dynamic Systems perspective: a systematic review

Resumen: Existe un variado número de investigaciones que emplea nociones de la perspectiva de sistemas dinámicos (SD) para describir procesos de cambio en psicoterapia, conceptualizándolo como un sistema no lineal autoorganizado que presenta procesos emergentes y variaciones estructurales. Se realizó una revisión sistemática de la investigación en psicoterapia individual con pacientes adultos abordada desde esta perspectiva. La revisión se sustentó en la metodología PRISMA rastreando los principales conceptos de la perspectiva SD aplicados a la psicoterapia individual de adultos (entre 1997 y 2019), en los idiomas inglés y español, utilizando las bases de datos electrónicas PsycINFO y ProQuest. La selección final incluyó 34 estudios, tanto estudios de caso como estudios naturalistas, que abordaron diferentes variables de proceso y resultado de la psicoterapia. Los resultados resaltan la forma en que dichos conceptos ayudan a comprender el cambio de los pacientes como un proceso no lineal, destacando sus características de autoorganización, transiciones desde estados que generan sufrimiento psicológico a estados más saludables, y la formación de patrones emergentes en diferentes etapas de la psicoterapia. Se discuten algunos aspectos derivados (p.e. rol de la alianza, y de las intervenciones clínicas) que pueden ser abordados en el trabajo terapéutico.

Abstract: There is a diverse body of research that utilizes notions of the dynamical systems (DS) perspective to describe change processes in psychotherapy, understanding it as a non-linear self-organized system that presents emergent processes and structural variations. A systematic review of research in individual psychotherapy with adult patients addressed from this perspective has been carried out. The review was carried out supported by the PRISMA methodology tracking the main concepts of the DS perspective applied to individual psychotherapy of adults (between 1997 and 2019), in English and Spanish, using the electronic databases PsycINFO and ProQuest. The final selection included 34 studies, both case studies and naturalistic studies, covering different process and outcome variables of psychotherapy. The results highlight how such concepts help to understand patients' change as a nonlinear process, emphasizing its self-organizing characteristics, transitions from states that generate psychological distress to healthier states, and the formation of emergent patterns at different stages of psychotherapy. Some related aspects (e.g. role of the alliance, and of clinical interventions) that can be considered in the therapeutic work are discussed.

Study of nonlinear viscoelastic mechanical properties of degenerated intervertebral discs / Estudio de las propiedades mecánicas viscoelásticas no lineales de discos intervertebrales degenerados

SUMMARY: Biomechanical factors are important factors in inducing intervertebral disc degeneration, in this paper, the nonlinear viscoelastic mechanical properties of degenerated intervertebral discs were analyzed experimentally. Firstly, the loading and unloading curves of intervertebral discs before and after degeneration at different strain rates were compared to analyze the changes of their apparent viscoelastic mechanical properties; The internal stress/strain distribution of the disc before and after degeneration was then tested by combining digital image technology and fiber grating technology. The results show that the intervertebral disc is strain-rate- dependent whether before or after degeneration; The modulus of elasticity and peak stress of the degenerated disc are significantly reduced, with the modulus of elasticity dropping to 50 % of the normal value and the peak stress decreasing by about 55 %; Degeneration will not change the distribution of the overall internal displacement of the intervertebral disc, but has a greater impact on the superficial and middle AF; The stress in the center of the nucleus pulposus decreases, and the stress in the outer AF increases after degeneration. Degeneration has a great impact on the nonlinear viscoelastic mechanical properties of intervertebral disc, which has reference value for the mechanism, treatment and prevention of clinical degenerative diseases.

RESUMEN: Los factores biomecánicos son importantes en la inducción de la degeneración del disco intervertebral. En este estudio se analizaron experimentalmente las propiedades mecánicas viscoelásticas no lineales de los discos intervertebrales degenerados. En primer lugar se compararon las curvas de carga y descarga de los discos intervertebrales, antes y después de la degeneración, a diferentes velocidades de deformación para analizar los cambios aparentes de sus propiedades mecánicas viscoelásticas. La distribución interna de tensión/deformación del disco antes y después de la degeneración se probó luego combinando tecnología de imagen digital y tecnología de rejilla de fibra. Los resultados mostraron que el disco intervertebral depende de la velocidad de deformación antes o después de la degeneración; El módulo de elasticidad y la tensión máxima del disco degenerado se reducen significativamente, cayendo el módulo de elasticidad al 50 % del valor normal y la tensión máxima disminuyendo en aproximadamente un 55 %; La degeneración no cambiará la distribución del desplazamiento interno general del disco intervertebral, pero tiene un mayor impacto en la FA superficial y media; El estrés en el centro del núcleo pulposo disminuye y el estrés en el FA externo aumenta después de la degeneración. La degeneración tiene un gran impacto en las propiedades mecánicas viscoelásticas no lineales del disco intervertebral, que tiene valor de referencia para el mecanismo, tratamiento y prevención de enfermedades clínicas degenerativas.

Reflections on the fundamental nature of homeopathic potencies: Plasma, Langmuir Adsorption and Vitalism

There is a pressing need to develop methods and approaches that will identify the fundamental nature of homeopathic potencies. Aims: To bring together recent basic research on potencies, especially that using solvatochromic dyes, and to supplement these results with reliable observations made by Hahnemann and his contemporaries from the very beginnings of homeopathy, together with a detailed examination of the process of trituration and succussion coupled to dilution, in order to significantly limit the number of possible explanations as to the identity of potencies. Methodology: A mixture of lab based and literature studies such that as far as possible all verified and substantiated observations about homeopathic potencies have been examined. Results and Discussion: An understanding of the fundamental nature of homeopathic potencies that includes all known and accepted observations (in vitro, in vivoand clinical) is not realistic without embracing hypotheses involving the emergent properties of complex systems and in particular, vitalistic concepts. Using a vitalistic model it is possible to explain a wide range of seemingly unrelated phenomena -such as the polarising effect of potencies on solvatochromic dyes, the ability to use a range of materials such as water, lactose and cellulose as carriers of potencies, the administering of potencies by olfaction, the antidoting effect of camphor on potency action, the non-linear dependence of potency strength on volume as well as succussion level, the oscillatory behaviour of potencies and experimenter/observer/practitioner effects. Conclusion: A hypothesis in which homeopathic potencies can be seen as self-actuating and autonomous plasma generated by trituration and/or succussion and carried according to Langmuir adsorption models fits the known observations about potencies.

Leadership in Nursing and Health Care in the Light of Complexity Thinking / Liderazgo de Enfermería y salud a la luz del pensamiento de la complejidad / Liderança em Enfermagem e saúde à luz do pensamento da complexidade

ABSTRACT This study aims to perform a critical-reflective analysis of leadership in nursing and health in the light of complexity thinking. This is a theoretical-reflexive essay based on the framework of complexity thinking. A parallel is conceived between traditional Cartesian leadership, outlined from a defined linear hierarchical structure, and leadership from a systemic-complex perspective. A schematic structure is demonstrated between the pyramidal conception and systemic-complex leadership, leading to circularity, complementarity, interdependence, and interactivity. Leadership's central role in nursing and health care is reaffirmed based on interactive, dialogic, and interdependent movements. The theoretical reflection calls for evolutionary and shared leadership in nursing and health, determined by the quality of interactions between members and different systems, in order to respond to the complexity of health phenomena quickly, effectively, and sustainably.

RESUMEN El objetivo es realizar un análisis crítico-reflexivo del liderazgo de enfermería y salud a la luz del pensamiento de la complejidad. Este es un ensayo teórico-reflexivo basado en el referencial del pensamiento de la complejidad. Se establece un paralelismo entre el liderazgo tradicional cartesiano, esbozado desde una estructura jerárquica lineal definida y el liderazgo, desde una perspectiva sistémica-compleja. Se demuestra una estructura esquemática entre la concepción piramidal y el liderazgo sistémico-complejo que conduce a la circularidad, la complementariedad, la interdependencia y la interactividad. Se reafirma el papel central del liderazgo en la enfermería y la salud, desde movimientos interactivos, dialógicos e interdependientes. La reflexión teórica reclama un liderazgo evolutivo y compartido en la enfermería y la salud, determinado por la calidad de las interacciones entre los miembros y los diferentes sistemas para responder a la complejidad de los fenómenos sanitarios de forma rápida, eficaz y sostenible.

RESUMO Objetiva-se realizar análise crítico-reflexiva sobre a liderança em enfermagem e saúde, à luz do pensamento da complexidade. Ensaio teórico-reflexivo alicerçado no referencial do pensamento da complexidade. Concebe-se um paralelo entre a liderança tradicional cartesiana, esboçada a partir de uma estrutura hierárquica linear definida e a liderança na perspectiva sistêmico-complexa. Demonstra-se uma estrutura esquemática entre a concepção piramidal e a liderança sistêmico-complexa que conduz à circularidade, complementaridade, interdependência e interatividade. Reafirma-se o papel central da liderança em enfermagem e saúde, a partir de movimentos interativos, dialógicos e interdependentes. A reflexão teórica convoca à liderança evolutiva e compartilhada em enfermagem e saúde, determinada pela qualidade das interações entre os membros e os diferentes sistemas, no sentido de responder à complexidade dos fenômenos de saúde de forma rápida, eficaz e sustentável.

Nursing care as a systemic and entrepreneurial phenomenon / El cuidado de enfermería como fenómeno sistémico y emprendedor / O cuidado de enfermagem como fenômeno sistêmico e empreendedor

ABSTRACT The objective is to produce a critical-reflexivity analysis of nursing care, from the perspective of complexity thinking and social entrepreneurship. Theoretical-reflective study, supported by the framework of complexity thinking and social entrepreneurship. The main characteristics that lead and support nursing care are analyzed from a systemic-entrepreneurial perspective. A parallel is conceived between vertical care, design from a hierarchical structure and nursing care in the systemic-entrepreneurial perspective, which leads to singularity, originality, circularity, complementarity and interactivity. The centrality of nursing care is reaffirmed as a tangible social good or not. Theoretical reflection on nursing care as a systemic and entrepreneurial phenomenon raises a unique and multidimensional perception of the human being/user, health, the nursing work process, in order to achieve an increasingly agile, dynamic, circular, complementary and interdependent care.

RESUMEN Este estudio pretende realizar un análisis crítico-reflexivo de los cuidados de enfermería desde la perspectiva del pensamiento de la complejidad y del emprendimiento social. Se trata de un estudio teórico-reflexivo, apoyado en el marco del pensamiento de la complejidad y del emprendimiento social. Se analizan las principales características que conducen y sostienen los cuidados de enfermería desde una perspectiva sistémico-emprendedora. Se establece un paralelismo entre los cuidados verticales, perfilados desde una estructura jerárquica, y los cuidados de enfermería, desde una perspectiva sistémico-emprendedora, que conduce a la singularidad, la originalidad, la circularidad, la complementariedad y la interactividad. Se reafirma la centralidad de los cuidados de enfermería como bien social tangible o intangible. La reflexión teórica sobre el cuidado enfermero como fenómeno sistémico y emprendedor plantea una percepción singular y multidimensional del ser humano/usuario, de la salud y del proceso de trabajo enfermero, para lograr un cuidado cada vez más ágil, dinámico, circular, complementario e interdependiente.

RESUMO Objetiva-se produzir análise crítico-reflexiva sobre o cuidado de enfermagem, na perspectiva teórico-reflexiva do pensamento da complexidade e do empreendedorismo social. Observa-se as principais características que conduzem e sustentam o cuidado de enfermagem na perspectiva sistêmico-empreendedora. Concebe-se um paralelo entre o cuidado vertical, esboçado a partir de uma estrutura hierárquica, e o cuidado de enfermagem na perspectiva sistêmico-empreendedora, que conduz à singularidade, à originalidade, à circularidade, à complementaridade e à interatividade. Reafirma-se a centralidade do cuidado de enfermagem como bem-social tangível ou não. A reflexão teórica acerca do cuidado de enfermagem como fenômeno sistêmico e empreendedor suscita uma percepção singular e multidimensional de ser humano/usuário, saúde, processo de trabalho da enfermagem, no intuito de alcançar um cuidado cada vez mais ágil, dinâmico, circular, complementar e interdependente.

Research progress and application of transfer entropy algorithm / 生物医学工程学杂志

In recent years, exploring the physiological and pathological mechanisms of brain functional integration from the neural network level has become one of the focuses of neuroscience research. Due to the non-stationary and nonlinear characteristics of neural signals, its linear characteristics are not sufficient to fully explain the potential neurophysiological activity mechanism in the implementation of complex brain functions. In order to overcome the limitation that the linear algorithm cannot effectively analyze the nonlinear characteristics of signals, researchers proposed the transfer entropy (TE) algorithm. In recent years, with the introduction of the concept of brain functional network, TE has been continuously optimized as a powerful tool for nonlinear time series multivariate analysis. This paper first introduces the principle of TE algorithm and the research progress of related improved algorithms, discusses and compares their respective characteristics, and then summarizes the application of TE algorithm in the field of electrophysiological signal analysis. Finally, combined with the research progress in recent years, the existing problems of TE are discussed, and the future development direction is prospected.

Cultura del caos / Chaos Culture

La Teoría del Caos, considerada la tercera revolución de la física, se ha convertido en un método científico para abordar sistemas complejos que no pueden ser explicados por los recursos tradicionales de la ciencia. Su campo de aplicación es cada vez más amplio, porque el pensamiento complejo ha ofrecido solución a numerosos sistemas en la naturaleza, la biología y muy diversas esferas de la vida. El objetivo de este trabajo es ofrecer una panorámica general sobre el tema, desde una postura no estrictamente matemática. Se realizó una revisión en la literatura y se expone el conocimiento sedimentado en el tiempo, por los estudiosos y expertos en la materia. Se ofrece una visión general de la Teoría del Caos, las condiciones para su surgimiento, así como sus aspectos y propiedades generales expresadas en sus dos dimensiones: tiempo (sistemas dinámicos) y espacio (fractales). Se hacen explícitos en cada caso, los conceptos y definiciones necesarias para entender y hablar de Caos. En un segundo artículo se expondrán las principales aplicaciones de esta teoría en la medicina y en particular en el campo de las neurociencias. Para los profesionales del sector salud, resulta un reto necesario familiarizarse con este nuevo enfoque, entender su esencia, principios y conceptos, para adquirir una cultura del Caos(AU)

Chaos Theory, considered the third revolution in physics, has become a scientific method to address complex systems that cannot be explained by the traditional resources of science. Its field of application is increasingly wide, because complex thinking has offered solutions to numerous systems in nature, biology and very diverse spheres of life. The objective of this work is to offer a general overview of the subject, from a non-strictly mathematical position. A literature review was carried out and the knowledge settled over time, by scholars and experts in the field, is exposed. An overview of Chaos Theory is offered, the conditions for its emergence, as well as its aspects and general properties expressed in its two dimensions: time (dynamic systems) and space (fractals). The concepts and definitions necessary to understand and speak of Chaos are made explicit in each case. In a second article, the main applications of this theory in medicine and in particular in the field of neurosciences will be exposed. For professionals in the health sector, it is a necessary challenge to become familiar with this new approach, understand its essence, principles and concepts, to acquire a culture of Chaos(AU)

Dinámica no lineal de la regulación autonómica cardiovascular durante la prueba del peso sostenido en pacientes con diabetes mellitus tipo 2 / Nonlinear dynamics of cardiovascular autonomic regulation during the sustained weight test in patients with type 2 diabetes mellitus

Resumen Introducción: La dinámica no lineal de la regulación autonómica cardiovascular a partir de la variabilidad de la frecuencia cardiaca no ha sido previamente estudiada en pacientes con diabetes mellitus tipo 2 mediante la prueba del peso sostenido como inductor de hiperreactividad cardiovascular. Objetivo: Determinar las variaciones en la dinámica no lineal de la regulación autonómica cardiovascular durante la prueba del peso sostenido en pacientes con diabetes mellitus tipo 2. Método: Estudio cuasiexperimental, antes-después, con grupo control, realizado en junio-agosto de 2018 en la Facultad No. 1 de Medicina de Santiago de Cuba. Se trabajó con 15 pacientes que padecían diabetes mellitus tipo 2 sin otra enfermedad asociada y 15 sujetos sanos, a quienes se les aplicó la prueba del peso sostenido. Resultados: En los pacientes con diabetes mellitus, al realizar la prueba del peso sostenido se produjo un aumento significativo en la presión arterial sistólica, diastólica y media, y en la frecuencia cardiaca. En la entropía muestral, parámetro que evalúa la adaptabilidad de los sistemas, se produjo una disminución significativa (2.28 ± 0.33 vs. 1.83 ± 0.47 ms; p = 0.003143). El valor del estadístico C de la entropía muestral en estado basal quedó establecido en 0.973, siendo la variable con mayor capacidad predictiva. Conclusiones: Durante la prueba del peso sostenido en los pacientes con diabetes mellitus tipo 2 se produjo una disminución de la complejidad de la regulación autonómica cardiovascular; la entropía muestral basal constituyó el indicador de mayor eficacia en la identificación de alteraciones autonómicas cardiovasculares.

Abstract Introduction: The analysis of non-linear dynamics of cardiovascular autonomic regulation based on heart rate variability has not been previously studied in patients with type 2 diabetes mellitus using the sustained weight test as an inducer of cardiovascular hyperreactivity. Objective: To determine the variations in the non-linear dynamics of cardiovascular autonomic regulation during the sustained weight test in patients with type 2 diabetes mellitus. Method: A quasi-experimental, before-after study with a control group, from June-August 2018, at the No. 1 School of Medicine in Santiago de Cuba. We worked with 15 patients suffering from type 2 diabetes mellitus without other associated disease and 15 healthy subjects, to whom the sustained weight test was applied. Results: In patients with diabetes mellitus, when performing the sustained weight test, there was a significant increase in the hemodynamic parameters TAS, TAD, TAM and FC. In the sample entropy, a parameter that evaluates the adaptability of the systems, there is a significant decrease (2.28 ± 0.33 vs. 1.83 ± 0.47 ms; p = 0.003143). The value of the C statistic of the sample entropy at baseline was established at 0.973, being the variable with the highest predictive capacity. Conclusions: In patients with type 2 diabetes mellitus during the sustained weight test, there was a decrease in the complexity of cardiovascular autonomic regulation, the basal sample entropy was the indicator of greater efficacy in the identification of cardiovascular autonomic alterations.

Linear and Nonlinear Heart Rate Variability Analysis in Gonadal Dysgenesis (Swyer Syndrome): A Case Report

Abstract Swyer syndrome is one of the disorders of sexual differentiation. Previous studies have demonstrated increased sympathetic activity with heart rate variability (HRV) analysis with decreasing estradiol levels. One patient presented a pure 46, XY gonadal dysgenesis with female phenotype. Cardiac autonomic modulation was assessed through HRV analysis while at rest. This research analyzed linear and nonlinear indexes. HRV analysis showed reduced parasympathetic and global modulation with an apparent increase in sympathetic tone and a loss of HR fractal dynamics toward correlated behavior, characterized by low entropy and high determinism of time series.

Confirmación diagnóstica de la metodología diseñada para evaluar los registros Holter durante 18 horas mediante la entropía proporcional / Diagnostic confirmation of the methodology designed to evaluate the Holter registers for 18 hours through proportional entropy

Resumen Introducción: Los sistemas dinámicos, la entropía y la probabilidad han contribuido de forma significativa al desarrollo de nuevas metodologías que caracterizan al grado de complejidad de la dinámica cardíaca. Objetivo: Confirmar la aplicabilidad clínica de la metodología fundamentada en la teoría de los sistemas dinámicos, la probabilidad y la entropía para evaluar la dinámica cardíaca durante 18 horas. Material y métodos: Se tomaron 570 registros Holter normales en diferentes enfermedades. Para cada uno se construyó un atractor en un mapa de retardo y se evaluó la probabilidad de ocupación de pares ordenados de frecuencias cardíacas durante 18 horas, así como la entropía y sus proporciones. Se compararon las medidas obtenidas con los valores de normalidad y enfermedad establecidos previamente para obtener el diagnóstico matemático de cada Holter. Las conclusiones del Holter se revelaron luego de aplicar la metodología fisicomatemática para calcular sensibilidad, especificidad y coeficiente kappa respecto de la norma de referencia clínica. Resultados: Con las proporciones de la entropía de los atractores se diferenciaron dinámicas cardíacas agudas, crónicas, normales y la evolución entre estos estados con resultados de sensibilidad y especificidad del 100% con una concordancia entre la norma de referencia y el diagnóstico fisicomatemático evaluado con el coeficiente kappa de 1. Conclusiones: Este estudio confirma que la metodología aplicada logra diagnosticar objetivamente la dinámica cardíaca, ya que establece predicciones de estados de normalidad o del nivel de agravamiento de la dinámica, y evidencia la aplicabilidad de esta metodología, lo cual sugiere su potencial uso en el contexto clínico.

Abstract Introduction: Dynamic systems, entropy and probability have contributed significantly in the development of new methodologies that characterize the degree of complexity of cardiac dynamics. Objective: To confirm the clinical applicability of the methodology based on the theory of dynamic systems, probability and entropy to evaluate cardiac dynamics during 18 hours. Material and methods: 570 normal Holter records with different pathologies were taken. For each one an attractor was built on the delay map and the probability of occupation of ordered pairs of heart rates during 18 hours was evaluated, as well as the entropy and its proportions. The measurements obtained were compared with the values of normality and illness established previously to obtain the mathematical diagnosis of each Holter. The conclusions of the Holter were unblinded after having applied the physical-mathematical methodology to calculate sensitivity, specificity and Kappa coefficient with respect to the Gold-Standard. Results: With the proportions of the entropy of the attractors, acute, chronic, normal, and evolution cardiac dynamics were differentiated between these states. the application of the methodology showed a sensitivity and specificity of 100 %. The agreement between the Gold-Standard and the physical-mathematical diagnosis evaluated with the kappa coefficient was 1. Conclusions: This study confirms that the applied methodology manages to objectively diagnose cardiac dynamics, establishing predictions of normality states or the level of aggravation of the dynamics, evidencing the applicability of this methodology, suggesting its potential use in the clinical context.

Impact of chronic obstructive pulmonary disease on linear and nonlinear dynamics of heart rate variability in patients with heart failure

The objective of this study was to investigate the impact of chronic obstructive pulmonary disease (COPD)-heart failure (HF) coexistence on linear and nonlinear dynamics of heart rate variability (HRV). Forty-one patients (14 with COPD-HF and 27 HF) were enrolled and underwent pulmonary function and echocardiography evaluation to confirm the clinical diagnosis. Heart rate (HR) and R-R intervals (iRR) were collected during active postural maneuver (APM) [supine (10 min) to orthostasis (10 min)], respiratory sinus arrhythmia maneuver (RSA-M) (4 min), and analysis of frequency domain, time domain, and nonlinear HRV. We found expected autonomic response during orthostatic changes with reduction of mean iRR, root mean square of successive differences between heart beats (RMSSD), RR tri index, and high-frequency [HF (nu)] and an increased mean HR, low-frequency [LF (nu)], and LF/HF (nu) compared with supine only in HF patients (P<0.05). Patients with COPD-HF coexistence did not respond to postural change. In addition, in the orthostatic position, higher HF nu and lower LF nu and LF/HF (nu) were observed in COPD-HF compared with HF patients. HF patients showed an opposite response during RSA-M, with increased sympathetic modulation (LF nu) and reduced parasympathetic modulation (HF nu) (P<0.05) compared with COPD-HF patients. COPD-HF directly influenced cardiac autonomic modulation during active postural change and controlled breathing, demonstrating an autonomic imbalance during sympathetic and parasympathetic maneuvers compared with isolated HF.

Nursing Now and Nursing in the future: the experience of the unexpected irruptions / Nursing Now and Nursing in the future: a experiência das irrupções do inesperado / Nursing Now and Nursing in the future: experiencia de las irrupciones de lo inesperado

Objective: to carry out a theoretical reflection on the Nursing Now Campaign and the experience of the unexpected irruptions facing the pandemic period. Method: a theoretical-reflective study, supported by the theoretical framework of complexity thinking. It aims at understanding the dialogic between the notions of order, disorder and organization, which translate the transition from simplification to complexity of the pandemic phenomenon and its relation to the theme of Nursing Now and Nursing in the future. Results: the universe of phenomena is simultaneously composed of order, disorder and organization. Reasserting the central role of Nursing in the health team, facing the irruptions and uncertainties caused by the current pandemic, implies the ability to dialog with disorder and raise a new and more complex global (re)organization of the being and doing Nursing. Conclusion: in addition to answers, theoretical reflection raises new questions and irruptions. The inseparability between the notions of order and disorder in the evolutionary dynamics of the Nursing system is conceived and the promotion of even more complex levels of organization, management and Nursing assistance to achieve universal access to health is advocated.

Objetivo: realizar reflexão teórica acerca da Campanha Nursing Now e a experiência das irrupções do inesperado face ao período pandêmico. Método: estudo teórico-reflexivo, apoiado no referencial teórico do pensamento da complexidade. Visa-se à compreensão da dialógica entre as noções de ordem, de desordem e de organização, as quais traduzem a passagem da simplificação à complexidade do fenômeno da pandemia e sua relação com a temática Nursing Now and Nursing in the future. Resultados: o universo dos fenômenos é tecido, simultaneamente, de ordem, de desordem e de organização. Reafirmar o papel central da Enfermagem na equipe de saúde, face às irrupções e incertezas provocadas pela pandemia em curso, implica capacidade de dialogar com a desordem e suscitar uma nova e mais complexa (re)organização global do ser e do fazer Enfermagem. Conclusão: a reflexão teórica suscita, além de respostas, novos questionamentos e novas irrupções. Concebe-se a inseparabilidade entre as noções de ordem e de desordem na dinâmica evolutiva do sistema de Enfermagem e defende-se a promoção de níveis de organização, gestão e assistência de Enfermagem ainda mais complexos para o alcance do acesso universal à saúde.

Objetivo: realizar una reflexión teórica sobre la Campaña Nursing Now y la experiencia de las irrupciones de lo inesperado ante el período pandémico. Método: estudio teórico-reflexivo, basado en el marco teórico del pensamiento complejo. Tiene como objetivo comprender la dialógica entre las nociones de orden, desorden y organización, que traducen la transición de la simplificación a la complejidad del fenómeno pandémico y su relación con el tema Nursing Now and Nursing in the future. Resultados: el universo de los fenómenos se entreteje, simultáneamente, de orden, desorden y organización. Reafirmar el papel central de la Enfermería en el equipo de salud, ante las irrupciones e incertidumbres provocadas por la pandemia actual, implica la capacidad de dialogar con el desorden y propiciar una nueva y más compleja (re)organización global del ser y hacer Enfermería. Conclusión: la reflexión teórica plantea, además de respuestas, nuevas interrogantes y nuevas irrupciones. Se concibe la inseparabilidad entre las nociones de orden y desorden en la dinámica evolutiva del sistema de Enfermería y se aboga por la promoción de niveles aún más complejos de organización, gestión y asistencia de Enfermería para lograr el acceso universal a la salud.

The role of absolute humidity in respiratory mortality in Guangzhou, a hot and wet city of South China

BACKGROUND@#For the reason that many studies have been inconclusive on the effect of humidity on respiratory disease, we examined the association between absolute humidity and respiratory disease mortality and quantified the mortality burden due to non-optimal absolute humidity in Guangzhou, China.@*METHODS@#Daily respiratory disease mortality including total 42,440 deaths from 1 February 2013 to 31 December 2018 and meteorological data of the same period in Guangzhou City were collected. The distributed lag non-linear model was used to determine the optimal absolute humidity of death and discuss their non-linear lagged effects. Attributable fraction and population attributable mortality were calculated based on the optimal absolute humidity, defined as the minimum mortality absolute humidity.@*RESULTS@#The association between absolute humidity and total respiratory disease mortality showed an M-shaped non-linear curve. In total, 21.57% (95% CI 14.20 ~ 27.75%) of respiratory disease mortality (9154 deaths) was attributable to non-optimum absolute humidity. The attributable fractions due to high absolute humidity were 13.49% (95% CI 9.56 ~ 16.98%), while mortality burden of low absolute humidity were 8.08% (95% CI 0.89 ~ 13.93%), respectively. Extreme dry and moist absolute humidity accounted for total respiratory disease mortality fraction of 0.87% (95% CI - 0.09 ~ 1.58%) and 0.91% (95% CI 0.25 ~ 1.39%), respectively. There was no significant gender and age difference in the burden of attributable risk due to absolute humidity.@*CONCLUSIONS@#Our study showed that both high and low absolute humidity are responsible for considerable respiratory disease mortality burden, the component attributed to the high absolute humidity effect is greater. Our results may have important implications for the development of public health measures to reduce respiratory disease mortality.

Effects of Temperature on Outpatient Visits for Urticaria among Lanzhou Residents Based on Distributed Lag Non-linear Model / 中国医学科学院学报

Objective To evaluate the influence of temperature on the outpatient visits for urticaria in Lanzhou City and its hysteresis and to find out the sensitive populations by sex and age stratification.Methods We collected the urticaria outpatient data in three grade A class three hospitals as well as the meteorological data and air pollutant data in Lanzhou from January 2011 to December 2017.The distributed lag non-linear model(DLNM)was employed to analyze the influence of daily mean temperature on the outpatient visits for urticaria.Stratification analysis was performed for different age groups(0-14,15-59,≥60 years)and different sex populations.Results Temperature had a non-linear relationship with the outpatient visits for urticaria,and there existed hysteresis.During the research period,the average daily outpatient visits for urticaria at the three hospitals in Lanzhou was 25,ranging from 1 to 76.With the rise in the daily mean temperature within 0-10 ℃,the risk of outpatient visits for urticaria first increased and then decreased.When the daily mean temperature was 2 ℃,hysteresis occurred on the 18th day,and the relative risk(

Realization of non-invasive blood glucose detector based on nonlinear auto regressive model and dual-wavelength / 生物医学工程学杂志

The use of non-invasive blood glucose detection techniques can help diabetic patients to alleviate the pain of intrusive detection, reduce the cost of detection, and achieve real-time monitoring and effective control of blood glucose. Given the existing limitations of the minimally invasive or invasive blood glucose detection methods, such as low detection accuracy, high cost and complex operation, and the laser source's wavelength and cost, this paper, based on the non-invasive blood glucose detector developed by the research group, designs a non-invasive blood glucose detection method. It is founded on dual-wavelength near-infrared light diffuse reflection by using the 1 550 nm near-infrared light as measuring light to collect blood glucose information and the 1 310 nm near-infrared light as reference light to remove the effects of water molecules in the blood. Fourteen volunteers were recruited for

Diferencias inter e intra-hemisféricas de dinámicas no lineales en las señales de electroencefalograma durante la resolución de una prueba de atención / Inter- and intra-hemispheric differences of non-linear dynamics in electroencephalogram signals during the execution of an attention test

Resumen Introducción. La actividad cerebral, teniendo en cuenta su dinámica aperiódica, puede ser estudiada mediante funciones no lineales o sistemas caóticos. Objetivo. Estudiar las diferencias inter e intra-hemisféricas de la relación orden/caos en la actividad cerebral de la onda beta en estudiantes universitarios durante la resolución de un test de atención. Materiales y métodos. La muestra estuvo compuesta por 10 estudiantes universitarios de educación física, todos hombres, a quienes se les aplicó la prueba de atención de Toulouse-Piéron para registrar, mediante electroencefalograma, su actividad cerebral por 8 minutos durante la ejecución de la prueba. Para el registro de la actividad cerebral se usó el dispositivo Emotiv Epoc®. Resultados. Se observaron diferencias intra e inter-hemisfericas en la relación orden/caos entre los participantes en las regiones prefrontales, temporales y occipitales (p<0.05), así como diversas correlaciones entre estas regiones (r>0.600), las cuales variaron tanto entre los sujetos, como a nivel individual a medida que avanzaba la ejecución de la prueba. Conclusión. A medida que la ejecución de la prueba avanzaba, las asimetrías hemisféricas aumentaban, por lo que es posible concluir que la participación en procesos cognitivos continuos produce diferencias en la actividad cerebral; sin embargo, es necesario realizar estudios similares en muestras con diferentes características (diversos grupos etarios, mujeres, etc.) y donde se apliquen otras pruebas de atención para poder confirmar o contrastar los resultados aquí reportados.

Abstract Introduction: Considering its aperiodic dynamics, brain activity can be studied by means of non-linear functions or chaotic systems. Objective: To analyze the inter- and intra-hemispheric differences of the order/chaos relationship observed in the beta waves of university students during their participation in an attention test. Materials and methods: The sample was composed of 10 university physical education students, all males, who were administered the Toulouse-Piéron Concentrated Attention Test to record, by means of electroencephalogram, their brain activity for 8 minutes during the execution of the test. The Emotiv Epoc® device was used to record brain activity. Results: Intra- and inter-hemispheric differences were observed in the order/chaos relationship among the participants in the prefrontal, temporal and occipital regions (p<0.05), as well as various correlations between these regions (r>0.600), which varied both between participants and individually as the execution of the test progressed. Conclusion: As the test progressed, hemispheric asymmetries increased, which allows concluding that engaging in continuous cognitive processes causes brain activity differences. However, it is necessary to carry out similar studies in samples with different characteristics (different age groups, women, etc.) in which other attention tests are used to confirm or contrast the results reported here.